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This application is a continuation of application Ser. No. 08/022,754 filed Feb. 19, 1993, which is a continuation of application Ser. No. 07/893,889 filed Jun. 4, 1992, which is a continuation of application Ser. No. 07/688,274 filed Apr. 22, 1991, all now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an electronic camera of the type which has a digital memory.
2. Description of the Related Art
Due to developments in semiconductor memories occurring in recent years, electronic still cameras have been proposed which have a memory for temporarily storing a video signal representative of a single image (a single field or a single frame) obtained by an imaging device. (This signal being stored prior to recording on a disk or the like.) FIG. 1 shows such an electronic still camera.
In this electronic still camera, a light from an object passes through a plurality of optical lenses 1, 2, 3, and 4, a shutter mechanism 5, an infrared radiation cutting filter 6, an optical low-pass filter 7, and an on-chip color filter 8 and reaches the image forming surface of an imaging device 9 which converts the light into an electric signal, as shown in FIG. 1. The obtained video signal is read out to sample-hold circuits 10 separately as R (red), G (green), and B (blue) signals and sampled and held by the sample-hold circuits 10.
The outputs of the sample-hold circuits 10 are gain controlled by variable gain amplifiers 11-1 and 11-2 for controlling white balance and a variable gain amplifier 12 for adjusting the sensitivity, the outputs of the amplifiers 11-1, 12, and 11-2 being respectively supplied to A/D (analog-digital) converters 13-1, 13-2 and 13-3. The A/D converters 13-1, 13-2 and 13-3 have a clamping function and gamma correcting function. Therefore, in addition to A/D conversion, level clamping and gamma correction can also be conducted on the video signal supplied to the A/D converters.
The obtained digital video signal is converted into a switched Y (luminance) signal by a switch 14 which is switched over on a time sharing basis, and then temporarily stored in a normally-used FIFO type memory 15.
The individual components 9 to 14 are operated synchronously with a clock supplied from a clock generating circuit 16 controlled by a system controller 17. The clock generating circuit 16 suspends the supply of the clock signals to the individual components 9 to 14 when the video signal representing a single image has been stored in the memory 15, and thereby reduces power consumption.
The system controller 17 generates a white balance control signal and an iris control signal on the basis of the outputs of an automatic white balance (AWB) sensor 18 and of an automatic iris (AE) sensor 19. The system controller 17 also generates various types of control signals in accordance with the operation of an operation panel 20.
After the video signal representative of a single image has been stored in the memory 15, the stored video signal is read out from the memory 15. The read-out video signal is first supplied to a vertical aperture correcting circuit in sequence.
The vertical aperture correcting circuit includes two series-connected 1H line memories 21-1 and 21-2, and a normally used vertical finite impulse response (FIR) filter 22 composed of coefficient units and an adder. The vertical aperture correcting circuit conducts vertical aperture correction on the video signal supplied thereto. The video signal output from the vertical aperture correcting circuit is converted into an analog signal by a digital-analog (D/A) converter 23. The obtained analog signal passes through a low-pass filter 24 which removes the clock component of the signal, and then a clamping circuit (CL) 25 which clamps the signal to a predetermined level. The video signal further passes through a blanking circuit (BL) 26, then a sink adder 27 which adds a synchronizing signal to the video signal, and is then supplied to a recording/reproducing apparatus 28 which records the video signal on a recording medium, such as a magnetic disk.
The output (the switched Y signal) of the 1H line memory 21-1 of the vertical aperture correcting circuit is separated into color signals of R, G and B by a switch 30. The individual color signals pass through a plurality of horizontal FIR filters 31-1, 31-2 and 31-3, each including a plurality of delay circuits (latch circuits), a plurality of coefficient units and an adder, which limits the band thereof. The resultant color signals are converted into color difference signals by encoders 32 and 33. The obtained color difference signals are supplied to a switch 34 and converted into a line sequential color difference signal.
The resultant line sequential color difference signal is converted into an analog signal by a D/A converter 35. The obtained analog signal passes through a low-pass filter 36, a clamping circuit 37 and a blanking circuit 38 and is then supplied to the recording/reproducing apparatus 28.
The above-described individual components are driven synchronously with a clock supplied from the clock generating circuit 16.
In the thus-arranged electronic still camera, since the 1H line memories 21-1 and 21-2 are required for vertical aperture correction in addition to the memory 15, the scale of the circuit is increased, thus increasing production cost.
Furthermore, the aforementioned digital filters (horizontal FIR filters 31 and vertical FIR filter 22) are large in size and consume a large amount of power. These drawbacks make integration of the digital filters difficult.
SUMMARY OF THE INVENTION
In view of the aforementioned drawbacks associated with a conventional electronic still camera, an object of the present invention is to provide an electronic still camera which enables the circuit scale to be reduced.
The present invention in one aspect provides an electronic camera which comprises a memory means for storing a video signal representing at least a single image, a signal processing means for conducting digital processing in a vertical direction with a predetermined characteristic on the video signal read out from the memory means in the vertical direction and for conducting digital processing in a horizontal direction with another predetermined characteristic which is different from said predetermined characteristic on the video signal read out from the memory means in the horizontal direction, and a control means for switching over reading out of the video signal from the memory means, between in the vertical direction and the horizontal direction and for switching over the processing characteristic of the signal processing means between the predetermined characteristic and another predetermined characteristic which is different from the first predetermined characteristic.
The present invention in another aspect pertains to an electronic still camera comprising a memory means for storing a video signal representative of at least a single image, the memory means allowing for write-in and read-out operations of the video signal in both horizontal and vertical directions, a signal processing means for conducting a predetermined signal processing on the video signal output from the memory means, and a control means for changing the signal processing conducted by the signal processing means depending on whether the signal is read out from the memory means in the horizontal or vertical directions.
The present invention in yet another aspect pertains to an electronic still camera comprising an imaging means for producing a video signal by conducting photoelectric conversion on a light from an object, a memory means for storing the video signal obtained by the imaging means, and a signal processing means for conducting a predetermined signal processing on the signal read out from the memory means, the signal processing means changing its processing operations depending on how the signal is read out from said memory means.
The present invention in still a further aspect pertains to a signal processing circuit comprising a signal storage means, a control means for reading out a signal from the signal storage means in a predetermined read-out order, and a signal processing means for conducting a signal processing corresponding to the read-out order on the signal read out from the signal storage means.
Other objects and advantages of the invention will become apparent during the following discussion of the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a conventional electronic still camera;
FIG. 2 is a block diagram of a first embodiment of an electronic still camera according to the present invention;
FIG. 3 is a block diagram of a second embodiment of the electronic still camera according to the present invention; and
FIG. 4 is a circuit diagram of a memory used in the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Preferred embodiments of an electronic still camera according to the present invention will now be described with reference to FIGS. 2 to 4. In the discussion of the following embodiments, the same reference characters are used to denote components which are the same as those in the conventional camera, description thereof being omitted.
In a first embodiment, a memory 40, such as a RAM, is used as the memory for temporarily storing a video signal representative of a single image. Consequently, the video signal can be written in both the horizontal and vertical scanning directions, and the sequentially written video signal can be read out in both horizontal and vertical scanning directions. That is, in the present invention, a video signal can be sequentially written in a horizontal scanning direction in the horizontal write mode, and the video signal can be read out in the horizontal scanning direction in the horizontal read-out mode by designating an address by means of an address designating circuit in the memory which is controlled by the system controller 17. Also, the video signal can be sequentially written in the vertical scanning direction in the vertical write mode, and the video signal can be sequentially read out in the vertical scanning direction in the vertical read-out mode.
The coefficients of coefficient units h1 to h5 which constitute a V.H. single FIR filter 41 can be varied between values respectively corresponding to the vertical and horizontal filters.
The input and output of the FIR filter 41 are respectively switched over by H/V switches 42 and 43 synchronously with the switch-over between the vertical and horizontal modes.
The above-described individual operation modes are controlled by the system controller 17, which may be in the from of a microcomputer.
In the electronic still camera having the above-described configuration, the memory 40 is in the horizontal write mode when the operation of the still camera is started, and the output from the switch 14 is thereby sequentially written in the memory in the horizontal scanning direction.
When the video signal representative of the single image has been written in the memory 40, the memory 40 is set in the vertical read-out mode, and the written video signal is thus sequentially read out in the vertical scanning direction.
The read-out video signal is supplied to the FIR filter 41 through the H/V switch 42. At that time, predetermined values are set in the FIR filter 41, as mentioned above, and the FIR filter 41 functions as the vertical aperture correcting circuit.
The video signal on which vertical aperture correction has been conducted is supplied again to the memory 40 through the H/V switch 43 and written in the memory which is in the vertical write mode.
Switch-over between the read-out mode and the write mode is conducted during the aperture correction operation each time the FIR filter 41 completes aperture correction on one pixel in the vertical direction. Hence, the cyclic operation, consisting of read-out from the memory 40, aperture correction, and write-in into the memory 40, is repetitively conducted for each pixel.
When aperture correction on the video signal has been completed, the memory 40 is set in the horizontal read-out mode, and the FIR filter 41 is switched over to the horizontal read-out mode. At the same time, the H/V switches 42 and 43 are switched over to the H side. Consequently, the video signal read-out from the memory 40 is supplied to the D/A converter 23 in the form of the switched Y signal, as in the case of the aforementioned conventional still camera. At the same time, the read-out video signal is separated into color signals of R, G and B by the switch 30 and then supplied to the FIR filters 41, 31-1, and 31-2.
As stated above, in the present embodiment, the memory 40 is constructed such that a video signal can be written in and read out in both the horizontal and vertical directions, and the coefficients of the coefficient units of the single V.H. FIR filter 41 can be varied in accordance with the operation mode. Consequently, the line memories and the vertical FIR filter, required for vertical aperture correction in the conventional still camera, can be eliminated.
As a result, the scale of the circuit can be reduced. This enables circuit integration and a decrease in production cost.
In the aforementioned embodiment, the recording/reproducing apparatus 28 of the type which incorporates a magnetic disk is used. However, a large-capacity solid memory 45, such as that shown in FIG. 3, may also be used.
That is, in the second embodiment, a large-capacity memory device 45 for recording the video signal on which vertical aperture correction has been performed is used in place of the recording/reproducing apparatus 28 of the first embodiment. Furthermore, the input and output lines of the memory 40 in the horizontal scanning mode are switched over by switches 46 and 47.
In this embodiment, the video signal (the output of the imaging device) written in the memory 40 in the horizontal write mode is read out in the vertical read-out mode, the aforementioned vertical aperture correction is conducted on the read-out signal, and the resultant video signal is written again in the memory 40 in the vertical write mode. Thereafter, the video signal is read-out in the horizontal read-out mode and supplied to a compressing circuit 48 through the switch 47. The compressed video signal is stored in the large-capacity memory device 45.
The video signal read-out from the large-capacity memory device 45 is expanded by an expansion circuit 49, and then supplied, through the switch 46, the memory 40 and switch 30, to the horizontal FIR filters 41 and 31 which limit the band of the signal.
The aforementioned embodiments use a RAM as the memory 40. However, the memory 40 may also be a FIFO type memory which allows for writing in and reading-out of data in both the horizontal and vertical directions.
That is, the FIFO type memory has a configuration shown in FIG. 4. In FIG. 4, reference numerals 50-11 to 50-nn, 51-1 to 51-n, 52-1 to 52-n, 53-1 to 53-n and 54-1 and 54-n denote basic cells which are the constituents of the memory. A pair of data output lines, a pair of data input lines, a write select and a read select are respectively connected to each basic cell for control of its operation.
Reference numerals 55 and 56 denote Johnson counters for conducting designation of an address in the horizontal direction. In a case where the number of bits in the horizontal direction is 910, the number of bits of the Johnson counter 55 or 56 is 910 bits. Reference numerals 57 and 58 denote Johnson counters for conducting designation of an address in the vertical direction. The number of bits in the vertical direction is 263 bits in a case where a television signal conforming to the NTSC standard is handled. A reference numeral 59 denotes a terminal to which a mode control signal for designating in/out in the horizontal direction and in/out in the vertical direction is supplied. Read/write operations in the horizontal and vertical directions are designated by this mode control signal.
The basic operation of the thus-arranged memory will be described below. Write-in and read-out operations in the horizontal mode are known, and a detailed description thereof has been omitted.
In the vertical mode, a clock is input to clock input terminals VCK. The V counters 57 and 58 are driven by this clock. Each time the V counters 57 and 58 complete counting for one column, the H counters 55 and 56 are incremented. That is, the V counters 57 and 58 drive the line memory in the vertical direction, and the H counters 55 and 56 drive the basic cells.
Transfer of data in the write-in and read-out modes is conducted in the following manner: first, data is transferred in sequence to the basic cells which constitute the line memory in the vertical direction. Next, the data is transferred to the adjacent basic cells in the horizontal direction by a carry carried out by the V counters 57 and 58.
In this memory, write-in and read-out in the vertical direction are conducted by transferring the data representing one column in the vertical direction in the horizontal direction each time the data representing one column in the vertical direction has been written in or read-out.
In this embodiment, a buffer line memory having a capacity equivalent to one column in the vertical direction is provided. It is therefore possible to read out data from the one vertical line memory during, for example, the aperture correction operation and at the same time to store the video signal on which aperture correction has been conducted in the buffer line memory.
As will be understood from the foregoing description, in the present invention, the memory is constructed such that data can be written in and read-out from the memory in both horizontal and vertical directions. Furthermore, the characteristics of the signal processing means can be varied in accordance with the operation mode. In consequence, the line memories and vertical FIR filter, required in the conventional electronic still camera, can be eliminated.
As a result, the scale of the circuit can be reduced. This enables circuit integration and a decrease in production cost.
Furthermore, in the present invention, the single signal processing means is time-shared for both vertical and horizontal processings. This also allows the scale of the circuit to be reduced.
While the present invention has been described with respect to what is presently considered to be the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. To the contrary, the invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions. | An electronic camera includes a memory circuit for storing a video signal representing at least a single image, a signal processing circuit for conducting digital processing in a vertical direction with a predetermined characteristic on the video signal read out from the memory circuit in the vertical direction and for conducting digital processing in a horizontal direction with another predetermined characteristic which is different from the predetermined characteristic on the video signal read out from the memory circuit in the horizontal direction, and a control circuit for switching over reading out of the video signal from the memory circuit between the vertical direction and the horizontal direction and for switching over the processing characteristic of the signal processing circuit between the predetermined characteristic and the another predetermined characteristic which is different from the predetermined characteristic. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a vaporizer for CVD, a solution-vaporization type CVD apparatus and a vaporization method for CVD, and more particularly, a vaporizer for CVD, a vaporization method for CVD and a solution-vaporization type CVD apparatus using the CVD vaporizer which suppress clogging of a solution pipe or the like and extend continuous operation times.
[0003] 2. Description of the Related Art
[0004] In CVD technologies adopted by semiconductor industries from around 1970, to form a thin film, a reactant in a gaseous state is introduced into a reactor, and a chemical reaction is caused, thereby forming a thin film with various compositions on a semiconductor substrate made of silicon or the like. The CVD technologies, however, has a limitation that a thin film cannot be formed by CVD unless a gaseous reactant is prepared.
[0005] At IEDM (International Electron Devices Meeting) of 1987, W. I. KINNEY et al. announced a technology for fabricating a high speed nonvolatile memory FeRAM (FRAM: Ferroelectric Random Access Memory) by utilizing the polarization phenomenon of a ferroelectric material (like PZT, or SBT). At that time, a thin film of a ferroelectric material like PZT, or SBT could not be formed by CVD because preparation of a gaseous chemical containing Zr, Sr, Bi was impossible. Accordingly, a solution coating method similar process to photo resist thing film formation was applied to fabrication of a FeRAM. There is a problem such that a ferroelectric material thin film (thickness: 400-300 nm) formed by the solution coating method, has a poor step coverage, and thinning of the film (thickness: 150-40 nm) causes increment of the number of pin holes, thereby decreasing an electrical isolation. For practical application of a FeRAM-LSI which has a plurality of steps and requires thinning of a ferroelectric material (thickness: 100-50 nm), a technology which fabricates a high-quality ferroelectric thin film by CVD is necessary.
[0006] In 1992, Dr. Shiozaki, an assistant professor in the engineering Dept. at Kyoto University, formed a ferroelectric thin film PZT by CVD and announced this world's first formation at an academic conference. A CVD apparatus adopted by Dr. Shiozaki employed a scheme of sublimating and gasifying a solid chemical.
[0007] The scheme of sublimating and gasifying a solid chemical, however, has following problems. That is, it is difficult to increase a flow rate of a reactant because a rate of sublimation when sublimating a solid chemical is low and, because of the difficulty of flow rate control of the reactant, a deposition rate of a thin film is low, resulting in a poor reproducibility. Further, it is difficult to carry the sublimated chemical to a reactor with a pipe heated at approximately 250° C.
[0008] In order to make an additional experiment on the technique announced by Dr. Shiozaki, the inventor of the present invention purchased the same CVD apparatus used by Dr. Shiozaki from the same manufacturer with Dr. Shiozaki's assistance, and performed a film formation experiment. Immediately after starting operation of the CVD apparatus, however, a high-temperature pipe was clogged. After fixed, the high-temperature pipe was then heated extraordinary. Based on such an experience, the inventor concluded that a technology of evenly heating thin, long stainless pipes (external diameter: ¼ inch and length: 1 m of several pipes) with a plurality of valves disposed on the middle portions thereof at 250±5° C. is extremely difficult.
[0009] Based on the above-described experience, the inventor concluded that it is difficult to put the sublimation type CVD apparatus to practical use. Consequently, the inventor succeeded the world's first deposition of a high-quality thin film of a ferroelectric material SBT by employing a solution-vaporization CVD method (so-called flash CVD method). He announced this success at an international academic conference, ISIF '96 (“Performance of SrBi 2 Ta 2 O 9 Thin Films Grown by Chemical Vapor Deposition for Nonvolatile Memory Applications”. C. Isobe, H. Yamoto, H. Yagi et al. 9 th International Symposium on Integrated Ferroelectrics. March, 1996 ), and first verified the possibility of commercialization of a ferroelectric memory FeRAM around the world.
[0010] As a vaporizer for producing a reaction gas for SBT thin film synthesis formation by dissolving solid material in solvent so as to produce solution and gasifying the solution at a high temperature, one made by ATMI Inc. was initially adopted. This vaporizer, however, could not be adopted by a CVD apparatus for mass production because it was clogged in a matter of ten hours. Accordingly, in 1996, the inventor placed an order with Mr. Yoshioka of Shimadzu Corporation and Dr. Toda, a professor of Material Engineering dept. of Faculty of Engineering at Yamagata University to develop and manufacture a high-performance solution supply control system and a high performance vaporizer necessary for stably forming a high-quality SBT thin film. A developed and delivered apparatus (solution supply control system and vaporizer), however, had the following problem, and it was difficult to stably form a SBT thin film. Meanwhile, this apparatus (solution supply control system and vaporizer) is disclosed in Patent Literature 1 (Japanese Unexamined Patent Publication No. 2000-216150) and Patent Literature 2 (Japanese Unexamined Patent Publication No. 2002-105646).
[0011] As a reactant for synthesizing a SBT thin film, Sr(DPM) 2 , BiPh 3 , Ta(OEt) 5 , Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 , Bi(OtAm) 3 , Bi(MMP) 3 , and the like. are used, and particularly, using Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 +Bi(MMP) 3 makes it possible to perform high-speed deposition (5-100 nm/min) at 320-420° C., thereby enabling formation of a high-quality SBT thin film having good step coverage and electrical property. The above apparatus (solution supply control system and vaporizer), however, was clogged immediately when Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 +Bi(MMP) 3 was used as a reactant chemical. When the inventor researched and examined the reason of clogging, he found the reason why is that when solution of Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 +Bi(MMP) 3 was mixed at a room temperature, Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 and Bi(MMP) 3 reacted with each other and a material which had a small solubility and was unlikely to sublimate was synthesized, thereby clogging a path for allowing the solutions to flow and the leading end of a vaporization tube. This phenomenon will now be explained in detail.
[0012] FIG. 4 is a TG CHART (Ar 760/10 Torr, O 2 760 Toor) of Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 . This figure illustrates: a graph 101 representing changes in the weight of a sample of Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 when the sample is undergone temperature rise from 30 to 600° C. at a rate of 10° C./min. under argon atmosphere at a pressure of 760 Torr and a flow rate of 100 ml/min., a graph 102 representing changes in the weight of the sample when it is undergone temperature rise from 30 to 600° C. at a rate of 10° C./min. under argon atmosphere at a pressure of 10 Torr and a flow rate of 50 ml/min., and a graph 103 representing changes in the weight of the sample when it is undergone temperature rise from 30 to 600° C. at a rate of 10° C./min. under oxygen atmosphere at a pressure of 760 Torr and a flow rate of 100 ml/min. It can be seen from the figure that Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 completely sublimes at approximately 220° C. under argon atmosphere at a pressure of 10 Torr.
[0013] FIG. 5 is a TG CHART (Ar 760/10 Torr, O 2 760 Toor) of Bi(OtAm) 3 . This figure illustrates a graph 111 representing changes in the weight of a sample of Bi(OtAm) 3 when the sample is undergone temperature rise from 30 to 600° C. at a rate of 10° C./min. under argon atmosphere at a pressure of 760 Torr and a flow rate of 100 ml/min., a graph 112 representing changes in the weight of the sample when it is undergone temperature rise from 30 to 600° C. at a rate of 10° C./min. under argon atmosphere at a pressure of 10 Torr and a flow rate of 50 ml/min., and a graph 113 representing changes in the weight of the sample when it is undergone temperature rise from 30 to 600° C. at a rate of 10° C./min. under oxygen atmosphere at a pressure of 760 Torr and a flow rate of 100 ml/min. It can be seen from the figure that approximately 98% of Bi(OtAm) 3 sublimes at approximately 130° C. under argon atmosphere at a pressure of 10 Torr.
[0014] FIG. 6 is a TG CHART (Ar 760/10 Torr, O 2 760 Toor) of Bi(MMP) 3 . This figure illustrates a graph 121 representing changes in the weight of a sample of Bi(MMP) 3 when the sample is undergone temperature rise from 30 to 600° C. at a rate of 10° C./min. under argon atmosphere at a pressure of 760 Torr and a flow rate of 100 ml/min., a graph 122 representing changes in the weight of the sample when it is undergone temperature rise from 30 to 600° C. at a rate of 10° C./min. under argon atmosphere at a pressure of 10 Torr and a flow rate of 50 ml/min., and a graph 123 representing changes in the weight of the sample when it is undergone temperature rise from 30 to 600° C. at a rate of 10° C./min. under oxygen atmosphere at a pressure of 760 Torr and a flow rate of 100 ml/min. It can be seen from the figure that Bi(MMP) 3 completely sublimes at approximately 150° C. under argon atmosphere at a pressure of 10 Torr.
[0015] FIG. 7 is a TG CHART (Ar 760/10 Torr, O 2 760 Toor) of a mixture of Bi(OtAm) 3 /Sr[Ta(OEt) 6 ] 2 . This figure illustrates a graph 131 representing changes in the weight of a sample of Bi(OtAm) 3 /Sr[Ta(OEt) 6 ] 2 when the sample is undergone temperature rise from 30 to 600° C. at a rate of 10° C./min. under argon atmosphere at a pressure of 760 Torr and a flow rate of 100 ml/min., and a graph 133 representing changes in the weight of the sample when it is undergone temperature-rise from 30 to 600° C. at a rate of 10° C./min. under oxygen atmosphere at a pressure of 760 Torr and a flow rate of 100 ml/min. It can be seen from the figure that only 80% of the mixture of Bi(OtAm) 3 /Sr[Ta(OEt) 6 ] 2 sublimes under argon atmosphere even if it is heated at greater than or equal to 300° C.
[0016] As explained, both Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 and Bi(OtAm) 3 almost completely sublime in individuals, but when they mixed with each other, a part of them do not sublime. The deterioration of a sublimation characteristic may cause clogging of the vaporizer.
[0017] A reason for the deterioration of the sublimation characteristic can be seen from NMR characteristic (Nuclear Magnetic Resonance of H) as illustrated in FIG. 8 . When Bi(OtAm) 3 and Sr[Ta(OEt) 6 ] 2 are mixed, a new NMR characteristic is observed, and this represents that a new chemical compound is formed and is in presence.
[0018] FIG. 9 is a TG CHART (Ar 760 Torr) of a mixture of Bi(MMP) 3 /Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 . This figure illustrates a graph representing changes in the weight of a sample of Bi(MMP) 3 /Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 when the sample is undergone temperature rise from 30 to 600° C. at a rate of 10° C./min. under argon atmosphere at a pressure of 760 Torr and a flow rate of 100 ml/min. It can be seen from the figure that only 80% of the mixture of Bi(MMP) 3 /Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 sublimes under argon atmosphere.
[0019] FIG. 10 is a TG CHART (Ar 760/10 Torr, O 2 760 Toor) of BiPh 3 . This figure illustrates a graph 141 representing changes in the weight of a sample of BiPh 3 when the sample is undergone temperature rise from 30 to 600° C. at a rate of 10° C./min. under argon atmosphere at a pressure of 760 Torr and a flow rate of 100 ml/min., a graph 142 representing changes in the weight of the sample when it is undergone temperature rise from 30 to 600° C. at a rate of 10° C./min. under argon atmosphere at a pressure of 10 Torr and a flow rate of 50 ml/min., and a graph 143 representing changes in the weight of the sample when it is undergone temperature rise from 30 to 600° C. at a rate of 10° C./min. under oxygen atmosphere at a pressure of 760 Torr and a flow rate of 100 ml/min. It can be seen from the figure that 100% of BiPh 3 sublimes at approximately 200° C.
[0020] FIG. 11 is a TG CHART (Ar 760/10 Torr, O 2 760 Toor) of BiPh 3 /Sr[Ta(OEt) 6 ] 2 mixture. This figure illustrates a graph 151 representing changes in the weight of a sample of BiPh 3 /Sr[Ta(OEt) 6 ] 2 mixture when the sample is undergone temperature rise from 30 to 600° C. at a rate of 10° C./min. under argon atmosphere at a pressure of 760 Torr and a flow rate of 100 ml/min., and a graph 153 representing changes in the weight of the sample when it is undergone temperature rise from 30 to 600° C. at a rate of 10° C./min. under oxygen atmosphere at a pressure of 760 Torr and a flow rate of 100 ml/min. It can be seen from the figure that almost 100% of BiPh 3 /Sr[Ta(OEt) 6 ] 2 mixture sublimes at approximately 280° C.
[0021] FIG. 12 illustrates NMR characteristics and mixing stabilities of BiPh 3 and Sr[Ta(OEt) 6 ] 2 . No synthesis of a new material is observed in a mixture of BiPh 3 /Sr[Ta(OEt) 6 ] 2 .
[0022] FIG. 13 is a TG-DTA CHART (O 2 760 Torr) of BiPh 3 . As illustrated in the figure, the oxidation reaction of BiPh 3 occurs at 465° C. It can be seen that because the oxidizing temperature of BiPh 3 is so high with respect to 259° C. of Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 , 209° C. of Bi(MMP) 3 , and 205° C. of Bi(OtAm) 3 , it is difficult to adopt BiPh 3 .
[0023] Bi(OtAm) 3 causes a hydrolysis reaction with only 180 ppm of moisture. This shows that Bi(OtAm) 3 is immeasurably more sensitive to moisture than Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 causing a hydrolysis reaction with 1650 ppm of moisture, and Bi(MMP) 3 causing that reaction with 170 ppm of moisture, and treatment of Bi(OtAm) 3 is difficult. Since moisture is certainly in presence, a possibility that Bi(OtAm) 3 reacts with moisture and formed Bi oxide clogs up a pipe, a flow meter, and the like may increase.
[0024] Patent Literature 1: Japanese Unexamined Patent Publication No. 2002-216150 (paragraphs 76 to 78, paragraphs 145 to 167, FIG. 3 , and FIG. 8 )
[0025] Patent Literature 2: Japanese Unexamined Patent Publication No. 2002-105646 (paragraphs 13 to 14, and FIG. 2 ) The problems of the conventional technologies described above can be summarized as follows.
[0026] The technology of gasifying a solid chemical by sublimation at a room temperature and using this gas as a reactive gas has a problem such that a deposition rate of thin film is low and varies, whereby it may be difficult to put it in practical use.
[0027] In contrast, the solution-vaporization type CVD method using a solid chemical at a room temperature, dissolving the solid chemical in a solvent, atomizing it, and then vaporizing it at high temperature, has a high deposition rate of thin film, but, there is a phenomenon that a chemical reaction occurs in a solution state, thereby clogging up a solution pipe or the like. As the solution-pipe or the like is clogged, the CVD apparatus can be continuously operated for short times. Therefore, this makes it necessary that a solution supplying system be devised.
[0028] The present invention has been made in view of the foregoing circumstances, and it is an object of the present invention to provide a vaporizer for CVD, a solution-vaporization type CVD apparatus, and a vaporization method for CVD which suppress clogging of a solution pipe or the like and extend continuous operation times.
SUMMARY OF THE INVENTION
[0029] To achieve the object, a vaporizer for CVD oc the invention comprises
[0030] a dispersion unit which disperses a plurality of raw-material solutions into a carrier gas in a fine particulate or misty form,
[0031] a plurality of raw-material-solution passages which respectively supply the plurality of raw-material solutions, separately from one another, to the dispersion unit,
[0032] a carrier gas passage which supplies the carrier gas to the dispersion unit separately from each of the plurality of raw-material solutions,
[0033] a vaporization unit which vaporizes the plurality of raw-material solutions dispersed by the dispersion unit, and
[0034] an orifice which is connected to the vaporization unit and the dispersion unit and through which the plurality of raw-material solutions dispersed by the dispersion unit are introduced into the vaporization unit.
[0035] As the vaporizer for CVD has the plurality of raw-material-solution passages, it is possible to provide the dispersion unit with the plurality of raw-material solutions separately from each other. This prevents the plurality of raw-material solutions from causing a chemical reaction in solution states, and clogging in the raw-material solution passages.
[0036] In the vaporizer for CVD, it is preferable that the dispersion unit should be disposed between the orifice and individual leading ends of the plurality of raw-material-solution passages, and the orifice should have a diameter smaller than a diameter of each of the plurality of raw-material-solution passages and a diameter of the carrier gas passage.
[0037] In the vaporizer for CVD, it is preferable that when the raw-material solutions are vaporized, the vaporization unit should become a depressurized state and the dispersion unit should become a pressurized state.
[0038] A vaporizer for CVD of the invention comprises
[0039] a plurality of raw-material-solution pipes which respectively supply a plurality of raw-material solutions separately from one another,
[0040] a carrier gas pipe which is disposed in such a manner as to surround exteriors of the plurality of raw-material-solution pipes and allows a pressurized carrier gas to flow to the exterior of each of the plurality of raw-material-solution pipes,
[0041] an orifice provided in a leading end of the carrier gas pipe and spaced away from leading ends of the plurality of raw-material-solution pipes,
[0042] a vaporization tube connected to the leading end of the carrier gas pipe and led to an interior of the carrier gas pipe via the orifice, and
[0043] heating means for heating the vaporization tube.
[0044] As the vaporizer for CVD has the plurality of raw-material-solution passages, it is possible to provide the dispersion unit with the plurality of raw-material solutions separately from each other. This prevents the plurality of raw-material solutions from causing a chemical reaction in solution states, and clogging in the raw-material solution passages. It is structured in such a way that the exteriors of the plurality of raw-material-solution pipes are wrapped by the carrier gas pipe and a carrier gas is allowed to flow to a space between the raw-material-solution pipes and the carrier gas is employed, and a vaporization tube for adiabatic expansion is provided on the downstream side of a flow. That is, as the pressurized carrier gas is allowed to flow to the space outward the raw-material-solution pipes, it is possible to suppress temperature rise at the raw-material-solution pipes and the carrier gas pipe. Therefore, because it is possible to suppress that only the solvent in the raw-material solution is vaporized between the orifice and the leading end of the raw-material-solution pipe, occurrence of a chemical reaction of the raw-material solutions is suppressed, and clogging at the orifice and the neighborhood thereof is suppressed.
[0045] In the vaporizer for CVD, the carrier gas and the plurality of raw-material solutions are mixed between the orifice in the carrier gas pipe and the leading ends of the plurality of raw-material-solution pipes, the plurality of raw-materials are dispersed into the carrier gas in a fine particulate or misty form, the dispersed fine particulate or misty raw-material solutions are introduced into the vaporization tube through the orifice and heated to vaporize by the heating means. Accordingly, it is suppressed that only a solvent in the raw-material solution vaporizes at the orifice or the vaporization tube near the orifice, this suppresses occurrence of a chemical reaction of the raw-material solutions, and clogging.
[0046] In the vaporizer for CVD, it is preferable that the orifice should have a diameter smaller than a diameter of each of the plurality of raw-material-solution pipes and a diameter of the carrier gas pipe.
[0047] In the vaporizer for CVD, it is possible that the plurality of raw-material solutions be a mixture of Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 and a solvent and a mixture of Bi(MMP) 3 and a solvent, and the carrier gas be an argon gas or a nitrogen gas.
[0048] A solution-vaporization type CVD apparatus of the invention comprises any one of the vaporizers for CVD.
[0049] A solution-vaporization type CVD apparatus of the invention comprises
[0050] any one of the vaporizers for CVD, and
[0051] a reaction chamber connected to the vaporization tube,
[0052] wherein deposition is carried out with the plurality of raw-material solutions vaporized in the vaporization tube.
[0053] A vaporization method for CVD of the invention comprises supplying a plurality of raw-material solutions and a carrier gas to a dispersion unit separately from one another, mixing the plurality of raw-material solutions and the carrier gas in the dispersion unit and dispersing the plurality of raw-material solutions into the carrier gas in a fine particulate or misty form, and vaporizing the raw-material solutions by adiabatic expansion immediately after dispersion.
[0054] In the vaporization method for CVD, it is preferable that the raw-material solutions should be dispersed in a fine particulate or misty form within one second after mixture of the raw-material solutions. This makes it possible to suppress that only a solvent in the raw-material solution vaporizes in the vaporization unit, and it is thus suppressed that the raw-material solutions cause a chemical reaction in the dispersion unit, thereby suppressing clogging of the dispersion unit and the orifice.
[0055] As explained, the invention provides a vaporizer for CVD, a solution-vaporization type CVD apparatus, and a vaporization method for CVD which suppress clogging of a solution pipe or the like and extend continuous operation times.
BRIEF DESCRIPTION OF THE DRAWINGS
[0056] FIG. 1A is a structural diagram exemplarily illustrating the solution supply system of a vaporizer for CVD according to the first embodiment of the present invention, FIG. 1B is a cross-sectional view exemplarily illustrating the solution supply system, a dispersion unit, and a vaporization unit, FIG. 1C is a structural diagram exemplarily illustrating the solution supply system of a vaporizer for CVD according to a second embodiment, and FIG. 1D is a structural diagram exemplarily illustrating the solution supply system of a vaporizer for CVD according to a third embodiment;
[0057] FIG. 2 is a diagram illustrating an experimental result of formation of an SBT thin film by continuously operating a solution-vaporization type CVD apparatus having a vaporizer for CVD of the first embodiment;
[0058] FIG. 3 is a diagram illustrating the result of an experiment which formed an SBT thin film by continuous operation of the solution-vaporization type CVD apparatus and measured the compositions of Bi, Ta, and Sr in the SBT thin film;
[0059] FIG. 4 is a TG CHART (Ar 760/10 Torr, O 2 760 Toor) of Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 ;
[0060] FIG. 5 is a TG CHART (Ar 760/10 Torr, O 2 760 Toor) of Bi(OtAm) 3 ;
[0061] FIG. 6 is a TG CHART (Ar 760/10 Torr, O 2 760 Toor) of Bi(MMP) 3 ;
[0062] FIG. 7 is a TG CHART (Ar 760/10 Torr, O 2 760 Toor) of the mixture of Bi(OtAm) 3 /Sr[Ta(OEt) 6 ] 2 ;
[0063] FIG. 8 a diagram illustrating NMR characteristic (nuclear magnetic resonance of H);
[0064] FIG. 9 is a TG CHART (Ar 760/10 Torr, O 2 760 Toor) of the mixture of Bi(MMP) 3 /Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 ;
[0065] FIG. 10 is a TG CHART (Ar 760/10 Torr, O 2 760 Toor) of BiPh 3 ;
[0066] FIG. 11 is a TG CHART (Ar 760/10 Torr, O 2 760 Toor) of BiPh 3 /Sr [Ta(OEt) 6 ] 2 ;
[0067] FIG. 12 is a diagram illustrating NMR characteristics representing mixing stabilities of BiPh 3 and Sr[Ta(OEt) 6 ] 2 ; and
[0068] FIG. 13 is a TG-DTA CHART (O 2 760 Torr) of BiPh 3 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0069] Preferred embodiments of the present invention will be explained with reference to the accompanying drawings.
First Embodiment
[0070] FIG. 1A is a structural diagram exemplarily illustrating the solution supply system of a vaporizer for CVD according to the first embodiment of the present invention, and FIG. 1B is a cross-sectional view exemplarily illustrating the solution supply system, a dispersion unit, and a vaporization unit.
[0071] As illustrated in FIGS. 1A and 1B , the vaporizer for CVD has first and second raw-material-solution pipes 1 , 2 . The first raw-material-solution pipe 1 is disposed adjacent to the second raw-material-solution pipe 2 in parallel therewith. A carrier gas pipe 3 is disposed outward the first and second raw-material-solution pipes 1 , 2 . The carrier gas pipe 3 is so formed as to have an internal diameter larger than the sum of the external diameter of the first pipe 1 and that of the second raw-material-solution pipe 2 . That is, the first and second raw-material-solution pipes 1 , 2 are inserted into the carrier gas pipe 3 , and the pipe 3 is formed in such a manner as to wrap the first and second raw-material-solution pipes 1 , 2 .
[0072] The base end side of the first raw-material-solution pipe 1 is connected to a first supply mechanism 4 which supplies a chemical 1 and a solvent. The first supply mechanism 4 has a supply source which supplies the chemical 1 (for example, Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 ), and a supply source which supplies the solvent. A valve 6 and a mass-flow controller (not illustrated) are provided between the supply source of the chemical 1 and the first raw-material-solution pipe 1 . A valve 7 and a mass-flow controller (not illustrated) are provided between the supply source of the solvent and the first raw-material-solution pipe 1 . The solvent and the chemical 1 flow into each other (mix) between the supply source of the solvent and the first raw-material-solution pipe 1 .
[0073] The base end side of the second raw-material-solution pipe 2 is connected to a second supply mechanism 5 which supplies a chemical 2 and a solvent. The second supply mechanism 5 has a supply source which supplies the chemical 2 (for example, Bi(MMP) 3 ), and a supply source which supplies the solvent. A valve 8 and a mass-flow controller (not illustrated) are provided between the supply source of the chemical 2 and the second raw-material-solution pipe 2 . A valve 9 and a mass-flow controller (not illustrated) are provided between the supply source of the solvent and the second raw-material-solution pipe 2 . The solvent and the chemical 2 flow into each other (mix) between the supply source of the solvent and the second raw-material-solution pipe 2 .
[0074] The base end side of the carrier gas pipe 3 is connected to a third supply mechanism 12 which supplies an argon gas and a nitrogen gas. The third supply mechanism 12 has a supply source which supplies the argon gas (Ar), and a supply source which supplies the nitrogen-gas (N 2 ). A valve 10 and a mass-flow controller (not illustrated) are provided between the supply source of the argon gas and the carrier gas pipe 3 . A valve 11 and a mass-flow controller (not illustrated) are provided between the supply source of the nitrogen gas and the carrier gas pipe 3 .
[0075] The leading end of the carrier gas pipe 3 is connected to one end of a vaporization tube 13 . The carrier gas pipe 3 has an orifice formed in the leading end thereof, and the orifice connects the interior of the carrier gas pipe 3 and the interior of the vaporization tube 13 . A heater provided around the vaporization tube 13 heats the vaporization tube 13 at, for example, 270° C. The other end of the vaporization tube 13 is connected to a non-illustrated reaction chamber.
[0076] Each of the leading ends of the first and second raw-material-solution pipes 1 , 2 is spaced away from the orifice. That is, a dispersion unit 14 is provided between the individual leading ends of the first and second raw-material-solution pipes 1 , 2 in the carrier gas pipe 3 and the orifice. The dispersion unit 14 mixes a first raw-material solution (one made by mixing the chemical 1 and the solvent thereof) which flows out of the leading end of the first raw-material-solution pipe 1 a second raw-material solution (one made by mixing the chemical 2 and the solvent thereof) which flows out of the leading end of the second raw-material-solution pipe 2 and the argon or nitrogen gas which flows out of the carrier gas pipe 3 , and disperses the first and second raw-material solutions into the argon or nitrogen gas in a fine particulate or misty form.
[0077] Next, The operation of the aforementioned vaporizer for CVD will be explained.
[0078] First, the valve 6 is opened to supply the first raw-material solution from the first supply mechanism 4 to the first raw-material-solution pipe 1 by predetermined flow rate and pressure. The first raw-material solution is, for example, one made by mixing Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 and the solvent thereof. The valve 8 is opened to supply the second raw-material solution from the second supply mechanism 5 to the second raw-material-solution pipe 2 by predetermined flow rate and pressure. The second raw-material solution is, for example, one made by mixing Bi(MMP) 3 and the solvent thereof. The valves 10 , 11 are opened to supply the carrier gas from the third supply mechanism 12 to the carrier gas pipe 3 by predetermined flow rate and pressure. The carrier gas is, for example, the argon or nitrogen gas. A helium gas may be used.
[0079] Next, the first raw-material solution is supplied to the dispersion unit 14 through the first raw-material-solution pipe 1 , the second raw-material solution is supplied to the dispersion unit 14 through the second raw-material-solution pipe 2 , and the pressurized carrier gas is supplied to the dispersion unit 14 through the carrier gas pipe 3 . The dispersion unit 14 mixes the first raw-material solution, the second raw-material solution and the carrier gas, and the first and second raw-material solutions are dispersed into the carrier gas in a fine particulate or misty form. It is preferable that the first and second raw-material solutions should be dispersed in a fine particulate or misty form within one second after mixed by the dispersion unit 14 .
[0080] Next, the first and second raw-material solutions dispersed into the carrier gas by the dispersion unit 14 are introduced into the vaporization tube 13 through the orifice. In the vaporization tube 13 , the first and second raw-material solutions dispersed in misty forms are instantaneously heated at approximately 270° C. by the heater.
[0081] There is a large difference between a pressure in the dispersion unit 14 and a pressure in the vaporization tube 13 . The interior of the vaporizing portion 13 is in a reduced pressure state, while the interior of the dispersion unit 14 is in pressurized state. The pressure in the vaporizing portion 13 is, for example, 5 to 30 Torr, while the pressure in the dispersion unit 14 is, for example, 1500-2200 Torr. Setting such a pressure difference permits the carrier gas to jet toward the vaporization tube 13 at an ultrahigh speed, and expand (for example, adiabatic expansion) in accordance with the pressure difference. Accordingly, the sublimation temperature of chemicals contained in the first and second raw-material solutions is reduced, and thus the raw-material solutions (including the chemicals) can be vaporized by heat from the heater. Because the first and second raw-material solutions are turned to be fine mist by high speed flow of the carrier gas right after dispersed by the dispersion unit 14 , they become likely to vaporize instantaneously in the vaporization tube 13 .
[0082] The vaporizer for CVD vaporizes the first and second raw-material solutions, thereby forming a source gas in this manner. The source gas is fed to the reaction chamber through the vaporization tube 13 , and a thin film is formed by a CVD method.
[0083] According to the foregoing first embodiment, the first and second raw-material-solution pipes 1 , 2 are disposed in such a manner as to be adjacent to each other and in parallel with each other, and the carrier gas pipe 3 is disposed outward the first and second raw-material-solution pipes 1 , 2 , so that the first raw-material solution (Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 ) and the second raw-material solution (Bi(MMP) 3 ) can be supplied separately form each other to the dispersion unit 14 . This makes it possible to prevent the first and second raw-material solutions from causing a chemical reaction in solution states, thereby preventing clogging in the pipes. This extends the continuous operation time of the vaporizer for CVD.
[0084] In the embodiment, the respective exteriors of the first and second raw-material-solution pipes 1 , 2 are wrapped by the carrier gas pipe 3 having a further large diameter, a structure that the carrier gas is allowed to flow to a space in between the first and second raw-material-solution pipes 1 , 2 and the carrier gas pipe 3 is employed, and the high temperature vaporization tube is provided on the downstream side of the flow. Since the pressurized carrier gas is allowed to flow to the space outward the raw-material-solution pipes 1 , 2 at a high speed (for example, the carrier gas is 200 ml/min. to 2 L/min at 4 press.), temperature rise in the first and second raw-material-solution pipes 1 , 2 , the carrier gas pipe 3 , and the dispersion unit 14 can be suppressed. Accordingly, in the raw-material-solution pipes 1 , 2 and the dispersion unit 14 , evaporation and vaporization of the solvent only in the raw-material solution can be suppressed, the raw-material solutions are concentrated in the raw-material-solution pipes 1 , 2 and the dispersion unit 14 , rising of a viscosity and a phenomenon that deposition occurs beyond the solubility are suppressed, thereby suppressing clogging of the raw-material-solution pipes 1 , 2 , the dispersion portion 14 and the orifice
[0085] According to the embodiment, as the first and second raw-material solutions are dispersed in a fine particulate or misty form immediately after (within one second) mixed with the carrier gas by the dispersion unit 14 , it is possible to suppress that the raw-material solutions cause a chemical reaction in the dispersion unit 14 , thus suppressing clogging of the dispersion unit 14 or the orifice. Therefore, the continuous operation time of the vaporizer for CVD can be extended.
[0086] Moreover, according to the embodiment, the first and second raw-material solutions are dispersed by the dispersion unit 14 , and the dispersed raw-material solutions in the fine particulate or misty forms are heated in the vaporization tube 13 and can be vaporized (gasified) instantaneously. Therefore, because vaporization of the solvent only in the raw-material solution is suppressed at the orifice and the vaporization tube 13 near the orifice, it is possible to suppress that the raw-material solutions cause a chemical reaction at the orifice and the vaporization tube near the orifice, thereby suppressing clogging of the orifice or the vaporization tube 13 near the orifice. Therefore, the continuous operation time of the vaporizer for CVD can be extended.
[0087] As described above, according to the embodiment, by suppressing clogging of the pipes 1 to 3 , the dispersion unit 14 , the orifice and the vaporization tube 13 , the vaporizer for CVD can be operated stably and continuously for a long time. Therefore, a thin film of a ferroelectric material, such as PZT, or SBT can be formed with a good reproducibility and a controllability, and this realizes high performance vaporizer for CVD and solution-vaporization type CVD apparatus.
Second Embodiment
[0088] FIG. 1C is a structural diagram exemplarily illustrating the solution supply system of a vaporizer for CVD according to the second embodiment of the present invention, and the same structure portions as those illustrated in FIG. 1A will be denoted by the same reference numbers, and an explanation will be given of different portions only.
[0089] The vaporizer for CVD illustrated in FIG. 1C has three pipes 1 , 2 and 15 for supplying three raw-material solutions. The first raw-material-solution pipe 1 , the second raw-material-solution pipe 2 and the third raw-material-solution pipe 15 are so provided as to be adjacent to one another and in parallel with one another. The carrier gas pipe 3 is disposed outward the first to third raw-material-solution pipes 1 , 2 and 15 . That is, the first to third raw-material-solution pipes 1 , 2 and 15 are inserted into the pipe 3 , and the carrier gas pipe 3 is formed in such a manner as to wrap the first to third raw-material-solution pipes 1 , 2 and 15 .
[0090] The base end side of the third raw-material-solution pipe 15 is connected to a third supply mechanism (not illustrated) which supplies a chemical 3 and a solvent. The third supply mechanism has a supply source which supplies the chemical 3 , and a supply source which supplies the solvent. A valve (not illustrated) and a mass-flow controller (not illustrated) are provided between the supply source of the chemical 3 and the third raw-material-solution pipe 15 . A valve (not illustrated) and a mass-flow controller (not illustrated) are provided between the supply source of the solvent and the third raw-material-solution pipe 15 . The solvent and the chemical 3 flow into each other (mix) between the supply source of the solvent and the third raw-material-solution pipe 15 .
[0091] Each of the leading ends of the first to third raw-material-solution pipes 1 , 2 and 15 are spaced away from the orifice. That is, a dispersion unit is formed between the respective leading ends of the first to third raw-material-solution pipes 1 , 2 and 15 in the carrier gas pipe 3 and the orifice. The dispersion unit mixes the first raw-material solution (one made by mixing the chemical 1 and the solvent thereof) flows out of the leading end of the first raw-material-solution pipe 1 , the second raw-material solution (one made by mixing the chemical 2 and the solvent thereof) flows out of the leading end of the second raw-material-solution pipe 2 , a third raw-material solution (one made by mixing the chemical 3 and the solvent thereof) flows out of the leading end of the third raw-material-solution pipe 15 , and the argon or nitrogen gas flows out of the carrier gas pipe 3 , thereby dispersing the first to third raw-material solutions into the argon or nitrogen gas in a fine particulate or misty form.
[0092] The second embodiment can obtain the same effectiveness as that of the first embodiment.
Third Embodiment
[0093] FIG. 1D is a structural diagram exemplarily illustrating the solution supply system of a vaporizer for CVD according to a third embodiment of the present invention, and the same structure portions as those illustrated in FIG. 1C will be denoted by the same reference numbers, and an explanation will be given of only different portions.
[0094] The vaporizer for CVD illustrated in FIG. 1D has four raw-material-solution pipes 1 , 2 , 15 and 16 which supply four raw-material solutions to the dispersion unit. The first raw-material-solution pipe 1 , the second raw-material-solution pipe 2 , the third raw-material-solution pipe 15 and the fourth raw-material-solution pipe 16 are disposed in such a manner as to be adjacent to one another and in parallel with one another. The carrier gas pipe 3 is disposed outward the first to fourth raw-material-solution pipes 1 , 2 , 15 and 16 . That is, the first to fourth raw-material-solution pipes 1 , 2 , 15 and 16 are inserted into the carrier gas pipe 3 , and the carrier gas pipe 3 is formed in such a manner as to wrap the first to fourth raw-material-solution pipes 1 , 2 , 15 and 16 .
[0095] The base end of the fourth raw-material-solution pipe 16 is connected to a fourth supply mechanism (not illustrated) which supplies a chemical 4 and a solvent. The fourth supply mechanism has a supply source which supplies the chemical 4 , and a supply source which supplies the solvent. A valve (not illustrated) and a mass-flow controller (not illustrated) are provided between the supply source of the chemical 4 and the fourth raw-material-solution pipe 16 . A valve (not illustrated) and a mass-flow controller (not illustrated) are provided between the supply source of the solvent and the fourth raw-material-solution pipe 16 . The solvent and the chemical 4 flow into each other (mix) between the supply source of the solvent and the fourth raw-material-solution pipe 16 .
[0096] Each of the leading ends of the first to fourth raw-material-solution pipes 1 , 2 , 15 and 16 are spaced away from the orifice. That is, a dispersion unit is formed between the respective leading ends of the first to fourth pipes 1 , 2 , 15 and 16 in the carrier gas pipe 3 and the orifice. The dispersion unit mixes the first raw-material solution (one made by mixing the chemical 1 and the solvent thereof) flows out of the leading end of the first raw-material-solution pipe 1 , the second raw-material solution (one made by mixing the chemical 2 and the solvent thereof) flows out of the leading end of the second raw-material-solution pipe 2 , the third raw-material solution (one made by mixing the chemical 3 and the solvent thereof) flows out of the leading end of the third raw-material-solution pipe 15 , a fourth raw-material solution (one made by mixing the chemical 4 and the solvent thereof) flows out of the leading end of the fourth raw-material-solution pipe 16 , and the argon or nitrogen gas flows out of the carrier gas pipe 3 , thereby dispersing the first to fourth raw-material solutions into the argon or nitrogen gas in a fine particulate or misty form.
[0097] The third embodiment can obtain the same effectiveness as that of the second embodiment.
[0098] The present invention is not limited to the aforementioned embodiments, and can be modified in various form without departing from the broad spirit and scope of the invention. For example, the range of application of the vaporizer for CVD, the vaporization method for CVD and the solution-vaporization type CVD apparatus of the invention is wide, is not limited toe formation of a high-quality ferroelectric thin film (for instance, SBT, PZT thin film) for a FeRAM-LSI which is a high speed nonvolatile memory, and a thin film of, for example, YBCO (Super Conductive Oxide), PZT/PLZT/SBT (Filter, MEMS, Optical Interconnect, HD), Metal (Ir, Pt, Cu), Barrier Metal (TiN, TaN), High k (HfOx, Al 2 O 3 , BST or the like) can be formed with CVD.
[0099] In the foregoing embodiments, the first raw-material solution which is made by dissolving Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 in the solution thereof and the second raw-material solution which is made by dissolving Bi(MMP) 3 in the solution thereof are used, but not limited to this case, and a raw-material solution which is made by dissolving the other kind of a solid material in a solution thereof may be used. A liquid material of Sr[Ta(OEt) 5 (OC 2 H 4 OMe)] 2 or the like itself may be used as a raw-material solution, and one made by mixing a liquid material with a solution may be used.
EXAMPLES
[0100] Examples will now be explained
[0101] FIG. 2 is a diagram illustrating the result of an experiment that a solution-vaporization type CVD apparatus having the vaporizer for CVD of the first embodiment was continuously operated to form SBT thin films having a thickness of 50.9 nm on twenty silicon wafers under the same condition. According to this figure, when the SBT thin films were formed on the twenty silicon wafers by a continuous operation, it was confirmed that the SBT thin films without a variation in thickness were stably formed. That is, it was confirmed that the vaporizer for CVD of the first embodiment could stably form SBT thin films on the twenty silicon wafers without causing clogging in the vaporizer.
[0102] FIG. 3 is a diagram illustrating the result of an experiment that SBT thin films were formed on twenty silicon wafers by continuously operating the solution-vaporization type CVD apparatus, and the compositions of Bi, Ta, and Sr in the SBT film on each wafer were measured. According to the figure, it was confirmed that the SBT thin films having stable compositions of Bi, Ta, and Sr could be formed on the twenty silicon wafers.
[0103] As a result of conducting an experiment that the solution-vaporization type CVD apparatus having the vaporizer for CVD of the first embodiment was continuously operated to form an SBT thin film on a step, or in a recess portion or a groove was carried out, it was confirmed that the SBT thin film having a good step coverage could be formed. As a result of conducting an experiment that a high speed nonvolatile memory FeRAM utilizing the polarization phenomenon of SBT was fabricated by the solution-vaporization type CVD apparatus, it was possible to confirm that an extremely superior polarization characteristic of an SBT thin film was obtained. | The present invention relates to a vaporizer for CVD, a solution-vaporization type CVD apparatus and a vaporization method for CVD which suppress clogging of a solution pipe or the like and extend continuous operation times. A vaporizer for CVD of the present invention comprises a plurality of raw-material solution pipes which respectively supply a plurality of raw-material solutions separately from one another, a carrier gas pipe disposed in such a manner as to surround the exteriors of the raw-material-solution pipes and allows the pressurized carrier gas to flow to the exterior of each of the plurality of raw-material-solution pipes, an orifice provided in the leading end of the carrier gas pipe, and spaced away from the leading ends of the raw-material-solution pipes, a vaporization tube connected to the leading end of the carrier gas pipe and led to the interior of the carrier gas pipe via the orifice, and a heater which is heating means for heating the vaporization tube. | 2 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates to an apparatus for preventing deterioration of a rechargeable battery and regenerating the battery, that is, the apparatus for regenerating the battery by dielectrically heating and pulverizing an electrode non-conductor inactivating substance generated on the basis of discharge at a frequency of dielectric loss of the inactivating substance to effect electrochemical decomposition by charging current. The present invention also relates to an apparatus in which a dielectric heating current value obtained at the same time gives a storage quantity, that is, a quantity of dielectric dipole which is a quantity of the electrode non-conductor inactivating substance proportional to a discharged quantity is proportional to conductance at a peak frequency of dielectric loss, thereby knowing the discharge quantity, and the discharge quantity at the present time is deducted from a rated storage quantity to know a storage quantity which is a state of charge (SOC).
[0002] In a rechargeable battery, an electrode surface of the battery is covered with a thin film of an inactivating substance which is a poor conductor due to an increase in the number of times the battery is discharged. The thin film crystallizes with the elapse of time and crystallization results in electrical insulation of a charging channel which undergoes electrochemical decomposition by charging current. Recharge will not enable the regeneration of positive electrodes and negative electrodes, thus resulting in deterioration of storage capacity of the battery. Nowadays, with what is called smart grids which stabilize and store unstable electric power generated by natural energies such as sunlight and wing power, it is indispensable to prolong the service life of a rechargeable battery which is lower in price. In addition, it is necessary to provide technologies for preventing deterioration of storage capacity due to cycles of charge and discharge and regenerating the battery. Measurement of a storage quantity which is information on SOC is necessary for utilization of stored electricity.
[0003] Nowadays, as technologies for preventing deterioration of storage capacity of a rechargeable storage battery and regenerating the battery, there is known an apparatus which was granted and disclosed in Japanese Patent No. 4565362 to the applicant of the present invention in which, with restrictions placed only on prevention of deterioration of a lead acid battery and regeneration of the battery, a high-frequency electric current is allowed to flow, thereby fiving heating of dielectric loss to a layer of lead sulfate grown on an electrode surface to remove the insulation layer of lead sulfate. However, there have been so far filed no patents which cover technologies for preventing deterioration of rechargeable storage batteries in general and regenerating the batteries by automatically searching individual peak frequencies of dielectric relaxation loss or apparatuses for measuring remaining storage quantity.
[0004] The above document only deals with a lead acid battery, aiming at destruction of fine crystals of lead sulfate by using an apparatus for preventing deterioration of storage capacity of the battery and regenerating the battery or the apparatus for regenerating the battery by dielectrically heating and pulverizing electrode non-conductor inactivating lead sulfate crystals generated on the basis of discharge at a frequency of dielectric loss of the inactivating substance to effect electrochemical decomposition by charging current.
[0005] However, no measurement has been made for remaining storage quantity. There has been so far filed only a patent which is limited to a lead acid battery and deals with regeneration of the battery by dielectric heating decomposition and prevention of the deterioration thereof.
[0006] The present invention has been made in view of the above-described situation, an object of which is to provide an apparatus for measuring remaining storage quantity together with prevention of deterioration and regeneration of a rechargeable storage battery which can be applied to any type of the rechargeable storage battery. The present invention covers technologies for preventing deterioration of rechargeable storage batteries in general and regenerating the batteries by automatically searching individual peak frequencies of dielectric relaxation loss and an apparatus for measuring remaining storage quantity.
SUMMARY OF THE INVENTION
[0007] The cycle life of charge and discharge by a rechargeable battery is shortened by accumulation of an electro-chemical inactive insulator on electrodes. In general, an insulator undergoes dielectric relaxation loss and, for example, when a surface layer of lithium carbonate and that of alkyl lithium carbonate on a lithium ion battery are driven at a voltage of dielectric relaxation frequency, insulation crystals are thermo-mechanically distorted by dielectric loss heat, thereby forming fine cracks on the crystals to attain electric conduction, and electrochemical decomposition is caused by charging current, thus making it possible to regenerate and restore the storage capacity. An electrode surface which is not covered with an insulator is low in electric conductivity. This is because the electric conductivity on the surface of a metal electrode is mainly derived from ion diffusion current. And, since ion current is several hundred kHz or lower in response speed, the electric conductivity on the surface of a metal conductive electrode is small in a megahertz band of frequency of electricity storage inactivating dielectric relaxation. Therefore, at a high-frequency region, electric current will flow selectively in a concentrated manner on the surface of a high-frequency insulation layer high in dielectric rate.
[0008] A quantity of oxidized film insulator of an electrode by discharge is proportional to a quantity of discharge electricity according to Faraday's law of induction. In a dielectric heating current at a constant voltage which is driven cumulatively on charge, the number of chargeable dielectric dipoles which are not yet crystallized and the number of crystallized inactive dipoles are regarded as a quantity of high-frequency electric current to give conductance and also give a consumed storage quantity. That is, the number of dielectric dipoles which is a quantity of an electrode non-conductor substance proportional to a discharge quantity is proportional to conductance at peak frequencies of relaxation loss of both dielectric crystallization and non-crystallization dipoles, thereby knowing the discharged quantity, and the discharge quantity at the present time is deducted from a rated storage quantity to know a storage quantity. In a non-specific rechargeable battery, a peak frequency of dielectric relaxation loss is unknown. However, a high frequency at a constant voltage for driving dielectric relaxation loss is subjected to frequency sweeping during charge by direct current at a constant voltage or at a constant electric current, by which the most effective frequency at which an electro-chemical inactive insulator of the electrode undergoes decomposition of dielectric relaxation loss is known by referring to time when direct current on charge becomes maximum or a decrease in voltage on charge in the case of constant electric current. It is difficult to clearly know the time of complete charge when a substantial quantity of dark current flows during charge at a constant voltage even if a rechargeable battery is fully charged. Termination of complete charge is clearly indicated by the fact that charging current is not changed by connection or disconnection at a peak frequency for driving inactive dielectric relaxation loss. The state of charge, that is SOC, is able to accurately control invalid charging electricity charged by smart grids or others, clearly indicating a remaining storage quantity.
[0009] According to the present invention, an electro-chemical inactive insulation crystalline film of an electrode which prevents recharge of a rechargeable storage battery based on a non-specific principle is selected and subjected to thermo-mechanical fine decomposition. It is, therefore, possible to prevent semi-permanently deterioration of the rechargeable storage battery based on the none-specific principle by charge and discharge and also regenerate the battery. Specific information on termination of complete charge of a rechargeable battery is able to accurately control invalid charging electricity which is charged as dark current. Conductance at peak frequencies of relaxation loss of both dielectric crystallization and non-crystallization dipoles caused by discharge is strength of dielectric relaxation to provide information on a discharge quantity. The discharge quantity at the present time is deducted from a rated storage quantity to know an accurate quantity of remaining storage. Specific information on termination of complete charge and information on the accurate quantity of remaining storage are called a state of charge (SOC) and this is indispensable information on technologies of smart grids and others for utilizing rechargeable storage batteries.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] FIG. 1 is a block diagram which briefly shows an apparatus for preventing deterioration of a non-specific storage battery and regenerating the battery.
[0011] FIG. 2 is a drawing which shows characteristics of a leas silicate battery about a frequency of dielectric loss current.
[0012] FIG. 3 is a drawing which shows comparison in which the lead silicate battery is regenerated at a five-hour discharge rate.
[0013] FIG. 4 is a drawing which shows conductance of direct-current charge at a high frequency by regenerating the lead silicate battery.
[0014] FIG. 5 is a drawing which shows conductance at a high frequency by regenerating the lead silicate at a high frequency.
[0015] FIG. 6 is a drawing which shows conductance at a high frequency when a lithium ion battery is used.
[0016] FIG. 7 is a drawing which shows discharge characteristics of the lithium ion battery
[0017] FIG. 8 is a drawing which shows conductance at a high frequency when a nickel hydrogen battery is used.
[0018] FIG. 9 is a drawing which shows discharge characteristics of the nickel hydrogen battery.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0019] Hereinafter, a description will be given of one example as an embodiment of the present invention by referring to FIG. 1 to FIG. 9 .
Example 1
[0020] FIG. 1 is a block diagram which shows briefly an apparatus for preventing deterioration of a non-specific storage battery and regenerating the battery according to an embodiment of the present invention. This apparatus is provided with a microprocessor 21 (MPU) for controlling the apparatus for regenerating the storage battery, a charging voltage commanding D/A converter 22 by the MPU 21 , a charging voltage power amplifier 23 , a high-frequency cutoff coil 24 , a storage battery 25 , a storage battery terminal voltage measurement A/D converter 26 , a dielectric loss frequency sweeping synthesizer 27 , a dielectric loss frequency electric power amplifier 28 , a direct current cutoff condenser 29 , a charging current detector 30 , a dielectric loss frequency electric current detector 31 , a dielectric loss frequency electric current measurement A/D converter 32 , a charging current measurement A/D converter 33 , and a charging current returning channel 34 .
[0021] A lead silicate battery (12 volts) mounted on an electrically driven motorcycle discarded due to deterioration was regenerated by using the apparatus for preventing deterioration of the battery and regenerating the battery, the results of which are shown in FIG. 2 . In order to search a frequency of dielectric loss of lead silicate, a peak of dielectric conductance was searched.
[0022] A Curve 36 is a high-frequency dependent conductance curve for a lead silicate storage battery which is to be regenerated but not yet charged, and the curve has three peaks of dielectric loss 44 , 45 and 46 . A Curve 37 is a conductance frequency spectrum curve on ordinary charging by direct current, and the curve has peaks of dielectric loss 41 , 32 and 43 . A Curve 35 is a high-frequency dependent conductance curve for the lead silicate storage battery after being charged and regenerated which was obtained by automatically monitoring a frequency of dielectric loss. The peaks of dielectric loss 41 , 42 , 43 , 44 , 45 and 46 disappeared.
[0023] In a method for charging and regenerating a non-specific storage battery by automatically monitoring a frequency of dielectric loss, the A/D converter 26 is used to measure a voltage of the storage battery 25 and the voltage is input into the MPU 21 . Upon detection of a release voltage of the storage battery 25 which is equal to or lower than a predetermined value, the MPU 21 goes into a mode of regenerating the storage battery and produces a high-frequency electric current from the dielectric loss frequency sweeping oscillator 27 to amplify the current by the high frequency electric power amplifier 28 , thereby allowing a heating alternating current of dielectric loss to flow into the storage battery 25 via the direct current cutoff condenser 29 . The MPU 21 amplifies the current by using the electric power amplifier 23 from the D/A converter 22 and starts to charge the storage battery via the high frequency cutoff coil 24 , while monitoring a stipulated charging current by using the charging current detector 30 . The MPU 21 sweeps a frequency of dielectric loss, and constantly measures a charging current of the storage battery 25 to search a peak point of increasing the charging current. And, termination of decomposition of a charging inactivating substance by dielectric heating is when the charging current is kept unchanged by switching on or off the dielectric loss frequency electric power amplifier 28 . A determination on termination of complete charge of the battery for regeneration is made by subjecting all the frequency bands of dielectric loss to sweeping. Further, as apparent from FIG. 2 , a determination on termination of complete change of the battery for regeneration can be made by sweeping all the frequency bands of dielectric loss to confirm that peaks of dielectric relaxation have disappeared by using the dielectric loss frequency electric current detector 31 .
[0024] A Curve 44 in FIG. 3 shows a five-hour discharge rate by using only direct current as shown in the Curve 36 in FIG. 2 . Discharge is terminated in 3 hours and 50 minutes. The Greensaver SP27-12S is specified at 6.5 A/h for 32 A hr. A discharge Curve 45 after sufficient charge for regeneration by automatically monitoring a frequency of dielectric loss shows 5 hours 50 minutes, thus resulting in complete regeneration of the storage battery.
[0025] A Curve 46 in FIG. 4 is such that a lead silicate battery SP27-12S is repeatedly subjected to sweeping and loading at a high frequency from 1 MHz to πMHz during charge of 3 A constant electric current, thereby recording for 13 hours a difference in charging conductance when a high frequency is connected or disconnected. A straight line 47 obtained by a least-square method shows zero of high-frequency dependent conductance in 12 hours after the charge. This means that lead silicate which is a dipole has been completely reduced and charged, indicating clearly termination of the charge. Further, 3 A is multiplied by 12 hours to obtain 36 A hr charge. Discharge characteristics at 6.5 A constant electric current after charge for regeneration shown in FIG. 3 show 5.6 hours up to 10.5 V, and an actual storage quantity is about 36 A hr which is in good agreement. Thus, there is obtained effective information on termination of charge. Termination of complete charge in a rechargeable storage battery is clearly known from the fact that a charging current is kept unchanged when a peak frequency for driving inactive dielectric relaxation loss is connected or disconnected. Thus, there has been proposed an apparatus for accurately controlling invalid dark charge electricity to be charged.
[0026] A Curve 48 in FIG. 5 is such that a lead silicate battery SP27-12S is repeatedly subjected to sweeping and loading at a high frequency from 1 MHz to 90 MHz during 3 A constant electric current charge, thereby recording for 13 hours a high-frequency charging conductance which shows a dipole quantity. A straight line 49 obtained by a least-square method is such that the high frequency conductance is zero in 12 hour after the charge. This means that lead silicate which is a dipole has been completely reduced and charged, indicating clearly termination of the charge.
[0027] From the straight line obtained by the least square method, the number of both dielectric crystallization and non-crystallization dipoles which is a quantity of electrode crystalline and non-crystalline non-conductors proportional to a discharge quantity is proportional to conductance at a peak frequency of dielectric relaxation loss. Therefore, the discharge quantity is known and the discharge quantity at the present time is deducted from a rated storage quantity. It is, then, possible to propose an apparatus for outputting a remaining storage quantity which is a state-of-charge and a signal that indicates termination of complete charge, when both dielectric crystallization and non-crystallization dipoles are zero in conductance.
[0028] A Curve 50 in FIG. 6 is such that a lithium ion battery US18650 used in a discarded laptop computer is repeatedly subjected to sweeping and loading a high frequency from 1 MHz to 200 MHz during charge by a direct current constant at 0.2 A. A longitudinal axis shows a difference in charging conductance when a high frequency is connected or disconnected, with a unit of siemens. This is data obtained when the battery is substantially zero in remaining charge electricity. A horizontal axis indicates a high frequency applied cumulatively to direct-current voltage on charge.
[0029] FIG. 7 shows discharge characteristics of a lithium ion battery US18650 at 0.5 A on regeneration thereof. A longitudinal axis shows discharge voltage and a horizontal axis shows discharge time. A Curve 51 shows discharge characteristics of the battery which is fully charged only by direct current at a constant voltage of 4.5 V. A longitudinal axis shows voltage of the battery and a horizontal axis shows elapsed time after discharge. A Curve 52 shows a curve of discharge characteristics obtained when the battery is fully charged for regeneration at a high frequency. The battery is regenerated so as to substantially satisfy 1.28 A Hr specified by the US18650.
[0030] The results of FIG. 6 and FIG. 7 show that behavior similar to that of a lead silicate battery is found only by shifting a dipole vibration frequency of the lithium ion battery to a high frequency. It is, therefore, possible to estimate when the battery is fully charged and measure a remaining storage quantity.
[0031] A Curve 53 in FIG. 8 shows voltage and high-frequency dependent characteristics on charge at a constant current of 0.1 A which are observed in one of 20 nickel nitrogen batteries of an AMC 10V-UE battery pack used in a portable vacuum cleaner which was discharged. A longitudinal axis shows a difference in voltage with or without loads at a high frequency on charge at a constant current. A horizontal axis shows a frequency. A decrease in charging voltage resulting from the high frequency is found at a band from 80 MHz to 140 MHz and internal impedance on charge is decreased, which shows effective regeneration of electrodes by charge. It is understood that an inactivating dipole of salt which adheres on a hydrogen absorbing electrode is separated by dielectric heating to activate the electrode.
[0032] FIG. 9 shows discharge characteristics of a nickel hydrogen battery at 1 A. A Curve 55 shows discharge characteristics of the battery which is fully charged only by direct current constant-voltage of 1.5 V. A longitudinal axis shows a voltage of the battery, and a horizontal axis shows elapsed time of discharge. A Curve 54 shows discharge characteristics after charge at a constant current of 1 A at a high frequency as with the lithium ion battery. It is found that the battery has been restored up to a charging capacity of 2.9 A Hr as initially specified.
[0033] Lead acid batteries have been used extensively for starting engines of automobiles, marine vessels, etc., and also used as local storage stations of smart grids. They are also used in pulsation and rectification of wind turbine generators and solar batteries for utilizing natural energies. The present invention is capable of contributing to extension of cycle life of the storage batteries and made available accordingly.
DESCRIPTION OF REFERENCE NUMERALS
[0000]
21 : MPU (microprocessor) for controlling apparatus for regenerating storage battery
22 : Charging voltage commanding D/A converter by MPU 21
23 : Charging voltage power amplifier
24 : High frequency cutoff coil
25 : Storage battery to be regenerated
26 : Storage battery terminal voltage measurement A/D converter
27 : Dielectric loss high-frequency sweeping synthesizer
28 : Dielectirc loss high-frequency electric power amplifier
29 : Direct current cutoff condenser
30 : Charging direct-current detector
31 : Dielectric loss high-frequency electric current detector
32 : Dielectric loss high-frequency electric current measurement A/D converter
33 : Charging current measurement A/D converter
34 : Charging current returning channel
41 : High-frequency side peak of dielectric loss of lead silicate storage battery on charge by direct current at a constant voltage
42 : Intermediate frequency-side peak of dielectric loss of lead silicate storage battery on charge by direct current at a constant voltage
43 : Low frequency-side peak of dielectric loss of lead silicate storage battery which is not yet charged
44 : High frequency-side peak of dielectric loss of lead silicate storage battery which is not yet charged
45 : Intermediate frequency-side peak of dielectric loss of lead silicate storage battery which is not yet charged
46 : Low frequency-side peak of dielectric loss of lead silicate storage battery which is not yet charged | Provided is an apparatus in which an electrode insulation inactivating layer on the basis of charge and discharge which is a cause for deterioration of storage capacity of a rechargeable battery is regenerated by thermo-mechanical effects caused by dielectric relaxation loss, individual frequencies of dielectric relaxation loss of rechargeable batteries in general are automatically searched by an increase in high-frequency dependent charging current, the insulation layer is selectively decomposed, termination of charge of the storage battery is additionally known by connecting or disconnecting a frequency of dielectric relaxation loss, and electric current conductance at a frequency of dielectric relaxation loss gives a storage quantity which is a state of charge. | 7 |
BACKGROUND AND SUMMARY OF THE INVENTION
The invention relates to a method for the recovery of sediments from the bottom of the sea by means of a freely suspended suction pipe provided on one end with a suction mouth.
The invention further relates to apparatus for carrying out the method, comprising a floating body from which the suction pipe is suspended which carries at its lower end the suction head having attached thereto loosening means to dislodge the sediment to be recovered.
A prior art conveyor apparatus is known from German patent specification DE-OS No. 2 707 899, which includes a conveyor pipe the lower end of which is movable and in tightly fitting circumferential relationship with a cylindrical structure. Disposed between the cylinder and the end of the conveyor pipe is a drive means to reciprocate the two parts in an opposed motion. This reciprocating motion not only serves to produce a pumping action, but also produces high frequency vibrations. Such vibrations are intended to assist in the penetration of the mud to be conveyed and to prevent the creation of channels therein. This object, however, is achieved only partially achieved in actual practice.
The same disadvantage has been found in the conveyor apparatus according to the earlier German patent specification No. P 28 41 203.5 in which vibrations are generated in a similar fashion as in the afore mentioned well known device to loosen bottom formations. The vibratory movements are performed by a vibratory screen which may be in the shape of a cone pointing downward so that the direction of vibration is vertical. A device of this type is not capable of successfully loosening and dislodging relatively compact formations of mud-like consistency from the sea bottom as they occur, for instance, in the Red Sea at great depths. In any event, a device of this type is not capable of adequately loosening and dislodging sediment at any great depths in the sediment layers, but only near the less compacted surface of the sediment where the material is of a sufficient fluidity.
It is the object of the present invention to provide a method for the recovery of sediments by means of a freely suspended suction pipe by which sediments having the consistency of compacted mud can be recovered.
The object of the present invention is achieved by a method in which the suction means in the form of a suction mouth is successively slowly lowered into the sediment to be recovered, is raised up again to a height at which it is freely laterally movable, is laterally moved a predetermined distance, is lowered again, and so on, in a repeating cycle. The predetermined path of lateral movement is such that a lateral sliding of the suction mouth down into the depression formed in the sediment by the previous work cycle is avoided.
This teaching is based on the experience that vibrators do not produce a sufficiently effective loosening action. Moreover, the loosening effect of the well known prior suction heads provided with vibrators is limited to the area immediately surrounding the screen or to top layers of the sediment which are of a sufficiently low viscosity. Furthermore, the invention takes into account the fact that a lateral feed thrust, for instance in surface regions of the sediment which are of a satisfactory viscosity, will meet with difficulties at greater depths, such as for example 2000 meters. With this in mind, the method of the invention provides for the recovery operation or the forward thrust, respectively, to take place principally in the downward direction, by slowly lowering the suction mouth into the sediment, with the speed being so adjusted that the sediment portions in front of the suction mouth will be dislodged. In view of the high flow speeds in the region of the rims of the suction mouth, a loosening of even relatively compact mud-like formations is possible. Upon completion of the downwardly directed stripping action, which forms a more or less cylindrical to conical depression in the sediment, the method of the invention does not even attempt to continue the recovery operation in a sideways direction. Rather, the suction mouth is raised and is laterally moved a distance such that during the subsequent slow lowering of the suction mouth, any guiding forces in the sediment which may have been generated by the previous work cycle and which would cause the suction mouth to slide down into the previously formed depression, are rendered ineffective. Thus, it is insured that the suction mouth again is able to penetrate vertically into the sediment at the new location adjacent the previously worked depression to, thereby, form a new depression in the sediment to be recovered. In this manner, it is possible to expedite the penetration of the sediment by the suction mouth by using mass forces. By concentrating large masses in the suction head, considerable forces are realized enabling the suction head to penetrate also into relatively solid sediments and to loosen the material.
The lateral movement of the suction mouth attached to the suction pipe, which is freely suspended during the lateral movement, does not require a corresponding movement of the upper end of the suction pipe. Instead, it is sufficient to progressively move the upper end of the suction pipe sideways on the surface of the water, at a speed which corresponds to the mean lateral velocity of the suction mouth. During the lowering of the suction assembly into the sediment, the lower end of the suction pipe is guided in the respective depression so that small lateral forces due to the slightly sloping direction of the suction pipe caused by its steadily being advanced have no effect. When the suction pipe is raised to a height at which it is freely laterally movable, the lower end of the suction pipe having the suction mouth is, likewise, caused to move sideways due to the sloping condition of the suction pipe caused by the progresssive lateral movement, independent of the degree of such slope and the flow resistances prevailing at the suspended suction pipe, so that merely a predetermined period of time needs pass until the next work cycle is initiated, to ensure that the suction head has traversed the required distance. Consequently, notwithstanding the great lengths of the freely hanging suction pipe at a sufficiently controlled lateral movement of the floating body, it is possible to calculate with great precision the spacing of the depressions in the sea bottom sediment. Acoustic positioning means may be used to control the operation.
To assist the suction mouth in the penetration of the sediment, the invention provides for mechanical drilling, stripping or scraping means attached to the suction mouth, which means are rotated during the lowering and/or lifting of the suction mouth. Such rotational movement can be accomplished without difficulty by rotating the entire suspended suction pipe on the surface of the sea so that any special drive means for the suction mouth, as they are for instance required in the prior art vibratory suction heads, can be dispensed with, which represents a considerable advantage when working in great depths and, in addition, at high temperatures as is the case, for example, in the Red Sea.
The invention also provides for apparatus for carrying out the method. Such apparatus comprises a floating body from which the suction pipe is suspended which has attached to its lower end the suction head provided with means for loosening the sediment. In accordance with the invention, such loosening means are so constructed that they exert only a low degree of frictional resistance with respect to the sediment when lowered into it, while they exert a high degree of frictional resistance when they are extricated from the sediment. This particular type of construction takes into consideration the fact that as the suction mouth is penetrating into relatively solid sediment layers, there is danger of lateral deflection or buckling of the suspended suction pipe hitting the formation. For this reason, the frictional resistance is kept low during penetration into the sediment, whereby such deflections are avoided. Conversely, when the suction assembly is lifted, the large loosening forces may come into their own without disadvantage.
Loosening means which have the mentioned properties may be of a variety of types. They may for instance comprise a worm which is freely rotatably mounted at the lower end of the suction pipe and, as it is being lowered, drills into the sediment, while during the lifting stroke, forces are operative which prevent a rotation of the worm. Consequently, the sediment in the area surrounding the suction head is dislodged or loosened in large scale like fragments. However, the worm may also be fixedly mounted on the suction pipe, and the desired rotation of it may be brought about by a corresponding rotation of the upper end of the suction pipe on the surface of the sea.
Another form of construction that the loosening means may take is that of a folding anchor which will open up during lifting so that the surrounding sediment will be gripped and pulled up in large scales.
As the suction head and loosening tool assembly is being raised, generating a great amount of frictional resistance in accordance with the invention, an area of reduced pressure is produced below the loosening tools. This feature is utilized by a further development of the invention, in that the suction head is provided below the loosening means having high frictional resistance values, e.g. flukes or pivot plates, with nozzles pointing downwardly or preferably sideways. Such nozzles are in communication by way of a channel with entry openings which are located at a sufficient height above the means having large frictional resistance values, e.g. the flukes or pivot plates. The reduced pressure thus generated has the effect that water is caused to rush into this area, precipitating a flushing and loosening process which continues during the entire extent of the upward movement.
The sediment in its upper layers frequently has a viscosity which is amenable to pumping. Moreover, during working the sediment, a cloud of whirling sediment particles is produced immediately above the sediment surface. To aid in the flushing process going on in the region below the loosening means and to augment its effect, water is used by suction action from the mentioned cloud of sediment particles or from fluid layers of sediment. Arranging the suction openings at fixed locations on the suction pipe may entail the probability that they are too high up, resulting in the undesirable admission by suction of sediment-free water.
To remedy this situation, according to a further embodiment of the invention, the entry openings are spread out over an extended vertical stretch of the suction pipe. A vertically movable cover pipe is arranged over the suction pipe to cover this spread. The cover pipe is provided with means for its height adjustment. This height adjustment may be effected in the simplest case by a rope hanging from a spot above the surface of the sea. It is preferred, however, to have such height adjustment means comprise floating bodies, whereby the total buouancy of the cover pipe and floating bodies is so adjusted that the cover pipe is maintained floating in a fluid layer of predetermined density. This type of assembly is capable of accommodating varying heights as, for example, in the case of a funnel-shaped depression the depth of which is slowly increasing while the level of essentially sediment-free water is decreasing.
Another form of the means for height adjustment of the cover pipe consists of supporting surface areas for engagement by the side edges or rims of the hole or funnel formed in the sediment. As the funnel-shaped depression in the sediment is widened and deepened, the supporting surface areas will follow the changing configuration and, thus, effect a lowering of the height of the cover pipe.
BRIEF DESCRIPTION OF THE DRAWINGS
Further objects and features of the invention will be described with reference to an illustrative embodiment as shown in the accompanying drawings, in which:
FIG. 1 is a schematic representation of the principles underlying the method of the invention;
FIG. 2 is a perspective view of the suction head of the invention;
FIG. 3 is a side elevational view, partly in section, and enlarged, of a suction head provided with a worm for use in accordance with the method of the invention; and
FIG. 4 is a sectional view of a folding anchor type suction head provided with flushing nozzles and means for the height adjustment of suction openings.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the largely schematic illustration of FIG. 1, a ship 1 is positioned on the surface 2 of a body of sea water 3. Extending downwardly from the ship 1 is a conveyor pipe 4, the lower section of which has mounted thereon a pump 5 from which a suction pipe 6 leads to a suction head 7 provided with a suction mouth 8. The suction head is illustrated in greater detail in FIGS. 2 and 3.
The conveyor pipe 4 is suspended from the ship 1 by means of a suspension structure 9. The suspension structure 9 is supported on two hydraulic cylinders 10 which move the conveyor pipe 4 and the members attached thereto, in particular the suction head 7, up and down as indicated by the arrows 11 and 12. The hydraulic cylinders 10 are biased by a gas pressure storage container 10'.
Located in the bow of the ship 1 is a drive means which together with the drive means 14 in the ship's stern serve to maintain the ship in directional alignment with respect to the vertical axis. Further provided in the rear of the ship is a screw propeller 15 by which the ship is slowly and steadily advanced in the direction of the arrow 16.
In employing the method according to the invention, the hydraulic cylinders 10 are so actuated in the direction of the arrow 12 that the suction head 7 is caused to be lowered into a sediment composed of two layers 17 and 18. The layer 17 has a viscosity such that the suction head 7 is freely laterally movable therein. The more compact layer 18 is penetrated by the suction head 7 owing to the weight of the suction head 7 to form a depression 19 in the shape of an ordinary hole or a funnel, depending on the nature of the sediment. The depth of the depression 19 may extend approximately to the region of the lower boundary of the layer 18, subject to the prevailing forces and the nature of the layer 18. Disposed below the layer 18 is a geological formation that does not warrant recovery.
The cylinders 10 are then actuated in a manner as to cause the conveyor pipe 4 having the suction head 7 fastened thereon to be lifted again. Both during the lowering and, particularly, the lifting operation, the conveyor pump 5 becomes effective to enable the suction head to convey by suction volumes of sediment of mud-like consistency from the depression 19. Depressions 19' produced in previous operations are indicated to the left of the depression 19 in FIG. 1.
When the suction head 7 on the upstroke reaches the layer 17 in which it is freely laterally movable in the direction of the arrow 16, the suction head 7 will be moved a distance in the direction of the arrow 16 such as to ensure that at the next downward stroke a new depression 19 is formed. The spacing between two depressions will be seen from a comparison of the depressions 19 and 19'.
The lateral movement of the suction head 7 is effected by a progressive movement of the ship 1 by means of its screw propeller 15, with the result that the conveyor pipe 4 will hang slightly tilted, not shown in the drawing, so that the suction head 7 has a tendency to drift sideways in the direction of the arrow 16. On reaching the layer 17 during the upward movement, the suction head 7 may tend to follow this pull and move off in the direction of the arrow 16, in dependence upon the magnitude of the lateral sag and the flow resistance of the other members immersed in water. However, at a constant movement of the ship 1 and by properly controlling the hydraulic cylinders 10 from the completion of the upward stroke to the renewed lowering of the suction assembly, it is only necessary to wait a predetermined period of time to ensure that the suction head has moved a predetermined distance in the desired direction as indicated by the arrow 16. The setting of the constant speed of the ship 1, the lateral sag of the conveyor pipe 4 and the time interval between the completion of the lifting and the resumption of the lowering action may be determined in accordance with tests performed on the material recovered, or by performing ultrasonic measurements of the respective positions of the suction head 7.
The suction head 7, which is shown in a perspective view in FIG. 2 and in an elevational side view, partly in section, in FIG. 3, comprises vertically extending guide plates 21 which are secured to the lower end of the suction pipe 6. The free space defined by the guide plates 21 holds a vertically disposed rod 22 which serves as a pivot bearing for a cylindrical screen 23. The screen 23 is also vertically movable on the rod 22 and is downwardly biased by a spring 24 such that, without exerting any force, it may assume a position as indicated by the broken line 25. In this position, projections 26 provided on the screen 23 will be in engagement with stationary recesses 27 to secure the cylindrical screen 23 against rotary movement.
Disposed on the cylindrical screen 23 is a worm 28 extending laterally beyond the projections of the suction pipe 6. The worm 28 is adapted to drill into a mud-like sediment, as the suction head is lowered, by rotating about the shaft 22 in a position indicated by full lines in FIG. 3, i.e. with the spring 24 compressed and the projections 26 released from the recesses 27. When the suction head 7 is raised again, the screen 23 on the rod 22 moves downward so that the projections 26 again will engage the recesses 27 to lock the worm in position against rotary motion. In this position the worm represents a major force of frictional resistance by which the surrounding sediment is disloged, thrust upwardly and loosened so that recovery by suction can take place. The suction action is further enhanced by the action of the flushing nozzles 29.
FIG. 4 illustrates another embodiment of a suction head which is in the nature of a folding anchor. A shank or pipe 30 closed on top (not shown) constitutes at its lower end 31 a suction mouth provided with a multiplicity of small suction openings which are in communication with a suction pipe 33. The lower end of the pipe 30 is provided with flukes 34 pivotable about pins 35 so as to be pivoted from the folded rest position, as indicated in full lines, into an operative position indicated by dashed lines 34'. In the operative position, the flukes 34 are secured against excessive pivotal movement by extensions 36 which abut against stops 37.
The flukes are provided with outwardly bent end sections 38 to enable the flukes to pivot outwardly as the device is pulled up, thereby producing a great amount of frictional resistance by which the surrounding sediment is dislodged and loosened.
Disposed below the flukes 34, 34' are nozzles 39 which are in communication by a channel 40 with entry openings 41. The openings 41 are arranged above the level of the flukes 34. The entry openings are spread out over a considerable vertical stretch on the pipe 30, which however, is not particularly shown in the drawing for simplicity's sake. This is also true of the distance of the entry openings 41 above the flukes 34. In actual practice, this distance may amount to many meters, depending on the prevailing density or viscosity gradients in the sediment layers 17 and 18 in FIG. 1.
A tubular vertically movable cover pipe structure 42 is provided to cover part of the entry openings 41 on the pipe 30. The drawing shows the lowest position of the cover pipe 42 in relation to the pipe 30, with the cover pipe 42 resting on ledges 43.
The cover pipe 42 is further provided with a plate 44 having buoyancy means 45 thereon, for example in the form of glass spheres. The buoyancy capacity is so dimensioned that, as a function thereof, the assembly consisting of the cover pipe 42, the plate 44 and the buoyancy body 45 is maintained floating at a certain height in the surrounding medium of defined density so that the entry openings 41 are covered. With decreasing density of the surrounding medium, such as water, for example, the cover pipe 42 will be moved downward to cover the corresponding entry openings 41 to prevent the entrance of sediment-free seawater.
It will be understood that the embodiments of the present invention which have been described are merely illustrative of a few applications of the principles of the invention. Numerous modifications may be made by those skilled in the art without departing from the true spirit and scope of the invention. | In a method and apparatus for the recovery of sediments from the sea bottom, a suction head having a mouth is lowered into the sediment, raised from the sediment to form a depression, laterally moved to a new location adjacent the first depression, and the cycle is repeated to form a new depression. The suction head includes loosening means in the form of a worm or flukes which exert a low frictional resistance with respect to the sediment during lowering of the suction head and high frictional resistance when the head is being raised from the sediment. | 4 |
This is a continuation of application Ser. No. 06/947,296 filed Dec. 29,1986.
FIELD OF THE INVENTION
The present invention relates to an antifouling coating that contains a polymer having polydimethylsiloxane groups and/or trimethylsilyl groups in side chains.
BACKGROUND OF THE INVENTION
The bottoms of ships, buoys and other structures that are submerged in seawater such as cooling water intake or discharge pipes are infested with organisms such as barnacles, tube worms, mussels and algae that attach to the surfaces of these structures and cause various troubles. It is routine practice to prevent the attachment of these marine organisms by coating the surface of the aforementioned items with antifouling paints. Antifouling paints are roughly divided into two classes. The antifouling paints of one class (A) employ antifoulants such as organotin copolymers and cuprous oxide that are capable of preventing the attachment of fouling organisms and have low solubility in seawater. Paints that employ organotin compounds as antifoulants are shown in Japanese patent Publication Nos. 21426/65, 9579/69, 13392/71, 20491/74, 11647/76 and 48170/77. The antifouling paints of the second class (B) do not employ any antifoulants and will not dissolve in seawater; instead, they use silicone rubbers that cure by the action of a catalyst or moisture to form a crosslinked film. For instance, an antifouling paint that uses a curable silicone rubber as a coating agent is shown in Japanese patent Publication No. 5974/78. An antifouling paint that uses a mixture of a silicone oil and an oligomer-like silicone rubber having a terminal hydroxyl group is shown in Japanese patent application (OPI) No. 96830/76 (the term "OPI" as used herein refers to a "published unexamined Japanese patent application"). A mixture of a curable silicone rubber and a flowable organic compound that does not contain a metal or silicon is shown in Japanese patent application (OPI) No. 79980/78. A paint that serves to prevent the attachment of fouling marine organisms is also shown in Japanese patent Publication No. 3433/85 and this paint is composed of a mixture of an oligomer-like low temperature curing silicone rubber (such as ones available from Shin-Etsu Chemical Co., Ltd. under the trade names of "KE 45TS" and "KE 44 RTV") and liquid paraffin or petrolatum.
The antifouling paints of class (A) are further divided into two subclasses. In one subclass of such antifouling paints, the film-forming resin does not dissolve in seawater and only the antifoulant dissolves in seawater to prevent the attachment of marine organisms. The coatings formed from this class of antifouling paints exhibit the intended effect during the initial period of application but after the antifoulant on the surface of the coating is lost as a result of its dissolution in seawater, the antifoulant in the deeper area of the coating will gradually dissolve. However, the dissolution rate of the antifoulant decreases as the depth of the area in which it is present in the film of coating increases, and the antifouling effect of the paint becomes insufficient in the long run.
In the second subclass of antifouling paints of class (A), both the antifoulant and the film-forming resin dissolve in seawater. The antifouling effect is achieved solely by the antifoulant or by a combination of the antifoulant and the resin component (e.g., an organotin copolymer) and, in either case, the surface of the coating dissolves in seawater to continuously provide the antifouling film of coating with an active surface. Therefore, the coating formed from this type of antifouling paints is capable of maintaining the desired antifouling effect over a longer period than the aforementioned first subclass of paints (A). However, the effect of this type of antifouling paints is not completely satisfactory because the film of coating they form is consumed fairly rapidly. In addition, the antifouling paints that employ antifoulants have one common problem in that the antifoulants have a potential for polluting the sea and killing marine products such as fish and shells.
Antifouling paints of class (B) are designed to prevent the attachment of marine organisms by making use of the slipping property (low surface energy) of the silicone rubber coating. However, these paints have the following disadvantages associated with the mechanism of film formation that involves the crosslinking of silicone rubbers after paint application.
The first problem is associated with the curing of the applied coating. For instance, when an antifouling paint of the type described in Japanese patent Publication No. 3433/85 that employs a low temperature curing oligomer-like silicone rubber that cures by the action of moisture in air to form a film of coating is applied to a substrate, the crosslinking agent incorporated to control the curing condensation reaction of the silicone rubber is activated by the moisture or temperature of air to cause premature curing of the surface of the coating. This retards the curing of the deeper portion of the coating to produce an insufficiently cured film which is most likely to blister or separate from the substrate. Furthermore, the slow penetration of moisture into the bulk of the coating prolongs the time required to achieve complete curing of the coating.
If the antifouling paint of the type described above is applied in a hot and humid atmosphere, the hydrolysis of the crosslinking agent predominates over the crosslinking reaction and the resulting coating does not have a sufficient crosslink density to provide satisfactory properties.
In a dry climate, the amount of aerial moisture is too small to cause hydrolysis of the crosslinking agent and the applied coating will cure very slowly. In order to avoid this problem, catalysts such as tin compounds and platinum are sometimes used as curing accelerators but their effectiveness is limited in cold climates.
The second problem concerns the case of top-coating. In the usual case, the solvent in a paint for topcoating slightly dissolves the surface of the undercoat to ensure good intercoat bonding. However, in the application of the antifouling paint under consideration, the silicone rubber in the first applied coating cures to such an extent that the solvent in a paint for top-coating is not capable of dissolving the surface of the silicone rubber to provide satisfactory intercoat bonding.
The third problem is related to pot life. The actual coating operation is prolonged if the item to be treated is large in size or has a complex structure. In addition, the operation may be interrupted by unexpected rainfall. In view of these possibilities, antifouling paints having short pot lives present great inconvenience in coating operations.
The fourth problem is associated with storage stability. Antifouling paints, after being prepared, are stored until use and the duration of such storage sometimes extends for a long period. Therefore, the manufacture of paints that will cure by the action of moisture necessitates the filling of their containers with a dry nitrogen gas. In addition, once the container is opened, aerial moisture will get into cause curing of the surface of the paint or an increase in its viscosity. Paint that has undergone such changes is no longer suitable for use.
SUMMARY OF THE INVENTION
The present inventors made concerted efforts to develop an antifouling coating that possesses none of the aforementioned disadvantages of the conventional products and which yet exhibits superior antifouling effects. As a result of these efforts, the inventors have succeeded in creating an effective antifouling coating that does not use any antifoulant but uses a specified polymer of the type which dries by solvent volatilization and which has polydimethylsiloxane groups and/or trimethylsilyl groups in side chains. Unlike the silicone rubber described above in connection with the prior art, the polymer specified by the present invention dries by solvent volatilization and hence is inherently free from the problems associated with curing processes, cohesion of interlayers, pot life and storage stability. What is more, the film formed from this polymer provides a superior surface slipping property to ensure improved antifouling effects.
The present inventors have also found that further improvements in antifouling effects can be achieved by incorporating a slipping agent such as petroleum waxes, silicone oils, fats and oils in the specified polymer.
An object, therefore, of the present invention is to provide an industrially useful antifouling coating that solves all of the problems associated with the conventional antifouling paints and which yet achieves much better antifouling effects.
In order to achieve this object, the present inventors conducted intensive studies and have succeeded in preparing an antifouling coating that is based on a polymer of the type which dries upon solvent volatilization. This coating is free from all of the defects of the known antifouling paints which employ a silicone rubber either alone or in combination with a silicone oil or paraffin and yet produces a coating surface that has a small enough angle of slip to exhibit better antifouling effects.
The antifouling coating of the present invention contains as its essential components a polymer of one or more of the monomers A represented by formula (1) and/or a copolymer which is composed of one or more of the monomers A and one or more monomers B that are radical-copolymerizable with said monomer A: ##STR2## wherein X is a hydrogen atom or a methyl group; n is an integer of 2 to 4; and m signifies the average degree of polymerization and ranges from 0 to 70.
If this polymer (hereinafter designated as polymer A) or copolymer (hereinafter designated as copolymer AB) is used in combination with a specified slipping agent, a further improvement in the antifouling effects of the coating can be achieved without sacrificing the advantages resulting from the use of polymer A or copolymer AB.
BRIEF DESCRIPTION OF THE DRAWING
FIGS. 1(A) and (B) are side views showing how to measure the slip angle of the surface of the antifouling coating film.
DETAILED DESCRIPTION OF THE INVENTION
Monomer A used in the present invention for preparing polymer A or copolymer AB is an unsaturated monoester represented by formula (1) which has a polydimethylsiloxane group (m>1) or a trimethylsilyl group (m=0) in the molecule. In formula (1), m is specified to be within the range of 0 to 70; if m is greater than 70, the polymerizability or copolymerizability of monomer A is decreased to an extent which renders it difficult to attain polymer A or copolymer AB in a form that is capable of producing a uniform film of coating. In formula (1), n is specified to be within the range of 2 to 4. If n is less than 2, the linkage at the esterforming portion of monomer A becomes weak and during polymerization or during the use of the resulting coating the ester linkage dissociates to either reduce the antifouling effect of the coating or shorten the duration of time during which it exhibits the intended antifouling effect. If n is more than 4, the polymer becomes too soft to form a satisfactory film of coating.
Examples of the monomer A represented by formula (1) are hereinafter listed by their specific names: illustrative compounds having a trimethylsilyl group include trimethylsilylethyl acrylate or methacrylate, trimethylsilylpropyl acrylate or methacrylate, and trimethylsilylbutyl acrylate or methacrylate; illustrative compounds having a polydimethylsiloxane group include polydimethylsiloxanethyl acrylate or methacrylate (m≦70), polydimethylsiloxanepropyl acrylate or methacrylate (m≦70), and polydimethylsiloxanebutyl acrylate or methacrylate (m≦70).
These compounds as examples of monomer A are readily available commercially or can be attained by synthesis. Exemplary methods of synthesis include: a method wherein acrylic acid or methacrylic acid is reacted with an alkylene glycol to form a corresponding ester, which then is condensed with a trimethylsilyl or polydimethylsiloxane compound; and a method wherein an ester of acrylic or methacrylic acid with an allyl alcohol is subjected to an addition reaction with a trimethylsilyl or polydimethylsiloxane compound.
Monomer A may be copolymerized with a radical polymerizable monomer B to form copolymer AB, and illustrative compounds that can be used as monomer B include: methacrylate esters such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, and 2-hydroxyethyl methacrylate; acrylate esters such as ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, and 2-hydroxyethyl acrylate; maleate esters such as dimethyl maleate and diethyl maleate; fumarate esters such as dimethyl fumarate and diethyl fumarate; and styrene, vinyltoluene, α-methylstyrene, vinyl chloride, vinyl acetate, butadiene, acrylamide, acrylonitrile, methacrylic acid, acrylic acid and maleic acid.
Radical polymerizable monomer B serves as a modifying component that imparts desirable properties to the antifouling coating; this monomer is also useful for the purpose of attaining a polymer that has a higher molecular weight than the homopolymer of monomer A. The amount of monomer B used is appropriately determined in consideration of the properties it imparts and the antifouling effect achieved by monomer A. Generally, the ratio of monomer B is not more than 90 wt%, preferably not more than 70 wt%, of the total amounts of monomer A and monomer B. The reason for selecting this range is that if the proportion of monomer A in copolymer AB is at least 10 wt%, especially at least 30 wt%, the intended antifouling effect can be satisfactorily achieved by monomer A.
Polymer A or copolymer AB may be formed by polymerizing monomer A either alone or in combination with monomer B in the presence of a radical polymerization initiator in accordance with routine procedures. Methods of polymerization include solution polymerization, bulk polymerization, emulsion polymerization and suspension polymerization. Illustrative radical polymerization initiators are azo compounds such as azobisisobutyronitrile and triphenylmethylazobenzene, and peroxides such as benzoyl peroxide and di-tert-butyl peroxide.
The polymer A and copolymer AB to be prepared by the methods described above preferably have weight average molecular weights within the range of 1,000 to 150,000. If the molecular weight of the polymer A or copolymer AB is too low, it is difficult to form a dry uniform film. If the molecular weight of polymer A or copolymer AB is too high, it makes the varnish high viscous. Such a high viscosity varnish should be thinned with a solvent for formulating a coating. Therefore, the resin solids content of the coating is reduced and only a thin dry film can be formed by a single application. This is inconvenient in that several applications of coating are necessary to attain a predetermined dry film thickness.
In accordance with the present invention, a slipping agent may be used in combination with polymer A and/or copolymer AB. Any compound may be used as this slipping agent so long as it is capable of substantially maintaining or lowering the small angle of slip that is possessed by the surface of the film of coating formed from the polymer A and/or copolymer AB. The following five classes of materials that impart slip properties to the film of coating may be used as slipping agents in the present invention.
(1) petroleum waxes of the class specified in JIS K 2235, which include paraffin wax e.g., having a melting point of from about 48.9° C., microcrystalline wax e.g., having a melting point of about 60° C. or over and petrolatum e.g., having a melting point of from about 45° C. to 80° C.;
(2) liquid paraffins of the class specified in JIS K 2231, which are illustrated by equivalents to ISO VG 10, ISO VG 15, ISO VG 32, ISO VG 68, and ISO VG 100 e.g., having a kinetic viscosity of from about 9 to 110 centistokes at 40° C.;
(3) silicone oils having kinetic viscosities of not more than 55,000 centistokes (cSt) at 25° C., which are illustrated by those available from Shi-Etsu Chemical Co., Ltd. under the trade names of KF 96 L-0.65, KF 96 L-2.0, KF 96-30, KF 96 H-50,000, KF 965, KF 50, KF 54 and KF 69; dimethyl silicone oil is most common but other silicone oils such as methylphenyl silicone oil may also be used;
(4) fatty acids or esters thereof having melting points of -5° C. or higher and not less than 8 carbon atoms; illustrative fatty acids that satisfy these requirements include caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, cerotic acid, montanic acid, melissic acid, lauroleic acid, oleic acid, vaccenic acid, gadoleic acid, cetolic acid, selacholeic acid, and juniperic acid; illustrative esters of these fatty acids include stearyl stearate, butyl laurate, octyl palmitate, butyl stearate, isopropyl stearate, cetyl palmitate, ceryl cerotate, myricyl palmitate, melissyl melissate, spermaceti, bees wax, carnauba wax, montan wax, Chinese insect wax, tristearin, tripalmitin, triolein, myristodilaurin, caprylolauromyristin, stearopalmitoolein, monostearin, monopalmitin, distearin, dipalmitin, tallow, lard, horse fat, mutton fat, cod-liver oil, coconut oil, palm oil, Japan tallow, Kapok oil, cacao butter, Chinese vegetable tallow, and illipe butter;
(5) organic amines having an alkyl or alkenyl group containing 12 to 20 carbon atoms, such as dodecylamine, tetradecylamine, hexadecylamine, octadecylamine, oleylamine, tallow alkylamines, coco-alkylamines, soybean alkylamines, didodecylamine, di-tallow-hydrogenated alkylamines, dodecyldimethylamine, coco-alkyldimethylamine, tetradecyldimethylamine, hexadecyldimethylamine and octadecyldimethylamine.
The slipping agents specified above are used in amounts that should be properly determined in consideration of the drying properties, adhesion to substrate and antifouling effects offered by the polymer A and/or copolymer AB. Generally, the slipping agents are used in amounts of 1 to 70 wt%, preferably 5 to 50 wt%, of the total amount of polymer A and/or copolymer AB and the slipping agent.
As will be apparent from the foregoing description, the antifouling coating of the present invention is typically used in the form of a solution wherein polymer A and/or copolymer AB together with the slipping agent specified above are dissolved in an organic solvent. Therefore, practical considerations indicate that it is preferred to prepare polymer A and/or copolymer AB by solution polymerization or bulk polymerization.
Examples of the organic solvent that can be used to prepare a solution of polymer A and/or copolymer AB which optionally contains the slipping agent include: aromatic hydrocarbons such as xylene and toluene; aliphatic hydrocarbons such as hexane and heptane; esters such as ethyl acetate and butyl acetate; alcohols such as isopropyl alcohol and butyl alcohol; ethers such as dioxane and diethyl ether; and ketones such as methyl ethyl ketone and methyl isobutyl ketone. These organic solvents may be used either alone or in admixture.
The organic solvents are preferably used in such amounts that the concentration of polymer A and/or copolymer AB in the solution generally ranges from 5 to 80 wt%, preferably from 30 to 70 wt%. The solution preferably has a viscosity of 1 to 10 poises at 25° C. in order to facilitate the film formation from the solution.
The antifouling coating of the present invention thus prepared may optionally contain colorants that are intoxic and will not dissolve in seawater. Suitable colorants are pigments such as red oxide and titanium dioxide, and dyes. The coating agent may also contain conventional antisagging agents, antiflooding agents, antisetting agents, and antifoaming agents.
The surfaces of structures to be submerged in seawater are treated with the antifouling coating of the present invention to form an antifouling film of coating. The procedure cf such treatment is simple; for instance, a solution of the coating is applied to the surface of the structure of interest by an appropriate means and the solvent is removed by evaporation at ordinary temperatures or under heating. This suffices for the purpose of forming a uniform film of antifouling coating that exhibits good slip properties.
The polymer A and/or copolymer AB used in the present invention has the polydimethylsiloxane group and/or trimethylsilyl group that derives from monomer A and because of these groups, the polymer A or copolymer AB is capable of forming a film of coating that has a very slippery surface. Therefore, the film itself of the coating formed from such polymer or copolymer has the ability to physically prevent the attachment of fouling marine organisms.
Radical polymerizable monomer B in copolymer AB serves as a modifying component that imparts an adequate level of slip properties to the surface of the film of coating formed from copolymer AB. Monomer B is also effective in forming a polymer having a higher molecular weight than a homopolymer of monomer A or in controlling the hardness and strength of the film of coating.
The slipping agent which may be used in the present invention in combination with polymer A and/or copolymer AB is an important component since the combination ensures prolonged antifouling effects in a marine environment where the growth of fouling organisms is active. The present inventors consider that this enhanced retention of antifouling effects is due to the maintained slip properties of the film of antifouling coating that is achieved by the surface lubricating action of the slipping agent and by the ability to retard the deterioration of the film formed from polymer A and/or copolymer AB.
The polymer specified in the present invention for use in an antifouling coating is inert and forms a thermoplastic film of coating that dries upon solvent volatilization and which is insoluble in seawater. Therefore, the antifouling coating of the present invention has the following advantages over the conventional antifouling paints.
First, it is stable and can be formulated in a paint without experiencing any risk of deterioration by reaction with other active ingredients. The container of the paint does not need to be filled with an inert gas because it has an unlimited pot life.
Secondly, the paint dries quickly after application and yet will not blister or separate from the substrate because it will not experience any inadequate curing in the deeper area of coating and the drying speed is not affected by moisture or temperature.
Thirdly, the film of coating formed from the coating of the present invention can be topcoated with a similar or dissimilar paint without sacrificing the strength of intercoat bonding.
Fourthly, the film formed from the coating of the present invention will not be eroded by contact with seawater and therefore retains good antifouling effects over a prolonged period. The superior antifouling effects of the film are supported by the fact that its surface has an angle of slip that is much smaller than that exhibited by the film of coating formed from the conventional antifouling paint employing a crosslinked silicone rubber.
The present invention is hereinafter described in greater detail with reference to the following examples of polymer preparation, working examples and comparative examples, wherein all parts are on a weight basis. The data for viscosity were obtained by the measurement of bubble viscosities at 25° C., and the data for molecular weights are indicated in terms of weight average molecular weights as measured by GPC (gel permeation chromatography).
PREPARATION EXAMPLES 1, 2, 4, 5 AND 7 TO 9
A flask equipped with a stirrer was charged with a cooking solvent a (for its name and amount, see Table 1), which was heated to a predetermined temperature for reaction. A liquid mixture of monomer A, monomer B and a radical polymerization initiator a (for their names and amounts, see Table 1) was introduced dropwise into the flask with stirring over a period of 2 to 3 hours. After completion of the addition, the contents of the flask were held at the predetermined temperature for reaction for a period of 30 minutes. Subsequently, a mixture of a cooking solvent b and a radical polymerization initiator b (for their names and amounts, see Table 1) was added dropwise over a period of 20 hours, and the resulting mixture was held at the predetermined temperature for 3 to 5 hours with stirring so as to complete the polymerization reaction. Finally, a solvent was added to dilute the reaction product. By these procedures, copolymer solutions I, II, IV, V, VII to IX were prepared.
PREPARATION EXAMPLES 3 AND 10
A heat- and pressure-resistant vessel was charged with a monomer A, monomer B and a radical polymerization initiator a in accordance with the formulations shown in Table 1. The vessel was completely closed and the contents were heated to a predetermined temperature for reaction under shaking. Thereafter, the shaking of the vessel was continued for 2 hours until polymerization reaction was completed. A diluting solvent was then added and shaking was continued for an additional 3 hours to obtain a solution. By these procedures, copolymer solutions III and X were prepared.
PREPARATION EXAMPLE 6
A flask equipped with a stirrer was charged with a cooling solvent a, a monomer A and a radical polymerization initiator a and the contents of the flask were heated to a predetermined temperature for reaction with stirring. The stirring of the reaction mixture was continued at the predetermined temperature for 3 hours to obtain a copolymer solution VI.
TABLE 1__________________________________________________________________________ Preparation ExampleComposition (parts) 1 2 3 4 5 6 7 8 9 10__________________________________________________________________________Cooking Solvent aButyl acetate 120 180 30 180Xylene 50 15 100 120Ethylene glycol monoethyl ether 45Monomer A (*1) 120 180 55 15 25 100 36 120 180 13(See Note below for its structure)(x) (CH.sub.3) (CH.sub.3) (CH.sub.3) (H) (CH.sub.3) (CH.sub.3) (CH.sub.3) (CH.sub.3) (CH.sub.3) (CH.sub.3)(n, m) (3, 10) (3, 3) (3, 10) (2, 70) (4, 30) (3, 0) (3, 20) (1, 8) (5, (3, 75)Monomer BMethyl methacrylate 120 169.2 45 85 58 72 120 150 87Ethyl acrylate 10.8Methacrylic acid 2Butyl acrylate 5Styrene 10Butyl methacrylate 12 30Radical polymerization initiatorAzobisisobutyronitrile 1.2 3.6 5 0.6 1.2 3.6Benzoyl peroxide 3 15 0.6 4Cooking Solvent bButyl acetate 40 60 20 60Xylene 20 40Ethylene glycol monoethyl ether 20Polymerization Catalyst bAzobisisobutyronitrile 0.6 1.8 0.6 0.6 1.8Benzoyl peroxide 1.5 0.2Diluting SolventToluene 80 130Xylene 120 80 120Butyl acetate 100 100Methyl isobutyl ketone 30Butanol 10Methyl ethyl ketone 35Reaction Temperature (°C.) 100 115 130 110 120 140 80 105 110 120Appearance of Polymer Solution clear clear clear translucent clear clear clear turbid clear turbidViscosity of Polymer Solution U H A P K A.sub.3 Z W K FMolecular Weight of Polymer (× 10.sup.3) 89 54 9 43 27 1 150 72 65 32__________________________________________________________________________ Note (*1): ##STR3##
EXAMPLES 1 TO 43
Forty-three samples of antifouling coating were prepared by dispersing the copolymer solutions I to VII with a homomixer (2,000 rpm) in accordance with the formulations shown in Tables 2 and 3 (the figures in the tables are percents by weight). Paraffin wax 120P, paraffin wax 155P, microcrystalline wax 170M, and petrolatum Nos. 1 and 4 listed in Tables 2 and 3 are petroleum waxes of the types specified in JIS K 2235; ISO VG 10 and ISO VG 100 are liquid paraffins of the types specified in JIS K 2231; KF 96 L-10 and KF 96 H-50,000 are the trade names of Shin-Etsu Chemical Co., Ltd. for silicone oils; Oil Blue®2N is the trade name of Orient Chemical Industry Co., Ltd. for a dye; and Disparon ®6900-20X and Aerosil®300 are the trade names of Kusumoto Kasei K.K. and Nippon Aerosil Co., Ltd, respectively, for antisagging agents.
COMPARATIVE EXAMPLES 1 TO 15
Fifteen samples of antifouling coating having the formulations shown in Table 4 were prepared as in Examples 1 to 43 except that copolymer solutions III, V, VII to X and KE 45 TS (the trade name of Shin-Etsu Chemical Co., Ltd. for a 50 wt% toluene solution of a low temperature curing oligomer-like silicone rubber) or an organotin copolymer solution (Comparative Example 11) were employed.
The organotin copolymer solution used in Comparative Example 11 had been prepared by copolymerizing 40 parts of methyl methacrylate, 20 parts of octyl acrylate and 40 parts of tributyltin methacrylate; the copolymer had a weight average molecular weight of 90,000 and was dissolved in xylene to form a clear 50 wt% solution. The silicone oil designated as KF 96 H-60,000 in Table 4 was a product of Shinetsu Chemical Industry Co., Ltd. This silicone oil (kinetic viscosity: 60,000 cSt at 25° C.), caproic acid (carbon number: 6), camellia oil (m.p.: -17° C.) and methyl caproate (carbon number: 6) were not within the category of the slipping agents that are specified by the present invention for incorporation in the claimed antifouling coating.
TABLE 2 Example 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 Copolymer Solution (I) 45 90 56 64 Copolymer Solution (II) 50 50 60 56 Copolymer Solution (III) 60 60 60 60 60 60 72 Copolymer Solution (IV) 50 Copolymer Solution (V)55 Copolymer Solution (VI) 80 Copolymer Solution (VII) 40 63 38 Organic Amine Dodecylamine 1 Tetradecylamine5 3 Hexadecylamine 3 2 Octadecylamine 10 Dihydrogenated tallow- alkylmethylamine 10 Tetradecyldimethy lamine 10 Tallow alkylamine 27 3 Soybean alkylamine 35 5 Petroleum Wax Petrolatum No. 1 5 3 10 Liquid Paraffin ISO VG 10 5 7 Silicone Oil KF 96 L-10 (kinetic viscosity: 10 cSt at 25° C.) 4 3 2 4 Fatty Acid Ester Tallow (m.p.: 45° C.) 5 Palm oil (m.p.: 41° C.) 5 Pigment 2 TiO.sub.2 5 2 Dye Oil Blue 2N 1 Antisagging Agent Disparon ® 6900-20X 3 2 2 3 2 6 8 5 6 3 5 5 3 3 Aerosil ® 300 1 2 1 1 1 2 Diluting Solvent Toluene 30 19 13 28 20 40 48 8 5 4 5 23 6 Xylene 22 20 10 20 3 8 15 22 5 10 10 27 4 15 10 Ethyl acetate 30 20 10 18 10 10 15 9 2 10 5 5 Methyl isobutyl ketone 2 5 4 Isopropyl alcohol5 9 5 6 2 Total 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
TABLE 3 Example 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 Copolymer Solution (I) 64 56 72 72 56 Copolymer Solution (II) 40 65 54 56 Copolymer Solution (III) 42 54 48 54 54 Copolymer Solution (IV) 64 Copolymer Solution (V) 56 40 64 Copolymer Solution (VI) 56 Copolymer Solution (VII) 60 72 56 Petroleum Wax Paraffin wax 120P 9 7 Paraffin wax 155P 20 Microcryst alline wax 170M 3 Petrolatum No. 1 8 3 Petrolatum No. 4 20 Liquid Paraffin ISO VG 10 7 ISO VG 100 14 Silicone Oil KF 96 L-10 (kinetic viscosity: 10 cSt at 25° C. 4 KF 96 H-50000 (kinetic viscosity: 5 × 10.sup.4 cSt at 25° C.) 6 Fatty Acid Stearic acid (m.p.: 70° C.) 7 Caprylic acid (m.p.: 17° C.) 4 Fatty Acid Ester Tallow (m.p.: 45° C.) 12 Lard (m.p.: 37° C.) 9 12 Japan tallow (m.p.: 53° C.) 20 Palm oil (m.p.: 41° C.) 8 Spermaceti (m.p.: 48° C.) 12 Bees wax (m.p.: 63° C.) 3 Stearyl stearate (m.p.: 63° C.) 8 Tripalmitin (m.p.: 58° C.) 3 Pigment TiO.sub.2 5 Dye Oil Blue ®2N 3 Antisagging Agent Disparon ® 6900-20X 2 2 3 3 2 2 2 2 3 2 2 Aerosil ® 300 1 1 1 1 1 1 1 Diluting Solvent Toluene 27 10 23 6 5 20 16 33 10 22 20 7 Xylene 20 30 12 26 10 20 10 20 11 17 21 10 16 12 20 20 30 15 Ethyl acetate 10 20 5 5 5 10 20 7 10 10 20 10 10 5 Methyl isobutyl ketone 5 4 10 10 3 Isopropyl alcohol 2 3 3 Total 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100
TABLE 4__________________________________________________________________________ Comparative Example 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15__________________________________________________________________________Copolymer Solution (III) 42 42Copolymer Solution (V) 42Copolymer Solution (VII) 42Copolymer Solution (VIII) 50 56Copolymer Solution (IX) 50 60Copolymer Solution (X) 50 42Silicone RubberKE 45 TS 50 50 50 50Solution of Organotin Copolymer 40Petroleum WaxPetrolatum No. 1 10Petrolatum No. 4 12Liquid ParaffinISO VG 10 10Silicone OilKF 96 L-10 (kinetic viscosity:10 cSt at 25° C.) 10KF 96 H-60000 (kinetic viscosity:6 × 10.sup.4 cSt at 25° C.) 9Fatty AcidCaproic acid 9Fatty Acid EsterPalm oil (m.p.: 41° C.) 20Camellia oil (m.p.: -17° C.) 9Tripalmitin (m.p.: 58° C.) 9Methyl caproatePigmentTiO.sub.2 5Cuprous oxide 40Antisagging AgentDisparon ® 6900-20X 3 3 3 2 3 2 2 2 2Aerosil ® 300 1Diluting SolventToluene 47 47 47 9 50 40 40 40 20 20 20 20Xylene 21 18 20 12 22 15 22 22Ethyl acetate 10 20 5 5 5 5Methyl isobutyl ketone 5Isopropyl alcohol 2Total 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100__________________________________________________________________________
The performance of the samples of antifouling coating prepared in Examples 1 to 43 and Comparative Examples 1 to 15 was evaluated by a physical performance test, the measurement of slip angles for the surface of the film of coating formed from the individual samples and by an antifouling performance test. Each of the tests and measurement thereof was conducted by the procedures shown below. The results are shown in Tables 5 to 7.
Physical Performance Test
The storage stability, drying property and adhesion to a substrate were evaluated for each sample by the following methods.
(A) Storage Stability
200 ml of each sample was put into a glass container (capacity: 250 ml) which was closed with a cap. The container was stored in a humidified thermostatic chamber (70° C.×75% RH) for two weeks. The stability of the sample was determined in terms of any increase in its viscosity and evaluated by the following criteria: o, the increase in viscosity was less than 10% by the initial value; Δ, the increase was from 10% to less than 100% of the initial value; and x, the increase was at least 100% of the initial value.
(B) Drying Property
In accordance with the method specified in JIS K 5400.5.8, each of the samples was coated onto a glass plate for a wet film thickness of 100 μm with a film applicator and the drying property of the film was evaluated by the following criteria: o, the tack-free drying time was less than 1 hour; Δ, the tack-free drying time was from 1 hour to less than 3 hours; and x, the tack-free drying time was at least 3 hours. Each of the test pieces had been desiccated in a humidified thermostatic chamber (20° C.×75% RH).
(C) Adhesion to Substrate
Evaluation of adhesion to a substrate was conducted in accordance with the method of a cross cut adhesion test specified in JIS K 5400.6.15; each of the samples was coated onto a polished steel panel (150×70×1 mm) for a wet film thickness of 100 μm with a film applicator and dried for 1 week in a humidified thermostatic chamber (20° C.×75% RH); a 20 mm long crossed groove was cut through the film into the substrate with a cutter knife; the so prepared test piece was set in an Erichsen film tester and a steel ball was pressed against the center of the back side of the test piece to produce a vertical deformation of 10 mm. The adhesion of the film to the substrate was evaluated in terms of the length of peel from the substrate as measured from the center of the cross cut. The criteria used were as follows: o, 0 mm; Δ, less than 5 mm; and x, 5 mm or more.
Measurement of Slip Angle
Test plates were prepared in the same manner as in the case of the drying test (B) and the angle of slip on the surface of the film of coating formed on each test plate was measured with a slip angle meter. As shown in FIGS. 1(A) and (B), the slip angle meter was composed of a transparent glass plate 1, a fastening device 2, a support rod 3 and a movable plate 4. The movable plate 4 was disposed on the glass plate 1 in such a manner that it was fixed at one end A with the fastener 2 while the other end B was movable upwardly along the rod 3.
The procedures of slip angle measurement were as follows. First, as shown in FIG. 1(A), a test plate 5 was placed horizontally, with the film of coating facing up, on the movable plate 4, and a given amount (0.2 ml) of sterilized filtered seawater was injected with a syringe to deposit a waterdrop 6 at a position whose distance (γ) from the fastener 2 (i.e., one end A of the movable plate 4) was 185 mm. Then, as shown in FIG. 1(B), the other end B of the movable plate 4 was moved upwardly along the rod 3 at a speed of 1 mm/sec. The angle of inclination, α, of the movable plate 4 at which the waterdrop 6 began to slide down the inclined test plate 5 was measured and used as the slip angle of the surface of the film of coating on the test plate.
All measurements were conducted in a humidified thermostatic chamber (25° C.×75% RH) and three measurements with each test plate were averaged to calculate the slip angle for that plate.
Antifouling Performance Test
Sand blasted steel panels (100×200×1 mm) were coated with a coal tar-vinyl based anticorrosive paint. Both surfaces of each panel were sprayed with two layers of a coating so as to provide a dry film thickness of 120 μm on each side.
The so prepared test panels were immersed in seawater at Yura Bay, Sumoto, Hyogo, Japan for 36 months, during which period the increase in the area of the test panel that was covered by the growth of fouling marine organisms (% attachment of fouling organisms) was measured at regular intervals.
TABLE 5__________________________________________________________________________ Example 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21__________________________________________________________________________Storage stability o o o o o o o o o o o o o o o o o o o o oDrying property o o o o o o o o o o o o o o o o o o o o oAdhesion to substrate o o o o o o o o o o o o o o o o o o o o oSurface slip angle (degrees) 8.3 8.5 9.1 8.8 8.8 8.6 8.6 8.5 7.9 8.1 8.7 7.2 8.3 7.5 7.8 9.5 8.4 9.8 8.5 8.6 7.9Antifouling test3 mo. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 06 mo. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0% Attachment of foulingorganisms12 mo. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 018 mo. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 024 mo. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 030 mo. 5 1 3 3 1 2 3 1 0 0 0 0 0 0 0 0 0 0 0 0 036 mo. 10 5 10 10 5 10 10 5 0 0 0 0 0 0 0 0 0 0 0 0 042 mo. -- -- -- -- -- -- -- -- 0 0 0 0 0 0 0 0 0 0 0 3 748 mo. -- -- -- -- -- -- -- -- 0 0 0 0 0 0 0 0 0 0 0 10 20__________________________________________________________________________
TABLE 6__________________________________________________________________________ Example 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43__________________________________________________________________________Storage stability o o o o o o o o o o o o o o o o o o o o o oDrying property o o o o o o o o o o o o o o o o o o o o o oAdhesion to substrate o o o o o o o o o o o o o o o o o o o o o oSurface slip angle (degrees) 8.6 8.4 8.7 7.9 8.1 8.4 7.5 8.3 8.6 8.1 7.9 8.6 8.3 8.7 8.4 8.8 8.9 8.5 8.5 7.9 9.4 9.5Antifouling test3 mo. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 06 mo. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0% Attachment of foulingorganisms12 mo. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 018 mo. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 024 mo. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 030 mo. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 036 mo. 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 042 mo. -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --48 mo. -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --__________________________________________________________________________
TABLE 7__________________________________________________________________________ Comparative Example 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15__________________________________________________________________________Storage stability o o o o o o x x x x Δ o o o oDrying property Δ x x Δ x x Δ Δ x x o Δ Δ Δ ΔAdhesion to substrate o o o o o o x x x x o o Δ o oSurface slip angle (degrees) 13.0 12.3 11.2 12.1 12.6 11.8 15.0 13.1 14.0 13.2 25.0 10.5 11.2 10.9 10.6Antifouling test3 mo. 0 0 0 0 0 0 5 0 0 0 0 0 0 0 06 mo. 2 1 3 2 1 3 40 3 1 1 0 0 0 0 0% Attachment of foulingorganisms12 mo. 5 2 10 5 2 10 60 15 5 2 0 0 0 0 018 mo. 20 15 35 20 15 35 100 80 40 40 5 0 3 1 524 mo. 50 40 70 50 40 70 100 95 70 60 20 2 10 5 1030 mo. 70 60 90 70 60 90 100 100 85 65 30 10 15 10 2036 mo. 80 65 100 80 65 100 100 100 100 80 45 40 40 30 3542 mo. -- -- -- -- -- -- -- -- -- -- -- -- -- -- --48 mo. -- -- -- -- -- -- -- -- -- -- -- -- -- -- --__________________________________________________________________________
As the data in Tables 5 to 7 show, the samples of antifouling coating prepared in Examples 1 to 43 were satisfactory in storage stability, drying property and adhesion to substrate. The films of coating formed from these samples had surface slip angles within the range of 7 to 10 degrees. The films of coating from the samples of Examples 1 to 8 which did not use any slipping agent also had surface slip angles within the range of 7 to 10 degrees. This shows the fact that the polymer specified by the present invention was sufficient to form a film of coating that had a satisfactory degree of surface lubricity. No attachment of fouling organisms was observed for a period of at least 24 months of immersion in seawater. In the tests conducted with the samples prepared in Examples 8, 20 and 21, slight attachment of fouling organisms was observed after 30 months, but their antifouling effects were satisfactory.
The samples prepared in Comparative Examples 1 to 6 used polymer solutions that were outside the scope of the present invention; they were unsatisfactory with respect to drying and antifouling properties and the films of coating formed therefrom had undesirably high surface slip angles.
The samples prepared in Comparative Examples 7 to 10 were silicone rubber based paints and were unsatisfactory with respect to storage stability, drying property and adhesion to substrates. They were also low in antifouling effects as manifested by the high slip angles of the films of coating formed from these paints.
The sample prepared in Comparative Example 11 was an antifouling paint based on an organotin copolymer. It was somewhat poor in storage stability and antifouling effects. The film of coating formed from this paint was rather hydrophilic and had a high surface slip angle.
The samples prepared in Comparative Examples 12 to 15 used compounds that were not within the definition of the slipping agent specified by the present invention. These samples proved to be inferior to the samples of Examples 1 to 43 in each of the performance tests conducted.
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof. | An antifouling coating is described, that contains as its essential components a polymer of one or more of the monomers A represented by formula (1) and/or a copolymer composed of one or more of the monomers A and one or more monomers B that are radical-copolymerizable with said monomer A: ##STR1## wherein X is a hydrogen atom or a methyl group; n is an integer of 2 to 4; and m signifies the average degree of polymerization and ranges from 0 to 70. | 2 |
TECHNICAL FIELD
[0001] Embodiments in accordance with the invention are related to frequency references, and more particularly, to distributing frequency reference information among devices in a test or production environment, such as among test instruments, or between test instruments and a device under test.
BACKGROUND
[0002] Many laboratory and manufacturing test environments use a variety of electronic test and measurement equipment, including for example, signal generation and measurement instruments. In any situation where multiple instruments are used, the question of accuracy arises. If a signal generator is programmed to generate a signal at 146.115 MHz, and a frequency counter measures that frequency at 146115003.7 Hz, which instrument is more accurate? When the frequency counter reports 146115006.2 Hz a few hours later, which instrument has changed?
[0003] Signal generation and measurement instruments generate and measure signals with respect to an internal oscillator, a reference, commonly a signal source of 10 MHz. With multiple instruments each having their own internal oscillator or timebase, instantaneous differences in frequency, as well as drifting differences over time are inevitable.
[0004] One approach to solving this problem is to use more stable oscillators in equipment. Companies such as Agilent Technologies offer precision timebases as an option on many products. These timebases, typically a double-oven temperature controlled crystal oscillator, greatly increase the accuracy and stability of an instrument, as well as increasing the instrument's price, weight, heat generation, and power consumption; for best performance, these timebases must be powered continuously. And with a suite of instruments each with its own precision oscillator, issues of differences between instruments have been pushed over a few decimal places, but are still present.
[0005] Another approach to the problem is to drive instruments from a common oscillator. This approach makes the fundamental assumption that all instruments are able to use the same reference frequency. This common reference frequency may be generated by one instrument, as an example, a master instrument with an upgraded timebase oscillator, or an external reference such as a GPS-synchronized reference oscillator, a rubidium standard, or other “house” standard. The reference signal must be distributed to each instrument. This means each instrument requires yet another signal connector (typically a rear-panel BNC), which adds cost and takes up space. Yet another cable must be run from each instrument to a distribution point, further adding to the rat's nest of cables. To maintain spectral purity and low phase noise, special distribution amplifiers must be used. Additional cabling between instruments can introduce ground loops and other undesirable signals which can make complex test and measurement environments even more complex.
[0006] Instruments in a test environment are often required to use reference signals from a device under test (DUT) such as a cellular base station (BTS). When an instrument is required to “lock on” to such a nonstandard reference using reference signals, that instrument can then serve as a master for other instruments in the test suite.
SUMMARY OF THE INVENTION
[0007] An oscillator is synchronized to an external reference through the use of timing synchronization information provided over a computer network. Precision time references distributed across a computer network, such as provided by the IEEE 1588-2002 standard, provide precise time and interval data. In one embodiment, precision interval information is used to adjust the frequency of an oscillator. In another embodiment, precision interval information is used to determine the error of an oscillator in an instrument; the determined error is used to correct instrument operation. In a third embodiment, an arbitrary frequency reference is distributed over a network by converting frequency information to interval information and distributing the interval information over the network. The interval information may deliberately overstate its precision. Other instruments using this distributed interval information to adjust their local reference clocks will reproduce the arbitrary reference, including frequency drifts and other errors in the arbitrary reference.
BRIEF DESCRIPTION OF THE INVENTION
[0008] FIG. 1 shows a first block diagram of a network aware oscillator,
[0009] FIG. 2 shows a flowchart of frequency correction,
[0010] FIG. 3 shows a second embodiment of an instrument, and
[0011] FIG. 4 shows an instrument with an external reference.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0012] Many frequency generating and measuring instruments make use of a reference oscillator. In many applications, such as in complex laboratory or test environments, it is desirable to synchronize many instruments to a common standard.
[0013] Computer networks, particularly Ethernet networks, have become ubiquitous, even in the test and measurement environment.
[0014] The IEEE-1588(TM)-2002 standard, hereinafter 1588 and incorporated by reference, provides a precision clock synchronization protocol for networked measurement and control systems. By implementing the standard, in particular by implementing the standard as it applies to Ethernet networks, clocks in multiple instruments on a network may be synchronized to a time source, known in 1588 terminology as a boundary, master, or grandmaster clock. Synchronization is obtained through the use of the Precision Time Protocol (PTP) defined by 1588. Packets defined by the standard are exchanged between instruments to achieve time synchronization. While the present invention describes implementations in terms of Ethernet networks, it should be noted that IEEE-1588 supports any network protocol with multicast messaging.
[0015] FIG. 1 shows a block diagram of a network aware oscillator according to a first embodiment of the present invention. Network aware oscillator 100 connects 410 to network 400 through 1588-enabled network hub 420 . Hub 420 may be any 1588-compliant hub, switch, or router; suitable switches and routers are available from companies such as Hirschmann Electronics and OnTime Networks. In the example shown, boundary clock 430 provides time synchronization services 440 according to the 1588 standard. OnTime Networks also produces 1588 boundary clocks, including GPS time synchronization.
[0016] Within network aware oscillator 100 , network interface 110 provides network services 120 to clients within the instrument. Network interface 110 also provides, in coordination with 1588 messages, precision timing signal 130 . For the present embodiment, precision timing signal 130 is in the nature of pulses at a predetermined interval, such as one pulse per second, or one pulse every two seconds. One such client is correction processor 300 . It should be noted that part of the 1588 standard includes additional timing signals as part of network services 120 , allowing synchronization without the delays and variations introduced by protocol stacks and operating system interactions.
[0017] The 1588 standard is a time synchronization standard. Using the Precision Time Protocol defined by the 1588 standard, processor 310 in correction processor 300 maintains the synchronization of its clock 320 with similar clocks in instruments attached to hub 420 . In the embodiment shown, the time is set by clock 430 . Timing parameters are stored in memory 330 .
[0018] Also present in instrument 100 is oscillator 200 . Oscillator 200 produces output signal 210 which is used by the instrument. In one example, this is a 10 MHz signal. Output signal 210 is also passed to correction processor 300 , and within the correction processor, to counter 150 and processor 310 . Control lines 350 allow processor 310 to reset, enable, and read the contents of counter 340 . Counter 340 is typically 32 bits wide or wider, so that processor 310 may count long periods of oscillator 200 . A 48-bit wide counter 340 allows for counting periods of many days at 10 MHz. Prescaling may also be used ahead of counter 340 .
[0019] In the network aware oscillator of FIG. 1 , a voltage-controlled oscillator is used for oscillator 200 . Such an oscillator has an input which allows its operating frequency to be adjusted. As an example, the Agilent 10811 and 10544 series crystal oscillators are oven-stabilized devices which provide a 10 MHz output. The electronic frequency control (EFC) input on these devices allows an output frequency adjustment of 1 Hz over a ±5V control range. Alternate embodiments of oscillator 200 may use any suitable oscillator topology, although crystal oscillators are preferred. Placing a variable capacitance (varactor) diode in the oscillator feedback loop allows for electronic frequency control (EFC) and the ability to change the oscillator frequency, even of a crystal oscillator, slightly. An analog EFC input is typically fed by a digital to analog converter. Other electrically tunable oscillators may also be used, such as dielectric resonant oscillators (DRO) or ytterbium-iron-garnet tuned oscillators (YTO) common in very high frequency systems.
[0020] In operation according to the present invention, processor 310 responding to PTP requests through network 400 establishes precision time intervals according to an external reference. By counting 340 suitable periods of oscillator 200 output 210 , processor 310 develops an error indication 360 and used this error indication to adjust electronic frequency control 220 of oscillator 200 to trim its operating frequency and phase.
[0021] According to the 1588 specification, all systems on a network containing clocks may participate in selecting a master clock. This selection is performed using the 1588 PTP protocols and allows systems receiving PTP Sync messages to select the best master clock, and is described in section 6.1.2 Operation Overview of the 1588 Specification. When a master clock is identified, it sends out periodic Sync messages which allow other systems, known in 1588 as slave clocks, to synchronize their clocks to the master clock. This synchronization process is described in section 7.8 of the 1588 Specification
[0022] The application and adaptation of this process to the present invention is shown in the flowchart of FIG. 2 Referring also to FIG. 1 , in this embodiment correction processor 300 synchronizes its local clock 320 with a master clock,boundary clock 430 in the embodiment shown. This synchronization is maintained through periodic PTP messages passed 120 through network interface 110 .
[0023] According to the present invention, correction processor 300 selects a measurement interval for counting pulses from oscillator 200 . As an example, assume an interval of 100 seconds is used.
[0024] Using 1588 timing information provided 120 by network interface 110 , pulses from oscillator 200 are counted for the selected measurement interval.
[0025] Next, the reference correction is calculated. Assume for example that the measurement interval is 100 seconds with an uncertainty of 200 nanoseconds (ns). For this interval, the expected number of pulses from oscillator 200 would be the frequency times the interval plus or minus the number of counts in the uncertainty. For the example given, with an interval of 100 seconds and a reference oscillator frequency of 10 MHz, the expected number of counts would be in the range 100 times 10 million, plus or minus 2 counts. If the actual number of pulses counted during the measurement interval is higher than the calculated range, oscillator 200 is running fast. If the actual number of pulses counted during the measurement interval is lower than the calculated range, oscillator 200 is running slow. This error indication is generated as signal 360 .
[0026] If a correction is needed, it may be calculated using any number of models. The system represented by oscillator 200 with electronic frequency control 220 and correction processor 300 forms a control loop, and standard analytical tools may be employed for example to insure a suitably damped response. The correction based on error indication 360 is calculated and passed to electronic frequency control input 220 of oscillator 200 , altering its operating frequency.
[0027] As shown in the flowchart of FIG. 2 , the process continues, both in terms of maintaining clock synchronization, and of correcting oscillator 200 . The longer the measurement interval, the closer the synchronization between oscillator 200 and the master clock, at a cost of slower response to change. In the example shown, using measurement intervals of 100 seconds and measurement uncertainties on the order of 200 nanoseconds, synchronization on the order of one part in ten to the eighth may be achieved. It should be noted that this high degree of synchronization is achieved without needing any knowledge of the operating frequencies of the clocks or oscillators involved.
[0028] In correcting the frequency of oscillator 200 , the first-order correction is of operating frequency and phase. Correction information is stored in memory 330 . By collecting measurement and correction information over longer periods of time, hours to days, second order effects such as aging in a temperature-stabilized crystal oscillator may be modeled and corrected.
[0029] In implementing the present invention, network interface 110 and correction processor 300 comprising processor 310 , clock 320 , memory 330 , and counter 340 may be a portion of network aware oscillator 100 , or they may be part of a larger instrument in which the reference is embedded. Network aware oscillator 100 could be offered as a stand-alone device, or as an option in instruments.
[0030] In a second embodiment of the invention as shown in Fig, 3 , precision interval information is delivered 130 to correction processor 300 . Correction processor 300 counts periods of oscillator 200 as defined by precision interval signal 130 . Where the first embodiment of the invention developed correction information used to directly adjust the frequency of the oscillator, in this embodiment correction information 360 is produced and propagated to the instrument to correct for errors in the frequency of oscillator 200 .
[0031] In the case of a frequency measuring instrument such as a counter, correction data 520 may be used digitally to correct measurements. As an example, assume a frequency counter with a nominal timebase of 10 Mhz measures 154904876 cycles in a one second interval, the interval defined as 10,000,000 cycles of the timebase oscillator. If correction data 520 indicates the 10 Mhz oscillator is 8 cycles per second slow, operating at 9999992 Hz rather than 10 Mhz, the measured data may be corrected and reported or displayed as 154905000 Hz rather than 154904876 Hz. In the case of a signal generating instrument such as a frequency synthesizer, device operation may be adjusted to take into account correction data 520 .
[0032] In a third embodiment of the invention as shown in FIG. 4 , an arbitrary frequency reference is distributed via a network to one or more instruments and used to correct references in those instruments. Arbitrary frequency reference 430 generates interval information 440 which is processed by IEEE-1588 aware network interface 420 and made available over network 410 . The IEEE 1588 standard allows for devices to select a master based on accuracy information published in network messages for each source. For arbitrary source 430 to insure it is used as the master in a network, it may be desirable to deliberately overstate the published accuracy of reference 430 .
[0033] Instruments 700 , 710 , and 720 connect to network 410 . These instruments operate in accordance with the embodiments of the invention as shown in FIGS. 1 through 3 to match their reference oscillators to the performance of arbitrary reference 430 . Thus, frequency errors, frequency drift, and the like in reference 430 will be tracked in the operation of instruments 700 , 710 , and 720 .
[0034] While the embodiments of the present invention have been illustrated in detail, it should be apparent that modifications and adaptations to these embodiments may occur to one skilled in the art without departing from the scope of the present invention as set forth in the following claims. | Network aware oscillator synchronization via a computer network. A correction processor connected to an oscillator uses precision timing signals propagated over a digital network to generate an error signal. IEEE-1588 time synchronization protocols produce precision time signals which are converted to precision interval signals. In one embodiment a correction processor uses the precision interval signals to count pulses of the oscillator. A correction circuit compares the counter output with a predetermined value and generates an error signal. The error signal may be used to correct the oscillator, as in a voltage controlled oscillator. Or, the error signal may be propagated to consumers of the oscillator. This error signal, for example, may be used to correct an instrument display. An arbitrary reference oscillator may be used to generate the precision timing signals propagated on the network, slaving other oscillators to it. The precision of the reference oscillator may be deliberately overstated to insure it is used as a master. | 7 |
RELATED APPLICATIONS
[0001] This application is a continuation-in-part of my application Ser. No. 13/430,194, filed Mar. 26, 2012, and Applicant claims priority in part pursuant to 35 USC §120. Application Ser. No. 13/430,194 is based upon provisional applications 61/468,628 filed Mar. 29, 2011 and 61/475,302 filed Apr. 14, 2011, and claims priority therefore under 35 U.S.C. §119(e). These applications are incorporated by reference herein.
FIELD OF THE INVENTION
[0002] The present invention relates to transparent cake covers with removable candle decks which do not pierce the cake being decorated by candles.
BACKGROUND OF THE INVENTION
[0003] The age-old problem with birthdays and other occasions involving cakes with candles atop is one of sanitation relating to the task of blowing out the candles. When the celebrant blows out the candles, the liquid wash which emanates from his or her mouth descends upon the cake possibly infecting it with a deluge of germs, fluids, and perhaps other debris. The tradition of substituting multiple cupcakes for the cake at such celebrations is becoming more popular. They substituting multiple cupcakes for the cake at such celebrations is becoming more popular. They are often grouped in a cluster with one candle on each cupcake wherein the celebrant proceeds to blow out the candles with similar unsanitary exposure.
[0004] This sanitary problem with candle-blowing atop cakes has been explored by several patents in the prior art. Carlson, with his birthday cake cover with base, of U.S. Pat. No. 2,758,458, deals with the problem by providing a circular cake cover with slightly domed top surface having a pattern of recesses for candles and a central knob. The cover is securely latched onto the base.
[0005] The birthday cake cover and candle holder of Barfus (U.S. Pat. No. 4,721,455) is supported by a stake into the cake and covers the top surface only, thereby offering little protection to the side of the cake. The cake protector of MacKendrick (U.S. Pat. No. 3,819,455) includes a central dome shaped section with integral candle holders and a lower flange which rests on the top surface of the cake. The sides of the cake are protected by a collar with inwardly directed upper flange and an outwardly directed lower flange. In operation, the collar is lowered onto the central dome wherein the upper flange rests on the lower flange of the dome section, while the lower collar flange rests on, or is close to, the supporting surface.
[0006] The cake cover of Mc Birnie (U.S. Pat. No. 3,736,214) includes several parts. Four stakes with flat tops are forced into the top surface of the cake. They support a rigid transparent disk slightly larger than the cake diameter. A transparent flexible sheet is then draped over the disk; a second transparent disk of similar size is then placed atop the sheet. Separate candles in holders with flat bottoms are then placed atop the top disk. If the sheet is a woven fabric, the protection of the side of the cake is in some jeopardy. The fragility of separate candles in holders is a safety concern.
[0007] Wexler's cake cover and candle holder (U.S. Pat. No. 4,938,688) uses a thin vacuum formed transparent plastic cover with sloping sides and flat top with integral candle indentations to cover a cake. Wexler's protective cake cover and candle holder (U.S. Pat. No. 4,884,966) also is based on the use of a vacuum formed plastic cover, but it now also uses tubular standoffs on the cake icing separating the top cover surface from the cake top. Besides having candle indentations, the top surface also can use these indentations as cutting guides by marking the top of the cake.
[0008] The prior art does not reveal a protective transparent cover for a cup cake with a candle holder atop. Also, the prior art does not reveal a transparent cake cover with a removable candle deck to permit dual-use as a fruit, cheese, or other food container with an unobstructed view, while at the same time, avoiding piercing of any part of the cake when used with a cake and a candle deck.
OBJECTS OF THE INVENTION
[0009] It is therefore an object of the present invention to provide a sanitary cake cover with a removable candle deck, which protects the contents of the cake from contamination during blowing out of celebratory lighted candles.
[0010] It is also an object of the present invention to provide a transparent cake cover with a removable candle deck, which does not pierce the cake being decorated by celebratory lighted candles.
[0011] It is also an object of the present invention to provide a cake cover which has a removable candle deck, wherein the cake cover can be used without the candle deck.
[0012] Other objects which become apparent from the following description of the present invention.
SUMMARY OF THE INVENTION
[0013] In keeping with these objects and others which may become apparent, the present invention is a sanitary cake cover which is a dual-use container, which houses a cake of a geometric shape, such as round, rectangular or fanciful (i.e. football, shamrock, cartoon character or organizational logo) shape in a transparent housing impervious to assault by normal airborne contaminants, such as dust and dirt as well as that from contaminated, microbe infiltrated, expelled breath, during the act of blowing out candles.
[0014] A separate removable candle deck with through holes 3 or, non-through holes, for holding candles, which can be attached to or nestled securely atop the cover, is used to enable the container to be used for display and storage of other food items without the obstruction of candle recesses. The flat top of either a round, rectangular or other shaped cover has a peripheral top ridge forming a flat central recess of dimensions to fit the flat candle deck. The candle deck can be optionally stored underneath the flat base when not in use. In a further option, the flat base platter can have a recess on its underside, for storing the candle deck within the recess and which is held in place by a fastener.
[0015] In another embodiment, a transparent cover with a cylindrical side and a hemispherical domed top is used as a cupcake cover to cover a small, individually baked cupcake. The center of the dome has a hole accepting a bottom extension of a decorative ferrule with a candle recess in its center. This offers equivalent protection for a cupcake as the sanitary cake cover offers to a cake during a candle-blowing ceremony. In a preferred embodiment, the cupcake cover includes a candle deck interchangeable with a knob for the preferably domed shaped cupcake cover, where the candle deck, (which optionally can be stored below the platter) is nested in a recess at the top of the cupcake holder during candle lighting use. The domed cupcake cover can optionally be open at the bottom for resting over a cupcake placed on a tabletop, where the bottom peripheral edge of the cupcake cover rests on the table.
[0016] The cake cover embodiment is available with several variations. First, the transparent cylindrical, rectangular or other shaped cover can just be supported by a flat base. Alternatively, a round cylindrical cover can optionally have engagement members which mate with and lock into recesses on the base.
[0017] By the word, “cake,” covered by the cover and candle deck herein, it is assumed to be a monolithic, large cake of any configuration, a plurality of pre-sliced cake slices organized as a cake or as individual slices, or one or more cupcakes.
[0018] The base can optionally be enhanced with indicia which extend beyond the circumference of a cake, as a guide to cutting standard sized slices. The bottom of the base of the cake cover, either for a full sized cake or for an individual cupcake, can have a plurality of support legs (such as three) raising it off a support surface, such as a table, and providing space for storage of the candle deck when not in use. A central knob can be attached through a hole in the cover or by other fastener means by threaded extensions, or by a press fit, with or without the candle deck in use. This knob is also preferably used to attach the candle deck to the cover.
[0019] The candle deck can also be used unattached to the cake cover or cupcake cover, with or without a central knob. In this variation, the flat depressed surface within the peripheral edge ridge of the cover top need not have a central hole to receive a screw thread or other fastener, thus resulting in a more appealing unobstructed view for dual-use service as a food item container.
[0020] In a further embodiment, the candle deck can be a set of candle holders extending from a top or bottom surface of the candle deck, where void spaces are provided between the candle holders to reduce the weight and manufacturing cost of the candle deck, whether the candle deck is used on a large cake or a small individual cupcake.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] The present invention can best be understood in connection with the accompanying drawings. It is noted that the invention is not limited to the precise embodiments shown in drawings, in which:
[0022] FIG. 1 is an exploded perspective view of the first embodiment for the sanitary cake cover of this invention with a candle deck, attachment knob, cover, round birthday cake and plain base;
[0023] FIG. 2 is an exploded perspective view of the second embodiment for the sanitary cake cover of this invention for a rectangular cake, such as a “sheet cake”, showing the equivalent features as in FIG. 1 ;
[0024] FIG. 3 is an exploded perspective view of a third embodiment for a domed sanitary candle cover of this invention for a cup cake;
[0025] FIG. 4 is a perspective view of a fourth embodiment for a sanitary cover with an optional decorative starburst designed candle deck for a round cake; wherein the cover locks into the base;
[0026] FIG. 5 is an exploded perspective view of the sanitary cover of FIG. 4 more clearly showing the base indicia to guide slice cutting;
[0027] FIG. 6 is a perspective view of the sanitary cover of FIG. 4 housing fruit as in a dual-use configuration without a candle deck;
[0028] FIG. 7 is a close-up detail view in cross section of the top edge of the cover and the candle deck taken along view line “ 7 - 7 ” of FIG. 4 , when viewed in the direction of the arrows depicted therein;
[0029] FIG. 8 is a close-up detail perspective view of the respective lock members of the cover and the base as shown in the dashed circle line “ 8 ” of FIG. 4 ;
[0030] FIG. 9 is a perspective view of a knife guided by the indicia on the base being used to cut a slice of cheesecake;
[0031] FIG. 10 is a bottom perspective view of the base of the sanitary cover of FIG. 4 , showing three legs and the method of storing the candle deck flush against a bottom of the platter base;
[0032] FIG. 10A is an exploded bottom perspective view of the base of the sanitary cover of FIG. 4 , showing three legs and the method of storing the candle deck within a cut out counter sink recess in the bottom of the platter base;
[0033] FIG. 10B is a crossectional detail view of the embodiment shown in FIG. 10A , showing the candle deck stored within the recess of the platter base and held in place by a fastener.
[0034] FIG. 11 is a top perspective detail showing a different knob used to attach the candle deck of FIG. 4 , where knob has a threaded extension extending through the candle deck and through the top of the cover, where the threaded extension is engageable with a threaded fastener, such as a nut;
[0035] FIG. 11A is a top perspective detail showing a threaded stem knob engageable with an upwardly extending threaded boss, integrally formed with the top of the cover.
[0036] FIG. 12 is a perspective view of a child flanked by two healthcare providers blowing out candles on a cake enclosed in a cake cover of this invention, possibly in a hospital environment;
[0037] FIG. 13 is an exploded perspective view of a fifth embodiment for a cake cover wherein the candle deck is not attached to the cover but is nestled inside the top depressed area, wherein the peripheral edge ridge is deeper than the previous embodiments to accommodate the thickness of a fastener, such as an attachment nut;
[0038] FIG. 13A is a central side detail crossection of the cake cover of FIG. 13 , taken along view line “ 13 A- 13 A” of FIG. 13 , showing the candle deck separated from the cover top by the thickness of a nut;
[0039] FIG. 13B is an alternate embodiment for a central side detail crossection of the cake cover of FIG. 13 , showing the candle deck resting on the top of the cover, where the candle deck has a lower counter sink region to accommodate the thickness of a nut therein threadably engaging a threaded knob extension;
[0040] FIG. 14 is an exploded perspective view of a sixth embodiment for an alternate type of candle deck that is not attached to the cover, wherein it has recessed, optionally removable, side handles, instead of a central knob;
[0041] FIG. 14A is an exploded perspective view of a seventh embodiment for an alternate type of candle deck with void spaces surrounding candle holders, which may extend up or down from the surface of the candle deck, within the confines of a peripherally extending edge curtain;
[0042] FIG. 14B is a crossectional detail view of the embodiment shown in FIG. 14A , taken along dashed view circle “ 14 B” of FIG. 14A .
[0043] FIG. 14C is a crossectional detail view of the embodiment shown in FIG. 14A , taken along view line “ 14 C- 14 C” of FIG. 14A , showing candles with respective candle holders, such as for example, with through holes or non-through holes for insertion of candles therein, and a knob with an extension attached to a threaded nut to the top of the cake cover;
[0044] FIG. 15 is a perspective view of a group of children, each with a respective cupcake with groups of candles, in an embodiment for a deck placed over a cupcake cover;
[0045] FIG. 16 is an enlarged perspective view of the preferred embodiment for a cupcake cover of FIG. 15 , with a candle deck held within a recess on top of the cupcake cover, where the candle deck is removable and storable under a base platter for the cupcake and cupcake cover;
[0046] FIG. 17 is an exploded perspective view of the cupcake cover embodiment of FIG. 16 ;
[0047] FIG. 18 is an exploded perspective view of the cupcake cover embodiment of FIG. 17 , but showing the ability to stow the deck under the base platter, and to use the embodiment to keep a cupcake item fresh;
[0048] FIG. 19 is a perspective view of a ninth alternate cupcake cover embodiment, wherein there is no platter, and the knob and ferrule are friction-fitted into the cover aperture;
[0049] FIG. 20 is a close-up detail perspective view of a tenth alternate embodiment for a cupcake cover with a knob with a threaded extension engaging a nut below the domed cupcake cover; and,
[0050] FIG. 21 is a perspective view of a cupcake cover similar to that of FIG. 19 , but showing the cover having a molded collar for frictionally receiving the knob or ferrule, eliminating the aperture.
DETAILED DESCRIPTION OF THE INVENTION
[0051] FIGS. 1 and 2 each show a transparent sanitary cake cover assembly (designated by reference numerals 1 or 15 ) of this invention with a removable candle deck for a round cake and for a rectangular cake respectively.
[0052] In FIG. 1 , cover 2 is a round transparent cover with top edge peripheral ridge 6 a and flat depressed region 6 . Cover 2 has optional lift handles 10 and a fastener means, such as a central hole 7 to accept the screw extension 5 b below flange 5 a of knob 5 , which fits through central hole 7 in removable candle deck 3 and attaches deck 3 to cover 2 via a fastener, such as nut 8 on the underside of depressed region 6 . Round cake 14 is supported by plain base 4 , and candles 12 populate some of grid holes 9 in candle deck 3 . Grid holes 9 can be through holes extending all the way through candle deck 3 , or can be partial recess holes with closed bottoms, extending into, but not all the way through, candle deck 3 .
[0053] FIG. 2 shows transparent sanitary cake cover assembly 15 for rectangular cake 24 which is supported by plain base 20 . A rectangular cover 16 with optional handles 19 , central hole 7 , and depressed region 18 , which supports rectangular removable candle deck 17 therein, when candle deck 17 is surrounded by upwardly extending peripheral ridge 18 a of rectangular cover 16 .
[0054] While FIGS. 1 and 2 show round and rectangular shapes for the transparent cover and cake therein, it is understood that other shapes for the transparent sanitary cake cover and cake itself may be used, for example, including other geometric shapes (i.e. triangles or ovals, etc.), or fanciful shapes (i.e. football, shamrock, cartoon character or organizational logo).
[0055] FIG. 3 shows the alternate embodiment for sanitary cover 25 for cup cake 30 . It has a transparent cylindrical side 26 with dome top 27 . Hole 29 accepts ferrule 28 snugly which has a recess for candle 12 on top.
[0056] FIG. 4 shows several alternate embodiment variations for a sanitary cake cover assembly 35 , which differs from sanitary cover 1 , which include sanitary cover 36 . Cover 36 locks into base 38 via two engaged locks 39 . Handles 41 , which are optionally removable, can be used for lifting in lieu of knob 40 . Removable candle deck 37 with a starburst pattern, or other array pattern, of candle holes 9 is attached to the top recessed region of plate cover 36 by fasteners, such as knob 40 . While base 38 shows cake-supporting pedestal plate 38 a with concentric cake support rings 38 b, it is known that, optionally, base 38 can be flat with no pedestal and/or rings.
[0057] FIGS. 5-11 show more details of the sanitary cake cover assembly 35 .
[0058] In contrast to FIGS. 1 and 2 , where the fasteners for knob 5 has threaded stem 5 b extending below flange 5 a, through candle deck 3 and hole 7 of cover 2 , in the exploded view of FIG. 5 , a fastener, such as screw 47 , enters through the bottom of central hole 46 in recessed region 45 of cover 36 , with peripheral ridge 45 a, to attach candle deck 37 via the threaded hole in the bottom stem 40 b of knob 40 , above flange 40 a. Also shown in FIG. 5 , optional external protrusion 48 of transparent cover 36 enters recess 49 on base 38 , to lock transparent cake cover 36 to platform base 38 . Optional indicia 51 are guides for cutting uniform cake slices.
[0059] FIG. 6 shows transparent sanitary cover 36 to house fruit 53 . It is noted that knob 40 used without candle deck 37 , which has been removed.
[0060] FIG. 7 shows crossection the detail at the edge of the top peripheral ridge 45 a of cover 36 , with candle deck 37 .
[0061] FIG. 8 shows a detail view of the engagement of lock housing 49 on base 38 and protrusion 48 extending from cover 36 , by rotating cover 36 relative to base 38 , so that protrusion 48 of sanitary cover 36 rests within the confines of lock housing 49 , such as, for example, below a ledge of lock housing 49 .
[0062] FIG. 9 illustrates cutting uniform slices of cheesecake 56 by aligning knife 57 with indicia marks 51 which extend beyond the circumference of cake 56 .
[0063] FIG. 10 shows the underside of platform base 38 with short legs 61 and a fastener, such as central screw stud 60 , which secures candle deck 37 for storage of candle deck 37 under base 38 , via a further complementary fastener, such as nut 8 .
[0064] FIG. 10A shows a platter base 238 for the sanitary cover 36 of FIG. 4 , showing a plurality of legs 261 and the method of storing the candle deck within a counter sink cutout recess 239 in the bottom of the platter base 238 , whereby the recess 239 has a diameter closely equivalent to the diameter of the candle deck 37 for insertion therein, whereby the candle deck 37 is held in place by nut 268 engageable with threaded fastener extension 260 centrally located within recess 239 . Holes 9 can be through holes extending all the way through candle deck 37 , or can be partial holes with closed bottoms.
[0065] FIG. 10B shows the embodiment shown in FIG. 10A , wherein candle deck 37 is provided with candle holes 9 and central hole 7 having threaded extension 260 engageable with fastener nut 268 , to hold candle deck 37 within recess 239 .
[0066] It is further noted that while FIGS. 1 and 2 do not require storing the candle deck below the respective platters 4 and 20 , it is assumed that platters 4 and 20 could be modified as shown in FIG. 10 to also store candle decks 3 and 17 thereunder, either flush with platters 4 and 20 , similar to platter 38 of FIG. 10 or with an indented recess 239 , as shown in platter 238 of FIGS. 10A and 10B .
[0067] FIG. 11 is a detail view of transparent sanitary cover assembly 35 having transparent cover 36 with peripheral upper ridge 34 a, and depressed recess 34 , using knob 5 to secure removable candle deck 37 via nut 8 .
[0068] FIG. 11A shows an alternate embodiment where knob 105 has a finial or other grasping portion 105 , having a stem 106 , supporting a circumferential flange collar 107 above a threaded member 108 , which engages a threaded upwardly extending boss 110 formed integrally with the top 136 a of cover 136 . Cover 136 has depressed recess 137 formed between the confines of upwardly extending peripheral edge rim 137 a extending along a top peripheral edge of cover 136 .
[0069] While FIG. 11A shows exterior threads on threaded stem 108 insertable within the internally threaded boss 110 , it is also known that the opposite configuration can be used, where a stem on knob 105 has interior threads and the boss has exterior threads engageable therewith (not shown).
[0070] FIG. 12 illustrates a possible vignette for a sanitary cake cover assembly 35 with three human figures and a transparent sanitary cover protected cake with several lighted candles 63 on candle deck 37 . The child 65 may have a transmitted disease, since he or she is flanked by two healthcare providers 66 wearing face masks. Child 65 can still safely blow out the candles. After the candle deck 37 is removed via knob 105 of FIG. 11A or by handles 83 of FIG. 14 , and the surface of transparent sanitary cover 36 is thoroughly disinfected, transparent sanitary cover 36 can be opened, revealing a protected cake.
[0071] Sanitary cover assembly 70 , as shown in FIG. 13 , shows an alternate embodiment for one variation with removable candle deck 3 unattached to transparent cover 71 , where candle deck 3 nestles on top of depressed region 73 within a high edge ridge 73 a. Note height of edge ridge 73 a is “Y” as indicated.
[0072] FIG. 13A is a central side cross section detail through knob 72 , showing removable candle deck 3 , and recessed region 73 a. It shows that knob 72 has a short threaded extension that is as long as nut 8 is thick, which is just slightly less than gap “X” as indicated. The total height of deck thickness plus gap “X” is equal to “Y”, the height of ridge 73 a. Note that recessed region 73 does not have a central hole. The draft angle of the edge ridge around deck 3 is an interference fit which keeps candle deck 3 level within gap “X”. Therefore, candle deck 3 is not connected by a fastener to transparent cake cover 71 , and is held in place by gravity within the recess 73 , formed by the upwardly extending peripheral top ridge 73 a of cover 71 .
[0073] FIG. 13B shows an alternate embodiment detail in crossection through knob 172 , showing removable candle deck 183 with candle holes 9 , and cover 71 having recessed region 73 and raised peripheral ridge 73 a of FIG. 13 . Knob 172 has a short threaded extension that is engageable with a nut 8 , but where candle deck 183 has a countersink region 183 a to accommodate nut 8 , so that nut 8 does not extend below the bottom of candle deck 183 , which sits in recess 73 upon the top of cover 71 , which therefore has no holes in it, and is smooth all along its top surface edge between the confines of ridge 73 a.
[0074] FIG. 14 shows a different variation of sanitary cover 80 assembly, also with an unattached removal candle deck 82 , which has recessed handles 83 at the edge for lifting, and no central knob is used. Here again, recessed region 84 (which can have a recessed ridge 84 a of less height than in FIG. 13 ) does not have a central hole. Candle deck 82 just rests atop recessed region 84 at the top of cover 81 when in use. The recess 84 diameter and ridge height are less critical in this variation. Handles 10 for carrying cover 81 are shown. Handles 10 can be permanently attached or molded to the side of cover 81 , or cover handles 10 can be optionally removable when cover 81 is stored and not used.
[0075] FIG. 14A shows respective candle deck 237 that rests within upper recess 45 with peripheral edge 45 a, but where candle holders 249 extend upward or downward from a surface of candle deck 237 , within a void area 247 , located within the confines of peripherally extending edge curtain 248 of candle deck 237 .
[0076] FIG. 14B shows a version of candle deck 237 having preferably cylindrical hollow candle holders 249 extending downward from a top 237 a of candle deck 237 , having peripherally extending edge curtain 248 , defining a void area 247 , into which candle holders 249 each extend into. Candle holders 249 can have through holes or partial, closed bottom holes.
[0077] FIG. 14C shows candles 12 being held in place for lighting within respective candle holders 249 extending from top 237 of candle deck 237 , whereby knob 240 has an extension 241 extending into central hole 207 and engageable with threaded fastener 278 , to temporarily hold candle deck 237 with recess 45 of cover 36 .
[0078] FIGS. 15 , 16 , 17 and 18 show three children at a birthday or other party, where each child 65 , 65 a, 65 b has their own respective domed or otherwise shaped cupcake cover 326 , covering respective cupcakes 330 , wherein further a candle deck 337 holds candles 12 within optionally beveled candle holders 349 extending up or down from candle deck 337 , which may optionally have through candle holes or non-through holes extending from deck 337 through beveled candle holders 349 . Cupcake cover 326 further includes a top recess 345 to hold candle deck 337 therein. Knob 340 attaches candle deck 337 to the top recess 345 of cupcake cover 326 via extension 340 a. Platter base 338 supports cupcake cover 326 thereon. Knob 340 has threaded extension 340 a engageable with fastener 348 , such as a threaded nut.
[0079] Optionally, platter base can be flat, or else adorned with cupcake support pedestal plate 338 a. As a further option, the candle deck can be a flat plate with holes similar to rounded deck 3 of FIG. 1 .
[0080] FIG. 18 shows the ability to stow the deck 337 within recess 339 under the platter base 338 , and to use the embodiment to keep an item fresh.
[0081] Also, while FIG. 16 shows a base platter 338 for storage of the candle deck 337 therein, FIG. 19 shows another alternate embodiment for a cupcake holder 426 with single candle 12 , where there is no platter underneath the cupcake and the knob 440 and candle holding ferrule 428 are friction-fitted into the cover aperture 449 .
[0082] FIG. 20 shows a further alternate embodiment for a cupcake holder 526 with knob 540 with threaded extension 540 a extending within through hole 547 and engaging a fastener 548 , such as a nut, below dome cover 526 . It is assured that a ferrule, such as ferrule 428 of FIG. 19 would be used, with a similar threaded mechanical arrangement similar to that of knob 340 having threaded extension 340 a extending within through hole 547 , for attaching to fastener, such as threaded nut 548 .
[0083] FIG. 21 shows cupcake holder 626 , similar to cupcake holder 426 of FIG. 19 , but showing the cover 626 having an upstanding molded collar 645 a with recess 645 for frictionally receiving respective friction fit bases 641 and 629 of the knob 640 or ferrule 628 therein, thereby eliminating the need for central aperture 449 of FIG. 19 .
[0084] While the aforementioned shows preferred embodiments, it is noted that other embodiments may be contemplated, as noted in the appended claims.
[0085] For example, in the foregoing description, certain terms and visual depictions are used to illustrate the preferred embodiment. However, no unnecessary limitations are to be construed by the terms used or illustrations depicted, beyond what is shown in the prior art, since the terms and illustrations are exemplary only, and are not meant to limit the scope of the present invention.
[0086] It is further known that other modifications may be made to the present invention, without departing the scope of the invention, as noted in the appended Claims. | A sanitary cake cover with a removable candle deck, which protects the contents of the cake from contamination during blowing out of celebratory candles. The transparent cake cover includes a removable candle deck for at least one candle, which does not pierce the cake or cover being decorated by lighted celebratory candles. The cake cover can be used without the candle deck. The sanitary cake cover is impervious to assault by normal airborne contaminants, such as dust and dirt as well from contaminated expelled breath during the act of blowing out candles. The separate removable candle deck is removable to enable the container to be used for other food items without the obstruction of candle recesses. The flat top of the cover has a peripheral top ridge forming a flat central depression of dimensions to fit the flat candle deck. | 5 |
BACKGROUND OF THE INVENTION
Two stroke cycle engines have been used heretofore mostly in extreme sized applications, being either very small or very large engine applications. The small engine applications are represented by such applications as lawn mowers and motor bikes where the low cost of manufacture is of paramount importance and some inefficiency of operation can be tolerated. In these applications, the bottom of the piston is used as a scavenging blower. The very large marine engine applications have been for use in ore boats, ships, etc., where the large reciprocating mass of the piston and connecting rod that is moved about would cause the four stroke cycle engine operation to be inefficient compared to the two stroke. Also, when these large applications have a need for scavenging and supercharging, large, expensive blowers are required as well as other accessory equipment. Such expense is tolerated because of the large capital investment of the application.
In midsize engine applications, the two stroke cycle engine has not been used widely, except for two stroke diesel truck engines having a four valve exhaust system. In this arrangement the cam operated exhaust ports are operated with an asymmetrical timing relative to BTDC (Before Top Dead Center), but the intake ports are opened and closed symmetrically since they are controlled by the piston operation. During the downstroke the exhaust valves open before the intake ports to assure a blowdown of the relatively high cylinder pressure prior to the scavenging process. On the upstroke the exhaust valves are closed earlier than the intake ports to provide for an increased pressure and charge density in the cylinder prior to the compression event. This timing schedule provides for fairly high specific output. It is not conducive to high fuel efficiency because with a compression ratio, for example, of about 16:1, the expansion ratio would be only 14:1. The fuel efficiency of such engine is related to its expansion ratio.
Another problem that has deterred further development of the two stroke engine for midsize applications occurs at part load where less fuel and less air is required of the engine. If the engine designer were to reduce fuel delivery at part load, the same amount of air would still be pumped in by the constant speed compressor. This lack of proportioning results in misfirings of the engine.
SUMMARY OF THE INVENTION
The invention is a method and apparatus for decreasing fuel consumption in a variably loaded, two cycle internal combustion engine. The two cycle engine is of the type having an air chamber surrounding the working cylinder, the air chamber normally receiving pressurized air for supply to the working cylinder when the piston of the engine is in a preselected expanded position.
The method is characterized by decreasing the compression ratio of the engine by permitting communication between the working cylinder and the air chamber during the upward stroke of the engine up to about 85°-105° BTDC, during which the cylinder gases can flow back into the air chamber reducing engine friction as a result of a delay in the rise of the cylinder gas pressure during compression and a reduction in the peak compression pressure. This method particularly increases the efficiency of the two stroke cycle engine during part load conditions providing a compression ratio which is consistently greater than the expansion ratio and by eliminating the excess air problem.
In carrying out the method, it is preferable that the compression ratio be selectively reduced only during part or light load conditions corresponding to a part throttle position. This is desirably carried out by employing a butterfly valve in the channel providing supplementary communication between the air chamber and the working cylinder, the butterfly valve being normally closed during high load conditions to maintain the compression ratio at normal values and selectively opened during part load conditions to permit such communication. It is also desirable that the supplementary communication be provided by an auxiliary intake valve positioned in a channel in the head of the engine adjacent the exhaust valve, the channel communicating with the air chamber disposed about the sides of the cylinder sleeves.
To facilitate even greater decrease in fuel consumption for the above method, it is preferred that (a) the auxiliary intake valve as well as exhaust valves be driven by a mechanical desmodromic cam shaft system whereby the cam shaft is loaded with forces only required to operate the valves at momentary speeds, thereby reducing parasitic valve drive losses, (b) the air supply for the air chamber be generated by a blower driven by the engine output shaft through a differential mechanism effective to provide a blower speed and air flow output proportional to engine torque output during the lower speed range of engine operation and proportional to engine speed during high speed, high load conditions, and (c) the coolant pump be driven by the air blower drive shaft causing the coolant flow to the proportional to the mass air flow delivered to the engine and thereby eliminating excessive coolant pump power absorption under light load conditions.
It is advantageous that the opening and closing of the intake and exhaust valves as well as the opening and closing of the auxiliary intake valve be arranged to provide a compression ratio of about 10:1 and an expansion ratio of about 13:1.
With respect to the apparatus, a primary feature consists of mechanical means that provide, during part load engine conditions, a fluid communication between the trailing end of the working cylinder and the air supply for a preselected period after the intake and exhaust valve have been closed. Such means effects a delay in the rise of the cylinder pressure during the initial period of the upward stroke and promotes a reduction in the peak compression pressure to reduce engine friction.
The compression ratio reducing means preferably takes the form of a channel communicating the working chamber through the head of the engine with air supply chambers surrounding the side walls of the working cylinder sleeves. The channel is cyclicly opened and closed by an auxiliary intake valve positioned adjacent the other valves in the head of the working cylinder. The auxiliary intake valve is preferably actuated by a desmodromic drive. The channel is normally closed by a butterfly valve during full load conditions and opened by such valve during part load conditions.
Fuel consumption can be further decreased by combining the above apparatus feature with the additional feature of a variable drive mechanism for the air supply or blower. The variable drive assures that the mass airflow of the blower will be proportional to engine torque during the lower speed range of engine operation and, when high speed, high load conditions are desired, the mechanism provides for mass airflow proportional to speed of the engine. The differential drive mechanism may preferably take the form of a planetary gear set interposed between the engine output shaft and the transmission input shaft; the engine output shaft driving the planet carrier, the ring gear driving the transmission, and the sun gear, through an additional gear set, driving the blower. Under high speed, high load conditions, a lockup clutch is used to remove relative movement between the ring gear and planetary drive gear, thereby providing a direct drive to the transmission to force the blower speed to be proportional with engine speed.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevational view of a two stroke automotive engine employing the features of this invention, portions thereof being shown in cross-section and other portions being shown in schematic form;
FIG. 2 is a sectional view of the upper portion of FIG. 1 taken substantially along another section line;
FIG. 3 is a timing diagram illustrating the opening and closing of the various valves with respect to one reciprocal movement of the piston; and
FIG. 4 is a graphical illustration of working cylinder pressure as a function of piston travel for a single cycle of the apparatus of FIG. 1.
DETAILED DESCRIPTION
In a two stroke cycle engine 10, as shown in FIG. 1, the piston 11 is used for power production in every downstroke rather than in every other downstroke as in a four stroke cycle engine. This improves mechanical efficiency and facilitates the use of a lesser number of cylinders. Typically, two exhaust valves 12 and 13 are accommodated in the cylinder head 14. The intake ports 15 are arranged as a plurality of openings in the side wall 16 of the cylinder sleeve and are arranged circumferentially around such sleeve so that the ports will be uncovered or opened by the piston when near bottom dead center position (it is shown in the top dead center position). Thus, in typical operation of a two stroke cycle engine, the piston will reciprocate within the working cylinder 17 between a top and bottom position, every downstroke being a power stroke and every upstroke being a recovery stroke. During compression and expansion, the exhaust and intake ports are closed. When piston 11 reaches a position of about 115° ATDC (After Top Dead Center), see FIG. 3, the exhaust valves 12 and 13 will open ports 18 and 19. At about 123° ADTC (see FIG. 3), the intake ports 15 will be uncovered. These conditions will prevail until the exhaust valves close at about 150° BTDC (Before Top Dead Center). The intake ports are covered again by the piston at about 130° BTDC. The intake ports, being tied to the operation of the piston, will have their opening and closing symmetrical with respect to the operation of the piston.
Air is pumped into the intake ports from an air chamber 20 having walls 21 which form a jacket about the side walls of the cylinder sleeves 16 and the cooling jacket 36. The exhaust gases are expelled from the working cylinder 17 and fresh, pressurized air is introduced as supplied by the chamber 20 which receives pressurized air via duct 37 from a blower 22. The blower 22 is driven from the output shaft 23 of the engine through a differential drive mechanism 24.
To increase fuel efficiency, the expansion ratio is increased relative to the compression ratio. The compression process is only necessary to facilitate high expansion ratio before the cylinder pressure expands to below atmospheric pressure. This requirement can be satisfied in general with a compression ratio that is only 0.7-0.8 times as high as the expansion ratio. Such an arrangement, if embodied in a hardware with high mechanical efficiency, will provide for the highest fuel efficiency within other practical limitations. The reason it is desirable to minimize the compression ratio is that the work required during the compression stroke is only partially recovered during the expansion stroke, therefore the lower the compression stroke work, the lower the associated work loss.
A decrease in the compression ratio of the engine will facilitate a reduction in engine friction due to a delay in the rise of cylinder pressure and a reduction in the peak compression pressure. To accomplish this, means 27 for communicating the trailing end 25a of the working cylinder 25 with the air supply 26 is provided during part load engine conditions. Communication is maintained for a preselected period after the intake and exhaust ports have been closed. Maintenance of a gaseous communication between the air chamber 26 and the trailing end of the working cylinder 25 reduces the compression ratio. Preferably, the fluid communication is provided by way of a channel 28 which extends from an opening 29 in the roof of the working cylinder 25 through the head of the engine to a port 30 communicating with the top of the air supply chamber 20. To ensure that fluid communication is effective only during part load conditions, a butterfly valve 31 is preferably employed to permit communication during such part load conditions but to close off the fluid communication during high speed, high load conditions or maximum power conditions. The communication is also controlled with respect to each cycle of the piston; it is opened and closed by way of an auxiliary intake valve 32 actuated by a desmodromic drive 33 carried by the head 14 of the engine.
During a typical reciprocal cycle of the piston, the auxiliary intake valve 32 is actuated by the desmodromic drive to open at about 150° ATDC and remain open long after the intake ports and exhaust valves have been closed. The auxiliary valve 32 will then close at about 95° BTDC. The compression ratio is the difference between the volume of the working cylinder at the time when the auxiliary intake valve closes to its volume at the time the piston reaches top dead center; this is preferably designed to be about 10:1. The expansion ratio will be approximately 13:1 and is significantly greater than the compression ratio. The auxiliary intake port allows gases from the working cylinder to flow back into the air chamber and thereby reduce the effective compression ratio. The reduced compression ratio results in a favorable reduction in engine friction because the cylinder pressure will start rising only after a later point in the compression stroke and the peak compression pressure will be less than that corresponding to the 13:1 expansion ratio of prior art devices. This method of compression ratio reduction effectively reduces the amount of air trapped in the working cylinder. Whereas this is desirable for part load operation, it is not desirable when maximum power is required because the reduced quantity of trapped air proportionately reduces the attainable maximum power. This deficiency is eliminated by the closing of the butterfly valve whenever high or maximum output is required from the engine.
In conventional engines the intake and exhaust valves are driven in their opening strokes by a cam and returned to a closed position by strong springs designed to attain designed closing velocities even beyond the maximum rate of speed of the engine. This arrangement necessitates a drive torque requirements for the cam shaft significantly higher than required purely for the opening and closing of the valves. Even at low speeds, when the acceleration requirements are low, the cam shaft must compress the highly loaded springs through a mechanism of low mechanical efficiency. Only a fraction of the spring compression work is recovered during the valve closing event.
In this invention, additional engine friction reduction is provided by the combined use of the desmodromic drive 33 to actuate the head valves including the auxiliary intake valve 32. By use of the desmodromic drive 33, the cam shaft 38 is loaded only with the forces required to operate the valves at the momentary speed. Thus, at low speeds significant parasitic losses are saved. The desmodromic drive (as shown in FIG. 2) consists of a first cam 39 on the cam shaft 38 which when rotated actuates a lever 42 having another arm 43 which in turn raises the valve stem 41 to a closing position. The first cam 39 is arranged in combination with another cam surface 44 which when rotated acts directly on the top 41a of the valve stem to create an opening force. This arrangement facilitates much faster acceleration rates and the cam shaft drive torque requirement is significantly reduced at lower speeds.
It has been discovered that a further synergistic reduction in engine friction can be achieved in combination with the above features by use of a differential drive mechanism 24 for the air blower so that during part load conditions the blower will be operated proportional to the engine torque. But when maximum torque conditions are experienced, the differential drive mechanism will be shifted to a condition whereby the blower output will be proportional to the speed of the engine.
It is preferable that such differential means 24 to drive the blower take the form of a planetary gear set interposed between the engine output shaft 23 and the transmission input shaft 45. The engine output shaft drives the planet carrier 46 by way of input shaft 47 and plate 48. The ring gear 49, driven by the planet gear 52, drives the transmission input shaft 45. The sun gear 50, driving through an additional gear set 55, 51, 57, to drive the blower 22. This gear set will deliver at all times a certain predetermined fraction of the engine torque to the sun gear 50. The rest of the torque fraction is delivered to the transmission. This relationship is advantageous at low load conditions when the airflow requirements are low. The engine torque is low, therefore, the blower speed automatically drops off. When the output torque requirement increases, a higher fueling rate will increase the engine torque, thus higher torque will be delivered to the sun gear, causing the blower to speed up. For very high torque output, supercharging pressures will be generated with fast response time. This supercharging capability does not penalize part load fuel economy by high blower speeds at light loads.
Under maximum torque conditions, as the engine speed increases, the blower airflow with this drive system will tend to remain constant in terms of pounds per hour, resulting in a drop in air/lbs. per cycle. To eliminate this undesirable aspect, a lockup clutch 53 is employed which is actuated as about 50-60% of maximum engine speed, converting the drive of the blower to one which is proportional to engine speed. The ring gear 49 and planetary gear 52 will be locked up, forcing a one-to-one ratio drive to the sun gear 50 as this gear is coupled to gear 55 through sleeve 56 and the other gear set 51, 57. The blower drive gear 57 will be driven proportional to engine speed. In passenger car operation this mode would be used infrequently, typically only for heavy, high speed accelerations. Since the differential blower drive results in a slight drop of engine speed when the output torque requirement is reduced at constant vehicle speed, this automatically varies the N/V ratio which is beneficial for both fuel economy and driveability.
In prior art engines the engine coolant pump is driven off the crankshaft with a fixed drive ratio. This arrangement provides for higher than necessary coolant flow rates at part loads thereby wasting energy. The fuel flow rate and the cooling requirements are roughly proportional to the mass airflow rate therefore it is desirable to drive the coolant pump in proportion to the mass airflow rate. This is accomplished in this invention by attaching the cooling pump drive to the blower driveshaft 23, thereby making the coolant flow rate proportional to the mass airflow that is being delivered to the engine. This arrangement eliminates excessive coolant pump power absorption under light load conditions.
The essence and the intent of this invention can also be accomplished by applying alternative means to closing channel 27, 28 during high load operation. One of these means could be a deactivating mechanism for the activation of the auxiliary valve 33 such that under high load conditions the auxiliary valve remains spated throughout the entire engine cycle. Another alternative means can be a variable valve timing or variable valve event mechanism which would advance the closing time of valve 33 for high load operation to occur no later than when the intake ports are being closed (130° BTDC in this example). Mechanisms for the purpose of valve deactivation and for the purpose of valve timing or valve event changes are known to those familiar with engine design and control technology. | A method and apparatus is disclosed for decreasing fuel consumption in a variably loaded, two cycle internal combustion engine. Fluid communication is provided between the working cylinder and air chamber during the upward stroke of the engine up to about 85°-105° BTDC, during which time the cylinder gases can flow back into the air chamber reducing engine friction as a result of a delay in the rise of the cylinder gas pressure during compression and a reduction in the peak compression pressure. | 5 |
FIELD OF THE INVENTION
The present invention is generally directed to implantable medical devices, in particular to a tool for implanting electrodes and their association wires.
BACKGROUND OF THE INVENTION
In 1755 LeRoy passed the discharge of a Leyden jar through the orbit of a man who was blind from cataract and the patient saw “flames passing rapidly downwards.” Ever since, there has been a fascination with electrically elicited visual perception. The general concepts of electrical stimulation of retinal cells to produce these flashes of light or phosphenes has been known for quite some time. Based on these general principles, some early attempts at devising a prosthesis for aiding the visually impaired have included attaching electrodes to the head or eyelids of patients. While some of these early attempts met with some limited success, these early prosthesis devices were large, bulky and could not produce adequate simulated vision to truly aid the visually impaired.
In the early 1930's, Foerster investigated the effect of electrically stimulating the exposed occipital pole of one cerebral hemisphere. He found that, when a point at the extreme occipital pole was stimulated, the patient perceived a small spot of light directly in front and motionless (a phosphene). Subsequently, Brindley and Lewin (1968) thoroughly studied electrical stimulation of the human occipital cortex. By varying the stimulation parameters, these investigators described in detail the location of the phosphenes produced relative to the specific region of the occipital cortex stimulated. These experiments demonstrated: (1) the consistent shape and position of phosphenes; (2) that increased stimulation pulse duration made phosphenes brighter; and (3) that there was no detectable interaction between neighboring electrodes which were as close as 2.4 mm apart.
As intraocular surgical techniques have advanced, it has become possible to apply stimulation on small groups and even on individual retinal cells to generate focused phosphenes through devices implanted within the eye itself. This has sparked renewed interest in developing methods and apparati to aid the visually impaired. Specifically, great effort has been expended in the area of intraocular retinal prosthesis devices in an effort to restore vision in cases where blindness is caused by photoreceptor degenerative retinal diseases such as retinitis pigmentosa and age related macular degeneration which affect millions of people worldwide.
Neural tissue can be artificially stimulated and activated by prosthetic devices that pass pulses of electrical current through electrodes on such a device. The passage of current causes changes in electrical potentials across neuronal membranes, which can initiate neuron action potentials, which are the means of information transfer in the nervous system.
Based on this mechanism, it is possible to input information into the nervous system by coding the information as a sequence of electrical pulses which are relayed to the nervous system via the prosthetic device. In this way, it is possible to provide artificial sensations including vision.
One typical application of neural tissue stimulation is in the rehabilitation of the blind. Some forms of blindness involve selective loss of the light sensitive transducers of the retina. Other retinal neurons remain viable, however, and may be activated in the manner described above by placement of a prosthetic electrode device on the inner (toward the vitreous) retinal surface. This placement must be mechanically stable, minimize the distance between the device electrodes and the neurons, and avoid undue compression of the neurons.
In 1986, Bullara (U.S. Pat. No. 4,573,481) patented an electrode assembly for surgical implantation on a nerve. The matrix was silicone with embedded iridium electrodes. The assembly fit around a nerve to stimulate it.
Dawson and Radtke stimulated cat's retina by direct electrical stimulation of the retinal ganglion cell layer. These experimenters placed nine and then fourteen electrodes upon the inner retinal layer (i.e., primarily the ganglion cell layer) of two cats. Their experiments suggested that electrical stimulation of the retina with 30 to 100 uA current resulted in visual cortical responses. These experiments were carried out with needle-shaped electrodes that penetrated the surface of the retina (see also U.S. Pat. No. 4,628,933 to Michelson).
The Michelson '933 apparatus includes an array of photosensitive devices on its surface that are connected to a plurality of electrodes positioned on the opposite surface of the device to stimulate the retina. These electrodes are disposed to form an array similar to a “bed of nails” having conductors which impinge directly on the retina to stimulate the retinal cells. Such a device increases the possibility of retinal trauma by the use of its “bed of nails” type electrodes that impinge directly on the retinal tissue.
The art of implanting an intraocular prosthetic device to electrically stimulate the retina was advanced with the introduction of retinal tacks in retinal surgery. De Juan, et al. at Duke University Eye Center inserted retinal tacks into retinas in an effort to reattach retinas that had detached from the underlying choroid, which is the source of blood supply for the outer retina and thus the photoreceptors. See, e.g., E. de Juan, et al., 99 Am. J. Ophthalmol. 272 (1985). These retinal tacks have proved to be biocompatible and remain embedded in the retina, and choroid/sclera, effectively pinning the retina against the choroid and the posterior aspects of the globe. Retinal tacks are one way to attach a retinal array to the retina.
The retina is extraordinarily fragile. In particular, retinal neurons are extremely sensitive to pressure; they will die if even a modest intraocular pressure is maintained for a prolonged period of time. Glaucoma, which is one of the leading causes of blindness in the world, can result from a chronic increase of intraocular pressure of only 10 mm Hg. Furthermore, the retina, if it is perforated or pulled, will tend to separate from the underlying epithelium, which will eventually render it functionless. Thus attachment of a conventional prosthetic retinal electrode device carries with it the risk of damage to the retina, because of the pressure that such a device could exert on the retina.
Byers, et al. received U.S. Pat. No. 4,969,468 in 1990 which disclosed a “bed of nails” electrode array which in combination with processing circuitry amplifies and analyzes the signal received from the tissue and/or which generates signals which are sent to the target tissue. The penetrating electrodes are damaging to the delicate retinal tissue of a human eye and therefore are not applicable to enabling sight in the blind.
In 1992 U.S. Pat. No. 5,109,844 issued to de Juan et al. on a method of stimulating the retina to enable sight in the blind wherein a voltage stimulates electrodes that are in close proximity to the retinal ganglion cells. A planar ganglion cell-stimulating electrode is positioned on or above the retinal basement membrane to enable transmission of sight-creating stimuli to the retina. The electrode is a flat array containing 64-electrodes.
Norman, et al. received U.S. Pat. No. 5,215,088 in 1993 on a three-dimensional electrode device as a cortical implant for vision prosthesis. The device contains perhaps a hundred small pillars each of which penetrates the visual cortex in order to interface with neurons more effectively. The array is strong and rigid and may be made of glass and a semiconductor material.
U.S. Pat. No. 5,476,494, issued to Edell, et al. in 1995, describes a retinal array held gently against the retina by a cantilever, where the cantilever is anchored some distance from the array. Thus the anchor point is removed from the area served by the array. This cantilever configuration introduces complexity and it is very difficult to control the restoring force of the cantilever due to varying eye sizes.
Sugihara, et al. received U.S. Pat. No. 5,810,725 in 1998 on a planar electrode to enable stimulation and recording of nerve cells. The electrode is made of a rigid glass substrate. The lead wires which contact the electrodes are indium tin oxide covered with a conducting metal and coated with platinum containing metal. The electrodes are indium tin oxide or a highly electrically conductive metal. Several lead-wire insulating materials are disclosed including resins.
U.S. Pat. No. 5,935,155, issued to Humayun, et al. in 1999, describes a visual prosthesis and method of using it. The Humayun patent includes a camera, signal processing electronics and a retinal electrode array. The retinal array is mounted inside the eye using tacks, magnets, or adhesives. Portions of the remaining parts may be mounted outside the eye. The Humayun patent describes attaching the array to the retina using retinal tacks and/or magnets. This patent does not address reduction of damage to the retina and surrounding tissue or problems caused by excessive pressure between the retinal electrode array and the retina.
Mortimer's U.S. Pat. No. 5,987,361 of 1999 disclosed a flexible metal foil structure containing a series of precisely positioned holes that in turn define electrodes for neural stimulation of nerves with cuff electrodes. Silicone rubber may be used as the polymeric base layer. This electrode is for going around nerve bundles and not for planar stimulation.
The retina is also very sensitive to heat. Implanting a retinal prosthesis fully within the eye may cause excessive heat buildup damaging the retina. It is, therefore, advantageous to implant an electrode array on the retina attached by a cable to heat producing electronics which are implanted somewhere outside the eye. If no electronics are implanted in the eye, it is necessary to run one wire for each electrode from the electronics package to the electrode array. These wires must be extremely thin. While grouping them together in a cable with a protective sheath provides some protection, the array and cable must be handled carefully to prevent damage to the electrode array or cable.
Published US patent application 2002/0099420, Chow et al. describes a surgical tool for implantation of a retinal electrode array. The Chow device is a tube which is placed into the eye and to the implant location. Then fluid flows though the tube pushing the electrode array into place.
SUMMARY OF THE INVENTION
The present invention is a surgical tool for implanting an electrode array and its connected cable within an eye. The insertion tool is used to aid the surgeon in pulling the electrode wire and array through the scull, four-rectus muscles of the eye, and the sclera. The insertion tool consists of a medical grade ABS material that is commonly used in various medical products.
The novel features of the invention are set forth with particularity in the appended claims. The invention will be best understood from the following description when read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the retinal electrode array assembly showing the electrodes and signal conductors as well as mounting aperture for tacking the assembly inside the eye, wherein both the array and its associated electronics are located inside the eye.
FIG. 2 is a perspective view of the retinal electrode array assembly showing the electrodes and signal conductors as well as mounting aperture for tacking the assembly inside the eye, wherein the associated electronics are located outside the eye.
FIG. 3 is a perspective view of the retinal electrode array assembly wherein the array is installed inside the eye and the associated electronics are installed outside the eye at some distance from the sclera wherein the feeder cable contains both a coiled cable leading between the electronics and the sclera and a series of fixation tabs along the feeder cable for securing the feeder cable by suture.
FIG. 4 is a cross-sectional view of the retinal electrode array, the sclera, the retina and the retinal electrode array showing the electrodes in contact with the retina.
FIG. 5 depicts a cross-sectional view of the retinal electrode array showing a strain relief slot, strain relief internal tab and a mounting aperture through a reinforcing ring for a mounting tack to hold the array in position.
FIG. 6 illustrates a cross-sectional view of the retinal electrode array showing a strain relief slot and a ferromagnetic keeper to hold the array in position.
FIG. 7 illustrates a cross-sectional view of the retinal electrode array showing a strain relief slot and a mounting aperture through a reinforcing ring for a mounting tack to hold the array in position, wherein the strain relief internal tab containing the mounting aperture is thinner than the rest of the array.
FIG. 8 is a perspective view of the preferred insertion tool, for inserting the array of FIGS. 1-7 , having an curved tongs and a spring base.
FIG. 9 is a mechanical drawing of an alternate embodiment of the insertion tool illustrated in FIG. 8 having straight tongs and a.
FIG. 10 is a perspective view of an alternate embodiment using a hinged base.
FIG. 11 is a perspective view of an alternate embodiment using curved tongs and a hinged base.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following description is of the best mode presently contemplated for carrying out the invention. This description is not to be taken in a limiting sense, but is made merely for the purpose of describing the general principles of the invention. The scope of the invention should be determined with reference to the claims.
FIG. 1 provides a perspective view of a preferred embodiment of the retinal electrode array (implanted by the surgical too of the resent invention), generally designated 2 , comprising oval-shaped electrode array body 4 , a plurality of electrodes 6 made of a conductive material, such as platinum or one of its alloys, but that can be made of any conductive biocompatible material such as iridium, iridium oxide or titanium nitride, and single reference electrode 6 A made of the same material as electrode 6 , wherein the electrodes are individually attached to separate conductors 8 made of a conductive material, such as platinum or one of its alloys, but which could be made of any biocompatible conductive material, that is enveloped within an insulating sheath 10 , that is preferably silicone, that carries an electrical signal to each of the electrodes 6 . “Oval-shaped” electrode array body means that the body may approximate either a square or a rectangle shape, but where the corners are rounded. The reference electrode 6 A is not necessarily stimulated, but is attached to a conductor, as are electrodes 6 . The electrodes could be used in another application as sensors to transmit electrical signals from a nerve. The electrodes 6 transmit an electrical signal to the eye while reference electrode 6 A may be used as a ground, reference, or control voltage.
Electrode array body 4 is made of a soft material that is compatible with the body. In a preferred embodiment array body 4 is made of silicone having a hardness of about 50 or less on the Shore A scale as measured with a durometer. In an alternate embodiment the hardness is about 25 or less on the Shore A scale as measured with a durometer. It is a substantial goal to have electrode array body 4 in intimate contact with the retina of the eye.
Strain relief internal tab 12 , defined by a strain relief slot 13 that passes through the array body 4 , contains a mounting aperture 16 for fixation of the electrode array body 4 to the retina of the eye by use of a surgical tack, although alternate means of attachment such as glue or magnets may be used. Reinforcing ring 14 is colored and opaque to facilitate locating mounting aperture 16 during surgery and may be made of tougher material, such as high toughness silicone, than the body of the electrode array body to guard against tearing.
Signal conductors 8 are located in an insulated flexible feeder cable 18 carrying electrical impulses from the electronics 20 to the electrodes 6 , although the electrodes can be sensors that carry a signal back to the electronics. Signal conductors 8 can be wires, as shown, or in an alternative embodiment, a thin electrically conductive film, such as platinum, deposited by sputtering or an alternative thin film deposition method. In a preferred embodiment, the entire retinal electrode array 2 including the feeder cable 18 and electronics 6 are all implanted inside the eye. Electronics 20 may be fixated inside the eye to the sclera by sutures or staples that pass through fixation tabs 24 . The conductors are covered with silicone insulation.
Grasping handle 46 is located on the surface of electrode array body 4 to enable its placement by a surgeon using forceps or by placing a surgical tool into the hole formed by grasping handle 46 . Grasping handle 46 avoids damage to the electrode body that might be caused by the surgeon grasping the electrode body directly. Grasping handle 46 also minimizes trauma and stress-related damage to the eye during surgical implantation by providing the surgeon a convenient method of manipulating electrode array body 4 . Grasping handle 46 is made of silicone having a hardness of about 50 on the Shore A scale as measured with a durometer. A preferred embodiment of the electrode array body 4 is made of a very soft silicone having hardness of 50 or less on the Shore A scale as measured with a durometer. The reinforcing ring 14 is made of opaque silicone having a hardness of 50 on the Shore A scale as measured with a durometer.
FIG. 2 provides a perspective view of the retinal electrode array assembly 2 wherein the electrode array body 4 is implanted inside the eye and the electronics 20 are placed outside the eye with the feeder cable 18 passing through sclera 30 . In this embodiment, electronics 38 are attached by fixation tabs 24 outside the eye to sclera 30 .
FIG. 3 provides a perspective view of retinal electrode array 2 wherein electrode array body 4 is implanted on the retina inside the eye and electronics 38 are placed outside the eye some distance from sclera 30 wherein feeder cable 18 contains sheathed conductors 10 as silicone-filled coiled cable 22 for stress relief and flexibility between electronics 38 and electrode array body 4 . Feeder cable 18 passes through sclera 30 and contains a series of fixation tabs 24 outside the eye and along feeder cable 18 for fixating cable 18 to sclera 30 or elsewhere on the recipient subject.
FIG. 4 provides a cross-sectional view of electrode array body 4 in intimate contact with retina 32 . The surface of electrode array body 4 in contact with retina 32 is a curved surface 28 substantially conforming to the spherical curvature of retina 32 to minimize stress concentrations therein. Further, the decreasing radius of spherical curvature of electrode array body 4 near its edge forms edge relief 36 that causes the edges of array body 4 to lift off the surface of retina 32 eliminating stress concentrations. The edge of electrode array body 4 has a rounded edge 34 eliminating stress and cutting of retina 32 . The axis of feeder cable 18 is at right angles to the plane of this cross-sectional view. Feeder cable 18 is covered with silicone.
FIG. 5 provides a cross-sectional view of electrode array body 4 showing spherically curved surface 28 , strain relief slot 13 and mounting aperture 16 through which a tack passes to hold array body 4 in intimate contact with the eye. Mounting aperture 16 is located in the center of reinforcing ring 14 that is opaque and colored differently from the remainder of array body 4 , making mounting aperture 16 visible to the surgeon. Reinforcing ring 14 is made of a strong material such as tough silicone, which also resists tearing during and after surgery. Strain relief slot 13 forms strain relief internal tab 12 in which reinforcing ring 14 is located. Stresses that would otherwise arise in the eye from tacking array body 4 to the eye through mounting aperture 16 are relieved by virtue of the tack being located on strain relief internal tab 12 .
FIG. 6 provides a cross-sectional view of a preferred embodiment of electrode array body 4 showing ferromagnetic keeper 40 that holds electrode array body 4 in position against the retina by virtue of an attractive force between keeper 40 and a magnet located on and attached to the eye.
FIG. 7 is a cross-sectional view of the electrode array body 4 wherein internal tab 12 is thinner than the rest of electrode array body 4 , making this section more flexible and less likely to transmit attachment induced stresses to the retina. This embodiment allows greater pressure between array body 4 and the retina at the point of attachment, and a lesser pressure at other locations on array body 4 , thus reducing stress concentrations and irritation and damage to the retina.
FIG. 8 is a perspective view of the preferred insertion tool 50 . The electrode array body 4 and feeder cable 18 are extremely delicate. They must pass through a hole in the scull, pass under the four-rectus muscles of the eye, through the sclera and be attached to the retina. The insertion tool 50 has a rounded point 52 for gently separating muscle and flesh as the tool is passed through. The rounded point 52 is rigidly attached to a base 54 and top 56 . Both the base 54 and the top 58 are rounded on the outside and square on the inside. The rounding helps the tool pass through flesh without causing damage. The electrode body 4 is place between the base 54 and top 58 . Spring force traps the electrode array body 4 between the base 54 and top 58 . The tool further includes a radius 64 between the base 54 and the top 58 , which provides a space between the base 54 and the top 58 such that even pressure is applied along the length of the base 54 and the top 58 . The radius 64 reduces stress concentrations that could crack the tool at the junction of the base and top with the base and top are deflected while loading or unloading the electrode array. The even pressure allows a surgeon to hold the electrode array body 4 and feeder cable 18 firmly without causing unnecessary stress on the electrode array body 4 . The tool is fashioned from an inert biocompatible material that includes resilient elastic properties such ABS, stainless steel or titanium. ABS is suitable as a single use, disposable surgical tool while stainless steel or titanium could be steam sterilized and reused.
Once the electrode array body 4 and the feeder cable 18 are safely held in the surgical tool 50 , the surgeon can pass the tool 50 , electrode array body 4 and the feeder cable 18 in the same manner as a needle and thread. The preferred surgical tool 50 is curved to promote easy movement around the eye. The curvature of the tool generally conforms to the curvature of the outside of the sclera. Alternatively the surgical tool may be strait as shown in FIG. 9 .
FIG. 9 shows an alternate embodiment of the surgical tool 150 . The alternate surgical tool 150 has a strait base 54 and top 58 , while retaining the radius 164 and rounded point 152 of the preferred embodiment. There are advantages to strait and curved surgical tools for much the same reasons there are advantages to strait and curved needles. Different surgeons may prefer different tools.
FIG. 10 shows another alternate embodiment. Rather than relying on spring force to hold the electrode array body 4 and the feeder cable 18 in the tool 250 . The base 254 is rigidly attached to the rounded point 252 , but the top 258 is attached by a hinge 256 to the base 254 and rounded point 252 . This allows the surgeon more control of the force applied to the electrode array body 4 and the feeder cable 18 . The hinge 256 further provides for easier loading and unloading of the electrode array. This embodiment retains the radius 264 to provide even pressure along the lengths of the base 254 and the top 258 . This embodiment further includes notches 260 in the base 254 , which mate with guides 262 in the top 258 to hold the electrode array body 4 and the feeder cable 18 in the tool 250 , by holding the top 258 and base 254 together. The radius 264 reduces stress concentrations that could crack the tool at the junction of the base and top with the base and top are deflected while loading or unloading the electrode array.
FIG. 11 shows another alternate embodiment, similar to that shown in FIG. 12 . The base 354 is rigidly attached to the rounded point 352 , but the top 358 is attached by a hinge 356 to the base 354 and rounded point 352 . The hinge 356 further provides for easier loading and unloading of the electrode array. This embodiment retains the radius 264 to provide even pressure along the lengths of the base 354 and the top 358 . However, the base 354 and top 358 are curved to allow for easier insertion of the tool. This embodiment further includes a keeper 360 attached to the base 354 , which covers the top 358 to limit movement and prevents opening the tool and possibly dropping the array body 4 .
While the invention has been described by means of specific embodiments and applications thereof, it is understood that numerous modifications and variations could be made thereto by those skilled in the art without departing from the spirit and scope of the invention. | The present invention is a surgical tool for implanting an electrode array and its connected cable within an orbital socket. The insertion tool is used to aid the surgeon in pulling the electrode wire and array through the scull, four-rectus muscles of the eye, and the sclera. The insertion tool consists of a medical grade ABS material that is commonly used in various medical products. | 0 |
[0001] This is a continuation application of allowed application Ser. No. 10/065,927, having a filing date of Dec. 2, 2002, which is a continuation of International Application PCT/EP01/05754 with an international filing date of May 19, 2001, not published in English under PCT Article 21(2), and now abandoned.
BACKGROUND OF THE INVENTION
[0002] The invention relates to a flat material for manufacturing leaf-like sheets for receiving information, comprising at least one coating applied onto the sheet material, wherein the coating comprises fine cavities. The invention also relates to writing devices for sheet material with a coating in which magnetizable particles are embedded.
[0003] Numerous embodiments of flat sheet material for manufacturing leaf-like writing sheets are known wherein such sheets are provided as information carriers whose information contents is designed for optical recognition by means of toner particles applied to the surface. The information is generally in the form of a text comprised of letters or of graphic elements such as drawings or the like. The sheet is generally made of paper comprising cellulose fibers or plastic fibers embedded in a binder or made of a plastic film which is used, for example, for overhead projection. The application of the color is realized by hand with corresponding writing utensils or by printing devices. The information contents combinable on a sheet is generally limited by the readability of, for example, smaller letters.
[0004] With the increasing spread of computers, in particular, in office technology, the interaction of optical and electronic information carriers gains increasingly in importance. Modern computer-controlled laser and magnetographic printers enable a resolution of more than 1,000 dpi (dots per inch, dots per approximately 2.54 cm). However, the human eye recognizes only characters which are comprised of a plurality of such dots so that the resolution that is available for a maximum information contents cannot be used. On the other hand, it may be required to convert optically recognizable information into electronic information. For this purpose, text documents are placed onto a so-called scanner and scanned electro-optically. The resulting electronic image of the original requires a large memory space. By means of a subsequent OCR or OMR software (Optical Character Recognition, optical letter recognition; Optical Mark Reading, reading of handwritten or printed marks) the dot information read by the scanner can be converted into character or letter information which causes a significant reduction of the space required in the memory. However, this conversion is time-consuming and requires, according to the present state of the art, generally a manual correction.
[0005] A further possibility of conversion of optical recognizable electronic data can be realized by MICR (Magnetic Ink Character Recognition) wherein character recognition is carried out by sensing standardized magnetic fonts in a magnetic toner. According to a further known method, information can be optically recognized in the form of a so-called bar-code comprising a system of stripes of different width and different spacing to one another, for example, fixed on an adhesive label, which can then be scanned by a reading pen or hand-held or long-range scanners. A disadvantage of the aforementioned system is the permanency of once printed information.
[0006] The copying of text documents is usually performed by means of photocopying wherein the toner information on a written sheet is optically scanned and transferred onto a drum. In this connection, by means of the so-called magnetographic method the drum is locally magnetically conditioned such that on the corresponding locations of the drum a toner powder adheres and is applied as a copy of the original onto an additional sheet. However, soiling that occurs occasionally can negatively affect the quality of the copy.
SUMMARY OF THE INVENTION
[0007] The invention has the object to improve the exchange of electronic and optically recognizable data.
[0008] The object is solved by a flat sheet material having a coating in which electrically and/or magnetically activatable particles are embedded. The object is solved in regard to the writing device by a magnetographic writing head for a point-precise magnetic activation of the magnetizable particles or a hand-held pen with a magnetic tip.
[0009] In this connection it is suggested to embed in at least one coating of a flat sheet material electrically and/or magnetically activatable particles. The same or an additional coating has fine cavities, for example, in the form of a suitable crystalline structure and, in particular, in the form of microcapsules as they are known in the manufacture of carbonless paper. In particular, by embedding the electrically and/or magnetically activatable particles into the coating with cavities, these particles can be applied together with the coating in a common process onto the sheet material. Such a coating is suitable for large surface area, mass-produced articles so that in an inexpensive way large numbers of leaf-like sheets can be produced on which optical as well as electric or magnetic information or functions can be documented. As a result of the flat distribution, a high information contents by optical as well as, for example, magnetic means or a combination thereof can be recorded on the sheet material.
[0010] By means of the combination of optically readable and magnetically stored information, it is possible to produce with the sheet material according to the invention dialogue-capable products on which information can be recorded, changed, and retrieved.
[0011] The aforementioned particles are preferably arranged in the aforementioned cavities so that, independent of the contents of the cavities, the coating process can be realized by a method that is already known in mass production of carbonless paper without requiring greater modifications. The corresponding flat sheet material can be produced inexpensively in this way.
[0012] Depending on the type of application it can be expedient to configure the cavities and the microcapsules so that they are adapted to one another. For example, it can be expedient to fill the microcapsules with a dye and to embed it together with the electrically and/or magnetically activatable particles into the coating. Embedding of the electrical and/or magnetically activatable particles in a separate layer can simplify the manufacturing process. Also, it can be expedient to arrange the aforementioned particles in their own cavities or microcapsules and to introduce them, for example, as a mixture with microcapslues filled with dye, into the coating. In another advantageous variant, a cavity space contains the so-called dye and an electrically and/or magnetically activatable particle at the same time.
[0013] According to a further suggested solution a carbonless set is suggested in which the fine cavities contain a dye which, according to the known prior art, impinges on a dye coreactant when bursting and thus becomes visible. The corresponding coating contains also electrically and/or magnetically activatable particles so that in the carbonless set optically as well as magnetically recognizable information can be recorded separately from one another or so as to interact with one another. In an advantageous configuration the carbonless set is an endless set with a perforated tractor strip and in this way can be used in particular in the data output of computing devices of medium-sized data technology, personal computers, as well as automatic writing and labeling machines. In such devices, with a minimum expenditure optically as well as magnetically recognizable information can be output with great reliability and with correspondingly high output volume. In a further advantageous configuration the carbonless set is formed as a multi-part form set with which advantageously optically as well as magnetically recognizable data can be stored also. Such a multi-part form set has moreover only one parting edge as a result of which, after separation of the multi-part form set, three clean edges remain on the individual sheets which enables their use for representative purposes and particularly in business correspondence.
[0014] In an advantageous further development of the invention at least a portion of the cavities in the coating is filled with fragrant agents. For example, in connection with advertisement replies to be filled out, electronic money transfer forms for bills or the like, upon applying a writing device the cavities are crushed and the fragrant agent is released. A suitable fragrance which is perceived positively can increase motivation of the writer. The release can also be realized by activation of embedded electric or magnetizable particles. In a further advantageous embodiment at least a portion of the aforementioned cavities is filled with adhesives. In particular in connection with magnetizable or electrically activatable particles, envelopes produced in this way can be closed in an automated process.
[0015] In an advantageous embodiment, the sheet material is divided into zones which are coated with different coatings with differently filled cavities, respectively. In this way, for example, envelopes or the like can be produced which in one zone are provided with cavities filled with adhesive for automatic closing. In another zone having a coating in whose cavities dyes and magnetizable particles are arranged, an optically as well as magnetically readable address field can be provided. In this zone cavities with fragrant agents can be provided also which are released when filling out the address field.
[0016] In one suggested solution, cavities containing dyes as well as electrically and/or magnetically activatable particles are embedded in the coating of a flat sheet material. The latter activatable particles interact with the fine cavities in such a way that, for example, magnetic activation causes the cavities to burst so that the dye is released. In cooperation with a dye coreactant, as is known for carbonless sets, information is thus made visible in a magnetic way. For example, by means of a magnetographic printer or the like, letters, signs, bar-codes or the like can be magnetically applied onto the sheet material and can be made visible at the same time. In this way, the information contents is available in magnetically and optically recognizable form on the sheet material at the same time, and this enables an evaluation in an optical as well as electronic way.
[0017] In a preferred configuration the aforementioned particles are in the form of magnetizable particles. For a satisfactory data density a grain size of the magnetizable particles of smaller than approximately 2-3 micrometer has been found to be expedient. The magnetizable particles are made of materials conventional for diskettes or hard drives with hard-magnetic properties of high remanence and high coercive force and, in particular, made of chromium dioxide, iron oxide, polycrystalline nickel-cobalt alloys, cobalt-chromium alloy or cobalt-samarium alloy, or barium ferrite.
[0018] By way of targeted magnetization of the aforementioned particles it is possible to store information in binary form but also as text similar to an audio tape or a diskette. In particular, when the web or sheet material also comprises a paper layer, it can be written or printed on and in this way can carry optically recognizable information in addition to magnetically recognizable information. In this way, a plurality of advantageous possibilities result, in particular, with respect to dialogue capability. For example, the desired information can be stored magnetically and the web or sheet material can be provided with handwritten additional notes. Also, it is possible to record the same information in written as well as magnetic form on the web or sheet material so that, in this way, the possibility of direct reading by a viewer as well as the possibility of reading by a suitable magnetic sensing device for feeding into a computer are provided.
[0019] All mentioned embodiments are advantageously made of heat-resistant materials such that the corresponding sheets can be processed without quality loss in photocopiers, laser printers or magnetographic printers, and other devices with high heat development.
[0020] In a further suggested solution a sheet material with electrically and/or magnetically activatable particles is suggested which can be processed to notepad sheets with a self-adhesive strip. Such notepad sheets can be, for example, written on by a hand-held pen having a magnetic tip for taking down telephone messages or the like which are then recorded on such notepad sheets in a form that is optically recognizable as well as magnetically recognizable. Such a notepad sheet can be provisionally secured by means of a self-adhesive strip on a file folder or any other suitable location wherein the information contents, as needed, can be recorded later on by a magnetic scanner and processed further.
[0021] In particular, a simple copying action, for example, by means of a magnetographic printer that is only minimally modified, is possible by which, without using toner powder, a direct magnetization of the embedded particles is possible. When simultaneously employing a toner powder, the desired information can be recorded at the same time in a single working step so as to be recognizable magnetically as well as optically. In one embodiment with magnetizable particles and microcapsules filled with dyes, as they are known in connection with carbonless paper, the capsules can burst when exposed to pressure or heat and release the enclosed dye. The initially colorless dye then impinges on a dye coreactant which is provided in the coating with the cavities or at a surface on a carbonless sheet placed underneath. The interaction of the dye with the dye coreactant results in a visible copy. In connection with a suitable device this provides, for example, the possibility of writing on such a sheet only magnetically and to make the stored information visible subsequent to a dialogue process including different retrieval and change or correction processes.
[0022] The sheet material according to the invention enables in addition to the above described writing possibilities also additional manipulation possibilities as they are known from conventionally written-on paper sheets. For example, hole punching, stapling, filing and archiving as well as gluing or glue binding are possible as in the case of paper sheets. For this purpose, the sheet material, which is manufactured typically in an elongate form and wound onto rolls, is advantageously cut to the form of a sheet with a standardized basic surface area, in particular, the DIN A4 size (DIN=Deutsche Industrie Norm=German industrial standard), so that it can be processed in conventional printers, copiers and the like and can be archived in standard size file folders. Such a sheet or sheet material advantageously is divided into partial areas of which at least one is formed as a reading/writing area. A further partial area can be provided exclusively for the application of staples, punch holes or glue binding without impairing the stored magnetic information. The reading/writing area is expediently marked by printed markings so that the user can recognize without difficulties where suitable punch holes can be arranged.
[0023] In an advantageous variant the sheet material has strip conductors which can be printed on with a conducting dye and expediently are comprised of electrically conducting particles embedded in the aforementioned coating. The particles can be, for example, a metal powder and/or the aforementioned magnetizable particles which fulfill a double function as magnetic data storage means and as an electric transmission element. Expediently, the sheet material is divided into a plurality of reading/writing areas 12 which are connected each to a strip conductor. In this way, structures of the kind of a printed circuit board can be realized in which, for example, the magnetic information of an individual reading/writing area can be retrieved or changed at a remote location by means of a strip conductor.
[0024] Microchips, as they are used, for example, in the case of so-called Smart Labels, are also suitable as particles to be embedded into the coating. Such a microchip is expediently connected to the aforementioned strip conductors and enables, for example, an evaluation of the magnetic information stored in the individual reading/writing areas. In an expedient further development on the sheet material an antenna is applied, in particular, by printing, for data exchange with the activatable particles. The antenna can also be formed by the electrically activatable particles. In this way, the field of application of the sheet material is broadened in that the stored information, for example, when passing through a manufacturing process, can be read and/or changed at different locations with different means matched to the situation. For example, the aforementioned sheet material can be guided through a scanner-like device wherein the magnetic information can be sensed. At locations where such a direct access is not possible, the magnetically stored information can be retrieved by the aforementioned antenna, for example, in connection with a microchip, wherein the typical receiving distance is in the range of one meter. When in the context of passing through, a greater retrieval distances are required, the magnetic information, for example, can be made visible by means of the above described microcapsule-dye technology and can be optically sensed. For example, the information can be applied magnetically or optically as a bar-code wherein the optically recognizable bar-code can be read by means of a long-range scanner within a distance range up to approximately 10 m.
[0025] Products made of the inventive sheet material such as, for example, carbonless sets, forms, labels, waybills, election ballots, and much more are dialogue-capable and can thus be used in a variety of ways. The sheet material is printable on non-impact printers in several layers wherein the magnetic information can corresponds to the printed information but can also deviate therefrom. For example, in an intelligent waybill, the magnetic information during the course of the transport and an accompanying dialogue process can be matched to the respective actual status and, for example, can be made visible upon delivery.
[0026] In a further suggested solution, a mailing pouch and, in particular, an envelope are formed of a flat sheet material with electrically and/or magnetically activatable particles. For example, in connection with a magnetic writing device, such as a magnetographic printer or a hand-held pen with a magnetic tip, an address can be recorded optically recognizable for the mail person on such an envelope while the magnetically applied information applied at the same time can contribute to an improved automated letter delivery.
[0027] In a further suggested solution, a brochure is formed of the sheet material with the electrically and/or magnetically activatable particles. As a result of the simultaneous optic and magnetic writing possibility in a simplified way a so-called personalization of the brochure is possible in that, for example, personal or address data can be retrieved from a database and can be applied onto the brochure in a computer-controlled way so as to be magnetically and/or optically recognizable. For example, an advertisement brochure can be addressed personally to the individual client on the cover sheet while the magnetically recognizable information available at the same time simplifies an automated management and delivery to the client.
[0028] In a further suggested solution, a folder, in particular, for text documents, is formed of the sheet material with a coating containing electrically and/or magnetically activatable particles. Banks, insurance companies or the like can compile in such folders in a simplified way client-specific information and/or offers wherein the folder, on the one hand, discloses as optically recognizable printed text, for example, the addressee while the magnetically stored information stored at the same time in regard to this addressee simplifies an automated managing of this folder inclusive of the offers contained therein.
[0029] In a further suggested solution, the sheet material with electrically and/or magnetically activatable particles is processed to zigzag-folded stockform paper. Such a stockform paper can be used particularly advantageously in data processing devices when a large data volume must be recorded on paper without supervision. The zigzag-folded paper can be taken in and processed with suitable printers provided with a tractor device with high reliability wherein the desired information can be recorded on the stockform paper in an optically as well as magnetically readable form. For correspondingly large amounts of data, a further electronic processing is expedient which is assisted by the magnetic readability. At the same time, the optical readability provides for control by random sampling.
[0030] For application of the magnetic information on a sheet material with embedded magnetizable particles a writing device having a magnetographic printing head is suitable. By means of such a magnetographic printing head, as they are known from magnetographic printers, magnetizable particles can be conditioned precisely to a point along its longitudinal axis. By means of a relative movement of the sheet material relative to the magnetographic writing head transverse to its longitudinal axis, each individual point on the sheet material can be magnetized in the desired way in a fashion comparable to a laser printer or a photocopier. In this connection, very high writing speeds can be achieved and also a very high data density.
[0031] In an expedient configuration of the writing device two opposed magnetographic writing heads are aligned relative to one another and form an intermediate gap through which the sheet material can be guided. With the opposed alignment a high magnetic field strength and thus a reliable magnetic conditioning of the magnetizable particles in the sheet material can be achieved. Expediently, a magnetic reading device is arranged downstream with which the magnetic information on the sheet material can be read. In this way, a combination device for writing and/or reading is provided. In particular, with a suitable embodiment the magnetically written information can be immediately checked by the downstream magnetic reading device with regard to errors of the recorded magnetic data. This contributes to data safety in particular when the recordation of the information is carried out initially only magnetically without providing optical visibility and thus a control possibility.
[0032] The above described writing device is advantageously embodied as an add-on unit for a conventional printer. In this way, already present printing machines or also inexpensive workplace printers produced in mass production can be expanded with minimal additional expenditure such that the known data processing with optically readable information is expanded by the magnetically stored information. In a corresponding combination of the writing device and configuration of the sheet material large quantities of sheets can be inexpensively written on without toner, ink and the like in an optically and magnetically readable way.
[0033] Moreover, it is suggested to configure a writing device in the form of a hand-held pen which has a magnetic tip. For example, in connection with, self-dying paper with such a hand-held writing device ink in the same way as with a pencil or ballpoint pen information can be written onto the paper in an optically readable way wherein by means of the magnetic tip the same information is also applied magnetically for automated data recognition. With such a writing device, for example, election ballots, bank orders, or the like made of a corresponding sheet material can be written on by hand, and can be evaluated subsequently in large numbers reliably and at high speeds by means of a magnetic reading device. The pen-shaped writing device, depending on the application, can have a pure magnetic tip or a combination of magnetic tip and, for example, a ballpoint pen refill or the like.
[0034] A suitable sheet material can be produced, for example, in that iron oxide is arranged within a kaolin/SBR latex layer and applied by doctor onto a paper substrate of, for example, 49 g/m 2 . In this connection, the magnetizable particles have typically a surface density of approximately 0.1 to 0.4 g/m 2 . A conventional CB coating (coated back) imparts to the sheet material additionally the properties of a known carbonless paper. In a further variant for manufacturing the sheet material magnetizable particles, for example, made of Mn—Zn-ferrite with a grain size of <3 micrometer are embedded by a conventional method for microcapsule formation in such microcapsules. The manufacture of microcapsules can be realized, for example, in an oil-based emulsion with gelatin and gum arabic. The emulsion can, for example, be applied by doctor or by printing onto the paper substrate. The printing method can be any known printing method and, in particular, rotogravure printing. The arrangement of magnetizable particles in the microcapsules prevents, in addition to the aforementioned advantages, also an undesirable dying of the sheet material. As a protection against bursting of the microcapsules upon application onto the paper substrate a suitable protective additive, for example, in the form of wheat starch can be applied. The surface density of the magnetizable particles is expediently in the range of 0.1 and 1.2 g/m 2 . In the case of separate coatings for the microcapsules and the magnetizable particles, any suitable coating sequence can be selected. It may also be expedient to arrange the layers on two different sides of the sheet material. For further processing of the sheet material and also for application of magnetizable information the further processing of the sheet material in the form of rolls can be expedient.
BRIEF DESCRIPTION OF THE DRAWINGS
[0035] FIG. 1 shows a perspective overview illustration of a printed and magnetically writable sheet.
[0036] FIG. 2 shows schematic illustration of a cross-sectional enlargement of the sheet of FIG. 1 , compiled with an additional sheet to form a carbonless set.
[0037] FIG. 3 is a cross-sectional illustration of a variant of the sheet according to FIG. 1 with magnetizable particles in microcapsules.
[0038] FIG. 3 b is a variant of the arrangement of FIG. 3 with magnetizable particles in a separate coating.
[0039] FIG. 4 shows a schematic illustration of an arrangement of reading/writing areas in connection with a microchip and a transmission antenna.
[0040] FIG. 5 a schematic illustration of an envelope with magnetizable particles.
[0041] FIG. 6 a schematic illustration of a personalizable brochure.
[0042] FIG. 7 a schematic illustration of a personalized folder.
[0043] FIG. 8 a schematic illustration of a notepad with self-adhesive strips and magnetically activatable particles.
[0044] FIG. 9 a schematic illustration of an endless set of sheet material according to FIG. 2 .
[0045] FIG. 10 a schematic illustration of a multi-part form set made of the sheet material according to FIG. 2 .
[0046] FIG. 11 a schematic illustration of a zigzag-folded stockform paper with magnetizable particles.
[0047] FIG. 12 a schematic overview illustration of a computer system for information processing with the sheets according to the invention.
[0048] FIG. 13 a basic illustration of a magnetic writing device.
[0049] FIG. 14 a variant of the writing device according to FIG. 13 .
[0050] FIG. 15 a basic illustration of a combination of writing and reading device.
[0051] FIG. 16 the arrangement according to FIG. 15 in connection with a conventional printer.
[0052] FIG. 17 a basic illustration of a writing pen with a magnetic tip.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0053] FIG. 1 shows a sheet 1 which has been cut from sheet material 2 and comprises a carrier layer 30 which is divided into two partial areas 10 , 11 . The partial area 10 extends along the longitudinal edge 28 and has punch holes 29 . The other partial area 11 forms a reading/writing area 12 and is marked by printed markings 13 . The sheet 1 can have any suitable size and in the illustrated embodiment has DIN A4 size.
[0054] FIG. 2 shows an enlarged detail view of a cross-section of a carbonless set 15 with a sheet 1 according to FIG. 1 , wherein the carrier layer 30 of the sheet material 2 is comprised of paper 31 ; any desired paper quality as well as paperboard or cardboard can be used. Onto the carrier layer 30 a coating 4 is applied in which cavities 3 and electrically and/or magnetically activatable particles 5 are embedded. The cavities 3 can be formed by a suitable crystalline configuration of the coating 4 ; in the illustrated embodiment, they are microcapsules 6 filled with a dye 7 . The activatable particles 5 can be carbon particles or other electrically conducting particles; in the illustrated embodiment, they are metallic magnetizable particles 9 . The sheet 1 is compiled with an additional sheet of sheet material 14 to form a carbonless set 15 wherein the sheet material 14 is coated with a dye coreactant 27 which in interaction with the dye 7 in the microcapsules 6 causes a coloration. The sheet material 14 can additionally be coated with a coating 4 corresponding to that of the sheet material 2 . The magnetizable particles are made of materials conventional for diskettes or hard drives with hard-magnetic properties of high remanence and high coercive force and, in particular, made of chromium dioxide and, for example, also of iron oxide, polycrystalline nickel-cobalt alloys, cobalt-chromium alloy or cobalt-samarium alloy, or barium ferrite. The grain size is approximately 2-3 micrometers. The employed materials are heat-resistant.
[0055] FIG. 3 shows a variant of the sheet material 2 in which different types of microcapsules 6 are embedded as a mixture in the coating 4 . A portion of the microcapsules 6 is filled with a dye 7 and a further portion of the microcapsules 6 with magnetizable particles 9 . The further portion of the microcapsules 6 is filled with the dye 7 as well as with corresponding activatable particles 5 . An additional portion of the microcapsules 6 contains, in addition to the magnetizable particles 9 , a fragrant agent 55 or an adhesive 56 , respectively. Moreover, the dye coreactant 27 is introduced into the coating 4 . The dye 7 or the fragrance 55 or the adhesive 56 .can be released from the cavities 3 by activation of the particles 5 . The dye 7 then impinges on the embedded dye coreactant 27 and thus becomes visible. The activation of the particles 5 can be realized magnetically or electrically and, in particular, by employing a heat effect. The sheet material 2 can be used as a single layer for receiving data of the magnetic kind and according to the above described microcapsules principle. The carrier layer 30 in the embodiment according to FIG. 2 can be made of paper 31 and in the illustrated embodiment is a film 32 of PET.
[0056] FIG. 3 b shows a variant of the arrangement according to FIG. 3 in which the carrier layer 30 is provided with two additional different coatings 4 , 4 ′. The coating 4 contains microcapsules 6 while the magnetizable particles 9 are arranged in the additional coating 4 ′. The carrier layer 30 is comprised in the illustrated embodiment of paper 31 . In regard to the other features and reference numerals, the arrangement of FIG. 3 b is identical to the arrangement of FIG. 3 .
[0057] FIG. 4 shows in a schematic illustration a section of a sheet 1 on which a plurality of reading/writing areas 12 are provided. In the area of these reading/writing areas 12 the activatable particles 5 in the form of magnetizable particles 9 are provided. The reading/writing areas 12 are connected by a strip conductor 16 with a microchip 8 , respectively. The strip conductors 16 can be glued on or can be printed on of a conducting dye; in the illustrated embodiment, they are formed of electrically conducting activatable particles 5 . The microchip 8 forms also an activatable particle 5 embedded into the coating 4 . The microchip 8 is arranged at the focal point of a printed antenna 17 via which the information contents of the reading/writing areas 12 can be transmitted onto a remote reading device (not illustrated). Text or, for example, bar-codes can be printed onto the reading/writing areas 12 , wherein, for example, the bar-code can also be stored magnetically with magnetizable particles 9 and can thus be retrieved by the antenna 17 . It is also possible to employ in addition to the known one-dimensional bar-codes two-dimensional bar-codes with corresponding increased memory density.
[0058] FIG. 5 shows a mailing pouch 39 in the form of an envelope 40 comprised of a sheet material 2 according to FIG. 1 . The mailing pouch 39 can be embodied in any suitable letter size or can also be sized as a packet pouch, package envelope of coated cardboard or the like. The sheet material 2 of the envelope 40 has two zones 57 , 58 which are provided with different coatings 4 . The zone 57 serves for automated closing of the envelope 40 wherein its coating 4 contains adhesives 56 and magnetizable particles 9 similar to FIG. 1 . On the opposite side, the envelope 40 has an address field which is formed by the additional zone 58 . Its coating 4 contains magnetizable particles 9 as well as dyes 7 and a fragrance 55 .
[0059] FIG. 6 shows a brochure 41 in which a stack of paper 31 is bound in a cardboard 49 . The cardboard 49 is formed as a sheet material 2 according to FIG. 1 with activatable particles 5 . Moreover, the paper 31 can also be embodied in the form of the sheet material 2 according to the invention. According to FIG. 7 , a personalizable folder 42 for proposals, insurance documents or the like is formed of the inventive sheet material 2 in the form of a coated cardboard 49 . FIG. 8 shows a notepad 51 made of the inventive sheet material 2 whose individual notepad sheets 54 have a self-adhesive strip 44 on a common edge 50 , respectively, with which the individual notepad sheets 54 are held together and with which an individual notepad sheet can be attached as needed to any suitable surface.
[0060] FIG. 9 shows an endless set 45 which is formed of a carbonless set 15 according to FIG. 6 . The individual layers of the sheet material 2 , 14 ( FIG. 2 ) of the carbonless set 15 are connected to one another in thee area of the perforated tractor edge 46 for a printer tractor, for example, by crimping, adhesive binding or by a multiflex binding. After completion of printing, the perforated tractor edge 46 can be separated along a perforation 52 .
[0061] FIG. 10 shows a multi-part form set 47 which is comprised of a multi-layer carbonless set 15 made of an inventive sheet material 2 according to FIG. 2 as well as an upper cover layer of paper 31 . The individual layers are glued together along an edge 50 ; the glued edge 50 can be separated along a perforation 52 for separating the individual layers.
[0062] FIG. 11 shows a zigzag-folded stack of stockform paper 48 made of sheet material 2 according to FIG. 1 . The sheet material 2 has lines 53 as well as a lateral perforated tractor edge 46 for a printer tractor.
[0063] FIG. 12 shows in a schematic illustration combined the essential components of an office computer device for combined optical and magnetic processing of the inventive sheets. For this purpose, as a central element a computer 115 is provided in which texts or graphic images are produced and are displayed on the corresponding monitor 120 during the processing phase. Optionally, a text already present on a paper sheet can be scanned by an electro-optical scanner 116 and can be sent by line 121 into the computer 115 for further processing. Finished texts can be printed by means of a printer 24 onto a sheet for optical recognition by a user.
[0064] In a manner which is comparable to the described optical processing with the illustrated system, magnetic information can be produced on the inventive sheet 1 ( FIG. 1 - FIG. 4 ) by means of a magnetic reading device 22 and a magnetic writing device 35 . The magnetic reading unit 22 and the magnetic writing device 35 are also connected by line 121 with the computer 115 , respectively. The magnetic information on a sheet 1 can be read by the magnetic reading device 22 and can be processed in the computer 115 and can be displayed on the monitor 120 . After processing, the resulting magnetic information can be written magnetically onto the sheet 1 by means of the magnetic writing device 35 which is, in particular, a modified magnetographic printer. With the illustrated arrangement a mutual conversion of magnetic to optically recognizable information and vice versa is possible. Magnetic information which is read, for example, by the magnetic reading unit 22 can be printed in an optically recognizable form by the printer 24 onto a sheet 1 . In addition, the printed sheet 1 can be subsequently provided with the corresponding magnetic information by the magnetic writing device 35 .
[0065] The illustrated individual devices combined to a system can also be combined, as needed, to combination devices. For example, a reading device for the inventive sheets 1 is expedient in which the optical scanner 116 and the magnetic reading device 22 are combined wherein both information types can be sequentially or simultaneously read, depending on the configuration of the device. Also, the printer 24 can be combined with the magnetic writing device 35 in a combination device. When employing the magnetographic method, for example, the magnetic information and, when using a toner, also the optically recognizable information can be applied simultaneously onto a sheet 1 .
[0066] A writing device may be advantageous with which by means of a combined magnetographic and thermodynamic process a sheet 1 according to FIG. 3 is sequentially written on magnetically and subsequently by activation of the microcapsules 6 ( FIGS. 2 and 3 ) which are filled with a dye. Moreover, combination devices of the magnetic reading device 22 and the magnetic writing device 35 , optionally in connection with an electro-optical scanner 116 and/or a printer 24 can be expedient. In this way, a copying device similar to a known photocopier can be provided. In all aforementioned device combinations optionally a control unit can be integrated so that a connection to a computer 115 is no longer required.
[0067] FIG. 13 shows in a basic illustration a section of a magnetic writing device 35 wherein a sheet material 2 with embedded magnetizable particles 9 is guided along a magnetographic writing head 18 . The magnetographic writing head 18 corresponds in its length approximately to the width of the sheet material 2 so that transversely to the transport direction 21 by means of the magnetographic writing head 18 each individual point on the sheet material 2 can be precisely magnetized. The sheet material 2 is pressed by means of a drum 19 against the magnetographic writing head 18 and transported by rotation in the direction of arrow 20 .
[0068] FIG. 14 shows a basic illustration of a variant of the writing device 35 according to FIG. 13 according to which two opposed magnetographic writing heads 18 are aligned with one another such that between them a narrow gap 33 remains. The sheet material 2 can be guided through the gap 33 in the transport direction 21 . The two opposed and aligned magnetographic writing heads 18 generate in the gap 33 a strong magnetic field in the direction of arrow 34 for conditioning the magnetizable particles 9 ( FIG. 2 and the following) in the sheet material 2 .
[0069] FIG. 15 shows in a principal illustration the important components of the magnetic writing device 35 wherein the magnetographic writing head 18 is arranged in a writing unit 37 such that the sheet material 2 can be guided past it by means of a plate 36 in the transport direction 21 . In a magnetic reading device 22 arranged downstream a reading head 38 is provided with which the magnetic reading unit 22 can read for itself or can be used as a control unit for the information written in the writing unit 37 .
[0070] FIG. 16 shows the writing device 35 according to FIG. 15 as an expansion of a conventional printer 24 which can be a laser printer or an inkjet printer. The printer 24 can also be a matrix printer wherein, in connection with, for example, the sheet material according to FIG. 2 and FIG. 3 and the above described dye microcapsule technology, an ink ribbon, toner or the like is no longer needed. The magnetic writing device 35 in the illustrated embodiment is arranged relative to the transport direction 21 of the sheet material 2 downstream of the printer 24 as a result of which, in addition to the optically recognizable lettering of the sheet material 2 in the printer 24 , magnetic information via the magnetic writing device 35 can be provided. It may be expedient to provide the magnetic writing device relative to the transport direction 21 upstream of the printer 24 so that, for example, a magnetic information on the sheet material 2 can be read first and, as needed, can be made visible by the printer 24 .
[0071] FIG. 17 shows a further embodiment of a magnetic writing device 35 which is in the form of a hand-held pen 25 . The pen 25 has a magnetic tip 26 for magnetic conditioning of the magnetizable particles 9 in the sheet material 2 ( FIG. 2 and the following). The pen 25 can be embodied, for example, as a combination device as a ballpoint pen or pencil in connection with a magnetic tip 26 . | A flat sheet material for manufacturing leaf-like sheets for receiving information has at least one coating applied onto a first side of a substrate. Magnetically activatable particles are embedded in the at least one coating. The magnetically activatable particles have a grain size that is smaller than about 3 micrometers. The magnetically activatable particles are iron oxide arranged in a kaolin/SBR layer. A carbonless set can be made from the flat sheet material. | 8 |
BACKGROUND OF THE INVENTION
The invention relates to a process and an apparatus for applying and impregnating fleece materials with viscous liquids.
A fleece material is herein to be understood in particular as meaning a structure of irregular texture, in which a hollow space structure nonuniformly distributed over the area is present. Such fleece materials can have as base material natural as well as artificially prepared fibres which are additionally stabilized by crosslinking with one another. Such structures are difficult to impregnate, in particular if the process of encapsulation is to take place very rapidly and without inclusion of air or gas.
Such a production stage is present for example in the manufacture of fibre-reinforced cellulose casings which are preferably prepared from a fleece web and viscose.
Cellulose casings are used for example in the packing of comestibles, in particular as sausage casings. In this area, a distinction is made between casings coated with viscose on one or both sides, depending on the way the application of viscose is carried out in the course of manufacture.
The form which is coated with viscose on both sides generally exhibits a better and more uniform encapsulation of the fibre fleece, provided it is possible to avoid air inclusions in the short time of application of viscose to both sides of the fleece. It will be readily understood that the controlled displacement of air is easier to carry out in the case of a one-sided coating, in particular since, after leaving the die in which the coating is applied, there is still a free section, to the start of coagulation, which permits the one-sided displacement of air from the fleece.
On the other hand, there are areas where only fleece-reinforced cellulose casings coated with viscose on both sides are sued in practice. They are in general the fibre skins which have been lacquered on the inside with a barrier layer. The inner surface of the casing has a cellulose layer for reasons of lacquerability, while the outer surface has a cellulose covering for visual reasons. The customarily dope-dyed regenerated cellulose present on the outside provides optimal cover for the fibrous structure. This type of casings is widely used in the making of scalded and boiled sausages.
It has further been found that even in the case of unlaquered material there are in many areas significant advantages on the side of using material coated on both sides with viscose. For instance, in the event of high internal friction in the filling process the sliding behaviour with casings having an inside layer of cellulose is significantly more favourable on account of the excellent surface smoothness. Such is the case with uncooked sausage meat fillings or with skins for covering hams. Additional sliding impregnations which are necessary in the case of one-sided application of viscose to the outside can be dispensed with. The application of viscose to both sides also ensures a more uniform overall structure which is valued on account of the excellent peeling behaviour and the more uniform dilation of the casing in particular in the case of cold cuts which are packaged a second time.
These examples show the importance which two-sided coating with viscose already has and which will be increased if it is possible, in particular, to obtain the manufacturing advantages of one-sided coating with viscose. The two-sidedly viscose-coated cellulose casings in tube form which are customary today are manufactured, in general, by first forming a web of fibre fleece into a tube. This tube is coated on both sides with viscose in the coating means (GB No. 1336850). The viscose is applied almost simultaneously in this case because of the decrease in strength on wetting the customarily preferably used natural fibre fleece with viscose. Coating is effected with die systems which consist of an outer and an inner annular die. The viscose is applied under pressure via these annular dies in predetermined amounts. The reason it is difficult to impregnate the fleece without including air is that highly viscous aqueous liquids are concerned here.
The viscosity of the viscose is essentially determined by the solids content in terms of cellulose and the degree of polymerization. The higher these two values, the higher the viscosity. To process viscose, a low viscosity is desirable for rapid and optimal impregnation of the fibre fleece. However, the quality of the end product grows with a high solids content and degree of polymerization. The degree of polymerization determines the shrinkage behaviour and the elasticity of the regenerated cellulose, while the solids content determines the porosity and, in conjunction with the degree of polymerization, the final strength of the casting. The manufactured article is consequently a comprise which usually has a solids content which is actually too low.
To avoid the difficulties in the case of the twosided coating with viscose, the viscoses used have a solids content of 6.5 to 7% by weight, that is a solids content which is not optimal.
SUMMARY OF THE INVENTION
The present invention had for its object to provide an improved apparatus and improved process in particular for the two-sided coating of fleece materials.
The invention provides an apparatus for coating and impregnating fleece materials, in particular on both sides, with a viscous liquid, comprising preferably at least one applicator die on each side of the web of the fleece material, characterized in that on at least one web side A at least two dies D1 and D3 are arranged in a stagger in the transport direction. In a preferred embodiment, a die D2 is arranged for backcoating duty on web side I opposite to web side A, preferably between the dies D1 and D3.
In a particularly preferred embodiment, web side A is the outer web side of the fleece material. The dies are preferably annular slot dies whose exit opening has a width of 0.3 to 6 mm. The dies D1 and D3 are preferably staggered with respect to each other by about 2 mm to 8 mm.
The invention further provides a process for coating and impregnating fleece materials with a viscous liquid, in particular on both sides, comprising preferably at least one die for each web side of the fleece material, on at least one web side A the viscose fluid being applied by at least two dies D1 and D3. Die D3 is arranged in a stagger in relation to die D1 in the transport direction; the fleece is thus first coated by die D1 and only then by die D3. The backcoating of web side I is preferably carried out with a die D2, preferably situated opposite the die lip common to dies D1 and D3. In a preferred embodiment, application onto any desired area through die D2 takes place about 0 to 2×10 -2 seconds later than application through die D1. In a further preferred embodiment, the viscous liquid emerges from die D3 under a higher pressure than from die D1. In a very particularly preferred embodiment, the exit pressure from the die is controlled in such a way that the fleece web to be coated is moved by the staggered pressure build-up in the direction of the exit from the coating means.
The viscous liquid is preferably alkali cellulose (=viscose). It preferably has a viscosity of 300 to 500 falling ball seconds in particular from 350 to 400 falling ball seconds. In this connection, 310 falling ball seconds corresponds to 40,000 mPa.s. The solids content of the viscous liquid is preferably 7.5 to 9.0% by weight. The viscous liquid can contain additives which improve appearance and properties, for example coloured pigments, tackifiers or release agents, and also substances which regulate the adhesive and reactive properties.
The manufacturing process according to the invention for a cellulose casing preferably proceeds as follows:
The web, which is cut out of fibre fleece depending on the viscose tube diameter to be manufactured, is formed into a tube having an overlap. In the apparatus according to the invention, the tube is in this case preferably impregnated and coated on both sides with viscose. After passing through an air passage, the viscose-coated fibre fleece tube arrives in a coagulation bath, where the viscose is coagulated to obtain regenerated cellulose. The regenerated cellulose is then washed, passed through a softener bath and dried under supporting air. In this step, the amount of water to be evaporated is dependent on the level of the solids content in terms of cellulose in the viscose. Higher solids content means lower water content, which is thus a further reason for wanting to process high solids contents via a die.
The coating according to the invention is preferably effected in cascade style beginning with a coating of the outside via an annular die. By splitting up the outer viscose, the pressure on the fibre fleece is systematically increased, and on passing through the coating means the full pressure loading is only reached at the end of the annular gap which exists between the die bodies inside and outside relative to the fleece web guide. At the same time the fibre fleece is guided floatingly through the viscose and transported by means of an outflowing viscose through the die combination without significant exposure to friction. Astonishingly, as a result of splitting up the viscose the pressure increase on the fibre fleece is optimized in such a way that a tension-free structure of the viscose-coated material is obtained even in the case of thin fibre fleeces.
With the known manufacturing processes, it is customary for small and larger tension creases to form in the viscose tube. They are formed as a consequence of the tensile force acting on the viscose-coated tube underneath the die, caused essentially by friction from the dies in the application of viscose. They are a sign of production unreliability, can lead to unnecessary loss of production and interfere with the uniformly visual appearance of the completed product. These disadvantages can be avoided according to the invention.
A preferred apparatus according to the invention is described hereinafter with regard to the attached drawing wherein:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 depicts a cross-section through a coating apparatus
FIG. 2 depicts a die half with simplified viscose distribution
FIG. 3 depicts a magnified representation of the annular gap through which the fleece passes in the course of the coating.
DETAILED DESCRIPTION OF THE INVENTION
The application of viscose is effected in the apparatus of FIG. 1. The fibre fleece 4, formed into a tube, passes over a cylindrical calibrating mandrel 3. The tube passes between an outer die combination 1 and a corresponding inner die 2. The outer combination consists of two individual dies 5 and 6. The viscose is passed via a pump, not depicted, and feed line 7 into the annular chamber 9 of die 5, said annular chamber 9 being dimensioned in such a way that the pressure loss which occurs in the distribution of the viscose is negligible. The viscose, which is under pressure, flows via a narrow die slot 10 onto the fibre fleece. A similar outflow occurs from the second outer die 6 via feed line 8, annular chamber 11 and die slot 12. The feed lines 7 and 8 can be fed with viscoses having different properties. In the normal case, where a single type of viscose is used, a single feed line will be present, for example in annular chamber 11, and the feed to the second annular chamber 9 is effected via an adjustable annular opening 14 (FIG. 2). The adjustment of cross-section 14 is effected via a screw 13. In this way, it is a simple matter to effect an optimization of the splitting of the viscose during production.
Separately from the outer dies, the inner die 2 is fed via a viscose supply line, not depicted. Via the collecting space 15, the viscose passes into the die slot 16, and from there under pressure onto the fibre fleece 4.
FIG. 3 reveals the coating process and its working principle. The fibre fleece 4 first passes along the outer die lip 18 and is coated with viscose via die slot 10. The pressure is in general such that the viscose does not rise in annular gap 17 A. The high viscosity leaves deaeration channels free. In the zone of outer die lip 19 the backcoating is applied via inner die slot 16. Hence an encapsulation of the fleece is achieved without excessively high pressure. The inner die lip 21 ends below the die slot 10 for the purpose of giving optimal fleece support. The precoated fleece then passes into the pressure zone between die lips 19 and 20. The viscose flows on via die annular slot 12. Since the highest pressure drop is present along outer die lip 20, the viscose urges toward the exit via ring gap 17 E. Thereby the viscose moves the sensitive, now viscose-moist fibre fleece in the direction of die exit without imposing any stress on the fleece.
The advantages of the new coating system described over the customary dies particular are particularly large when employing viscoses of high viscosity, for example greater than 250 falling ball seconds. Particularly positive results are obtained in the range 300 to 500 falling ball seconds, where known processes are not satisfactory.
To obtain the cascadelike viscose loading with the wedge effect of the viscose pressure build-up, it is sufficient in practice to use the system described in the Example of double coating from the outside and single coating via the inner die. The reason the double coating is preferably on the outside is that these dies are more easily accessible for the viscose feed; the double coating system could of course also be positioned on the inside.
It is of course also possible to divide the viscose onto even more individual dies on the inside and outside if several viscose layers of different structures are required to obtain certain properties of the cellulose tube. In such an arrangement, the number of annular dies on the inside or outside can be an even or an odd number.
EXAMPLES
Example 1 (comparative example)
A fibre fleece of natural fibres having a paper weight per unit area of 21 g/m 2 and a cut width of 322 mm is coated with a conventionally produced viscose having the following data.
Solids content as cellulose: 7.7% by weight
Carbon sulphide used: 29% by weight on cellulose
Sodium hydroxide solution: 5.7% by weight
Degree of polymerization: 530
The viscosity of this viscose is 410 falling ball seconds at 20° C. This viscose is all but impossible to process at a manufacturing speed of 740 m/h using the customary viscose-coating system. Penetration is insufficient in the overlap area of the seam; air inclusions are visible. As a consequence of excessively high additional forces or frictional forces in the die the viscose is distributed highly unevenly on the fibre fleece. The completed product exhibits highly fluctuating bursting pressures.
Example 2
Example 1 is repeated, except that the viscose was applied according to the invention using an apparatus as depicted in FIG. 1. The coating speed was 750 m/h.
A smooth completely evenly impregnated cellulose tube is obtained.
The composition of the completed tube was:
18.1 g/m of cellulose
31% by weight of glycerol, relative to cellulose
7% by weight of water
The cellulose tube was subjected to a bursting test with water. The tube burst under a super atmospheric pressure of 0.69 bar.
The fibre fleece encapsulation exhibited no air inclusions.
The subsequent lacquering was easier to carry out on the particularly flat surface than was the case with material produced using viscose of low viscosity and the customary die system.
Example 3
Example 2 is repeated using a cellulose casing formed from a fibre fleece having a paper weight per unit area of 17 g/m 2 and a cut width of 200 mm. The same good results are obtained.
Example 4
A one-sided coating is carried out with the die combination D1 and D3. In this process, the cylindrical calibrating mandrel 3 serves to support the fleece tube until the coating with viscose is complete. A viscose is applied via die D1 in accordance with Example 1. The viscose has additionally been coloured. The same viscose is applied via die D3. Coating is carried out at a speed of 800 m/h on a fibre fleece having a cut width of 206 mm and a paper weight per unit area of 21 g/m 2 . A total fleece encapsulation is obtained with satisfactory impregnation of the seam. The layer of regenerated cellulose is uniform without colour stripes.
Example 5 (comparison)
The coating with the viscose is effected with the materials and the same processing speed as in Example 4. However, the die used is of the conventional type, having only one annular gap which is impinged on by viscose under pressure and via which viscose arrives on the fibre fleece.
In the case the cellulose skin does not exhibit complete incorporation of the fibres, unencapsulated fibres being clearly visible. The seam has not been sufficiently penetrated, and the casing breaks under pressure, which is why in addition an adhesive bonding of the seam is required in the viscose-coating process. The viscose distribution is nonuniformly distributed, as evident by the colour stripes. | Fleece materials are coated, in particular on both sides, with a viscous liquid by applying the viscous liquid to at least one side of a web from at least two dies. | 3 |
FIELD OF THE INVENTION
The invention relates to a device for adjusting bearing force of a pantograph of a railroad train set on a catenary wire.
It likewise relates to the process used in the device according to the invention.
BACKGROUND OF THE INVENTION
Very high-speed railroad train sets travel along some lines equipped as conventional catenaries of variable height. The contact force of the pantographs of these train sets on the catenary wires changes considerably when strong gusts of wind disrupt the collection of the current. At the present time, the speed of the train sets is reduced in the event of a meteorological warning announcing these gusts of wind.
It is therefore expedient to have a device allowing the pantograph to be made less sensitive to transitory squalls by controlling the force exerted on it.
A possible solution to this problem would involve executing a closed-loop control of the bearing force of the pantograph on the catenary wire. The aim would then be to design an electromechanical actuator device controlled permanently according to well-known control techniques. The actuator member can be electrical, hydraulic or preferably pneumatic.
However, in the specific context of railroad train set equipment, a closed-loop control device has a number of disadvantages of which the following may be mentioned:
the need for permanent energy consumption to maintain the control in respect of a pneumatic actuator, this resulting in an appreciable consumption of air,
possible problems of stability of the control and reliability of the elements of the closed loop,
the relative complexity of such a device and a high cost.
OBJECT OF THE INVENTION
The object of the invention is to overcome these disadvantages by providing a device for adjusting the bearing force of a pantograph of a railroad train set on a catenary wire, said pantograph having, at its upper end, a bow in mechanical and electrical contact with the catenary wire and being connected mechanically to actuator means exerting a nominal force on it at predetermined points and in a predetermined direction. Such a device must have a lower energy consumption and increased reliability.
SUMMARY OF THE INVENTION
According to the invention, this device comprises:
means for measuring the contact force between the bow and the catenary wire and for supplying information, corresponding substantially to the measured force, said measuring means being located in the immediate vicinity of the bow,
means for transmitting the measurement information from said measuring means into an appropriate zone of the railroad train set,
information-processing means for processing the transmitted information and set-point range signals, comprising a maximum force threshold signal, and for supplying logical control signals, and
control means for controlling said actuator means from said logical control signals when said measured contact force exceeds said maximum force threshold or in response to predetermined external control signals.
Thus, the device according to the invention makes it possible to achieve the abovementioned object of maintaining the bearing force of the pantograph within a predetermined force range, whilst at the same time making use of a simple open-loop system. There are available therefore a measurement, a comparison and a detection of a limiting contact force, the effect of these being a point control of the actuator means in the event of a deviation from the range of acceptable forces. Since the actuator means are controlled only if the set maximum threshold is crossed, this results in an energy saving and a great simplification of the control. Moreover, it is still possible to act directly on the actuator means, for example to raise and lower the pantograph, by means of external control signals.
According to a preferred version of the device according to the invention, the set-point range signals, processed by said information-processing means comprise, furthermore, a minimum force threshold signal, and said control means control said actuator means from said logical control signals when said measured contact force is below said minimum force threshold. This device thus ensures that the bow/catenary contact force remains above a minimum threshold, below which the risks of separation (misalignment) are considered excessive. The range of permissible contact forces is thus defined by both its upper limit and its lower limit.
According to another aspect of the invention, the process for adjusting the bearing force of a pantograph of a railroad train set on a catenary wire, used in the device according to the invention, the pantograph being connected to controlled actuator means exerting a nominal force on it at a predetermined point and in a predetermined direction, comprises,
a step of measuring the contact force between the bow of the pantograph and the catenary wire,
a step of comparing the measured force with a maximum contact-force threshold and of detecting the crossing of said maximum threshold, and
a step of changing the force setting of said actuator means, carried out when the measured contact force exceeds said maximum force threshold.
With this process, it has become possible to adjust the bearing force of the pantograph by having an instantaneous contact-force measurement which is compared with a maximum threshold. The change of the force setting, namely the reduction of the force exerted by the actuator means in relation to the nominal force, is affected only in the event of a detection.
In an advantageous version of the invention, the process comprises, furthermore, a step of comparing the measured force with a minimum contact-force threshold and of detecting the crossing of said minimum threshold, and furthermore the force setting of said actuator means is changed when the measured contact force is below said minimum force threshold.
As a result of this nominal minimum force threshold value, the reliability of collection is further improved, the increase in the force exerted by the actuator means taking effect only in the event that the crossing of the minimum threshold is detected.
In a preferred embodiment of the invention, the actuator means comprise at least one pneumatic cushion exerting an adjustable force on the pantograph by mechanical connection means and connected to the control means by electrically insulating pneumatic supply means.
The pneumatic cushion used as an actuator of the pantograph is thus at the potential of the pantograph. Insulating pneumatic supply means are therefore provided to ensure electric insulation between the actuator and the control means located inside the railroad train set. The device according to the invention is highly suitable for use in pneumatic actuator systems. In fact, a pneumatic cushion subjected to a nominal air pressure will maintain a specific force on the pantograph permanently without any other action. In the event of a gust of wind and the detection of a contact force of the bow outside the acceptable force range, the necessary reduction or increase of the force exerted on the pantograph will be obtained simply by bleeding or by supplying compressed air to the pneumatic cushion for a predetermined time.
In an advantageous version of the invention, the force-measuring means comprise a force sensor working by microcurvatures of optical fibers, which is mounted in the immediate vicinity of the contact strip of the bow, and the information-transmission means comprise a bundle of optical fibers connected, on the one hand, to the force sensor by connection means and, on the other hand, within the appropriate zone of the railroad train set, to the conditioning and filtering means comprising a unit for converting optical signals into electrical signals and a unit for filtering the converted signals.
The use of optical fibers in the force-regulating device according to the invention has the major advantage over any other system that it ensures perfect electrical insulation between the elements of the pantograph under high voltage and the control units located inside the railroad train set. Moreover, this type of optical-fiber sensor has very high sensitivity, a small overall size and a negligible mass in relation to that of the bow, this constituting a positive factor in view of the importance of having a movable assembly of as low a mass and therefore inertia as possible, in order to improve the dynamic behavior of the latter.
Furthermore, it has been proved that transmissions by optical fiber have a very high level of immunity to noise and to interference.
BRIEF DESCRIPTION OF THE DRAWINGS
Other particular features and advantages of the invention will also emerge from the following description. In the accompanying drawings given by way of non-limiting example:
FIG. 1 is a general diagrammatic view of a force-regulating device according to the invention,
FIG. 2 is a simplified descriptive view of a pantograph which can be equipped with a regulating device according to the invention,
FIG. 3 is a diagram illustrating the change in the mean bow/catenary contact force as a function of time when the device of FIG. 1 is used, where a gust of high intensity is concerned,
FIG. 4 is a diagram illustrating the change in the mean bow/catenary contact force as a function of time, where a gust of low intensity is concerned,
FIG. 5 is a diagrammatic view of an embodiment of an optical-fiber force sensor.
DETAILED DESCRIPTION OF THE INVENTION
The device 1 according to the invention comprises, referring to FIG. 1, a force detection device 31 located on the bow 3 of the pantograph 30 of a locomotive or, more generally, of a railroad train set.
The function of this force detection device 31 is to detect/measure the contact force Fc between the bow 3 and the catenary wire 2. It preferably uses at least one force sensor working by the microcurvature of optical fibers, which will be described later, or any other force sensor making it possible to detect two contact-force thresholds.
The pantograph 30 is equipped with a pneumatic-cushion balancing actuator 7 or any other controllable active balancing device which acts by means of an arm 6 of tubular structure on the pantograph 30.
Insulators 10a, 10b ensure, according to a well-known technique, electrical insulation between the pantograph 30 under high voltage and the structure of the train set 10.
The pantograph 30, illustrated by way of example in FIG. 2, is of the single-arm type under a voltage of 25 kV. It comprises a bow 3 having a framework and friction strips 51 equipped with sensors. It also possesses a base structure 35 allowing the pantograph 30 to be mounted on the roof of a railroad train set by means of flanges 52, 53 and 54 and having the pneumatic actuator cushion 7 and a main joint 34. It also possesses an upper arm 32 of tubular structure and lower and upper parallelogram bars 37, 38. The lower and upper arms 6, 32 are connected by means of a second main joint 33, the upper arm being connected to the bow 3 by means of a connection piece 39 and an upper joint 3a.
The balancing of the pantograph 30 is ensured by the pneumatic cushion 7 which acts in a known way on the lower arm 6 by means of a cam/sling system (not shown).
The device 1 according to the invention furthermore possesses, referring to FIG. 1, a control system 50 for the pneumatic cushion 7, at least one bundle of optical fibers 5 for carrying the information coming from the force sensor 31 and ensuring electrical insulation, a signal-processing system 60 comprising a bidirectional optical converter 13 and a filter device 14, and an electronic control unit 20. The pneumatic control system 50, the signal-processing system 60 and the electronic control unit 20 are arranged on the locomotive equipped with the device according to the invention. The bundles of optical fibers 5 are preferably accommodated inside tubular pieces 6, 32 of the pantograph 30 and are thus protected against the wind and the weather. These bundles of optical fibers 5 make the connection between the force sensor 31 and the electronic control unit 20 via the signal-processing system 60, whilst an insulating pneumatic pipeline 9 supplies the air necessary for actuating the pneumatic cushion 7 which is at the potential of the pantograph 30. An optical connector 4a is provided for connecting the bundle 5 to the force sensor 31 located on the bow 3.
A light source 61 is provided in order to transmit a light signal to a first group of optical fibers 62 which carries the light signal towards the force sensor 31. A second group of optical fibers 63 ensures the return of the optical information representing the bow/catenary contact force Fc towards the converter 13. The combination of the two groups of optical fibers 62, 63 forms the abovementioned bundle of optical fibers 5.
The pneumatic control system 50 comprises a pneumatic solenoid valve 11 of the 3/1 closed-center type controlled by two solenoid valves P1, P2, themselves supplied with signals transmitted by the electronic control unit 20. The 3/1 solenoid valve 11 controls the pressure in the pneumatic cushion 7 equipped with a safety valve 8. The pneumatic control system 50 possesses, furthermore, two solenoid valves P3, P4 connected in parallel and respectively ensuring the phases of raising and lowering the pantograph 30, which are controlled by means of signals coming from the electronic control unit 20, and a regulator 12 controlled via an electrical connection 25 by means of a module 28 of the unit 20 and intended for ensuring, in a known way, a predetermined law of static force f(v) on the bow 3 as a function of the speed V of the locomotive, the regulator 12 being connected to a compressor (not shown) by means of an air supply 73. When the solenoid valve P3 is not being supplied, the air flows directly from the controlled regulator 12 towards the part of the 3/1 solenoid valve 11 controlled by the solenoid valve P2. Conversely, when the valve P3 is activated, the air flows between these same two portions of the pneumatic circuit 50, but via a first flow limiter 72.
Similarly, when the solenoid valve P4 is deactivated (or activated), the air flows directly (or via a second flow limiter 71) from the part of the 3/1 solenoid valve 11 controlled by the solenoid valve P1 towards a connection to the atmosphere or bleed, 70.
The electronic control unit 20 ensures, on the one hand, the logical processing of the information on the detection of the crossing of the predetermined thresholds, coming form the force sensor 31 and conditioned by the signal-processing system 60, and, on the other hand, the control of the four solenoid valves P1, P2, P3, P4 of the pneumatic control system 50 as a function of said detection information and nominal operating values. The electronic unit 20 comprises a module 29 for processing the maximum force threshold Smax, which can generate a detection signal d(Smax) when the force sensor 31 has measured a force higher than the nominal value Smax, and a fault signal S A when an absence of force-signal transmission (attributable, for example, to a failure of the senor or to a break of the bundle) occurs. The electronic control unit 20 also possesses a module 23 for the logical processing of the signals D(Smax) and S A , the function of which is to generate control signals of the solenoid valves P1 and P4 and which also takes into account an external control D for the lowering of the pantograph 30. The module 23 will be designated hereafter as the lowering module.
The module 28 ensures the processing of the input signals: locomotive speed V, nominal minimum force threshold value Smin and the signal representing the force measured by the force sensor and preprocessed and shaped beforehand by the signal-processing system 60. This module 28 28 generates, in return, a control signal for the control regulator 12 and a signal for the detection of the minimum threshold d(Smin), the control signal of the regulator being in the abovementioned form of a predetermined law of static force f(v) as a function of the speed V of the locomotive. The signal representing the detection of the minimum threshold d(Smin) is applied to the input of a module 26 for the logical processing of the signal d(Smin) and a signal M demanding the raising of the pantograph 30, which, in return, generates two signals for the respective control of the solenoid valves P2 and P3 and which is designated hereafter as the raising module.
The lowering module 23 comprises a circuit 21 for generating a cutoff signal of predetermined duration from the detection d(Smax) of the crossing of the maximum force threshold (for example, a circuit of the monostable type), a first logical OR gate 22 having as inputs the fault signal S A and the external lowering control signal D, its output being connected, on the one hand, to the control line of the solenoid valve P4, and on the other hand, to one input of a second logical OR gate 24. The second input of this second logical gate 24 is the output of the abovementioned delay circuit 21, and it generates at its output the control signal of the solenoid valve P1.
The raising module 26 comprises a third logical OR gate 27 having as inputs the minimum threshold detection signal d(Smin) and the external raising control signal M and generating at its output the control signal of the solenoid valve P2, the solenoid valve P3 being controlled directly by the external raising control signal M.
The functioning of the limiting device according to the invention, at the same time as the process according to the invention, will now be described with reference to FIGS. 1 to 4.
When a strong gust of wind occurs in the region of the pantograph 30 and catenary wire 2, the contact force between the bow 3 and the catenary wire 2 increases considerably and, in the absence of a limiting device, can follow a trend, such as that shown by the curve 100 represented by broken lines in FIG. 3, where Fc denotes the contact force, the speed of the locomotive being assumed to be stabilized.
With the device according to the invention, the comparison made in the processing module 29 between the force measured by the force sensor and the nominal value Smax leads to a threshold detection and to a bleed of the pneumatic cushion 7 of a predetermined quantity of air for a predetermined time τ. This bleed is repeated until the mean measured contact force <Fc> no longer reaches the threshold Smax. When the gust abates, the contact force <Fc> decreases until the minimum force threshold Smin is reached.
This detection brings about the control of the inflation solenoid valve P2 in order to increase and restore the nominal pressure of the pneumatic cushion 7 and obtain a mean contact force contained within the range [Smin, Smax].
Where a weak gust of wind is concerned, it is possible that the minimum threshold will not be detected, as is illustrated in FIG. 4. After the last bleed of predetermined time τ, the measured contact force remains within the normal force range [Smin, Smax]. The nominal pressure is then restored systematically in the pneumatic cushion 7 after a predetermined waiting time T, this corresponding to the output signal of the module 28: d (Smin(T) (see FIG. 1).
In contrast, if a gust of wind causes a substantial misalignment of the bow 3, the minimum threshold Smin is detected first. The pressure of the pneumatic cushion 7 is then increased in successive stages so as to maintain the contact force above Smin until the gust has disappeared. The cushion 7 is subsequently returned to its nominal pressure as soon as the maximum-force detection signal appears or if the time lapse T has expired since the appearance of the last signal d(Smax).
The nominal threshold values Smax and Smin are preadjustable as a function of the type of catenary and of specific characteristics of the pantograph so equipped. To ensure good current collection, under all circumstances Smin should not be below a minimum value, for example of the order of 4 to 5 daN, always ensuring contact between the bow 3 on the catenary wire 2.
The limiting device 1 according to the invention likewise ensures an automatic lowering of the pantograph 30 in the event of a breakdown of information coming from the force sensor 31, which may be attributable to a fault occurring on the collecting head or to an accidental break of the optical bundle 5, and the normal functions of raising and lowering the pantograph 30.
Thus, if an external raising control signal is applied to the input M of the electronic control unit 20, the solenoid valves P2 and P3 are activated and lead to the pressurization of the pneumatic cushion 7 and therefore to the raising of the pantograph at a controlled speed. If, in contrast, an external lowering control is applied to the input D, whatever the value of the fault signal S A the logical gate 22 will transmit a logical level 1 at its output and the solenoid valves Pl and P4 will be controlled, causing the complete bleeding of the pneumatic cushion 7 and therefore the lowering of the pantograph at a controlled speed.
The functioning of the pneumatic circuit 50 will be understood better from a reading of the three operating examples given below:
1) Raising of the pantograph
During the raising of the pantograph, the solenoid valves P3 and P2 are supplied as soon as the raising signal M appears. The air at the desired pressure, coming from the controlled regulator 12, passes through the first flow limiter 72. For an adjustable time, the pantograph rises at the desired speed under the action of the pneumatic cushion 7 and gently comes up against the catenary wire 2. The solenoid valve P3 then switches and the cushion 7 is fed at full flow. The flow limiter 72 and the solenoid valve P3 therefore adjust the raising time of the pantograph.
2) Lowering of the pantograph
During the lowering of the pantograph, the solenoid valves Pl and P4 are supplied. The pneumatic cushion 7 under pressure is bled 70 by means of the solenoid valve Pl and the bleed flow is controlled by the second flow limiter 71 which the solenoid valve P4 has caused to take action in the circuit. The bleeding time is adjusted in such a way that P4 changes its state once the pantograph has reached its lower limit stops.
3) Detection of the threshold Smax under collection conditions
The 3/1 solenoid valve 11 controlled by the two solenoid valves P2 and P3 makes the pneumatic connections given in Table I, where 1 (or 0) indicates that the corresponding solenoid valve is (or is not) supplied by the electronic control unit 20.
______________________________________State of P1 State of P2 Pneumatic connections______________________________________0 0 Cushion 7 isolated0 1 Air admission to the cushion 71 0 Bleeding 70______________________________________
It is assumed that the pantograph 30 is in the collection position, that is to say that the raising phase (see example 1) is concluded. The solenoid valve P3 is deactivated: there is therefore a full flow at the air admission. The pressure in the cushion 7 is regulated to the nominal value. When the maximum threshold d(Smax) is crossed, the electronic control 20 switches P2 to 0 and sends a pulse signal of predetermined duration τ to P1, the effect of which is to relieve the cushion of a quantity of air necessary and sufficient to reduce slightly the bow/catenary contact force. This cycle is repeated as long as d(Smax) is present. When d(Smax) has disappeared, the nominal pressure is reintroduced into the cushion 7 upon the appearance of d(Smin) or if d(Smin) does not occur during the waiting time T, counted from the last information d(Smax).
Furthermore, the control regulator 12 ensures a modulation of the static force as a function of the speed V of the locomotive according to the predetermined law f(v).
In fact, the more the speed V increases, the more it is necessary to increase the major component of the contact force so as to ensure good collection, by making the dynamic phenomena relative.
FIG. 5 illustrates diagrammatically an effective embodiment of the force sensor based on the generation of microcurvatures of optical fibers arranged between two surface causing their deformation.
U.S. Pat. Nos. 4,618,764 and 4,572,950 disclose optical-fiber pressure detectors of this type and their disclosure is incorporated herein by reference.
An analysis of the phenomena involved shows that, within a particular adjustable force range, the loss of light energy attributable to the microcurvatures is a linear function of the stress load.
The force sensor 40 comprises at least one optical fiber 41 retained between a framework 43 and a thermal insulator 45, itself adjacent to the strip 51 of the bow. Screws 44a, 44b ensure a prestressing of the optical fibers 41.
Of course, the invention is not limited to the examples described and illustrated, and many modifications can be made to these examples, without departing from the scope of the invention.
Thus, other types of force sensors are possible, for example piezoelectric or strain-gage sensors, provided that they solve the critical problems of electrical insulation.
Other types of actuators of the pantograph, for example electromechanical actuators, can thus be provided. | A device (1) for adjusting the bearing force of a pantograph (30) of a railroad train set (10) on a catenary wire (2). The pantograph (30) has, at its upper end, a bow (3) in mechanical and electrical contact with the catenary wire (2), connected mechanically to an actuator (7, 34) exerting a nominal force on it at predetermined points and in a predetermined direction. A device (31) measures the contact force between the bow (3) of the pantograph (300 and the catenary wire (2) supplies information relating to the measured force. A transmitter (5, 4a) transmits the measurement information from the measuring device (31, 40) into an appropriate zone of the railroad train set (10). A processor (60, 20) processes the transmitted information and set-point range signals and supplies logical control signals. The actuator (6, 7) is controlled from the logical control signals when the measured contact force exceeds a predetermined maximum force threshold (Smax) or in responses to predetermined external control signals. | 1 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a division of prior application Ser. No. 10/207,428, filed Jul. 29, 2002 now U.S. Pat. No. 6,850,358, which claims priority to German patent application No. 101 37 154.3-42, filed Jul. 30, 2001. Both of these applications are hereby incorporated by reference herein.
FIELD OF THE INVENTION
The invention concerns a scanning microscope that defines an illumination beam path and a detection beam path, having an objective that is arranged in both the illumination beam path and the detection beam path.
The invention furthermore concerns an optical element having at least three ports, such that at one port an illuminating light beam can be coupled in, at a further port the illuminating light beam can be coupled out and a detected light beam can be coupled in, and at a third port the detected light beam can be coupled out.
BACKGROUND OF THE INVENTION
In scanning microscopy, a specimen is illuminated with a light beam in order to observe the detected light, constituting reflected or fluorescent light, emitted by the specimen. The focus of an illuminating light beam is moved in a specimen plane by means of a controllable beam deflection device, generally by tilting two mirrors; the deflection axes are usually perpendicular to one another, so that one mirror deflects in the X direction and the other in the Y direction. Tilting of the mirrors is brought about, for example, by means of galvanometer positioning elements. The power level of the detected light coming from the specimen is measured as a function of the position of the scanning beam.
The positioning elements are usually equipped with sensors to ascertain the present mirror position. The illuminating light is coupled in via a beam splitter. The fluorescent or reflected light coming from the specimen passes through the beam splitter and then arrives at the detectors.
In confocal scanning microscopy specifically, a specimen is scanned in three dimensions with the focus of a light beam.
A confocal scanning microscope generally comprises a light source, a focusing optical system with which the light of the source is focused onto an aperture pinhole (called the “excitation pinhole’), a beam splitter, a beam deflection device for beam control, a microscope optical system, a detection pinhole, and the detectors for detecting the detected or fluorescent light. The illuminating light is coupled in via a beam splitter. The fluorescent or reflected light coming from the specimen travels by way of the beam deflection device back to the beam splitter, passes through it, and is then focused onto the detection pinhole behind which the detectors are located. This detection arrangement is called a “descan” arrangement. Detected light that does not derive directly from the focus region takes a different light path and does not pass through the detection pinhole, so that a point datum is obtained which results, by sequential scanning of the specimen, in a three-dimensional image. A three-dimensional image is usually achieved by acquiring image data in layers.
The published German Patent Application DE 199 06 757 A1 discloses an optical arrangement in the beam path of a light source suitable for fluorescence excitation, preferably in the beam path of a confocal laser scanning microscope, having at least one spectrally selective element for coupling the excitation light of at least one light source into the microscope and for blocking the excitation light or excitation wavelength scattered and reflected at the specimen out of the light coming from the specimen via the detection beam path. For variable configuration with very simple design, the arrangement is characterized in that excitation light of differing wavelengths can be blocked out by the spectrally selective element.
Alternatively, an optical arrangement of this kind is characterized in that the spectrally selective element can be set to the excitation wavelength that is to be blocked out. Also stated in the aforesaid document is the fact that the spectrally selective element can be embodied as an acoustooptical tunable filter (AOTF) or an acoustooptical deflector (AOD).
The published German Patent Application DE 198 59 314 A1 discloses an arrangement of a light-diffracting element for the separation of excitation light and emitted light in a microscope beam path, preferably in a confocal microscope, and in particular in a laser scanning microscope, in which context both the excitation light and the emitted light pass through the light-diffracting element and at least one wavelength of the excitation light is influenced by diffraction, while other wavelengths emitted by the specimen pass through the element uninfluenced and are thereby spatially separated from the excitation light. The arrangement contains an AOTF.
The known scanning microscopes have the advantage of spectral flexibility as compared to scanning microscopes in which the separation of illuminating light and detected light is implemented with a beam splitter, since the acoustoopticai component can be set, by activation with sound waves of differing frequencies, to any desired optical wavelength for illuminating light or detected light. In addition, with these scanning microscopes the spectral separation is many times better than in scanning microscopes having beam splitters. The use of scanning microscopes having a beam splitter (which can be embodied, for example, as a neutral splitter) is preferred for reflective specimens, because of elevated light power losses in the acoustooptical components. Scanning microscopes having beam splitters are moreover considerably more economical.
Commercial scanning microscopes usually contain a microscope stand such as the one also used in conventional light microscopy. As a rule, confocal scanning microscopes in particular can also be used as conventional light microscopes. In conventional fluorescent incident-light microscopy, that portion of the light of a light source, for example an arc lamp, that comprises the desired wavelength region for fluorescent excitation is coupled into the microscope beam path by means of a color filter (called the “excitation filter”). Coupling into the beam path of the microscope is accomplished by means of a dichroic beam splitter that reflects the excitation light to the specimen while it allows the fluorescent light proceeding from the specimen to pass largely unimpeded. The excitation light scattered back from the specimen is held back with a blocking filter that is nevertheless transparent to the fluorescent radiation. Optimal combination of mutually coordinated filters and beam splitters into an easily interchangeable modular filter block has been usual for some time. The filter blocks are usually arranged in a revolving turret within the microscope, as part of so-called fluorescent incident-light illuminators, thus making possible rapid and easy interchange. A fluorescence device for inverted microscopes which contains a revolving mount for the reception of multiple fluorescence cubes which is mounted rotatably on a drawer is described e.g. in German Patent DE 44 04 186 C1.
SUMMARY OF THE INVENTION
It is therefore the object of the invention to propose a scanning microscope that is universally usable and that offers the advantages of the various known scanning microscopes. The scanning microscope is also intended to be retrofittable without, or in any case with little, alignment effort.
The above object is achieved by a scanning microscope comprising: an objective that defines an illumination beam path and a detection beam path and being arranged in both the illumination beam path and the detection beam path, an interchangeable module arranged in the illumination beam path and detection beam path that separates the illumination beam path and detection beam path at a fixed angular relationship to one another and that comprises at least a first acoustooptical component
A further object of the invention is to describe an optical element that is universally usable for the separation of illuminating and detected light beams.
This object is achieved by an optical element having at least three ports, such that at a first port an illuminating light beam can be coupled in, at a second port the illuminating light beam can be coupled out and a detected light beam can be coupled in, and at a third port the detected light beam can be coupled out, whereby the optical element contains at least a first acoustooptical component and is configured as an interchangeable module.
The invention has, in addition to the advantage of retrofittability, the further advantage of universal variability of the power level of the illuminating light of at least one arbitrarily selectable wavelength or at least one arbitrarily selectable wavelength region, also making possible low-loss reflection microscopy.
In a preferred embodiment of the scanning microscope, the acoustooptical component is configured as an acoustooptical tunable filter (AOTF). An embodiment having an acoustooptical deflector (AOD) can be implemented.
In another embodiment according to the present invention, an optical compensation element that compensates for a double refraction of the acoustooptical component, which results in a polarization-dependent spatial division of the detected light beam, is provided. The double-refraction properties are attributable to the crystal structure of the acoustooptical component. Because of the arrangement of their boundary surfaces, many acoustooptical components have an undesired prismatic effect on the detected light that, in a further preferred embodiment, is compensated for by an optical compensation element. The prismatic effect causes a spatially spectral division of the detected light beam. An embodiment in which the optical compensation element compensates both for an undesired prismatic effect and for a double refraction is very particularly advantageous. In this context, the optical compensation element preferably contains a further acoustooptical component. In a very particularly advantageous variant embodiment, the further acoustooptical component and the first acoustooptical component have the same external shape and the same crystal structure. The further acoustooptical component and the first acoustooptical component are oriented rotated 180 degrees from one another with reference to the propagation direction of the detected light beam striking the first acoustooptical component. As a rule, the further acoustooptical component oriented in this fashion is offset laterally with respect to the axis defined by the propagation direction of the detected light beam striking the first acoustooptical component, so that the detected light beam strikes the further acoustooptical component. In this embodiment, the spacing of the first acoustooptical component from the further acoustooptical component is selected to be as small as possible in order to prevent excessive spatial division of the detected light beam between the acoustooptical component and the further acoustooptical component. Spatial divisions on the order of half a beam diameter are acceptable.
In another embodiment, the further acoustooptical component is cemented, directly or via an intermediate component, to the first acoustooptical component.
The optical module preferably contains elements for beam guidance and elements for beam shaping. These are, for example, lenses, mirrors, gratings, concave mirrors, and glass blocks. Provision is made, in particular, for compensation for a beam offset or beam deviation created upon passage through the acoustooptical component.
In another embodiment, provision is made for temperature stabilization of the first acoustooptical component and the second acoustooptical component. In a further variant embodiment, in order to eliminate disadvantages due to temperature fluctuations or fluctuations in the wavelength of the illuminating light beam, provision is made for controlling the high frequency in open- or closed-loop fashion as a function of the temperature. Another variant provides, in order to realize this goal, for controlling the wavelength of the illuminating light beam in open- or closed-loop fashion as a function of the temperature.
In a preferred embodiment, a line multiplex is provided, a specimen being scanned several times but always with illuminating light of a different wavelength. An (automatic) switchover of the wavelength of the illuminating light for successive specimen lines is also possible.
In a very particularly preferred embodiment, guidance and banking elements for positioning the module are provided. These contain, for example, slide bars, dovetail guides, or a bayonet mount, which make possible simple and reliable introduction and positioning. Also provided are banking elements which define a working position of the module in the illumination and detection beam path and are configured so that the positioned coupling-out element is automatically aligned with respect to the detection beam path, and so that no further alignment of the coupling-out element is necessary after positioning.
In another embodiment, a revolving turret or a sliding carriage, which comprises at least one element receptacle, is provided for positioning of the module, the module being mounted on or in the element receptacle in such a way that the module can be positioned in the illumination and detection beam path by simply rotating the revolving turret or by sliding the sliding carriage. Alignment of the module is accomplished only once upon mounting of the module in or on the revolving turret or sliding carriage. The latter preferably comprises a snap-in apparatus that releasably immobilizes the revolving turret or sliding carriage when the module is positioned in the illumination and detection beam path. In a further variant embodiment, the revolving turret or sliding carriage comprises multiple element receptacles in which beam splitters, which are embodied as dichroic beam splitters, neutral splitters, or color beam splitters, are mounted. This approach according to the present invention is highly flexible, since the module and multiple different beam splitters of differing spectral properties can be held in readiness and easily interchanged.
In a particularly advantageous embodiment, the illuminating beam path coupled out of the module and the detected light beam coupled out of the module have parallel optical axes. This embodiment simplifies exchangeability with beam splitters based on plane-parallel substrates.
BRIEF DESCRIPTION OF THE DRAWINGS
The subject matter of the invention is depicted schematically in the drawings and will be described below with reference to the Figures, identically functioning elements being labeled with the same reference characters. In the drawings:
FIG. 1 shows an optical element according to the present invention;
FIG. 2 shows a scanning microscope according to the present invention;
FIG. 3 graphically shows the spectral properties of two optical elements;
FIG. 4 shows an optical element according to the present invention; and
FIG. 5 shows a further optical element.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows an optical element 1 according to the present invention. Optical element 1 comprises a first port 3 , a second port 5 , and a third port 7 ; at the first port 3 an illuminating light beam 9 is coupled in, at the second port 5 illuminating light beam 9 is coupled out and a detected light beam 11 is coupled in, and at the third port 7 detected light beam 11 is coupled out. Optical element 1 contains a first acoustooptical component 13 and is configured as an interchangeable module having a housing 15 . The incident illuminating light beam 9 is directed by a deflection mirror 17 onto first acoustooptical component 13 . Acoustooptical component 13 is configured as an AOTF that is traversed by an acoustic wave. The acoustic wave is generated by an electrically activated piezoacoustic generator. The frequency of the acoustic wave is selected so that only those components of illuminating light beam 9 of the desired wavelength are directed toward second port 5 . The other components of illuminating light beam 9 not influenced by the acoustic excitation are directed into a beam trap 19 . The power level of illuminating light beam 9 emerging from second port 5 can be selected by varying the amplitude of the acoustic wave; this is particularly advantageous in particular for applications in reflection microscopy. The crystal sectioning and orientation of acoustooptical component 13 are selected so that for the same coupling-in direction, different wavelengths are deflected in the same direction.
Optical element 1 makes it possible to vary the power level of illuminating light beam 9 , to vary the power level of at least one selectable wavelength or at least one selectable wavelength region of illuminating light beam 9 , and also to completely block out selectable wavelengths or selectable wavelength regions. Detected light beam 11 , which is depicted with dashed lines in the drawings, strikes acoustooptical component 13 in a propagation direction opposite to that of illuminating light beam 9 . Those components of detected light beam 11 having the same wavelength and polarization as those of illuminating light beam 9 are completely or partially (depending on the amplitude of the acoustic wave) directed onto deflection mirror 17 and then to first port 3 ; at decreased amplitude, the uninfluenced portion passes by deflection mirror 17 . If detected light beam 11 is, for example, reflected light, optical element 1 then acts as a variable neutral beam splitter whose splitting ratio is determined by the amplitude of the acoustic wave. If detected light beam 11 is fluorescent light whose wavelength is modified, for example, as a result of Stokes or Raman shifting, this light is not influenced by the acoustic wave and passes by deflection mirror 17 . Because of the double refraction of acoustooptical component 13 , detected light beam 11 is divided into an ordinarily and an extraordinarily polarized beam. In addition, the ordinarily and extraordinarily polarized beams are each also spectrally spread because of the prismatic effect of acoustooptical component 13 . An optical compensation element 21 , which comprises a further acoustooptical component 23 , is provided for compensation. Further acoustooptical component 23 corresponds in its construction to first acoustooptical component 13 . It is arranged rotated 180 degrees about the beam axis of 13 . As a result, the spread-out subbeams of differing polarization directions are recombined. At the same time, the spectral spreading of first acoustooptical component 13 is annulled. A slight parallel offset for detected light of different wavelengths does, however, remain. After passing through further acoustooptical component 23 , detected light 11 strikes a mirror pair made up of a first mirror 27 and a second mirror 29 . The purpose of mirror pair 25 is to bring detected light beam 11 onto the desired beam axis, i.e. the beam axis exhibited by detected light beam 11 that enters through second port 5 . This simplifies the interchangeability of optical element 1 with an element having a conventional beam splitter. With first acoustooptical component 13 or also with further acoustooptical component 23 , detected light beam 11 (like illuminating light beam 9 ) can be varied in spectrally selective fashion in terms of its power level.
FIG. 2 shows a scanning microscope according to the present invention that is embodied as a confocal scanning microscope, having two lasers 31 , 33 whose emitted light beams 35 , 37 , which have different wavelengths, are combined with dichroic beam combiner 39 into one illuminating light beam 9 . The scanning microscope comprises banking elements 41 , 43 which define a working position for an optical element 1 and a further optical element 47 that can be selectably introduced into said working position, and which make possible positioning with no need for alignment. Also provided is a guide element 45 that is embodied as a dovetail guide. Optical element 1 corresponds to the optical element illustrated in FIG. 1 . Further optical element 47 contains a dichroic beam splitter 46 for separating the illumination and detection beam paths. The particular optical element introduced into the working position directs the influenced or uninfluenced illuminating light beam 9 to a beam deflection device 49 that contains a gimbal-mounted scanning mirror 51 and guides illuminating light beam 9 through scanning optical system 53 , tube optical system 55 , and objective 57 over or through specimen 59 . Detected light beam 11 coming from the specimen travels in the opposite direction through scanning optical system 53 , tube optical system 55 , and objective 57 , and arrives via scanning mirror 51 at optical element 1 , 47 , which conveys detected light beam 11 to detector 61 , which is embodied as a multi-band detector. Illumination pinhole 63 and detection pinhole 65 that are usually provided in a confocal scanning microscope are schematically drawn in for the sake of completeness. Omitted in the interest of better clarity, however, are certain optical elements for guiding and shaping the light beams, as well as the drivers and connecting leads for the acoustooptical components. These are sufficiently familiar to the person skilled in this art.
FIG. 3 graphically shows the spectral properties of an optical element having a dichroic beam splitter, compared to an optical element having an acoustooptical component. The beam splitter is a triple dichroic optimized for the excitation wavelengths 488 nm, 543 nm, and 633 nm. A high reflectivity and correspondingly low transmission is required for these wavelengths. For efficient fluorescence detection, high transmission in the remaining wavelength region above the excitation lines is required. The detectable fluorescent light power level is obtained by integrating the product of the beam splitter transmission and the fluorescence spectrum over the wavelength region of interest. The transmission spectrum of an optical element having an acoustooptical component set to the same excitation wavelengths (488 nm, 543 nm, 633 nm) is also depicted.
FIG. 4 shows a module 66 according to the present invention having a first acoustooptical component that in this view is covered by its mount 67 , and having a further acoustooptical component 23 that is arranged in a mount 69 . The module comprises a housing 15 , a first port 3 , a second port 5 , and a third port 7 ; at first port 3 an illuminating light beam 9 is coupled in, at second port 5 illuminating light beam 9 is coupled out and a detected light beam 11 is coupled in, and at third port 7 detected light beam 11 is coupled out. Banking (locating) surfaces 71 , 73 for exact positioning are also provided. The module can be introduced easily and without alignment effort into an optical device, for example a scanning microscope or a flow-through cytometer, and can be interchanged, for example, with the optical element shown in FIG. 5 .
FIG. 5 shows an optical element that is equipped with a sliding carriage 75 in which multiple beam splitters 77 , 79 are stocked, and whose housing 15 has the same form as the module shown in FIG. 4 . The optical element can be introduced easily and without alignment effort into an optical device, for example a scanning microscope or a flow-through cytometer, and can be interchanged, for example, with the optical element shown in FIG. 4 .
The invention has been described with reference to a particular exemplary embodiment. It is nevertheless self-evident that changes and modifications can be made without thereby leaving the range of protection of the claims below. | A scanning microscope that defines an illumination beam path and a detection beam path, having an objective that is arranged in both the illumination beam path and the detection beam path, is disclosed. The scanning microscope is characterized by an interchangeable module that is also arranged in the illumination beam path and a [sic] detection beam path and that separates the illumination beam path and detection beam path at a fixed angular relationship to one another and comprises at least a first acoustooptical component. Also disclosed is an optical element having at least three ports. | 6 |
TECHNICAL FIELD
[0001] The present invention relates to a vehicle control device configured to achieve smooth vehicle travel, and is preferably applied to travel on a surface of a road such as an off road or a sloping road, which possibly generates vehicle travel resistance.
BACKGROUND ART
[0002] There has been conventionally disclosed in Patent Literature 1 a vehicle traction control device configured to reduce a tolerable slip (target slip) of a driving wheel in a case where an auxiliary transmission included in a four-wheel drive vehicle is in low gear in order to improve ground-covering properties on an off road. This device is configured to reduce the tolerable slip of the driving wheel and execute idling inhibitory control so as to achieve traction control (hereinafter, referred to as TRC (registered trademark)) in accordance with a driver's intention of emphasizing the ground-covering properties.
CITATION LIST
Patent Literature
Patent Literature 1: JP 2000-344083 A
SUMMARY OF INVENTION
Technical Problems
[0003] However, even if a tolerable slip is reduced and idling inhibitory control is executed, a vehicle cannot smoothly travel on an off road or a sloping road unless an accelerator pedal is pressed so as to overcome a surface gradient and road-surface resistance of a stepped road or the like. Specifically, a vehicle travel state changes constantly and a vehicle body is shaken largely on an off road such as a rocky road or on a steeply sloping road, so that a driver cannot perform appropriate accelerator operation. Particularly a driver not used to traveling on an off road tends to perform rough accelerator operation and excessively press the accelerator pedal. When the accelerator pedal is pressed excessively, an acceleration slip is generated at a wheel and TRC is executed to generate large braking force for acceleration slip inhibitory control and stall the vehicle. The vehicle accordingly behaves against a driver's intention with a vehicle stall despite the fact that the driver is pressing the accelerator pedal.
[0004] Off road travel causes a travel state in which the ground-covering properties are improved by applying braking force to transmit driving force from a slipping wheel to a different wheel and a travel state in which braking force is excessively applied when a slip stops to stall a vehicle and deteriorate the ground-covering properties.
[0005] Conventionally, a tolerable slip is reduced and larger braking force is applied to improve the ground-covering properties when an auxiliary transmission is in low gear. TRC not matched to an actual travel state may be executed to rather deteriorate the ground-covering properties of a vehicle.
[0006] In view of the above, it is an object of the present invention to provide a vehicle control device configured to execute TRC better matched to a vehicle travel state to improve ground-covering properties of the vehicle.
Solutions to Problems
[0007] In order to achieve the object mentioned above, according to claim 1 of the present invention, a vehicle control device includes: a target speed setting means for setting traction brake target threshold speed as target speed of wheel speed of the vehicle; and a TRC means for generating braking force with the service brake when the wheel speed exceeds the target speed and an acceleration slip is generated, to execute TRC of causing the wheel speed to approach the traction brake target threshold speed; wherein the vehicle control device further includes a brake control amount correction means for determining a degree of a stall prevention request of the vehicle, and reducing a brake control amount for generation of braking force by the TRC in a case where the degree of the stall prevention request is high in comparison to a case where the degree is low.
[0008] A driver tends to excessively press an accelerator during off road travel or the like, a slip may be generated at a wheel, and TRC may be executed. In this case, there are a travel state in which the ground-covering properties are improved by transmitting driving force from a slipping wheel to a different wheel and a travel state in which the slip stops and braking force is excessively applied to decrease vehicle body speed V 0 and deteriorate the ground-covering properties. The former is regarded as a travel state with a lower degree of the stall prevention request and the latter is regarded as a travel state with a higher degree of the stall prevention request. Accordingly, the brake control amount is corrected in accordance with the degree of the stall prevention request so as to be matched to a travel state. TRC better matched to the vehicle travel state is thus executed to improve the ground-covering properties of the vehicle.
[0009] According to claim 2 of the present invention, the brake control amount correction means determines that the degree of the stall prevention request is higher as vehicle body speed of the vehicle is higher, and reduces the brake control amount for generation of braking force by the TRC in a case where the vehicle body speed is high in comparison to a case where the vehicle body speed is low.
[0010] The degree of the stall prevention request can be determined in accordance with the vehicle body speed in this manner. A vehicle travelling at low vehicle body speed often travels on a road surface of high travel difficulty with a small degree of the stall prevention request. In this case, stronger wheel slip inhibitory control by brake control is thus executed to exert a limited-slip differential (LSD (differential gear unit)) effect, improve the ground-covering properties, and generate more deceleration, so that safety can be enhanced. If the vehicle body speed increases, it is considered that the vehicle has left a place of high travel difficulty and the degree of the stall prevention request is high. Switching is thus performed to reduce the brake control amount, so as to prevent failing to reach speed requested by a driver due to generation of large braking force under a condition where the driver intends to drive faster.
[0011] According to claim 3 of the present invention, the brake control amount correction means detects road-surface resistance of a road surface travelled by the vehicle, determines that the degree of the stall prevention request is higher as the road-surface resistance is higher, and reduces the brake control amount for generation of braking force by the TRC in a case where the road-surface resistance is high in comparison to a case where the road-surface resistance is small.
[0012] The degree of the stall prevention request can be determined in accordance with the road-surface resistance in this manner. With high road-surface resistance, the vehicle tends to stall when braking force is generated by brake control. The brake control amount is thus made smaller than that for a road surface with small road-surface resistance. Control can thus be executed in accordance with the road-surface resistance of the travel surface. Examples of the road-surface resistance include resistance due to a condition of a surface of a desert road, a muddy road, or the like, and gravity applied in the vehicle longitudinal direction due to inclination of a road surface.
[0013] According to claim 4 of the present invention, the brake control amount correction means determines, in accordance with an accelerator opening rate, that the degree of the stall prevention request is higher as the accelerator opening rate is larger, and reduces the brake control amount for generation of braking force by the TRC in a case where the accelerator opening rate is large in comparison to a case where the accelerator opening rate is small.
[0014] The degree of the stall prevention request can be determined in accordance with the accelerator opening rate in this manner. The brake control amount is increased because driving force is large at the beginning of accelerator operation. With continuous accelerator operation, a slip amount due to acceleration increases and braking force increases excessively. The brake control amount is thus made smaller than that at the beginning of the pressing operation. Control can thus be executed in accordance with the accelerator opening rate.
BRIEF DESCRIPTION OF DRAWINGS
[0015] FIG. 1 is a diagram depicting system configurations of braking and driving systems of a vehicle equipped with a vehicle control device according to a first embodiment of the present invention.
[0016] FIG. 2A is a flowchart of entire OSC.
[0017] FIG. 2C is a caption of FIG. 2A .
[0018] FIG. 2B is a flowchart of entire OSC subsequent to FIG. 2A .
[0019] FIG. 3 is a chart illustrating a method of setting engine target threshold speed.
[0020] FIG. 4 is a map of the relation between an accelerator opening rate and temporary engine target threshold speed TVEtmp 1 .
[0021] FIG. 5 is a flowchart of detailed processing of calculating accelerator operation amount requested driving force.
[0022] FIG. 6 is a flowchart of processing of calculating OSC brake target threshold speed.
[0023] FIG. 7 is a chart illustrating a method of setting second brake target threshold speed TVBtmp 2 .
[0024] FIG. 8 is a map of the relation between the accelerator opening rate (%) and accelerator acceleration ACCEL_G.
[0025] FIG. 9 is a map of the relation between accelerator close grade speed and a large deceleration period T.
[0026] FIG. 10 is a map of the relation between the accelerator opening rate (%) and a speed upper limit value ACCEL_UP.
[0027] FIG. 11 is a chart of the relation among vehicle body speed V 0 along with various conditions, a first brake coefficient TB 1 , a first threshold TV 1 , and an OSCbrake correction coefficient CB.
[0028] FIG. 12 is a map of the relation of a TRC brake coefficient correction value TBK and a TRC threshold correction value TVK to the accelerator opening rate (o).
[0029] FIG. 13 is a map of the relation of a second brake coefficient TB 2 and a TRC threshold TV 2 to road-surface resistance.
[0030] FIG. 14A is a timing chart of a case where a travel surface is a mogul road surface (an uneven surface with projections and recesses).
[0031] FIG. 14B is a caption of FIG. 14A .
[0032] FIG. 15A is a timing chart of a case where the travel surface is a desert road surface.
[0033] FIG. 15B is a caption of FIG. 15A .
DESCRIPTION OF EMBODIMENTS
[0034] The embodiments of the present invention will now be described below with reference to the drawings. It is noted that same or equivalent portions are to be denoted by same reference signs and described in the following embodiments.
First Embodiment
[0035] FIG. 1 is a diagram depicting system configurations of braking and driving systems of a vehicle equipped with a vehicle control device according to the first embodiment of the present invention. Described below is application of a vehicle posture control device according to an embodiment of the present invention to a four-wheel drive vehicle having a front drive base in a driving form provided with front wheels serving as main driving wheels and rear wheels serving as sub driving wheels. The vehicle posture control device is also applicable to a four-wheel drive vehicle having a rear drive base in a driving form provided with rear wheels serving as main driving wheels and front wheels serving as sub driving wheels.
[0036] As depicted in FIG. 1 , the driving system of the four-wheel drive vehicle includes an engine 1 , a transmission device 2 , a driving force distribution control actuator 3 , a front propeller shaft 4 , a rear propeller shaft 5 , a front differential 6 , a front drive shaft 7 , a rear differential 8 , and a rear drive shaft 9 . The driving system is controlled by an engine ECU 10 serving as an engine control means, or the like.
[0037] Specifically, when the engine ECU 10 receives an operation amount of an accelerator pedal 11 , the engine ECU 10 controls the engine so as to generate engine output (engine torque) required for generation of driving force according to the accelerator operation amount. This engine output is transmitted to the transmission device 2 and is converted at a gear ratio according to a gear position set by the transmission device 2 . The engine output thus converted is then transmitted to the driving force distribution control actuator 3 serving as a driving force distribution control means. The transmission device 2 includes a transmission 2 a and an auxiliary transmission 2 b . Output according to a gear position set by the transmission 2 a is transmitted to the driving force distribution control actuator 3 during regular travel. In contrast, when the auxiliary transmission 2 b is actuated during travel on an off road, a sloping road, or the like, output according to a gear position set by the auxiliary transmission 2 b is transmitted to the driving force distribution control actuator 3 . The driving force is then transmitted to the front propeller shaft 4 and the rear propeller shaft 5 in accordance with driving force distribution determined by the driving force distribution control actuator 3 .
[0038] Driving force according to driving force distribution for front wheels is applied to front wheels FR and FL through the front drive shaft 7 that is connected to the front propeller shaft 4 by way of the front differential 6 . Driving force according to driving force distribution for rear wheels is applied to rear wheels RR and RL through the rear drive shaft 9 that is connected to the rear propeller shaft 5 by way of the rear differential 8 .
[0039] The engine ECU 10 is configured by a known microcomputer including a CPU, a ROM, a RAM, an I/O, and the like. The engine ECU 10 executes various calculation and processing according to programs stored in the ROM and the like to control engine output (engine torque) and control driving force generated at the respective wheels FL to RR. For example, the engine ECU 10 receives an accelerator open degree in accordance with a known technique and calculates engine output from the accelerator open degree and various engine controls. The engine ECU 10 transmits a control signal to the engine 1 for regulation of a fuel injection amount and the like and control of the engine output. The engine ECU 10 can determine that the accelerator pedal 11 is ON if the accelerator open degree exceeds an accelerator ON threshold. There is provided in the present embodiment an accelerator switch 11 a configured to indicate whether or not the accelerator pedal 11 is operated. The engine ECU 10 detects that the accelerator pedal 11 is ON when receiving a detection signal from the accelerator switch 11 a . The engine ECU 10 also executes TRC. For example, the engine ECU 10 acquires information on wheel speed and vehicle body speed (estimated vehicle body speed) from a brake ECU 19 to be described later. The engine ECU 10 outputs a control signal to the brake ECU 19 so as to inhibit an acceleration slip indicated by a deviation therebetween so as to apply braking force to a control target wheel and decrease driving force. The acceleration slip is thus inhibited so as to accelerate the vehicle efficiently.
[0040] Although not depicted herein, the transmission device 2 is controlled by a transmission ECU and driving force distribution is controlled by a driving force distribution ECU or the like. These ECUs and the engine ECU 10 mutually exchange information through an onboard LAN 12 . According to FIG. 1 , the engine ECU 10 directly receives information from the transmission device 2 . The engine ECU 10 can alternatively receive gear positional information on the transmission device 2 outputted from the transmission ECU through the onboard LAN 12 , for example.
[0041] A service brake configuring the braking system includes a brake pedal 13 , a master cylinder (hereinafter, referred to as the M/C) 14 , a brake actuator 15 , wheel cylinders (hereinafter, referred to as the W/Cs) 16 FL to 16 RR, calipers 17 FL to 17 RR, disc rotors 18 FL to 18 RR, and the like. The service brake is controlled by the brake ECU 19 serving as a brake control means.
[0042] Specifically, when the brake pedal 13 is pressed and operated, brake fluid pressure is generated in the M/C 14 in accordance with a brake operation amount. The brake fluid pressure thus generated is transmitted to the W/Cs 16 FL to 16 RR through the brake actuator 15 . The disc rotors 18 FL to 18 RR are pinched by the calipers 17 FL to 17 RR so as to generate braking force. Such a service brake can be in any form if it is configured to automatically pressurize the W/Cs 16 FL to 16 RR. Exemplified herein as the service brake is a fluid pressure service brake configured to generate W/C pressure from fluid pressure. The service brake can be an electric service brake such as a brake-by-wire configured to electrically generate W/C pressure.
[0043] The brake ECU 19 is configured by a known microcomputer including a CPU, a ROM, a RAM, an I/O, and the like. The engine ECU 10 executes various calculation and processing according to programs stored in the ROM and the like to control braking force (brake torque) and control braking force generated at the respective wheels FL to RR. Specifically, the brake ECU 19 receives detection signals from wheel speed sensors 20 FL to 20 RR provided at the wheels FL to RR, respectively, to calculate various physical quantities such as wheel speed and vehicle body speed, and receives a detection signal from a brake switch 21 to execute brake control in accordance with calculation results of the physical quantities and a brake operation state. The brake ECU 19 receives a detection signal from an M/C pressure sensor 22 and detects M/C pressure.
[0044] The brake ECU 19 also executes off-road support control (hereinafter, referred to as OSC) as vehicle control on off roads in accordance with braking force control. Specifically, the brake ECU 19 receives a detection signal from an OSC switch 23 operated by a driver requesting OSC and detection signals from suspension stroke sensors 24 FL to 24 RR configured to detect a suspension stroke indicative of a change in vehicle load and from an acceleration sensor 25 configured to detect longitudinal acceleration, and executes OSC in accordance with these detection signals. The OSC switch 23 is considered to be pressed basically for off road travel. Similar control is executed also in a case where the OSC switch 23 is pressed on a steeply sloping road or the like. According to FIG. 1 , detection signals from the M/C pressure sensor 22 and the acceleration sensor 25 are inputted to the brake ECU 19 through the brake actuator 15 . The brake ECU 19 can be alternatively configured to receive detection signals directly from the respective sensors.
[0045] The braking and driving systems of the vehicle, to which the vehicle control device according to the present embodiment is applied, are configured as described above. Subsequently described is operation of the vehicle control device configured as described above. The vehicle control device according to the present embodiment also executes regular engine control and brake control as vehicle control similar to those of the conventional technique. Accordingly, described herein is OSC relevant to the characteristics of the present invention along with TRC executed in cooperation with OSC.
[0046] OSC is executed when a driver presses the OSC switch 23 to request execution of OSC. The vehicle control device according to the present embodiment executes, as OSC, control satisfying conditions that (1) the vehicle starts or is accelerated in a case where a driver intends to run the vehicle by pressing the accelerator pedal 11 , (2) operability is facilitated by executing vehicle control with a single pedal operation action, and (3) the ground-covering properties are improved by executing TRC according to a vehicle travel state, and the like.
[0047] The control satisfying the condition (1) is executed to achieve travel according to a driver's intention even if the driver is not used to off road travel or the like, by starting or accelerating the vehicle in accordance with the driver's intention. For example, driving force is increased in accordance with road-surface resistance or increase in driver's operation amount of the accelerator pedal 11 .
[0048] Driving force is increased in accordance with road-surface resistance under the following condition, for example.
[0049] Vehicle travel is disturbed when the vehicle ascends on a steeply sloping road surface or the like. Driving force is thus increased in accordance with a surface gradient. Driving force is increased in accordance with a surface gradient in this manner, so that driving force corresponding to the surface gradient is increased even when the vehicle ascends on a steeply sloping road surface. The vehicle can thus smoothly ascend the sloping road when driving force is increased by driver's accelerator operation. A surface gradient can be calculated in accordance with a known technique, from a gravity acceleration component included in a detection signal from the acceleration sensor 25 . An amount of increase in driving force according to such a surface gradient will be referred to as sloping road grade driving force SLOPE in the following description.
[0050] TRC is executed to a wheel having an acceleration slip, by applying braking force to a control target wheel so as to inhibit the acceleration slip. Driving force corresponding to the braking force is added to driving force of a different wheel so as to increase driving force. An amount of decrease in driving force due to acceleration slip inhibitory control can thus be added to driving force of the different wheel so as to inhibit decrease in total driving force. Such an amount of increase in driving force to be added to driving force of a different wheel in correspondence with an amount of decrease in driving force of a control target wheel due to TRC will be referred to as slip corresponding driving force VWSLIP in the following description.
[0051] In this case, driving force can be increased in correspondence with surface friction force decreased by a slip (hereinafter, referred to as surface μ). In a case where an acceleration slip is generated, the acceleration slip is inhibited by generating braking force at an inhibitory control target wheel by TRC. The acceleration slip is not entirely cancelled but is generated to some extent. Driving force is thus increased in correspondence with the surface μ decreased by the slip. Driving force corresponding to the surface μ decreased by the slip can thus be added to driving force of a different wheel so as to inhibit decrease in total driving force.
[0052] In a case where a wheel is decreased in road surface grounding load by vehicle load shift between wheels, driving force of the different wheel can be similarly increased by an amount of decrease in driving force due to the decrease in road surface grounding load. Driving force decreased by the decrease in road surface grounding load can thus be added to driving force of the different wheel so as to inhibit decrease in total driving force. A change in grounding load due to load shift between wheels can be detected in accordance with detection signals from the suspension stroke sensors 24 FL to 24 RR. Out of increase in driving force corresponding to an amount of decrease in braking force due to an acceleration slip, increase in driving force corresponding to the surface μ decreased by a slip, and increase in driving force corresponding to a change in grounding load, either one can be selectively executed or some can be simultaneously executed in combination.
[0053] It is possible to further increase driving force in accordance with feedback of vehicle body speed. Specifically, target speed corresponding to engine output according to an operation amount of the accelerator pedal 11 is calculated as engine target threshold speed. Feedback control is executed such that actual vehicle body speed approaches the target speed in accordance with a deviation from the vehicle body speed. Feedback control has only to be in a conventional ordinary form, and examples thereof include PID control. An amount of increase in driving force according to the feedback of vehicle body speed will be referred to as feedback driving force V 0 FB in the following description.
[0054] Driving force is increased in accordance with increase in driver's operation amount of the accelerator pedal 11 under the following condition or the like.
[0055] Engine target threshold speed is initially set in accordance with the operation amount of the accelerator pedal 11 . The engine target threshold speed is increased as the operation amount of the accelerator pedal 11 is larger. It is not preferred to increase target speed beyond necessity during off road travel with OSC being executed. The engine target threshold speed according to the operation amount of the accelerator pedal 11 is set preferably within a range not more than predetermined speed (e.g. 6 km/h).
[0056] Driving force is alternatively increased in accordance with an accelerator open degree. Specifically, the degree of a driver's acceleration request is considered to be higher as the accelerator open degree is larger. Feedforward control is thus executed to increase an amount of increase in driving force as the accelerator open degree is larger. Driving force can be generated in more accordance with the driver's acceleration request. Such increase in driving force according to an accelerator open degree will be referred to as accelerator corresponding driving force ACC_FORCE in the following description.
[0057] In a case where vehicle body speed approaches the engine target threshold speed even with a high accelerator open degree, the vehicle travels at desired speed and increase in driving force is considered to be unnecessary. The accelerator corresponding driving force ACC_FORCE is thus preferably decreased in accordance with increase in vehicle body speed.
[0058] OSC is continuously executed even when the vehicle is stopped in accordance with operation to the brake pedal 13 . In this case, driving force is reduced in correspondence with an amount of braking force according to an operation amount of the brake pedal 13 . The sloping road grade driving force SLOPE is to be generated in a case where the vehicle stops on a sloping road. If the brake pedal 13 is pressed and braking force is generated, the vehicle does not shift downward even when driving force is decreased in correspondence with the amount of the braking force. In a case where braking force is generated in accordance with operation to the brake pedal 13 while the vehicle stops, driving force is decreased in correspondence with the amount of the braking force so as to achieve improvement in fuel economy. An amount of decrease in driving force according to operation to the brake pedal 13 will be referred to as brake corresponding driving force FOOTBRAKE in the following description.
[0059] The control satisfying the condition (2) is executed to prevent a difference between a driver's intention and acceleration or deceleration of a vehicle as in such a case where the vehicle travels excessively after running over an obstacle or a case where the vehicle accelerates on a steeply descending road. Because the vehicle travel state changes constantly during off road travel or the like, a driver is unlikely to appropriately execute accelerator operation or brake operation. The vehicle does not behave in accordance with a driver's intention if the driver drives the vehicle in a manner of driving on a flat road. The control satisfying the condition (2) is thus executed to control the vehicle so as to travel at speed intended by the driver by simpler operation. For example, the vehicle is made to decelerate if the driver weakens accelerator operation, and the vehicle is made to decelerate if the driver performs brake operation at least slightly.
[0060] The vehicle is decelerated when the vehicle suddenly accelerates with no change in accelerator operation or when accelerator operation is weakened, so as to achieve quick deceleration without switching from the accelerator pedal 11 to the brake pedal 13 .
[0061] The vehicle occasionally accelerates suddenly with no change in accelerator operation in such a case where the vehicle has run over an obstacle or a case where the road changes to a steeply descending road. In order to cope with such a case, engine target threshold speed according to the accelerator open degree is calculated and brake control is executed when the vehicle accelerates suddenly, so as to inhibit sudden acceleration and increase speed gradually. Specifically, the vehicle target speed is provided with an upper limit value guard so as to prevent sudden acceleration of the vehicle against a driver's intention. The vehicle target speed to be guarded by the upper limit value is set as OSC brake target threshold speed separately from the engine target threshold speed, so that braking force is generated through brake control when the vehicle body speed reaches the OSC brake target threshold speed.
[0062] When accelerator operation is weakened, a driver is considered to intend to decelerate the vehicle. Target deceleration is set in accordance with an accelerator restoring amount and the OSC brake target threshold speed is set in consideration of the target deceleration. In a case where accelerator restoring operation is performed to suddenly restore the accelerator pedal 11 , the target deceleration is set to a large value so as to provide a predetermined time period T with the large target deceleration (hereinafter, this period is referred to as a large deceleration period T). This large deceleration period T can be fixed to a constant time period, or can be set to be long in accordance with speed of the accelerator restoring operation or the like. It is thus possible to achieve large deceleration corresponding to the accelerator restoring operation. The large deceleration period T is set in a case where accelerator operation is cancelled and restoring operation is performed in the present embodiment. The large deceleration period T can be alternatively set to have larger deceleration in a case where accelerator restoring operation is performed suddenly, e.g. when an accelerator restoring amount per unit time period is larger than a threshold, in comparison to another case where the accelerator restoring amount per unit time period is smaller than the threshold.
[0063] The target deceleration is set in accordance with an IDLE ON time period in which accelerator operation is stopped into an OFF state and engine output comes into an idle state (hereinafter, referred to as IDLE ON), and the OSC brake target threshold speed is set in consideration of the target deceleration. The large deceleration period T is provided in a case where sudden accelerator restoring operation is performed to come into an IDLE ON state, for example. After the IDLE ON time period reaches the large deceleration period T, regular target deceleration is set to be smaller than the target deceleration set upon sudden accelerator restoring operation. The OSC brake target threshold speed is set in accordance with the target deceleration thus set.
[0064] In contrast, the vehicle is made to decelerate also in a case where brake operation is performed at least slightly, or a case where a driver presses the brake pedal 13 at least slightly. Vehicle body speed is decelerated slowly if neither accelerator operation nor brake operation is performed. In contrast, a driver is considered to feel insufficient deceleration if brake operation is performed at least slightly. If brake operation is performed at least slightly, the target deceleration is set to be accordingly larger than a case of the IDLE ON state and the OSC brake target threshold speed is set in consideration of the target deceleration thus set.
[0065] The target deceleration is increased in accordance with brake operation by a driver. In a case where vehicle deceleration becomes less than the target deceleration due to the fact that a driver strongly presses the brake pedal 13 or a descending road is suddenly decreased in surface gradient, the target deceleration is set to follow the vehicle body speed and the OSC brake target threshold speed is decreased to the vehicle body speed. It is thus possible to prevent a large difference between the vehicle body speed and the OSC brake target threshold speed when the vehicle deceleration becomes lower than the target deceleration.
[0066] The control satisfying the condition (3) is performed to correct a brake control amount in accordance with the vehicle travel state during off road travel or the like. The brake control amount and target speed as a TRC control threshold are switched in accordance with the vehicle body speed and a monitoring time period. The TRC target speed is a threshold for determination of braking force application for acceleration slip inhibition, and is set to a value obtained by adding slip speed to the vehicle body speed. If wheel speed of a driving wheel exceeds the target speed, braking force is applied to the driving wheel to inhibit the acceleration slip. The target speed of TRC will be hereinafter referred to as TRC brake target threshold speed.
[0067] For example, a driver tends to excessively press the accelerator during off road travel or the like, and a slip may be generated at a wheel and TRC may be executed. In this case, there are a travel state in which the ground-covering properties are improved by transmitting driving force from a slipping wheel to a different wheel and a travel state in which the slip stops and braking force is excessively applied to decrease vehicle body speed V 0 and deteriorate the ground-covering properties. The former is regarded as a travel state with a lower degree of the stall prevention request and the latter is regarded as a travel state with a higher degree of the stall prevention request. Accordingly, the brake control amount is corrected in accordance with the degree of the stall prevention request so as to be matched to a travel state.
[0068] Specifically, a vehicle travelling at low vehicle body speed often travels on a road surface of high travel difficulty with a small degree of the stall prevention request. In this case, stronger wheel slip inhibitory control by brake control is thus executed to exert a limited-slip differential (LSD (differential gear unit)) effect, improve the ground-covering properties, and generate more deceleration, so that safety can be enhanced. In other words, the TRC brake target threshold speed is switched in accordance with the vehicle body speed. If the vehicle body speed increases, it is considered that the vehicle has left a place of high travel difficulty and the degree of the stall prevention request is high. Switching is thus performed to reduce the brake control amount, so as to prevent failing to reach speed requested by a driver due to generation of large braking force under a condition where the driver intends to drive faster. Such control according to vehicle body speed is achieved by setting, in accordance with the vehicle body speed, a first brake coefficient TB 1 referred to for setting of a TRCbrake correction coefficient TB as a correction coefficient to be multiplied to the brake control amount of TRC and a first threshold TV 1 referred to for setting of slip speed TV, as to be described later.
[0069] If the brake control amount and the TRC brake target threshold speed are switched frequently, variation in brake control amount or the like is large due to the switching. A predetermined monitoring time period is thus set to reduce the variation or the like. The brake control amount and the TRC brake target threshold speed are switched if a switching condition is satisfied during the monitoring time period. For example, the switching is performed if the switching condition is satisfied during the predetermined monitoring time period set to one second.
[0070] The brake control amount and the TRC brake target threshold speed are alternatively switched in accordance with the accelerator open degree. Specifically, the brake control amount is increased because driving force is large at the beginning of pressing the accelerator pedal 11 . If the accelerator pedal 11 is pressed continuously, a slip amount due to acceleration increases and braking force increases excessively. The brake control amount is thus made smaller than that at the beginning of the pressing operation. Such control according to the accelerator open degree is achieved by setting, in accordance with the accelerator open degree, a TRC brake coefficient correction value TBK referred to for setting of the TRCbrake correction coefficient TB and a TRC threshold correction value TVK referred to for setting of the slip speed TV.
[0071] The brake control amount and the TRC brake target threshold speed are alternatively switched in accordance with road-surface resistance. With high road-surface resistance, the vehicle tends to stall when braking force is generated by brake control. The brake control amount is thus made smaller than that for a road surface with small road-surface resistance. The road-surface resistance is high in a case where the vehicle is travelling on a desert road, a muddy road, or the like. In this case, the vehicle tends to stall if braking force is generated. Such control according to road-surface resistance is achieved by setting, in accordance with the road-surface resistance, a second brake coefficient TB 2 referred to for setting of the TRCbrake correction coefficient TB and a TRC threshold TV 2 referred to for setting of the slip speed TV.
[0072] As described above, the control satisfying the conditions (1) to (3) is executed upon execution of OSC. TRC and the like are executed regularly even in a case where OSC is not executed. Various values relevant to TRC are set depending on whether or not OSC is executed. OSC and TRC are executed in this manner.
[0073] Subsequently described in detail is OSC executed as described above. FIGS. 2A and 2B and 2C are flowcharts of the entire OSC including the TRC. The brake ECU 19 executes the processing in the flowcharts in these figures at every predetermined control cycle. OSC will be described in detail below with reference to these figures.
[0074] Various input processing is executed initially in step 100 . Specifically, the brake ECU 19 receives detection signals from the respective wheel speed sensors 20 FL to 20 RR and a detection signal from the acceleration sensor 25 , and calculates wheel speed VW** of each of the wheels FL to RR and vehicle longitudinal acceleration Gx. A suffix ** in the wheel speed VW** indicates any one of the signs FL to RR, and the sign VW** totally indicates wheel speed of a corresponding one of the wheels FL to RR. The suffix ** will similarly indicate any one of the signs FL to RR in the following description.
[0075] The brake ECU 19 receives a detection signal from the M/C pressure sensor 22 and detects M/C pressure, as well as receives detection signals from the suspension stroke sensors 24 FL to 24 RR and detects a stroke of the suspension, so as to detect a change in load of the vehicle. The brake ECU 19 also receives an engine open degree, driving force, and a gear position of the auxiliary transmission 2 b , particularly whether a position H 4 or a position L 4 , from the engine ECU 10 and the like through the onboard LAN 12 . The brake ECU 19 further receives a detection signal from the OSC switch 23 and detects whether or not a driver is requesting OSC.
[0076] The flow then proceeds to step 105 , and the brake ECU 19 determines whether or not a condition for execution of OSC is satisfied, particularly, whether or not the gear position of the auxiliary transmission 2 b is at the position L 4 to set a gear ratio in low gear for an off road or the like and whether or not the OSC switch 23 is ON. If positive determination is made, the condition for execution of OSC is satisfied, so that the flow proceeds to step 110 and the brake ECU 19 sets a flag indicating OSC control permission. In contrast, if negative determination is made, the condition for execution of OSC is not satisfied, so that the flow proceeds to step 115 and the brake ECU 19 sets a flag indicating OSC control prohibition.
[0077] The flow subsequently proceeds to step 120 and the brake ECU 19 calculates vehicle body speed V 0 from each wheel speed VW** and calculates a slip ratio Sratio** expressed as a deviation between each wheel speed VW** and the vehicle body speed V 0 (=(VW**−V 0 )/V 0 ). The flow further proceeds to step 125 and the brake ECU 19 differentiates the vehicle body speed V 0 by time to calculate vehicle body acceleration V 0 ′. The flow then proceeds to step 130 and the brake ECU 19 calculates the sloping road grade driving force SLOPE. A difference between the vehicle body acceleration V 0 ′ and the vehicle longitudinal acceleration Gx calculated from the detection signal of the acceleration sensor 25 in step 100 corresponds to the gravity acceleration component. The brake ECU 19 calculates a surface gradient θ in accordance with an operational expression of surface gradient θ=sin−1{(Gx−V 0 ′)/9.8}. In accordance with the calculation result, the brake ECU 19 calculates the sloping road grade driving force SLOPE required for preventing downward shift of the vehicle at the surface gradient θ.
[0078] The flow then proceeds to step 135 and the brake ECU 19 calculates the brake corresponding driving force FOOTBRAKE. The M/C pressure calculated in accordance with the M/C pressure sensor 22 in step 100 corresponds to the operation amount of the brake pedal 13 . The brake ECU 19 thus calculates braking force due to operation of the brake pedal 13 from the M/C pressure. The braking force thus calculated is regarded as the brake corresponding driving force FOOTBRAKE.
[0079] The flow then proceeds to step 140 and the brake ECU 19 determines whether or not OSC control prohibition is set. If negative determination is made, the flow proceeds to step 145 and the brake ECU 19 calculates the engine target threshold speed corresponding to engine output according to the accelerator operation amount of OSC. As described above, the engine target threshold speed has a value of a target speed for execution of feedback control. The engine target threshold speed is calculated from an accelerator opening rate (%) as a rate of an accelerator open degree.
[0080] FIG. 3 is a chart illustrating a method of setting the engine target threshold speed. Temporary engine target threshold speed is denoted by TVEtmp 1 whereas actually set engine target threshold speed is denoted by TVE. FIG. 4 is a map of the relation between the accelerator opening rate and the temporary engine target threshold speed TVEtmp 1 .
[0081] As depicted in FIG. 4 , the engine target threshold speed TVEtmp 1 corresponding to the accelerator opening rate is obtained. The engine target threshold speed TVEtmp 1 has a larger value as the accelerator opening rate increases so as to be in proportion to the accelerator opening rate. During off road travel or the like with OSC being executed, the vehicle possibly travels excessively when running over a projecting road with driving force generated in accordance with a large operation amount of the accelerator pedal 11 . The temporary engine target threshold speed TVEtmp 1 is thus preferred to be suppressed to a value of a certain degree. The temporary engine target threshold speed TVEtmp 1 is thus provided with an upper limit value in the present embodiment so as to be limited to the upper limit value if the accelerator opening rate exceeds a predetermined threshold (40% in FIG. 4 ).
[0082] As depicted in FIG. 3 , the engine target threshold speed is set to 0 km/h in a braking state. If the temporary engine target threshold speed TVEtmp 1 is larger than the engine target threshold speed TVE set at the previous control cycle, the engine target threshold speed TVE at the current control cycle is set to a value obtained by adding constant acceleration (0.03 G in FIG. 3 ) to the engine target threshold speed TVE set at the previous control cycle. If the temporary engine target threshold speed TVEtmp 1 is not larger than the engine target threshold speed TVE set in the braking state or at the previous control cycle, the temporary engine target threshold speed TVEtmp 1 is set as engine target threshold speed TVE at the current control cycle. Priority levels are provided in the order of 1 to 3. If the conditions are matched, the engine target threshold speed TVE at the current control cycle is set in the order of the priority levels. The engine target threshold speed TVE at the current control cycle is set in this manner.
[0083] The flow subsequently proceeds to step 150 and the brake ECU 19 calculates accelerator operation amount requested driving force. The accelerator operation amount requested driving force is driving force required for execution of the control satisfying the condition (1), and has a value obtained from the sloping road grade driving force SLOPE, the slip corresponding driving force VWSLIP, the feedback driving force V 0 FB, the accelerator corresponding driving force ACC_FORCE, and the brake corresponding driving force FOOTBRAKE. The accelerator operation amount requested driving force is calculated as an engine requested value in this case.
[0084] FIG. 5 is a flowchart of detailed processing of calculating the accelerator operation amount requested driving force.
[0085] Initially in step 200 , temporary requested driving force ACC_REQ is obtained from the accelerator opening rate (%) as a rate of an accelerator open degree. The temporary requested driving force ACC_REQ is driving force corresponding to the accelerator operation amount but has a value in no consideration of increase in driving force and the like due to a surface gradient, a slip, and the like described above. The relation between the accelerator opening rate and the temporary requested driving force ACC_REQ is preliminarily obtained through simulation or the like, and the temporary requested driving force ACC_REQ is increased as the accelerator opening rate increases, for example. During off road travel or the like with OSC being executed, the vehicle possibly travels excessively when running over a projecting road with driving force generated in accordance with a large operation amount of the accelerator pedal 11 . The temporary requested driving force ACC_REQ is thus preferred to be suppressed to a value of a certain degree. The temporary requested driving force ACC_REQ is thus provided with an upper limit value in the present embodiment so as to be limited to the upper limit value if the accelerator opening rate exceeds a predetermined threshold (40% in FIG. 5 ).
[0086] The flow subsequently proceeds to step 205 and a requested driving correction coefficient ACC_RATIO is obtained. The requested driving correction coefficient ACC_RATIO is a coefficient for correction of the accelerator corresponding driving force ACC_FORCE in accordance with the vehicle body speed V 0 . The requested driving force is increased as the operation amount of the accelerator pedal 11 is larger. It is not preferred to increase the requested driving force beyond necessity during off road travel with OSC being executed. Assuming that the requested driving correction coefficient ACC_RATIO is 1 while the vehicle stops (the vehicle body speed V 0 =0 km/h), the requested driving correction coefficient ACC_RATIO is decreased linearly until the vehicle body speed V 0 reaches predetermined speed (e.g. 6 km/h). In other words, it is determined that the vehicle has run over an obstacle for travel or the like once the vehicle starts travelling, and the requested driving correction coefficient ACC_RATIO is decreased so as to decrease the accelerator corresponding driving force ACC_FORCE. The requested driving correction coefficient ACC_RATIO is set to 0 if the vehicle body speed V 0 exceeds predetermined speed, in order to inhibit the vehicle body speed V 0 from exceeding the predetermined speed.
[0087] The flow then proceeds to step 210 , and the accelerator corresponding driving force ACC_FORCE is calculated by multiplying the temporary requested driving force ACC_REQ calculated in step 200 and the requested driving correction coefficient ACC_RATIO.
[0088] The flow subsequently proceeds to step 215 and an engine requested value ENG_REQ corresponding to the accelerator operation amount requested driving force is calculated. Specifically, the engine requested value ENG_REQ is calculated by adding the sloping road grade driving force SLOPE, the slip corresponding driving force VWSLIP, the feedback driving force V 0 FB, and the accelerator corresponding driving force ACC_FORCE and subtracting the brake corresponding driving force FOOTBRAKE from the added result.
[0089] For example, the sloping road grade driving force SLOPE is set to the value obtained in step 130 in FIGS. 2A and 2C .
[0090] Because TRC is executed in accordance with the slip ratio Sratio** calculated in step 120 in FIGS. 2A and 2C , as to the slip corresponding driving force VWSLIP, braking force for inhibition of an acceleration slip calculated in TRC is inputted to be referred to as an amount of decrease in driving force of a control target wheel. In a case where the vehicle does not execute TRC, driving force corresponding to the surface μ decreased due to a slip is obtained simply from the slip ratio, as the slip corresponding driving force VWSLIP. Grounding loads of the respective wheels can be obtained from detection signals of the suspension stroke sensors 24 FL to 24 RR inputted in step 100 in FIGS. 2A and 2C , and an amount of decrease in driving force corresponding to decrease in grounding load due to load shift between wheels can be calculated to be referred to as the slip corresponding driving force VWSLIP. Specifically, the slip corresponding driving force VWSLIP can be obtained by calculating driving force transmittable from each of the wheels to a road surface from the grounding load of the corresponding wheel, and adding, if driving force applied to any one of the wheels exceeds the transmittable driving force, the exceeding amount of the driving force.
[0091] Referred to as the feedback driving force V 0 FB is an amount of increase in driving force calculated by feedback control so as to cause the vehicle body speed V 0 calculated in steps 120 and 145 in FIGS. 2A and 2C to approach the engine target threshold speed. Referred to as the accelerator corresponding driving force ACC_FORCE is the value obtained in step 210 . Referred to as the brake corresponding driving force FOOTBRAKE is the value calculated in step 135 in FIGS. 2A and 2C . Calculated in this manner is the engine requested value ENG_REQ corresponding to the accelerator operation amount requested driving force.
[0092] This engine requested value ENG_REQ is transmitted to the engine ECU 10 , and engine output is controlled such that the engine requested value ENG_REQ is reflected only in a case where the engine requested value ENG_REQ exceeds driving force set in engine control to generate driving force corresponding to the engine requested value ENG_REQ. It is thus possible to generate driving force required for execution of the control satisfying the condition (1).
[0093] The flow then proceeds to step 155 for processing of calculating the OSC brake target threshold speed. As described in the control satisfying the condition (2), the OSC brake target threshold speed is a threshold for generation of braking force due to brake control in a case where the vehicle body speed increases. FIG. 6 is a flowchart of processing of calculating the OSC brake target threshold speed. The processing of calculating the OSC brake target threshold speed will be described in detail with reference to this figure.
[0094] Initially calculated in step 300 is first brake target threshold speed TVBtmp 1 to be set temporarily. Set in this case as the first brake target threshold speed TVBtmp 1 is a smaller one of OSC brake target threshold speed TVB set at the previous control cycle and the vehicle body speed V 0 at the current control cycle. Considered in this case are the OSC brake target threshold speed TVB set at the previous control cycle as well as the vehicle body speed V 0 . Accordingly, as to be described later, the brake target threshold speed TVB can decrease in conformity with the vehicle body speed V 0 in a case where the vehicle body speed V 0 is suddenly decreased by brake operation to become lower than the brake target threshold speed TVB.
[0095] The flow then proceeds to step 305 and second brake target threshold speed TVBtmp 2 is set temporarily. FIG. 7 is a chart illustrating a method of setting the second brake target threshold speed TVBtmp 2 .
[0096] Various conditions are set as in FIG. 7 , and the second brake target threshold speed TVBtmp 2 is set in accordance with the various conditions. Similarly to the engine target threshold speed TVE, priority levels are provided in the order of 1 to 6. If the conditions are matched, the second brake target threshold speed TVBtmp 2 at the current control cycle is set in the order of the priority levels.
[0097] Initially, in a state where backup control is executed and the vehicle body speed is less than 10 km/h, the second brake target threshold speed TVBtmp 2 is set to a value obtained by increasing the brake target threshold speed TVB at the previous control cycle by first acceleration (0.025 G in this case). Backup control is executed in a case where OSC is cancelled in view of fail-safe due to generation of some trouble or a case where the OSC switch 23 is OFF. The second brake target threshold speed TVBtmp 2 is set in accordance with the vehicle body speed V 0 in this case. In a state where the vehicle body speed V 0 is not less than 10 km/h, the second brake target threshold speed TVBtmp 2 has a value obtained by increasing the brake target threshold speed TVB at the previous control cycle by second acceleration (0.05 G in this case) larger than the first acceleration.
[0098] If the accelerator operation is performed, accelerator acceleration ACCEL_G according to the accelerator opening rate is calculated, and the brake target threshold speed TVB is calculated by adding the accelerator acceleration ACCEL_G and the previous brake target threshold speed TVB (TVB+ACCEL_G). The accelerator acceleration ACCEL_G is calculated in accordance with the relation between the accelerator opening rate (%) and the accelerator acceleration ACCEL_G indicated in FIG. 8 .
[0099] Specifically, a map indicating that the accelerator acceleration ACCEL_G increases as the accelerator opening rate is larger is obtained preliminarily through simulation or the like, and the accelerator acceleration ACCEL_G corresponding to the accelerator opening rate is calculated with reference to the map. During off road travel or the like with OSC being executed, the vehicle possibly travels excessively when running over a projecting road with driving force generated in accordance with a large operation amount of the accelerator pedal 11 . The accelerator acceleration ACCEL_G is thus preferred to be suppressed to a value of a certain degree. The accelerator acceleration ACCEL_G is thus provided with an upper limit value in the present embodiment so as to be limited to the upper limit value if the accelerator opening rate exceeds a predetermined threshold (45% in FIG. 8 ).
[0100] The second brake target threshold speed TVBtmp 2 is set under these conditions with reference to the brake target threshold speed TVB at the previous control cycle with no reference to the first brake target threshold speed TVBtmp 1 . If the vehicle body speed V 0 at the current control cycle is low, the vehicle body speed V 0 is set to the first brake target threshold speed TVBtmp 1 and the second brake target threshold speed TVBtmp 2 is set with reference to the vehicle body speed V 0 . In this case, the amount of feedback is too small and the brake target threshold speed TVB cannot be changed quickly.
[0101] In a case where accelerator operation is cancelled and the vehicle is brought into a braking state, the vehicle is decelerated with relatively large target deceleration (e.g. 0.1 G). Specifically, the second brake target threshold speed TVBtmp 2 is set such that the vehicle is decelerated with predetermined deceleration in accordance with brake operation if applicable.
[0102] Also in a case where the IDLE ON time period is less than the large deceleration period T, the vehicle is decelerated with relatively large target deceleration (e.g. 0.1 G). Specifically, if accelerator restoring operation is performed suddenly, the target deceleration is set to a large value and the target deceleration is set until the large deceleration period T elapses. The second brake target threshold speed TVBtmp 2 is set in accordance with the target deceleration.
[0103] If none of the above conditions is satisfied, the second brake target threshold speed TVBtmp 2 is set such that the vehicle is decelerated with relatively small target deceleration (e.g. 0.025 G). This applies to a state where neither IDLE ON operation nor brake operation is performed and the large deceleration period T has elapsed. Preferably, the large deceleration period T can be made variable in accordance with accelerator close grade speed corresponding to the accelerator restoring amount per unit time period, such that the large deceleration period T is made longer as the accelerator close grade speed is larger in accordance with the relation between the accelerator close grade speed and the large deceleration period T as indicated in FIG. 9 or the like. The large deceleration period T can thus be set to be long in the case where the accelerator restoring amount is large.
[0104] The second brake target threshold speed TVBtmp 2 is set in this manner. The flow subsequently proceeds to step 310 and third brake target threshold speed TVBtmp 3 is set temporarily. The third brake target threshold speed TVBtmp 3 is set by selecting a smaller one of the second brake target threshold speed TVBtmp 2 set in step 305 and a value obtained by adding a speed upper limit value ACCEL_UP calculated from the accelerator operation amount to the vehicle body speed V 0 at the current control cycle. As described above, because the second brake target threshold speed TVBtmp 2 is set with reference to the first brake target threshold speed TVBtmp 1 or the brake target threshold speed TVB at the previous control cycle, the second brake target threshold speed TVBtmp 2 is occasionally set to a value largely different from a value estimated in consideration of the vehicle body speed V 0 and the accelerator operation amount. Accordingly, a value obtained by adding the speed upper limit value ACCEL_UP to the vehicle body speed V 0 is set as an upper limit value, and the third brake target threshold speed TVBtmp 3 is set with an upper limit guard. The speed upper limit value ACCEL_UP is calculated in accordance with the relation between the accelerator opening rate (%) and the speed upper limit value ACCEL_UP indicated in FIG. 10 .
[0105] Specifically, a map indicating that the speed upper limit value ACCEL_UP increases as the accelerator opening rate is larger is obtained preliminarily through simulation or the like, and the speed upper limit value ACCEL_UP corresponding to the accelerator opening rate is calculated with reference to the map. The speed upper limit value ACCEL_UP is also provided with an upper limit value in this case so as to be limited to the upper limit value if the accelerator opening rate exceeds a predetermined threshold (60% in FIG. 10 ). Accordingly, if the vehicle body speed V 0 increases in correspondence with accelerator operation, the vehicle body speed V 0 is increased with the upper limit guard of the speed upper limit value ACCEL_UP so as not to exceed its increasing grade.
[0106] The flow subsequently proceeds to step 315 and a larger one of the third brake target threshold speed TVBtmp 3 and predetermined lower limit speed (0.8 km/h in FIG. 6 ) is set as a final value of the brake target threshold speed TVB. The third brake target threshold speed TVBtmp 3 is calculated in accordance with the various conditions described above. The brake target threshold speed TVB is provided with a lower limit value guard so that the vehicle can travel at not less than predetermined lower limit speed even if the third brake target threshold speed TVBtmp 3 is less than the lower limit speed. The brake target threshold speed TVB is set in this manner.
[0107] The flow subsequently proceeds to step 160 and various values are calculated, including the TRC brake target threshold speed and the TRCbrake correction coefficient TB as a correction coefficient to be multiplied to the brake control amount of TRC. The TRC brake target threshold speed has a value obtained by adding the slip speed TV to the vehicle body speed V 0 having a variable value. It is thus assumed in this case that the TRC brake target threshold speed is calculated by setting the slip speed TV.
[0108] Methods of calculating the TRC brake target threshold speed and the TRCbrake correction coefficient TB will now be described with reference to FIGS. 11 to 13 .
[0109] The first brake coefficient TB 1 , the first threshold TV 1 , and the like are initially set with reference to FIG. 11 . FIG. 11 is a chart of the relation among the vehicle body speed V 0 along with various conditions, the first brake coefficient TB 1 , and the first threshold TV 1 . The brake control amount of OSC along with TRC is also corrected in correspondence with the vehicle body speed V 0 . FIG. 11 refers to an OSCbrake correction coefficient CB as a correction coefficient of the brake control amount of OSC.
[0110] As indicated in this figure, the first brake coefficient TB 1 , the first threshold TV 1 , and the OSCbrake correction coefficient CB as the correction coefficient of the brake control amount of OSC are set basically in accordance with the vehicle body speed V 0 . Specifically, the first brake coefficient TB 1 and the OSCbrake correction coefficient CB are decreased and the first threshold TV 1 is increased as the vehicle body speed V 0 increases.
[0111] The vehicle often travels on a road surface of high travel difficulty at the vehicle body speed V 0 of 0 km/h in a state where the vehicle is not in a braking state, in other words, a state where a driver intends to run the vehicle but the vehicle stops. Therefore, the first brake coefficient TB 1 is set to a large value and the first threshold TV 1 is set to a small value in order for stronger wheel slip inhibitory control by brake control. The brake control amount of TRC can be increased by setting the first brake coefficient TB 1 to a large value. The slip speed TV defining the TRC brake target threshold speed is decreased by setting the first threshold TV 1 to a small value. Accordingly, TRC can be executed more easily. The brake control amount of OSC is also set to a large value when the vehicle body speed V 0 is 0 km/h, for stronger wheel slip inhibitory control by brake control.
[0112] If the brake control amount and the TRC brake target threshold speed are switched frequently, variation in brake control amount or the like is large due to the switching. In order to reduce the variation, the first brake coefficient TB 1 , the first threshold TV 1 , and the OSCbrake correction coefficient CB are switched in the case where the above conditions are satisfied for a predetermined monitoring time period (one second in this case).
[0113] The first brake coefficient TB 1 and the OSCbrake correction coefficient CB are decreased and the first threshold TV 1 is increased as the vehicle body speed V 0 increases. Priority levels are provided in the order of 1 to 5 for each of the conditions. If the conditions indicated in FIG. 11 are matched, the first brake coefficient TB 1 , the first threshold TV 1 , and the OSCbrake correction coefficient CB are set in the order of the priority levels.
[0114] The TRC brake coefficient correction value TBK and the TRC threshold correction value TVK are set with reference to FIG. 12 . FIG. 12 is a map of the relation of the TRC brake coefficient correction value TBK and the TRC threshold correction value TVK to the accelerator opening rate (%).
[0115] As indicated in this figure, driving force increases in a case where the accelerator opening rate is small at the beginning of pressing the accelerator pedal 11 or the like. Accordingly, the TRC brake coefficient correction value TBK is increased in order to increase the brake control amount. If the accelerator pedal 11 is pressed continuously and the accelerator opening rate increases, a slip amount due to acceleration increases and braking force increases excessively. The TRC brake coefficient correction value TBK is thus decreased in order to decrease the brake control amount from the amount at the beginning of the pressing operation. As to the TRC threshold correction value TVK, an allowable amount of an acceleration slip is increased as the accelerator opening rate increases, so that braking force due to TRC is unlikely to be generated and the brake control amount is decreased.
[0116] The second brake coefficient TB 2 and the TRC threshold TV 2 are set with reference to FIG. 13 . FIG. 13 is a map of the relation of the second brake coefficient TB 2 and the TRC threshold TV 2 to road-surface resistance.
[0117] As depicted in this figure, the second brake coefficient TB 2 and the TRC threshold TV 2 are made variable in accordance with road-surface resistance. Specifically, the second brake coefficient TB 2 is set to a larger value with smaller road-surface resistance and is set to a smaller value with high road-surface resistance. The second brake coefficient TB 2 is referred to for setting of an upper limit value upon setting the TRCbrake correction coefficient TB serving as a correction coefficient of the brake control amount of TRC. A vehicle tends to stall on a road surface having high road-surface resistance when braking force is generated. The TRCbrake correction coefficient TB is provided with an upper limit value guard by setting an upper limit value according to the road-surface resistance by the second brake coefficient TB 2 so as to inhibit increase in brake control amount of TRC in spite of a road surface state easily causing stall.
[0118] On the other hand, the TRC threshold TV 2 is set to a smaller value with smaller road-surface resistance and is set to a larger value with higher road-surface resistance. The TRC threshold TV 2 is used for setting of a lower limit value upon setting the slip speed TV of TRC. A vehicle tends to stall on a road surface having high road-surface resistance when braking force is generated. The slip speed TV is provided with a lower limit value guard by setting a lower limit value according to the road-surface resistance with reference to the TRC threshold TV 2 so as to inhibit generation of braking force due to TRC in spite of a road surface state easily causing stall.
[0119] In this manner, when the first brake coefficient TB 1 , the first threshold TV 1 , the OSCbrake correction coefficient CB, the TRC brake coefficient correction value TBK, the TRC threshold correction value TVK, the second brake coefficient TB 2 , and the TRC threshold TV 2 are set with reference to FIGS. 11 to 13 , the TRC brake target threshold speed and the TRCbrake correction coefficient TB are calculated from these values.
[0120] The TRC brake target threshold speed is calculated by adding the slip speed TV to the vehicle body speed V 0 at the current control cycle. The slip speed TV is set by selecting a larger one of MAX(TV 1 +TVK, TV 2 ), a value obtained by adding the TRC threshold correction value TVK to the first threshold TV 1 and the TRC threshold TV 2 . The TRC brake target threshold speed is thus set by adding the slip speed TV set by MAX(TV 1 +TVK, TV 2 ) to the vehicle body speed V 0 . In contrast, the TRCbrake correction coefficient TB is set by selecting a smaller one of MIN(TB 1 ×TBK, TB 2 ), a value obtained by multiplying the first brake coefficient TB 1 by the TRC brake coefficient correction value TBK, and the second brake coefficient TB 2 .
[0121] The slip speed TV is basically set as a value obtained by adding the TRC threshold correction value TVK set in accordance with the accelerator opening rate to the first threshold TV 1 set in accordance with the vehicle body speed V 0 . The TRCbrake correction coefficient TB is also basically set as a value obtained by multiplying the first brake coefficient TB 1 set in accordance with the vehicle body speed V 0 by the TRC brake coefficient correction value TBK set in accordance with the accelerator opening rate.
[0122] In the case where the vehicle is travelling on a road surface of high travel difficulty as in the case where the vehicle body speed V 0 is low, stronger wheel slip inhibitory control by brake control is executed to exert the LSD effect, improve the ground-covering properties, and generate more deceleration, so that safety can be enhanced. If the vehicle body speed V 0 increases and the vehicle has left a place of high travel difficulty, switching is performed to reduce the brake control amount, so as to prevent generation of large braking force under a condition where the driver intends to drive faster and to achieve speed requested by the driver.
[0123] The brake control amount can be increased when the accelerator opening rate is large and driving force is increased at the beginning of pressing the accelerator pedal 11 , for example. If the accelerator pedal 11 is pressed continuously and the slip amount due to acceleration increases, the brake control amount can be made smaller than that at the beginning of the pressing operation.
[0124] Because the vehicle tends to stall with high road-surface resistance, the slip speed TV is provided with a lower limit value guard by the TRC threshold TV 2 set in accordance with the degree of road-surface resistance. Accordingly, braking force due to TRC is less likely to be generated if road-surface resistance is high. Similarly, the TRCbrake correction coefficient TB is provided with an upper limit value guard by the second brake coefficient TB 2 set in accordance with the degree of road-surface resistance. Accordingly, increase in brake control amount of TRC is prevented if road-surface resistance is high.
[0125] After the TRC brake target threshold speed and the TRCbrake correction coefficient TB are calculated in this manner, the flow proceeds to step 165 and the TRC brake control amount is calculated. The TRC brake control amount is a brake control amount generated by TRC, and has a value corresponding to braking force generated at a wheel generating an acceleration slip as a control target. In this case, obtained as the TRC brake control amount is ** wheel TRC target fluid pressure TTP 1 ** having a fluid pressure converted value of the W/C pressure of a corresponding one of the W/Cs 16 FL to 16 RR of the control target wheel.
[0126] Specifically, the ** wheel TRC target fluid pressure TTP 1 ** is calculated by multiplying a deviation between the wheel speed VW** and the TRC brake target threshold speed (=vehicle body speed V 0 +slip speed TV) by a predetermined gain set by feedback control. A temporary brake control amount of TRC is thus calculated in accordance with the control satisfying the condition (3), specifically, from the slip speed TV set in consideration of the vehicle body speed V 0 , the accelerator opening rate, and the road-surface resistance.
[0127] The flow then proceeds to step 170 , and the ** wheel TRC target fluid pressure TTP 1 ** calculated in step 165 is multiplied by the TRCbrake correction coefficient TB. The ** wheel TRC target fluid pressure TTP 1 ** is thus corrected in accordance with the control satisfying the condition (3), specifically, by the TRCbrake correction coefficient TB set in consideration of the vehicle body speed V 0 , the accelerator opening rate, and the road-surface resistance, and ** wheel TRC final target fluid pressure TTP 2 ** is calculated as the final brake control amount of TRC.
[0128] The flow then proceeds to step 175 and it is determined whether or not OSC control prohibition is set as in step 140 . If negative determination is made, the flow proceeds to step 180 and an OSC brake control amount is calculated. The OSC brake control amount is a brake control amount generated by OSC, and has a value corresponding to braking force generated at a wheel as a control target. In this case, an OSC target control amount TOB is obtained as a target value of the OSC brake control amount, and ** wheel OSC target fluid pressure TOP 1 ** is then obtained with the OSC target control amount TOB serving as a fluid pressure converted value of the W/C pressure of a corresponding one of the W/Cs 16 FL to 16 RR of the control target wheel.
[0129] Specifically, the OSC target control amount TOB is calculated by multiplying a deviation between the vehicle body speed V 0 and the OSC brake target threshold speed TVB obtained in step 155 by a predetermined gain set by feedback control. The ** wheel OSC target fluid pressure TOP 1 ** is calculated by multiplying the OSC target control amount TOB by a brake fluid pressure conversion coefficient. The OSC target control amount TOB is thus calculated in accordance with the control satisfying the condition (2), specifically, from the OSC brake target threshold speed TVB set in consideration of accelerator operation and brake operation, and the ** wheel OSC target fluid pressure TOP 1 ** is calculated by converting the OSC target control amount TOB to fluid pressure. The ** wheel OSC target fluid pressure TOP 1 ** can be set as the final value corresponding to the target value of the OSC brake control amount. Alternatively, the ** wheel OSC target fluid pressure TOP 1 ** is regarded as a temporary brake control amount of OSC and is corrected in accordance with the vehicle body speed V 0 .
[0130] Specifically, the flow proceeds to step 185 , and the ** wheel OSC target fluid pressure TOP 1 ** is multiplied by the OSCbrake correction coefficient CB set in step 160 so as to correct the ** wheel OSC target fluid pressure TOP 1 ** and calculate ** wheel OSC final target fluid pressure TOP 2 **. In this manner, the final brake control amount of OSC is calculated as a value in consideration of the OSCbrake correction coefficient CB set in accordance with the vehicle body speed V 0 .
[0131] The flow then proceeds to step 190 and the final brake control amount in accordance with OSC and TRC is calculated. Specifically, the ** wheel TRC final target fluid pressure TTP 2 ** as the final brake control amount of TRC and the ** wheel OSC final target fluid pressure TOP 2 ** as the final brake control amount of OSC are added to obtain ** wheel target fluid pressure TP** (=TTP 2 **+TOP 2 **) as the final brake control amount of the control target wheel. When the final brake control amount of the control target wheel is calculated in this manner, the brake fluid pressure of a corresponding one of the W/Cs 16 FL to 16 RR of the control target wheel is set as the ** wheel target fluid pressure TP** by an automatic pressurizing function of the service brake. It is thus possible to generate braking force required for execution of the control satisfying the conditions (2) and (3).
[0132] If OSC control prohibition is set and positive determination is made in step 140 , the flow proceeds to step 195 and regular TRC with no OSC is executed. In this case, the TRC brake target threshold speed is calculated for regular TRC. Because OSC control is prohibited, the TRCbrake correction coefficient TB is set to 1.0 in a substantially uncorrected state and the TRC brake target threshold speed is calculated for regular TRC as to the slip speed TV. The ** wheel OSC final target fluid pressure TOP 2 ** is set to 0 [MPa] and the engine requested value ENG_REQ is set to an unreflected value, such as −10000 [N]. Negative determination is made also in step 175 . In step 190 , the ** wheel target fluid pressure TP** as the final brake control amount in accordance with OSC and TRC is set as the ** wheel TRC final target fluid pressure TTP 2 ** only in consideration of TRC.
[0133] Generated as described above are driving force required for execution of the control satisfying the condition (1) and braking force required for execution of the control satisfying the conditions (2) and (3). FIGS. 14A and 14B and 15A and 15B are timing charts of a case where various processing in the flowcharts in FIGS. 2A and 2B and 2C are executed.
[0134] FIGS. 14A and 14B are a timing chart of a case where a travel surface is a mogul road surface (an uneven surface with projections and recesses). Exemplified in this figure is the state where a road surface changes from an ascending mogul road surface, a flat and horizontal road surface, and then a descending road surface.
[0135] Initially, in a state where the accelerator pedal 11 is not pressed but the brake pedal 13 is pressed at a time point T 0 , the priority level 2 in FIG. 11 is selected. The slip speed TV is set in accordance with the selected priority level, and the TRC brake target threshold speed is set as a value obtained by adding the slip speed TV to the vehicle body speed V 0 (=0). Although the priority level 4 in FIG. 7 is selected, there is provided a lower limit value guard. The OSC brake target threshold speed is set to the lower limit value (e.g. 0.8 km/h indicated in step 315 in FIG. 6 ). If brake operation is cancelled at a time point T 1 and this state lasts for a predetermined time period (e.g. one second), the priority level 1 in FIG. 11 is selected at a time point T 2 and the first threshold TV 1 is decreased accordingly. The slip speed TV is thus decreased.
[0136] If accelerator operation is then performed at a time point T 3 , driving force corresponding to the accelerator operation is generated. If the vehicle body speed V 0 increases, the engine target threshold speed is accordingly set to predetermined speed (e.g. 2 km/h). The TRC brake target threshold speed and the OSC brake target threshold speed are also increased along with the increasing vehicle body speed V 0 . As to the OSC brake target threshold speed, the priority level 3 in FIG. 7 is selected and the accelerator acceleration ACCEL_G corresponding to the accelerator opening rate is added. However, a value obtained by adding the speed upper limit value ACCEL_UP to the vehicle body speed V 0 is set as an upper limit value. If the accelerator acceleration ACCEL_G is large, the OSC brake target threshold speed is set to the upper limit value.
[0137] If the vehicle body speed V 0 falls within the speed range indicated in the priority level 2 in FIG. 11 continuously for a predetermined time period (e.g. one second), the priority level 2 in FIG. 11 is selected at a time point T 4 and the TRC brake target threshold speed is corrected to a large value.
[0138] Subsequently, an acceleration slip is generated at one of the wheels FL to RR immediately after the time point T 4 . In the case where the wheel speed VW** exceeds the TRC brake target threshold speed and the OSC brake target threshold speed, there is set requested braking force for the wheel having the acceleration slip. The requested braking force is required for inhibition of the acceleration slip or prevention of sudden acceleration of the vehicle against a driver's intention. The brake control amount is set in accordance with the requested braking force. This state lasts until the vehicle body speed V 0 becomes lower than the TRC brake target threshold speed and the OSC brake target threshold speed. Such behavior is repeated every time an acceleration slip is generated and the wheel speed VW** exceeds the TRC brake target threshold speed and the OSC brake target threshold speed.
[0139] When the accelerator pedal 11 is further pressed at a time point T 5 , the engine target threshold speed is increased accordingly. Driving force corresponding to the accelerator operation is generated accordingly, as well as the vehicle body speed V 0 increases. The TRC brake target threshold speed and the OSC brake target threshold speed also increase accordingly. In the case where the vehicle body speed V 0 falls within the speed range indicated in the priority level 3 in FIG. 11 continuously for a predetermined time period (e.g. one second), the priority level 3 in FIG. 11 is selected at a time point T 6 and the TRC brake target threshold speed is corrected to a large value. In the case where the vehicle body speed V 0 further increases and falls within the speed range indicated in the priority level 4 in FIG. 11 continuously for a predetermined time period (e.g. one second), the priority level 4 in FIG. 11 is selected at a time point T 7 .
[0140] Even though the vehicle body speed V 0 increases suddenly between the time point T 6 and the time point T 7 , the priority level 3 in FIG. 7 is selected as to increase in OSC brake target threshold speed and the vehicle body speed V 0 increases slowly. The vehicle is thus inhibited from travelling excessively.
[0141] If accelerator operation is subsequently cancelled by sudden accelerator restoring operation at a time point T 8 , the priority level 5 in FIG. 7 is selected and the OSC brake target threshold speed is set to a value allowing relatively large deceleration (e.g. 0.1 G). The vehicle body speed V 0 is thus decreased with relatively large deceleration. If the large deceleration period T elapses at a time point T 9 , the priority level 6 in FIG. 7 is selected and the OSC brake target threshold speed is set to have deceleration smaller than that in the large deceleration period T. The vehicle body speed V 0 is thus decreased with relatively small deceleration.
[0142] If a driver performs brake operation at a time point T 10 in this state and the vehicle body speed V 0 is decreased with relatively large deceleration, the priority level 4 in FIG. 7 is selected again and the OSC brake target threshold speed is set to a value allowing relatively large deceleration (e.g. 0.1 G). A value allowing predetermined deceleration is selected for the first brake target threshold speed TVBtmp 1 in the priority level 4 in FIG. 7 . The first brake target threshold speed TVBtmp 1 is set to a smaller one of the brake target threshold speed TVB at the previous control cycle and the vehicle body speed V 0 . Even when the vehicle body speed V 0 suddenly decreases, the first brake target threshold speed TVBtmp 1 is decreased in conformity with the decrease and the brake target threshold speed TVB is set to a small value. Accordingly, the brake target threshold speed TVB can decrease in conformity with the vehicle body speed V 0 in a case where the vehicle body speed V 0 suddenly decreases to become lower than the brake target threshold speed TVB. The brake target threshold speed TVB is set to a value smaller than the vehicle body speed V 0 , so as to prevent the vehicle from accelerating with the vehicle body speed V 0 increasing toward the brake target threshold speed TVB in spite of brake operation being performed. It is thus possible to reduce the vehicle body speed V 0 with simpler operation as well as prevent acceleration of the vehicle against a driver's intention. The vehicle speed can thus be controlled in accordance with the driver's intention.
[0143] If the priority level 4 in FIG. 11 is continuously selected as to the vehicle body speed V 0 similarly to the period between the time point T 7 and a time point T 11 , the slip speed TV does not change. The TRC brake target threshold speed is thus set to a value obtained by adding the constant slip speed TV to the vehicle body speed V 0 . In the case where the vehicle body speed V 0 thereafter becomes lower than the predetermined speed continuously for a predetermined time period (e.g. one second), the priority level 3 in FIG. 11 is selected at a time point T 12 . The priority level 2 in FIG. 11 is selected at a time point T 13 due to further decrease in vehicle body speed V 0 . The TRC brake target threshold speed is thus corrected to be gradually smaller.
[0144] If gentle accelerator operation is performed at a subsequent time point T 14 and gentle accelerator restoring operation is then performed, the priority level 5 in FIG. 7 is selected and the OSC brake target threshold speed is set to a value allowing relatively large deceleration (e.g. 0.1 G). The vehicle body speed V 0 is thus decreased with relatively large deceleration.
[0145] FIGS. 15A and 15B are a timing chart of a case where the travel surface is a desert road surface. Because such a road surface has high road-surface resistance, the vehicle tends to stall when braking force is generated by brake control.
[0146] Behavior similar to that in FIGS. 14A and 14B are performed initially during the period between the time point T 0 and the time point T 3 . Behavior similar to that in FIGS. 14A and 14B are basically performed also during the period between the time point T 4 and the time point T 6 . If an acceleration slip is generated at one of the wheels FL to RR during the period between the time point T 4 and the time point T 6 as well as at time points Ta, Tb, and Tc indicated after the time point T 6 , the brake control amount is set so as to achieve inhibition of the acceleration slip. Specifically, if the wheel speed VW** exceeds the TRC brake target threshold speed and the OSC brake target threshold speed, there is set requested braking force for the wheel having the acceleration slip. The requested braking force is required for inhibition of the acceleration slip or prevention of sudden acceleration of the vehicle against a driver's intention. The brake control amount is set in accordance with the requested braking force.
[0147] In a state where the vehicle body speed V 0 gradually increases as in this example, the priority level sequentially shifts from 1 to 5 in FIG. 11 in accordance with the vehicle body speed V 0 . The first threshold TV 1 increases gradually and the slip speed TV increases accordingly. There is thus a larger difference between the TRC brake target threshold speed set to a value obtained by adding the slip speed TV to the vehicle body speed V 0 and the body speed V 0 . Along with increase in vehicle body speed V 0 , the ** wheel TRC target fluid pressure TTP 1 ** as the brake control amount upon generation of an acceleration slip (see step 165 in FIG. 2B ) is decreased gradually and requested braking force is decreased.
[0148] In addition, as the priority level shifts sequentially from 1 to 5 in FIG. 11 , the first brake coefficient TB 1 is also decreased gradually. The TRCbrake correction coefficient TB is thus decreased gradually along with increase in vehicle body speed V 0 , and the ** wheel TRC final target fluid pressure TTP 2 ** is further decreased.
[0149] The second brake coefficient TB 2 has a small value in the case where road-surface resistance is high. The TRCbrake correction coefficient TB is provided with an upper limit value guard with a small value so that the ** wheel TRC final target fluid pressure TTP 2 ** has a smaller value. The TRC threshold TV 2 has a large value in the case where travel resistance is high. The slip speed TV is thus provided with a lower limit value guard having a larger value. The ** wheel TRC target fluid pressure TTP 1 ** as the brake control amount upon generation of an acceleration slip can have a small value.
[0150] As described above, the vehicle control device according to the present embodiment executes the control satisfying the conditions (1) to (3). There are generated driving force required for execution of the control satisfying the condition (1) and braking force required for execution of the control satisfying the conditions (2) and (3). When the control satisfying the condition (3) is executed, TRC matched to the vehicle travel state is executed for improvement of the ground-covering properties.
Other Embodiments
[0151] The present invention is not limited to the embodiment described above but can be modified appropriately within the scope of the claims.
[0152] For example, the control satisfying the condition (1) to the control satisfying the condition (3) are all executed in the above embodiment. The vehicle control device can alternatively be configured to execute only the control satisfying the condition (3) or execute the control satisfying the condition (3) along with only one of the control satisfying the condition (1) and the control satisfying the condition (2). The above embodiment merely exemplifies the methods of setting the engine target threshold speed, the OSC brake target threshold speed, and the TRC brake target threshold speed. For example, various parameters and maps referred to for setting of these values can be changed appropriately, or not all of the parameters and the maps may be applied but only part thereof can be applied.
[0153] The above embodiment exemplifies a vehicle equipped with an engine, thus exemplifies engine output as driving force according to accelerator operation and engine target threshold speed as target speed corresponding to the engine output. However, this is merely an exemplary form of outputting driving force according to accelerator operation, and can be replaced with a different form. For example, driving force according to accelerator operation corresponds to electrical output according to accelerator operation in an electric vehicle, and to the sum of electrical output according to accelerator operation and engine output in a hybrid vehicle. The engine target threshold speed is exemplified as target speed corresponding to driving force according to accelerator operation. Driving force target threshold speed can be set as target speed corresponding to driving force according to accelerator operation and can be a target of comparison with the vehicle body speed V 0 .
[0154] According to the above embodiment, whether or not OSC should be executed is determined in accordance with the state of the OSC switch 23 and the gear position of the auxiliary transmission 2 b . Alternatively, a road surface condition can be detected and whether or not OSC should be executed can be determined in accordance with a detection result of the road surface condition. For example, a road surface with large recesses and projections or with high road-surface resistance, or a road surface with a large surface gradient such as that of a steeply sloping road can be determined to have a road surface condition of an off road or the like. In this case, it can be determined that OSC should be executed under the road surface condition, and OSC can be executed automatically.
[0155] Those portions configured to execute various processing described in the above embodiments, such as the respective steps and the like depicted in the figures, correspond to various means according to the present invention. For example, the portion configured to execute the processing in step 160 corresponds to a target speed setting means and a brake control amount correction means.
REFERENCE SIGNS LIST
[0000]
1 : Engine, 2 : Transmission device, 2 a : Transmission, 2 b : Auxiliary transmission, 3 : driving force distribution control actuator, 10 : Engine ECU, 11 : Accelerator pedal, 11 a : Accelerator switch, 12 : LAN, 13 : Brake pedal, 14 : M/C, 15 : Brake actuator, 16 : W/C, 19 : Brake ECU, 20 FL to 20 RR: Wheel speed sensor, 21 : Brake switch, 22 : M/C pressure sensor, 23 : Switch, 23 FL to RR: Suspension stroke sensor, 24 FL to: Suspension stroke sensor, 25 : Acceleration sensor | A vehicle control device corrects the amount of brake control according to the degree of stall prevention requests such that the brake control amount is matched to a travel state. For example, when the vehicle body speed is low, the vehicle body is often traveling a road surface that is difficult to travel, and the degree of stall prevention requests is small. In such cases, the vehicle control device exhibits LSD effects and increases ground-covering properties by executing vehicle wheel slip control based on stronger brake control, while increasing safety properties by better enabling generation of deceleration. Then, as the vehicle body speed increases, because it is conceivable that the vehicle body is leaving a place that is difficult to travel and the degree of stall prevention requests is high, the vehicle control device executes switching such that brake control is lowered. | 1 |
BACKGROUND OF THE INVENTION
1. Field of Invention
This invention pertains to a method and apparatus for braiding three-dimensional re-enforced fabrics, these types of fabrics are gaining popularity as structural members in the aerospace industry and other industries requiring very light yet durable materials. Composites reinforced with 3-D fabrics exhibit greater isotropy and fracture toughness than those made with conventional cloth or fiber lay-ups.
2. Description of the prior art
The term THREE-DIMENSIONAL FABRIC refers to textile assemblies with interlaced yarns extending into all three dimensions, eliminating non-reinforced planes within a structure. Non-reinforced planes are the weakest segments in a composite structure. Structural faults such as cracking and delamination tend to propagate along these non-reinforced planes.
Three-dimensional braiding devices are disclosed in U.S. Pat. Nos. to Bluck (3,426,804); Florentine (4,312,261) and Brown (4,621,560). The devices disclosed therein have several common characteristics:
1. The zone in which the fabric is formed, hereinafter called the braiding zone, is relatively long in the longitudinal direction;
2. No provision is made to compensate for slack yarns in the braiding zone resulting in movement of the braiding blocks from the perimeter to the center of the braiding matrix.
3. No means are provided for beating or compacting yarn interlacings to form the fabric either within or adjacent to the braiding zone.
In addition, Florentine discloses magnetic means for positioning the braiding elements in a pre-selected orientation, which makes the device expensive and complex. Brown discloses a device which merely provides a means for aligning elements in the braiding plane to prevent jamming during weaving.
OBJECTIVES AND SUMMARY OF THE INVENTION
In view of the abovementioned disadvantages of the art, it is an objective of the present invention to provide an apparatus and method which can be used to continuously and automatically braid a fabric with fibers oriented in three dimensions, eliminating any non-reinforced planes within the structure.
A further objective is to provide an apparatus and method which forms a three-dimensional fabric which has a uniform longitudinal structure.
Other objectives and advantages of the invention shall become apparent from the following description. An apparatus constructed in accordance with this invention comprises a plurality of braiding elements arranged in a preselected two-dimensional pattern corresponding to the cross-sectional shape of the desired fabric, to form a floating yarn creel. Preferably each braiding element includes a continuous supply of fiber. At a preselected distance away from the creel there is arranged a former plate formed of a plurality of former elements. The former elements are arranged in a pattern essentially identical to the pattern of the braiding elements however the overall cross-sectional dimensions of the former plate are approximately the same as the dimensions of the desired fabric, and generally smaller than the cross-sectional dimensions of the creel. In a specially preferred embodiment of the invention, the apparatus also includes a plurality of beater combs arranged adjacent to the former plate for beating the yarns in the braiding zone to form the fabric. Means are also provided to move the braiding elements, the forming elements and the beating combs in a synchronized movement.
The fabric is braided as follows. Fibers are paid off from the braiding elements through the forming elements. Movement of the braiding and forming elements along preselected paths/ steps causes the fibers to be braided into the fabric. Preferably, the forming and braiding elements are moved in discrete steps, and after one or more such movements, the beating combs are activated for beating the fabric.
Preferably means are provided in the braiding elements for temporarily storing and tensioning extraneous fiber thereby compensating for fiber slack generated by the movement of the braiding elements.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a plan view of a prior art braiding device;
FIG. 2 shows a side-sectional view of a braiding apparatus constructed in accordance with this invention;
FIG. 3 shows a bottom view of the braiding elements of FIG. 2;
FIG. 4 shows an orthogonal view of a plurality of former plate elements used in the apparatus of FIG. 2;
FIG. 5 shows a side-sectional view of the former plate-beater comb assembly for the apparatus of FIG. 2;
FIG. 5A shows a top view of the floating former plate of FIG. 2; and
FIG. 6 shows an orthogonal view of a braiding element of FIG. 2.
DETAILED DESCRIPTION OF THE INVENTION
It should be understood that in the following description of the invention, directional terms such as above, below and so on are used for illustrative purposes only, and the described apparatus may function in any orientation.
FIG. 1 shows a known structure for braiding three-dimensional fabrics. In this structure, a plurality of braiding elements 10 are disposed in a pattern which defines the cross-sectional shape of the desired fabric. More specifically, the braiding elements in FIG. 1 are arranged to form a rectangular fabric. Obviously, by selecting other patterns for the braiding elements, fabrics of different cross-sectional shapes may be made such as square, I-shaped, T-shaped, C-shaped and so on. The fabric is braided by moving elements 10 along preselected paths, such as path 12. The process may be mechanized by shifting alternatively rows and columns of elements in the X and Y direction shown in FIG. 1. For example, element 10' may be shifted from its position shown in FIG. 1 to the position 10" by first moving column A in the Y direction and then moving row B in the X direction.
Referring now to FIGS. 2-6, an apparatus for braiding a three-dimensional fabric constructed in accordance with this invention is comprised of: a floating yarn creel 20, a former plate 22, a first actuator control device (or first ACD) 24 controlling the operation of creel 20 and a second actuator control device (second ACD) 26 for controlling the operation of former plate 22. Optionally, for oversized fabrics, a second or intermediate former plate 28 may be disposed between the creel 20 and former plate 22 as shown. Preferably, above the floating former plate 22 a beater comb assembly 30 is provided for beating the fabric right after the yarns exit from former plate 22. The beater comb assembly is driven by a beater drive means 32.
Floating yarn creel 20 comprises a frame 34 which holds a plurality of braiding elements 36. The braiding elements are disposed in a pattern which defines the shape of the desired fabric as described above in conjunction with FIG. 1. Preferably, each braiding element 36 holds a reel of fiber 38 which is paid off in a manner described in more detail below.
ACD 24 includes a pair of pusher arms 40 which, when activated, pushes a row of braiding elements 36 in the X direction. When the pusher arms are released, a pair of return arms 42 cooperate to return the elements 36 to their original positions. Preferably, return arms 42 are biased by springs 44, to eliminate the need for other drive means. Similar pusher and return arms are provided to move the braiding elements in the Y direction. Since these members are similar to the arms 40, 42 their description is omitted.
While the braiding elements are shifted in the pattern shown in FIG. 1 they must be kept in alignment with each other to insure that no blockage occurs. This is accomplished in the present invention by providing at the bottom and top of the braiding elements a plurality of contact wheels 46. Each wheel is rotatably mounted on a support surface of the element 36. As elements 36 pass each other, with each element following its assigned path, the wheels 46 of one element contacts a sidewall 50 to space the elements properly. As the braiding elements pass each other, rotation of wheels 46 eliminates friction and interference between adjacent elements.
Former plate 22 comprises a frame 52 which holds a plurality of former elements 54 shown in FIGS. 4 and 5. Elements 54 are disposed in a pattern identical to the pattern of the braiding elements 36. Furthermore each former element 54 corresponds to one of the braiding elements 36. Former elements 54 are moved in paths identical to the paths of the corresponding braiding element 36 by arms 56, 58 activated by second ACD 26. The operation of arms 56 and 58 is identical and synchronized with arms 40 and 42 respectively.
In order to insure that the former elements 54 move easily on their respective paths, these elements are provided with a tongue-and-groove arrangement as follows. Each element 54 has an L-shaped tongue 60 which extends substantially across two adjacent sides of the element. On the opposite sides of the element, there is a corresponding groove 62. The tongues and grooves are arranged and constructed so that as two former elements pass each other they keep their respective positions without interference. This same tongue-and-groove arrangement may also be provided on braiding elements 36.
A top section of each former element is narrowed slightly so that channels 63 are defined between each adjacent former element. Slots 64 are cut through frame 52 in line with channels 63 to define a continuous trough. As shown in FIG. 2, each beater comb assembly includes a comb 66' which terminates in a sloped surface 68. Beater drive 32 moves each of the beater combs 66 in a reciprocating motion thereby moving the combs longitudinally through the troughs described above. Each of the former elements is provided with a vertical through-hole 70 shown in FIG. 4.
The apparatus described above operates as follows. Fibers 72, 72' are paid off continuously from reels 38 and pass upwards through through-holes 70 of former elements 54. First and second ACD's 24 and 26 move the brading elements 36 and 54 in synchronized paths thereby braiding the fibers into the fabric 74. The fabric is completely formed at point 76 and passes through a plate 78 on its way to a take-up device 80. Preferably after all braiding and forming the elements have completed a step in the X direction, the beater combs 66 for the Y direction are introduced into the troughs formed on the top of the former elements and pushed through to beat the yarns upward to the fabric formation point. This process insures that the fabric is formed compactly and evenly. The beater combs 66' for the X-direction are moved similarly after all the elements complete a step in the Y direction. The sloped surface 68 on each comb assist the movement of the yarns and insures that the fibers are not ripped by the combs.
It should be appreciated that while the prior art, the formation zone for the fabric extended from the braiding elements to plate 78, in the present invention, the forming zone extends only above forming plate 22. Furthermore, while the floating yarn creel has relatively large cross-sectional dimensions so that the braiding elements 36 can hold the fiber reels 38, plate 22 is much smaller cross-sectional dimensions.
For relatively large fabrics, as the braiding elements move from the outer periphery of the frame toward its center, the fibers from these elements loosen up and could get entangled between the yarn creel and the former plate. This may occur because, as can be seen from FIG. 2, the fibers 72 are shorter than fibers 72'. In order to take up this slack, braiding elements 36 preferably include a reel 38 mounted on a shaft 82. On top of the element 36 there are two fixed pulleys 84, 86. A block 88 is slidably mounted on shaft 82 and is urged downwards toward reel 38 by a compression spring 90. Mounted on block 88 there are two pulleys 92, 94. A fixed eye 96 is used to take the fiber 72 off reel 38. From eye 96, the fiber passes over fixed pulley 84, down to moving pulley 92, up to fixed pulley 86, down to pully 94 and then out through a hole 97. The fiber 72 is initially pretensioned so that it forces block 88 upwards, away from reel 38. As the movement of element 36 tends to slacken fiber 72, block 88 moves downward to keep fiber 72 straight to the former plate eliminating the chance of entanglement. When block 88 reaches its uppermost position--just below reel 86fiber supply 36 is allowed to rotate, paying off additional yarn to permit continuous fabric formation.
Obviously numerous modifications may be made to the invention without departing from its scope as defined in the appended claims. | A three-dimensional fabric is braided with an apparatus having a floating yarn creel and a floating forming plate, each having movable elements. Fibers are fed from the creel through the forming plate to a forming zone where the fibers are braided by synchronous movements of said movable elements. Beaating combs may also be provided in the forming zone. | 3 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a nonprovisional application of and claims priority from U.S. provisional patent application Ser. No. 62/006,286 filed on Jun. 2, 2014. The foregoing application is incorporated in its entirety herein by reference.
FIELD OF THE INVENTION
The invention is related to systems and methods for evaluating water and waste streams. More particularly, the invention is related to systems and methods for evaluating waste streams to select or size a screen.
BACKGROUND
The wastewater industry has responded to increasingly stringent plant effluent requirements with enhanced plant design and innovative technology. While these new procedures are able to treat higher volume flows for less money, these procedures require significant attention to each stage of the improved processes. It is generally accepted that unique plant designs have established and defined performance requirements in order to meet effluent regulations, but increasing emphasis on influent flow analysis is needed to optimize treatment.
Engineers, operators, and maintenance personnel alike have long since realized there are benefits in removing inorganic and settleable solids as early in the treatment process as possible, but preliminary treatment equipment has conventionally been selected more on requirements of downstream processes than influent characteristics. Specifically, as these processes increase in sophistication and sensitivity, plant design is driven towards finer upstream screening protection without further investigation into the type of solids presented to the plant. Generally, this can result in higher capital outlays, larger headworks structures, and frequently increases disposal of the organic and fecal material the plant is designed to treat.
Just as each plant has its own characteristics that dictate the amount of screening protection it requires, every collection system and the waste flow it receives are unique as well. The design of a collection system, constituents feeding the plant, stormwater infiltration, and variations in flow all have a direct impact on the quantity, size, and consistency of screenings in the influent flow of any given treatment plant. The Water Environment Federation (WEF), in co-operation with American Society of Civil Engineers (ASCE), did a study of the screenings volume relative to flow collected at 39 U.S. wastewater treatment plants. Their results proved that plant screenings are so unique they differ by a factor of 70 times. Even conservative sizing used by most screen manufacturers cannot properly account for fluctuations in screenings of this magnitude when calculations are based on peak flow and opening size alone.
What is needed is a method and system for testing with specialized equipment, which may analyze the solids loading characteristics of an individual plant to be expanded from generalized total suspended solids (“TSS”) or biochemical oxygen demand (“BOD”) ranges to stratification of solid sizes present in the waste stream. What is needed is a method and system for analysis of this data that help identify proper screen openings and capture ratios required by downstream processes while determining the appropriate screen type, size, and operational sequence determined by the unique inputs to the individual plant.
SUMMARY
The present invention advantageously provides a method and system for testing with specialized equipment, which may analyze the solids loading characteristics of an individual plant to be expanded from generalized TSS or BOD ranges to stratification of solid sizes presented in the waste stream. Additionally, the present invention advantageously provides a method and system for analysis of this data that help identify proper screen openings and capture ratios required by downstream processes while determining the appropriate screen type, size and operational sequence determined by the unique inputs to the individual plant.
Having more detailed information about the contents of the waste flow in these applications is critical in properly determining the correct screen type, grid, and size for the application. Some factors affecting fluctuations in the quantity, size, and consistency of screenings in the wastewater entering a municipal wastewater treatment plant are detailed below. The present invention advantageously facilitates collection of the information.
The system of the present invention analyzes multiple characteristics of the waste stream and collected data is evaluated for proper selection of screen type, opening, and size for optimal screenings capture, operation time, and capital outlay. The end result is a properly designed system that effectively protects downstream equipment and saves the customer money throughout the entire plant. The system and methods of the present invention advantageously maximize screening capture, measure existing screen performance, reduced chance of screen failure or headwork flooding, greatly improved hydraulic performance predictions, and quantifies loading in municipal wastewater, pulp and paper, food processing, brewery, pharmaceutical, and other unique waste streams.
The present invention may collect data to be evaluated to give a representation of solids loading at a testing site. The results may be compared with other facilities to determine valuable information for selecting and properly sizing screening equipment. Dual stage screens may be designed for balanced binding, headlosses, and screen size.
Unless otherwise defined, all technical terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described below. All publications, patent applications, patents and other references mentioned herein are incorporated by reference in their entirety. In the case of conflict, the present specification, including definitions will control.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram of screen types, according to an embodiment of the present invention.
FIG. 2 is a chart illustrating flow rates for screen types, according to an embodiment of the present invention.
FIG. 3 is a photographic view of a filtration device usable with the system, according to an embodiment of the present invention.
FIG. 4 is a perspective view of the test system in operation, according to an embodiment of the present invention.
FIG. 5 is a table displaying an illustrative test itinerary, according to an embodiment of the present invention.
FIGS. 6-7 are block diagrams of illustrative test procedures, according to an embodiment of the present invention.
FIG. 8 is a diagram of a slotted screen type, according to an embodiment of the present invention.
FIG. 9 is a diagram of a first perforated screen type, according to an embodiment of the present invention.
FIG. 10 is a diagram of a second perforated screen type, according to an embodiment of the present invention.
FIG. 11 is a diagram of a third perforated screen type, according to an embodiment of the present invention.
FIGS. 12-16 are photographic images illustrating features of various embodiments of the present invention.
DETAILED DESCRIPTION
The present invention is best understood by reference to the detailed drawings and description set forth herein. Embodiments of the invention are discussed below with reference to the drawings; however, those skilled in the art will readily appreciate that the detailed description given herein with respect to these figures is for explanatory purposes as the invention extends beyond these limited embodiments. For example, in light of the teachings of the present invention, those skilled in the art will recognize a multiplicity of alternate and suitable approaches, depending upon the needs of the particular application, to implement the functionality of any given detail described herein beyond the particular implementation choices in the following embodiments described and shown. That is, numerous modifications and variations of the invention may exist that are too numerous to be listed but that all fit within the scope of the invention. Also, singular words should be read as plural and vice versa and masculine as feminine and vice versa, where appropriate, and alternative embodiments do not necessarily imply that the two are mutually exclusive.
The present invention should not be limited to the particular methodology, compounds, materials, manufacturing techniques, uses, and applications, described herein, as these may vary. The terminology used herein is used for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention. As used herein and in the appended claims, the singular forms “a,” “an,” and “the” include the plural reference unless the context clearly dictates otherwise. Thus, for example, a reference to “an element” is a reference to one or more elements and includes equivalents thereof known to those skilled in the art. Similarly, for another example, a reference to “a step” or “a means” may be a reference to one or more steps or means and may include sub-steps and subservient means.
All conjunctions used herein are to be understood in the most inclusive sense possible. Thus, a group of items linked with the conjunction “and” should not be read as requiring that each and every one of those items be present in the grouping, but rather should be read as “and/or” unless expressly stated otherwise. Similarly, a group of items linked with the conjunction “or” should not be read as requiring mutual exclusivity among that group, but rather should be read as “and/or” unless expressly stated otherwise. Structures described herein are to be understood also to refer to functional equivalents of such structures. Language that may be construed to express approximation should be so understood unless the context clearly dictates otherwise.
Unless otherwise defined, all terms (including technical and scientific terms) are to be given their ordinary and customary meaning to a person of ordinary skill in the art, and are not to be limited to a special or customized meaning unless expressly so defined herein.
Terms and phrases used in this application, and variations thereof, especially in the appended claims, unless otherwise expressly stated, should be construed as open ended as opposed to limiting. As examples of the foregoing, the term “including” should be read to mean “including, without limitation,” “including but not limited to,” or the like; the term “having” should be interpreted as “having at least”; the term “includes” should be interpreted as “includes but is not limited to”; the term “example” is used to provide exemplary instances of the item in discussion, not an exhaustive or limiting list thereof; and use of terms like “preferably,” “preferred,” “desired,” “desirable,” or “exemplary” and words of similar meaning should not be understood as implying that certain features are critical, essential, or even important to the structure or function of the invention, but instead as merely intended to highlight alternative or additional features that may or may not be utilized in a particular embodiment of the invention.
Those skilled in the art will also understand that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations; however, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to embodiments containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C” is used, in general, such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.).
All numbers expressing dimensions, quantities of ingredients, reaction conditions, and so forth used in the specification are to be understood as being modified in all instances by the term “about” unless expressly stated otherwise. Accordingly, unless indicated to the contrary, the numerical parameters set forth herein are approximations that may vary depending upon the desired properties sought to be obtained.
The invention provides a system for water and waste stream evaluation and screen selection and/or sizing. The system may include a collection system, which may evaluate an area of collection system and length of sewer line, number and size of pump stations, pump type and presence of coarse screenings or grinding at stations, equalization or storage basins, and septage and grease hauler dumping. Additionally, a method is provided for evaluating a waste stream and selecting a screen relating to the same.
The system and methods may consider population factors, including density, hotels, resorts, laundry facilities, hospitals, sports stadiums, correctional and/or institutional facilities, and local industry. Headworks design may be considered for the evaluation, including length and slope of influent channel, number of channels and flow distribution, and/or pretreatment such as coarse screening or grit removal. Additionally, flow variations may be evaluated, including infiltration and intrusion, weather conditions like drought or heavy precipitation, and water use restrictions.
Just as each plant has its own characteristics that dictate the amount of screening protection it requires, every collection system and the waste flow it receives are unique as well. The design of a collection system, constituents feeding the plant, stormwater infiltration, and variations in flow all have a direct impact on the quantity, size, and consistency of screenings in the influent flow of any given treatment plant. WEF, in co-operation with ASCE, did a study of the screenings volume relative to flow collected at 39 U.S. wastewater treatment plants. Their results proved that plant screenings are so unique they differ by a factor of 70 times. Even conservative sizing used by most screen manufacturers cannot properly account for fluctuations in screenings of this magnitude when calculations are based on peak flow and opening size alone.
Having more detailed information about the contents of the waste flow in these applications is helpful in properly determining the correct screen type, grid, and size for the application. Some factors affecting fluctuations in the quantity, size, and consistency of screenings in the wastewater entering a municipal wastewater treatment plant are detailed below.
Illustrative benefits of flow analysis will now be discussed without limitation. Thorough analysis of flow to a treatment may provide an excellent return on investment. With focus on preliminary treatment, and screens in particular, the benefits extend from initial operation through the life cycle of the equipment selected.
The advantages of understanding the characteristics of solids in the waste stream begin with proper screen sizing to balance capital expense with long-term operation. To handle peak flows, a screen may be large enough to present enough open area to maintain appropriate water levels in the channel and velocities through the equipment. As solids blind the available open area, the screen may operate at sufficient speed and frequency to clean or present a new clean filtration area. The life of a screen's wear parts is determined by the speed and frequency in which the equipment is operated, therefore a larger screen operated slower and less frequently will outlast a smaller screen operated faster and more often. Flow analysis is an essential tool in determining the appropriate size screen to balance initial capital outlay and long-term screen operating costs.
Proper screen selection, sizing, and operation directly impact all downstream processes. If a screen is not protecting subsequent equipment as intended, maintenance costs can increase substantially while the life of that equipment can be reduced dramatically. Improper screening can also remove more organic material than desired. This can starve biological plant processes of the nutrients they were designed to treat while concurrently creating a screening disposal problem.
Visual inspection during flow analysis also provides useful information for design of screening handling and forecasting potential issues. Effective screening removes organic (fecal) and inorganic solids alike above a certain size. The higher amount of organic material the greater the plant's need for screenings handling, washing, and compaction. Examination of collected solids previews what the screens will collect and allows for proper screening handling design to separate inorganic and undesirable organic material for disposal while returning the biological content to the plant for treatment. An example of an undesirable organic material is a cotton rag. Identification of unexpected amounts of fibrous material, rags, grit, fats, oils, grease, and other large solids also aids in the screen type and opening selection. This may prevent potential surprises and poor screening performance.
Screening equipment will now be discussed. The screening equipment may include coarse and fine mechanical screening. Coarse screens are designed for removal of large solids and are meant for protection of pumps and collection systems. In municipal wastewater, they are often used in pump stations and CSO applications. While some treatment plants only operate with coarse screening, they are typically followed by finer screens further down the process. Normally coarse screens do not require screening, washing, or compaction as they primarily remove inorganic material and fecal washing is not necessary.
Fine screens are designed for medium to small solid size removal. In municipal wastewater systems, they are frequently incorporated into the preliminary treatment process at the headworks of a plant prior to grit removal. They are also used in pump stations, after grit removal and as a clarifier polishing when finer filtration is needed for protection of downstream processes. Because of the smaller openings, these screens remove larger amounts of fecal and organic material and are typically installed with screening handling equipment for washing and compaction of screenings prior to disposal.
Historically, mechanical coarse screens have openings larger than 1 inch while fine screens ranged as low as 0.25 inch. Over the last few decades, the sophistication of fine screens has improved and driven this range down. Currently, there are mechanical screens operating down to less than 1 mm in some municipal wastewater applications. It is generally recognized in today's market that coarse screens have openings down to 1 inch and fine screens below that. 6 mm or 0.25 inch is typical for fine screens. That “standard” continues to decrease with more sensitive downstream processes while screenings capture is increasing with improved designs and new opening types.
Opening types of the screening equipment will now be discussed along with the illustrations of FIG. 1 . There are three main types of mechanical screen grid openings: slotted, perforated and woven mesh. Each opening type has its advantages and limitations as well as suitable applications for use.
Slotted screen grids are typically manufactured of metal, found on coarser screens and can handle very large flows. They are commonly used with bar and continuous belt screens but are also used in other screen types. These screen types are used in water and wastewater treatment and while generally very durable and easy to unload they are less effective at removing smaller solids.
Perforated screen grids have circular holes machined or cut into plastic or metal panels and are found in finer screens with openings generally 0.25 inch or less. They are usually used in continuous belt screens in wastewater treatment applications. These openings capture the most screenings in wastewater applications but can have higher headlosses and require a spray wash to unload effectively.
Woven mesh grids are manufactured by framing wire mesh fabric with opening sizes generally less than 1 inch inside metal panels. They are also generally used in a continuous belt screen but are limited to water or treated wastewater applications as stringy materials are difficult to unload. Mesh opening screens can handle high volumes of water with low headlosses but are limited in solids they can remove and require a pressurized spray wash to unload captured screenings.
For wastewater treatment applications, slotted openings are commonly selected for coarser screens or where flow, channel, level, or lack of screening handling equipment limits higher screening capture. Perforated openings are increasing in popularity in wastewater applications because of their superior capture of solids but are sometimes not an option if an existing channel limits capacity or capture of organic material necessitates screening handling that is not desirable or affordable.
Selection of a screen type may be facilitated by considering one or more recognized evaluation of screen performance as Screenings Capture Ratio (SCR). A SCR is a measurement of the percentage of screenings a screen captures equal to or greater than its opening size. Thompson RPM, an independent testing facility based in the United Kingdom, and currently the only independent company actively engaged in testing screening equipment, recently published its findings on tests of SCR for more than 40 different screen designs. Chart 2-1 illustrated in FIG. 2 shows possible maximum, minimum, and average SCRs achieved for the different types of screening technologies tested at the facility. Their study tested 40+ screens of five different families (band, fine, screw, step, and slot) by eighteen different manufacturers with opening sizes from 1 mm to 7 mm and gives an accurate representation of the types of capture to be expected from screens of different families.
Screenings Capture Ratios may be considered when determining the proper screen for an application. Not all screens of the same opening size are created equal. As shown, even screens with the same opening size can have drastically different SCRs. In the 6 mm opening size the SCR was as low as 32% for a spiral style screen and as high as 84% for a center fed band style screen. A screen's orientation, unloading mechanism, sealing systems, and a number of other factors directly contribute to the amount of screenings a screen captures and retains.
This recent data regarding screen performance is useful in narrowing down a screen technology selection to a few screen types and opening sizes that are appropriate for a given application. From there, further evaluation should be made to ensure the proposed technology with the selected opening size is sized properly for the specific plant application.
Illustrative screen conditions and observations will now be discussed in the interest of clearly disclosing the present invention. The illustrative headworks at SCSD1 is an indoor facility that houses three screens. All of the screens at the headworks are multi-rake bar screens with a 0.25 inch opening. One of the screens is not functioning. The disassembled screw conveyor on the non-functioning screen is displayed in FIG. 3 .
The screen conveyor had to be disassembled because of the malfunctioning trough. The edge of the trough has broken and allows large solids to make it back to the system. The facility has rodents that may cause a sanitary issue if not addressed. The amount of screenings that are being removed from the channel on the bars is unsatisfactory. The solids that the system of the present invention is removing on the effluent side should be removed by the bars.
An example of the onsite screen sizing system will now be discussed. Throughout this disclosure, the onsite screen sizing system of the present invention may be alternatively labeled the “hydro-dyne onsite screen sizing,” or “H.O.S.S.,” system Skilled artisans should not view this alternative labeling to limit the present invention in any way.
The development of the H.O.S.S. system as a wastewater testing technology helps ensure the proper screen type has been selected for a unique application as well as correctly sizing the screen for the wastewater flow at a specific plant. The purpose of testing is to sample actual wastewater from the plant headworks and incorporate the findings in the design and proposal of screening equipment for that specific facility. The data may be compared to other tested facilities as well as interpreted through Hydro-Dyne's or another operator's experience in the performance of screening equipment to make proper recommendations. This can be an exclusive service offered by Hydro-Dyne Engineering to ensure that each proposed screen is designed specifically to cater to the needs of the plant in which it will operate.
The value of a screen specifically designed for the site constraints, downstream process and flow conditions to be experienced at a given plant cannot be understated. The detailed information collected pertaining to the consistency of the waste stream eliminates the guessing currently done by other manufacturers during screen design. Hydraulic calculations that are based on concrete data are accurate and unique for each plant. This ensures proposed screens are not over or under sized while still being designed to include appropriate safety factors. Benefits of a properly designed screen include: maximized SCR, which in turn leads to decreased maintenance across a plant, reduced screen maintenance, and increased screen life due to proper balance of idle versus run time, decreased capital costs attributed to oversized equipment and channels, prevents solids deposition prior to the screen and ensures that screenings handling units are designed to handle the solids expected to be captured by the screen.
Since it has been shown that not all screens of the same opening size perform equally, with SCRs between different style screens varying by as much as 50%, the H.O.S.S. system can also be used to measure the efficiency of an existing screen in service. By running trials both in front of and behind existing screens the H.O.S.S. system can be used to not only gauge the screens efficiency but also show the improvement in capture that should be expected for a screen of a different design and/or opening size.
The design of the onsite screen sizing system will now be discussed. The H.O.S.S. system is made up of various components specifically designed to pump wastewater from the waste stream through a simulated screening scenario and return it to the channel. The H.O.S.S. system may include intake piping, a flow meter, variable speed pump, multiple pressure sensors, the Sieve Assembly, discharge piping, and a programmable logic controller (PLC). The waste stream flow is pumped up through adjustable level intake piping, the flow meter, and sieve assembly before being piped back to the channel. The sieve assembly can accept slotted, perforated, and wire mesh sieve options simulating multiple opening shapes, sizes, and materials. The sieve assembly also allows two separate grids to be tested in series, simulating dual stage screening or stratifying screening size. Prior to each simulation, the parameters pertaining to each test (grid type, opening size, test duration, max differential, etc.) are programmed into the PLC via a touch screen panel. Data collected by the sieve assembly and flow meter is then stored by the onboard PLC for interpretation by Hydro-Dyne Engineering or another authorized operator. Ultimately, the data collected may include increasing pressure losses across one or more sieves as they accumulate material larger than the openings, which can be charted relative to flow to deduce the concentration of solids above a certain size in the waste stream. The information can be used to design a screen of appropriate grid style, opening size and available open area to filter the waste stream.
In the interest of clarity, testing of the system and methods of the present invention will now be discussed without limitation. The testing described below was performed using a number of general procedures. Testing of the waste stream may be conducted over the course of a single day from early morning to late afternoon so that tests may be run under a range of flow conditions. Multiple day testing procedures may be used if seasonal flows impact solids loading. Test samples can be pumped from the influent channel just upstream of the existing screen. Samples may be taken from a range of depths in the channel to ensure tests are representative of solids concentrations across the channel. Ideally, test may be run for each opening size or type from the middle and bottom of the channel.
If the required opening size of a screen has not been determined, multiple opening sizes and grid types may be tested to determine the proper screen grid type for the application. Depending on the number of openings being tested, multiple days of testing may be required in order to obtain a sufficient amount of data pertaining to the opening sizes being evaluated for proper screen sizing.
In the performance evaluation of an existing screen, tests may be run at multiple levels on the influent and effluent sides with multiple opening sizes. Data is collected to determine solids presented to the screen of certain sizes and solids of the same size passing through the screen. In cases where there is no existing screen, wastewater samples are removed from proposed locations of future screening equipment or at the head of the plant. The removed wastewater may then be analyzed using the H.O.S.S. system to determine the solids capture for each tested opening size.
Prior to each individual trial, the PLC may set to log the details of the specific trial about to be run. Each trial may run until the sample screen panel for the desired opening size reaches a determinable blinding measurement. When the trial is complete, the sample screen panel is removed, visually examined for blow through and hairpinning, photographed and then cleaned for retesting. The test kit technician may examine the screenings and note any distinguishing characteristics of the screenings sample. More extensive data can also be attained by collecting captured screenings for further analysis.
Once a set of trials is complete, the data collected by the equipment is analyzed by Hydro-Dyne's or another authorized user's design engineers. This data may be compared to the findings recorded by previous tests run at other plants as well as industry standard design criteria for screening equipment. This analysis may then be used to draw up a custom designed screening unit that is sized specifically for that plant's channel, flows and expected solids quantities.
With reference to FIG. 4 , plant specific testing will now be discussed. Those of skill in the art will appreciate that while the following example is provided by an instillation in a specific headworks and wastewater treatment plant, the installation and findings of the testing system may be applied to many other environments and installations. Therefore, skilled artisans should not view the following illustrative testing installation to limit the present invention in any way. The system of FIG. 4 provides a H.O.S.S. system setup inside a headworks at Saratoga County Sewer District No. 1 Wastewater Treatment plant. Skilled artisans will not view this testing configuration as limiting in any way. A list of illustrative tests executed at Saratoga County Sewer District No. 1 Wastewater Treatment Plant is provided in FIG. 5 .
Screen types were chosen based on hydraulic sizing. The tests were performed in the channel at the headworks. FIG. 6 provides a diagram representing where the tests were executed in relation to the screen and bottom of the channel. The approximate influent depth of the wastewater was 6 ft. Samples were removed 8 ft. from the front of the screen at depths of approximately 4 ft. and 2 ft. above the base of the channel. The tests performed on the effluent side of the screens were 6 ft. away from the screen because it allowed for the best access to the channel. The approximate effluent depth was 5 ft. and the samples were taken approximately 3 ft. from the base of the channel. FIG. 7 shows an illustrative placement of the pipe used to extract wastewater from the channel.
The pipe used to extract the wastewater to pass through the test kit was located in the center of the channel because the velocity of the flow is the fastest. Fast velocity is important because it allows the H.O.S.S. system to pump solids that have not settled out on the slower edges of the channel. Settling out can be caused by the velocity of the flow, the particle diameter, the density of the particle, and the shape of the screening. Below in FIGS. 8-11 are the sieves used in the test kit to represent the 6 mm slotted ( FIG. 8 ), 6 mm UHMW perforated panel ( FIG. 9 ), 2 mm metal perforated panel ( FIG. 10 ), and 4 mm metal perforated panel ( FIG. 11 ).
FIGS. 12-16 are photographic images illustrating other features, according to one or more embodiments of the present invention. In particular, FIG. 14 illustrates an embodiment of the system that may include an electric motor; storage container; control panel with programmable logic control, variable speed pump drive, and data recorder; intake for pump; housing for interchangeable sieves for testing flow through different size and shape openings; and output for tested flow returning to the plant.
Other Embodiments
It is to be understood that while the invention has been described in conjunction with the detailed description thereof, the foregoing description is intended to illustrate and not limit the scope of the invention, which is defined by the scope of the appended claims. Other aspects, advantages, and modifications are within the scope of the following claims. | A system and method for evaluating a flow pattern and downstream process for proper selection of screen type, opening and size for optimal screenings capture, operation time and capital outlay. The end result is a properly designed system that effectively protects downstream equipment and may save the customer money throughout the entire plant. | 6 |
This is a continuation of application Ser. No. 08/602,104 filed Feb. 23, 1996 (now U.S. Pat. No. 5,696,566) which is a divisional of Ser. No. 08/070,717 filed Jun. 1, 1993 (now U.S. Pat. No. 5,517,341).
BACKGROUND OF THE INVENTION
The present invention relates to a liquid crystal display and a manufacturing method thereof, and more particularly to an active matrix liquid crystal display and a method for manufacturing thereof capable of reducing the occurrence of such defects as short circuits between a gate line and data line and fractures of the gate line.
The present invention is an improvement over the invention which is the subject matter of the present inventors' co-pending U.S. application Ser. No. 07/934,396 which was filed on Aug. 25, 1992, and is now U.S. Pat. No. 5,339,181, the disclosure of which is hereby incorporated into this application by reference.
In response to a demand for personalized, space-saving displays which serve as the interface between humans and computers (and other types of computerized devices), various types of flat screen or flat panel displays, including liquid crystal displays have been developed to replace conventional display devices, particularly the cathode-ray tube (CRT), which is relatively large and obtrusive.
Liquid crystal displays have a simple matrix form and an active matrix form, using an electro-optic property of the liquid crystal whose molecular arrangement is varied according to an electric field. In particular, the LCD in the active matrix form utilizes a combination of liquid crystal technology and semiconductor technology, and is recognized as being superior to CRT displays.
The active matrix LCDs utilize an active device having a non-linear characteristic in each of a plurality of pixels arranged in a matrix configuration, using the switching characteristic of the device to thereby control the movement of each pixel. One type of the active matrix LCDs embodies a memory function through an electro-optic effect of the liquid crystal. A thin film transistor (hereinafter referred to as a "TFT") having three terminals is ordinarily used as the active device. A thin film diode (TFD), for example, a metal insulator metal (MIM) having two terminals, can also be used. In the active matrix LCD which utilizes such active devices, pixels are integrated on a glass substrate together with a pixel address wiring, to thereby provide a matrix driver circuit, with the TFTs serving as switching elements.
However, in the active matrix LCD whose display has a large screen, to obtain a high definition image, the number of the pixels are increased such that the aperture ratio of the individual pixels is decreased, thereby concomitantly reducing the brightness of the LCD.
To obtain a uniform image with on the active matrix LCD, it is also necessary that the voltage of a first signal applied through a data line be held constant for a certain time until a second signal is received. Also, in order to improve the image quality of the display, a storage capacitor is formed parallel with a liquid crystal cell.
To overcome the above-described problems, there has been proposed an active matrix LCD which has an additional light shielding layer and an independently wired storage capacitor to improve the characteristics of the display (see "High-Resolution 10.3-in Diagonal Multicolor TFT-LCD," M. Tsumura, M. Kitajima, K. Funahata et al., SID 91 DIGEST, pp. 215-218).
In the active matrix LCD according to the above paper, to obtain a high contrast ratio and high aperture ratio, a double light shielding layer structure is formed and the storage capacitor is formed of an independent wire formed separately from the gate line.
In the structure of the above double light shielding layer, a first light shielding layer is formed on a front glass substrate on which a color filter is provided and a second light shielding layer is formed on a rear glass substrate on which the TFT is provided. The LCD having such a double light shielding layer structure exhibits an aperture ratio which is improved by 6-20% over the conventional LCD having only the first light shielding layer. Also, a common electrode of the storage capacitor utilizes aluminum for the gate electrode whose resistance is only one-tenth that of the chromium (Cr) that is typically used for the gate electrode. Thereby, propagation delay characteristics along the scan line are improved.
However, the reduced aperture ratio, due to the usage of an opaque metal (aluminum) for forming the electrodes of the storage capacitor associated with each pixel, requires a longer recovery time.
Moreover, the second light shielding layer requires additional process steps, which unduly increase the cost and complexity of the LCD manufacturing process.
FIG. 1 is yet another pixel layout of a conventional liquid crystal display that attempts to overcome the problems associated with the LCD described by Tsumura previously. In this layout, an additional storage capacitor is formed. FIG. 2 is a cross-sectional view taken along line II--II of FIG. 1.
In FIG. 1, a single pixel region and portions of adjacent pixels surrounding it are illustrated. In a whole LCD, rows of gate lines 1 and orthogonal columns of data lines 5a are arranged in a matrix configuration. Thus, a pixel is formed in the regions bounded by these two kinds of lines. In each pixel region, a storage capacitor C, a thin film transistor (TFT) switching device, a light transmissive portion (aperture area), a transparent pixel electrode 4 and a color filter layer 21 are provided. Gate line 1 and data line 5a are referred to as scanning signal line and display signal line, respectively.
As can be seen in FIG. 1, the first electrode 10 of each storage capacitor C is formed as a tab-like portion projecting into a respective pixel portion from the scanning signal lines 1. Similarly, the gate electrode G of each TFT is also formed as an integral tab-like portion projected into a respective pixel portion of the scanning signal lines 1 (in the opposite direction to the corresponding first electrode of a storage capacitor). Each TFT system comprises a semiconductor layer 3 formed over the gate electrode G, a right tab-like protruding portion of display signal line 5a (drain electrode) adjoining the left end of semiconductor layer 3, a source electrode 5b adjoining the right end of semiconductor layer 3 and transparent pixel electrode 4. Transparent pixel electrode 4 is comprised of a transparent conductive material such as indium tin oxide (ITO).
All of the scanning signal lines 1, display signal lines 5a, capacitors C, TFTs, and pixel electrodes 4 are formed as part of a multilayer structure formed on the inward surface of a rear glass substrate 100. FIG. 2 illustrates a cross section of the aperture area for a pixel.
The process for forming an LCD having an additional storage capacitor is explained in more detail as follows. First electrode 10 of each storage capacitor C and each scanning signal line 1 are simultaneously formed by appropriately patterning an opaque conductive material (e.g., comprised of aluminum, chromium, molybdenum, or tantalum) previously deposited on the inner surface of the rear glass substrate 100 using a conventional photolithography process. Thereafter, an insulating layer 2 is formed over the scanning signal lines 1, first electrode 10 of capacitor C and the exposed regions of the inner surface of the rear glass substrate 100 as shown in FIG. 2. Next, the display signal lines 5a and transparent pixel electrodes 4 are separately formed, e.g., by successive photolithography processes. Then, a protective layer 6 is formed over pixel electrodes 4, display signal lines 5a, and the exposed regions of insulating layer 2, to thereby complete the multilayer structure disposed on the inner surface of the rear glass substrate 100.
With reference to FIG. 2, the prior art active matrix LCD further includes a front glass substrate 101 having a multilayer structure formed on the inner surface thereof, and oriented parallel to the rear glass substrate 100. For example, a black matrix 20 for light shielding is formed on the inner surface of front glass substrate 101. Black matrix 20 is formed by appropriately patterning a light-shielding layer, using a conventional photolithography process, to define the aperture area occupying each pixel electrode 4. Thereafter, a color filter layer 21 is formed over the black matrix 20 and the exposed areas of the inner surface of the front glass substrate 101. The color filter layer 21 includes light transmissive portions 21a disposed in the aperture area. Next, a protective layer 22 is formed over the color filter layer 21. Then, a transparent electrode 23 is formed over protective layer 22, to thereby complete the multilayer structure provided on the inner surface of the front glass substrate 101.
A thin layer of liquid crystal is then sandwiched between the front glass substrate 101 and the rear glass substrate 100, in contact with transparent electrode 23 and protective layer 6. Subsequent well-known process steps, fix together the front glass substrate 101 and the rear glass substrate 100 and the liquid crystal is then injected and sealed within the cavity formed therebetween.
In the active matrix LCD of the additional capacitor-type described with reference to FIGS. 1 and 2, since first electrode 10 of the storage capacitor and scanning signal line 1 are simultaneously patterned using the same material, an additional process step is unnecessary. Accordingly, the process for making the active matrix LCD can be simplified. However, it should also be appreciated that this device also suffers from certain drawbacks as follows. Since the first electrode 10 of each storage capacitor C is made of an opaque metal, and overlaps a significant portion of its associated pixel electrode 4, the aperture area of each pixel is significantly reduced by the corresponding overlap area, thereby reducing the aperture ratio.
Moreover, since the display signal lines 5a and pixel electrodes 4 are formed together on the same insulating layer 2, they must be separated by a predetermined distance to achieve electrical isolation. This further reduces the aperture area of the LCD and thus lowers the contrast ratio and luminance of the LCD.
FIG. 3 is a layout of the pixel of a liquid crystal display which has an independently capacitor, but differs from the Tsumura device previously described. FIG. 4 is a cross-sectional view taken along line IV--IV of FIG. 3, and shows only the lower part of the liquid crystal of the liquid crystal display panel. Line reference numerals as those of FIG. 1 and FIG. 2 represent the same elements.
As shown in FIG. 3, independently wired storage capacitor C uses transparent conductive material such as an indium-tin oxide (ITO) instead of an opaque metal, e.g., aluminum, as used in the above-mentioned conventional TFT-LCD. The light shielding layer structure formed around transparent pixel electrode 4 is not illustrated in FIG. 3. FIG. 3 shows only a single pixel and portions of surrounding pixels, each pixel defined by intersection scanning signal lines 1 and display signal lines 5a. Independently wired storage capacitor C is separated from scanning signal lines 1, differently from the additional capacitor-type shown in FIG. 1, and connected with the capacitor C in the adjacent pixel by an independent wiring 11, formed as a different conductive layer.
As shown in FIG. 4, the LCD having the independently wired capacitor utilizes inversely staggered TFTs as switching devices. Each gate electrode G, which is formed as a tab-like portion projected into each pixel and projecting from one of the scanning signal lines 1 portion, each first electrode 10a of storage capacitor C and each independent wiring 11, which is an extension of the first electrode, are formed parallel to the rear glass substrate of the liquid crystal display panel. Next, after insulating layer 2, such as a silicon nitride (SiN), is formed on the front surface, a semiconductor layer 3 and a transparent pixel electrode 4 are formed in a predetermined pattern. Display signal lines 5a and a source 5b are then formed thereon. Subsequent processes steps are accomplished using conventional methods.
Since the liquid crystal display using the independently wired storage capacitor as shown in FIGS. 3 and 4 utilizes transparent ITO for forming first electrode 10a of storage capacitor C, the aperture area does not decrease by as much the area of the electrode. However, since a light shielding layer does not exist on the rear glass substrate of the liquid crystal display panel along the edge of the pixel electrode, the contrast ratio is reduced so much. Also, an additional process step for forming the first electrode 10a of storage capacitor C is required. (This process is performed by depositing an additional transparent conductive material such as ITO, which is different from the opaque conductive material of the scanning signal lines, and then etching the transparent conductive material.)
To improve the problems exhibited in the above-mentioned liquid crystal displays of the additional capacitor-type (FIG. 1) and that of the independently wired type (FIG. 3), the aforementioned U.S. Pat. No. 5,339,181 includes a storage capacitor which faces a corresponding transparent pixel electrode and encloses the transparent pixel electrode in a ring (see FIGS. 5 and 6 show the invention disclosed in U.S. application Ser. No. 07/934,396). The same reference numerals as those of FIG. 1 or 4 represent the same components.
In a comparison to the devices of FIGS. 1 and 3, the active matrix LCD shown in FIG. 5 is manufactured using a conventional method. However, the layout of first electrode 10 of storage capacitor C associated with a pixel electrode 4 is arranged in the peripheral region of pixel electrode 4 to thereby increase the aperture ratio and contrast ratio of LCD. Specifically, the opaque metal layer from which the display signal lines 5a and the first electrodes 10 of storage capacitors C are formed is patterned in a manner such that the first electrodes 10 of storage capacitors C substantially surround their associated pixel electrodes 4 and, preferably, overlap only a peripheral edge portion thereof. As can be seen more clearly in FIG. 6 (taken along line VI--VI of FIG. 5), first electrode 10 of the capacitor C is disposed substantially beneath the matrix of black layer 20 provided on the inner surface of the front glass substrate 101, and does not extend into the envelope of the aperture area, thereby significantly increasing the aperture ratio compared with that of a conventional active matrix LCD.
Additionally, the first electrode 10 of each capacitor C formed along each corresponding pixel electrode 4 serves as an additional black layer, as illustrated in FIG. 6. That is, the first electrode 10 minimizes the amount of leak light passing through the aperture area of the front glass substrate 101 from the region of the liquid crystal located outside of the envelope of the aperture area.
In the conventional active matrix LCD depicted in FIG. 2, it can be seen that any extraneous light entering the front glass substrate 101 at an angle of incidence greater than Θ 1 is emitted through the aperture area of the front glass substrate 101. In the LCD of U.S. patent application Ser. No. 07/934,396, only extraneous light which enters the front glass substrate at an angle of incidence greater than Θ 2 is emitted through the aperture area of the front glass substrate as illustrated in FIG. 6. Excess light ("leak light") which strikes the front glass substrate whose angle is less than the angle of incidence Θ 2 is blocked by first electrode 10 of the adjacent storage capacitor. This LCD of FIG. 6 thus reduces the amount of leak light emitted through the aperture area of front glass substrate 101 by an amount which is proportional to the difference between Θ 2 and Θ 1 , thereby significantly increasing the contrast ratio.
Although the liquid crystal display having the ring-type storage capacitor improves display characteristics, it can be difficult to manufacture. Due to the introduction of foreign matter or a weak insulating film at wiring crossings (the intersection of scanning signal lines 1 and display signal lines 5a), wiring fractures in scanning signal lines 1 and/or short circuits between scanning signal lines 1 and display signal lines 5a occur, to thereby significantly lower the yield of manufactured liquid displays.
SUMMARY OF THE INVENTION
It is a primary object of the present invention to provide a liquid crystal display to which defects such as wiring fractures of the scanning signal line at the intersection of the scanning signal lines and display signal lines can be corrected.
It is another object of the present invention to provide a liquid crystal display to which defects such as short circuits occurring at the intersection of the scanning signal lines and display signal lines can be corrected.
It is a further object of the present invention to provide a liquid crystal display that improves the aperture ratio.
It is a still further object of the present invention to provide a liquid crystal display that improves the contrast ratio.
It is yet another object of the present invention to provide a method for simply manufacturing the liquid crystal display of the present invention with a minimum number of process steps.
According to the present invention the liquid crystal display contains a plurality of pixel regions bounded by the crossed scanning signal lines and display signal lines. Each pixel region contains a first electrode, which helps to maintain electric charge within the pixel region, so that the liquid crystal maintains its orientation. The first electrode is patterned to surround the aperture area containing the liquid crystal material.
In a first embodiment of the invention, each row of adjacent first electrodes are electrically connected together with redundancy connecting conductors.
In a second embodiment, there are two pairs of scanning signal lines associated with each pixel and electrically connected to the first electrode.
In both embodiments, conventional processing techniques without additional process steps are needed. Furthermore, according to the method of the invention, a laser can be used to correct any short circuits or fractures of the digital signal lines and the scanning signal lines. Thus, the overall yield can be improved.
BRIEF DESCRIPTION OF THE DRAWINGS
Further features and advantages will become more apparent from the following and more particular description of the preferred embodiment of the invention as illustrated in the accompanying drawings in which the same reference characters generally refer to like parts throughout the views, and in which:
FIG. 1 is a pixel layout of the conventional liquid crystal display formed using an additional capacitor-type method.
FIG. 2 is a cross-sectional view taken along line II--II of FIG. 1.
FIG. 3 is a pixel layout of the conventional liquid crystal display wherein an independent wiring-type storage capacitor is formed.
FIG. 4 is a cross-sectional view taken along line IV--IV of FIG. 3.
FIG. 5 is a pixel layout of the liquid crystal display wherein the additional capacitor-type storage capacitor is formed in a ring configuration.
Fig.6 is a cross-sectional view taken along line VI--VI of FIG. 5.
FIG. 7 is a pixel layout of the liquid crystal display according to the present invention wherein a ring-type storage capacitor having a redundancy connecting portion is formed.
FIG. 8 is a pixel layout of the liquid crystal display according to the present invention wherein a storage capacitor is formed as a double wiring method of a ring-type.
FIG. 9 is a schematic diagram showing an operational principle for explaining the effect of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 7 shows a pixel layout of a liquid crystal display according to one embodiment of the present invention.
Referring to FIG. 7, the liquid crystal display according to one embodiment of the present invention has a redundancy connecting portion 12 between a first electrode of a storage capacitor formed in each pixel region, in contrast to the pixel layout of the liquid crystal display shown in FIG. 5.
An opaque metal layer, from which the display signal line 5a and the first electrodes 10 of storage capacitors C are formed, is patterned so that the first electrodes 10 of storage capacitors C substantially surround their associated pixel electrodes 4 and, preferably, overlap only a peripheral edge portion thereof.
Moreover, first electrodes 10, like those shown in FIG. 6, are located under the matrix of black layer 20 provided on front glass substrate 101 and do not extend into the aperture area, thereby increasing the aperture ratio compared with the conventional LCD.
Additionally, first electrode 10 of each capacitor, which is formed to substantially surround each respective pixel electrode 4, serves as an additional light shielding layer. This minimizes the amount of leak light passing through the aperture area of the front glass substrate 101 from the regions of the liquid crystal located outside of the envelope of the aperture area.
Redundancy connecting portion 12, which is connected between the first electrodes 10 of each one of the storage capacitors, is simultaneously formed with first electrodes 10 and cross under display signal lines 5a. A dielectric insulating film is disposed in between connecting portions 12 and is tested, if it has a display signal line 5a.
When the liquid crystal display having the above-mentioned construction short circuit between the scanning signal line 1 and display signal line 5a at the wiring crossing portion, the scanning signal lines are cut by a laser beam on both sides of the crossing portion where the short-circuit has occurred, to thereby repair the short circuit. Thereafter, the signal which would have been transmitted by scanning signal lines 1 passes not through the cut scanning signal lines but through redundancy connecting portion 12. Moreover, since the signal is transmitted through redundancy connecting portion 12 when wiring fractures of scanning signal lines 1 occur at the crossing portion, flaws of this type are also repaired.
FIG. 8 shows a pixel layout of the liquid crystal display according to another embodiment of the present invention.
Referring to FIG. 8, the scanning signal lines 1 are duplicated as first signal electrodes 1a and second scanning signal lines 1b, compared with the pixel layout of the liquid crystal display shown in FIG. 5. Each plurality of the scanning signal lines, constituted by the first scanning signal line 1a and the second scanning signal line 1b, is arranged at predetermined intervals. Thus, in the FIG. 8 embodiment, first and second scanning signal lines 1a and 1b and display signal line 5a form the pixel boundary. The thin film transistor, is formed not on an integral tab-like portion of a corresponding scanning signal line 1a, but on the first scanning signal line 1a. Thus, the gate electrode of the thin film transistor is rotated 90° thereby to maximizing the aperture ratio of the liquid crystal display.
Meanwhile, an opaque conductive material layer from which the first electrodes 10 of storage capacitors C are formed, is patterned so that the first electrodes 10 of storage capacitors C substantially surround their associated pixel electrodes 4, overlap a peripheral edge portion thereof, and are connected with corresponding first and second scanning signal lines 1a and 1b on the same plane. When first electrode 10 is made of aluminum, the surface of the scanning signal lines and first electrode 10 is covered with aluminum oxide (Al 2 O 3 ) by an anodizing method.
Meanwhile, all of first electrodes 10 of the storage capacitor, like those of the devices shown in FIG. 6, are disposed under the matrix of black layer 20 located on front glass substrate 101. This serves as an additional light shielding layer for directly preventing the transmission of back light, which prevents incident leak light, to thereby increase the contrast ratio. During the time the display signal voltage is supplied to pixel electrode 4 and the liquid crystal display panel is driven, a predetermined voltage is also supplied between the transparent common electrode, which is provided over the liquid crystal, and first electrode 10 of the storage capacitor, so that the liquid crystal molecules become arranged perpendicular with respect to the substrate. Thereby, leak light is interrupted to increase the contrast ratio when a normally white mode exists.
The transparent substrate for the lower panel of the liquid display is a glass substrate, for example, Corning 7059 (product's name), with a thickness of about 1.1 mm. The scanning signal line is doubled by first scanning signal line 1a and second scanning signal line 1b and is connected around the driving circuit by a single wiring. When the whole line width of the doubled-scanning line is the same as that of the scanning signal line in the conventional single wiring method, the area of each crossing portion of the scanning signal line and display signal line is consistent and there also is no change in the wiring resistance of the scanning signal line.
In this embodiment, the thin film transistor switching device, is formed in an inversely staggered configuration. Scanning signal line 1 serves as the gate electrode to maximize the pixel area. However, a thin film diode (TFD), for example, a metal insulator metal (MIM), having two terminals can be used as the switching device instead of the thin film transistor.
FIG. 9 is a schematic diagram showing operation of the present FIG. 8 embodiment.
Scanning signal line 1 is connected by a single wiring to the driving IC circuit. Lines 1a and 1b are the first and second scanning signal lines, respectively. An arrow designates signal current flow when only one of first and second scanning signal lines 1a and 1b are providing a current path. Display signal line 5a is perpendicular to the scanning signal lines. In a portion A, first scanning signal line 1a is disconnected at the crossing portion of the first scanning and display signal lines. In a portion B, both first and second scanning signal lines 1a and 1b are disconnected. In portion C, a short circuit occurs between the second scanning line 1b and display signal line 5a which is correctable by means of a laser beam, the short can be repaired since the scanning lines are doubled. Portion D shows the repaired state of the short in portion C.
That is, since only portion B is not correctable, the overall percentage of operative devices is significantly increased.
The process of manufacturing the liquid crystal display according to the present invention will be explained below.
First, aluminum is deposited to a thickness of not more than 4,000 Å on the front surface of the rear glass substrate of the liquid crystal display. Scanning signal lines 1 and first electrodes 10 of the storage capacitors are then simultaneously formed.
First electrode 10 of the storage capacitor is formed with the ring-type structure, is extending to the edge of the pixel region, to enable utilization of the maximum pixel aperture area in both the embodiments of FIGS. 7 and 8. In making the FIG. 7 embodiment, redundancy connecting portion 12 is patterned to be connected between adjacent first electrodes 10 of the capacitors. In making the FIG. 8 embodiment, each paired scanning signal line is connected to each other.
In both the FIGS. 7 and 8 embodiments, since first electrode 10 serves as a light shielding layer, it should be comprised of an opaque conductive material that may be formed in a multilayer structure or by using an alloy.
When scanning signal lines 1 or first electrodes 10 is made of aluminum, using an anodic oxide method, the surfaces of the electrodes can be covered by the aluminum oxide film (Al 2 O 3 ) whose thickness is not more than 2,000 Å, to enhance electrical characteristic.
Thereafter, a pad is formed thereon for bonding display signal line 5a and scanning signal line 1 to the driving circuit. Here, for example, chromium is used as the pad metal whose thickness is about 2,000 Å.
According to another embodiment of the present invention, after forming a pad on the glass substrate, scanning signal line 1 and first electrode 10 may be formed thereon using an opaque conductive material other than, but still including, aluminum. Then, using a chemical vapor deposition (CVD) method, an insulating layer of a silicon nitride (SiNx) and a semiconductor layer of an amorphous hydride silicon (a-Si:H) are deposited to thicknesses of about 3,000 Å or below and 2,000 Å or below, respectively. At this time, the a-Si:H doped in an N-type (n + a-Si:H) is deposited as an ohmic layer on the a-Si:H to a thickness of approximately 500 Å. Thereafter, as shown in FIGS. 7 and 8, the semiconductor layer is patterned so as to define an area in which the switching device will be placed on scanning signal line 1 or its nearby portion.
The insulating layer on the connecting portion of the driving IC is removed, and a transparent conductive material, e.g., an ITO, is thereafter deposited to a thickness of about 500 Å or below via a sputtering method, and patterned to thereby form pixel electrode 4. At this time, pixel electrode 4 is patterned to overlap first electrode 10 of the storage capacitor by a predetermined width. A capacitor is thus formed between first electrode 10 of the storage capacitor and pixel electrode 4 on the pixel area with a dielectric insulating layer material in between, so that a voltage signal input through display signal line 5a is maintained for a predetermined time period till the following input.
Then, after the opaque corrective material such as chromium and aluminum are consecutively deposited on the whole surface of the substrate to a thicknesses of about 500 Å or below and 5,000 Å or below, respectively, via a sputtering method, display signal line 5a and source and drain electrodes of the TFT are patterned and a protective layer of silicon nitride is deposited on the whole surface of the substrate to a thickness of about 4,000 Å via a CVD method. Hence, the lower substrate of the LCD is completed. Using known LCD technology, an aligning layer for aligning the liquid crystal can be formed on the protective layer in a succeeding step.
The upper substrate of the LCD is completed so that, after the aperture area of the LCD has been defined, a light shielding layer is formed on the inner surface of the transparent front glass substrate as matrices along the periphery of each pixel area. The light shielding layer and exposed aperture area are then covered with a color filter layer, and an ordinary protective layer and transparent upper common electrode are successively formed thereon, thereby completing the multi-layer structure.
The above-described lower and upper substrates of the LCD are supported by supporting rods, and liquid crystal is injected between them. The substrate are then sealed, thereby completing the LCD.
While the present invention has been particularly shown and described with reference to particular embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be effected therein without departing from the spirit and scope of the invention as defined by the appended claims. | An active matrix-type liquid crystal display is described having, for each pixel, a first electrode for of a storage capacitor that is connected to a scanning signal line. The liquid crystal display can be repaired for disconnections and short inferiorities occurring in a crossing portion of scanning signal line. A redundancy correcting line connects the capacitor electrodes of adjacent pixels. Also described is a double scanning signal line. The embodiments using the redundant connecting line and double scanning signal line are both repairable using laser if imperfections exist. Thus, while maintaining high aperture and contrast ratios, the disconnections and shorts in the crossing portion of wirings can be minimized. | 6 |
FIELD OF INVENTION
[0001] This disclosure relates generally to methods and devices for adding structural support to walls lacking sufficient structural support. Specifically, this disclosure relates to a device and method for inserting a curable material behind the surface of a wall to create an anchor point to a wall for providing additional structural support to the wall.
BACKGROUND
[0002] When attaching an article to a wall, either the wall itself must be capable of supporting the article, or the article must be attached so that it engages a supporting element behind the wall. This is especially true when the article is heavy, or the article is subject to repeated stresses. It is well know to most homeowners that in order to secure articles of significant weight, such as mirrors, pictures, shelves, light fixtures and the like, to a finished wall, the article must be secured to a frame stud behind the finished wall. In addition, articles that will undergo repeated stresses, such, as towel bars, cabinets, hooks and the like, must also be secured to a frame stud. If these articles are not secured to a frame stud, the articles may not remain secured to the wall, causing damage to the finished wall and possible injury to those nearby. In the case of most residential dwellings the frame studs are composed of wood. In other instances, the frame stud may be composed of aluminum or other metal. In either case, the frame studs are generally placed about 14 ½ inches apart in standard construction methods. As a result, in many cases there is not a frame stud available to secure an article in the selected location.
[0003] When this problem occurs, the options are to: 1) find an alternate location for the article where there is access to a frame stud; 2) insert a spring-loaded wingnut or similar device into the wall to secure the article to the wall; or 3) insert a blocking element, such as a section of wood, behind the wall to secure the article to the wall. Each of these options has advantages and disadvantages. Option number one, while being the simplest option, is not feasible in some instances as the article would not be functional in the alternate location, or would not have the desired aesthetic qualities in the alternate location. Options two and three allow the article to be placed in the desired location, but each suffers from its own drawbacks. The use of spring-loaded wingnuts or similar devices have the advantage that they are relatively simple to install, requiring only that a hole be drilled into the finished wall to receive the wingnut or other device. However, these devices do not provide a point of attachment of sufficient strength to secure heavy articles to the finished wall. In addition, over time, especially if the article is subject to repeated stress, the wingnut or other device will eventually cause damage to the sheet rock, or fail altogether. In such an instance, the finished wall may require extensive repairs to return it to its original condition. Option number three requires that the area behind the finished wall be “blocked,” typically with a section of wood or other material secured between two existing frame studs on either side of the point of installation. In this case, the blocked section receives the article and secures the article to the wall. The blocking method has the advantage that it is capable of securely fastening heavy articles to the wall so that they can withstand repeated stresses over time, but suffers from the drawback that installation of the blocking element is very labor intensive, time consuming and expensive. For example, installation of a wood block behind a finished wall made of sheet rock requires making a hole in the sheet rock wall large enough to expose the two frame studs on either side of the installation point, nailing the wood block to each frame stud, applying new sheet-rock to the hole created, applying mud to the new section of sheet rock, sanding the newly applied mud, applying a second coat of mud, re-sanding, priming the new sheet rock section and applying new paint or wall paper to the new finished wall section. If the finished wall is made of plaster or other material, the process may even be more involved.
[0004] As can be seen from the above discussion, a device and method are needed for adding structural support to a wall, such that the reinforced wall is able to securely receive heavy loads and stresses without failing or becoming damaged over time. The device and method should be simple to use and install, economical and provide at least as much strength as current alternatives, such as blocking with wood.
SUMMARY
[0005] The present disclosure describes a device and method for the creation of anchor points at any point in a wall through the application of a curable anchor material. The anchor material is injected behind the wall and allowed to cure. Once cured, the newly created anchor point will allow the wall to support heavy loads and undergo repeated stress without being damaged.
[0006] The device of the present disclosure is in its most general form a bladder, with openings, or adhesion points, therein which is packaged in a deflated state in a protective housing. The bladder is fluidly connected to a source of anchor material by a connecting means. Once the device is inserted behind the wall, the device is ready for use. On activation of the device, anchor material is dispensed from the source into the bladder through the connecting means. The anchor material is metered to expand the bladder beyond its capacity, causing the anchor material to be extruded through the adhesion points on the bladder into the space behind the wall. The anchor material adheres to everything it contacts, and creates a structural anchor point capable of securing heavy articles such that they can withstand repeated stress over time. After the anchor material has set (usually 10-30 minutes), the protruding portion of the device is snapped off at a pre-engineered breakpoint so that the portion of the device remaining is flush with the outer wall.
[0007] The anchor material may be any single or multi-component system, such as polyesters, or other high density structural foams with the necessary cured physical properties to handle heavy loads and repeated stress over a long period of time, while meeting all building codes. The area of the anchor point will depend on the size of the bladder used, the amount of anchor material used and the wall space available. For typical household uses, the device will be engineered to create an anchor point from 4 to 16 inches in diameter.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] [0008]FIG. 1A is a side elevation view illustrating one embodiment of the device, with the device shown in its pre-activation state;
[0009] [0009]FIG. 1B is a side elevation view of the device shown in FIG. 1A further illustrating the housing and one embodiment of the breaking means;
[0010] [0010]FIG. 2A is a side elevation view illustrating an alternate embodiment of the device, with the device shown in its pre-activation state;
[0011] [0011]FIG. 2B is a side elevation view of the frangible inner ring illustrating one embodiment of the notched sections; and
[0012] [0012]FIG. 3 is a side elevation view illustrating the embodiment of the device shown in FIG. 1A, with the device shown in its post-activation state.
DETAILED DESCRIPTION
[0013] Definitions
[0014] The following terms should be given the following meanings in this specification, the drawings and the claims that follow:
[0015] anchor point shall mean the area of structural support created by the anchor material;
[0016] article(s) shall mean any fixture, accessory, device, or other object that is capable of being secured to a wall;
[0017] blocking shall refer to the process of adding additional support to the backside of a sheet rock panel or other surface which requires reinforcement;
[0018] frame stud shall mean any structure, usually vertically oriented, regardless of composition that supports a wall;
[0019] wall shall mean any surface, including, but not limited to, walls, ceilings, floors, decks and roofs, but shall not be restricted to flat planar surfaces;
[0020] The present disclosure is designed to overcome the deficiencies in the devices and methods currently available for blocking walls. The devices and methods currently available are either incapable of securing heavy articles to a wall for extended periods of time, or are too time consuming and expensive to be a viable option for the majority of users. The present disclosure describes a simple device for creating an anchor point behind any wall, so that the wall is able to support articles of significant weight and articles that are subject to repeated stresses. The device and method are simpler to use than current blocking methods, produce a reinforced area that is at least as strong as that produced by currently blocking methods and requires only about 10-30 minutes for installation.
[0021] Referring now to the drawings where like reference numerals have been used throughout the various figures to designate like items, FIGS. 1 and 2 illustrate two embodiment of the device of the present disclosure. Generally, the device comprises a source of anchor material fluidly connected to an inflatable bladder by a connecting means. The function of the source of anchor material is to maintain the anchor material and/or its components in a state so that upon activation of the source, the same can be delivered in a functional state to the bladder. The function of the connecting means is to provide a fluid connection between the source of anchor material and the bladder. The exact configuration of the source of the anchor material and the connecting means can be varied, with two embodiments shown below being for illustration of the overall concept of the present disclosure. FIGS. 1 and 2 show the device before activation.
[0022] [0022]FIGS. 1A and 1B illustrate one embodiment of the device. In this embodiment, the device 10 comprises a source of anchor material 20 and an inflatable bladder 16 and a connecting means comprising an insertion tube 12 fluidly connected to a discharge tube 44 . The insertion tube 12 has a first end 14 and a second end 18 , with the first end 14 secured to the bladder 16 . The bladder 16 is attached to the first end 14 by any convenient means, such as a heat seal, a glue seal or a crimping seal. The insertion tube 12 is fluidly connected on its second end 18 to the discharge tube 44 . The connection may be by any convenient means, such as a standard male/female threaded connection, a pressure connection, luer coupling, snap-fit coupling or bayonet coupling. FIG. 1A shows the connection made by virtue of a standard male/female threaded connection 40 . The insertion tube 12 and discharge tube 44 may also contain static mixing elements 45 to ensure the anchor material remains mixed during transit from source 20 to bladder 16 . In addition, the insertion tube 12 may have a stop 54 extending at along at least a portion of the circumference of the insertion tube 12 . As shown in FIGS. 3 and 3B, the insertion tube 12 is inserted into the cavity 30 and pushes the bladder 16 out the first end 24 of the housing 22 and into the interior 64 of the wall 60 . The stop 54 on the second end 18 of the insertion tube stops the inward motion of the insertion tube 12 , and prevents damage to bladder 16 .
[0023] The bladder 16 and the first end 14 are preferably contained, at least partially, within a protective housing 22 . The exact configuration of the housing is not critical, but the overall area of the housing should be as compact as possible. As shown in FIGS. 1A and 1B, the 40 housing is illustrated as being generally circular in shape. In FIGS. 1A and 1B, the housing 22 comprises a sealed, frangible first end 24 and an open second end 26 , the ends connected by a circular outer wall 28 . The first end 24 , the second end 26 and the outer wall 28 defined a cavity 30 to receive at least part of the bladder 16 . The open second end 26 functions to receive the first end 14 of the insertion tube 12 , and may be tapered to snugly receive the first end 14 . In addition, the outer wall 28 further comprises a stop 32 extending around at least a portion of the periphery of the outer wall 28 . The stop 32 can be located at various positions along the outer wall 28 , but it is preferred that the stop 32 be placed so that the first end 24 extends at least partially into cavity 64 (shown in FIG. 3). The location of the stop 32 can be varied as required. The stop 32 may be engineered to include notched wall sections 34 to allow the outer wall 28 to be separated into 2 pieces at the location of the notched wall sections 34 . The notched wall sections 34 are preferably located immediately next to the stop 32 and on the side of the stop proximal to the first end 24 . In addition, snap anchors 70 may be placed on the outer wall 28 on or near the first end 24 . The snap anchors 70 are angled to allow the first end 24 of the device 10 to be inserted through the wall 60 , but to engage wall 60 to prevent unintentional removal of the device 10 (shown in FIG. 3).
[0024] In FIG. 2A, an alternate embodiment of the device is shown. While the device 100 comprises the basic elements of a source of anchor material 20 , inflatable bladder 16 and a connecting means, the embodiments of these elements are different than that shown in FIGS. 1A and 1B. The device 100 comprises a protective housing 122 . The housing 122 comprises a sealed, frangible first end 124 and a second end 146 . The first end 124 and second end 146 are connected by a circular outer wall 128 . The first end 124 , the second end 146 and the outer wall 128 defined a cavity 130 to receive at least part of the bladder 16 . The second end 146 has a connecting means adapted to receive a complementary connecting means on discharge tube 144 . The connection may be by any convenient means, such as a standard male/female threaded connection, a pressure connection, luer coupling, snap-fit coupling or bayonet coupling. FIG. 2A shows the connection made by virtue of a standard male/female threaded connection 140 . In addition, the outer wall 128 further comprises a stop 132 extending around at least a portion of the periphery of the outer wall 128 . The stop 132 can be located at various positions along the outer wall 128 , but it is preferred that the stop 132 be placed so that the first end 124 extends at least partially into cavity 64 . The location of the stop 132 can be varied as required. The stop 132 may be engineered to include notched wall sections 134 to allow the outer wall 128 to be separated into 2 pieces at the location of the notch ed wall sections 134 . The notched wall sections 134 are preferably located immediately next to the stop 132 and on the side of the stop proximal to the first end 124 . The function and operation of the notched wall sections 134 is analogous to the function and operation of the notched wall sections 34 described above. In addition, snap anchors 170 may be placed on the outer wall 128 on or near the first end 124 . The snap anchors 170 are angled to allow the first end 124 of the device 100 to be inserted through the wall 60 , but to engage wall 60 to prevent unintentional removal of the device 100 (shown in FIG. 2A). The bladder 16 is secured to snap anchors 170 by any convenient means, such as a heat seal or a glue seal.
[0025] Referring to FIG. 3 which shows the embodiment of the device illustrated in FIGS. 1A and 1B after activation, the bladder 16 is generally spherical in shape and is composed of an elastic material (the principles described below and illustrated in FIG. 3 also applies to the embodiment illustrated in FIG. 2). Other shapes for the bladder 16 can be engineered if required for certain applications, such as rectangular blocks. The bladder 16 may contain a plurality of pre-engineered adhesion points 38 around the outer surface of the bladder 16 . The adhesion points 38 are simply openings to allow the anchor material 62 to escape the bladder 16 and come into contact with structures behind the wall 60 when the device 10 is activated. The number of adhesion points 38 on bladder 16 can be varied to fit individual applications. The interior volume of the bladder 16 can be adjusted depending on the intended use of the device. For a typical use of providing an anchor point in a interior residential wall, the volume of the balloon is 65 inches 3 (in 3 ) to 400 in 3 , preferably 230 in 3 . This will produce a finished anchor point of 4 to 16 inches in diameter. The volume of the bladder 16 , the diameter of the anchor point and the shape of the anchor point can be changed if desired.
[0026] Turning to a discussion of the source of anchor material 20 , the source 20 delivers the anchor material 62 , at sufficient speeds and pressure to the bladder 16 when the device 10 is activated. The pressure required on activation is dependent on the viscosity of the anchor material and its components, but is sufficient to ensure the anchor material is sufficiently mixed and dispensed into the inflatable bladder. The source 20 , therefore, may be any means that meets these requirements. Preferably, the source 20 is self contained and is portable for ease of use.
[0027] [0027]FIG. 1A shows a standard aerosol can 42 as one embodiment of the source 20 . The can 42 is of standard design, with a discharge tube 44 fluidly connected to at least one anchor material storage chamber 46 and a propellant chamber 48 at one end and the insertion tube 12 at the other. The end of the discharge tube 44 that connects to the insertion tube 12 may be flexible to facilitate ease of use. The activation means is shown in FIG. 1A as valve 52 . On depression of valve 52 , anchor material flows from the at least one storage chamber 46 , through the discharge tube 44 and insertion tube 12 into the bladder 16 .
[0028] In an alternate embodiment shown in FIG. 2A, the source 20 is a container 150 . The container 150 is separated into 2 compartments, 152 and 154 by a frangible separation means. The separation means functions to separate the components of the anchor material prior to activation, but can be ruptured when desired to allow the components of the anchor material to mix with one another. In FIG. 2A, the separation means comprises a planar O-ring 156 and a coupling shaft 158 . The diameter of O-ring 156 is selected to conform to the diameter of container 150 and contains a frangible portion. The frangible portion comprises an inner ring 162 and a center portion 164 , for connection to the coupling shaft. The inner ring 162 is constructed so that the seal integrity is comprimised on rotation of coupling shaft 158 . As illustrated in FIG. 2B, inner ring 162 may contain notched sections 166 for this purpose. The number and placement of notched sections 166 is not critical, with the embodiment shown in FIG. 2C illustrating 2 notched sections 166 . The coupling shaft 158 extends beneath the container 150 . The device is activated by rotating the coupling shaft 158 in either direction. The rotation breaks the inner rings 162 at notched sections 166 , allowing the components of the anchor material stored in compartments 152 and 154 to interact and mix. On mixing, the components of the anchor material undergo a chemical reaction, forming a foam and expand in volume 3-5 fold. The expansion forces the anchor material through the discharge tube 144 and into the bladder 16 , causing bladder 16 to expand. In this manner, the coupling shaft 158 serves as the activation means, with activation occurring on rotation of the activation shaft 158 .
[0029] Although specific embodiments of the source 20 have been illustrated with specific embodiments of the connecting means and protective housing, it should be understood that the various embodiments can be interchanged as desired to produce the device.
[0030] The anchor material may be any single or multi-component system that is capable of providing the necessary cured physical properties to handle heavy loads and repeated stress over a long period of time. Examples include, but are not limited to, structural polyurethane foam, thermoset plastics, polyester, foamed polymer concrete or modifications or combinations thereof. A preferred formulation of the anchor material is structural polyurethane foam with a density of 30 pounds per cubic foot in combination with non-elastic spheres. Preferably, the spheres are ceramic spheres, present at a concentration between 10% and 30% by volume. The diameter of the ceramic spheres is preferably from 0.005 inches to 0.008 inches. However, the composition, concentration percentage and diameter of ceramic spheres can be varied depending on the desired cured physical characteristics of the anchor material. The structural polyurethane foam described above is a two component system and generally requires 10 to 15 minutes to cure. A properly cured structural polyurethane foam anchor point can withstand over 300 pounds of screw pulling force. This force meets or exceeds the force that can be withstood by traditional blocking methods and materials, such as wood.
[0031] The device is simple to use in operation, as illustrated in FIG. 3. FIG. 3 shows the device illustrated in FIGS. 1A and 1B. At any point in a wall requiring an anchor point, the user drills a hole 66 at the desired location in the wall 60 . In most applications for home use, a ½ inch hole is sufficient for operation of the device. The user then inserts the device 10 into the hole 66 . As shown in FIG. 3, the first end 24 of the housing 22 is inserted into the hole 66 . The stop 32 engages the outer surface of the wall 60 and stops the insertion of the device 10 at the proper point. Optional snap anchors 70 engage the interior side of wall 60 in response to the back pressure generated by the inflation of bladder 16 and prevent the device 10 from backing out of hole 66 . Once the device 10 is position in the hole 66 , it is ready for use. The user initiates the flow of anchor material 62 by engaging the activation means, in this case depressing valve 52 . Once activated, anchor material 62 flows from the at least one storage compartment 46 through the discharge tube 44 , into and through the insertion tube 12 and into the bladder 16 . If static mixing elements 45 are employed, the anchor material 62 is mixed as it travels through from the source 20 to the bladder 16 . The anchor material 62 expands the bladder 16 to its maximum volume while leaking from the pre-engineered adhesion points 38 in the bladder 16 . The anchor material 62 engages the back surface of the wall 60 and other structures contained within the interior 64 of the wall to form the anchor point. As discussed above, the size of the anchor point will depend on the volume of the bladder 16 and the amount of anchor material 62 used. These parameters may be altered to suit specific applications.
[0032] The anchor material is allowed to cure for 10 to 30 minutes. Once the curing process is complete the anchor point is ready for use. As the device 10 is still inserted into the hole, the user applies a slight lateral pressure to the device on the outer wall 28 . This pressure causes the device 10 to snap along the preformed notches 34 . The device 10 from the stop 32 to the second end 26 is then removed from the wall 60 . The result is a flush surface that is ready for sanding, priming and painting or other finishing. Alternatively, if finishing the wall is not desired, the unfinished area of the wall created by the use of the device 10 is so small, the article may be mounted so that the unfinished area is covered by the article.
[0033] The anchor point created by the device and method of the present disclosure has many advantages over the blocking methods of the prior art. First, pound for pound the anchor point formed according to the present disclosure is stronger than the strongest of the blocking methods in current use. Second, the installation of the anchor point formed according to the present disclosure is simpler to install and requires minimal destruction of the wall surface to be reinforced. Current blocking methods require a large hole to be cut into the finished wall sufficient to expose two frame members. A section of wood must then be nailed to the frame members to block or reinforce the wall section. Finally, the finished wall must be replaced and finished. In contrast, the anchor point formed according to the present disclosure only requires the drilling of a small hole in the wall, without the need for extensive replacement and finishing. Third, when installation and repair costs are factored in, the anchor point formed by the present disclosure is up to $200 to $300 less expensive than current blocking methods. The result of the device and method described above is a reinforced area in the wall that is capable of securing heavy articles over long period s of time without causing damage to the wall.
[0034] The above discussion has described several embodiments of the device in detail so that the device and its principles of operation may be understood. The above discussion should not be interpreted to exclude additional embodiments of the device. With respect to the above description, it should be considered that the optimal dimensional relationships for the various parts of the invention, including variations in size, materials, shape, form, function and manner of operation, assembly and use, are readily apparent to one of ordinary skill in the art, and all equivalent relationships to those described above and illustrated in the figures are intended to be encompassed by the present disclosure. Therefore, the foregoing is considered illustrative only, and should not be understood to limit the scope of the disclosure to the exact construction and operation discussed and illustrated. | The present disclosure describes a device and method for the creation of a anchor points at any location in a wall through the injection of a curable anchor material into the cavity behind the wall. Once cured, the newly created anchor point will allow the wall to support heavy loads and undergo repeated stress over long periods of time without being damaged. The device of the present disclosure produces anchor point that is at least as strong as the best methods currently available, yet is simpler and more economical to use than the methods currently available. | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This patent application is a Continuation of co-pending U.S. patent application Ser. No. 10/696,386, filed Oct. 29, 2003, entitled METHOD AND SYSTEM FOR REMOTE CONTROL OF A LOCAL SYSTEM, which is a Continuation of U.S. patent application Ser. No. 09/430,464, filed Oct. 29, 1999, now U.S. Pat. No. 6,675,193, entitled METHOD AND SYSTEM FOR REMOTE CONTROL OF A LOCAL SYSTEM. The contents of each of these application(s)/patent(s) is hereby incorporated by reference herein in its entirety for all purposes.
FIELD OF THE INVENTION
[0002] This invention relates generally to data processing systems. More particularly but not exclusively, the invention relates to a method and system for accessing remote computer systems and operating at least one particular instance of a program running on the local computer on the remote computer system.
BACKGROUND
[0003] Many programs are currently implemented in object-oriented programming languages, such as the C++ programming language. The display icons that represent data or resources are typically representations of data structures called objects, which encapsulate attributes and behaviors. Objects are specified by definitions, called classes, that specify the attributes and behaviors of the particular objects, which are termed “instantiations” of the class definitions. The reference Budd, T., “An Introduction to Object-Oriented Programming,” Addison-Wesley Publishing Co., Inc. 1991, provides an introduction to object-oriented concepts and terminology.
[0004] Object-oriented programming languages make it easier for system programmers to implement the Graphical User Interface (GUI) concepts of icons and lists. For example, if the GUI icons are represented as object-oriented programming objects, the GUI program can be written so that the status of the icon is continuously updated. In this way, it is relatively simple for the GUI program to be written so that the icons can be selected with the graphical user input device and moved about on the computer system display as desired.
[0005] With the advent of object-oriented languages also came object-oriented development environments. Such development environments are computer programs or groups of computer programs that allow a software developer to create object-oriented programs. Object-oriented development environments typically have a palette of objects with which the developer builds an application. Each object on this palette is different and serves as a template for the developer. A palette object's attribute settings are the default settings for that object. To use an object on the palette, the developer copies the object and places the copy on the application. The copied or “derived” object has the same attribute settings as the original palette object. These development environments also permit the developer to modify an object and save it as another palette object or create an entirely new object.
[0006] Efforts have been made to establish a common method of communication between objects instantiated within a given operating system environment. For example, Microsoft Corporation has established a protocol, known as the Component Object Model (COM), which governs the interaction between software objects within the Microsoft Windows operating environment. COM provides a standard framework which penn its objects from different applications to share data and functions. COM also permits a given application program (“container application”) to contain multiple objects of different types. A format for control objects known as “ActiveX” has been established to take advantage of the COM protocol. An ActiveX object behaves as a “server” relative to its container application, which in turn behaves as a “client.” The COM protocol manages, among other things, the setup and initialization necessary for container applications to send and receive messages and data to and from server applications.
[0007] In the context of an ActiveX control, stored data members are known as “properties,” functions are referred to as “methods,” and event occurrences are denoted as “events.” Properties can be read from, and written to, an ActiveX control via associated methods. The interface of an ActiveX control is a set of methods defining certain input, output and behavior rules. Accordingly, a container application can invoke the methods. of an ActiveX control to effect the defined behavior and access the object data.
[0008] In addition to representing data stored by an ActiveX control, properties are used in formatting the display of an ActiveX control. Events are utilized to notify a container application of the occurrence of an event, as well as to pass parameters relevant to the particular event. For example, an ActiveX control is capable of informing its container application of the occurrence of a selection event (e.g., when the user interface of the control has been “clicked on”).
[0009] ActiveX objects are typically implemented either as in-process servers where the ActiveX control is implemented as a Dynamic Link Library (DLL), or as out-of-process servers as an “executable.” ActiveX DLLs are loaded into the process space of the container application. As a consequence, data does not need to be transported between the container application and the ActiveX control. In contrast, ActiveX executables are loaded into a separate process space from the container application. Since there is no shared memory between such applications, data is transported between ActiveX objects and the container application. This is advantageous in the sense that an ActiveX executable does not interfere with the processing of data in the client application.
[0010] Although a number of programming environments exist for facilitating development of ActiveX controls as object-oriented constructs, each such ActiveX control operates independently of the container application. That is, ActiveX controls are conventionally installed in container applications so as not to be affected by changes in parameters of the container application, and vice versa. Similarly, the occurrence of ActiveX events does not automatically cause the execution of scripts or the like in the container application.
[0011] Early remote control systems were designed to access and take over the local computer system and run them from a remote location, eliminating any other access and remote operation, as noted in Hyatt (U.S. Pat. No. 5,307,403) and Zapolin (U.S. Pat. No. 5,122,948).
[0012] Existing systems as typified by Slaughter (U.S. Pat. No. 5,598,536) permit accessing of data from a local controller system, for example, and the collection of data from the local controller data memory, such as, sensor and other data, as well as the sending of instructions to the controller to set or control certain switches.
[0013] Still other systems, as typified by Crater (U.S. Pat. No. 5,805,442), provide for the existence of controller-based web pages which are sent over the Internet and viewed in a browser which accesses the controller as a node on the Web.
[0014] Other systems as typified by the Mercury Project papers entitled “Desktop Teleoperation via the World Wide Web”, and “Beyond the Web: Excavating the Real World Via Mosaic” which are attached hereto and incorporated herein by reference, show multiple servers which collect data, configure web pages and provide security features for communication and the exchange of control systems data with multiple clients on the Web.
[0015] Each of these systems uses the application running on the local system for control of the local control systems. The browser systems utilize the browser simply as a data input and display device which exchanges data and instructions with the local system.
SUMMARY
[0016] In one or more embodiments the present invention is directed to systems and methods for remote control by at least one controller for sending and receiving remote and local control system information wherein the controller gathers local control system information and transmits the local control information over at least one communication path to at least one remote computer system (client). A desktop bound program can be run on a remote computer utilizing remote data without changing the desktop software.
[0017] The client applications can be made to execute in any context that can host an ActiveX control. This has been accomplished by modifying the local runtime application, which in the specific embodiment is a window viewer, to become a local server and to provide an ActiveX control object to host the server.
[0018] The client application can be run from a browser or via the command line.
[0019] The remote computer system runs a remote software application and manipulates the transmitted local control information.
[0020] The remote control system information can be stored in the local computer's controller memory. Alternatively, the remote control system information can be stored in the remote computer's system memory.
[0021] The controller may contain one or more data handlers. Examples of data handlers include: a runtime database handler, an alarm data handler and a history data handler. Customized handlers can be created using a data handler toolkit.
[0022] The communication paths include secure (e.g., HTTPS) and non-secure (e.g., HTTP) paths. Multiple communication paths can be operable in a single session.
[0023] Additional aspects of the invention are described and illustrated herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a block diagram of a computing environment suitable for implementing the present invention;
[0025] FIG. 2 is a high-level overview diagram of the transferring of data between a local server and a remote client performed in accordance with the present invention;
[0026] FIG. 3 is an architecture diagram of the main components of the present invention;
[0027] FIG. 4 is a flow diagram illustrating the overall logic for running an application in a browser window in accordance with the present invention;
[0028] FIG. 5 is a flow diagram illustrating in detail the logic of running an application;
[0029] FIG. 6 is a flow diagram illustrating in detail the logic of a remote system executing an application;
[0030] FIG. 7 is a flow diagram illustrating in detail the logic of the remote system making a data request;
[0031] FIG. 8 is a message diagram showing the primary data flow between the major components of the present invention;
[0032] FIG. 9 is an exemplary user interface display of the present invention;
[0033] FIG. 10 is an exemplary user interface display shown in response to selection of the Alarm option of the exemplary user interface shown in FIG. 9 ;
[0034] FIG. 11 is an exemplary user interface display shown in response to selection of the History option of the exemplary user interface shown in FIG. 9 ;
[0035] FIG. 12 is an alternative user interface which combines the data shown in FIGS. 9-11 in one user interface display;
[0036] FIG. 13 is an example illustrating two sessions for one client, one HTTP session and one HTTPS session;
[0037] FIG. 14 is an example illustrating two HTTP connections for one client that are funneled through a single session; and
[0038] FIG. 15 is an example of a client with two sessions each with an HTTP connection for a different username/password.
DETAILED DESCRIPTION
[0039] FIG. 1 illustrates a computing environment suitable for implementing the present invention. A remote client computer 100 communicates with a local server computer 200 over a communication medium 118 . For example, the client 100 can communicate with the server 200 over the Internet.
[0040] The remote client computer 100 includes a central processing unit (CPU) 102 . The client 100 also includes memory in the form of random access memory (RAM) 104 and read-only memory (ROM) 106 . The client computer also includes a permanent storage device 108 , such as a hard disk drive.
[0041] The client computer 100 also includes a display device 110 , a keyboard 112 and a pointing device, such as a mouse 114 . In one embodiment of the present invention, the client computer 100 runs a browser program.
[0042] It will be appreciated that many computing environments are suitable for implementing the present invention. For example, the client computer 100 may be a Personal Computer (PC) running various operating systems, for example, Microsoft NT, or various Windows operating systems, as well as other operating systems. It will also be appreciated that the client 100 contains many more components than those illustrated in FIG. 1 , however it is not necessary to show all of theses components in order to disclose an illustrative computing environment suitable for implementing the present invention.
[0043] The server 200 contains similar components as those shown for the client computer 100 . As with the client computer, additional components may be included. For example, the server may an NT Server version 4 or later running Internet Information Server version 4 or later.
IView Client/Server Framework
[0044] FIG. 2 is a high level diagram showing the transferring of data between a remote client 100 and a local server 200 . When data is accessed, the client 100 fills a send request buffer 120 with a data request. After the send request buffer 120 is filled, it is sent to a receive request buffer 220 at the server 200 where the request is read by the server and a send reply buffer 222 is filled with the reply which is sent to the client receive reply buffer 122 where the reply is read by the client. The underlying framework protocol appends the necessary headers on transmission of the respective requests and replies and strips the headers on delivery. The requests/replies events take place in the context of a session, which must first be established before requests/replies are exchanged.
[0045] The Client/Server framework of the present invention, which is known as IView, supports accessing data through the World Wide Web primarily for any client written to the client abstraction application program interface (API). The framework consists of two components: (1) a Data Access Component and (2) a Data Handlers Toolkit.
[0046] A Data Client is a component or program written using the Data Access component. A client establishes a session and starts exchanging requests/replies over that session. The Data Access Component hides all details pertaining to HTTP, Proxies, SSL, and so on. In the particular embodiment described, there are three data clients: a Runtime Data Client, an Alarm Data Client and a History Data Client.
[0047] A particular Runtime Data Client component is the Client Abstraction Layer which is an API that abstracts the communication with input/output (I/O) Servers over Dynamic Data Exchange (DDE) and other custom links that may be present. This layer relies on parameter definitions to choose between DDE and the other custom links. In the instant invention, this layer is augmented by one more protocols (HTTP Tunneling) to support accessing local runtime data over HTTP.
[0048] The Alarm Data Client is an alarm program that uses the service of the Data Access Component directly to gain access to local alarm data over HTTP. The History Data Client is a history program which uses the service of the Data Access Component to gain access to local history data over HTTP.
[0049] In order to process the data accessed, data handlers must be developed. A data handler is a component written using a Data Handler toolkit in order to expose any data to Web clients. There are currently three handlers available which handle the data for the three clients. The existing data handlers are shown in the architecture diagram of FIG. 3 and include:
1. a Runtime Database Handler (RDB) Handler 250 which exposes IOServer or runtime data to any client that uses the Client Abstraction Layer and supports DDE and other protocols; 2. an Alarm Handler 260 which exposes alarm data from the host to the client, as well as any other client that uses the Client Abstraction Layer; and 3. a history Handler 270 which exposes history data from the host to any client that uses the Client Abstraction Layer.
[0053] A typical Data Handler would respond to the following events:
Session creation (client context); Requests via the created sessions; Session deletion; and Session timeout.
[0058] The data handler is run as an NT service. The data handlers receive data requests via an Internet Server Application Program Interface (ISAPI). The data handler retrieves the data from the appropriate I/O server 230 and forwards it to the ISAPI DLL 280 . The ISAPI forwards the data to the appropriate client 100 . The data may be transmitted from the ISAPI 280 to the client 100 via a Web browser 290 over the Internet 150 .
[0059] While the disclosed embodiment contains three data handlers, (runtime database handler alarm handler and history handler), it will be appreciated that other data handlers can be used instead of or in addition to these data handlers.
Flow Logic
[0060] FIGS. 4-7 are flow diagrams illustrating aspects of the logic of the present invention. FIG. 4 is an overall flow diagram of the logic of running a remote client application in a browser. The logic of FIG. 4 moves from a start block to block 500 where a browser is opened on a remote system. The remote system is client computer 100 . Next, in block 502 , a request for a Web page is made using the browser. For example, a hyperlink is selected. The local system, i.e., server 200 , receives the request from the client 100 and transmits the requested Web page to the client for display in the browser. Upon receipt of the Web page, the logic moves to block 506 where the client 100 displays the received Web page. For example, the Web page may be a list of applications that the client can run. The list may be a list of hyperlinks. Next, in block 508 , the client selects an application to run. Finally, in block 510 , the requested application is run as illustrated in detail in FIG. 5 and described next. It will be appreciated that the logic shown in FIG. 4 is standard browser processing. The key feature of FIG. 4 with respect to the present invention is that at some point (block 508 of FIG. 4 ), the remote user selects an application for execution via the Web browser.
[0061] FIG. 5 illustrates in detail the logic of running an application. The application can be run in a browser, as illustrated in FIG. 4 . Alternatively, the application can be run from a command line. The logic of FIG. 5 moves from a start block to block 520 where the system, i.e., server 200 , receives and parses the client request to run an application. The system downloads the requested application to the remote system, i.e., client 100 . See block 522 . Preferably, the application is compressed and downloaded as zip files. Next, in blocks 524 and 526 , respectively, the remote system receives and extracts the application. Next, the remote system executes the application, as shown in detail in FIG. 5 and described next.
[0062] The logic of FIG. 5 of executing an application moves from a start block to block 540 where the remote system makes a data request, as shown in detail in FIG. 7 , and described later. Next, in block 42 , the ISAPI receives and parses the data request. The ISAPI then determines the data handler required to fulfill the data request. See block 544 . The ISAPI then sends the request to the appropriate data handler. The data handler then obtains the node name from the request. The node name specifies the I/O server from which the requested data should be obtained. See block 548 . The data handler then retrieves the data from the node and sends it to the ISAPI. See block 550 . Next, in block 552 , the ISAPI sends the data to the client 100 . Next, in block 554 , the client receives and processes the data. Processing the data includes parsing the data and displaying it. Next, in decision block 556 a test is made to determine if more data is required. If so, the logic returns to block 540 where the remote system makes a data request. If not, the logic of FIG. 6 ends, and processing returns to FIG. 5 . In this manner, data requests are repeatedly processed until termination of the application program.
[0063] FIG. 7 illustrates in detail the logic of making a data request. First, in decision block 560 a test is made to determine whether a secure connection should be used. This information is determined by the application program and is contained in the data request. The data request contains a tag for each piece of data requested. The tag includes an application name, a topic and a node. The present invention uses a special form of node tag designed to run over the Internet. The node tag is of the form: application@<web_server_ip>. Also included in the data request is a handler string which specifies the handler that should be used for obtaining the data, for example, “RDB”, “history” or “alarm”. If a secure connection is to be used, the logic moves to decision block 562 where a test is made to determine whether a secure session already exists. If not, a secure session is established in block 564 . The request is then formatted and transmitted using HTTPS over the existing or newly established secure connection. See blocks 566 and 568 , respectively. If in decision block 560 it is determined that a secure connection should not be used, then a non-secure connection will be used. Accordingly, the logic moves to decision block 570 where a test is made to determine whether a non-secure session already exists. If not, the logic moves to block 572 where a non-secure session is initiated. Next, the logic moves to block 574 where a request is formatted. The formatted request is then transmitted over the existing or newly created non-secure session using HTTP. See block 576 . The logic of FIG. 7 then ends, and processing is returned to FIG. 6 .
[0064] FIG. 8 is a message sequence diagram showing the primary flow of data among the major components of the present invention. A first data request 600 is initiated by the client 100 . The data request is transmitted over the Internet 150 to the Web server 290 . The Web server forwards the data request 602 to the ISAPI 280 , which in turn forwards the request 604 to the appropriate data handler 275 . In the embodiment described herein, the data handler may be a RDB handler 250 , an alarm handler 260 or a history handler 270 . It may also be another data handler. The data handler 275 requests the data 606 from the appropriate I/O server 230 . The requested data 608 is then transmitted from the I/O server 230 to the data handler 275 . The data handler 275 , in turn, forwards the data 610 to the ISAPI 280 . The ISAPI 280 then forwards the data to the client 100 using a new data session. The data session can be a secure data session which uses HTTPS or a non-secure session which uses HTTP.
[0065] A subsequent data request 620 is transmitted from the client 100 to the Web server 290 . The second data request follows the same data path as the first data request. That is, the data request 622 is forwarded from the Web server 290 to the ISAPI 280 . The data request 624 is then forwarded from the ISAPI 280 to the appropriate data handler 275 . The data request 626 is then forwarded from the data handler 275 to the I/O server 230 . The I/O server 230 sends the requested data 628 to the data handler 275 . The data handler 275 then sends the data 630 to the ISAPI 280 . The ISAPI 280 determines whether there is an existing session of the required type (i.e., secure or non-secure) over which the data can be transmitted. If there is an existing session of the proper type, the data 632 is transmitted to the client 100 using the existing session. If there is no existing session of the proper type, the data 632 is transmitted to the client 100 using a new session. Performance is boosted by using existing sessions rather than creating new sessions. Existing sessions can be shared by multiple data handlers. For example, the ISAPI 280 can send data from an RDB handler 250 , an alarm handler 260 and a history handler 270 to a given client 100 using a single session.
AN ILLUSTRATED EXAMPLE
[0066] FIGS. 9-12 illustrate exemplary user interfaces displayed on the client's display 110 . As described earlier, the user interface may appear in a browser window or in its own application window. FIG. 9 illustrates a user interface which includes runtime data 700 which is provided by the runtime database handler. Also included are an Alarm button 702 and a History button 704 . If the user depresses the Alarm button 702 , the Alarm display shown in FIG. 10 is displayed. The Alarm display shows alarm data 710 provided by the Alarm handler. If the History button 704 is depressed, the History display shown in FIG. 11 is displayed. The History display shows displays historical data 720 provided by the History handler.
[0067] FIG. 12 illustrates an alternative user interface to the user interface shown in FIGS. 9-11 . The user interface shown in FIG. 12 displays the runtime data 700 , the alarm data 710 and the history data 720 in a single window.
HTTP Tunneling Protocol
[0068] A special data client component is the Client Abstraction Layer which is an API that abstracts the communication with I/O Servers over DDE and SuiteLink. This layer relies on parameters to choose between DDE and SuiteLink. For the IView, this layer is augmented by one more protocol (IView HTTP Tunneling) to support accessing runtime data over HTTP.
[0069] The protocol is an abstraction over HTTP and allows a client to establish a session with a specific handler. A handler is identified by the form, {URI, HandlerName} where the URI (Uniform Resource Indicator) IS of the form “http[s]://[user][password]:server[port]” with the parameters in square brackets being optional. The first parameter, “s,” signifies whether or not this connection will be using SSL. The user and password parameters work together and allow for server side authentication of the client using standard Windows NT security. The server parameter can either be the machine's Internet Protocol (IP) address or its fully qualified domain name, such as, “www.mycompany.com.” The last parameter, “port,” tells the client which port to connect to on the server with the default being “80,” the standard for HTTP connections.
[0070] The session serves as a context identifier between the handlers and client. For the handlers, the session id is the client context. A client may establish as many sessions as it needs. Sessions are determined based on the specific data sought. The data fields at the local server contain property definitions which define the type of session to be used. The session API allows the user to specify extra information for the requests/replies that could be used for dispatching purposes.
[0071] For example, as shown in FIG. 13 , a client 100 using the Client Abstraction Layer could make a connection using HTTP 180 for a few data points. That same client could then make another connection for other data points using HTTPS 182 . This client would then have two sessions, as well as two connections. The second session is established because the method of connection has changed from HTTP to HTTPS as defined by the data properties.
[0072] In another example, shown in FIG. 14 , a client 100 makes a connection using an HTTP to server A for a set of data points. The client then makes a second HTTP connection to server B for a second set of data points. This client has two HTTP connections, which are funneled through one session.
[0073] In a third example, shown in FIG. 15 , a client 100 makes an HTTP connection for a set of data points that requires a username and password. The client then makes a second HTTP connection for another set of data points that requires a different username and password. This client then has two sessions and two HTTP connections.
[0074] The Data Access component establishes one or more HTTP connections to serve the sessions. The Data Access Component abstracts the details of HTTP connections from the session. Fault tolerance is built in to allow the sessions not to be aware that an HTTP connection was lost and another one was established. From the standpoint of clients and handlers, requests are sent and replies are received in the form of buffers, as shown in FIG. 2 .
[0075] From the framework standpoint, the Data Access Component established HTTP connections to a Web server. Requests received by the web server are delegated to an ISAPI which dispatches the requests to the correct handler and then forwards the replies back to the clients. The Data Access Component serializes the client requests into packets and prepends a header used later by the ISAPI in order to dispatch the requests to the correct handler. By the same token, the ISAPI serializes the replies and prepends a header for proper dispatching to the correct session. The data access component uses polling in order to send requests and receive replies. Session requests are queued and then on the next polling interval everything is sent and the replies to previous requests are picked up.
[0076] This invention allows existing client applications to run in the context of an Internet Browser without modification by the original developer. In fact, the client applications can be made to execute in any context that can host an ActiveX control. This has been accomplished by modifying the local runtime application, which in the specific embodiment is a window viewer (view.exe), to become a local server and to provide an ActiveX control object to host the server. Normally the local window viewer is launched via an icon on the desktop or through the command line. Once modified to be a local server, the window viewer can be launched via techniques well known to COM and Distributed Component Object Model (DC OM) programmers. Thus, the instant invention provides a general technique for allowing desktop bound applications to be available over the Internet. This permits the remote system desktop bound application to send and receive data to and from a local site on the Internet.
Local Server Support:
[0077] This invention involves the creation of a library called VIEWLS.LIB that is linked to the existing local legacy code base. The purpose of this library is twofold: (1) to provide an implementation for local server services; and (2) to provide an IDispatch based interface for interaction with the ActiveX control. Local servers are required to support three command line switches: (1) /RegServer, (2) IUnregServer, and (3) /Embedding. The legacy code has been modified to look for each of these switches and to call into this new library for proper handling if any of these switches are found.
[0078] The implementation of “/Reg Server” results in registry entries being created. These entries are sufficient for COM to locate and launch the local server. The implementation of “lUnregServer” removes the registry entries created by “/RegServer.” The implementation of “/Embedding” results in the registration of the class object. COM requires a class object in order to create an instance of the COM object. In the case of “/Embedding” the local legacy code has been modified to bypass its normal initialization sequence. Instead, the host ActiveX control will call a method in the IDispatch based interface to do the initialization.
[0079] The IDispatch based interface, identified by lID-DIViewLS, provides methods for manipulating the legacy code. The methods in this interface are as follows:
[0080] SetApplicationDirectory: This method accepts the path that defines the directory for the client application. WindowViewer has a feature that allows it to run any client application that appears on the command line. If no such directory is present, it defaults to the last known client application. The argument to the method is used to create a command line that is handed off to WindowViewer. The WindowViewer, when run in the context of the Internet Browser is not constrained to use the application that would load if it had been run from the desktop. The “normal” behavior for WindowViewer is to run the application that has been specified on the command line. If no application appears there, WindowViewer will read some initialization (0.00) file settings to determine which application to launch. The .OO file settings keep track of the last application run. The present invention makes use of this feature and adds the application selected off of the Web page to the command line of the local server. Thus, the Web page is able to launch any application that has been downloaded to the computer without requiring extensive changes to WindowViewer. An additional benefit is that the desktop user's last application is not changed because WindowViewer, when running as a local server, does not modify these settings.
[0081] SetIP Address: This method accepts the IP Address for the local server. This parameter is then used in the legacy, i.e., existing, code to provide an ambient property in the ActiveX control container. This property allows controls that have been made aware of the property to gain access to the local server's IP Address. The mechanism that the ActiveX control uses to define the values used in the connection call include this method, as well as the SetUser and SetPassword methods.
[0082] SetUser: This method accepts the user name for the local server. This parameter is then used in the legacy code to provide an ambient property in the ActiveX control container. This property allows controls that know about it to gain access to the appropriate user name.
[0083] SetPassword: This method accepts the password for the user specified in the SetUser method. This method is then used in the legacy code to provide an ambient property in the ActiveX control container. This property allows controls that know about it to gain access to the appropriate password.
[0084] CreateServerWnd: This method allows another path into the initialization sequence for WindowViewer. If the “/Embedding” command line argument is present, the normal initialization sequence will be bypassed, If this happens, WindowViewer will not be initialized and will be unable to operate correctly. The expectation is that the hosting ActiveX control, which is part of this invention, will call this method. The implementation of this method fully initializes WindowViewer and creates the main window of the application by calling existing initialization functions in the legacy code. This method should not be called until all parameters are correctly defined. This allows the Web page to initialize the ActiveX control before continuing the initialization of the local server. The parameters to this method include size, position, window style, and parent handle. The handle of the created window, which is the main application window of WindowViewer, is returned via another parameter. Thus, the controlling ActiveX control has access to the main application window created by the local server.
[0085] GetWindowList: This method retrieves all the windows that are in the client application by name. The parameters to this method are used to return the created selection list and a count of the items on that list.
[0086] Release WindowList: This method releases all windows retrieved by GetWindowList. The parameter to this method is the selection list.
[0087] Get WindowNameAndIndex: This method retrieves information specific to a window. The input parameters to this method are the selection list and sequence index. Two output parameters return the string name of the window and the window index, which is different from the sequence index.
[0088] The Interface Definition Language (IDL) for this interface is set forth below: [object, oleautomation, dual, uuid(C8947A20-E9CD-lldl-BI58-00AOC95AC277)]
[0000]
interface DIViewLS : IDispatch
{
[helpstring( “Set Application Directory” )]
HRESULT SetApplicationDirectory( [in] BSTR
szApplicationDirectory);
[helpstring( “Set IP Address” )]
HRESULT SetIPAddress( [in] BSTR szIPAddress);
[helpstring( “Set User” )]
HRESULT SetUser( [in] BSTR szUser );
[helpstring( “Set Password” )]
HRESULT SetPassword( [in] BSTR szPassword );
[helpstring( “Create Server Window” )] HRESULT
CreateServerWnd
(
[in] LONG Size_cx,
[in] LONG Size_cy,
[in] LONG Pos_cx,
[in] LONG Pos_cy,
[in] ULONG Style,
[in] ULONG hwndParent,
[in] ULONG id,
[out] ULONG* phwnd
);
[helpstring( “Get list of windows within the application”)]
HRESULT GetWindowList
(
[out] ULONG* p WindowList,
[out] ULONG* pCount
);
[helpstring( “Release list of windows within the application” )]
HRESULT ReleaseWindowList( [in] ULONG WindowList);
[helpstring( “Get name of specific window within the
application” )]
HRESULT GetWindowNameAndlndex
(
[in] ULONG WindowList,
[in] ULONG Sequencelndex,
[out] BSTR* pWindowName,
[out] ULONG* pWindowlndex
);
};
[0089] The local runtime code is made capable of determining whether it is running as a desktop application or in the context of the associated ActiveX control by the introduction of a global variable that contains the application directory, user name, password, a flag to indicate whether or not it is running as a local server, size, position, style, parent handle, id, and main window handle. At any point in the legacy code where behavior in the browser should differ from behavior of a desktop application this global variable is consulted to determine the execution context.
[0090] Thus, when running in the context of a local server, the startup code displaying the splash screen is omitted and code that sets the style for the main window is omitted. (The style is set by the controlling ActiveX control via the CreateServerWnd method.) Therefore, when the WindowViewer runs in the context of an Internet Browser, no trace is left behind.
[0091] Two new command messages are included in the main window procedure for WindowViewer that allow various windows to be loaded and unloaded. The single parameter to these new command messages is a window index. This index is cached by the ActiveX control and was obtained through the use of the method GetWindowNameAndIndex which is exposed by the local server.
[0092] Command line processing was modified to look for “/RegServer”, “lUnregServer”, and “!Embedding”. When any of these switches is found it calls into a function provided by VIEWLS.LIB to provide the implementation.
ActiveX Control:
[0093] Another new feature of this invention is a particular ActiveX control, VIEWCTLOCX that serves as the context for execution. Essentially any program that can host an ActiveX control, for example, an Internet Browser, VB, etc., can be a WindowViewer host. The hosting program creates an instance of VIEWCTLOCX and when created it causes an instance of the local server to be created. Once the local server is created, the OCX call, CreateServerWnd method, is exposed by the local server. It takes the resulting window handle and makes it a child of the OCX. This results in the local server's window reacting to the things that happen to the screen area associated with the OCX. For example, if the OCX is minimized, the server window is also minimized. If the OCX is moved, the server window is also moved. When the OCX is closed, the server window is also closed.
[0094] The user interface presented by the OCX allows the remote user to show and hide windows as desired. If the application has been created with its own internal window management, the OCX can be configured to not show the browser navigation frame. Once the user has selected and displayed a window, the user interacts with the window as if it were on the remote desktop.
[0095] The IDispatch based interface, identified by lID-DIViewLS, provides the methods for manipulating the legacy code. The properties in this interface are as follows:
[0096] GetWindowSets: This property returns an enumerator for windows that are part of the client application.
[0097] NavigationFrame: This property determines whether or not the ActiveX control displays a frame filled with window names on the left side of the display. This is a useful feature when the client application does not provide any navigation mechanism. If the frame is enabled, it can be reduced in size because it is based on splitter window technology.
[0098] The methods in this interface are as follows:
[0099] ShowWindow: The parameter to this method is the name of the window. The implementation will send a command message to the local server window, which results in the window being loaded and displayed.
[0100] HideWindow: The parameter to this method is the name of the window. The implementation will send a command message to the local server window, which results in the window being hidden.
[0101] SetApplicationDirectory: The parameter to this method is the path to the client application. The implementation will call into the local server to set the value in the global variable introduced by VIEWLS.LIB.
[0102] Create Server Window: There are no parameters to this method. The implementation results in a call into the local server to create the main window for WindowViewer and to fully initialize it.
[0103] SetIP Address: The parameter to this method is the IP Address for the machine. The implementation calls into the local server to set this value.
[0104] SetUser: The parameter to this method is the user id to be used. The implementation calls into the local server to set this value.
[0105] SetPassword: The parameter to this method is the password for the specified user. The implementation calls into the local server to set this value.
[0106] The IDL for this interface is set forth below:
[0000]
[ uuid(BFB5EDD4-E9DA-IIDI-BI58-00AOC95AC277),
helpstring(“Dispatch interface for IView Control”), hidden]
dispinterface_DIView
{
properties:
// NOTE - Class Wizard will maintain property information here.
// Use extreme caution when editing this section.
//{{AFX_ODL_PROP(CIViewCtrl)
[id(1)] V ARrANT GetWindowSets;
[id(2)] Boolean NavigationFrame;
//}}AFX_ODL_PROP
methods:
// NOTE - Class Wizard will maintain method information here.
// Use extreme caution when editing this section.
//{{AFX_ODL_METHOD(CIViewCtrl)
[id(3)] void ShowWindow(BSTR szWindowName);
[id(4)] void HideWindow(BSTR szWindowName);
[id(5)] void SetApplicationDirectory(BSTR szApplicationDirectory);
[id(6)] void CreateServerWindowO;
[id(7)] void SetIP Address(BSTR szIP Address);
[id(8)] void SetUser(BSTR szUser);
[id(9)] void SetPassword(BSTR szPassword);
//}}AFX_ODL_METHOD
[id(DISPID_ABOUTBOX)] void AboutBoxO;
};
Handler Toolkit
[0107] The IView Handler Toolkit provides an easy way for users to develop their own handlers for a specific data type. The toolkit contains an abstract class that contains the functions needed to implement a handler. That class sits above a class defining the NT service functionality. An example of a handler created. using the handler toolkit is set forth below:
[0000]
(1) class TestHandlerListener : public OutpostHandlerActionListener
{
bool m - bDone;
bool m - bPause;
DWORD m_dwThreadID;
public:
bool OnInit( ){
m - bDone = false;
m - bPause = false;
m_dwThreadID = 0;
return true;
}
(2) void Run(int argc,char* argvO) {
MSG msg;
m - dwThreadID = GetCurrentThreadId( );
while (m_bDone = false) {
while (::PeekMessage(&msg, NULL, 0, 0, PM_REMOVE)) {
// get next message in queue
if(WM _QUIT = msg.message) {
m_bDone = TRUE;
Beep(400,400);
Beep(400,400);
Beep(400,400);
break;
}
::TranslateMessage(&msg);
::DispatchMessage(&msg);
}
}
printf(“\nEnd Run threadld = %d\n,” GetCurrentThreadld( ));
}
(3) void OnStop( ) {
m_bDone = true;
}
(3) void OnInterrogate( ) { }
(3) void OnPause( ) {
m_bPause = true;
}
(3) void OnContinue( ) {
m_bPause = false;
}
(3) void OnShutdown( ) {
m_bDone = true;
}
(3) bool OnUserControl(DWORD dwOpcode) {
return true;
}
(4) unsigned long OnData(unsigned long uniqueSessionID,
long IRequestSize,
unsigned char *pRequestData,
long *IReplySize,
unsigned char **ppReplyData)
{
printf(“OnData uniqueSessionID = %d\n,” uniqueSessionID);
printf(“\t\tRequestSize = %d\n,” IRequestSize);
printf(“%s\n,” pRequestData);
*IReplySize = IRequestSize;
*ppReplyData =(unsigned char*)
OutpostHandler::AllocateMemory(lRequestSize);
if(*ppReplyData)
memcpy(*ppReplyData, pRequestData, IRequestSize);
else
printf(“Memory Error\n”);
return 0;
}
(5) unsigned long OnCreateSession(unsigned long uniqueSessionID) {
printf(“OnCreateSession uniqueSessionID = %d\n,”
uniqueSessionID);
return 0;
}
(6) unsigned long OnCloseSession(unsigned long uniqueSessionID) {
printf(“OnCloseSession uniqueSessionID = %d\n,”
uniqueSessionID);
return 0;
}
};
In the handler's main method, the object is created and initialized as follows:
(7) TestHandlerListener *pTestHandlerListener =
new TestHandlerListenerO;
(8) OutpostHandler *pHandler=new OutpostHandler( );
if (!pHandler->Init(argc, argv,
p T estHandlerListener,
handler, handler))
printf(“pHandler-> Init Failed\n”);
[0108] The toolkit also allows for easy development of clients by users. Below is a class illustrating client functionality:
[0000]
class EchoListener : public IOutpostSessionListener
{
public:
bool OKToSend;
(9) EchoListener( ) { OKToSend = false; };
void SessionCreated(DWORD dwSessionID) {
cout << “SessionCreated(“ << dwSessionID << ”)”
<< endl;
OKToSend = true;
}
(10) void SessionCreateFail(DWORD dwErrorCode) {
printf( “SessionCreateFail( dwErrorCode = %ld
[Ox%08x])\n,” dwErrorCode, dwErrorCode);
}
(11) void SessionClosed(DWORD dwSessionID) {
cout <<“SessionClosed(“ <<dwSessionID <<”)” <<endl;
}
(12) void Receive(DWORD dwSessionID,
LPVOID IpBuf,
DWORD dwSize,
DWORD dwRequestID,
DWORD dwSenderID) {
printf( “Data: %. *s\n,” dwSize, IpBuf);
OKToSend = true;
}
(13) void SendFail(DWORD dwSessionID,
DWORD dwReason,
DWORD dwRequestID,
DWORD dwSenderID ) {
printf( “SendFail(RequestID:%d,Sender ID:%d) \n,”
dwRequestID, dwSenderID );
}
(14) void SendSucceed(DWORD dwSessionID,
DWORD dwRequestID,
DWORD dwSenderID) {
printf( “SendSucceed(RequestID:%d,SenderID:%d)\n,”
dwRequestID, dwSenderID );
}
(15) void SessionError(DWORD dwErrorCode, char
szErrorCode[128]) {
printf( “SessionError( ErrorCode = Ox%08x,
szErrorCode:%.*s)\n,” dwErrorCode, 128, szErrorCode );
}
};
[0109] In the client, objects similar to the handler are used to open a session such as shown below:
[0000]
EchoListener *pEchoListener = new EchoListener( );
IOutpostSession *pSession = new IoutpostSession( );
bool rc = pSession->Open(outpost, handler, pEchoListener);
if (rc == false)
cout << “pSession->Open Failed” << endl;
The loop set forth below starts the polling for data:
for ( size_t requestID=1, senderID=200; rc==true;) {
if ( pEchoListener->OKToSend == true) {
char szWord[4096] = {0}; cout<< “Enter string: ” ;
if( 0 == gets(szWord) ∥ 0 == szWord[0])
break;
pSession->Send(szWord, strlen(szWord) + 1,
requestID, senderID);
pEchoListener->OKToSend = false;
requestID++, senderID++;
}
Sleep(500);
}
[0110] Where
[0111] (1) is the abstract class needed to implement a handler;
[0112] (2) is the run method which starts the handler's thread;
[0113] (3) are six functions that correspond to the needs of a service;
[0114] (4) is a function that handles the request/reply;
[0115] (5) creates the session given a unique id passed from the client;
[0116] (6) closes the session corresponding to the id passed from the client;
[0117] (7) is the user's handler object;
[0118] (8) is the handler object provided by the toolkit;
[0119] (9) notifies the client that a session has been created;
[0120] (10) notifies the client that a session creation failed;
[0121] (11) notifies the client that a session has been closed;
[0122] (12) handles the data coming from the server;
[0123] (13) provides error information for a failed send;
[0124] (14) notifies the client that the send was successful; and
[0125] (15) provides error code information for session errors.
[0126] While a specific embodiment of this invention has been described above, those skilled in the art will readily appreciate that many modifications are possible in the specific embodiment, without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention, as defined in the following claims. | A system and method for remote control including a control system having a memory and a CPU for sending and receiving control information and instructions at a first location, a software application for manipulating the control information sent and received by the control system resident in the memory, a remote computer system having a CPU and memory at a second location communicating over a communication path with the control system at the first location and one desktop bound software application for manipulating the control information sent and received by the control system accessed by the remote computer system over the at least one communication path resident in the memory of the remote computer system. In variations, the control information includes alarm data, runtime data and historical data. | 7 |
RELATED APPLICATIONS
The present application is a continuation of application Ser. No. 10/807,368, filed on Mar. 22, 2004, which is a continuation of application Ser. No. 10/218,475, filed on Aug. 12, 2002, now issued as U.S. Pat. No. 6,752,756, which is a continuation of application Ser. No. 09/490,552, filed Jan. 25, 2000, and now issued as U.S. Pat. No. 6,432,044, which is a continuation of Ser. No. 09/227,393, filed Jan. 8, 1999, now abandoned, which is a continuation-in-part application of application Ser. No. 09/102,723 filed on Jun. 22, 1998, now issued as U.S. Pat. No. 5,895,353 and the subject matter hereof is related to the subject matter of application Ser. No. 08/593,533 entitled “Tissue Separation Cannula” filed on Jan. 24, 1996 by Albert K. Chin, now abandoned, which is a continuation-in-part application of application Ser. No. 08/502,494, entitled “Tissue Separation Cannula And Method,” filed on Jul. 13, 1995, now abandoned, which prior applications are assigned to the same assignee as the present application and are incorporated herein in their entireties by this reference thereto.
FIELD OF THE INVENTION
This invention relates to a cannula used for vessel retraction, and more particularly to a cannula and method for retracting a vessel during dissection and transection.
BACKGROUND OF THE INVENTION
One important component of a surgical cannula is the tip, disposed on the distal end of the cannula. A properly configured tip can provide important functionality to a cannula. For example, the functions of vessel dissection and transection are commonly performed by two separate instruments. The device described in the pending application Ser. No. 08/907,691, entitled “Tissue Separation Cannula with Dissection Probe and Method,” filed on Aug. 8, 1997, discloses a device for separating surrounding connective tissue from a vessel (dissection). The device described in the pending application Ser. No. 09/102,723, entitled Vessel Isolating Retractor Cannula and Method,” filed on Jun. 22, 1998, discloses a device for retracting the vessel, ligating side branches, and transecting the branches to allow removal of the vessel. It is desirable to use a single device for performing the above functions.
The construction of a cannula tip also affects the visual field provided to a surgeon through an endoscope. When an endoscope is situated in a lumen of the cannula, the surgeon looks through the endoscope and through the transparent tip to view the surgical site. It is desirable to have a tip which maximizes the visual field of the endoscope.
The cannula tip may also be used to dilate a tunnel or anatomical space through tissue planes. In pending application Ser. No. 09/133,136, entitled “TISSUE DISSECTOR APPARATUS AND METHOD,” filed Aug. 12, 1998, assigned to the same assignee as the present application, and which is hereby incorporated by reference, a cannula is constructed with a bulbous element near the tip of the cannula for performing tissue dilation as the cannula is advanced. Cannula tips for dilating tunnels through tissue require force in order to advance the cannula and dilate the tissue. It is desirable to have a tip which can perform tissue dilation or dissection using a minimal amount of force and causing minimal trauma.
SUMMARY OF THE INVENTION
In accordance with the present invention, a tissue retractor is positioned within a cannula with a dissection cradle end of the retractor positioned at the distal end of the cannula. The retractor includes a first portion that has an axis approximately parallel to a central axis of the cannula, and a second portion that has an axis which is at an angle with respect to the central axis of the cannula. The dissection cradle is located at the distal end of the second portion of the retractor. In another embodiment, the retractor includes two legs having substantially parallel axes that selectively protrude from the distal end of the cannula. The protruding legs support the dissection cradle formed in the shape of a loop that is positioned in a plane skewed relative to the axes of the legs, with a bottom of the loop directed away from the cannula. Thus, in operation, when the surgeon locates a vein and side branch of interest, the surgeon extends the retractor to cradle the vein in the dissection cradle. Once cradled, the retractor may be fully extended to urge the vein away from the axis of the cannula, causing the side branch to be isolated and exposed to a surgical tool. The surgical tool may then be extended from within the cannula to operate on the isolated and exposed side branch.
In another embodiment, the top of the loop of the dissection cradle is flat and thin, allowing atraumatic support of the vein, and minimizing contact between the retractor and the surgical tool. In yet a further embodiment, the retractor includes a single leg with the loop formed by the one leg of the retractor, and with a stopper coupled to the distal end of the retractor. In still another embodiment, the cannula comprises a sliding tube which encases the retractor, and in a first position is extended out to encase the second portion of the retractor, and in a second position is extended to encase only the first portion of the retractor. In response to the sliding tube being in the first position, the second and first portions of the retractor are both approximately parallel to the axis of the cannula. In response to the sliding tube being in the second position, the second portion of the retractor is skewed relative to the axis of the cannula.
In accordance with an alternate embodiment of the present invention, a removable, transparent tip is positioned at the distal end of the cannula to provide a single cannula for performing dissection and transection. When attached, the tip seals the distal end of the cannula in a fluid resistant manner. The tip is conical and ends in a sharp interior point and a slightly rounded exterior point which allows the surgeon to bluntly dissect tissue in the area of interest under endoscopic visualization. When tissue dissection is complete, the surgeon can remove the tip from the cannula, and the surgeon is now able to use the cannula to transect side branches and vessel ends. In order to maximize the visual field provided by the endoscope, the tip is configured to allow the apex of the tip to be aligned with the central axis of the endoscope. In one embodiment, a distal end of the tip is tilted in an oblique fashion to allow the apex of the tip to align with or near to the central axis of the endoscope. In an alternate embodiment, the conical end of the tip has unequal taper angles relative to a plane of transition between the cylindrical and conical portions of the tip, thus skewing the position of the apex of the tip into alignment with or near to the central axis of the endoscope.
In another embodiment, wing-like protrusions are provided about the cannula near the tip to dilate tissue surrounding the vessel of interest. In one embodiment, the wing-like protrusions are diametrically aligned in a planar configuration with tapered forward edges extending rearward from near the apex of the tip. The planar configuration of the wing-like dilating protrusions near the tip substantially reduces the resistive force encountered during advancement of the cannula through tissue. The wing-like protrusions are positioned on opposite sides of the tip to dissect tissue to form a cavity that may attain a round cross-section under insufflation, thus providing the same resultant tissue dilation as provided by a solid oval dilator, but with less force required to accomplish the tissue dilation. In an alternate embodiment, the leading edges of the wing-like protrusions are curved in a parabolic configuration away from the distal end of the cannula to provide the necessary dilation.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a preferred embodiment of cannula 100 showing retractor 112 in an extended position.
FIG. 2 a is a cut-away side view of retractor 112 and cannula 100 .
FIG. 2 b is a top view of retractor 112 .
FIG. 3 a is a perspective side view of cannula 100 with a sapphenous vein positioned within the cradle 116 .
FIG. 3 b is a perspective side view of the distal end 122 of cannula 100 in an embodiment in which an endoscope 126 and a surgical tool 120 are present and partially extended.
FIG. 3 c is a front view of the distal end 122 of cannula 100 in which the surgical tool 120 and the retractor 116 are partially extended, and an endoscope 126 is present.
FIG. 4 a is a cut-away top view of cannula 100 .
FIG. 4 b is a cut-away side view of cannula 100 .
FIG. 5 a is a cut-away view of a sliding tube embodiment of cannula 100 in a first position.
FIG. 5 b is a cut-away view of the sliding tube embodiment of FIG. 5 a in a second position.
FIG. 6 a is a cut-away view of an embodiment of cannula 100 having an angling device 140 .
FIG. 6 b is a cut-away side view of the apparatus illustrated in FIG. 6 a in which the retractor 112 is extended and the angling device 140 is actuated.
FIG. 6 c is a cut-away side view of the angling device embodiment in which the angling device 140 is in a separate lumen from the retractor 112 .
FIG. 7 a is a cut-away side view of a twistable retractor 112 in a straight position.
FIG. 7 b is a side view of the retractor 112 of FIG. 7 a.
FIG. 7 c is a cut-away side view of twistable retractor 112 in a crossed position.
FIG. 7 d is a side view of the retractor 112 of FIG. 7 c.
FIG. 8 a is a cut-away side view of the handle 104 .
FIG. 8 b is a cut-away side view of an alternate embodiment of handle 104 .
FIG. 9 a is a side view of cradle 116 .
FIG. 9 b illustrates a first alternate embodiment of cradle 116 .
FIG. 9 c illustrates multiple views of a second alternate embodiment of cradle 116 .
FIG. 9 d illustrates multiple views of a third alternate embodiment of cradle 116 .
FIG. 9 e illustrates multiple views of a fourth alternate embodiment of cradle 116 .
FIG. 9 f illustrates multiple views of a fifth alternate embodiment of cradle 116 .
FIG. 9 g illustrates multiple views of an embodiment of cradle 116 having a spur.
FIG. 10 a illustrates a top view of an embodiment of the cradle 116 of FIG. 9 c without a “C” ring.
FIG. 10 b illustrates a side view of the cradle 116 of FIG. 10 a.
FIG. 10 c illustrates a top view of the cradle 116 of FIG. 9 c with the “C” ring attached.
FIG. 10 d illustrates a side view of the cradle 116 of FIG. 10 c.
FIG. 11 a illustrates a cut-away side view of a tip 1100 in a cannula housing an endoscope 126 .
FIG. 11 b illustrates a side view of the tip 1100 isolated from cannula 100 .
FIG. 12 a illustrates a side view of an offset tip 1200 in accordance with the present invention.
FIG. 12 b illustrates a cut-away side view of the offset tip 1200 in a cannula 100 housing an endoscope 126 .
FIG. 12 c illustrates a cut-away side view of an alternate embodiment of offset tip 1200 .
FIG. 13 illustrates a cut-away side view of an alternate embodiment of the offset tip 1300 .
FIG. 14 a illustrates a perspective side view of the offset tip 1200 and mounting rod 1404 .
FIG. 14 b illustrates a perspective side view of cannula 100 for housing offset tip 1200 and mounting rod 1404 .
FIG. 14 c illustrates a perspective side view of offset tip housing 1424 at the proximal end of the cannula 100 .
FIG. 14 d illustrates a perspective side view of cannula 100 with offset tip 1200 and offset tip housing 1424 .
FIG. 14 e illustrates a perspective side view of an alternate embodiment of offset tip mount 1424 .
FIG. 14 f illustrates a cut-away side view of the offset tip mounting 1424 of FIG. 14 e.
FIG. 15 a illustrates a side view of an alternate embodiment of offset tip 1200 .
FIG. 15 b illustrates a side view of a cannula 100 modified for use with the offset tip 1200 of FIG. 15 a.
FIG. 16 is a flow chart illustrating a method of dissecting and transecting vessels according to the present invention.
FIG. 17 a illustrates a top view of an embodiment of an offset tip dilator 1700 according to the present invention.
FIG. 17 b illustrates a side view of the embodiment of offset tip dilator 1716 of FIG. 17 a.
FIG. 17 c illustrates a top view of an alternate embodiment of offset tip dilator 1700 .
FIG. 18 is a flow chart illustrating a method of dilating tissue in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 illustrates a perspective view of a preferred embodiment of cannula 100 showing retractor 112 in an extended position. Cannula 100 includes an outer housing 102 of bioinert material such as polymed UD that may be approximately 12″ to 18″ in length. The proximal end of the cannula 100 is disposed in handle 104 that includes a button 106 which is coupled to retractor 112 for controlling the translational movement of retractor 112 , as described in more detail below.
The distal end of the cannula houses a retractor 112 , and optionally an endoscope 126 and a surgical tool 120 , described below. FIG. 2 a illustrates the retractor 112 in more detail. In one embodiment, retractor 112 is formed of resilient wire which has a smooth bend intermediate to a first portion 110 and a second portion 114 of the retractor. The retractor 112 is described as having two portions for ease of description, although the retractor 112 may be formed as an integrated structure. However, retractor 112 may also be manufactured from two separate portions 110 , 114 that are coupled together. The first portion 110 of the retractor 112 is positioned within the cannula 100 with the axis 111 of the first portion 110 approximately parallel to the axis 101 of the cannula 100 . The second portion 114 is positioned to bend away from the central axis 101 of the cannula. The angle 117 of displacement between the axis 115 of the second portion and the central axis 101 of cannula 100 may be any angle from zero to 180 degrees. The second portion 114 includes a dissection cradle 116 at the distal end of the second portion 114 . The retractor 112 may be formed of bioinert material such as stainless steel, or a polymer such as nylon or polyetherimide, or other appropriately strong and resilient plastic. In one embodiment, the retractor 112 includes a coating for lubrication, insulation, and low visual glare using, for example, parylene or nylon 11.
FIG. 2 b illustrates the retractor 112 formed with two legs. The legs 141 , 142 of the retractor 112 at the distal end form the dissection cradle 116 in a loop or “U” shape, as shown in FIG. 2 a . The top portion 144 of the U-shaped bend is preferably flattened to provide additional surface area for atraumatically supporting a vein 118 or vessel of interest. The side arches 128 of the dissection cradle 116 are used for skeletonizing or dissecting the vein from the surrounding tissues, as well as acting as walls to keep the vessel captured within the arch. The several embodiments of dissection cradle 116 are described in more detail below.
FIG. 3 a illustrates a perspective view of the cannula 100 in accordance with the present invention with the retractor fully extended, holding a sapphenous vein 118 , and also illustrates an external surgical tool 120 disposed adjacent the cannula 100 for performing a surgical operation, for example, severing a tributary or side branch of the vein 118 . The vein is positioned within the side arches 128 of the cradle 116 . The dissection cradle 116 may be used to cradle a vein, vessel, tissue or organ of interest, and surgical tool 120 may be any surgical tool suitable for performing a surgical procedure near the dissection cradle 116 .
FIG. 3 b illustrates a perspective view of cannula 100 in an embodiment in which the surgical tool 120 is positioned within the cannula 100 , and an endoscope 126 is present. In this embodiment, cradle 116 preferably overlays the endoscope 126 with sufficient clearance to facilitate relative movements thereof. However, the endoscope may also be located adjacent the surgical tool 120 . In one embodiment, endoscope 126 is positioned with cannula 100 to allow a clear field of view upon extension of the retractor 112 . Surgical tool 120 is illustrated as cauterizing scissors, used to sever a tributary or side branch of a sapphenous vein 118 . In this embodiment, surgical tool 120 is maximally displaced from the cradle 116 at the cannula end 122 . More specifically, as shown in FIG. 3 c , the “U”-shaped loop 129 of the cradle 116 is closest to the surgical tool 120 . This ensures that a vein 118 or other tissue of interest is retracted away from the surgical tool 120 to facilitate manipulating the surgical tool 120 relative to the side branch or other tissue.
FIG. 4 a is a cut-away top view of cannula 100 . The retractor 112 is slidably positioned within minor lumens 113 along the length of the cannula 100 within close tolerances in order to position the retractor 112 stably within the cannula 100 . For example, in one embodiment retractor legs 141 , 142 are approximately 0.045 inches in diameter and the lumens 113 encasing the legs 141 , 142 are approximately 0.080 inches in diameter, as friction between the legs of the retractor 112 and the lumens 113 holds the retractor stably within the cannula. This configuration restricts rotational movement of the retractor to provide more stable retraction as compared with conventional retractors. The legs 141 , 142 of the retractor 112 are formed of flexible, resilient material and are retained within the lumen 113 in substantially straight or flat orientation, but may return to a material bend or curve, as illustrated in FIG. 5 a , as the retractor 112 is extended from the distal end of the cannula 100 .
The leg 141 of the retractor 112 passes through a sliding gas or fluid seal 130 at the proximal end of the lumen 113 . The leg 141 of the retractor 112 passes out of the cannula 100 and into handle 104 for attachment to a slider button 106 for facilitating translational movement of the retractor 112 from the proximal or handle end of the cannula 100 . However, other types of control devices such as knobs, grips, finger pads, and the like may be linked in conventional ways to the retractor 112 in order to manually control the translational movement of retractor 112 . In one configuration, the proximal end of leg 141 is bent relative to the axis of the cannula, and the button 106 is attached to the bent position of the leg 141 to facilitate moving the button 106 and the retractor 112 translationally under manual control. The button 106 preferably includes lateral grooves to prevent finger or thumb slippage during sliding manipulation of the retractor 112 .
Thus, in the operation of a preferred embodiment, a user actuates the slider button 106 to extend retractor 112 out of the lumen 113 at the distal end of the cannula 100 . In one embodiment, the resilient retractor 112 is formed in a smooth bend, as shown in FIG. 2 a , and gradually deflects away from the central axis 101 of the cannula 100 as the retractor is extended. Upon encountering the target vessel or tissue of interest, the vessel is restrained in the cradle 116 , and a lateral resilient force is exerted on the target vessel in a direction away from the cannula. The vessel is thus pushed away from the axis of the cannula 100 , isolating it from surrounding tissue or adjacent vessels such as tributaries or side branches. As a tributary is thus isolated, a surgical tool 120 such as cauterizing scissors may be safely employed to operate on the tributary without harming the sapphenous vein 118 . When retracted into the cannula 100 , the retractor 112 is again resiliently straightened or flattened.
In an alternate embodiment as illustrated in FIGS. 5 a and 5 b , a sliding tube 132 is added to provide operational versatility to cannula 100 . In a first position, the sliding tube 132 is retracted and the retractor 112 protrudes from the distal end at an angle with respect to the central axis 101 of the cannula 100 . In a second position, the sliding tube 132 is extended out, temporarily straightening the retractor 112 . As illustrated in FIG. 5 a , a sliding tube 132 , in a first position encases the retractor 112 up to the point at which the retractor 112 curves away from the central axis 101 of the cannula thus allowing the retractor 112 to displace and isolate a target vessel. The proximal end of the sliding tube 132 is linked to button 107 for translationally moving retractor 112 as well as actuating the sliding tube 132 . In one embodiment, as illustrated in FIG. 5 a , the sliding tube 132 is in a first position with the button 107 in an upright position. A spring 134 is coupled between a support structure 135 and the proximal end 137 of the sliding tube 132 . In the first position of sliding tube 132 , the spring 134 is extended fully and exerts little or no force on the sliding tube 132 . Of course, sliding tube 132 may be manually manipulated without linkage to a button 107 .
To extend the sliding tube 100 , button 107 is pushed down. As illustrated in FIG. 5 b , the button 107 has a cam surface 136 which pushes on the proximal end 137 of the sliding tube 132 as the button 107 is pressed. The sliding tube 132 is pushed forward, overcoming the resilient force of spring 134 , to encase the retractor 112 and decrease angle 117 between the distal end of the retractor 112 and the central axis 101 of the cannula 100 . Upon releasing the button 107 , the spring force urges the proximal end 137 of the sliding tube 132 back toward the first position against button 107 . The sliding tube 132 is formed of material having sufficient strength to force the retractor 112 to straighten out the angle 117 , and the retractor 112 is formed of resilient material having a sufficient flexibility to straighten out the angle 117 in response to a tube 132 being slid over the retractor 112 , but having sufficient rigidity to cradle and dissect a target vessel. Resiliency of the retractor 112 ensures return to the downwardly-curved shape after being released from tube 132 . Thus, in accordance with this embodiment, a user may employ the curved retractor for certain applications and employ the straightened form for other applications. A manual actuator may be configured in other ways than button 107 to extend the sliding tube 132 in response, for example, to being pulled up instead of pushed down.
Another embodiment employs a retractor 112 which has a naturally straight shape. As illustrated in FIGS. 6 a and 6 b , an angling device 140 is disposed between the distal end of the retractor 112 and the proximal end of the cannula. The angling device 140 may be positioned within the same lumens 113 as the retractor 112 and preferably may comprise two wires coupled to points below the cradle 116 of the retractor 112 substantially in parallel positions on each of the legs 141 , 142 .
Upon extending the retractor 112 using button 106 , the angling device 140 is extended with the retractor 112 . The angling device 140 is coupled to a handle 145 at the proximal end of the cannula 100 to facilitate establishing an angle in the retractor 112 by pulling with a backward force on the angling device 140 . As illustrated in FIG. 6 b , after the retractor 112 is extended, the angling device 140 is actuated and a bend is created in the retractor 112 as the backward force exerted on the distal end of the retractor is exerted against the relatively fixed position of the retractor legs 141 , 142 disposed within the lumens 113 . As shown in FIG. 6 c , the angling device 140 may also be located in a separate lumen 202 from the retractor 112 with part of the angling device 140 positioned outside of the cannula 100 when the retractor 112 is in the retracted position.
FIG. 7 a illustrates another embodiment of cannula 100 in which the retractor 112 is pre-formed with one leg 141 of the retractor 112 bent at an angle at its proximal end skewed to the axis of the distal end of the other leg 142 . The bent portion of the leg 141 may be linked to a sliding knob 147 for convenient manual manipulation of this embodiment of the invention. Upon sliding the knob 147 , the leg 142 coupled to knob 147 is twisted rotationally. The two legs 141 , 142 of retractor 112 are coupled together via cradle 116 . The axis of the second portion of the retractor 112 in the first position is at a first angle 117 to the axis of the cannula 100 , as shown in FIG. 7 b . As knob 147 is moved, leg 141 is rotated and crosses under leg 142 , as shown in FIG. 7 c . This causes cradle 116 to flip 180 degrees and bends the retractor 112 at a second angle 119 , as shown in FIG. 7 d . Thus, if a vessel is disposed on one side of cradle 116 or cannula 100 while the retractor 112 is in the first position, then upon rotating the knob 147 , the vessel is transported to the other side of the cannula 100 . This allows the user to isolate the vessel by simply actuating knob 147 .
FIG. 8 a illustrates a cut-away side view of button 106 on the handle 104 of cannula 100 , with an endoscope 126 positioned within cannula 100 . As mentioned above, button 106 is coupled to one leg 141 of the proximal end of retractor 112 . Sliding the button 106 in groove 146 translationally moves the retractor 112 . Groove 146 is preferably minimally wider than the shaft of button 106 to minimize excessive horizontal movement of button 106 while still allowing smooth translational movement of button 106 . As illustrated in FIG. 8 b , the button 106 may include locking or ratcheting teeth 152 to give tactile feedback of its location, and to positively retain the button and the associated leg 141 in an extended or retracted position. Several mating teeth 148 are located underneath groove 146 , and a spring member 150 is attached to button 106 to exert pressure against the base of groove 146 , to engage mating teeth 148 , 152 . When a force is applied on the top of button 106 , the interlocking sets of teeth are disengaged and button 106 can move freely. Upon achieving the desired extension or retraction of the leg 141 , button 106 is released and is retained place by the engaged teeth 148 , 152 .
FIG. 9 a illustrates a top view of cradle 116 in an embodiment in which the cradle 116 is formed by two legs 141 , 142 of retractor 112 . The distal end of the legs form “U”-shaped side guides. The top 144 of the distal portion of the “U” is preferably flattened. This provides atraumatic support for the target vessel retained within cradle 116 . Additionally, by minimizing the thickness of distal portion 144 , contact with other devices in close proximity with retractor 112 is minimized.
The cradle 116 may have other effective shapes, for example, as illustrated in FIG. 9 b in which a “C” ring element is attached to legs of the cradle 116 . The “C” ring may have a small hole 200 in one side with an axis approximately parallel to the axis of the retractor 112 . This hole 200 is used to hold suture or other ligating materials, and may also be used as a knot pusher. As shown in FIGS. 10 a and 10 b , in an alternate embodiment of the embodiment of FIG. 9 b , the retractor 112 is formed and flattened and a “C”-shaped ring is coupled to the retractor 112 by, for example, gluing or molding the “C” ring to the distal end of the retractor 112 , as shown in FIG. 10 c and 10 d.
Referring back to FIGS. 9 c , 9 d , and 9 e , the side guides of the cradle may include a loop 129 in a “V” shape, an arced “U” shape, or a semi-circular shape. In one embodiment, as illustrated in FIG. 9 f , the retractor 112 has only one leg 141 , and the cradle 116 is formed by the leg 141 . A stopper 160 is coupled to the end of the leg 141 to serve as a guide to retain the target vessel, and add a blunt surface to the end of the wire, for example, for pushing and probing tissue. FIG. 9 g illustrates a retractor 112 having a spur 204 formed in one or both legs 141 , 142 for allowing the retractor 112 to be used for dissection. Sinusoidal, half-sinusoidal, and other geometric configurations may be used equally effectively as the shape of loop 129 in accordance with the present invention.
FIG. 11 a illustrates a tip 1100 for use with a multi-lumen cannula 100 housing an endoscope 126 . The tapered tip 1100 may be removed from, and reattached to the distal end of a cannula 100 , as desired. Upon attachment, the tip 1100 seals the distal end of a cannula 100 in a fluid-tight manner. The tip 1100 is configured to provide dissection of the tissue surrounding the vessel of interest, and has a distal radius of approximately 0.045″ to reduce the hazard of penetrating the vessel of interest. The inner surface of the tip 1100 tapers to a sharp interior point and a slightly rounded exterior point and the tip 1100 has a uniform wall thickness. The tip 1100 preferably has taper angles of approximately 15° which provides a maximal, undistorted, visual field through an endoscope 126 . The tip 1100 tapers outward to a maximal diameter of about 12¾ mm at its shoulder to cover the cannula 100 body which also has a diameter of about 12¾ mm. All of these features allow the tip 1100 to effectively dissect tissue. The tip 1100 of FIG. 11 a has a central axis 1150 aligned with the central axis 1108 of the cannula 100 . The visual field provided by the endoscope 126 , although satisfactory for surgical procedures, is not complete because the endoscope 126 is in a lumen that is offset from the central axis 1108 of the cannula 100 . The endoscope 126 is offset because of the space required inside the cannula 100 for housing retractors and other instruments in adjacent lumens. FIG. 11 b illustrates this tip 1100 detached from the cannula 100 .
FIG. 12 a illustrates an offset tip 1200 for a cannula 100 in accordance with the present invention. The offset tip 1200 is a transparent, tapered tip as described above for use in endoscopic dissection of a vessel. However, in this embodiment the axis 1250 of the tip 1200 is skewed relative to the central axis 1108 of the cannula 100 . The axis 1250 of the tip 1200 is skewed approximately 8°, an angle that is chosen to align the apex 1232 of the tip 1200 with a central axis 1112 of the endoscope 126 , as shown in more detail in FIG. 12 b.
FIG. 12 b illustrates the offset tip 1200 housed in cannula 100 in more detail. The cannula 100 houses a 5 mm endoscope 126 having a central axis 1112 eccentric to the central axis 1108 of the cannula 100 . In order to bring the distal end or apex 1232 of the axis of the tapered tip 1200 into the center of the visual field along the central axis 1112 of the endoscope 126 , the tapered tip 1200 is tilted or inclined by approximately 8° toward the lumen housing the endoscope 126 . This allows the apex 1232 of the tip 1200 to approximately intersect with the central axis 1112 of the endoscope 126 . As illustrated in FIG. 12 b , the tip 1200 is inclined toward the central axis 1112 of the endo scope 126 without altering the taper angles 1236 and 1240 of the side walls. This is accomplished by forming a transition 1228 between the proximal or cylindrical portion 1204 of the tip 1200 and the distal or conical portion of the cannula body 1208 of the tip 1200 substantially along a plane 1230 that is skewed from normal to the central axis 1108 of the cannula 100 . The distal portion 1208 of the tip 1200 retains its conical shape and equal taper angles 1228 , 1236 between the side walls and the transition plane. The slight extension of the cannula body at the transition plane provides sufficient incline to allow the apex 1232 of the tip 1200 to intersect the central axis 1112 of the endoscope 126 . The tip 1200 may be formed of separate conical and cylindrical parts that are attached together, or the tip 1200 may be formed as an integrated structure in the shape thus described.
Alternatively, as shown in FIG. 12 c , the tip 1200 is inclined at a lesser angle, for example, 5 degrees, toward the axis 1112 of the endoscope 126 , positioning the axis 1250 of the distal end 1232 of the tip 1200 intermediate between the central axis 1108 of the cannula 100 and the axis 1112 of the endoscope 126 . Positioning the axis 1250 of the tip 1200 to this intermediate point allows the retention of steep conical angles in the tip 1200 which allow for easier advancement of the cannula 100 while using a minimal amount of force. The intermediate positioning also provides a more complete visual field as seen through endoscope 126 .
An alternate embodiment of an offset tip 1200 is shown in FIG. 13 in which the taper angles 1320 , 1324 of the side walls are selected to form the apex 1328 of the tip 1200 aligned with the central axis 1112 of the endoscope 126 . As illustrated, the lower region 1316 of the cylindrical part 1304 extends beyond the upper region 1312 of the cylindrical part at a plane of transition between cylindrical and tapered regions of the tip. However, in this embodiment, the taper angles 1320 , 1324 are not equal and the thirty degree angled conical configuration of the tapered part 1308 is not maintained. Rather, the lower taper angle 1324 is increased to an obtuse angle and the upper taper angle 1320 is a reduced acute angle relative to the plane of transition between the cylindrical and tapered portions of the tip. In this configuration of the conical portion 1308 , the apex 1328 of the tip 1200 aligns with the central axis 1112 of the endoscope 126 . Thus, in accordance with either embodiment, a tip 1200 is provided which allows a maximal visual field to be viewed by the surgeon via the endoscope 126 that is eccentric the central axis 1108 of the cannula 100 , but that is aligned with or near to the apex 1232 of the tip 1200 .
FIG. 14 a illustrates a perspective side view of the offset tip 1200 and mounting rod 1404 . The tip 1200 is attached to the cannula 100 via the long rod 1404 which extends through an eccentric lumen of the cannula 100 , as shown in FIG. 14 b , and the apex of the tip 1200 is tilted away from the rod 1404 and towards the endoscopic lumen (not shown). The elongated rod 1404 may be attached to the tip 1200 , or may be constructed as an integral part of the tip 1200 . The elongated rod 1404 preferably is secured in housing 1424 , shown in FIG. 14 c , via threads 1408 on the proximal end of rod 1404 and mating threads within nut or knob 1416 . The rod 1404 and housing 1424 abut against the proximal end of the cannula handle 1412 , as illustrated in the perspective side view of the assembled device shown in FIG. 14 d . Referring back to FIGS. 14 a - c , the housing 1424 includes a slot 1420 configured to slip over the light cable outlet 1428 on the endoscope 126 as assembled within the cannula 100 . The housing 1424 preferably contains a rotating nut 1416 which accepts the threaded proximal end 1408 of the rod 1404 . When tightened onto the rod 1404 , as shown in FIG. 14 d , the housing 1424 prevents the cannula 100 from rotating about the endoscope 126 by holding the endoscope 126 fixed with respect to the handle 1412 . This allows the operator to maintain the correct orientation of the endoscope 126 on the vessel. If the endoscope 126 is allowed to rotate freely, the image may turn sideways or upside down without the operator realizing it, and injury may occur to the vessel if the cannula 100 is advanced in the wrong direction.
In one embodiment, as shown in FIGS. 14 e and 14 f , the elongated rod 1404 slips into the housing 1424 via a groove 1450 near its proximal end, and passes through the main hole 1454 in the housing 1424 . The groove 1450 allows for the housing 1424 to cover the proximal end of the mounting rod 1404 without completely clearing the most proximal tip of the mounting rod 1404 . This allows more room for attaching the housing 1424 which lies between the elongated rod 1404 and additional optical components. The rod 1404 may contain an elastic section, or the rod 1404 may be somewhat elastic along its entire length to facilitate stretching the rod 1404 and pulling it into position in the slot 1454 on the housing 1424 , while locking the tip 1200 in place. The elastic force also facilitates sealing the tip 1200 against the distal face of the cannula body.
FIGS. 15 a and 15 b illustrates an alternate embodiment of offset tip 1200 and cannula 100 . In this embodiment, offset tip 1200 is formed with an elongated case 1500 which slides over the cannula body 100 and locks to the proximal end of cannula 100 . In this embodiment, proximal end of cannula 100 is threaded and allows a threaded proximal section of elongated case 1500 to mate securely to the cannula 100 .
In a surgical procedure using the tissue-dissecting cannula of the present invention, the surgeon first incises 1600 the skin overlying a vessel of interest to expose the vessel as an initial step of the procedure illustrated in the flow chart of FIG. 16 . A scissor tool is inserted 1602 into the incision to create a path to the vessel by dissecting the overlying tissue. Next, the tip 1200 of the cannula 100 is inserted 1604 into the incision to bluntly dissect tissue to form an initial tunnel along the vessel from the incision. The incision is then sealed 1608 using a blunt tip trocar and a tunnel is insufflated 1612 . The cannula is advanced 1616 along the vessel to dissect tissue adjacent the vessel under endoscopic visualization through the transparent tip. The offset tip 1200 with the apex thereof in alignment with the endoscope 126 provides a full visual field for the surgeon as the cannula 100 is advanced. The conical end of the tip 1200 dissects the tissue as the cannula 100 is advanced along the vessel. The surgeon dissects both on the anterior and posterior sides of the vessel to create a full 360 degree tunnel around the vessel. Once a selected surgical site is reached, the cannula 100 is removed 1620 from the incision seal and the tip 1200 is removed 1624 from the cannula 100 . In one embodiment, as described above, the tip 1200 is removed by unscrewing the threaded portion 1408 of the rod 1404 from the rotating nut 1416 . The tip housing 1424 itself is also removed in this embodiment. Insufflation is maintained and the cannula 100 without tip 1200 is inserted 1628 into the seal into the tunnel adjacent the vessel. Transecting devices are then inserted 1630 into the cannula 100 . Without tip 1200 disposed over the distal end, the cannula 100 can now be used for transecting 1632 side branches and the ends of the vessel of interest using endoscopic instruments that are selectively installed and removed within instrument lumens in the cannula body 100 . After these procedures are completed, the vessel may be removed 1636 .
FIG. 17 a illustrates another embodiment of an offset tip dilator 1700 . In this embodiment of the present invention, the tip 1700 also includes wing-like protrusions for enlarging or dilating a peri-vascular cavity in the course of separating a vessel from adjacent connective tissue. For example, after tissue dissection with an offset tip 1200 to form a tunnel or working cavity adjacent a target vessel by dissecting along the anterior and posterior sides of the vessel, the cannula 100 is removed from the distal end of the body, the offset tip 1200 is detached, and a second tip 1700 is attached to the distal end of the cannula body 100 . In one embodiment, the second tip 1700 includes a transparent tapered tip with planar wing-like protrusions or extensions disposed proximal to the distal end 1720 of the tip 1700 . The wing-like protrusions 1702 , 1704 each include a swept back leading edge. As shown in FIG. 17 b , the tip 1200 is tilted away from the mounting rod 1404 to align with the central axis of an endoscopic lumen (not shown). The wing-like protrusions 1702 , 1704 may also include curved distal and proximal edges, for example, in a parabolic configuration as shown in FIG. 17 c , providing a smoother withdrawal of the cannula 100 from the insufflated tunnel. The tip 1700 attaches to the cannula body 100 in the same manner as previously described with reference to the offset tip 1200 , with an elongated rod 1404 extending through a lumen of the cannula 100 and locking at the proximal end of the handle 1412 . The cannula 100 may thus be advanced through tissue under full-field endoscopic visualization through the tapered tip 1720 with the wing-like protrusions 1702 , 1704 extending substantially diametrically to facilitate tunnel dilation.
The wing-like protrusions 1702 , 1704 of the tip 1700 are arranged in substantially planar geometry in contrast to the solid bulbous, oval element described above. The planar configuration of the wing-like protrusions 1702 , 1704 substantially reduce the frontal profile of the dilator required to penetrate tissue, and thus reduces the resistive force encountered during advancement of the cannula 100 through tissue. Although the tissue-dilating force is exerted on tissue surrounding the cavity in a bilateral, substantially planar orientation by the outer edges of the wing-like protrusions 1702 , 1704 that dissect tissue forming the cavity walls, the dilated cavity may retain a round cross-section for example, within an insufflated cavity, in the same manner as if tissue dilation was performed using a solid oval dilator that applies dilating force circumferentially.
FIG. 18 illustrates a method of dilating tissue in accordance with one method embodiment of the present invention. The skin is incised 1800 overlying the vessel of interest, and the scissor tool is inserted into the incision to create a path to the vessel by dissecting the overlying tissue. The incision is then bluntly dissected 1804 using the offset tip 1200 to expose the vessel surface. The incision is sealed 1808 and a tunnel is insufflated 1812 . The cannula 100 is advanced 1816 along the vessel under endoscopic visualization through the transparent tip 1200 . After sufficient length of tunnel is formed adjacent the vessel, the cannula 100 is removed 1820 and the incision seal is removed or slid backwards to the proximal end of the cannula 100 . The offset tip 1200 is then replaced 1824 with the dilating tip 1700 . The seal is reinserted and the incision is sealed 1826 . The cannula 100 is advanced 1828 and the cavity is further dilated responsive to the advancement of the planar wing-like protrusions 1702 , 1704 through tissue forming the tunnel walls. The cannula 100 is removed 1832 a second time, and the incision seal is again removed or slid backwards to the proximal end of the cannula 100 . The dilating tip is removed 1836 and the incision is sealed 1837 . Transection devices are loaded 1838 through instrument lumens within the cannula body 100 into the cannula 100 and the cannula 100 is then inserted 1839 back into the incision. Without any tip covering the distal end of the cannula 100 , the vessel side branches and ends are transected 1840 using endoscopic instruments, and the vessel is then removed 1844 from the dilated tunnel. | A surgical apparatus includes an elongate cannula having a lumen extending therein between proximal and distal ends, a retractor disposed to slide within the lumen to extend a distal end thereof beyond the distal end of the cannula, an angling device connected to the retractor near the distal end of the retractor and extending within the cannula toward the proximal end thereof for selectively deflecting the distal end of the retractor away from a central axis of the cannula in response to manual manipulation of the angling device from near the proximal end of the cannula, wherein the distal end of the retractor is configured to move, upon extension, an object away from the central axis of the cannula. | 0 |
FIELD OF THE INVENTION
This invention relates generally to rotatable drying cylinder assemblies and more particularly to such drying cylinder assemblies which employ steam flowing to the interior thereof for heating thereof and, further, to apparatus associated with such drying cylinder assemblies for the removal of condensate, resulting from the cooling of said steam, from the interior of said drying cylinder assembly.
BACKGROUND OF THE INVENTION
In various industries or arts, it is necessary, as part of the overall process, to dry a continuous sheet or strip of material. For example, in the art of paper-making, the relatively wet or damp strip or web of paper fibers is often passed over and mostly about a rotatable drum or cylinder assembly which is heated in order to thereby evaporate the moisture of the wet or damp paper sheet in contact with and passing about the outer cylindrical surface of such rotatable drum or cylinder assembly.
The prior art has employed steam for the heating of such rotatable drying drums or cylinder assemblies. More specifically, heretofore, the prior art has employed a drying cylinder or drum assembly comprised of a cylindrical shell having axially closed end-walls defining an inner chamber into which, as through the axis of rotation in an end wall, steam is supplied in order to sufficiently heat the cylindrical shell, and the outer cylindrical surface thereof, and thereby achieve the desired degree of drying of the paper sheet or material passing in contact with the said outer cylindrical surface.
The steam thusly admitted into the inner chamber of the drying cylinder or drum assembly, upon giving-up some of its heat, forms a condensate within said inner chamber and, obviously, such condensate must be removed in order to maintain a continuous drying process.
Heretofore, the prior art as disclosed, for example, by Austria Letters Patent No. 244,318, has proposed the use of a suction type conduit means for the removal of condensate from the interior of such a steam heated rotatable drying cylinder assembly. In such a proposed prior art apparatus, the pressure generally downsteam of the condensate-removing conduit means is maintained at a magnitude less than the pressure within the interior of the drying cylinder assembly and the steam, to the interior of the cylinder assembly, is supplied in such a volume and under such a pressure as to result in a portion of such steam flowing as a high speed stream through a gap or clearance formed between the surface of the film of condensate and the juxtaposed rim of an inlet leading to and cooperating with the suction conduit means. The purpose of creating such a high speed stream was to cause the stream to entrain therein part of the liquid forming the film of condensate. Such a prior art proposed condensate removing system was based on the assumption that the condensate would, during comparatively high peripheral velocities of the drying cylinder assembly, form a continuous inner cylindrical ring or film of constant thickness on the inner surface of the cylindrical shell. Such a prior art proposed condensate-removing system was found to be generally acceptable even where the peripheral velocity of the drying cylinder assembly was so low as to result in a sump, puddle or pool of condensate in the lower portion of the interior of the drying cylinder assembly.
However, especially in the paper making art, the working speeds of such drying cylinder assemblies have undergone, in the recent past, steady increases as to thereby obtain greater rates of paper production. It has been found that in such instances, where significantly higher rotational velocities are experienced by the drying cylinder assemblies, a recognizable continuous strip-like pattern is formed in the paper sheet. Such strip pattern has been found to be, generally, over-dried as compared to the remainder of the stock forming the paper sheet. Further, it has been found that such strip pattern is produced in the paper sheet at a location which corresponds to the axial position, along the axis of the drying cylinder assembly, at which the inlet end or intake head of the condensate-removing conduit means is situated.
It has been found that at such relatively high rotational speeds, the remaining condensate (not removed by the intake head or inlet structure) forms a spurting and turbulent zone behind the intake head or inlet structure. As a consequence of such turbulent zone, in the condensate layer remaining behind the inlet structure, the rate of heat transfer, in that zone, from the interior to the exterior cylindrical surface of the drying cylinder assembly is significantly increased causing the outer cylindrical surface to have a ring-like annular area of a temperature which is too hot and such annular area then has the effect of comparatively over-drying the portion of the paper sheet coming in contact therewith.
Heretofore, it has been proposed by the prior art that in order to overcome such a problem of an over-heated zone on the drying cylinder one should employ an intake head or inlet structure sometimes referred to as a "peel-syphon" type and disclosed, for example, in Federal Republic of Germany Patent Office Publication No. AS-29-03-170. In such a prior art inlet structure the inlet opening thereof has a somewhat peeling action on the film or layer of condensate. The kinetic energy of such peeled portion of the condensate partly assists the flow of such peeled condensate into and through the associated condensate-removing conduit means. However, the major motivating and removing force of such peeled condensate is the transporting and entraining effect of a high speed stream of steam flowing through a gap or clearance formed between the surface of the film of condensate and the juxtaposed edge or rim of the inlet opening of the inlet structure (much as disclosed by said Austria Letters Patent No. 244,318). One of the serious disadvantages of such a prior art inlet structure is that there is a comparatively high usage of steam; further, the thickness of the remaining condensate film or layer is comparatively large resulting in the rate of heat transfer to the outer cylindrical surface of the dryer cylinder assembly being reduced from the desired rate. Still further, such a "peel-syphon" type of structure proposed by the prior art is capable of removing at most only a small portion of the condensate from the drying cylinder when such drying cylinder is used in a drying process employing slow working speeds resulting in the formation of a condensate sump or pool in the lower part of the interior of the drying cylinder.
Other prior art attempts at eliminating the creation of such an overly-heated zone on the drying cylinder have not been found to be acceptable. One suggestion was to form an inner circumferential groove within the inner surface of the drying cylinder with such groove being positioned generally in a plane passing normal to the axis of rotation of the drying cylinder and passing through the medial portion of the intake head or inlet structure. Such was found not to correct the problem of creating an over-heated zone.
The prior art also suggested making the drying cylinder axially overly-long as to be significantly axially longer than the width of the paper sheet to be passed thereagainst and then placing the condensate intake head or inlet structure at a position as to be situated axially beyond the edge of the paper sheet. This has not been found acceptable.
The prior art has also suggested that a plurality of drying cylinder assemblies, arranged in series, be employed for collectively drying the paper sheet sequentially engaging such drying cylinders. More specifically, the prior art contemplated positioning the respective condensate intake heads or inlet structures at differing axial locations as to, in effect, created respective overly-heated zones which would not be aligned with each other and then partially but unevenly drying the paper sheet as it passes against each drying cylinder with the hope that thereby, through such overlapping cumulative drying the finally dried paper sheet would not exhibit the undesired overly-dried strip therein.
The prior art has also proposed preventing the creation of an overly-heated zone, on the dryer cylinder, by employing a heat insulating ring on the inner cylindrical surface of the drying cylinder as to be passing (during rotation of the dryer cylinder) in juxtaposition to the condensate intake head or inlet structure. Such a prior art structure, as disclosed generally by Federal Republic of Germany Patent Office Publication No. OS-29-30-985, has not been found acceptable.
Further, the prior art has proposed the use of rotating, instead of stationary, condensate intake heads or inlet structures in order to prevent the creation of an overly heated zone on the drying cylinder. However, this has not been found acceptable especially in view of the dramatically increased pressure differential and steam consumption necessary to overcome the centrifugal force tending to prevent the condensate from flowing through the associated conduit means toward the axis of rotation.
The invention as herein disclosed and described is primarily directed to the solution of the aforestated as well as other related and attendant problems of the prior art.
SUMMARY OF THE INVENTION
According to the invention, an intake structure, for receiving therein condensate from an inner chamber of a steam heated drying cylinder assembly which is rotatable about an axis of rotation, which has a generally cylindrical inner surface defining a portion of said inner chamber and against which said condensate forms, and which has a stationary condensate-transporting conduit means for delivering condensate to a receiving area externally of said drying cylinder assembly, comprises nozzle-like body means, an inlet opening formed in said nozzle-like body means, an outlet formed in said nozzle-like body means and being effective for communication with said stationary condensate-transporting conduit means, said inlet opening being juxtaposed to and open towards said cylindrical inner surface when said nozzle-like body means is operatively connected to said stationary condensate-transporting conduit means in order to achieve said communication with said outlet, said inlet opening having forwardly and rearwardly disposed wall portions, said nozzle-like body means when operatively connected to said stationary condensate-transporting conduit means being so positioned as to have said forwardly and rearwardly disposed wall portions so arranged with respect to each other as to result in the rotating cylindrical inner surface first traverse said forwardly disposed wall portion and subsequently traverse said rearwardly disposed wall portion, and wherein said rearwardly disposed wall portion has a generally inner surface means effective for scooping at least a portion of said condensate from said rotating cylindrical inner surface and directing such scooped condensate into said stationary condensate-transporting conduit means.
Various other general and specific objects, advantages and aspects of the invention will become apparent when reference is made to the following detailed description considered in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings, wherein for purposes of clarity certain details and/or elements may be omitted from one or more views:
FIG. 1, in somewhat simplified and/or schematic form, illustrates in axial cross-section a fragmentary portion of a drying cylinder or drum assembly employing apparatus, embodying teachings of the invention, for removing condensate from the interior of the drying cylinder assembly;
FIG. 2 is a relatively enlarged cross-sectional view taken generally on the plane of line II--II of FIG. 1 and looking in the direction of the arrows and illustrating a preferred embodiment of an inlet structure according to the invention;
FIG. 3 is a view taken generally in the direction of arrow III of FIG. 2;
FIG. 4 is a bottom elevational view of another embodiment of an inlet or intake structure embodying teachings of the invention;
FIG. 5 is a cross-sectional view taken generally on the plane of line V--V of FIG. 4 and looking in the direction of the arrows;
FIG. 6 is a bottom elevational view of still another embodiment of an inlet or intake structure embodying teachings of the invention; and
FIG. 7 is a cross-sectional view taken generally on the plane of line VII--VII of FIG. 6 and looking in the direction of the arrows.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now in greater detail to the drawings, a rotatable drying cylinder or drum assembly 10, shown fragmentarily, comprises a cylindrical portion 42 with end closure walls, one of which is illustrated at 11, defining therewithin a chamber 44. The outer cylindrical surface 46 may be considered the rotatable drying surface against which, for example, the paper sheet is brought into contact for the drying thereof. The inner cylindrical surface 48 is that surface against which the steam condensate collects during operation and rotation of the cylinder assembly 10.
In the arrangement illustrated a portion 14, of the overall machine structure or apparatus, serves as a mounting or support as for an associated stationary bearing housing means 13 which, in turn, houses, for example, roller bearing means 12. A generally tubular extension portion 11', which may be carried by the end wall 11, serves as a journal means by being received as within bearing means 12 for rotation about the axis 50. A support portion similar to portion 14 and, for example, a solid journal means functionally similar to 11' may be provided as at the opposite axial end of the cylinder assembly 10.
A suitable source of steam 52 is operatively connected, as through conduit means 54 and coupling means 15, to inner chamber 44 by means of a stationary steam feed-pipe or conduit 17 which, as depicted, is carried and supported by the coupling means 15. Suitable ring-like sealing means 16 is preferably provided as between the stationary coupling means 15 and the rotatable hollow or tubular journal portion 11'.
A condensate-removing or transporting conduit means 56 is illustrated as comprising conduit portions 18 and 19. Conduit portion 18 extends axially through the inner passage 58 of stationary steam feed-conduit 17 and has oppositely situated end portions 60 and 62 with end portion 60 being operatively connected to generally radially extending conduit portion 19 and with end portion 62 being adapted for returning the removed condensate to a related condensate receiving means 64.
The radially outer-most portion of conduit section 19 may be provided as with a tubular connector portion 66, secured to and carried by conduit 19 and also secured to one end of a support arm 20 which has its other end fixedly secured as to the projecting end of stationary steam feed-conduit 17. The connector 66, serving as a functional extension of conduit portion 19, slidably telescopingly receives a conduit portion 21 of the associated intake or inlet structure 22 thereby providing for some degree of movement, radially of axis 50, of inlet structure 22. A spring 22' serves to hold the inlet structure 22 spaced a small distance away from inner cylindrical surface 48 and allows for limited movement or deflection of the inlet structure 22 relative to the axis 50.
Referring to FIGS. 2 and 3, the preferred embodiment of the inlet or intake structure 22 is illustrated as comprising a nozzle-like generally box-shaped body means 68 which, although being capable of being made of any suitable material, in the preferred embodiment, is formed of plastic material. The use of plastic material minimizes the magnitude of the frictional forces generated should the body means 68 touch inner cylindrical surface 48 during rotation of cylinder assembly 10. A flange member 21a is secured to conduit portion 21, as by welding, and body means 68 is, in turn, suitably secured to flange 21a as by any suitable means as for example by screws (not shown).
As depicted, in the preferred embodiment, nozzle-like body means 68 comprises a forwardly disposed wall portion 23 and a rearwardly disposed wall portion 26 which are, preferably, integrally formed with lateral or longitudinally extending opposed side wall portions 24 and 25.
The inlet opening 70 of the nozzle-like body means 68 is formed in the radially outer-most portion of the body means 68, as to be juxtaposed to inner cylindrical surface 48, and is peripherally defined as by relatively sharp edge 72 and edges 74, 76, 78 and 80.
In the preferred embodiment, the inner surface 82 of rearward wall 26 is formed as provide a relatively sharp edge 72, at its lower-most portion as viewed in FIG. 2, so that such edge 72, serving as for example a peeling-knife or scoop, effectively peels or scoops a layer of condensate from the rotating cylinder assembly 10 (rotation being in the direction of arrow 84 of FIG. 2) and directs such scooped condensate into conduit portion 21 and communicating condensate-removing conduit means 56 for transport to the receiving means 64. Further, in the preferred form, surface 82 is contoured as to provide a smooth and continuous transitional surface so that, as much as possible, the kinetic energy of the condensate being scooped will be used in causing the condensate to flow into through conduit means 21 and 56.
The outer surface of rearward wall 26 is preferably formed as to be inclined in the order of 30°. More particularly, the angle formed by the outer surface of wall 26 would be measured with respect to a reference plane tangent to an arc passing through point 88, as at the lower edge of the inclined surface, and having its center of rotation coincident with axis 50. Further, in the preferred embodiment, surface 82, in the region relatively close to peeling or scooping edge 72, would form a similarly inclined angle in the order of 30°.
In the preferred embodiment, the overall exterior width of nozzle-like body means 68 (as best seen in FIG. 3) is only in the order of one-quarter the overall exterior length of such body means 68 and the inner width, b, of the opening 70 is preferably only equal to the diameter, d, of conduit means 21.
Even though not considered to be essential, in the preferred embodiment forward wall portion 23 has a recess or clearance passage 27 formed therethrough as to provide for some degree of communication as between the interior of opening 70 and an area forward (to the left as viewed in FIG. 2) of forward wall portion 23. Such opening or clearance 27 enables a portion of the steam (supplied to chamber 44 via steam feed-conduit means 17) to stream therethrough and into the interior of nozzle body means 68 and, in so doing, also entrain some of the condensate to be carried away via conduit means 56.
In the embodiment of FIGS. 4 and 5, the nozzle-like body means 32 is illustrated as comprising an opening or passage means 90 which, when viewed as in FIG. 4, is of a venturi-like configuration. More particularly, the forward end 92 of body means 32 has formed therein the inlet end 94 of passage or opening 90 while the rearward wall 26' (functionally similar or equivalent to wall 26 of FIG. 2) is provided with a peeling or scooping edge 72' (functionally similar or equivalent to edge 72 of FIG. 2). A surface 96 forms the upper surface (as viewed in FIG. 5) of the passage or opening 90 while the generally longitudinal side surfaces of the opening 90 are formed as by opposed inner surfaces 98 and 100 respectively formed as on integrally formed side wall portions 102 and 104, while the rearward surface of opening 90 is defined by inclined inner surface 82' which is functionally similar and equivalent to surface 82 of FIG. 2. As best seen in FIG. 4, side surfaces 98 and 100 may each be considered as comprising, generally three surface portions or zones. That is, surface means 98 may be considered as comprising forwardly situated surface portion 106, rearwardly situated surface portion 108 and intermediate joining surface portion 110, while surface means 100 may be considered as comprising forwardly situated surface portion 112, rearwardly situated surface portion 114 and intermediate joining surface portion 116. Surfaces 106 and 112 cooperate to define a relatively wide entrance-like area and progressively narrow such area to where a minimal width is cooperatively defined by opposed generally rounded surface portions 110 and 116 which effectively define the venturi throat 29. Rearwardly or downstream of such venturi throat 29, the opposed surfaces 108 and 114 progressively widen the space therebetween until the width thereof is equal to the diameter of the exit conduit portion 118 which, preferably is equal to the flow diameter of the conduit portion 21 (shown in FIGS. 1 and 2) which may be operatively connected to body means 32 in the same manner as described with regard to body means 68 of FIG. 2.
Further, the body means 32 when assembled into an overall inlet structure, as, for example disclosed in FIGS. 2 and 3, the position of such body means 32 would be as that illustrated by body means 68 and thereby placing the stream entrance 94 to be first traversed by the rotating cylinder 42. The entrance 94, as should now be apparent, of relatively little height (as viewed in FIG. 5) but is of very considerable width (as viewed in 4). As the condensate 9 is effectively impacted into passage or opening 90 and as it flows, relatively, through throat 29 the velocity of such condensate is increased thereby aiding in the entrainment of additional condensate rearwardly of throat 29 and increasing the kinetic energy of the condensate to enhance its subsequent flow against transitional surface means 82' and out of exit conduit portion 118.
As in the embodiment of FIGS. 2 and 3, in the preferred configuration of the embodiment of FIGS. 4 and 5, the rearward wall 26' has its outer surface 120 also inclined at an angle in the order of 30° with such being determined generally in the same manner as described with regard to the outer inclined surface of wall 26 of FIG. 2. Further, it is preferred that at least a portion of the transitional surface 82', closely situated to the relatively sharp peeling or scooping edge 72', also be at the same angle (i.e. in the order of 30°) as also discussed in regard to FIG. 2. The outer surfaces 33--33 of side wall portions 102 and 104 are of arcuate configuration as to be generally concentric to the inner cylindrical surface 48, of cylindrical assembly 10, but closely spaced therefrom. If desired, a passage 31 may be formed through rearward wall 26' as to, for example, have a location and configuration as generally depicted in phantom line at 31 of each of FIGS. 4 and 5. The provision of such an aperture or passage 31 is discussed in said Federal Republic of Germany Patent Office Publication No. AS-29-03-170.
FIGS. 6 and 7 illustrate yet another embodiment of the invention. In FIGS. 6 and 7, except as otherwise noted, elements which are like or similar to those of FIGS. 6 and 7 (or FIGS. 2 and 3) are identified with like reference numbers.
In the main, nozzle-like body means 36 departs from body means 32 (of FIGS. 4 and 5) by having, for example, surface 96 more nearly raised and then having a relatively short downwardly sloping surface portion 122 leading to the entrance 94. Further, the side walls are contoured as to have respective surface portions 40--40 blending generally inwardly and toward the exit conduit portion 118. Such blending of surfaces may start, for example, and preferably, in the region of and preferably slightly forwardly of the venturi throat 29. As a consequence relatively narrow outwardly projecting wall surfaces 39--39 are formed which, in turn, have inner surface portions 124 and 126, preferably spaced from each other a distance equal to the diameter of the exit conduit portion 118, which tend to confine condensate therebetween and channel the flow thereof directly to such exit conduit portion 118 and conduit means 21 communicating therewith.
As stated with regard to the body means 32 of FIGS. 4 and 5, the body means 36 of FIGS. 6 and 7 may be operatively connected to conduit means or section 21 in the same manner as discussed with reference to FIGS. 2 and 3.
As already disclosed, it is preferred that the width, b, (FIG. 2) of the opening or inlet of the body means be at least equal to the inner diameter, d, of the rising conduit 21. Further, in the event that the flow passage of such a rising pipe section 21 is of a cross-sectional configuration other than circular, it is preferred that such inner width, b, be at most equal to: ##EQU1## where A is equal to the cross-sectional area of the flow passage of such a rising pipe section 21 and π is the mathematical constant, pi.
It has been found that by providing a rearward wall, as at 26 and/or 26', and forming the rearward outer surface thereof, as at, for example, 120, at an angle in the order of 30°, the condensate turbulance experienced with the prior art structures directly behind the inlet or intake structure is at least greatly reduced. Consequently, the over-heated ring-like or annular area on the outer surface of the drying cylinder, resulting from such condensate turbulence in the prior art is effectively eliminated thereby preventing the occurrence of the over-dried strip pattern in the paper sheet being dried.
As typically illustrated, for example, by FIG. 7, the rearwardly situated wall 26' is preferably formed as to have a thickness which will maintain the structural integrity thereof and yet present surface 120 as close as possible to the inner surface 82' thereby effectively resulting in the distance as from edge 72' to point or edge 88 being at a minimum.
As already disclosed, a possible embodiment of the invention comprises side intake-passage defining or limiting walls (for example, 25 and 25 of FIG. 3 or 102 104 of FIG. 4) which extend effectively for the full length of the lower-most portion of the body means (68 or 32) in close proximity to the curvature of the inner cylindrical surface 48 of cylinder 42.
Also, as already disclosed, a possible embodiment of the invention comprises side intake-passage defining or limiting walls (for example 40--40 of FIG. 6) which are effectively cut-back or contoured as to extend further away from the inner cylindrical surface 48 of cylinder 42 as such surfaces (40--40) more nearly approach the rearward portion of the intake or inlet cavity or chamber. This, of course, tends to direct greater flows of condensate smoothly into the conduit means 21.
Still further, a possible embodiment of the invention comprises an aperture or passage means, as generally indicated at 31 of FIGS. 4 and 5, formed through the rearward wall 26' as to thereby permit the escape of a portion of the steam, streaming into the inlet or intake structure, so as not to in effect cause a choking effect as in the conduit means 21 by an excess of steam which, in turn, would diminish the flow of condensate therethrough.
It is contemplated that the invention may be employed in an overall system wherein a pressure differential is created, as by exposing conduit means 56 to a vacuum source, in order to thereby assist in the flow of condensate from chamber 44 to receiving means 64. However, it has been discovered that inlet or intake structures embodying teachings of the invention function so well that it is not necessary to create such pressure differentials. This, of course, results in a savings in the cost of producing such a pressure differential and, further, prevents the occurrence of any damage to the associated product, as for example paper sheet, if in a system employing the invention and employing a created pressure differential a condition should occur whereby a loss of such pressure differential is experienced.
Although only a preferred embodiment and selected modifications of the invention have been disclosed and described, it is apparent that other embodiments and modifications of the invention are possible within the scope of the appended claims. | A relatively stationary pipe or conduit, for the removal of a condensate or liquid from the interior of a steam heated rotatable drying drum or cylinder assembly and adapted for connection to a source of relatively low or sub-atmospheric pressure, has an inner end portion, disposed within the drum or cylinder assembly, which is provided with an inlet opening or port disposed in juxtaposition and close proximity to an inner cylindrical surface of the cylinder assembly; the inlet opening has a generally rearwardly situated wall which is substantially inclined as with respect to a radial plane of the cylinder assembly as to provide for enhanced transitional flow of the condensate from the inner cylindrical surface of the cylinder assembly to the condensate-removing pipe or conduit. | 3 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to Workflow-Management-Systems. More particularly the present invention relates to a method and system for writing audit trails in Workflow-Management-Systems.
[0003] 2. Description and Disadvantages of Prior Art
[0004] A new area of technology with increasing importance is the domain of Workflow-Management-Systems (WFMS). WFMS support the modeling and execution of business processes. Business processes executed within a WFMS environment control which piece of work of a network of pieces of work will be performed by whom and which resources are exploited for this work. The individual pieces of work might be distributed across a multitude of different computer systems connected by some type of network. A thorough representation of WFMS technology is given by Frank Leymann and Dieter Roller, Production Workflow: Concepts and Techniques, Prentice-Hall, Upper Saddle River, N.J., 2000.
[0005] The product “IBM MQSeries Workflow” represents such a typical modern, sophisticated, and powerful workflow management system. It supports the modeling of business processes as a network of activities. This network of activities, the process model, is constructed as a directed, acyclic, weighted, colored graph. The nodes of the graph represent the activities which are performed. The edges of the graph, the control connectors, describe the potential sequence of execution of the activities. Definition of the process graph is via the IBM MQSeries Flow Definition Language (FDL) or the built-in graphical editor.
[0006] A particular instance of said process graph is called a process model, which is a template from which process instances are created. The actual execution of a particular process instance depends on data (fields) associated with the process instance, the context. The schema of the context, such as the names and types of the appropriate fields is described on the process model level; the actual data of the context (called shortly context), that means the values assumed by the different fields, is either already defined at the process model level as constants (default values) is created when a particular process instance is being carried out. Thus the context causes for different process instances to have different execution histories.
[0007] The runtime component of the WFMS, called the navigator or execution server, creates process instances from these process models, interprets these process instances, and distributes the execution of appropriate activities to the right person at the right place, for example by assigning tasks to a work list maintained for the respective person.
[0008] WFMSs in general support the writing of an audit trail, a collection of audit trail records, to an audit trail store. An audit trail record contains all relevant information about a particular event in the life or a process or activity, such as the start of a process or the completion of an activity. Thus the audit trail contains the more or less the fine-grained execution history of a particular process instance.
[0009] The audit trail can be used for many purposes: for example, it may be required for legal reasons to keep the complete execution history of each executed business, or it can be used to perform an analysis of the business processes to determine bottlenecks or possible improvements.
[0010] The properties of the audit trail, such as the location of storage and underlying persistence mechanism, can normally be specified by the user. The persistence, for example, could be provided by as a relational database managed by a relational database management system, a queue managed by a message qeueing system, or a message sent to an e-mail system. Not all WFMSs support the specification of the properties of the audit trail; MQSeries Workflow, for example, only supports a particular table in a relational database as the location and persistence mechanism for the audit trail.
[0011] The amount of audit trail records that are written is either fixed or can be specified by the process modeler on the model level, that means on the level of the process model or on the level of the activity within the process model. In MQSeries Workflow this is specified via the AUDIT keyword. Parameters for the AUDIT keyword are NO, CONDENSED, and FULL. NO indicates that no audit trail is written at all, CONDENSED that only important events are written to the audit trail, and FULL that all events are written to the audit trail.
[0012] Typically, WFMSs support inheritance for audit trail specifications. If no specification is available for a dependent object, this object inherits the specification from it's parent. If no audit specification is provided for an activity, for example, the audit specifications associated with the encompassing process model are used; if no audit specification is provided for a process model, the global audit specifications of the workflow management system are used.
[0013] A most important problem associated with this state of the art technology is a significant performance degradation of the WFMS when carrying out process instances of a process model in parallel and writing audit trail records to a common (shared) audit trail. This generates contention situations for said audit trail. Process instances, which actually would be ready to proceed independently from one another, have to wait for getting access to the audit trail store. The overall performance of WFMS suffers degradation.
[0014] Another most important problem with the state of the art technology is that the audit trail grows rather quickly in size, which causes performance to suffer as the insertion of new audit trail records may become more expensive.
[0015] Another problem with the state of the art technology is that the fast growth of the audit trail makes maintenance not only cumbersome, but also more expensive as the removal of old audit trail records from the audit trail becomes more expensive.
OBJECTIVE OF THE INVENTION
[0016] The invention is based on the objective to improve or to optimize the performance of a WFMS, in particular to improve or to optimize the audit trail processing of a WFMS.
SUMMARY AND ADVANTAGES OF THE INVENTION
[0017] The objectives of the invention are solved by the independent claims. Further advantageous arrangements and embodiments of the invention are set forth in the respective subclaims.
[0018] The concept underlying the invention is to have multiple audit trails and dynamically select either the most appropriate audit trail or a user-specified audit trail. The objective is solved by evaluation of the appropriate definitions, either given for a particular process model or specified globally for the workflow management system level, particularly comprising the following steps:
[0019] Assigning a multitude of audits trails as potential targets for audit trail records to said WFMS, and
[0020] Assigning an audit trail distribution strategy to said WFMS, comprising a specification which of said potential targets to be used for writing an audit trail record, and
[0021] Dynamically analyzing for a current audit trail record said distribution strategy and determining a current target from said multitude of audit trails, and
[0022] Writing said current audit trail record to said current target.
[0023] The current invention contrasts to the prior art approaches, where WFMSs were only supporting a common (shared) audit trail for all process instances and activity instances. By supporting multiple audit trails and dynamically selecting the appropriate audit trail based on definitions on the workflow management system level or process model and activity within process model level, distinct audit trails are written.
[0024] The most important advantage of the current invention is that the contention on the audit trail is reduced as no longer are all audit trail records written to the same audit trail. This allows carrying out of process instances in parallel without the need of waiting for the audit trail to become available.
[0025] Another important aspect is that the writing and removal of audit trail records in audit trails is much more efficient.
[0026] By implementing the present invention, the response time of requests, the processing of process instances, and the throughput of the WFMS is improved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] [0027]FIG. 1 shows the structure of a workflow management system that supports parallel processing for carrying out process instances and supports multiple audit trails according to a first embodiment of the present invention,
[0028] [0028]FIG. 2 shows an example of the definition of an audit trail that is handled as a table managed by a relational database management system according to a second embodiment of the present invention,
[0029] [0029]FIG. 3 shows an example of the definition of the default audit trail to be used by the workflow management if not another audit trail specification is provided, according to a third embodiment of the present invention,
[0030] [0030]FIG. 4 shows an example of a server controlled selection of the appropriate audit trail according to a fourth embodiment of the present invention,
[0031] [0031]FIG. 5 shows an example of a process model controlled selection of the appropriate audit trail according to a fifth embodiment of the present invention,
[0032] [0032]FIG. 6 shows an example of a process model, context based, controlled selection of the audit trail according to a sixth embodiment of the present invention,
[0033] [0033]FIG. 7 shows an example of an activity controlled selection of the audit trail according to a seventh embodiment of the present invention,
[0034] [0034]FIG. 8 shows an example of an activity, context based, controlled selection of the audit trail according to an eight embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0035] The current invention is illustrated based on IBM's MQSeries Workflow workflow management system. Of course any other WFMS could be used instead. Furthermore the current teaching applies also to any other type of system which offers WFMS functionalities not as a separate WFMS but within some other type of system.
[0036] Introduction
[0037] The following is a short outline on the basic concepts of a workflow management system based on IBM's MQSeries Workflow WFMS as far as it is of importance for the current invention.
[0038] From an enterprise point of view the management of business processes is becoming increasingly important. Business processes or process for short control which piece of work will be performed by whom and which resources are exploited for this work, i.e. a business process describes how an enterprise will achieve its business goals. A WFMS may support both, the modeling of business processes and their execution. Modeling of a business process as a syntactical unit in a way that is directly supported by a software system is extremely desirable. Moreover, the software system can also work as an interpreter basically getting as input such a model. The model, called a process model or workflow model, can then be instantiated and the individual sequence of work steps depending on the context of the instantiation of the model can be determined. Such a model of a business process can be perceived as a template for a class of similar processes performed within an enterprise; it is a schema describing all possible execution variants of a particular kind of business process. An instance of such a model and its interpretation represents an individual process, i.e. a concrete, context dependent execution of a variant prescribed by the model. A WFMS facilitates the management of business processes. It provides a means to describe models of business processes (build time) and it drives business processes based on an associated model (run time). The meta model of IBM's WFMS MQSeries Workflow, i.e. the syntactical elements provided for describing business process models, and the meaning and interpretation of these syntactical elements, is described next.
[0039] A process model is a complete representation of a process, comprising a process diagram and the settings that define the logic behind the components of the diagram. Important components of a MQSeries Workflow process model are:
[0040] Processes
[0041] Activities
[0042] Blocks
[0043] Control Flows
[0044] Connectors
[0045] Data Containers
[0046] Data Structures
[0047] Programs
[0048] Staff
[0049] Not all of these elements will be described below.
[0050] Activities are the fundamental elements of the meta model. An activity represents a business action that is from a certain perspective a semantic entity of its own.
[0051] A MQSeries Workflow process model consists of the following types of activities:
[0052] Program activity: Has a program assigned to perform it. The program is invoked when the activity is started. In a fully automated workflow, the program performs the activity without human intervention. Otherwise, the user must start the activity by selecting it from a runtime work list.
[0053] Process activity: Has a (sub-) process assigned to perform it. The process is invoked when the activity is started. A process activity represents a way to reuse a set of activities that are common to different processes.
[0054] The flow of control, i.e. the control flow through a running process determines the sequence in which activities are executed. The MQSeries Workflow workflow manager navigates a path through the process.
[0055] The results that are in general produced by the work represented by an activity is put into an output container, which is associated with each activity. Since an activity will in general require to access output containers of other activities, each activity is associated in addition with an input container too.
[0056] Connectors link activities in a process model. Using connectors, one defines the sequence of activities and the transmission of data between activities. Since activities might not be executed arbitrarily they are bound together via control connectors. A control connector might be perceived as a directed edge between two activities; the activity at the connector's end point cannot start before the activity at the start point of the connector has finished (successfully). Control connectors model thus the potential flow of control within a business process model. Data connectors specify the flow of data in a workflow model. A data connector originates from an activity or a block, and has an activity or a block as its target. One can specify that output data is to go to one target or to multiple targets. A target can have more than one incoming data connector.
[0057] A process definition includes modeling of activities, control connectors between the activities, input/output containers, and data connectors. A process is represented as a directed acyclic graph with the activities as nodes and the control/data connectors as the edges of the graph. The graph is manipulated via a built-in graphic editor. The data containers are specified as named data structures. These data structures themselves are specified via the DataStructureDefinition facility. Program activities are implemented through programs. The programs are registered via the Program Definition facility. Blocks contain the same constructs as processes, such as activities, control connectors etc. Process activities are implemented as processes. These subprocesses are defined separately as regular, named processes with all its usual properties. Process activities offer great flexibility for process definition. It not only allows the construction of a process through permanent refinement of activities into program and process activities (top-down), but also the building of a process out of a set of existing processes (bottom-up).
[0058] All programs which implement program activities are defined via the Program Registration Facility. Registered for each program is the name of the program, its location, and the invocation string. The invocation string consists of the program name and the command string passed to the program.
[0059] Multiple Audit Trails
[0060] In the prior art, WFMs use only one common (shared) audit trail for recording audit trail information; some of them allow the user to specify the properties of the audit trail.
[0061] A first most important observation is, that the prior art approach creates contentions on the audit trail if the workflow management system exploits parallel processing of different process instances to speed up the execution of business processes. In this case, the parallel executing process instances compete for the (shared) audit trail, which decreases the parallelism as all process instances need to get access to the audit trail. The present invention proposes to have multiple audit trails which provide for less overall contention by limiting any remaining contention to the individual audit trails.
[0062] A second important observation for the prior art approach can be made with respect to the size of the audit trail. The larger the audit trail gets, the more time and resources it takes to insert new audit trail records and to remove audit trail records. By having multiple audit trails, the size of the individual audit trails is much smaller, making insertion and removal of audit trail records much more efficient.
[0063] As already pointed out, the present invention suggests having multiple audit trails. A general approach to solving the above mentioned problems would suggest an audit trail distribution strategy assigned to the WFMS. The distribution strategy is based upon a specification of which said potential audit trails are actually used for writing an audit trail record. The distribution strategy is then dynamically analyzed during runtime for determining the concrete audit trail to be used for writing a current audit trail record.
[0064] It further suggests having two mechanism for selecting which audit trail to use in a particular situation: the server-controlled audit trail selection mode and the model-controlled audit trail selection mode. In the server-controlled audit trail selection mode, the workflow management system automatically assigns a particular audit trail to one or more server instances. In the model-controlled audit trail selection mode, the process modeler specifies for each process model or even each activity within a process model, which particular audit trail should be used for audit trail records generated.
[0065] In the following example the support of multiple audit trails either controlled via server specification or by model specifications is illustrated.
[0066] [0066]FIG. 1 shows a particular system structure of a workflow management system that provides for the parallel processing of process instances. It is set up as a message-based application server, that consists of a set of execution server instances (execution servers, for short) ( 100 ) running in parallel; all of them processing process instances. New requests for the workflow management system are provided by clients ( 120 ) putting messages into a queue ( 130 ) from which all execution servers are reading. The client ( 120 ) can also be another component of the workflow management system or even an execution server. The audit trails generally reside in some store ( 110 ) either persistent or non-persistent. It should be noted that the system structure shown in FIG. 1 serves only as an example; any other system structure that provides for parallelism can be exploited via the present invention.
[0067] [0067]FIG. 2 shows the definition of the properties for an audit trail. It should be noted that in all figures of this description the Flow Definition Language (FDL) of MQSeries Workflow is used; any other language, textual as well as graphical, could be used instead. The keyword AUDIT_TRAIL ( 200 ) starts the definition for an audit trail; the name of the audit trail is Audit1 ( 210 ). The keyword TABLE_NAME ( 220 ) indicates that the audit trail is managed as a table in a relational database management system; the name of the table is FMCTB01. The keyword DATABASE ( 240 ) indicates the database the table is in; the database name is FMCDBL ( 250 ). It should be noted that it is not required that the audit trails are defined as a separate entity; any other method will do it.
[0068] [0068]FIG. 3 shows the definition of the default audit trail; the specified audit trail will be used when no specific audit trail is specified in an AUDIT statement associated with a process model or an activity in a process model. It should be noted, that the capability of being able to define a default audit trail is not necessary for the present invention to work; it's provided here for completeness, as a workflow management system would need to provide this for ease-of-use. The keyword SYSTEM ( 300 ) is used to define the properties of an instance of a workflow management system; the name of the instance is System1 ( 310 ). The keyword AUDIT_TRAIL ( 320 ) defines the default audit trail; the name of the audit trail is Audit1 ( 330 ). It should also be noted that this definition is only required for model-controlled audit trail selection as a method to refer from definitions within the process model to this definition by the audit trail name Audit1.
[0069] Server-Controlled Audit Trail Selection
[0070] In the server-controlled audit trail selection mode, each of the defined audit trails is assigned to zero, one, or more instances of the execution server (as shown in FIG. 1). The method of assigning of an audit trail to a server instance can be defined by the user.
[0071] [0071]FIG. 4 shows an example of the definition of the properties of the execution server and in particular the definition of the audit trails to be used in server-controlled audit trail selection. The keyword SERVER ( 400 ) starts the definition of a server, in this case named MultiAuditServer ( 410 ). The keyword TYPE ( 420 ) starts the definition of the type of server, the parameter EXECUTION_SERVER ( 430 ) defines this server as an execution server; that means the server that performs navigation and execution of process instances. The keyword AUDIT ( 440 ) is used to define the list of audit trails, that should be used in server-controlled audit trail selection, namely Audit1, Audit2, and Audit 3 ( 450 ). The keyword AUDIT_DISTRIBUTION ( 460 ) defines the method of assigning audit trails to execution server instances. The specification of ROUND_ROBIN ( 460 ) indicates that the assignment is round robin. If, for example, the execution server runs four instances ES1, ES2, ES3, and ES4. Then Audit1 would be assigned to ES1 and ES4, Audit2 to ES2, and Audit3 to ES3. Of course other distribution strategies are possible instead of round-robin.
[0072] A major advantage of the server-controlled audit trail selection is the same utilization of all audit trails. The major disadvantage of this approach is the scattering of audit trail records of the same process instance over all audit trails making the analysis of the audit trail more cumbersome.
[0073] Model-Controlled Audit Trail Selection
[0074] In the model-controlled audit trail section mode, the process modeler specifies for process models or even activities within a process model the audit trail that should be used for writing audit trail records.
[0075] [0075]FIG. 5 shows an example of the definition of an audit trail on the process level. The keyword PROCESS ( 500 ) starts the definition of a process model LoanProcess ( 510 ). The keyword AUDIT ( 520 ) which defines the amount of audit trail information written as known from prior art (the specification of CONDENSED ( 530 ) request a condensed audit trail) is augmented according to the present invention with an AUDIT_TRAIL keyword ( 540 ). The AUDIT_TRAIL keyword indicates which audit trail should be selected for writing audit trail records; in the example, audit trail records should be written to the audit trail Audit1 ( 540 ).
[0076] [0076]FIG. 6 shows how the audit definition can also contain context based selection criteria based on the runtime evaluation of an evaluatable expression. The STRUCTURE ( 600 ) keyword defines a data structure LoanProcessData ( 605 ) which consists of a field LoanAmount ( 650 ). The actual definition of the process LoanProcess ( 610 ) starts with the keyword PROCESS ( 655 ); the data structure LoanProcessData ( 615 ) is used as input container.
[0077] The AUDIT keyword ( 620 ) is associated with two audit trail sub-specifications: one with a context based selection criteria ( 630 ), a corresponding audit volume parameter FULL ( 625 ), and an associated audit trail of Audit1 ( 635 ); the other with just an audit volume parameter CONDENSED ( 640 ) and an associated audit trail of Audit 2 ( 645 ). According to this definition of the process, a full audit trail is written to audit trail Audit1 for loan processes with a loan amount exceeding $10.000; a condensed audit trail is written to audit trail Audit2 for all other business process instances.
[0078] In FIG. 7 a further embodiment is shown, enhancing the example of the embodiment of FIG. 5, where model-based audit trail selection is applied to the activity level. For this purpose an audit trail specification, identified via the AUDIT keyword ( 725 ), is added for the activity CollectCreditInformation ( 730 ) which is identified via the PROGRAM_ACTIVITY keyword ( 750 ). The audit trail volume parameter FULL ( 735 ) indicates that a full audit trail should be written and the AUDIT_TRAIL=Audit2 ( 740 ) specification indicates that the appropriate audit trail records should be written to the audit trail Audit2. As a consequence of the audit definitions, a condensed audit trail is written to audit trail Audit1 for all activities except the CollectCreditInformation activity for which a full audit trail is written to the audit trail Audit2.
[0079] [0079]FIG. 8 enhances the example given in FIG. 7 by adding a context based selection criteria ( 835 ) that causes the full audit trail for the CollectCreditInformation activity only to be written when the loan amount exceeds $10.000 (based on the runtime evaluation of an evaluatable expression).
[0080] The model-controlled audit trail selection has the major advantage that the audit trail information for business processes can be kept together in one audit trail (unless explicitly specified by the process modeler) making the analysis of the audit trail simple and easy manageable. On the other hand this may possibly result in an unequal utilization of the various audit trails depending on the execution frequency of individual process models or program activities.
[0081] The present invention can be realized in hardware, software, or a combination of hardware and software. A WFMS according to the present invention can be realized in a centralized fashion in one computer system, or in a distributed fashion where different elements are spread across several interconnected computer systems. Any kind of computer system—or other apparatus adapted for carrying out the methods described herein—is suited. A typical combination of hardware and software could be a general purpose computer system with a computer program that, when being loaded and executed, controls the computer system such that it carries out the methods described herein. The present invention can also be embedded in a computer program product, which comprises all the features enabling the implementation of the methods described herein, and which—when loaded in a computer system—is able to carry out these methods.
[0082] Computer program means or computer program in the present context mean any expression, in any language, code or notation, of a set of instructions intended to cause a system having an information processing capability to perform a particular function either directly or after either or both of the following a) conversion to another language, code or notation; b) reproduction in a different material form. | Proposed is a mechanism for writing audit trail records in a Workflow-Management-System (WFMS) which comprises the steps of:
Assigning a multitude of audits trails as potential targets for audit trail records to said WFMS, and
Assigning an audit trail distribution strategy to said WFMS, comprising a specification which of said potential targets to be used for writing an audit trail record, and
Dynamically analyzing for a current audit trail record said distribution strategy and determining a current target from said multitude of audit trails, and
Writing said current audit trail record to said current target.
By the proposed mechanism the contention on the audit trail is reduced. Therefore by implementing the present invention the response time of requests, processing time of process instances, and the throughput of the WFMS is improved. | 6 |
BACKGROUND OF THE INVENTION
The present invention relates to a spark ignition internal combustion engine for automobiles, having a system for controlling the emission of noxious gases from the exhaust comprising the combination of a plurality of devices including an after burner for the exhaust gases, the function of which is to reduce the amount of carbon monoxide and unburnt hydrocarbons in the exhaust gases, means for improving the carburation when the engine is cold (this means also functioning to improve the fuel consumption when the engine is hot), means for recycling at least part of the exhaust gases to the induction side of the engine, and means for reducing the emission of pollutants during deceleration of the engine.
In an attempt to reduce atmospheric pollution many countries now have laws which require internal combustion engines to be fitted with various devices for the purpose of reducing, as far as possible, the emission of pollutants, and for improving the fuel consumption. In order to comply with these laws many automobile manufacturers fit their vehicles with after burner means for effecting further combustion of the exhaust gases by admitting into the exhaust system further combustion air so that the combustion of carbon monoxide and hydrocarbons is as complete as possible. Further measures include the addition into the fresh fuel/air mixture which is about to be burnt a small part of the hot exhaust gases, which thus reduces the formation of oxides of nitrogen, and the introduction of supplementary air into the induction manifold during deceleration of the engine whereby to reduce the fuel content in the fuel/air mixture thereby reducing the emission of unburnt hydrocarbons which are an important part of the pollutants in the exhaust gases emitted in these conditions.
However, in certain transitional operating conditions of an internal combustion engine some of the above mentioned measures can cause engine operating difficulties, particularly during starting of the engine, and in running conditions when the engine is cold.
OBJECTS OF THE INVENTION
A primary object of the present invention is a system for reducing as much as possible the emission of noxious gases from an internal combustion engine.
Another object of the invention is a system for reducing the emission of noxious gases from an internal combustion engine which, while achieving the above stated object, also encourages good behaviour of the engine during all operating conditions.
SUMMARY OF THE INVENTION
The above stated objects are achieved, according to the present invention by a spark ignition internal combustion engine having an exhaust emission control system including means for admitting air into the engine exhaust system, said means being constituted by; automatic unidirectional valve means communicating with the exhaust duct of said engine, an air pump mechanically connected to said engine whereby to be driven thereby when said engine is operating, air conduit means interconnecting said air pump and said automatic unidirectional valve means which latter is mounted on the cylinder head of the engine, means defining an internal passageway in said cylinder head, said internal passageway communicating at one end with said automatic unidirectional valve means and at the other end with said exhaust duct, and pressure relief valve means in said air conduit means operating to release excess air pressure generated by said airpump during operation of said engine.
Other features and advantages of the invention will become apparent from reading the following description, in which reference is made to the single FIGURE of the accompanying drawing, provided purely by way of non-restrictive example.
BRIEF DESCRIPTION OF THE DRAWING
The single FIGURE of the accompanying drawing is a schematic diagram illustrating the novel exhaust emission control system of the present invention adapted for use with an internal combustion engine of a type suitable for an automobile, which engine is also shown, in very diagrammatic form, in the drawing.
DESCRIPTION OF THE PREFERRED EMBODIMENT
In the drawing there is shown, generally indicated with the reference numeral 1, an internal combustion engine having an induction system including a double body carburettor 10 and an induction manifold 9, and an exhaust system which includes a catalytic silencer of the oxidising and insulated type. The exhaust system of the engine 1 includes an exhaust manifold 7 provided with an exhaust gas take-off point 3 from which exhaust gases are drawn for exhaust gas recycling by an exhaust gas recycling system which includes a valve 4 of known type, for example one which is sensitive not only to the variation of a control pressure at a control inlet thereof, but is also sensitive to back pressure at the inlet; such a valve is usually termed an E.G.R. (Exhaust Gas Regulation) valve. The EGR valve 4 has an inlet connected by a duct 5 to the gas take-off point 3 in the exhaust manifold 7, and an outlet connected by a duct 6 to an inlet 8 on the induction manifold 9 of the engine, located at a point downstream of the carburettor 10. The control inlet of the valve 4 receives a vacuum signal through a duct 12 which communicates, through a hole 13 in the body of the carburettor, with the interior of the induction duct at a point located upstream of the butterfly of the first body of the carburettor 10. As mentioned above, switching of the valve is dependent not only on the vacuum signal in the duct 12 but also on the value of the back pressure existing in the exhaust duct.
A normally closed temperature sensitive valve 14 of known type is located in series in the duct 12. This valve 14 is positioned so that it can sense the temperature of the coolant fluid of the engine 1 and acts to close off the pneumatic valve 4 from the signal vacuum to prevent the pneumatic valve 4 from passing exhaust gas to be recycled, whilst the engine coolant is below a certain threshold temperature.
On the cylinder head 15 of the engine, is located an automatic non-return valve 16 of known type, connected to the exhaust passages within the interior of the cylinder head 15 through a passage 17 in the cylinder head. This automatic non-return valve is also connected by a duct 20 to an air pump 18 driven by the engine; the duct 20 is connected by a duct 22 to a pressure release valve 24 in the top of an air filter 26. The pressure release valve 24 serves to allow the escape of excess air provided by the air pump 18 of the engine. The pump 18, driven by the engine, delivers fresh air via the duct 20 to the automatic non-return valve 16 which feeds it into the exhaust passages leading from the cylinders of the engine, for the purpose of obtaining further combustion (after burning) of the incompletely burnt gases which are discharged from the combustion chambers of the cylinders, whereby to reduce the content of noxious pollutants in the exhaust gases.
To the inlet 8 on the induction manifold 9 (to which the outlet of the EGR valve 4 is connected) there is also connected, by means of a duct 28, a pneumatic valve 30 of known type, commonly termed a "gulp" valve, which forms part of an arrangement acting to admit a flow of supplementary air into the induction manifold of the engine during deceleration conditions. The "gulp" valve has a large diameter air inlet covered by an air filter 39, and an outlet connected by a duct 28 to the inlet opening 8 in the induction manifold 9. Communication between the inlet and outlet is controlled by a valve shutter (not shown) controlled by a diaphragm (also not shown) which separates the interior of the valve into an upper chamber and a lower chamber, both of which chambers have respective inlets thereto. As is known, when the pressure in the upper chamber is lower than that in the lower chamber the diaphragm moves upwardly carrying with it the valve shutter thereby closing communication between the inlet and the outlet valve. Correspondingly, when the pressure in the lower chamber is lower than that in the upper chamber, the diaphragm moves downwardly to open the valve.
The arrangement for admitting supplementary air to the induction manifold also includes means for preventing this flow of supplementary air during starting conditions and when the engine is cold in order to avoid various problems which would otherwise arise during these conditions. The arrangement includes a three way, two position solenoid valve 32 the excitation winding of which is connected to the starter motor 34 of the engine. The solenoid valve 32 has three ports one of which is connected by means of a duct 35 to a hole 36 in the induction duct whereby to communicate with the interior thereof at a point downstream from the butterfly valve of the carburettor 10; the second port of the solenoid valve 32 is connected by a duct 37 to the upper chamber of the valve 30 and the third port of the solenoid valve 32 is connected to the lower chamber of the "gulp" valve by means of a duct 38. The arrangement operates as follows:
The "gulp" valve 30 is closed when its diaphragm is drawn upwards by a vacuum in the upper chamber of the valve and is open when its diaphragm is drawn downwardly by a vacuum in the lower chamber. Resilient or other biasing means urges the diaphragm upwardly to the closed position of the valve so that a vacuum in the lower chamber must exceed a certain threshold value before the valve is opened. The magnitude of this threshold can be selected by suitable selection of the diaphragm biasing. When the winding of the solenoid valve 32 is not excited the duct 35 is put into communication by solenoid valve 32 with the duct 38 and therefore with the lower chamber of the "gulp" valve 30. Thus when the vacuum in the induction manifold, and therefore in the duct 35 is sufficiently high, as occurs in the case of deceleration of the engine, the diaphragm of the "gulp" valve 30 is drawn downwardly whereby to open this valve, allowing a flow of supplementary air to pass into the induction manifold, this air being filtered in the air filter 39. This admission of supplementary air to the induction manifold serves to weaken the fuel/air mixture before it enters the combustion chambers of the engine thereby reducing, to some extent, the peaks of emission from the exhaust system of unburnt hydrocarbons, which peaks occur during deceleration; the admission of supplementary air to the induction manifold also helps to prevent the occurrence of small explosions or popping due to backfiring in the exhaust system. The admission of supplementary air to the induction manifold would be dangerous, and possibly damaging to the engine, however, when the engine is running cold, that is during and immediately after starting, before it has warmed up to its normal operating temperature. The invention avoids this disadvantageous possibility in the following manner:
A battery 40 is connected to the winding of the starter motor 42 via a switch 44. The excitation winding of the solenoid valve 32 is connected to the winding of the starter motor 34 by an electrical conductor 46, and directly to the battery 40 by a conductor 48 in which is located a temperature sensitive switch 50 positioned at a point on the engine where it can sense the temperature of the engine coolant fluid. Temperature sensitive switch 50 is closed when the temperature of the engine coolant fluid is below a certain threshold value and opens when the temperature increases above this threshold.
Upon starting of the engine the solenoid valve 32 is excited via the conductor 46, whilst when starting is accomplished, with the switch 44 open, and with the motor cold, the solenoid valve 32 is excited via the conductor 48, and the temperature sensitive switch 50 which in these conditions is closed. When the solenoid valve is excited it puts the duct 35 into communication with the upper chamber of the "gulp" valve 30 instead of the lower chamber, so that the "gulp" valve 30 is now held firmly closed and no flow of air can pass through it to reach the induction manifold whatever the value of the depression existing therein. When the engine coolant warms up to a selected threshold value the temperature sensitive switch 50 responds to this by opening thereby interrupting the connection to the solenoid valve 32 so that this latter becomes de-energised and therefore puts the duct 35 into communication with the lower chamber of the "gulp" valve 30 so that when the vacuum in the manifold rises above a certain threshold, which it does upon deceleration, the valve 30 opens to admit supplementary air as described above.
The carburettor 10 is fitted with an additional pneumatic valve 52 (shown diagramatically as a box separated from the carburettor in the drawing) which forms part of a system termed a "power valve", connected to the duct 35 by means of a duct 51. A normally closed temperature sensitive valve 53, sensitive to the temperature of the engine coolant fluid, is connected in series in the duct 51. The pneumatic valve 52 of the "power valve" system is activated when the vacuum in the induction manifold is below a predetermined threshold, and in these conditions it enriches the mixture. This enrichment of the mixture in low vacuum conditions only constitutes an improvement in engine operating conditions when the engine is cold, however, and would deleteriously affect the fuel consumption if it continued when the engine was hot. The temperature sensitive valve 53 in series in the duct 51 operates therefore to inhibit the operation of the pneumatic valve 52 by closing off its communication with the duct 35 when the temperature of the engine coolant rises above a predetermined threshold value, so that the pneumatic valve 52 is then no longer sensitive to the vacuum in the induction manifold, and thus does not deliver any supplementary fuel, whatever the vacuum in the manifold, once the engine has attained the threshold temperature.
As well as the pneumatic valve 52 of the "power valve" system the carburettor 10 also incorporates a pneumatic pump 54 (also shown separated from the carburettor in the drawing) which is a secondary compensation pump. This pump is also connected to the duct 35 by means of a duct 55 in which is located, in series, a temperature sensitive valve 57 which is open when the engine is cold and is sensitive to the temperature of the engine coolant. The pneumatic pump 54 works by delivering supplementary petrol when there is a strong variation of depression in the induction manifold, but only when the engine is cold, since when the engine is hot the temperature sensitive valve 57 closes and the pneumatic pump 54 remains inactive; this has the effect of reducing pollution by the engine when it is hot, whilst nevertheless ensuring that the engine operating conditions are optimum when the engine is cold.
Upstream of the butterfly of the carburettor 10 there is a hole 60 which is connected in a known way, by means of a duct 62, to the pneumatic advance and retard capsule which adjusts the ignition timing of the ignition distributor 66 in dependence on the vacuum in the induction system of the engine, which in turn is dependent on the combination of throttle opening and engine speed.
It will be appreciated that all the temperature sensitive valves which are shown in different locations around the system illustrated in the drawing would in a practical embodiment of the system be conveniently regrouped in a single centralised control unit where they can be in good thermal contact with the engine coolant fluid. | A spark ignition internal combustion engine having an exhaust emission control system including an air pump driven by the engine to pump fresh air directly into the exhaust duct in order to promote a further combustion of partly burnt components in the gases coming from the combustion chambers, excess air pressure being released by a pressure relief valve into an air filter for the induction air; the system also comprises an exhaust gas recirculating system comprising a pneumatic valve which opens, when the conditions are appropriate, to draw off a proportion of the exhaust gases from the exhaust side of the engine and admit them to the induction side of the engine; in addition there is a system for admitting supplementary air to the induction manifold downstream of the carburettor during engine overrun conditions except when the engine is cold, and the carburettor is provided with supplementary pumps and valves which only function when the engine is cold, being inhibited as the engine approaches its normal working temperature. | 5 |
RELATED APPLICATIONS
[0001] This application is a continuation-in-part of U.S. patent application Ser. No. 09/431,060, entitled OPTICALLY REFLECTIVE SLEEVING AND ASSOCIATED METHODS OF USE, which was filed Nov. 1, 1999.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to sleeving products commonly used to bundle cables, protect hoses and organize wires. More particularly, the present invention relates to sleeving products made from specialty materials that provide the sleeving products with useful optical properties.
[0004] 2. Description of the Prior Art
[0005] Protective sleeving is an auxiliary sheathing structure that can be passed over wires, tubing, cable or any other elongated structure. When protective sheathing is placed over tubing, cables or like structures, its primary purpose is to protect those structures from damage due to contact abrasion and other wear. When protective sleeving is placed over loose wires, its primary purpose is to bind the wires into an organized cable while protecting those wires from damage.
[0006] In the prior art, there are many different types of protective sleeving. A common type of protective sleeving is expandable sleeving. Expandable sleeving is made of braided strands of material. When braided sleeving is compressed, its diameter expands. Likewise, when braided sleeving experiences tension, the diameter of the braided sleeving contracts. Accordingly, braided sleeving is very useful in protecting segments of wire and tubing that may vary in diameter from point to point.
[0007] The material used to produce expandable sleeving varies with technical requirements. In applications where the expandable sleeve will experience extreme conditions, the expandable sleeve is often made from braided metal wire, such as stainless steel. In applications where the expandable sleeve experiences normal conditions, the expandable sleeves are most commonly fabricated from strands of polymer filaments, such as polyester yarn, polyethylene terephthalate, Teflon®, Ryton®, Nylon® and the like.
[0008] Since protective sleeving acts as the cover to many elongated structures, in many applications the protective sleeving is the only part of the structure that is visible to an observer. Accordingly, in an attempt to enhance the appearance of many assemblies, the aesthetics of the protective sleeving has been altered. For example, protective sleeving made from polymer filaments can be fabricated in any color of the spectrum by adding dye to the polymer being used. Protective sleeving made from metal wire can be chromed, anodized or otherwise colored for aesthetic purposes. Such techniques are exemplified in U.S. Pat. No. 5,639,527 to Hurwitz, entitled, Braided Wire Sheathing Having Chrome Appearance.
[0009] An example of an assembly where the protective sleeving is highly visible is a bicycle. Many bicycles have brake cables. The brake cables are often covered with a protective sleeving to prevent damage to the brake cables. The protective sleeving is visible to any person viewing the bicycle. As such, the aesthetics of the protective sleeving are important to the overall appearance of the bicycle.
[0010] It is known to make protective sleeving for assembles, such as bicycles, from different color material. However, it is a purpose of the present invention to provide protective sleeving that is not only aesthetically pleasing but also provides reflective optical properties. Consequently, not only is the protective sleeving aesthetically pleasing, it acts a reflector at night, thereby providing safety to the assembly and greatly increasing the night time aesthetics of the assembly.
SUMMARY OF THE INVENTION
[0011] The present invention is a reflective protective sleeve. The protective sleeve is formed into a tubular structure, wherein the protective sleeve defines an internal surface and an exterior surface. The sleeve is made from plastic monofilaments that are braided together. All the monofilaments are uniformly made of plastic. However, the plastic used to fabricate at least most of the monofilaments in the sleeve are fabricated from optically reflective plastic. Accordingly, the protective sleeve embodies optically reflective properties that makes that sleeving highly visible at night when in range of the headlights of an approaching vehicle.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] For a better understanding of the present invention, reference is made to the following description of exemplary embodiments thereof, considered in conjunction with the accompanying drawings, in which:
[0013] [0013]FIG. 1 is perspective view of an exemplary embodiment of a reflective sleeve shown covering the brake cables of a bicycle;
[0014] [0014]FIG. 2 is perspective view of a section of a bicycle brake cable covered with a segment of a reflective protective sleeving; and
[0015] [0015]FIG. 3 is a perspective view of an embodiment of the present invention having a closable seam.
DETAILED DESCRIPTION OF THE INVENTION
[0016] Although the present invention protective sleeving can be used to protect most any cable, tube or wire bundle in a wide variety of assemblies, the present invention is particularly well suited for use in covering the brake cables of a bicycle. Accordingly, by way of example, the present invention device will be described in an application where the device is used to cover the brake cables of a bicycle. The application described is merely exemplary and should not be considered a limitation to the applications of the present invention protective sleeving device.
[0017] Referring to FIG. 1, a bicycle 10 is shown. The bicycle 10 has a hand brake system. The hand brake system uses levers 12 on the handlebars 14 to manipulate wire brake cables 16 . The wire brake cables 16 extend to the clamp brakes 18 on the wheels of the bicycle 10 . Each of the brake cables 16 contain a metal cable surrounded by a plastic sheathing. When the levers 12 on the handlebars 14 are manipulated, the metal wire moves in relation to its plastic sheathing, thereby causing the clamp brakes 18 to operate. The present invention protective sleeving 20 covers the cable sheathing, thereby providing an added layer of protection from contact damage.
[0018] The protective sleeving 20 is made of strands of optically reflective plastic. There are many compositions of optically reflective plastic. Optically reflective plastics are plastics that reflect, at random angles of reflection, a high percentage of light energy that strikes the plastic. Compositions of optically reflective plastic are used in the formation of automobile and bicycle reflectors. Such reflectors reflect light of headlights at night, thereby making the reflectors visibly noticeable to on coming traffic. Any of the compositions of optically reflective light plastic that is used in the field of reflector plastic production can be adapted for use in the present invention.
[0019] In the embodiment of FIG. 1, the stands used to make the protective sleeving 20 are completely and uniformly molded from the optically reflective plastic. Accordingly, when a light strikes the bicycle at night, the light is reflected by the material of the protective sleeving 20 . This causes the reflective sleeving 20 to appear to glow.
[0020] The protective sleeving 20 extends across a significant portion of the frame of the bicycle 10 . Accordingly, at night, the protective sleeving 20 can more than double the reflective surfaces of a normal bicycle. Furthermore, reflectors are commonly mounted to the front, rear and pedals of a bicycle. The reflective protective sleeving 20 can be viewed from the front, rear and sides of the bicycle, thereby greatly increasing the visibility of the bicycle 10 , especially when viewed from the side.
[0021] The presence of the reflective protective sleeving 20 on the bicycle's brake cables 16 also enables a person to visualize the length of the bicycle 10 as it passes in the night. This provides automobile drivers with a greater perception of the size and location of the bicycle 10 , thereby reducing the chances of an accident.
[0022] Referring to FIG. 2, a first embodiment of the protective sleeving 20 is shown. In this embodiment, the protective sleeving 20 is made from braided plastic monofilaments. Each monofilament has a diameter of between 0.005 inches and 0.030 inches and is uniformly composed of plastic. Either all of the monofilaments or at least most of the monofilaments are uniformly and entirely fabricated from optically reflective plastic. The monofilaments that are fabricated from the optically reflective plastic are herein referred to as optically reflective monofilaments.
[0023] As was previously explained, the plastic compositions used in creating the optically reflective monofilaments can be any of the reflective plastic materials currently used in the production of standard bicycle light reflectors. Extenders and plasticizers can be added to the plastic composition, prior to forming the monofilaments, in order to increase the elasticity of the optically reflective monofilaments so that the flexibility of the optically reflective monofilaments is close to that of the standard braiding monofilaments. The addition of such extenders and plasticizers do not have significant adverse effects on the optically reflective properties of the plastic.
[0024] As is known in the prior art, optically reflective plastic can be made into numerous colors. The most common colors of reflective material are red, yellow and white. As such, it should be understood that the optically reflective monofilaments used in the braiding of the protective sleeving 20 can be made in numerous colors. Accordingly, a person can select the color of the protective sleeving 20 . In this manner, a color can be selected that will not clash with the colors of the bicycle when viewed during the day.
[0025] The optically reflective monofilaments and the standard monofilaments, if any, are braided in a traditional manner to make the reflective protective sleeving 20 . To apply the reflective protective sleeving 20 to a bicycle, a segment of protective sleeving 20 is cut to a length that matches that of a particular brake cable. The brake cable 16 is then disconnected from the bicycle at at least one end. The protective sleeving 20 is advanced over the brake cable 16 until the protective sleeving 20 extends along the length of the brake cable 16 . The brake cable 16 is then reattached to the bicycle.
[0026] It is understood that the illustration of a bicycle is merely exemplary and that the reflective protective sleeving can be applied over most any cable, tube or gathering of wires. In certain application, it may not be practical to disconnect a tube, cable or group of wires in order to install the reflective protective sleeving. In such scenarios, the reflective protecting sleeving can be fabricated with a seam.
[0027] Referring to FIG. 3, a segment of reflective protective sleeving 30 is shown. In this embodiment, the protective sleeving 30 has a seam 32 that runs the length of the protective sleeving 30 . Hook and loop fastening material 34 is positioned adjacent the seam 32 . The hook and loop fastening material 34 enables the reflective protective sleeving 30 to be selectively closed around an elongated structure 36 without having to disturb the elongated structure 36 . The hook and loop fastening material 34 is not present on the exterior of the protective sleeving 30 when the protective sleeving 30 is closed. Consequently, the reflective properties of the protective sleeving 30 are undisturbed by the seam 32 or the hook and loop material 34 .
[0028] It will be understood that the specifics of the present invention described above illustrate only exemplary embodiments of the present invention. A person skilled in the art can therefore make numerous alterations and modifications to the shown embodiments utilizing functionally equivalent components to those shown and described. Furthermore, features of the different embodiments can be mixed and matched in ways not specifically described. All such modifications are intended to be included within the scope of the present invention as defined by the appended claims. | A reflective protective sleeve structure having a tubular a tubular structure, wherein the protective sleeve defines an internal surface and a reflective exterior surface. The sleeve is made from plastic monofilaments that are braided together. All the monofilaments are uniformly made of plastic. However, the plastic used to fabricate at least most of the monofilaments in the sleeve are fabricated from optically reflective plastic. Accordingly, the protective sleeve embodies optically reflective properties that make that sleeving highly visible at night when in range of the headlights of an approaching vehicle. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a method for enhancing the metallurgical quality of products treated in a furnace, and especially a reheat furnace. This invention applies to any type of product, but more particularly to products treated in a reheat furnace, such as, for example, billets, blooms, slugs or slabs, or any other product used by iron and steel manufacturers in their production line (such as sheet or plate, tube, etc.). The invention relates more particularly to a method of treating a metallurgical product in a furnace, in which the product be treated is introduced into the furnace and then subjected to the desired treatment before being removed from the furnace, the furnace comprising heating means and especially burners for raising the various zones of the furnace to a variable temperature, it being possible for the atmosphere in these various zones to have an identical or different composition depending on the zones in question of said furnace.
2. Related Art
The environment of a steel (or any other product, especially a metal or iron or steel product), when it is raised to a high temperature during a heat treatment, is often an atmosphere which is oxidizing with respect to the metal. This situation may result, on the one hand, in oxidation of the metal with the formation of a surface layer of scale and, on the other hand, in decarburization of the steel with the creation of a carbon concentration gradient near the surface of the workpiece.
The altered region at the surface of these workpieces is essentially composed of two parts (see FIG. 1 ), one lying on the atmosphere side (upper scale) and the other adjacent the metal (hybrid region).
The upper part generally is composed of three dense oxide layers: a layer of oxide Fe 2 O 3 (hematite), which is very thin (with a thickness of a few microns), a layer of magnetite (Fe 3 O 4 ) (about 4% of the total scale) and a thick layer of the oxide FeO (wustite) (about 95% of the total scale) which is of greater or lesser porosity depending on the reheat time and the reheat temperature.
The growth of this scale, which follows a parabolic law, is controlled by the diffusion of Fe 2+ ions into the wustite and the magnetite and by the diffusion of oxygen O 2 − into the hematite.
The lower part, or hybrid region, has a greater or lesser thickness depending on the nature of the steel. It is located at the metal/scale interface and consists of a mixture of FeO and products resulting from the reaction of FeO with the oxides of certain alloying elements. This lower part is also composed of a metal region altered by various phenomena, such as decarburization or internal oxidation. Decarburization is a phenomenon involving the solid-state diffusion of carbon, which reacts with the FeO scale (and/or H 2 O). The permeability of industrial scale to the gaseous products resulting from the oxidation of carbon (especially CO) makes this oxidation at the surface of the metal almost immediate. Decarburization is therefore limited by the diffusion of carbon at the treatment temperature and is favored by the ability of the gases formed (CO) to escape from the scale-steel interface.
Depending on the thermal profile imposed and on the composition of the atmosphere (especially the O 2 , H 2 O and CO 2 contents), the iron or steel products may be oxidized (scale) and decarburized (this being the more so in the case of high-carbon steels). In both cases, the steel manufacturer will have to subject his workpieces to an additional operation aimed at eliminating these surface defects. Whereas the oxide layer may be removed by various descaling techniques, the decarburized layer, that forms an integral part of the workpiece, cannot be easily “erased”: the surface of the product is devoid of some of its carbon atoms, thereby degrading the mechanical properties on the surface of the product (longevity, hardness, etc.).
The oxidation or decarburization of steel in a reheat furnace thus results in a loss of raw material, which is called “loss on ignition”, and a degradation of the surface properties of products, which are prejudicial to the steelmaker.
A major constraint, which will also affect the final quality of the product at the end of the reheat process, is the final temperature of the product and its thermal homogeneity, this being so whatever the heating history that has taken place in the furnace (time spent at certain temperature levels, slower production rate following a rolling mill incident, etc.). Any lack of thermal inhomogeneity will cause structural defects and a posteriori mechanical embrittlement of the finished products. These defects may also cause certain parts of the rolling mill (especially rolling-mill stands) to be stopped or even broken.
Any optimization of the metallurgical quality of the product must meet this constraint with regard to the thermal homogeneity of the product. During operation of the furnace by the operator, control of and compliance with the temperature rise of the product are key factors in ensuring in the end that the thermal homogeneity constraint is met.
A person skilled in the art knows that, to avoid decarburization and oxidation, it is recommended to work in a protected atmosphere by substoichiometric combustion (using a fuel-rich mixture generating a neutral or even reducing atmosphere with respect to steel). This method is employed in galvanizing processes (see, for example, Galvanisation et aluminiage en continu [Continuous galvanizing and aluminizing] by E. Buscarlet, Technique de l'ingénieur [Engineering Techniques], 1996.
It is also known, from U.S. Pat. No. 4,415,415, to treat products in an atmosphere containing at least 3% oxygen by volume, and to do so over the entire length of the furnace, thereby inevitably resulting in the formation of scale but making it possible to control the quality of the scale, which, under these conditions, becomes non-adherent and easily removable.
Patent EP-A-0 767 353 also proposes to vary the furnace atmosphere by zoning the furnace, that is to say by isolating the furnace into several chambers within which a highly oxidizing atmosphere is recommended, so as to be able to control the formation and quality of the scale. In this case, the loss on ignition is not reduced, but on the contrary is increased, only the quality of the scale being controlled.
The various methods known from the prior art therefore suggest that the products either be treated in an oxidizing atmosphere or in a reducing atmosphere.
The use of these various methods also has an additional drawback in the case of the treatment of steel products. This is because it is important to be able to measure the oxidizing or reducing character of the atmospheres involved. The only information available during implementation of these processes is provided by measurement probes located either in the roof, that is to say far from the surface of the products, or in the flue of the furnace. These measurements are therefore not representative of the composition of the atmosphere which interacts directly with the product. In general, the only measurable parameter of the atmosphere is the oxygen content. This information is generally insufficient—because the fact that the amount of oxygen in the smoke leaving the furnace is zero does not necessarily mean that the furnace atmosphere in contact with the metal workpieces is reducing with respect to steel (see, for example, Combustion Engineering and Gas Utilisation , published by British Gas, 1992, page 23). According to the Applicant, the species H 2 O and CO 2 also have an oxidizing role on the charge and are involved in scale formation reactions and in decarburization mechanisms. At the present time, it is not known how to measure these species simply and quickly.
To operate the furnace and meet the final constraint of thermal homogeneity of the product, the operator adopts an initial temperature profile of a given product for a given furnace, depending on the type of charge and of production. This profile is either known to the operator, because of his know-how, or is calculated from charts, or else calculated using suitable software.
The only information available for the operator and/or the furnace operation software are the measurements delivered by one or more thermocouples located in the roof of the furnace. These thermocouples are placed far from the charge and are not representative of the heat flux received by the charge beneath the burners. It is therefore necessary to estimate the relationship which links the roof temperature (which is measured) and the temperature of the charge (useful information). This relationship is either empirical (based on the operator's know-how) or calculated using furnace operation software.
Not only is this measurement only an indirect measurement of the necessary information, but the estimated relationship may prove to be less and less accurate upon aging of the furnace, of the thermal characteristics of the various charges and variations in the type of fuel used.
Finally, this measurement is a measurement at a certain point, usually located on the axis of the furnace and it does not take into account possible variations in said parameter over the entire width of the furnace.
The fact of not having measurements made as close as possible to the product has the consequence that the characteristic times of the process for heating these products is not known exactly. Yet it has been found that these characteristics have a major influence on the oxidation and decarburization kinetics of said products, it being possible that an incorrect estimation of these times has serious consequences as regards the final metallurgical quality of the product.
SUMMARY OF THE INVENTION
The aim of the present invention is to provide a method of operating a furnace (temperature, composition of the atmosphere) and an associated control procedure, making it possible to optimize both the metallurgical quality of a product and the loss on ignition and thermal efficiency of a furnace.
FIGURES
For a further understanding of the nature and objects for the present invention, reference should be made to the following detailed description, taken in conjunction with the accompanying drawings, in which like elements are given the same or analogous reference numbers and wherein:
FIG. 1 shows an altered region at the surface of the workpiece which is essentially composed of two parts.
FIG. 2 shows a characteristic curve of the variation in temperature of the product as a function of time, controlled according to the method of the invention.
FIG. 3 shows the application of the invention to a reheat furnace.
FIG. 4 shows the control, according to the invention, of the temperature rise of the product.
FIG. 5 shows a curve of the temperature in a reheat furnace as a function of time.
FIG. 6 shows a curve of the variation in the amount of scale as a function of time.
FIG. 7 shows another curve of the variation in the amount of scale as a function of time.
DESCRIPTION OF PREFERRED EMBODIMENTS
The method according to the invention makes it possible to avoid the aforementioned drawbacks and allows the abovementioned aim to be achieved.
The method according to the invention is characterized in that the product to be treated has a temperature that increases between the moment when it is introduced into the furnace and the moment when it is removed therefrom, the temperature rise curve having a slope that increases over a first time interval between the time t 0 of introduction of the product into the furnace and the time t 1 at which the product achieves a surface temperature of 650° C., an approximately constant slope between the time t 1 and the time t 2 at which the product reaches a temperature about 15% below the desired final surface temperature of the product to be treated when it leaves the furnace, then a slope that decreases between the time t 2 and the time t 3 at which the product to be treated leaves the furnace, in which method the heating power of the furnace is increased relative to its power when only air/fuel burners are used, so as to increase the slope of the curve giving the rise in temperature of the product to be treated, at least during certain periods of treatment of the product in the furnace between the times t 1 and t 2 , thereby reducing the duration of the treatment of the product to be treated and correspondingly reducing the thickness of the decarburized layer and/or the layer of scale formed on the surface of the product.
Preferably, the increase in the heating power of the furnace is obtained by means of oxyfuel burners that constitute at least part of the heating means of the furnace, especially part of the heating means of the furnace corresponding to the zone reached by the product between the times t 1 and t 2 . It is also possible place this or these oxyfuel burners in a zone adjacent the abovementioned zone, which would make it possible for the same increase in power (in said zone reached by the product between the times t 1 and t 2 ) to be obtained indirectly.
In general, the oxidizer delivered to the oxyfuel burners, constituting at least part of the heating means of the furnace, contains at least 88% oxygen, preferably greater than 90% oxygen and even more preferably greater than 95% oxygen.
In general it is found that the time for treating the product between the temperatures of 700° C. and 800° C. reached by the surface of the product is reduced by 15% to 50% of its reference value, preferably by 20 to 35% of its value, whereas the treatment time between the temperatures of 700° C. and the final temperature of the surface of the product is reduced by between 3 and 25% of its reference value, preferably between 7 and 15% of its reference value.
Preferably according to the invention, used by itself or in combination with the other variants of the invention, the atmosphere of the furnace varies along the length of the furnace as a function of the skin temperature of the metallic product.
According to a first variant of the invention, used alone or in combination with the other variants of the invention, the atmosphere of the furnace on contact with the product to be treated contains about 0.5 to 5 vol % oxygen and preferably between 1.5 to 4 vol % oxygen when the skin temperature T at the surface of the treated product is greater than or equal to the equalization temperature T equalization , which is equal to 85% of the temperature at the surface of the product (discharge temperature) as it leaves the furnace. Preferably, the equalization temperature T equalization is equal to 90% of the discharge temperature.
According to another variant of the invention, used by itself or in combination with the previous ones, the atmosphere on contact with the product to be treated has an oxygen concentration of less than a few hundred ppm and a CO concentration of between 0.1 and 15 vol %, preferably 0.5 to 5 vol %, when the skin temperature T at the surface of the product is above 700° C. and below the equalization temperature of the product, defined as being equal to 90% of the skin temperature of the product as it leaves the furnace.
According to yet another variant of the invention, used by itself or in combination with the previous ones, the atmosphere in contact with the product to be treated has an oxygen concentration of between 0.5 and 4 vol % and preferably between 2 and 3 vol % when the skin temperature T at the surface of the product to be treated is below 700° C.
The invention allows the metallurgical quality of products to be optimized by optimizing the heating profile in the furnace together with improved control of the composition profile of the atmosphere in the furnace. This control continuously monitors the O 2 and/or H 2 O and/or CO 2 contents of the atmosphere in the various zones of the furnace, and/or the temperature at the surface of the products to be treated, will preferably be carried out using a diode laser. This TDL (Tunable Diode Laser) system makes it possible in fact to measure the average concentrations of gaseous species along the length of the optical path of the laser beam. For further details about diode lasers and in particular TDL-type diode lasers, reference may be made to the article by Mark G. Allen entitled “Diode Laser Absorption Sensors for Gas Dynamic and Combustion Flows”, Mes. Sci. Technology, 9, 1998, pages 545 to 562, and incorporated in the present text as reference. In general, these diode lasers are laser radiation sources, some of which operate at room temperature while others must be cooled. The laser beam emitted can in general be tuned within a wavelength range by varying the current injected into the laser source. All that is then required is to choose laser beam sources that can be tuned within wavelength ranges which correspond to at least one of the characteristic lines of the absorption spectrum of the species which it is wished to detect. Preferably, the diode laser will be placed near the surface of the products, at a distance varying between 1 mm and 15 cm, preferably between 2 cm and 6 cm. It is in the region of the surface of the product that the O 2 , H 2 O and CO 2 partial pressures thus of the temperature are involved in the mechanisms described above, namely scale formation and decarburization. This monitoring as close as possible to the surface also makes it possible for predictive tools to be developed and for the method proposed to be implemented properly.
A greater understanding of the invention will be gained from the following illustrative examples, given without implying any limitation, in conjunction with the figures which show:
FIG. 2 shows a characteristic curve of the variation in temperature of the product as a function of time, controlled according to the method of the invention;
FIG. 3 shows the application of the invention to a reheat furnace;
FIG. 4 shows the control, according to the invention, of the temperature rise of the product;
FIG. 5 shows a curve of the temperature in a reheat furnace as a function of time;
FIG. 6 shows a curve of the variation in the amount of scale as a function of time;
FIG. 7 shows another curve of the variation in the amount of scale as a function of time.
In FIG. 2 , the curve ( 21 ) represents the heat-up curve of the product, for example the skin temperature of a billet or of a slab in a reheat furnace. According to this curve, it is possible to define the times t 0 , t 1 , t 2 and t 3 corresponding, respectively, to the time t 0 when the product is introduced into the furnace, to the time t 1 when the skin temperature reaches 650° C., to the time t 2 when the skin temperature is equal to 85% of the final (or discharge) temperature T out of the skin of the product and, finally, to the time t 3 when the product is discharged at its final temperature T out . Thus, a time interval Δ 1 corresponding to the time that the surface of the product spends between t 1 and t 2 is defined. A time Δ 2 corresponding to the time spent by the product between t 1 and t 3 may also be defined.
The method according to the invention consists in reducing the time Δ 1 by about 8% to 40% of its reference value and preferably by about 10% to 30% of its reference value. This allows the thickness of the decarburized layer to be decreased by at least 20%, depending on the contents of the alloying elements and specifically the carbon content, compared with the method of the prior art using either the empirical operation of the furnace by an experienced person skilled in the art or the operation of the furnace using temperature charts or suitable software. It is in particular the reduction in the time Δ 1 , resulting in an increase in the slope of the curve 52 compared with the slope of the curve 51 between the times t 1 and t 2 corresponding to the temperatures of 650° C. and of 85% of the skin temperature at the exit of the furnace, which is fundamental according to the method of the invention, as it has been demonstrated that it is in these temperature ranges that it is necessary to increase the slope of the heat-up curve of the product if it is desired to obtain the hoped-for reductions.
Likewise, the invention makes it possible to reduce the time Δ 2 by between 5 and 30% of its reference value and preferably by between 7 and 15% of its reference value. This makes it possible to decrease the mass of the scale by between 5 and 30%, depending on the nature of the steel.
This reduction in the times Δ 1 and Δ 2 is achieved, according to the invention, by increasing the energy transferred to the product throughout the duration of its residence in the furnace. This may be achieved by increasing the available energy (by adding an energy source, via naked-flame burners, radiant tubes or else electrical resistance elements or induction heating) or by increasing the efficiency of the available energy (by enriching the combustion air up to, for example, oxygen, up to a purity of up to 100%), preferably to above 90 vol % Of O 2 .
The maximum reduction of Δ 2 is fixed by having to meet the constraint of thermal homogeneity of the product on leaving the furnace, this constraint itself being governed by the thermal conduction within the product.
Compared with a given reference situation (given furnace and given hourly production, and therefore given run speed, of given products), the reduction in times Δ 1 and Δ 2 corresponds either to a shortening of the furnace or to an increase in the run speed of the products.
A second aspect of the invention consists in controlling the composition profile of the species of the atmosphere in the furnace and along the entire length of the path traveled by the product through the furnace.
As a matter of fact, the composition of the atmosphere, that is to say especially the contents of the oxidizing components (O 2 , H 2 O, CO 2 ) in the atmosphere, is a parameter which has an impact on the metallurgical quality of the product. Thus, for a given thermal profile, it is possible to optimize the quality of the product by maintaining a higher or lower oxygen content depending on the furnace zone in question.
In FIG. 3 , which shows a reheat furnace, the direction in which the products ( 35 ) run and the flow direction of the smoke are indicated. Curve ( 30 ) is the curve showing the temperature rise of the product.
As the charge ( 35 ) runs through the reheat furnace, it undergoes a first temperature rise in the zone ( 32 ). The temperatures then reach a temperature T decarb . This temperature is typically 700° C. in the case of steels and the sensitivity of the decarburization to this temperature is greater the higher the carbon content of the steel. Above T decarb , and in the presence of oxidizing species, the decarburization and scale formation reaction rates increase: the temperature at which scale formation becomes effective is about 800° C. in the case of steels. The product passes through the zone ( 33 ) and then enters the equalizing zone ( 34 ), when the product is at the temperature T equalization (typically 1100° C.). This zone, at very high temperature, brings the product to its final temperature (T final , typically 1200° C.), and is particularly critical for the formation of scale.
Three ports for installing a diode laser are provided on this furnace. The port ( 36 ) is located in the equalizing zone ( 34 ), the port ( 37 ) is located in the heating zone ( 33 ), the port ( 38 ) is located in the zone ( 32 ) which contains the zone called the recovery zone, whereas the port ( 39 ) is located in the flue ( 31 ).
According to the invention, the concentration of the oxidizing species is measured by the ports ( 36 ), ( 37 ), ( 38 ), ( 39 ), each port receiving a laser beam (via an optical fiber), or a laser beam emitter, a receiver being provided in the opposite wall of the furnace (or else a mirror which sends the beam back parallel to the incident beam, the receiver being placed beside the emitter).
In the zone ( 32 ) (temperature below T decarb ), the fuel and oxidizer flow rates for the burners in the zone ( 32 ) must be adjusted, according to the invention, so as to create an oxygen content in the atmosphere in this zone ( 32 ), measured by the corresponding diode laser, of between 0.5 and 4 vol % and preferably between 2 and 3 vol %.
If the equalizing zone ( 32 ) is not fitted with burners, this correction may be made by the addition of oxidizer via lances, for example oxygen lances, the amount injected being controlled by the measurement of the oxygen content by the diode laser.
The measurement is preferably carried out as close as possible to the product, either via the port ( 38 ) in this zone ( 32 ) or via the port ( 39 ), that is to say in the smoke extraction duct where the same oxygen content is monitored. If the measurement shows a lack of oxygen, this lack must be corrected by regulating the burners, hence increasing the rate of flow of oxidizer (oxygen) to the burners of the zone ( 32 ) or of the preceding zone.
In zone ( 32 ), a protective layer of Fe 2 O 3 and Fe 3 O 4 will be formed and reinforced by the presence of residual oxygen in the smoke. These oxides will be formed to the detriment of more plastic oxides such as FeO or FeSiO 4 which in this case result in strong adhesion of the scale. In addition, at low temperature, the protective conditions (in the parabolic stage of the oxidation) are established more quickly for oxygen partial pressures lying within the aforementioned range (0.5 to 4 vol %).
In the zone ( 33 ) (temperature above T decarb but below T equalization ), the fuel and oxidizer flow rates for the burners in the zone ( 33 ) must be regulated according to the invention so as to produce an oxygen content close to zero in the atmosphere. The atmosphere will be depleted in oxygen, and therefore the fuel, and in particular the CO, will be in excess. Thanks to the measurement carried out via the port ( 37 ), the burners will be regulated in such a way that the O 2 concentration is close to zero and the CO concentration is between 0.1 and 15 vol % and preferably between 1 and 10 vol %. In this higher-temperature zone, it is desired to limit scale formation and decarburization as much as possible, by reducing the concentration of the oxidizing species (O 2 , CO 2 , H 2 O).
In the zone ( 34 ) (temperature above T equalization ) the fuel and oxidizer flow rates for the burners in the zone ( 34 ) must be regulated according to the invention so as to produce an oxygen content in the atmosphere of between 0.5 and 5 vol % and preferably between 1.5 and 4 vol %. The measurement of this concentration is made as close as possible to the product, between 1 mm and 15 cm therefrom, via the port ( 36 ). In this zone and in the presence of oxygen, there is consumption of the decarburized layer by oxidation, which will be accompanied by an increase in porosity of the scale, which will facilitate its removal outside the furnace.
The port ( 39 ) is used to check at all times the CO concentration and the O 2 concentration in the smoke before it is discharged.
When the atmosphere is controlled in this way, according to the invention, the mass of scale is reduced by between 5 and 25%, depending on the nature of the steel.
Likewise, as a general rule it may be noted that the thickness of the decarburized layer is reduced by at least 10%, depending on the contents of the alloying elements and specifically the carbon content.
The gains obtained by controlling the atmosphere are concurrent with the gains made by reducing the times Δ 1 and Δ 2 described above.
FIG. 4 illustrates the monitoring according to the invention of the temperature rise of the product. The invention consists in monitoring the temperature rise of the product and in regulating the burners, by means of a local measurement, zone by zone and a few cm above the charge, of the temperature of the atmosphere in the furnace using a diode laser system.
FIG. 4 shows, in the furnace ( 41 ), the position of the product ( 42 ) and of the thermocouple ( 48 ) according to the prior art. The measurement by the thermocouple ( 48 ) gives a temperature value on the axis of the furnace but far from the product ( 42 ).
According to the invention, one or more diode lasers are fitted in order to measure an average temperature value along the optical path over the width of the furnace. Such an arrangement allows:
an average measurement to be made along the furnace, this being more representative of the product than a discrete measurement in the roof; a measurement close to the product, and therefore directly associated with the surface temperature of the product which is in equilibrium with the temperature of the gas in contact with the said surface; quantification of the relationship between roof temperature and product temperature, which in the prior art was established empirically (by retaining the roof thermocouple).
In FIG. 4 , the number of measurement points has been limited here to three. Preferably, between 1 and 10 measurement points in a furnace will be used.
The furnace ( 41 ) is fitted with ports ( 43 , 44 , 45 ) located above the product ( 42 ).
The furnace operator must comply as closely as possible with the temperature rise profile ( 47 ) of the product. This profile is supplied to the operator, either through his experience, or by means of a chart or via furnace operation software.
To control the product temperature rise ( 47 ), a person skilled in the art hitherto had available only the curve ( 46 ) indicating the roof temperature along the axis of the furnace, the thermocouple ( 48 ) of which delivers, for example, a measurement point as illustrated on the curve. According to the invention, a person skilled in the art now can obtain measurements located along the curve ( 47 ) which are directly associated with the surface temperature of the product. The operator can therefore vary the power of the burners in order to find the desired temperature level on the curve ( 47 ). If the measured temperature is too low, the operator will then increase the heating power in the zone close to the measurement point. Conversely, if the measured temperature is too high, the operator will then reduce the power in the zone close to the measurement point.
The invention also has the following advantage: Certain furnaces use software called “Niveau 2 [Level 2]” to reproduce, whatever the heating conditions, a product temperature rise, according to a given initial profile. Until now, a person skilled in the art did not have available any measurement for continuously confirming the effect of the software. It is another aspect of the invention that this software is coupled with the direct measurements of the product according to the invention, thereby making it possible to systematically verify in real time the intended temperature of the product.
EXAMPLES
Example 1
A first illustrative example is described with the aid of FIG. 5 , which shows the heating curve ( 51 ) associated with a long billet reheat furnace. The combustion is carried out using burners, the fuel for which is natural gas and the oxidizer for which is preheated air, before implementation of the invention. (In this FIG. 5 , the parameters t 1 , . . . and Δ 1 , . . . are in parentheses when they relate to curve 51 according to the prior art and are without parentheses when they refer to curve 52 ).
Implementation of the invention is characterized by replacing the existing burners, the oxidizer for which is air, with burners for which the oxidizer has an oxygen concentration of greater than 21 vol %, and preferably greater than 88 vol %. More preferably, the oxidizer will be industrially pure oxygen. The associated heating curve is the curve ( 52 ). It should be noted that the times Δ 1 and Δ 2 are reduced from 2100 to 1700 seconds and from 5300 to 4800 seconds, respectively. The metallurgical quality of the method obtained according to the curve ( 52 ) will be greatly enhanced by monitoring the heating curve in FIG. 5 , with the installation of diode lasers at the locations explained with regard to FIG. 3 and FIG. 4 or any measurement means allowing this heating profile to be suitably controlled.
FIG. 6 shows the amount of scale produced using the method described above. The amount of scale ( 61 ) is associated with the reference situation and the scale curve ( 62 ) is associated with the implementation of the invention. The two curves have been normalized with respect to the maximum value of the scale thickness obtained under the conditions ( 61 ).
Implementation of the method according to the invention, which reduces Δ 1 by 19% and Δ 2 by 9.5%, makes it possible to reduce the amount of scale by 8% on average (FIG. 6 ). Depending on the experiments, the thickness of the decarburized layer is reduced by between 9 and 17%.
Example 2
The illustrative example below was implemented in a billet reheat furnace having a power of 33 MW and a length of about 30 m. The burners originally present in the furnace were burners called air-fuel burners, the combustion air being preheated to 300° C.
FIG. 7 compares, for an identical heating profile, the amount of scale produced (curve 71 ) with a heating atmosphere whose oxygen concentration in the wet smoke is constant and equal to 3.5 vol %, and the amount of scale produced (curve 72 ) with a heating atmosphere whose oxygen concentration in the wet smoke varies in the following manner:
about 1.5% O 2 (to within 20%) when the skin temperature T is above the equalization temperature T equalization (defined as being between 85% and 90% of the discharge temperature); about 0% O 2 (up to a few hundred ppm) and a CO concentration of between about 0.5 and 3% (to within 20%) for T decarb <T<T equalization , T decarb being the decarburization start temperature (700° C.); and about 2% O 2 (to within 20%) when the skin temperature T is below T decarb .
The mean O 2 concentration in the smoke may be measured by a standard oxygen probe, but it may be preferable to employ a diode laser (of the “TDL” type), the beam of which passes at a distance of less than about 6 cm from the treated product, for fine monitoring, in real time, of a variation in concentration of the species above at the surface of the product so as to better meet the atmosphere profile set in order to match the heating profile.
According to this Example 2, implementation according to the invention allows the thickness of the scale to be reduced by 11% (FIG. 7 ). Depending on the experiments, the thickness of the decarburized layer is reduced by between 12 and 20%.
It will be understood that many additional changes in the details, materials, steps and arrangement of parts, which have been herein described in order to explain the nature of the invention, may be made by those skilled in the art within the principle and scope of the invention as expressed in the appended claims. Thus, the present invention is not intended to be limited to the specific embodiments in the examples given above and/or in the figures. | The method and apparatus for enhancing the metallurgical quality of products treated in a furnace with several zones, wherein the temperature and the atmospheric conditions can be controlled. The applies to any type of product treated in a furnace, such as billets, blooms, slugs or slabs. Alternatively, this may be used by iron and steel manufacturers in the production line for sheets, plates, tubes, etc. | 2 |
FIELD
This invention relates to the field of integrated circuit fabrication. More particularly, this invention relates to thinning the layers that are formed during the fabrication of integrated circuits.
BACKGROUND
As integrated circuits have become increasingly smaller, electrically conductive structures within the integrated circuits are placed increasingly closer together. This situation tends to enhance the inherent problem of parasitic capacitance between adjacent electrically conductive structures. Thus, new electrically insulating materials have been devised for use between electrically conductive structures, to reduce such capacitance problems. The new electrically insulating materials typically have lower dielectric constants, and thus are generally referred to as low k materials. While low k materials help to resolve the capacitance problems described above, they unfortunately tend to introduce new challenges.
Low k materials are typically filled with small voids that help reduce the material's effective dielectric constant. Thus, there is less of the material itself within a given volume, which tends to reduce the structural strength of the material. The resulting porous and brittle nature of such low k materials presents new challenges in both the fabrication and packaging processes. Unless special precautions are taken, the robustness and reliability of an integrated circuit that is fabricated with low k materials may be reduced from that of an integrated circuit that is fabricated with traditional materials, because low k materials differ from traditional materials in properties such as thermal coefficient of expansion, moisture absorption, adhesion to adjacent layers, mechanical strength, and thermal conductivity.
Low k materials are typically more brittle and have a lower breaking point than other materials. One reason for this is the porosity of the low k material, where a significant percentage of its physical volume is filled with voids. Thus, integrated circuits containing low k materials are inherently more prone to breaking or cracking during processes where physical contact is made with the integrated circuit surface, such as wire bonding and electrical probing, or processes that cause bending stresses such as mold curing, underfill curing, solder ball reflow, chemical mechanical polishing, or temperature cycling.
As integrated circuits have become smaller, they have shrunk not only in the amount of surface area required by the circuit, but also in the thicknesses of the various layers by which they are formed. As the thicknesses of the layers has decreased, it has become increasingly important to planarize a given layer prior to forming a subsequent overlying layer. One of the methods used for such planarization is called chemical mechanical polishing. During chemical mechanical polishing, the surface of the layer to be planarized, thinned, or both is brought into contact with the surface of a polishing pad. The pad and the substrate are rotated and translated relative to each other in the presence of a polishing fluid, which typically contains both physical erosion particles and chemical erosion compounds.
Unfortunately, the need to planarize the layers of an integrated circuit using traditional chemical mechanical polishing has become a problem, because the amount of down force and friction required to adequately erode a layer using chemical mechanical polishing has become great enough to crush, shear, or otherwise damage the increasingly delicate underlying low k layers as they are reduced in thickness with the general reduction in the size of integrated circuits.
For example, in copper dual damascene processing, there is a step to remove unwanted portions of a deposited copper layer from an upper surface of an integrated circuit. New integrated circuit designs place delicate low k layers somewhere beneath the copper layer to be removed. Traditional chemical mechanical polishing processes tend to be too rough during the removal of the copper layer, and damage the low k layer. Electropolishing is a more gentle method than chemical mechanical polishing, and has also been used to remove electrically conductive layers, such as copper. However, electropolishing tends to be unable to break through the oxidation on the surface of the copper layer, and thus is also inadequate for removing the copper layer. In addition, electropolishing also tends to not be able to remove the barrier layer and seed layer that often underlie the copper layer.
There is a need, therefore, for a new system for use in integrated circuit fabrication, which helps to alleviate one or more of the challenges mentioned above, and enables layers within an integrated circuit to be planarized or otherwise removed without damaging delicate underlying layers.
SUMMARY
The above and other needs are met by a system for thinning a layer on a substrate without damaging a delicate underlying layer in the substrate. The system includes means for mechanically eroding the layer on the substrate, and means for electropolishing the layer on the substrate.
In This manner, portions of the layer that cannot be removed by electropolishing can be removed by the mechanical erosion. However, electropolishing can preferentially be used on some portions of the layer so that unnecessary mechanical stresses can be avoided. Thus, the system imparts less mechanical stress to the substrate during the removal of the layer, and the delicate underlying layer receives less damage during the process, and preferably no damage whatsoever.
In various embodiments, the means for mechanically eroding the layer and the means for electropolishing the layer are configured to operate simultaneously. Preferably, the means for mechanically eroding the layer includes any one or combination of a rotating polishing pad, a rotating brush, and a spray nozzle adapted to direct a spray of a solution towards the layer. The means for electropolishing the layer preferably includes means for establishing a voltage potential through an electrically conductive liquid between the layer on the substrate and the means for mechanically eroding the layer.
According to another aspect of the invention there is described a system for thinning a layer on a substrate without damaging a delicate underlying layer in the substrate. An electropolishing pad mechanically erodes the layer on the substrate. A power supply establishes a voltage potential through a bath of an electrically conductive liquid between the layer on the substrate and the electropolishing pad.
In various embodiments of this aspect of the invention, the voltage potential has a range of between about one tenth of one volt and about one hundred volts. In some embodiments the system also includes a brush for mechanically eroding the layer on the substrate, and a spray nozzle adapted to direct a spray of the electrically conductive liquid towards the layer.
According to another aspect of the invention there is described a method for thinning a layer on a substrate without damaging a delicate underlying layer in the substrate, where a first portion of the layer is mechanically eroded, and a second portion of the layer is electropolished.
In various embodiments of this aspect of the invention, the first portion of the layer is one or both of an overlying oxidized portion of the layer and an underlying portion of the layer that is formed of a material that cannot be removed by electropolishing. The second portion of the layer preferably includes a metal, and is most preferably copper. In one embodiment, the first portion of the layer is electropolished simultaneously with the mechanical erosion, and in another embodiment the second portion of the layer is mechanically eroded simultaneously with the electropolishing. Preferably, the layer includes a first electrically conductive layer, an underlying non electrically conductive barrier layer, and an intervening electrically conductive seed layer. The delicate underlying layer is preferably formed of a low k material. In one embodiment, the first portion of the layer is thinned to a relatively greater extent by mechanical erosion and is thinned to a relatively lesser extent by electropolishing, and the second portion of the layer is thinned to a relatively greater extent by electropolishing and is thinned to a relatively lesser extent by mechanical erosion.
BRIEF DESCRIPTION OF THE DRAWINGS
Further advantages of the invention are apparent by reference to the detailed description when considered in conjunction with the figures, which are not to scale so as to more clearly show the details, wherein like reference numbers indicate like elements throughout the several views, and wherein:
FIG. 1 is a functional block diagram of a chemical mechanical electropolishing system according to a preferred embodiment of the present invention.
FIG. 2 is a cross sectional view of a portion of an integrated circuit on a substrate, depicting the layers to be removed, and the delicate underlying layer.
FIG. 3 is a cross sectional view of a portion of an integrated circuit on a substrate, depicting the delicate underlying layer and the structure that is formed after the layers have been removed.
FIG. 4 is a flow chart of a first embodiment of a method of processing a substrate with a system according to the present invention.
FIG. 5 is a flow chart of a second embodiment of a method of processing a substrate with a system according to the present invention.
DETAILED DESCRIPTION
With reference now to FIG. 1 , there is depicted a functional block diagram of a chemical mechanical electropolishing system 10 according to a preferred embodiment of the invention. The system 10 differs in many important aspects from either a traditional chemical mechanical polishing system or an electropolishing system, which differing aspects enable the chemical mechanical electropolishing, or CME, system 10 to thin or remove layers, such as a copper layer, without damaging delicate underlying layers, such as low k layers. The system 10 is also capable of removing additional layers, such as barrier layers and seed layers, which often underlie the main layer to be remove.
The system 10 is used for processing a substrate 12 on which integrated circuits are formed. The substrate 12 is preferably formed of a semiconducting material, such as of group IV materials like silicon, germanium, or silicon germanium, or group III-V materials such as gallium arsenide. However, in other embodiments the substrate 12 is an insulating substrate, such as alumina, sapphire, or glass. FIG. 2 is a cross sectional view of a portion of an integrated circuit including the substrate 12 . A structure 44 has been formed in a layer 36 of the substrate 12 , which layer 36 may be a low k layer, or a layer of another material which is delicate and easily damaged, as generally described above.
The layer 36 , in the example depicted in FIG. 2 , is overlaid with a barrier layer 38 , a seed layer 40 , and a conductive layer 42 , such as a copper layer. As can be seen, the barrier layer 38 and the seed layer 40 line the surfaces of the structure 44 , and the conductive layer 42 fills the structure 44 . However, it is desired to remove the layers 38 , 40 , and 42 from the upper surfaces of the layer 36 , to produce the structure 44 as depicted in FIG. 3 . It is this process of removing those upper portions of the layers 38 , 40 , and 42 where prior processing methods have proven to be inadequate, either by not completely removing the layers, or by damaging the delicate layer 36 in the process of such removal. The system 10 as depicted in FIG. 1 is adapted to remove the layers 38 , 40 , and 42 , while reducing and preferably eliminating these problems. FIGS. 2 and 3 depict a single damascene structure. However, it is appreciated that the embodiments of the invention as described herein are equally applicable to dual damascene and other structures.
The substrate 12 is preferably retained by a carrier 16 , which most preferably provides a rigid support across the entire back surface of the substrate 12 . Thus, the front surface of the substrate 12 , or in other words the surface of the substrate 12 on which the layers 38 , 40 , and 42 are formed as depicted in FIG. 2 , is presented for processing by the system 10 . A method for making an electrical contact with the front surface of the substrate 12 is established but not shown. This contact is necessary for the electropolishing process to occur. The front surface of the substrate 12 is preferably applied against an electropolishing pad 14 during at least a portion of the processing. The electropolishing pad 14 is preferably different in many respects from a standard polishing pad that is used in tradition chemical mechanical polishing.
For example, the electropolishing pad 14 is preferably formed of a material that is similar to a standard polishing pad, with a conductive filler added. By reducing down force, less friction is developed between the electropolishing pad 14 and the substrate 12 . By reducing the friction between the electropolishing pad 14 and the substrate 12 in this manner, there is less shearing force developed in the delicate layer 36 , which tends to reduce the amount of damage sustained by the layer 36 during processing.
Most preferably, the substrate 12 is applied against the electropolishing pad 14 with a force that is reduced from that which is traditionally used for chemical mechanical polishing. By reducing the down force applied between the substrate 12 and the electropolishing pad 14 , two benefits are realized. First, the friction is reduced between the substrate 12 and the electropolishing pad 14 , which reduces the shearing force in the layer 36 , and thereby reduces the amount of damage to the layer 36 , as described above. Second, the crushing force applied to the layer 36 is also reduced, which further reduces the amount of damage sustained by the layer 36 during the process. In addition, reducing the amount of down force used during processing of the substrate 12 tends to reduce the amount of dishing and erosion that occurs within the structure 44 .
In a standard chemical mechanical polishing process, the amount of down force applied between the polishing pad and the substrate is between about four pounds per square inch and about nine pounds per square inch. In the preferred embodiments of the present invention, the down force between the electropolishing pad 14 and the substrate 12 is reduced to be less than about four pounds per square inch, and in a most preferred embodiment is about one and one half pounds per square inch.
In addition, the electropolishing pad 14 is preferably electrically conductive. In this manner, an electrical potential can be applied through the electropolishing pad 14 , such as by using the electropolishing pad 14 as an electrode, in a manner that is described in more detail hereafter. Further, in one embodiment of the invention, the electropolishing pad 14 is fabricated to have a presented surface area that is smaller than the surface area of the substrate 12 that is presented for processing. One example of this is an electropolishing pad 14 that is circular, and which has a smaller diameter than the generally circular substrate 12 with which it is used. In some embodiments the processing surface area of the electropolishing pad 14 is between about twenty percent and about fifty percent of the processing surface area of the substrate 12 . However, a standard size electropolishing pad 14 could also be used. A typical chemical mechanical polishing pad has a processing surface area that ranges from about twenty-five percent larger than the processed surface area of the substrate 12 , to about fifteen times the surface area of the substrate 12 . Thus, a typical chemical mechanical polishing pad is usually much larger than the surface of the substrate 12 that it is used to process.
However, by reducing the surface area of the electropolishing pad 14 to be less than the surface area of the substrate 12 which it is used to process, the total amount of friction generated between the electropolishing pad 14 and the substrate 12 is reduced. As described above, this further reduction in the amount of friction generated between the electropolishing pad 14 and the substrate 12 tends to reduce the amount of shearing force that is generated within the layer 36 , and thus tends to reduce the amount of damage that is sustained by the layer 36 during processing in the system 10 .
The electropolishing pad 14 is preferably mechanically connected to a motion controller 24 , such as by a spindle 22 or other means. In this manner the motion controller 24 enables the electropolishing pad 14 to be moved in a variety of ways. For example, the electropolishing pad 14 can be oscillated, such as in an X or Y direction, or a combination of the two, or along other nonrectilinear axes. Further, the electropolishing pad 14 can be rotated, such as around the spindle 22 . In addition, the entire electropolishing pad 14 can be moved in an orbital motion, such as by translating the spindle 22 around the circumference of a circle, or along an irregular path, or along paths that change according to either a regular or a pseudorandom pattern. The electropolishing pad 14 can also be caused to vibrate, such as with an ultrasonic motion or other high speed motion. In this manner, the electropolishing pad 14 is preferably moved across the surface of the substrate 12 in an even manner, so that the removal of the layers 38 , 40 , and 42 is accomplished uniformly across the surface of the substrate 12 .
The substrate 12 is also preferably moved relative to the electropolishing pad 14 , such as by engagement with a spindle 18 between the carrier 16 and a motion controller 20 . The substrate 12 can preferably be moved in all of the same ways as those described above in regard to the electropolishing pad 14 . For example, the substrate 12 can preferably be oscillated, such as in an X or Y direction, or a combination of the two, or along other nonrectilinear axes. Further, the substrate 12 can be rotated, such as around the spindle 18 . In addition, the entire substrate 12 can be moved in an orbital motion, such as by translating the spindle 18 around the circumference of a circle, or along an irregular path, or along paths that change according to either a regular or a pseudorandom pattern. The substrate 12 can also be caused to vibrate, such as with an ultrasonic motion or other high speed motion.
Most preferably there is some amount of relative motion that is produced by the substrate 12 's motion controller 20 , and some amount of relative motion that is produced by the electropolishing pad 14 's motion controller 24 . However, it is appreciated that in various embodiments it is possible to produce the relative motion using only one of the motion controller 20 and the motion controller 24 , in which case the other motion controller could be omitted from the system 10 design. In a most preferred embodiment, a different motion set is produced by each of the motion controllers 20 and 24 . For example, the motion controller 20 could cause the substrate 12 to rotate around the axis of the spindle 18 or other connection means, while the motional controller 24 causes the electropolishing pad 14 to rotate about the spindle 22 and orbit across the entire surface area of the substrate 12 . Other such combinations of relative motion are also comprehended herein.
In a most preferred embodiment, at least one component of the relative motion between the substrate 12 and electropolishing pad 14 is at a speed that is dramatically greater from that which is traditionally used for chemical mechanical polishing. One purpose for this is to increase the rate at which material is removed from the surface of the substrate 12 . Without being bound by theory, the rate of material removal is generally proportional to the force exerted or the friction generated between the substrate 12 and electropolishing pad 14 , and the relative speed of motion between the surfaces of the substrate 12 and the electropolishing pad 14 . As the force and friction between the substrate 12 and the electropolishing pad 14 are generally reduced when processed on the system 10 as described herein, the rate of material removal is preferably enhanced or otherwise compensated for by increasing the speed of relative motion. Most preferably, the electropolishing pad 14 is rotated at a speed of between about one hundred rotations per minute and about six hundred rotations per minute. Smaller diameter electropolishing pads 14 are most preferably rotated at the higher speed and larger diameter electropolishing pads 14 are most preferably rotated at the lower speed.
The substrate 12 and the electropolishing pad 14 are preferably brought into contact in the presence of an abrasive electrolyte 26 that is held by the system 10 , such as within a bath 28 . In other embodiments the abrasive electrolyte 26 may also be introduced by a spray or stream, as described in more detail hereafter. The abrasive electrolyte 26 is different from a standard chemical mechanical polishing solution or rouge in a variety of important respects. For example, the abrasive electrolyte 26 is designed to be both electrically conductive and mechanically abrasive. The abrasive electrolyte 26 may also be chemically abrasive to some degree.
Although some chemical mechanical polishing solutions may be water based, or based on some other electrically conductive fluid, the abrasive electrolyte 26 is different from these solutions, in that it does not contain impurities which prohibit or otherwise inhibit or degrade an electrolytic oxidation or other removal of the electrically conductive layer 42 , which is most preferably copper. Typical polishing solutions are filled with materials that would tend to plate out or otherwise degrade such a reaction. However, the abrasive electrolyte 26 is preferably free of such materials, and other materials which would tend to oxidize, reduce, or otherwise react at the voltage potentials desired for the oxidation reaction that can be used to help remove the conductive layer 42 .
Further, the abrasive electrolyte 26 preferably includes abrasive particles. The abrasive particles are preferably inert to the other reactions, both electrical and chemical, which may be occurring within the bath 28 . Most preferably, the abrasive particles have a size of between about fifty nanometers and about two hundred and fifty nanometers in average diameter. Thus, the abrasive particles within the abrasive electrolyte 26 are preferably similar to the abrasive particles found within a slurry used for chemical mechanical polishing.
Further, in a preferred embodiment, both the substrate 12 and the electropolishing pad 14 are entirely contained within the bath 28 of the abrasive electrolyte 26 . In this manner an electrical potential can preferably be established between the substrate 12 , such as by way of the carrier 16 , and the electropolishing pad 14 , such as by way of the spindle 22 or other backing element. Thus, the substrate 12 and the electropolishing pad 14 are preferably used as electrodes during at least a portion of the processing of the substrate 12 , and the abrasive electrolyte 26 acts as the current carrying medium between the electrode substrate 26 and the electrode electropolishing pad 14 .
It is appreciated that the electrical potential applied between the substrate 12 and the electropolishing pad 14 can be sustained without there being a complete bath 28 of the abrasive electrolyte 26 . Thus, in other embodiments there is some amount of the abrasive electrolyte 26 introduced between the substrate 12 and the electropolishing pad 14 , but not an amount sufficient to immerse both the substrate 12 and the electropolishing pad 14 . However, in the most preferred embodiment the substrate 12 and the electropolishing pad 14 are both substantially immersed in the abrasive electrolyte 26 during at least a portion of the processing, such as when an electrical potential is applied between the two.
The entire operation of the system 10 is preferably controlled by a controller 30 , which may be remotely located, but is preferably local to the rest of the system 10 . The controller 30 preferably controls parameters such as, but not limited to, the pressure or down force between the substrate 12 and either the brush 46 or the electropolishing pad 14 , the pressure of the spray 48 , the speed and type of the relative motion between the substrate 12 and any one of the electropolishing pad 14 , the brush 46 , and the spray 48 , the electrical potential between the substrate 12 and either the electropolishing pad 14 or the brush 46 , and which of the electropolishing pad 14 , brush 46 , and spray 48 to use at any given time, if any, and for how long.
Input such as for the programming of the system 10 is preferably received through an input 32 , which may include such devices as a keyboard, a pointing device such as a mouse or joystick, and a network interface such as can be used for receiving programming and other instructions across a computer network. Most preferably the system 10 also includes a display 34 of some type, upon which information in regard to the programming, processing, and progress of the system 10 can be presented.
There are many modes in which the system 10 can operate, which modes preferably depend at least in part upon the materials, thicknesses, and other properties of the layers such as 38 , 40 , and 42 that are to be removed from the surface of the substrate 12 , and the nature of the underlying delicate layers, such as 36 . Thus, any specific embodiments described herein are not intended to be limitations on all possible embodiments of the system 10 or its use.
For example, in the case where the conductive layer 42 is a copper layer, and the underlying layer 36 is a delicate low k layer, there are many challenges to be overcome, as described above. The system 10 overcomes these challenges by way of its unique capabilities. For example, to remove the oxide that tends to form on the surface of the copper layer 42 , and which tends to inhibit the use of electropolishing, the electropolishing pad 14 can be brought into contact with the surface of the substrate 12 for a period of time and with a down force that is just sufficient to remove the oxidation. At that point in time, the down force between the substrate 12 and the electropolishing pad 14 can be reduced, or the contact between the substrate 12 and the electropolishing pad 14 can be removed altogether.
Then a potential can be applied between the substrate 12 and the electropolishing pad 14 , so that the copper conductive layer 42 is removed by an oxidation or other reaction, such as etching by an acidic abrasive electrolyte. When the copper conductive layer 42 is substantially removed, the electropolishing pad 14 can again be brought in to contact with the substrate 12 , or the down force between the electropolishing pad 14 and the substrate 12 can be increased. In this manner, any remaining portions of the seed layer 40 , and the barrier layer 38 , which is typically formed of a nonconductive material, can be removed, yielding the structure 44 as depicted in FIG. 3 .
It is appreciated that there are many permutations and combinations of steps such as those described in the specific example above, which can be used to planarize or otherwise remove various layers from the surface of the substrate 12 while reducing or eliminating the damage to the delicate underlying layers, such as layer 36 . The system 10 tends to reduce such damage by reducing the amount of down force that is required for processing, and reducing the friction between the substrate 12 and the electropolishing pad 14 . Further, the system 10 makes use of electrochemical processing to erode the electrically conductive layers, thus further reducing or eliminating the need for contact between the substrate 12 and the electropolishing pad 14 , which further preserves the integrity of the delicate layers such as layer 36 .
In alternate embodiments of the system 10 , a brush 46 is used either in addition to or in place of the electropolishing pad 14 . For example, the brush 46 may replace the electropolishing pad 14 . Alternately, either the electropolishing pad 14 can be moved away from the substrate 12 to allow room for the brush 46 to be used, or the substrate 12 can be moved away from the electropolishing pad 14 to be adjacent the brush 46 . The brush 46 may be able to better remove specific layers, or better remove layers from different structures of the integrated circuit than the electropolishing pad 14 . For example, a brush 46 , because of its generally reduced amount of surface contact, relative to the electropolishing pad 14 , will tend to induce lesser forces within the substrate 12 . The brush 46 may be one or more of a rolling brush or a rotating brush, or may have some other type of relative motion, produced by a motion controller 50 for example, such as is described above in regard to the motion of the substrate 12 and the electropolishing pad 14 .
Similarly, a spray 48 may also be used, either in some combination with the electropolishing pad 14 and the brush 46 , or as a replace for one or both of the electropolishing pad 14 and the brush 46 . For example, the electropolishing pad 14 or the brush 46 can be moved away from the substrate 12 to allow room for the spray 48 to be used, or the substrate 12 can be moved away from the electropolishing pad 14 or the brush 46 to be adjacent the spray 48 . The spray 48 preferably sprays the abrasive electrolyte 26 against the surface of the substrate 12 . In preferred embodiments, the level of the bath 28 is reduced when the spray 48 is used, so that the bath 28 of the abrasive electrolyte 26 does not impede the force of the spray 48 .
The spray 48 may also take one or more of a variety of different forms. For example, the spray 48 may be pulsated, such as with an ultrasonic or other frequency. Further, the spray 48 may be oscillated, spun, or otherwise moved relative to the surface of the substrate 12 , such as with one or more of the motions described above in regard to the substrate 12 and the electropolishing pad 14 . In addition, the spray 48 may be a single jet or multiple jets, and may in different embodiments be directed from a single angle toward the substrate 12 , an adjustable or varying angle, or from a variety of simultaneous angles. The spray 48 may also have some other type of relative motion, produced by a motion controller 52 for example, such as is described above.
In some embodiments, the use of the spray 48 or the brush 46 may be preferred over the use of the electropolishing pad 14 at different points during the processing of the substrate 12 . For example, the spray 48 or brush 46 could be used during removal of a surface oxidation from the conductive layer 42 , or during the removal of one or both of the seed layer 40 and the barrier layer 38 , or even to increase the rate of material removal during the electropolishing of the conductive layer 42 , in a manner that is more gentle than the application of the electropolishing pad 14 .
In other embodiments, all three of the electropolishing pad 14 , the brush 46 , and the spray 48 are used during the processing of the substrate 12 . For example, the spray 48 may be used simultaneously with either the electropolishing pad 14 or the brush 46 . Alternately, the electropolishing pad 14 , the brush 46 , and the spray 48 can be separately used at different points in the processing of the substrate 12 , such as when the particular attributes of a given one of the electropolishing pad 14 , the brush 46 , and the spray 48 are most suitable for removal of a given portion of the layers 38 , 40 , and 42 , such as removing an oxide from the surface, removing the conductive layer 42 , removing one or both of the seed layer 40 and the barrier layer 38 , or cleaning off the surface of the layer 36 to ensure than no remaining traces of the removed materials are left behind. In this embodiment, all three of the electropolishing pad 14 , the brush 46 , and the spray 48 are present in the system 10 .
FIGS. 4 and 5 depict flow charts for two additional possible processing flows 60 and 80 , which are presented by way of example. In FIG. 4 , process 60 starts when a substrate 12 is presented for processing on the system 10 , as given in block 62 . The substrate 12 is initially processed with the electropolishing pad 14 and with the potential applied, as given in block 64 . The substrate 12 may be inspected periodically, as given in block 66 , to determine whether the desired amount of processing has been performed. If not, then processing of the substrate 12 is continued as given in block 64 . If so, then processing of the substrate 12 is completed by one or more of the other methods, such as given in block 68 . The completed substrate 12 is delivered for further processing, as given in block 70 , when all of the processing on system 10 has been completed.
Similarly, in FIG. 5 , process 80 starts when a substrate 12 is presented for processing on the system 10 , as given in block 82 . The substrate 12 is initially processed with the electrolytic reaction between the substrate 12 and some other electrode, such as either the brush 46 or the electropolishing pad 14 , as given in block 84 , in which the abrasive electrolyte 26 is used as the conducting medium. The substrate 12 may be inspected periodically, as given in block 86 , to determine whether the desired amount of processing has been performed. If not, then processing of the substrate 12 is continued as given in block 84 . If so, then processing of the substrate 12 is completed by one or more of the other methods, such as given in block 88 . The completed substrate 12 is delivered for further processing, as given in block 90 , when all of the processing on system 10 has been completed.
The foregoing description of preferred embodiments for this invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiments are chosen and described in an effort to provide the best illustrations of the principles of the invention and its practical application, and to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled. | A system for thinning a layer on a substrate without damaging a delicate underlying layer in the substrate. The system includes means for mechanically eroding the layer on the substrate, and means for electropolishing the layer on the substrate. In this manner, portions of the layer that cannot be removed by electropolishing can be removed by the mechanical erosion. However, electropolishing can preferentially be used on some portions of the layer so that unnecessary mechanical stresses can be avoided. Thus, the system imparts less mechanical stress to the substrate during the removal of the layer, and the delicate underlying layer receives less damage during the process, and preferably no damage whatsoever. | 8 |
RELATED APPLICATIONS
The current application claims priority to the U.S. Provisional Application Ser. No. 61/937,512 filed Feb. 8, 2014.
BACKGROUND
Technological advancements have made personal ownership of a storm shelter more affordable, and hence more available, to the homeowner. The market for storm shelters has grown significantly; underground storm shelters and safe rooms are much more prevalent in new home construction in recent years. There is a market demand for a concealed underground shelter, be it for safe retreat from a storm and/or for the concealed underground storage of valuables such as guns and ammunitions, other valuables, and survival rations such as food, water, medicines and the like. This demand comes from a steady and recent rise in global societal/political turmoil, unrest, threat of war, coupled with the economic instability of major countries around the world. A result is a group of citizens generally referred to as “preppers,” named for the fact that they are preparing for economic and social unrest of varying predicted degrees. This market demand is satisfied by an underground shelter that, when closed, is advantageously concealed to the view of others above ground. It is to these improvements that the embodiments of the present invention are directed.
SUMMARY
Some embodiments of this technology contemplate an underground shelter having an open-top enclosure and a base. A linkage assembly selectively moves the base between an opened position and a closed position. A lifting mechanism lifts the base in opposition to a force of gravity on the base in the opened position. A concealment object is supported upon the base to conceal the existence of the underground shelter below.
BRIEF DESCRIPTION OF THE DRAWINGS
Details of various embodiments of the present invention are described in connection with the accompanying drawings that bear similar reference numerals.
FIG. 1 diagrammatically depicts a side view of an underground shelter in the opened position that is constructed in accordance with embodiments of the present invention.
FIG. 2 is an enlarged detail of a portion of the shelter of FIG. 1 .
FIG. 3 depicts the shelter of FIG. 1 but in the closed position.
FIG. 4 depicts a partial cross sectional top view of the links nesting in the closed position.
FIG. 5 is an isometric depiction of the concealment object being a fire pit.
FIG. 6 is an isometric depiction of the concealment object being a condensing unit.
FIG. 7 is an isometric depiction of the concealment object being a dog house.
FIG. 8 depicts modular forms for constructing an underground open-top concrete enclosure that is sized to support the shroud as depicted in FIG. 1 .
FIG. 9 depicts a top view of the concrete forms in FIG. 5 joined together for pouring the underground open-top concrete enclosure.
DESCRIPTION
The presently disclosed technology contemplates an underground shelter having an enclosure with an open top. The shelter also has a lid that is selectively moved to a closed position to close the enclosure. The lid includes an above-ground object not normally associated with an underground shelter, in order to conceal the existence of the underground shelter when the lid is closed.
For purposes of this disclosure certain embodiments are described in which the enclosure is constructed of concrete, and preferably of a monolithic concrete pour made possible by the use of a modular form system. That modular form system is included in the disclosure of Applicant's previously filed provisional application Ser. No. 61/892,201 filed on Oct. 17, 2013 which is assigned to the assignee of this application and which is incorporated herein in its entirety.
FIG. 1 diagrammatically depicts a side view of a shelter 100 that is constructed in accordance with illustrative embodiments of the present invention. The shelter 100 depicted in FIG. 1 is in the opened position, such that a user can enter or leave the shelter via an exposed entry 109 . To construct the enclosure 102 , first an oversize trench is excavated and then concrete forms are placed inside the trench. Concrete can then be poured against the forms. When the concrete is sufficiently cured the forms can be removed, as explained below in more detail, exposing the cured concrete in its formed shape of an open-top enclosure 102 .
In these illustrative embodiments the top edge 104 of the open top enclosure 102 is formed below grade 106 . A shroud 108 is attached to a portion of the top edge 104 , such as by the plurality of fasteners 110 embedded in the concrete. The shroud 108 generally forms an accessible entry 109 through which users can readily pass to enter or leave the shelter 100 . The shroud 108 can be constructed of structural components that are formed and/or welded metal components, composite material components, and the like. The height of the shroud 108 can be related to the number of steps that are traversed to reach the top edge 104 of the enclosure 102 . Typically, a stair rise of about 9.5 inches is specified for an ergonomically effective stairway. Here, there are two steps 112 , 114 supported by the shroud 108 and used to stand partially within the entry 109 . Thus, in these depicted embodiments the shroud 108 is about nineteen inches high. Additional steps 116 , 118 supported by the enclosure 102 are used to stand partially within the enclosure 102 when either entering or leaving the shelter 100 .
FIG. 2 is an enlarged detail of a portion of FIG. 1 . The entry 109 in these illustrative embodiments is rectangular, having a longitudinal length depicted by “L entry .” That L entry corresponds to the size of a base 120 having a longitudinal length “L base ” such that in the closed position ( FIG. 3 ) the base 120 sealingly engages against the shroud 108 to close the entry 109 . A seal can be attached to either the base 120 or the shroud 108 , or both. The base 120 is latched in a closed position that compressingly engages the seal to seal the enclosure 102 from exterior moisture, debris, and animal invaders.
Returning to FIG. 1 , each side of the base 120 is supported by two links 122 , 124 that are connected to the shroud 108 at respective lower ends by pins 126 , 128 , and that are connected to the base 120 at respective upper ends by pins 130 , 132 . A lifting mechanism 133 exerts a lifting force to lift the base 120 , and whatever is supported by the base as discussed below, against the force of gravity. In the depicted embodiments the lifting mechanism 133 is a gas shock, although the contemplated embodiments are not so limited. In alternative equivalent embodiments a spring and the like can provide the lifting force.
Importantly, the parallel links 122 , 124 keep the platform 120 substantially level at all times when moving between the opened and closed positions. That permits placing a concealment object 138 on the platform 120 that has items that could be spilled or toppled if not maintained in a level orientation. The fire pit 138 1 discussed below, for example, could spill hot embers or lava rocks if it was not held level at all times. In alternative embodiments where holding the object 138 level is not essential, then other configurations for the links can be used.
A lever 134 is presented to the user to grasp and rotate clockwise (push/pull downward) to rotate the link 122 , and in turn the base 120 , in a clockwise direction. The other link 124 passively rotates likewise in the clockwise direction. When the links 122 , 124 rotate past the vertical position, the force of gravity assists the base 120 (and whatever it supports) in lowering until it ultimately can be latched in the closed position, sealingly engaging against the top end of the shroud 108 . The gas shock 133 in these illustrative embodiments advantageously provides resistance against the downward movement to prevent the base 120 from slamming shut on the shroud 108 . FIG. 3 is a view similar to FIG. 1 but depicting after the base 120 has been latched in the closed position. In the closed position the base 120 has a catch (not depicted) that engages a latch 135 to resist the opening force of the lifting mechanism 133 . Preferably, the latch 135 is electronically actuated wirelessly so that a user can remotely actuate the latch 135 while walking toward the shelter. In the event of a transmitter failure a manual override can be provided to acutate the latch 135 if the operator has the appropriate credentials, such as by holding a key fob, to grant the operator access to actuating the latch 135 .
FIG. 4 is a cross sectional view depicting how the links 122 , 124 can be staggered laterally so that they can overlap longitudinally in the closed position. The pin 126 is supported in free rotation within a bearing 136 in the shroud 108 . The lower end of the link 122 and the lever 134 are both rigidly affixed in rotation with the pin 126 . The pins 128 , 130 , 132 are likewise coupled by respective bearings 136 permitting free rotation, and the lower end of the link 124 is likewise affixed in rotation with the pin 128 .
In these illustrative embodiments the pin 126 can extend to span both opposing sides of the shroud 108 forming the entry 109 . This permits attaching the single lever 134 as depicted, midway between the links 122 , so that a force applied to the lever 134 is equally distributed to each of the links 122 . In equivalent alternative embodiments (not depicted) two levers 134 can be provided, each attached closely to the respective link 122 .
Returning to FIG. 1 , the base 120 supports an above-ground object 138 that is intended to conceal the presence of the underground shelter 100 below. That is, generally, an above ground view of the object 138 in the closed position of the shelter 100 ( FIG. 3 ) would intentionally mislead the unknowing viewer into believing that an underground shelter 100 cannot exist beneath the object 138 . For example, without limitation, FIG. 5 depicts embodiments that contemplate the object 138 being a gas fire pit 138 1 . The fire pit 138 1 is attached to the top side of the base 120 , such as with fasteners passing through apertures 139 in the base 120 . The lifting mechanism 133 ( FIG. 1 ) is specified according to what lifting force is necessary to lift the combined weight of the fire pit 138 1 and the base 120 . The gas can be supplied via a flexible gas line to accommodate the displacement of the fire pit 138 1 when moved to the opened position. Alternatively, the gas can be supplied by a self-contained container of gas that moves with the fire pit 138 1 .
FIG. 6 depicts alternative embodiments that contemplate the object 138 being an outdoor condensing unit 138 2 in an air conditioning system. The condensing unit can be an actual functioning unit or it can be a decoy unit. In either event the power and tubing connections are made with adequate flexible loops to permit the condensing unit 138 2 to move to the opened position. FIG. 7 depicts yet other alternative embodiments that contemplate the object 138 being an outdoor dog house 138 3 . The skilled artisan readily ascertains from these illustrative embodiments that the object 138 , either real or decoy, is something the viewer would be accustomed to seeing in its environment but effectively concealing the fact that it is attached to the lid of the underground storage shelter 100 . An enumeration of all types of such outdoor objects that can be used to perform that function is not necessary for the skilled artisan to understand the contemplated scope of the present technology.
With further reference to the concrete enclosure 102 described in brief above, FIG. 8 depicts a modular concrete form system that is well suited for use in this technology. An end panel assembly 148 is constructed by joining two panels 150 , 152 together edge-to-edge. Flanges 154 , 156 at the mating edges of the panels 150 , 152 provide protuberant surfaces that are well adapted for connecting together with a clamping mechanism 158 , such as a c-clamp or a vise-grip and the like. A flange 160 extends substantially orthogonal to the panel 152 , and another flange 162 extends substantially orthogonal to the flange 160 . Although not depicted, the panel 150 likewise has two orthogonal flanges extending inwardly and downwardly, respectively. Fastening members 164 can be affixed to yet another flange 166 to matingly align with openings in a flange on the side panel assembly 168 . The side panel assembly 168 and the bottom panel assembly 170 are constructed in like manner. FIG. 9 is a top view depiction of two opposing end panel assemblies 148 and two opposing side panel assemblies 168 attached to the bottom panel assembly 170 . Note that the top-side orthogonal flanges such as 160 , 162 abuttingly engage each other to position the panel assemblies 148 , 168 squarely to the bottom panel assembly 170 . Preferably, the corner flanges are diagonally shaped to provide the mitered corners depicted in FIG. 9 . The completely assembled forms advantageously permit constructing all four sides and the bottom of the enclosure 102 in a monolithic pour.
In the foregoing illustrative embodiments the shelter 100 is installed so that its entry 109 is flush with grade 106 . In some embodiments the grade 106 can be an existing concrete floor, such as the fire pit 138 1 ( FIG. 5 ) installed on concrete patio and the like. In that event it is advantageous to modify the concrete enclosure 102 to provide concrete extensions upward to the grade so that the concrete enclosure 102 can be tied to the existing concrete floor. The existing concrete floor is drilled in multiple places to receive reinforcement rods (such as rebar) before pouring the enclosure 102 , to tie the newly poured concrete enclosure 102 to the existing concrete floor.
The various features and alternative details of construction of the apparatuses described herein for the practice of the present invention will readily occur to the skilled artisan in view of the foregoing discussion, and it is to be understood that even though numerous characteristics and advantages of various embodiments of the present invention have been set forth in the foregoing description, together with details of the structure and function of various embodiments of the invention, this detailed description is illustrative only, and changes may be made in detail, especially in matters of structure and arrangements of parts within the principles of the present invention to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed. | An apparatus and associated method contemplating an underground shelter having an open-top enclosure and a base. A linkage assembly selectively moves the base between an opened position and a closed position. A lifting mechanism lifts the base in opposition to a force of gravity on the base in the opened position. A concealment object is supported upon the base to conceal the existence of the underground shelter below. | 4 |
FIELD OF THE INVENTION
This invention relates to a method and apparatus for utilizing a cryogen including the manipulation, management and control of a cryogen. Cryogen can be utilized in the production of frozen and/or solidified small volumes of desired substances. The small volumes of solidified substances, also called pellets or granules in prior art, are hereinafter referred to as units.
The invention also relates to a method and apparatus for the manipulation, management, and control of the main body of the cryogen in combination with its internal currents.
BACKGROUND OF THE INVENTION
The desire for small volumes of substances, individually frozen or solidified has become greater as the technology has improved and the awareness and availability of such a product has increased. This demand includes food type products, bioactive products, chemical products, and in general any liquid, semi-liquid, semisolid or solid that may be desired to be frozen or solidified in small individual units. Small individual units do not demand the thawing of a large amount of product for utilization. Measurability, novelty, convenience, reduced waste, higher quality, ease of use, flowability, handling, minimizing cellular damage, and maximizing product efficacy are also advantages that industry is discovering with small frozen or solidified units. This demand has created a need for a product that has reasonable consistency of size, shape and other physical characteristics.
In the field of bio-active products, small frozen or solidified units have significant advantages. The freezing process is very fast and results in minimal cellular and structural damage, which provides maintenance of the desired bioactive characteristics.
The rapid freezing minimizes cellular damage caused by the formation of ice crystals, normally associated with freezing. Bioactive products are often freeze dried for storage. The characteristics of the units make them excellent for freeze drying. The more consistent the size and form of the units, the more favorable they are for a freeze drying process.
One of the advantages of a small volume of frozen or solidified product is that it can be made to flow like ball bearings (flowability). Thus, the handling of specific amounts of units that may vary with demand is possible. Agglomeration and deformed individual units inhibit the ability to flow as desired.
Measurement and utilization is also an important feature. If an average weight of the product is known, a specific amount can be utilized without thawing a larger block of product. The thawing of the desired amount of product is faster as a direct result of the relatively large surface area per unit of weight as compared to a frozen block of product. Many characteristics are improved significantly as a result of the rapid freezing or solidification of the small volume of liquids.
There is prior art in the field of production of frozen units by utilizing a cryogenic liquid. Much of the known art utilizes a particular cryogenic liquid, such as Liquid Nitrogen (LN2).
The main problem with the prior art is that the small volumes of substance are introduced into the cryogen with relatively little consideration of the manipulation and management of the cryogen itself. This results in the formation of random or poorly formed units. Creation of deformed units is commonly referred to as the “popcorn” effect. The units look like “popcorn” rather than smooth spheres.
Consistency of size, structure, texture and surface quality as well as control of agglomeration has not been able to be a manageable and controllable feature previously.
All of these variances result from the inability to control and manage the rapid heat transfer that occurs in the process. This rapid heat transfer results in remarkably violent gasification, which results from introduction of a relatively warm substance into the extremely cold cryogen. Gasification occurs at the interface between the cryogen and the forming units. Violent gasification results in cavitations at the surface of the cryogen resulting from the creation of gas bubbles, which can break the surface of the cryogen. Gas bubbles bursting at the surface of the cryogen can lead to incomplete and non-uniform immersion of the introduced substance into the cryogen. It also causes the units to violently interact. This violent interaction results in significant structural alterations of the units.
Agglomeration is also often a problem as the rapidly forming units often combine with other units resulting in multiple units combining and solidifying together. This agglomeration affects the flowability of the product as well as affecting other desired qualities
The relevant prior art is referenced as follows:
Canadian Patent #937450:
This patent describes the deformation that would naturally occur when a small volume of liquid is entered into a body of cryogenic material.
Canadian Patent #964921:
This art describes a small volume of liquid being introduced into an unmanaged and static body of cryogenic liquid.
Canadian Patent #1217351 and U.S. Pat. No. 4,655,047:
This patent describes the improved formation frozen pellets. This patent describes the introduced liquid relative to speed into the body of cryogenic liquid.
Canadian Patent #2013094 and U.S. Pat. No. 4,982,577:
This patent identifies the previous patents' lack of ability to control the exposure of the cryogenic liquid to external heat sources and thereby the subsequent waste of the cryogenic liquid. Although it establishes a good method of handling the liquid for the purposes of cost, it does not identify, mention or claim the benefits of a process of manipulation of the fluid dynamics of the cryogenic liquid to produce the ability to manage the characteristics of the introduced liquid as it solidifies.
U.S. Pat. No. 4,687,672:
This patent describes a freezing of large volume of product and its subsequent fracturing and grinding to produce a granular product.
U.S. Pat. No. 5,126,156:
This art describes a liquid being introduced into a cryogenic liquid without any reference to manipulation or management of the cryogenic liquid only referring to the removal of the pellets from the liquid after freezing and a screening process to extract only the pellets from the liquid via an auger in a similar fashion to Canadian patent 964921.
U.S. Pat. No. 6,000,229:
The art is basically a tub of cryogen with an introduction point of cryogen. In addition an auger for the removal of solidified pellets. There is not any attempt to manage the heat transfer, gasification or other destructive aspects.
Generally, the prior art in the field focuses on the actual small volume of liquid being introduced and the handling and removal of subsequently frozen product from the liquid cryogen. The prior art typically does not identify or discuss what actually occurs within the body of the cryogen or any methods or apparatus for managing the heat transfer and gasification that directly affects the structure and formation of the pellet being produced.
OBJECTS OF THE INVENTION
The synergistic effects of the type of management of the present invention include but are not limited to:
a) The dispersion of gas produced by the heat transfer between the thermally different introduced substance and cryogen. b) The dispersion of the heat transfer between the introduced substance and cryogen into the general body of the cryogen. c) Maintaining a physical distance between individual units such that the destructive aspects of physical interactions are minimized.
This enables the improved management, control and determination of the desired characteristics of the individual units. The characteristics managed are the shape, size, surface texture, deformation, frozen satellites, fines, and agglomeration of the introduced units as they are frozen or solidified.
Accordingly, several objects and advantages of the present invention include the manipulation and subsequent management of the cryogen utilized in the solidification of a series and/or multiple units of small volumes of a substance introduced into the cryogen. In general practice the cryogen utilized may be Liquid Nitrogen (LN2) or other suitable low temperature liquid.
Accordingly a primary objective of the present invention is the creation of the synergistic effects resulting from a method and apparatus for the manipulation and management of both the general fluid body (Fluid Body Movement) as well as the internal fluid dynamics (Currents) of the cryogen. These synergistic effects are utilized to control the characteristics of the frozen unit resulting from the introduction of that unit into the body of cryogen, such as Liquid Nitrogen (LN2). The controlled characteristics may include the surface structure, agglomeration, fines, satellites, average size, roundness and the prevention of ice crystallization.
Another object of the present invention is the physical movement of an introduced unit out of the introduction area of subsequently introduced units as a result of the unit being carried by the flow of the LN2.
Another object of the present invention is the reduction of physical interaction of forming and formed units with each other thereby avoiding the obvious physical damage that the firmer formed unit would cause to the forming units.
Another object of the present invention is to facilitate the dispersion of the gasification resulting from the interface between the small introduced unit and the cryogen. This dispersed gasification also assists in the enhancement of currents within the body of the cryogen.
Another object of the heat and gasification dispersion resulting from operation of the present invention is faster heat transfer from the introduced units into the liquid cryogen, as a result of increased direct contact between the forming unit and the LN2.
Another object of gas dispersion resulting from operation of the present invention is the minimizing of physical damage done as a result of the violent gasification on the forming unit.
Another object of the invention is the ability to regulate properties of the units, including these characteristics of the solidified or frozen unit, as the market requires. Properties can range from “popcorn” type products with or without agglomeration to smooth sphere like units that are individual in nature and of primarily similar size and shape.
An additional object of the invention is the utilization of a recycling system to create the desired flow of the cryogen.
An additional object of the invention is the utilization of a sloped raceway of varying designs to maintain the flow of the cryogen.
Another object of the invention is the length of the raceway. The length of the raceway, from the point of introduction of units into the cryogen to the point of units/cryogen separation at the removal mechanism for said units, can be calculated utilizing cryogen flow speed and desired retention time of the units in the cryogen.
Another object of the invention is the encouragement or discouragement of the internal currents within the body of the cryogen as a result of the recycling process to assist in desired results.
Additional objects, advantages, and other novel features of the invention will be set forth in part in the description and scientific explanation that follows and in part will become apparent to those skilled in the art upon examination of the following or may discerned from the practice of the invention.
The prior art does not manipulate, manage or utilize any of the described factors that occur in the cryogen. Previous patents simply introduce a unit into a body of cryogen. The gasification of the LN2 is sufficiently violent that the introduced unit appears to float or levitate on top of the LN2 as a result of the lift power of the gasification. This occurs in spite of the fact that units, in general, are heavier than the LN2. The units at the surface or near the surface are a combination of individual units in all three stages of formation moving violently and randomly. With the violent gasification and the combination of all stages of formation in close proximity it can easily be understood by anyone skilled in the art why the deformation, damage, fragmentation and agglomeration and other characteristics result.
To achieve the foregoing and other objects and advantages, and in accordance with the purposes of the present invention as described herein, a method and apparatus for producing the desired synergistic effects by manipulation of both the body and internal fluid dynamics of the cryogen utilized in the production of a free flowing frozen or solidified product resulting from the introduction of small volumes of liquid called units into the body of liquid cryogen.
SUMMARY OF INVENTION
The cryogen, preferably Liquid Nitrogen (LN2), may be drawn from a reservoir or sump at the bottom of the apparatus, by a means to remove said cryogen from the reservoir, such as a recycling system. The recycling system may comprise one or more augers; however, other recycling methods could be utilized. One or more augers may be utilized depending upon desired results. Multiple augers can provide a greater recycling volume as well as increased internal currents. An apparatus which creates a suction effect, or another means to elevate the cryogen from the reservoir may be suitable.
The recycled LN2 may be moved substantially vertically or upwards from the sump by rotation of an auger. The upward motion of the cryogen may result in a bubbling spring effect when the cryogen begins to transition to horizontal flow. Also, there may be internal currents created within the body of the cryogen that are initially caused by the auger or other recycling system.
A cryogen auger (as example of pumping methodology) does not have to be completely vertical however the preferred arrangement for lift is an auger that is substantially vertical with a plurality of flutes to be machined at a preferred angle of about 14 degrees from center with a quantity of flute flights of between about 8 and 10 per auger. The flutes preferred spacing is about 2.5 inches apart. The most preferred condition is a substantially vertical auger with a flute angle of 14 degrees from center with a quantity of flute flights of 8 with a spacing between flutes of 2.5 inches. If it is decided to employ an auger angle other than substantially vertical all flute angles and quantity of flutes thereof can be adjusted accordingly to offset the other than substantially vertical condition to allow for similar lifting volume of the cryogen. Large numbers of flutes are possible but can result in added vibration.
The vertical movement of the cryogen can develop into a fundamentally horizontal movement as it flows away from this transition point. At the transition point, back currents created by a vertical flow may dissipate and before the introduction of the small volume of substances at the introduction point. Once the flow evolves to a fundamentally horizontal flow the currents created by the recycling system disperse any minor gasification that results, resulting in a reasonably smooth surface on the LN2. The initial slope of the raceway at the product/cryogen interface will assist in the management of the speed and depth of the body of LN2 at this juncture with the preferred slope being between about −5 degrees (upward slope) up to about +15 degrees downward slope from the horizontal and the most preferred slope being +5 degrees downward from the horizontal. The subsequent angle of travel along the raceway beyond the interface point is preferred to be about +5 to about +15 degrees downward slope with the most preferred at +7 degrees.
If the current is too strong for the desired results, a screen or baffles can be utilized in advance of the introduction point of the small volumes of liquid to slow down the internal currents.
The distance of the exit of the recycling system at the point of transition from vertical to horizontal flow to the introduction point of the small volume of desired substance may be of sufficient distance such that the vertically moving LN2 being recycled converts to horizontal flow, thereby allowing any back eddies created by the vertical flowing liquid changing to a horizontal flow to dissipate and settle and become a non-factor in the current of the cryogen. This distance may be a factor associated with the maximum flow that the recycling system is capable of creating.
Once the LN2 has achieved a smooth surface and a substantially mono-directional horizontal flow, a desired substance may be introduced into the cryogen via a nozzle either under pressure or by gravity feed. The substance that is introduced may be a stream, or as individual measured droplets in varying degrees of frequency or precision depending upon the desired production outcome required. The height of the nozzle above the introduction zone may be adjustable due to desired characteristics of units. Preferably, the nozzle may be at a height sufficient to limit disruptive current resulting from introduction of the substance. Also, preferably the introduction of the substance will not cause upward spray of the cryogen. The horizontal movement of the LN2 can move the forming unit out of the introduction zone where subsequent units may be continuously introduced into the cryogen.
The inherent and artificial currents in the LN2 may disperse the gasification created by the introduction of the small volumes of relatively warm substance into the cryogen. Dispersion of this violent gasification at a point away from the introduction zone may enhance the internal currents within cryogen.
The LN2 can be guided down a sloped raceway. The raceway is constructed in a variety of formats depending upon the desired effect, substance being frozen or solidified, and desired retention time. The raceway may have a stainless steel surface, such as a “mirror” finish applicable in stainless steel polishing in the pharmaceutical industry, or other applications where a smooth finish is utilized. Finishes are typically determined pursuant to the regulatory bodies governing such things for individual industries, such as the FDA. These surface finishes can facilitate cleaning and disinfection of the system when required. In industry, often when there is a change from one product type to another it is essential that substantially the entire previous product be removed and cleaned. This is particularly imperative with bio-active products. In addition the smoother the surface the less the frictional resistance of the surface becomes a parameter in the movement of the cryogen or the individual units.
The cross section shape of the raceway may be an expanded “U” shape in order to facilitate cleaning and disinfection after use of the equipment. However, the raceway may be enclosed, such as a tube. A “U” shape can minimize corners that would affect the desired currents and flow for the cryogen. The “U” shape may also minimize damming or conglomerations of the units as they proceed down the raceway.
One embodiment of a raceway may be a spiral raceway. The slope of the raceway can be a function of the desired speed of the body of LN2 that is desired. The length of the spiral can be a function of the desired retention time of the forming and formed units. The longer the raceway or spiral the greater the retention time of the units. The slope of the spiral may also be a function of the desired retention time of the units and the desired speed of the cryogen. A greater the slope of the spiral will increase the rate of flow of the cryogen through the spiral.
The spiral formation can present additional benefits in that the currents and flow may not develop the opportunity to stabilize as easily as they would in a linear raceway.
Another embodiment of a raceway may be a series of linear raceways. The linear raceways may have a similar expanded “U” shape, or may be enclosed in a tube form.
The raceway can be made up of a series of cascading linear raceways, whereby a first linear raceway feeds into a receiving linear raceway running in a substantially different direction. This cascading of the cryogen from a first raceway into the receiving raceway may cause a general mixing of the cryogen and the units. This cascading effect may enhance the internal currents within the cryogen.
Again, the overall length of the embodiment of the linear raceway can be a function of desired retention time of the introduced units. A particular velocity of the cryogen and a specific length of raceway may result in different durations that the units are in the body of cryogen in advance of being removed by the extraction system.
The actual number of cascades utilized can be a function of the desired size of the equipment and the enhancement of the currents desired. However, the more cascades that are utilized the more that the internal currents may be enhanced.
A further embodiment of the present invention may be a linear raceway without any cascading or spiral action. Again, the slope and length of this design may be a function of desired speed and retention time of the units.
Upon exiting the raceway, the cryogen may travel through a moving screen or wire mesh belt. Preferably, the screen or wire mesh is of a conveyor belt style. The porous screen or mesh can be designed to allow the passage of the cryogen through it while removing the resultant solidified unit. The separation of the unit from the cryogen can be referred to as the removal point.
The escape of the gasification that has occurred in the cryogen may be via the same exit point as the units on the conveyor belt. Similarly, another advantage may be the utilization of heat transfer from the units to the gas as it escapes with the extraction of the units from the equipment.
Once passing through the screen or belt, the cryogen may be returned to the sump. There, the returned cryogen can be re-fed into the recycling system, and the process be made continuous.
EXAMPLES
In order to effectively describe the advantages of the invention, the physics and science of the introduction of a small volume of substance, preferably a liquid, semi-liquid, semisolid or solid, into a body of cryogen, such as LN2, is presented as follows.
Example 1
For this example water (H 2 0) will be utilized as the sample introduced liquid and Liquid Nitrogen (LN2) will be utilized as the cryogenic liquid.
Definitions and standards utilized:
Temperatures will be presented in Kelvin (K), with a conversion to Celsius (C) and Fahrenheit (F).
1. “Freezing Point” of water (H 2 0)=273.15 K 2. 273.15 K=32 degrees F=0 degrees C. 3. 1 degree Celsius=1 degree Kelvin 4. 1 gram (gm) of H 2 0=1 cubic centimeter (cc) of H 2 0 5. 1 cc.=1 cubic centimeter=1 gram of H 2 0 6. calories=1 calorie=the heat required to raise 1 gram of H 2 0 1 degree K 7. “Heat of Fusion” of H 2 0=79.7 cal/gm=79.7 cal/cc 8. “Vaporization Point” of Liquid Nitrogen (LN2)=77.4 K 9. “Heat of Vaporization” of LN2=2.7929 kJ/mol of LN2 10. 1 Mol of LN2=28.0134 gm. 11. 1 cal=4.184 joules 12. LN2=0.807 gm/cc=1.239 cc/gm. 13. 2.79 kJ/mol=23.83 cal/gm=29.526 cal/cc. 14. 1 cal converts 0.642 grn of LN2 to gas or 0.034 cc of LN2 to 5.91 cc of Nitrogen gas. 15. Expansion factor of LN2 liquid to a gas at vaporization temperature=174.6 volume of expansion.
When 1 gram (1 cc) of H 2 0 is introduced into a body of cryogen, being LN2, the heat transfer falls into three main categories:
1. The energy exchange in the lowering of the temperature of the introduced liquid to the point where a ‘Phase Change’ of the introduced H 2 0 occurs. 2. The energy exchange associated with the change of phase “Heat of Fusion” 273.15 K or 0 C or 32 F. 3. The energy exchange as the temperature of the units decreases to the desired exiting temperature, below 273.15 K, 0 C or 32 F.
Above the fusion temperature of water, or pre-solidification:
It requires 1 cal of energy release from the H 2 0 for each degree K of change above the “Fusion” temperature of the introduced water. Therefore it utilizes 0.0411 gm or 0.0339 cc of LN2 for each degree change with a subsequent gas release of 5.9134 cc of Nitrogen gas per degree of change of the H 2 0.
The physical properties of the introduced small volume of liquid may be very vulnerable during this stage as the unit retains its fluid properties, and hence, most susceptible to deformation, separation and fragmentation as well as agglomeration with previously introduced units and each other. As the crust is formed and solidification is initiated, any physical interaction may cause significant deformation of the forming unit, and possible agglomeration with other forming or formed units.
The phase change of the introduced liquid:
It requires 79.7 cal of heat exchange for the “Heat of Fusion” of the introduced product.
Therefore this heat exchange vaporizes 79.7×0.0411 gm or 79.7×0.0339 cc of LN2.
This result is the release of 471.28 cc of nitrogen gas.
In a practical application the “Heat of Fusion,” as well as the temperature at which the phase change occurs will vary depending upon the number of solids in the unit and the percentages of other liquids in the units such as lipids (fats), salts, spices, etc.
The physical properties of the forming unit at this stage can be vulnerable to a more limited extent. In a practical application the solidification may not occur as rapidly as in the H20 example. The presence of oils, solids, etc. in the liquid will result in the product being plastic or soft for a greater range of temperature. This results in a product that can be sensitive to physical damage such as deformation, as well as agglomeration with other units until complete solidification occurs.
Below the fusion temperature, or post-solidification:
It requires 1 cal of energy release from the H 2 0 for each degree of change below the “Fusion” temperature of the introduced water. Therefore, it utilizes 0.0411 gm or 0.0339 cc of LN2 for each degree change with a subsequent gas release of 5.9134 cc of Nitrogen gas per degree of desired change.
The ability of the unit, when solidified, to transfer heat may increase once it is solidified.
The physical properties of the frozen or solidified fluid below the fusion temperature are essentially constant, and additional damage or deformation is minimal, if even evident. A benefit to dispersion of gas produced and maintenance of distance between forming units is during the forming, pre-solidification, stage of the units.
In a model where the water is introduced at 278.15 K or 5 C or 41 F and the removal temperature is 165 K that is −108 C or −162 F, the gas production per cc of introduced H 2 0 input is:
Stage 1=5 cal×5.91 cc/cal=29.6 cc of gas released Stage 2=79.7 cal×5.91 cc/cal=471.28 cc of gas released Stage 3=108 cal×5.91 cc/cal=638.62 cc of gas released
This is a total of 1139.5 cc of gas produced within the body structure of the LN2 per gram or cc of H 2 0 introduced. As evident by this example, rapid Nitrogen buildup, or violent gasification, can result from the introduction of the relatively hot units into the LN2. This violent gasification may have a significant affect upon the internal currents and movement of the units within the body of the LN2.
Escaped gas can be utilized for additional cooling when the units are removed from the equipment on the conveyor screen.
Once the basic structure of the unit has taken place, the gas release of the individual unit slows down and the unit then sinks into the body of the LN2. Without management, virtually all the damage that would have been done to the physical characteristics would have occurred.
In a production system there is also a steady state loss of LN2 due to the operation of the equipment. The LN2 will vaporize even without the introduction of external units. This gasification is approximately 5,500 cc or 5.5 liters or 0.2 cubic feet per minute.
A system producing 200 lbs/hr and operating at an LN2 flow rate of 50% of motor capacity for a single auger LN2 pump and producing a product of approximately 15% to 25% solids will result in the following: The equipment-caused gasification would be approximately 5,500 cc of gas per minute, while the gas production from introduced units would be 1,730,000 cc of gas per min.
Example 2
A production system processing approximately 90 kilograms or 200 lbs of output per hour will release in excess of 1,730 liters or 61 cubic feet of gas per minute. Over 95% of that gas would be released normally at the interface of the introduced units and the LN2. This substantial gas release at the introduction point can lead to many adverse formation conditions, such as those previously mentioned.
In a production example, actual units range in size depending upon the introduction nozzles utilized and the particular characteristics of the liquid, semi-liquid, semisolid or solid. The average size may be from about 0.1 cc to 0.5 cc in size, but not limited to these sizes. The size of the unit will not affect the amount of gasification; however, the speed of the heat transfer will increase as the total surface area per total weight of product increases.
It can also be easily seen by anyone skilled in the art that violent gasification does occur and occurs very quickly at the interface between a forming unit and the LN2. In addition this violent gasification would affect the movement and interaction of units in the body of the cryogen. This type of reaction explains the deformation, size variances, surface characteristics and agglomeration that are noted to occur in the prior art.
BREIF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cutaway view of a representative apparatus of the present invention.
FIG. 2 is a cutaway view of the introduction point of the apparatus of the present invention.
FIG. 3 is a perspective view of showing different control means for the present invention.
FIG. 4 is a top view of the screen conveyor belt of the present invention.
FIG. 5 is a side view of the auger of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Having summarized various aspects of the present invention, reference will now be made in detail to the description of the invention as illustrated in the drawings and described in the scientific description. While the invention will be described in connection to these drawings and description, there is no attempt to limit the invention to the embodiment or embodiments disclosed herein. On the contrary, the intent is to cover all alternatives, modifications and equivalents included within the spirit and scope of the invention as defined by the appended claims.
Reference is now made to FIG. 1 showing the apparatus of the present invention. Cryogenic liquid may be stored in a sump ( 20 ), or reservoir, at the bottom gravitational location of the apparatus. The cryogen may be lifted to the entrance of the raceway ( 24 ) via one or more augers ( 22 ), as seen in FIG. 5 . Alternatively, an impellor-type pump may be used to created vertical flow of cryogen up to the raceway ( 24 ). The cryogen may then transition from vertical movement to horizontal flow, and initiate its travel down a sloped raceway ( 28 ).
The slope of the raceway can be a factor in the management of cryogen movement in the preferred embodiments for the slope being as follows for the top of the raceway at the product/cryogen interface. The length of the raceway, from the point of introduction of units into the cryogen to the point of units/cryogen separation at the removal mechanism for said units, can be calculated utilizing cryogen flow speed and desired retention time of the units in the cryogen.
The preferred slope can range from about −5 degrees (upward slope) to about +15 degrees (downward slope) from horizontal. Most preferably the slope is +5 degrees (downward slope from horizontal). The raceway slope can be produced to be adjustable across a desired range. Beyond the product/cryogen interface the raceway slope is preferred at about +5 to about +15 degrees downward slope with the most preferred at +7 degrees.
The cryogen with units contained therein can pass though a moving screen conveyor belt ( 30 ) that removes the solidified units from the cryogen. The conveyor belt ( 30 ) may be made of a screen, a wire mesh, or any suitable porous material that will filter the solidified or frozen units from the cryogen. The cryogen may then return to the sump ( 20 ) where it is recycled again.
The pumping capacity of the auger can be in excess of the ability of the cryogen in the sump to keep the entrance full of cryogen. If this operational condition was created, cavitations in the cryogen may occur if the auger is run too fast thereby introducing gas into the auger process. Cavitations in the cryogen may result in the vertical flow not being consistent. Also, an embodiment of the recycling system that consists of two or more augers thereby enables an increased flow without causing the undesirable cavitations and subsequent flow inconsistency.
The cryogen auger (as example of pumping methodology) does not have to be completely vertical however the preferred arrangement for lift is as follows: The auger can be substantially vertical with a plurality of flutes to be machined at about a 14 degree angle from center with a quantity of flute flights of between about 8 and 10 per auger. The flutes preferred spacing is about 2.5 inches apart. The most preferred condition is a substantially vertical auger with a flute angle of 14 degrees from center with a quantity of flute flights of 8 per auger, with a spacing between flutes of 2.5 inches. If it is decided to employ an auger angle other than substantially vertical all flute angles and quantity of flutes thereof can be adjusted accordingly to offset the other than substantially vertical condition to allow for similar lifting volume of the cryogen. Large numbers of flutes are possible but can result in added vibration.
Reference is now made to FIG. 2 in which the flow transition point is depicted. The cryogen may be lifted by the auger to enter the raceway ( 24 ). Motion of the auger ( 22 ) may create a circular and vertical direction ( 34 ) of the cryogen. Upon exiting the recycling system at the top of the auger, the direction of the fluid body movement is vertical and circular. The flow may change to a fundamentally horizontal flow. The transition from vertical to horizontal flow may result in the production of back eddies and reverse currents ( 36 ). Back eddies and reverse currents ( 36 ) can result in a spring bubbling-effect up into a body of cryogen then flowing in a horizontal direction.
These back eddies and reverse currents can be allowed to settle out as the fluid converts to basically horizontal flow ( 38 ) in advance of the introduction point ( 42 ) of the small volumes of a desired substance, such as liquid, semi-liquid, semisolid or solid. Upon introduction into the cryogen, these small volumes may be referred to as units. In another embodiment, a control means ( 40 ) may be introduced at the flow transition point to decrease the intensity of the back eddies and reverse currents. The control means may be a barrier, screen ( 25 ), baffle ( 21 ), or dam ( 23 ), as seen in FIG 3 . In a further embodiment, the apparatus may be adapted to inject a time delay for flow transition. In this embodiment, the auger may rotate with slower speed, there may be a dam before the introduction zone, or a diffusion pool may be added after the introduction zone.
The length of the raceway can determine the retention time of the units as a function of desired exiting temperature or required time necessary to ensure solidification in the cryogen given a particular speed of motion. In some cases the depth or speed of the cryogen can be adjusted to adjust retention time. In such cases a baffle, screen or a dam is placed in the raceway after the introduction point. A dam obviously increases the depth of the cryogen. A baffle aids in the direction of flow of the cryogen and units. A screen aids in the control of the internal currents in the cryogen.
The recycling of the cryogen can maintain a constant circular flow as it travels down the raceway back to the sump and up again to the entrance to the raceway ( 24 ).
The small volumes of substance can be introduced to the cryogen flow via a series of introduction nozzles ( 44 ) that introduce the liquid by streaming, or as individual droplets, either by gravity feed or under pressure. Droplets ( 46 ) can be predefined in volume by a specialized pump or can be determined by the particular surface tension of the liquid and form a droplet that can be released like a drip from a dripping tap.
The number of nozzles utilized for the introduction of small volumes of liquid, are a function of the engineering of the total unit. Preferably, multiple nozzles may be utilized. The actual number of nozzles utilized is a function of the total volume of liquid that the system can sustain while still maintaining the desired results. In general, the faster the speed of individual units being introduced, the faster the lateral movement of the cryogen required in order to achieve the results desired. In addition to pure cryogen velocity the higher the number of individual units being introduced the greater the surface area of the introduction point required.
The introduction point ( 42 ) may be positioned downstream from the introduction of the recycled cryogen such that eddies and back currents may have time to settle and a consistent forward flow is achieved. However, the introduction point ( 42 ) may be the same position as the entrance point ( 35 ). The distance from the recycled cryogen entrance ( 35 ) to the introduction point ( 42 ) can be dependent upon the maximum flow capacity desired for the equipment. An example of a desired result at the introduction point is a reasonably smooth surface on the flowing cryogen.
Preferably, the distance between the nozzles ( 48 ) is sufficiently distant such that the droplets or steams will not combine with each other before hitting the surface of the cryogen. Combination of droplets may also be a function of the height of the nozzles above the cryogen surface. Also, the nature of the product being processed can influence the combination of the droplets. The distance between nozzles, height above cryogen surface and nature of product being processed are variable and may be adjusted by user-designation.
When a droplet is introduced into a horizontally moving body of cryogen, the resulting unit may be moved away from the introduction point ( 42 ). The faster droplets are introduced, the faster the flow of cryogen that is required to move the unit ( 50 ) out of the way of the next introduced unit. Preferably, the unit is transported immediately from the introduction zone by the horizontal cryogen flow, thereby reducing the interaction between droplets and unformed units. The speed of the process may be controlled partly by the volume of cryogen recycled, the speed of the recycling of the cryogen, and the slope of the raceway.
Another management tool is the distance that the droplet will pass through before coming into contact with the LN2. The distance of the droplet height or individual liquid unit height from the body of LN2 can be dependent upon the liquid product to be frozen and could range from very low to very high. The preferred variance is from about 4 inches to about 36 inches above the cryogen. Depending on the product makeup (i.e. solid contents, viscosity and surface tension) and the desired results one wishes to achieve (i.e. consistent shaped pellets of varying degrees or misshapen and agglomerated pellets (i.e. Popcorn shaped) or many other combinations including frozen splatter) the height variance can be substantial. Also, liquid product pumping capacity may require establishment as to not overburden the system with too much liquid to be frozen and hence compromise the results desired or efficiencies of a certain type and size of unit/equipment. Testing of these parameters can be established to correlate to the needs of a particular end user and hence management for said requirements can be forecasted and built in to satisfying the existing and future needs of a user.
The distance of drop or droplet combined with its size and mass will to an extent demand that a particular depth and speed of LN2 be available in order to inhibit the droplet from hitting the actual bottom of the raceway in advance of the droplet forming its initial crust.
This methodology results in the gasification created by a particular unit not being added to the gasification of the next unit. In addition, increased flow may prevent the physical interaction of units while they are very susceptible to physical damage, as they are remote from each other.
The violent gasification results in cavitations. Cavitations ( 54 ) are individual bubbles that eventually break the surface of the cryogen. In effect the surface becomes covered with cavitations, which present a jagged surface to which the droplets contact. However, these cavitations can be remarkably destructive to droplets when they are introduced into the flow of cryogen. Maintenance of a smooth cryogen surface at the introduction area can be one of the essential parameters in managing the form and structure of the resultant units. This may be accomplished by maintaining a steady horizontal flow of cryogen ( 56 ).
As the heat is transferred from the units to the body of cryogen, the currents may move the actual cryogen molecules that are in the process of going through a change of phase or vaporization. Since the actual molecules that are absorbing heat are continually being moved away from the solidifying unit much of the gasification that would normally occur at the interface may be delayed or occur at a point away from the interface.
The internal currents, still active due to the recycling systems' motion, assist in the dispersion of the gas and heat from the interface. The gasification that occurs within the body of the cryogen can create additional currents that assist in the dispersion of subsequent gasification and heat. The movement of the gas bubbles through the fluid body of the cryogen enhances the existing currents and creates new ones. These currents can aid in the desired effect created by the currents. This can minimize physical damage as a result of the violent gasification. The movement of the gasification and heat away from the interface minimizes the normal encapsulation of the forming unit by the gasification. When a unit is encapsulated in gasification the speed of heat transfer is inhibited, as the gas does not absorb heat as quickly as the liquid cryogen absorbs heat. The result of minimizing encapsulation is that physical contact with the liquid cryogen is maximized, thereby maximizing heat transfer.
The newly forming units are physically moved out of the way of the next introduction of units as a result of this controlled lateral flow of cryogen, thereby minimizing the physical interaction of forming and formed units with each other. The continued flow down the sloped raceway can maintain this distance between the units. This may assist in controlling the agglomeration that would be expected to occur, as well as the physical interaction and resulting deformation or structural damage to the units that would result.
Depending upon the product and the management desired in general it is preferred that the cryogen flow be such that product is moved away from subsequent newly introduced product. However for some products minimal or substantial no flow of the cryogen may be advantageous. This is because even without any river type flow of the cryogen there is substantial currents and resulting movement thereof caused within the body of the cryogen as a result of the significant gasification that occurs at the interface between the introduced product and the cryogen. This substantial movement is over and above the great deal of movement that already occurs from the steady state gasification that occurs even without the introduction of the substance to be frozen.
The preferred rate of cryogen flow is relative to the individual liquid units to be frozen however for each product there can be established of a most preferred rate. This is ultimately accomplished through the testing of each individual liquid type product to be frozen and adjusting the parameter for cryogen flow accordingly to establish a most preferred rate. As well the amount of pumping capacity can vary with the size of each piece of equipment constructed and the number of pumping sources available. For some of what may be considered larger sized pieces of equipment produced (this is of course somewhat subjective to individual industry definition of larger scale) a preferred range for cryogen pumping capacity for example would be about 100 to about 150 liters of cryogen per minute into a river width of about 8 to 12 inches. A most preferred rate would be 120 liters per minute of pumping capacity with a river width of 10 inches. It is important to note that this technology is scaleable (small and large). For comparative purposes for smaller sized equipment than that as cited above the above ranges could be about 50% of those values (once again dependent upon industry definition and need). The cryogen depth can be managed to be within a preferred rate of from about 1 inch to about 3 inches deep by adjusting the cryogen flow rate and/or the horizontal slope of the tray and/or by introducing a downstream flood gate/dam or a narrowing of the raceway that will allow more or less cryogen to flow over it past its point of location depending upon the cryogen depth desired.
For example, a product of composition such as skim milk dropping simultaneously from approximately 48 nozzles from a height of between 20 and 25 inches into a flowing cryogen source moving along a 10″ trough at a +5 degree angle at the point of interface and then descending at a rate of approximately 2.5 feet per second for a time of approximately 20 seconds (residence time) will produce a consistent size and shape of pellet in a quantity of approximately 325 to 375 pounds per hour.
In specialized product situations, individual channels can be built in the raceway such that each nozzle utilized at the introduction point directs the droplets to follow a particular channel thereby stopping any horizontal interaction between units that were introduced at the same time.
When the gasification is removed remotely from the interface and mixed into the general body of the cryogen, the gasification can create additional random mini-currents within the body of the cryogen that assist in the general manipulation of the inherent currents and their subsequent effect as well as encouraging continued movement of the gasification.
This movement of the gasification away from the interface inhibits the initial floatation or levitation of droplets caused by the violent gasification ( 52 ), thereby minimizing the interaction of floating units that are randomly thrown around and have the possibility of hitting the sides of the raceway and/or each other.
The form of the raceway can also assist in this management and manipulation. A spiral raceway can continually change the direction of the flow of the cryogen thereby not allowing it to stabilize in a particular direction. A cascading raceway may cause the cryogen to cascade thereby enhancing internal currents and thereby fortifying random currents and flow. A linear raceway may allow the flow to stabilize.
The solidified units may be removed from the flow of cryogen via a conveyor belt screen with spacing in the screen such that the cryogen flows through the belt while the formed units do not flow through the belt. The belt may take the formed units to the exterior of the equipment where they are stored or utilized as desired. The exit of the cryogen gas due to evaporation or gasification from the equipment can be where the conveyor belt removes the solidified units. Therefore, the units after removal from the cryogen may be in an atmosphere of very cold gas. By adjusting the speed of the belt, the time that the units are exposed to this cold gas can be determined. There may be additional cooling of the units from this exposure to the expelled gas. | A method and apparatus for the manipulation and management process of cryogen such that it controls both the fluid body movement as well as internal currents within the cryogen. Small volumes of a desired substance introduced into this managed cryogen for the production of frozen or solidified pellets or granules are better managed as to shape, size, deformation, frozen satellites, fines and agglomeration and overall desired quality. These benefits result from the dispersion of the gas produced, as well as the heat transferred, resulting from the introduction of the relatively hot substance to the cryogen. The fluid body movement assists in maintaining a distance between the individual solidifying pellets or granules thereby minimizing deformation as a result of physical contact. The output characteristics and desired quality of the pellets can be more effectively controlled and managed, as desired. | 5 |
FIELD OF THE INVENTION
[0001] This invention is related to the controlled delivery of photothermal or other type of energy for treatment of biological or other tissue, and more specifically, a method, system and kit for causing a subdermal wound such that upon application of a growth factor, collagenesis and further repair and healing improvement of tissue is accelerated.
BACKGROUND OF THE INVENTION
[0002] Collagen is the single most abundant animal protein in mammals, accounting for up to 30% of all proteins. The collagen molecule, after being secreted by the fibroblast cell, assembles into characteristic fibers responsible for the functional integrity of tissues making up most organs in the body. The skin is the largest organ of the body occupying the greatest surface area within the human body. As age advances and as a result of other noxious stimuli, such as the increased concentration of the ultraviolet part of the electromagnetic spectrum as radiated from the sun, structural integrity and elasticity of skin diminishes.
[0003] Crosslinks between adjacent molecules are a prerequisite for this integrity of the collagen fibers to withstand the physical stresses to which they are exposed. A variety of human conditions, normal and pathological, involve the ability of tissues to repair and regenerate their collagenous framework. In the human, 13 collagen types have been identified. Of the different identifiable types, type I is the most abundant in skin where it makes up 80 to 90% of the total collagen connective tissue. This type of collagen, however, is less dynamic in the full-grown individual than its counterparts in which collagen is involved in active remodeling. In this case the normal collagen synthesizing activities in skin is relatively quiescent exhibiting slow, almost negligible, turnover.
[0004] The extra-cellular matrix of the various connective tissues, such as skin, consists of complex I macromolecules, collagen, elastin and glycosaminoglycans (GAGs). The biosynthesis of these macromolecules involves several specific reactions that are often under stringent enzymatic control. The net accumulation of connective tissues is thus, dependent upon the precise balance between the synthesis and the degradation of the connective tissue components.
[0005] Previous disclosures, such as U.S. Pat. No. 4,976,799 and U.S. Pat. No. 5,137,539 have described methods and apparatus for achieving controlled shrinkage of collagen tissue. These prior inventions have applications to collagen shrinkage in many parts of the body and describe specific references to the cosmetic and therapeutic contraction of collagen connective tissue within the skin. In the early 1980's it was found that by matching appropriate laser exposure parameters with these conditions, one had a novel process for the nondestructive thermal modification of collagen connective tissue within the human body to provide beneficial changes. The first clinical application of the process was for the non-destructive modification of the radius of curvature of the cornea of the eye to correct refractive errors, such as myopia, hyperopia, astigmatism and presbyopia. New studies of this process for the previously unobtainable tightening of the tympanic membrane or ear drum for one type of deafness have been made.
[0006] In addition to addressing the traditional method of collagen shrinkage wherein the ambient temperature is elevated within the target tissue by about 23 degrees Celsius, the “thermal shrinkage temperature” of collagen, T s , a novel method for obtaining controlled contraction of collagen at a much lower temperature has been developed. Evidence exists to elevate the mechanical role played by the GAGs in the collagenous matrix. Removing or altering these interstitial chemicals by enzymes or other reagents as disclosed in U.S. Pat. No. 5,304,169 considerably weakens the connective tissue integrity and influences the thermal transformation temperature (T s ). Shrinkage temperature may be defined, therefore, as the specific point at which disruptive tendencies exceed the cohesive forces in this tissue. This temperature, thus, makes this an actual measurement of the stability of the collagen bearing tissue expressed in thermal units.
[0007] The cause of wrinkles around the eyelids, mouth and lips is multifactorial: photodamage, smoking and muscular activity such as squinting and smiling all contribute. The end result is a general loss of elasticity, which is a textural skin condition as opposed to a skin redundancy or excess of skin tissue. The surgical injection of reconstituted collagen is commonly used in order to flatten the perioral lines. While oculoplastic surgeons may treat this problem around the eye inappropriately by blepharoplasty, it has been observed that even transconjunctival blepharoplasty for removal of prolapsed retrobulbar fat fails to address the fine periocular lines or wrinkles. Until recently, the main approach to treating these blemishes has been chemical peeling by means of trichloroacetic acid or phenol. Complications of chemical peels may include hypopigmentation, scarring, cicatricial ectropion and incomplete removal of the wrinkles.
[0008] Many patients are acutely aware of these cosmetic blemishes as evidenced by the large quantity of money spent each year in the U.S. and abroad upon home and spa remedies for a more youthful appearance. With the advent of laser technology as an alternative to chemical peels or dermabrasion, dermal ablation techniques with both the conventional carbon dioxide lasers and the high energy, short duration pulse waveform CO2 lasers, high tech solutions appear to provide substantial benefits to patients.
[0009] CO2 laser resurfacing is not a new technique. CO2 lasers have been used for several years, but regular continuous wave CO2 lasers can cause scarring due to the tissue destruction caused as heat as conducted to adjacent tissue. Even superpulse CO2 lasers produce excessive thermal damage. The Ultrapulse CO2 laser introduced by Coherent, Inc. is an attempt to assuage these drawbacks by offering a high energy, short duration pulse waveform limiting the damage to less than 50 microns allowing a char-free, layer by layer vaporization of the skin tissue.
[0010] All of the foregoing procedures depend for their success upon primary damage and the reparative potential induced by the inflammatory process in the tissue. Associated with inflammation are, of course, the four cardinal signs of inflammation of rubor (hyperemia), calor (thermal response), dolor (pain), and tumor or edema or swelling. Coincident with these manifestations is the risk of reduced resistance to infection. One must not forget that these collateral effects accompany a cosmetic enhancement procedure and, for the most part, are not associated with a therapeutic procedure. Therefore, the development of a more efficacious method would be beneficial in this regard.
[0011] Various undesirable skin conditions would be improved if the collagen underlying the region of the condition could safely be improved without damage to the overlying region. Wrinkles related to photodamage and acne scars are example of such conditions.
[0012] U.S. Pat. Nos. 4,976,709, 5,137,530, 5,304,169, 5,374,265, 5,484,432 issued to Sand, disclose a method and apparatus for controlled thermal shrinkage of collagen fibers in the cornea using light at wavelengths between 1.8 and 2.55 microns. However strong absorption of the laser energy by water limits the penetration depth to the most superficial layers of skin.
[0013] The CoolTouch (trademark) 130 laser system by CoolTouch Corp of Auburn, Calif., was first introduced at the Beverly Hills Eyelid Symposium in 1995. It utilizes a laser at a wavelength of 1.32 microns to cause thermally mediated skin treatment. In this device the treatment energy is targeted at the surface of the skin with in depth optical heating of the epidermis, papillary dermis, and upper reticular dermis. The energy is primarily absorbed in tissue water with a skin absorption coefficient of 1.4 cm-1, corresponding to an absorption depth of 0.71 cm. Scattering of the 1.32 micron wavelength light by skin microstructures alters the distribution of light from an exponential attenuation to a more complex distribution, which has much faster attenuation approximating an absorption depth of 0.1 cm. Most of the energy is absorbed in the first 250 microns of tissue. To prevent overheating of the epidermis pulsed cryogen spray precooling is used. U.S. Pat. No. 5,814,040, issued Sep. 29, 1998, describes a dynamic cooling method utilizing pulsed cryogen spray precooling. Skin treated with this device has improved texture and a reduction in wrinkles and scarring due to the long term renewal of dermal collagen without significant skin surface wounding.
[0014] U.S. Pat. No. 5,810,801 teaches a method and apparatus for treating a wrinkle in skin by targeting tissue at a level between 100 microns and 1.2 millimeters below the surface, to thermally injure collagen without erythema, by using light at wavelengths between 1.3 and 1.8 microns. The parameters of the invention are such that the radiation is maximally absorbed in the targeted region. The invention offers a detailed description of targeting the 100 micron to 1.2 mm region by utilization of a lens to focus the treatment energy to a depth of 750 microns below the surface. Because of the high scattering and absorption coefficients, precooling is utilized to prevent excess heat build up in the epidermis when targeting the region of 100 microns to 1.2 mm below the surface. The wavelength range of use is 1.3 microns to 1.8 microns in order to avoid the wavelength range of Sand. However the wavelength range of 1.4 to 1.54 microns and the range between 2.06 and 2.2 microns have identical effective attenuation coefficients in skin. Also the range from 1.15 to 1.32 microns has a fairly uniform effective attenuation coefficient in skin of about 6 to 7 cm-1. The effective attenuation length in skin for the range of wavelengths of 1.3 to 1.8 microns varies from 6 cm-1 at 1.3 microns to 52 cm-1 microns, corresponding to penetration depths in skin of 200 microns to 2 millimeters. Specific laser and cooling parameters are selected so as to avoid erythema and achieve improvement in wrinkles as the long term result of a new collagen formation following treatment.
[0015] Kelly et al, report improvement in skin due to collagen remodeling after treatments with an Nd:YAG laser at 1.32 microns and cryogen spray precooling. In this case the method was designed to provide a series of treatments with parameters selected to produce erythema and mild edema, with some improvement in facial rhytids several months following a series of treatments. However, there is a risk of pigmentary change or transient pitted scarring because of the high fluence level of the laser, greater than 30 joules per square centimeter in 20 millisecond exposures, and the high level of pulse cryogen cooling.
[0016] Mucini et al. reported effective dermal remodeling using a 980 nm diode laser with a spherical handpiece which focused irradiation into the dermis avoiding the high scattering and absorption characteristic of longer wavelengths. The device requires a small lens of a few millimeters in contact with skin and results in a slow procedure when used for facial areas.
[0017] Ross et al., reported the use of an Erbium:YAG laser operating at a wavelength of 1.54 microns fired in a multiple pulsed mode has been described for eliciting changes in photodamaged skin. A chilled lens in contact with skin at the treatment site was used in an attempt to spare the epidermis. Treatment occurred during a period of several seconds with a sequence of cooling and heating with the laser and handpiece. At 1.54 microns the optical penetration depth 0.55 mm and the authors reported that the surface must be chilled before the laser exposure requiring a complex method of cooling and laser exposure. The authors state that a more superficial thermal injury may be needed than could be achieved, and that there are increased patient risks because it would demand more accurate and precise control of heating and cooling.
[0018] Bjerring et al, reported the use of a visible light laser, operating at 585 nm wavelength, to initiate collagenesis following interaction of laser energy with small blood vessels in skin.
[0019] Other methods of creating subepidermal wounding may utilize electrical current, ultrasonic energy or non-coherent light sources. In all of these methods, including those using lasers, collagen remodeling is a long-term minimal response to the application of energy. Since the objective is a non-invasive or minimally invasive procedure the stimulation of collagenesis must be below the threshold for creating an open wound, resulting in a minimal treatment.
[0020] U.S. Pat. No. 5,599,788 describes a method of producing recombinant transforming growth factor .beta.-induced H3 protein and the use of this protein to accelerate wound healing. The protein is applied directly to a wound or is used to promote adhesion and spreading of dermal fibroblasts to a solid support such as a nylon mesh which is then applied to the wound.
[0021] It is heretofore unknown to combine the adverse effect caused by excessive photothermal, mechanical or other type of energy applied to skin or other tissue coupled with a topical or other administration of growth factor(s) or wound healing factor(s) in order to amplify the natural stimulation of growth or collagenesis caused by the wound.
OBJECTS AND ADVANTAGES OF THE PRESENT INVENTION
[0022] The object of this invention is to provide a method and device for improving skin by treating layers of skin without damaging the surface or deep skin layers. It is another object of this invention to provide a method and device for improving acne scars or photodamaged skin without causing a surface injury to skin. It is another object of this invention to provide a method and device for accelerating the collagenesis after treating skin without damaging the surface of skin.
[0023] It is yet a further advantage and object of the present invention to combine the adverse effect caused by excessive photothermal, mechanical or other type of energy applied to skin or other tissue coupled with a topical or other administration of growth factor(s) or wound healing factor(s) in order to amplify the natural stimulation of growth or collagenesis caused by the wound.
[0024] The present invention circumvents the problems of the prior art and provides a system for achieving erythema and mild edema in an upper layer of skin without the risk of high fluence levels or surface wounds. The invention offer advantages over existing devices by allowing the use of lower fluence levels resulting in faster treatments and less cost. Collagen remodeling is induced by distributing the therapeutic energy over a series of more benign treatments spaced weeks apart. The collagen remodeling is further enhanced by the use of a transforming growth factor which accelerates the wound healing response. Th growth factor is applied topically in a media which will act on the skin.
[0025] Numerous other advantages and features of the present invention will become readily apparent from the following detailed description of the invention and the embodiments thereof, from the claims and from the accompanying drawings.
SUMMARY OF THE PRESENT INVENTION
[0026] The present invention is a method and apparatus for skin or other tissue treatment, using a source of thermal energy, which may be electromagnetic radiation, electrical current, or ultrasonic energy, to cause minimal-invasive thermally-mediated effects in skin or other tissue leading to a wound-healing response, in conjunction with topical agents which accelerate collagenesis in response to wound healing. The dosage and time period of application are adjusted to prevent external or surface tissue damage.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] [0027]FIG. 1 is a cross-section view of typical skin tissue.
[0028] [0028]FIG. 2 is a graph demonstrating the temperature gradient through a portion of the skin as a function of both the wavelength of incident laser energy and the depth of laser radiation penetration.
[0029] [0029]FIG. 3 is a schematic view of a microscope mounted scanner for a temperature controlled collagen shrinkage device used in the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0030] The description that follows is presented to enable one skilled in the art to make and use the present invention, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be apparent to those skilled in the art, and the general principals discussed below may be applied to other embodiments and applications without departing from the scope and spirit of the invention. Therefore, the invention is not intended to be limited to the embodiments disclosed, but the invention is to be given the largest possible scope which is consistent with the principals and features described herein.
[0031] It will be understood that while numerous preferred embodiments of the present invention are presented herein, numerous of the individual elements and functional aspects of the embodiments are similar. Therefore, it will be understood that structural elements of the numerous apparatus disclosed herein having similar or identical function may have like reference numerals associated therewith.
[0032] Definitions
[0033] An “absorption coefficient” of a substance is a measure of the fraction of incident light that is absorbed when light is passed through the substance. The absorption coefficient (typically in units of cm −1 ) varies with the nature of the absorbing substance and with the wavelength of the light.
[0034] “Collagen” as used herein refers to any of the several types of collagen.
[0035] Collagen biosynthesis is said to be “inhibited’ when cells treated with the claimed methods secrete collagen at a rate that is less than about 70% of that of untreated cells. Preferably, treated cells secrete collagen at a rate that is less than about 50%, and more preferably less than about 30% of the rate at which untreated cells secrete collagen.
[0036] Collagen biosynthesis is said to be ‘stimulated’ when cells treated with the claimed methods secrete collagen at a rate that is greater than about 110% of the rate at which untreated cells synthesize collagen. Preferably, treated cells secrete collagen at a rate that is about 150%, and more preferably greater than about 200% greater than that of untreated cells.
[0037] “Monochromatic” light is of one wavelength or a narrow range of wavelengths. If the wavelength is in the visible range, monochromatic light will be of a single color. As used herein, “monochromatic” refers to light that has a bandwidth of less than about 100 nm. More preferably, the bandwidth will be less than about 10 nm, and most preferably less than about 1 nm.
[0038] “Non-coherent light energy” is light that is non-laser. Unlike laser light, which is characterized by having its photon wave motions in phase, the wave motions of the photons that make up non-coherent light are in a randomly occurring phase order or are otherwise out of phase.
[0039] A “wound” as used herein, refers to any damage to any tissue in a living organism. The tissue may be an internal tissue, such as the stomach lining or a bone, or an external tissue, such as the skin. As such, a wound may include, but is not limited to, a gastrointestinal tract ulcer, a broken bone, a neoplasia, and cut or abraded skin. A wound may be in a soft tissue, such as the spleen, or in a hard tissue, such as bone. The wound may have been caused by any agent, including traumatic injury, infection or surgical intervention.
[0040] A “growth factor” as used herein, includes any soluble factor that regulates or mediates cell proliferation, cell differentiation, tissue regeneration, cell attraction, wound repair and/or any developmental or proliferative process. The growth factor may be produced by any appropriate means including extraction from natural sources, production through synthetic chemistry, production through the use of recombinant DNA techniques and any other techniques, including virally inactivated, growth factor(s)-rich platelet releasate, which are known to those of skill in the art. The term growth factor is meant to include any precursors, mutants, derivatives, or other forms thereof which possess similar biological activity(ies), or a subset thereof, to those of the growth factor from which it is derived or otherwise related.
[0041] [0041]FIG. 1 is a cross-section view of typical skin tissue. The uppermost layer 98 of typical skin tissue is composed of dead cells which form a tough, horny protective coating. A thin outer layer, the epidermis 100 and a thicker inner layer, the dermis 102 . Intertwining S-like finger shaped portions 104 are at the interface between the epidermal papillary layer 106 and the dermal papillary layer 108 , and extend downward. Beneath the dermis is the subcutaneous tissue 110 , which often contains a significant amount of fat. It is the dermis layer which contains the major part of the connective collagen which is to be shrunk, in a preferred embodiment at an approximate target depth of between about 100 and 300 microns, according to the method of the present invention, though viable collagen connective tissue also exists to a certain degree in the lower subcutaneous layer as well. Other structures found in typical skin include hair and an associated follicle 112 , sweat or sebaceous glands and associated pores 114 , blood vessels 116 and nerves 118 . Additionally, a pigment layer 120 might be present. It will be understood that the drawing is representative of typical skin and that the collagen matrix will take different forms in different parts of the body. For example, in the eyelids and cheeks the dermis and subcutaneous layers are significantly thinner with less fat than in other areas. The target depth will be a function of the amount of scattering in the particular skin type and the associated absorption coefficient of the tissue. Furthermore, in some cases the actual target depth will correspond to one half the thickness of the subject tissue. For example, the target depth of tissue ½ inch thick might be about ¼ inch below the surface of the skin.
[0042] A. Damage to Tissue
[0043] Optimum Wavelength: 1.3-1.4 Microns
[0044] Methods and devices for modulating collagen biosynthesis are provided. The methods involve focusing non-coherent light energy of a predetermined wavelength to a target site where collagen biosynthesis can potentially occur. Depending upon the particular wavelength employed, collagen biosynthesis is either inhibited or stimulated. Generally, wavelengths in the red and near-infrared portion of the electromagnetic spectrum stimulate collagen biosynthesis, while longer wavelengths inhibit collagen biosynthesis.
[0045] In a preferred embodiment, to inhibit collagen biosynthesis, light energy of a wavelength greater than about 1.0 μm, preferably about 1.06 μm, is delivered to the target site for a time period sufficient to accomplish the inhibition. In a preferred embodiment, stimulation of collagen biosynthesis occurs when light energy at 640 nm or 900 nm is delivered to a target site for a time period sufficient to accomplish the stimulation.
[0046] The optimal wavelength within these ranges is influenced by whether the light energy must pass through overlying tissue before reaching the target site. In such cases where the target site is shielded by other tissue, the light energy is transmitted through the shielding tissue and focused on the target site so that the desired energy level is obtained at the target site. Because transmission of light through tissue is highly wavelength specific, one should choose a wavelength that is not highly absorbed by overlying tissue.
[0047] To modulate collagen biosynthesis, an amount of light energy of an appropriate predetermined wavelength is delivered to the target site that is sufficient to have the desired stimulatory or inhibitory effect. The amount of energy delivered to a target site is a function of several factors, including the output of the light source, the energy flux at the target site as determined by the source output and the degree of focusing achieved by the light delivery apparatus, and the time period for which the target site is exposed to the light energy. Another factor, discussed below, is the nature of any tissue overlying the target site.
[0048] The appropriate combinations of energy flux and time period for a desired effect on collagen biosynthesis can be determined empirically. For example, one can determine the effect on collagen biosynthesis of irradiating cells growing in tissue, preferably in monolayers, with light energy of a given wavelength, energy flux, and time period.
[0049] In general, the desired energy density delivered to the target site is between about 1.0×10 3 and 1.6×10 3 Joules cm −2 . Preferably, the energy density at the target site is about 1.1×10 3 Joules cm −2 . For most applications, the amount of energy delivered to the target site should be sufficient to modulate collagen biosynthesis, but should not be so great as to cause a significant decrease in cell proliferation. For example, 1.7×10 3 Joules cm −2 of 1064 nm laser light is known to inhibit fibroblast proliferation. Thus, an energy that is between about 1.1×10 3 and about 1.7×10 3 Joules cm −2 is preferred.
[0050] To achieve the desired energy density, the light energy is delivered to the target site for a sufficient time period. The time period necessary depends on the energy flux delivered to the target site by the light delivery apparatus. The light can be delivered as a single pulse or as a multiplicity of pulses. Often, the use of short pulses is preferred, as the shorter pulses cause less undesirable heating of the tissues surrounding the target site than does a single pulse of longer duration. Preferably, a higher-power shorter-duration pulse is used, rather than a low-power long-duration pulse. Typical pulse durations are between about 0.01 and 1.0 seconds, most preferably about 0.I seconds.
[0051] Light Delivery Apparatus
[0052] Many types of non-laser light sources are suitable for producing the noncoherent light that is used in the methods and apparatus of the present invention. For example, one can employ polychromatic light sources such as heated lamp filaments or gas filled vacuum tubes. Commercially available light sources are discussed in, for example, LaRocca, A., “Artificial Sources,” In Handbook of Optics , Vol. 1, Ch. 10, Bass et al., eds., McGraw-Hill, New York, 1995, pp. 10.3-10.50, and references cited therein.
[0053] If a polychromatic light source is used, the light energy is preferably made monochromatic or nearly monochromatic by suitable methods known to those of skill in the art. For example, one can direct the polychromatic light through a filter or a series of filters that transmits only light of the desired wavelength or range of wavelengths. Suitable filters are described in, for example, Dobrowolski, J. A., “Optical Properties of Films and Coatings,” In Handbook of Optics , Vol. 1, Ch. 42, Bass et al., eds., McGraw-Hill, New York, 1995, pp. 42.342.130, and references cited therein. Bandpass filters are reviewed, for example, in Macleod, H. A., 7hin film Optical E 71 ters , McGraw-Hill, New York, 1986; ‘Metal-dielectric Interference Filters,” in Physics of 7 hin Films , Hass et al., eds., Academic Press, New York, 1977, vol. 9, pp. 73-144; Barr, “The Design and Construction of Evaporated Multilayer Filters for Use in Solar Radiation Technology,” in Advances in Geophysics , Drummond, ed., Academic Press, New York, 1970, pp. 391-412).
[0054] In a preferred embodiment, a monochromatic or nearly monochromatic light source is used. By choosing a light source that emits monochromatic or nearly monochromatic light, the need to filter or focus the light to the desired wavelength is eliminated. Several types of monochromatic or nearly monochromatic light source are known to those of skill in the art. See, e.g., LaRocca, supra., for types and sources of monochromatic light sources.
[0055] Light-emitting diodes (LEDs) are a preferred light source for use in the claimed invention. LEDs are described, for example, in Haitz et al., “Light-Emitting Diodes,” In Handbook of Optics , Vol. 1, Ch. 12, Bass, M., ed., McGraw-Hill, New York, pp. 12.1-12.39. Both surface and edge emitters are commercially available, in continuous and pulse-operated modes. Commercially available LEDs that are useful in the claimed methods emit wavelengths of 830, 904, 1060, 1300, and 1550 nm. In preferred embodiments of the present invention, the 830 and 904 nm LEDs are useful for stimulating collagen biosynthesis, while in other preferred embodiments of the present invention, the 1060, 1300, and 1550 nm LEDs are appropriate for inhibition.
[0056] Light energy used in the claimed methods is preferably collimated, in addition to being of a predetermined wavelength or range of wavelengths. Collimation can be achieved by any of several methods known to those of skill in the art. For example, passing light through fiber optics of various core diameters will achieve collimation. Suitable fiber optic instrumentation is available from EG&G Opto-Electronics of Salem, Mass. Optical fibers are described, for example, in Brown, T. G., “Optical Fibers and Fiber-Optic Communications,” In Handbook of Optics, Vol. U, Ch. 10, Bass, M., ed., McGraw-Hill, New York, pp. 10.1 et seq.
[0057] The light energy is focused to the target site as a spot having a diameter that is appropriate for the particular treatment being undertaken. Where inhibition of collagen biosynthesis in a relatively small area is used, the light is focused to a correspondingly small spot at the target site. Typically, the light energy is focused to a spot with a diameter in the range of about 0.25 to about 2.0 millimeters. The focusing step also concentrates the light to an energy flux that is sufficient to achieve the desired inhibition when delivered to the target site for an appropriate period of time.
[0058] Methods for focusing light to achieve a desired energy flux and spot diameter are known to those of skill in the art. For example, a focusing lens made of glass, silica, or refractory material such as diamond or sapphire is commonly employed. In a preferred embodiment, the focusing lens directs the non-coherent light energy to an optical fiber of an appropriate core diameter and composition. For example, a 100 μm diameter low-OH silica optic fiber is appropriate. A fiber that produces a relatively low amount of transmission loss is preferred, preferably less than about 15% loss over a length of up to ten meters. The fiber is typically mounted in a shaft for delivery of the non-coherent light energy to the tissue. The output end of the shaft is preferably fitted with an output tip that can dir maintaining the delivery end of the fiber a desired distance away from the tissue. This distance can be varied by substituting a longer or shorter output tip, or by slidably adjusting the position of the output tip on the shaft.
[0059] For some applications, it is desirable to use an output tip that directs the noncoherent focused light out of its side, rather than through the end of the fiber. Means for accomplishing this are known to those of skill in the art. For example, U.S. Pat. No. 5,129,895 describes the use of a reflecting surface at the end of the fiber combined with lens action on the fiber side.
[0060] The invention also provides an apparatus for modulating collagen biosynthesis according to the methods described herein. The apparatus comprises a source of noncoherent light energy, a means for collimating the light energy generated by the light source, and a means for focusing the collimated light energy to a target site. The apparatus delivers sufficient light energy to the target site to modulate collagen biosynthesis.
[0061] Therapeutic Applications
[0062] The claimed methods for modulating collagen biosynthesis are useful in treating many conditions. Depending upon the condition being treated, either inhibition or stimulation of collagen biosynthesis may be desired.
[0063] The invention also provides methods for stimulating collagen biosynthesis. These methods are also useful in the clinical setting. For example, stimulation of collagen biosynthesis is often desirable in the early stages of wound healing. The procedures employed are similar to those used for inhibiting collagen biosynthesis, except for the wavelength of light delivered to the target site. To stimulate collagen biosynthesis, one delivers light in the red or near-infrared range of the electromagnetic spectrum to the target site. For example, light energy at 640 nm or 900 nm stimulates collagen biosynthesis when delivered to a target site at specific energy densities and durations.
[0064] To enhance wound healing, collimated fight energy of an appropriate wavelength is delivered to the wound at an energy density sufficient to stimulate collagen biosynthesis. Ile light energy can be delivered as a single pulse, or more preferably, as a series of short pulses. The use of short pulses reduces the likelihood of undesired heating of the tissue. Preferably, the light energy delivered is sufficient to stimulate collagen biosynthesis, but is insufficient to inhibit cell proliferation.
[0065] [0065]FIG. 2 is a graph demonstrating the temperature gradient through a portion of the skin as a function of both the wavelength of incident laser energy and the depth of laser radiation penetration. No external cooling is used. The graph demonstrates a change in temperature (ΔT) of about 60 degrees Celsius and all curves are shown for the time point 1 millisecond following exposure to the laser energy. The graph shows three lines corresponding to laser wavelengths of 10.6 microns, 1.3-1.4 microns and 1.06 microns.
[0066] The present invention utilizes laser energy having a wavelength between about 1 and about 12 microns, more preferably between about 1.2 and about 1.8 microns, and more preferably about 1.3-1.4 microns. This type of laser energy is most frequently produced by a Nd:YAG, Nd:YAP or Nd:YALO-type laser. A laser operating at these wavelengths may either have a high repetition pulse rate or operate in a continuous wave mode. This laser has been investigated in the medical community as a general surgical and tissue welding device, but has not been used for collagen tissue shrinkage in the past. Indeed, the prior art teaches away from the use of laser energy at 1.3-1.4 microns for shrinking human collagen.
[0067] The Nd:YAG, Nd:YAP and Nd:YALO-type lasers are sources of coherent energy. This wavelength of 1.3-1.4 microns is absorbed relatively well by water, and as a result is attractive for tissue interaction. It is also easily transmitted through a fiber optic delivery system as opposed to the rigid articulated arm required for the CO 2 laser. Very precise methods of controlling laser systems and optically filtering produced light currently exist. By selecting the appropriate combination of resonance optics and/or antireflection coatings, wavelengths in the range of 1.3-1.4 microns and even 1.32-1.34 microns can be produced.
[0068] [0068]FIG. 3 is a schematic view of a microscope mounted scanner for a temperature controlled collagen shrinkage device used in the present invention. In this view, a laser console 60 is installed adjacent a floor-mounted microscope 62 . A fiber optic cable 64 conducts laser energy from the laser source to the scanner 66 . A laser delivery attachment 68 may be necessary to conduct the laser energy in an appropriate beam pattern and focus. In this embodiment of the invention, servo feedback 70 signals are also conducted along the fiber optic back to the laser console. The servo feedback signals could also be directed back to the laser console via an additional fiber optic or other wiring or cabling. This servo feedback may comprise thermal or optical data obtained via external sensors or via internal systems, such as a fiber-tip protection system which attenuates the laser energy transmitted, to provide control in operation and to prevent thermal runaway in the laser delivery device. Thus, a thermal feedback controller 72 will regulate the laser energy being transmitted. This controller can comprise an analog or digital PI, PD or PID-type controller, a microprocessor and set of operating instructions, or any other controller known to those skilled in the art. Other preferred embodiments can also be provided with additional features. For example, the surgeon or technician operating the laser could also manipulate an energy adjust knob 74 , a calibration knob 76 and a footpedal 78 . Thus, in a preferred embodiment, a very accurately adjustable system is provided which allows a surgeon to deliver laser energy via a computer controlled scanning device, according to instructions given by the surgeon or an observer inspecting the region of the skin where collagen is to be shrunk through a very accurate microscope. Once a region to be treated is located, the scanner can deliver a very precise, predetermined amount of laser energy, in precisely chosen, predetermined regions of the skin over specific, predetermined periods of time.
[0069] In a preferred embodiment, the invention utilizes an Nd:YAG laser at 1320 nm wavelength, (such as the CoolTouch 130, CoolTouch Corp., Auburn, Calif.) as the source of treatment energy. At 1320 nm the absorption depth in tissue is such that energy is deposited throughout the upper dermis, with most absorption in the epidermis and upper dermis, a region including the top 200 to 400 microns of tissue. The energy falls off approximately exponentially with the highest level of absorbed energy in the epidermis. Optical heating of skin follows exposure to the laser energy. If the time of exposure to the laser is very short compared to the time required for heat to diffuse out of the area exposed, the thermal relaxation time, than the temperature rise at any depth in the exposed tissue will be proportional to the energy absorbed at that depth. However, if the pulse width is comparable or longer to the thermal relaxation time of the exposed tissue than profile of temperature rise will not be as steep. Conduction of thermal energy occurs at a rate proportional to the temperature gradient in the exposed tissue. Lengthening the exposure time will reduce the maximum temperature rise in exposed tissue.
[0070] For example at 1.3 microns the laser pulse width may be set to 30 milliseconds and fluence to less than 30 joules per square centimeter. This prevents excessive heat build up in the epidermis, which is approximately the top 100 microns in skin. The papillary dermis can then be heated to a therapeutic level without damage to the epidermis. The epidermis will reach a temperature higher than but close to that of the papillary dermis.
[0071] The epidermis is more resilient in handling extremes of temperature than most other tissue in the human body. It is therefore possible to treat the papillary dermis in conjunction with the epidermis without scarring or blistering, by treating both layers with laser energy and allowing a long enough exposure time such that the thermal gradient between the epidermis and underlying layers remains low. In this way the underlying layers can be treated without thermal damage to the epidermis.
[0072] A wavelength of 1.3 microns is used in this embodiment to treat the middle layers of skin. Other wavelengths such as 1.45 or 2.1 microns may by used to treat more superficial layers of skin by this method. Visible light lasers, intense pulsed light sources, energy delivery devices such as electrical generators, ultrasonic transducers, and microdermabrasion devices may also be used to initiate a wound healing response without significant surface wounding. The use of growth factors in conjunction with these devices allows for more superficial treatments and improved response.
[0073] In one embodiment the invention utilizes an Nd:YAG laser at 1320 nm wavelength, (such as the CoolTouch 130, CoolTouch Corp., Auburn Calif.) as the source of treatment energy. At 1320 nm the absorption depth in tissue is such that energy is deposited throughout the upper dermis, with most absorption in the epidermis and upper dermis, a region including the top 200 to 400 microns of tissue. The energy falls off approximately exponentially with the highest level of absorbed energy in the epidermis. Optical heating of skin follows exposure to the laser energy. If the time of exposure to the laser is very short compared to the time required for heat to diffuse out of the area exposed, the thermal relaxation time, than the temperature rise at any depth in the exposed tissue will be proportional to the energy absorbed at that depth. However, if the pulse width is comparable or longer to the thermal relaxation time of the exposed tissue than profile of temperature rise will not be as steep. Conduction of thermal energy occurs at a rate proportional to the temperature gradient in the exposed tissue. Lengthening the exposure time will reduce the maximum temperature rise in exposed tissue.
[0074] The present invention also incorporates herein by specific reference, in their entireties, the following issued U.S. patents:
[0075] U.S. Pat. No. 5,885,274 issued Mar. 3, 1999 titled FLASH LAMP FOR DERMATOLOGICAL TREATMENT, U.S. Pat. No. 5,968,034 issued Oct. 19, 1999 titled PULSED FILAMENT LAMP FOR DERMATOLOGICAL TREATMENT, U.S. Pat. No. 5,820,626 issued Oct. 13, 1998 titled COOLING LASER HANDPIECE WITH REFILLABLE COOLANT RESERVOIR, U.S. Pat. No. 5,976,123 issued Nov. 2, 1999 titled HEART STABILIZATION, U.S. Pat. No. 6,273,885 issued Aug. 14, 2001 titled HANDHELD PHOTOEPILATION DEVICE AND METHOD.
[0076] The present invention also incorporates herein by specific reference, in their entireties, the following pending U.S. patent applications: application Ser. No. 09/185,490 filed Nov. 3, 1998 titled SUBSURFACE HEATING OF TISSUE, application Ser. No. 09/364,275 filed Jul. 29, 1999 titled THERMAL QUENCHING OF TISSUE.
[0077] B. Wound Healing and Growth Factors
[0078] When a tissue is injured, polypeptide growth factors, which exhibit an array of biological activities, are released into the wound where they play a crucial role in healing (see, e.g., Hormonal Proteins and Peptides (Li, C. H., ed.) Volume 7, Academic Press, Inc., New York, N.Y. pp. 231-277 (1979) and Brunt et al., Biotechnology 6:25-30 (1988)). These activities include recruiting cells, such as leukocytes and fibroblasts, into the injured area, and inducing cell proliferation and differentiation. Growth factors that may participate in wound healing include, but are not limited to: platelet-derived growth factors (PDGFs); insulin-binding growth factor-1 (IGF-1); insulin-binding growth factor-2 (IGF-2); epidermal growth factor (EGF); transforming growth factor-.alpha. (TGF-.alpha.); transforming growth factor-.beta. (TGF-.beta.); platelet factor 4 (PF-4); and heparin binding growth factors one and two (HBGF-1 and HBGF-2, respectively).
[0079] PDGFs are stored in the alpha granules of circulating platelets and are released at wound sites during blood clotting (see, e.g., Lynch et al., J. Clin. Invest. 84:640-646 (1989)). PDGFs include: PDGF; platelet derived angiogenesis factor (PDAF); TGF-.beta.; and PF4, which is a chemoattractant for neutrophils (Knighton et al., in Growth Factors and Other Aspects of Wound Healing: Biological and Clinical Implications, Alan R. Liss, Inc., New York, N.Y., pp. 319-329 (1988)). PDGF is a mitogen, chemoattractant and a stimulator of protein synthesis in cells of mesenchymal origin, including fibroblasts and smooth muscle cells. PDGF is also a nonmitogenic chemoattractant for endothelial cells (see, for example, Adelmann-Grill et al., Eur. J. Cell Biol. 51:322-326 (1990)).
[0080] IGF-1 acts in combination with PDGF to promote mitogenesis and protein synthesis in mesenchymal cells in culture. Application of either PDGF or IGF-1 alone to skin wounds does not enhance healing, but application of both factors together appears to promote connective tissue and epithelial tissue growth (Lynch et al., Proc. Natl. Acad. Sci. 76:1279-1283 (1987)).
[0081] TGF-.beta. is a chemoattractant for macrophages and monocytes. Depending upon the presence or absence of other growth factors, TGF-.beta. may stimulate or inhibit the growth of many cell types.
[0082] Other growth factors, such as EGF, TGF-.alpha., the HBGFs and osteogenin are also important in wound healing. Topical application of EGF accelerates the rate of healing of partial thickness wounds in humans (Schultz et al., Science 235:350-352 (1987)). Osteogenin, which has been purified from demineralized bone, appears to promote bone growth (see, e.g., Luyten et al., J. Biol. Chem. 264:13377 (1989)). In addition, platelet-derived wound healing formula, a platelet extract which is in the form of a salve or ointment for topical application, has been described (see, e.g., Knighton et al., Ann. Surg. 204:322-330 (1986)).
[0083] The heparin binding growth factors (HBGFs), including the fibroblast growth factors (FGFs), which include acidic HBGF (aHBGF also known as HBFG-1 or FGF-1) and basic HBGF (bHBGF also known as HBGF-2 or FGF-2), are potent mitogens for cells of mesodermal and neuroectodermal lineages, including endothelial cells (see, e.g., Burgess et al., Ann. Rev. Biochem. 58:575-606 (1989)). In addition, HBGF-1 is chemotactic for endothelial cells and astroglial cells. Both HBGF-1 and HBGF-2 bind to heparin, which protects them from proteolytic degradation. The array of biological activities exhibited by the HBGFs suggests that they play an important role in wound healing.
[0084] Basic fibroblast growth factor (FGF-2) is a potent stimulator of angiogenesis and the migration and proliferation of fibroblasts (see, for example, Gospodarowicz et al., Mol. Cell. Endocinol. 46:187-204 (1986) and Gospodarowicz et al., Endo. Rev. 8:95-114 (1985)). Acidic fibroblast growth factor (FGF-1) has been shown to be a potent angiogenic factor for endothelial cells (Burgess et al., supra, 1989). Other FGF's may be chemotactic for fibroblasts. Growth factors are, therefore, potentially useful for specifically promoting wound healing and tissue repair.
[0085] “HBGF-1,” which is also known to those of skill in the art by alternative names, such as endothelial cell growth factor (ECGF) and FGF-1, as used herein, refers to any biologically active form of HBGF-1, including HBGF-1.beta., which is the precursor of HBGF-1.alpha. and other truncated forms, such as FGF. U.S. Pat. No. 4,868,113 to Jaye et al., herein incorporated by reference, sets forth the amino acid sequences of each form of HBGF. HBGF-1 thus includes any biologically active peptide, including precursors, truncated or other modified forms, or mutants thereof that exhibit the biological activities, or a subset thereof, of HBGF-1.
[0086] Other growth factors may also be known to those of skill in the art by alternative nomenclature. Accordingly, reference herein to a particular growth factor by one name also includes any other names by which the factor is known to those of skill in the art and also includes any biologically active derivatives or precursors, truncated mutant, or otherwise modified forms thereof.
[0087] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs. Although any methods and materials similar or equivalent to those described can be used in the practice or testing of the present invention, the preferred methods and materials are now described. All publications and patent documents referenced in the present invention are incorporated herein by reference.
[0088] While the principles of the invention have been made clear in illustrative embodiments, there will be immediately obvious to those skilled in the art many modifications of structure, arrangement, proportions, the elements, materials, and components used in the practice of the invention, and otherwise, which are particularly adapted to specific environments and operative requirements without departing from those principles. The appended claims are intended to cover and embrace any and all such modifications, with the limits only of the true purview, spirit and scope of the invention. | A method and apparatus for treatment of skin or other tissue, using a source of thermal, electromagnetic radiation, electrical current, ultrasonic, mechanical or other type of energy, to cause minimally-invasive thermally-mediated effects in skin or other tissue which stimulates a wound-healing response, in conjunction with topical agents or other wound healing compositions, for application on the skin or other tissue which accelerate collagenesis, such as in response to wound healing. The dosage and time period of application of the compositions are adjusted to prevent external or surface tissue damage. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a division of application Ser. No. 09/731,108, filed on Dec. 6, 2000, which claims priority to Provisional Application Serial No. 60/169,413, filed on Dec. 7, 1999, Provisional Application Serial No. 60/229,548, filed on Sep. 5, 2000, and Provisional Application No. 60/229,549, filed on Sep. 5, 2000, the contents of which are hereby incorporated by reference.
BACKGROUND OF INVENTION
[0002] The present invention relates generally to syringes for use with injectors and, more particularly, to syringes, syringe tubing and fluid transfer systems having features that improve the ease of use and efficiency of loading fluid in and ejecting fluid from the syringes.
[0003] A number of injector-actuated syringes and powered injectors for use in medical procedures such as angiography, computed tomography, ultrasound and MRI have been developed. For example, U.S. patent No. discloses an apparatus for injecting fluid into the vascular system of a human being or an animal. Likewise, U.S. patent No. discloses an angiographic injector and syringe wherein the drive member of the injector can be connected to, or disconnected from, the syringe plunger at any point along the travel path of the plunger via a releasable mechanism requiring rotation of the syringe plunger relative to the piston. A front-loading syringe and injector system is disclosed in U.S. patent No. the disclosure of which is hereby incorporated by reference. The syringes disclosed in U.S. patent No. can be securely front-loaded directly and accurately on the injector or on a pressure jacket attached to the injector, thereby facilitating the loading-unloading operation as compared to prior systems.
[0004] To load syringes with contrast fluid, a user typically connects a fill tube to the front nozzle or discharge outlet of the syringe and places the other end of the tube in a bottle or bag of contrast medium or other fluid. The plunger of the syringe is retracted (usually by means of the injector piston) to aspirate the contrast into the syringe until the desired amount is loaded into the syringe. After the syringe is filled, the fill tube is then typically discarded. Often, contrast or other fluid contained in the fill tube may drip therefrom onto the floor or the injector.
[0005] After the syringe is filled with fluid, a connector tube is connected to the discharge outlet of the syringe and the connecting tube is primed (typically by advancing the plunger in the syringe) to eject air from the syringe and the connector tube (i.e., to prevent air from being injected into the patient). While this technique is entirely effective in purging air from the tubing connected to the syringe, it is undesirable to have liquids dispensed from the end of the tube. Often, the liquids dispensed from the end of the tube foul the exterior surface of the tubing or fall onto the floor. When dealing with contrast media, this is particularly undesirable because the media is very sticky and has a tendency to migrate to whatever surface the operator touches after purging the tube.
[0006] When the patient is ready for the injection, the patient end of the connector tube is connected to, for example, a catheter, in a patient. During the time period between priming the connector tube and connecting the patient end of the connector tube to the patient, the patient end of the connector tube should be maintained in a sterile condition.
[0007] A significant amount of time and attention is required to properly load syringes with fluid and to connect and prime the connector tube. Consequently, it is very desirable to develop a new syringe or to improve existing syringes to reduce operator time and involvement in loading the syringe with fluid and/or in priming and connecting the connector tubing, while also minimizing or eliminating discharge of contrast medium or other fluid from the syringe or tubing associated with the syringe.
SUMMARY OF INVENTION
[0008] The present invention provides syringes, syringe tubing and a fluid transfer system that reduces the amount of time and vigilance necessary to load the syringe with fluid, such as contrast fluid, to connect the syringe to a patient and to prime the syringe and connector tube assembly. In addition, the present invention provides a purge tube that is designed to minimize leakage of contrast medium or other fluid therefrom. Further, the present invention provides a syringe and connector tube assembly operable to maintain the sterility of the connector tube for subsequent connection to a patient.
[0009] In a first aspect, a syringe includes a body and a plunger disposed therein. The body includes a nozzle formed therein and a latch connected thereto or integrally formed thereon for holding a second end of a fill tube. The first end of the fill tube is preferably pre-connected to the nozzle. A plastic or other sheath is removably disposed around the fill tube between the first and second ends to maintain the fill tube in a clean and/or sterile condition prior to use for filling/loading the syringe with contrast.
[0010] In addition, the diameter of the syringe nozzle may be enlarged to provide for increased volumetric fluid flow (and thereby faster fluid filling/loading) into the syringe. Preferably, the internal diameter of the syringe may be increased from 0.1 inches to approximately 0.2 to 0.25 inches. The enlarged syringe nozzle may also decrease the formation of air bubbles, which typically occurs during syringe filling, thereby resulting in less air needing to be expelled from the syringe and the connector tubing prior to injection and decreased risk of an inadvertent air injection into a patient.
[0011] In a preferred embodiment, the syringe is packaged with the first end of the fill tube pre-connected to the nozzle and the second end held in the latch. The sheath preferably covers the fill tube. After the syringe is removed from its packaging, the second end of the fill tube is removed from the latch and the sheath is removed from the fill tube and discarded. The second end of the fill tube is then placed in a contrast or other fluid container. The plunger of the syringe is retracted to fill the syringe with the fluid in the container. After a sufficient amount of the fluid is aspirated into the syringe, the fill tube may then be disconnected from the syringe and, preferably, discarded.
[0012] In a second aspect, a syringe includes a body and a plunger disposed therein. The body includes a nozzle formed therein and at least one hub member connected thereto or integrally formed thereon for holding an end of a connector tube. In a preferred embodiment, the at least one hub member comprises two hub members disposed on the syringe body. The connector tube includes two ends, each end being connected to a respective hub member to retain the connector tube in contact with the syringe. Preferably, the syringe and the connector tube are packaged in a pre-connected condition for ease of use by the customer.
[0013] After the syringe is filled with fluid and the fill tube is disconnected from the discharge outlet or nozzle of the syringe, one end of the connector tube is removed from a hub member and connected to the nozzle of the syringe. The second end of the connector tube is removed from the other hub member and held, preferably over a refuse or other container (i.e., to collect any fluid ejected from the connector tube during the priming operation), while the syringe and connector tube is primed to remove air therefrom. After the priming operation is completed, the second end of the connector tube is replaced on the hub member on the syringe to maintain it in a sterile condition and/or an “out of the way” location until the second or patient end of the connector tube is connected to the patient.
[0014] Further, the connector tube may include one or more tethered caps to prevent the caps from being dropped on the floor or misplaced. The caps are used to close the open ends of the connector tube to, for example, prevent dust or other contaminants from entering the connector tube. After the syringe is filled and/or primed, a cap may be placed on the open, patient end of the connector tube to maintain sterility. In a preferred embodiment, the caps are tethered to the connector tube by a plastic or other member connected between each of the caps and the connector tube.
[0015] In a third aspect, a fluid transfer system includes a syringe, a fluid container and a transfer device for transferring fluid, such as contrast, from the container to the syringe to fill same. In a preferred embodiment, the transfer device includes a spike for puncturing the seal of the fluid container, a container holder for holding the fluid container on the spike, a valve for allowing fluid to enter the syringe and a syringe support member for aligning the syringe nozzle with the valve.
[0016] After the syringe is mounted on an injector, the spike of the transfer device is used to pierce the seal of the fluid container. The syringe support member of the transfer device is then placed over the nozzle of the syringe. The luer tip of the syringe nozzle engages the valve of the transfer device, thereby allowing the contents of the fluid container to flow into the syringe. To aspirate the contents of the fluid container into the syringe, the piston of the injector retracts the plunger of the syringe.
[0017] The container holder functions to maintain the fluid container in contact with the spike and the fluid transfer device as the fluid is transferred from the fluid container to the syringe. In addition, the syringe support member maintains the nozzle of the syringe aligned and engaged with the valve, which is preferably a check valve. In a preferred embodiment, the transfer system is disposable.
[0018] In a fourth aspect, a syringe includes a body and a plunger disposed therein. The body includes a nozzle formed therein. Flexible inlet tubing may be pre-connected or permanently connected to the nozzle of the syringe (or provided separately) to facilitate filling of the syringe prior to a medical procedure. The flexible tubing may remain attached to the nozzle of the syringe after filling thereof to reduce waste and the opportunity for contrast or other fluid from dripping from the syringe nozzle or the inlet tubing.
[0019] In a fifth aspect, the present invention provides a purge tube that can be connected to the end of a connector tube that delivers contrast media or other fluid to a patient. The purge tube may minimize or eliminate the discharge of contrast media from the end of the connector tube that delivers the media to the patient when the syringe and connector tube assembly is purged. In a preferred embodiment, the purge tube may collect any discharged liquid from the end of the connector tube that delivers the contrast media to the patient. The purge tube may then be removed from the connector tube and discarded to minimize or eliminate contamination of other surfaces by the liquid captured thereby.
[0020] Other aspects of the invention and their attendant advantages will be discerned from the following detailed description when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF DRAWINGS
[0021] Various embodiments of the present invention will be described below, which reference to the following drawings, in which:
[0022] [0022]FIG. 1 is a perspective view of an embodiment of the syringe of the present invention in a first orientation;
[0023] [0023]FIG. 2 is a partially exploded, perspective view of the syringe of FIG. 1 in a second orientation;
[0024] [0024]FIG. 3 is a perspective view of a connector tube with tethered caps for the ends thereof;
[0025] [0025]FIG. 4 is an exploded, perspective view of a preferred embodiment of the fluid transfer system of the present invention;
[0026] [0026]FIG. 5 is an isometric illustration of a syringe and flexible inlet tubing of the present invention;
[0027] [0027]FIG. 6 is an isometric illustration of an alternate embodiment of the flexible tubing illustrated in FIG. 5;
[0028] [0028]FIG. 7 is an isometric view of a purging tube of the present invention shown connected to a syringe;
[0029] [0029]FIG. 8 is an enlarged view of the purging tube shown in FIG. 7;
[0030] [0030]FIG. 9 is an isometric, exploded view of the purging tube shown in FIGS. 7 and 8; and
[0031] [0031]FIG. 10 is an isometric view of a syringe and the purging tube of the present invention.
DETAILED DESCRIPTION
[0032] As best shown in FIG. 1, a syringe 10 includes a body portion 12 and a plunger (not shown) movably disposed therein. The body portion 12 defines a nozzle or discharge outlet 16 at the front end thereof for discharging fluid contained within the syringe 10 to a patient and a latch or retention member 24 preferably disposed on a rearward end thereof.
[0033] The body portion 12 further includes at least two mounting flanges 17 and a sealing flange 19 for securely mounting the syringe on the front of an injector (not shown), as disclosed in U.S. Pat. No. 5,383,858, the contents of which are hereby incorporated by reference.
[0034] A fill tube 18 includes a first end 20 removably connected to the nozzle 16 of the syringe 10 and a second end 22 removably connected to the latch 24 on the body 12 of the syringe. A sheath 26 , which may be formed of plastic or other suitable material, covers the fill tube 18 to maintain the fill tube in a clean or sterile condition.
[0035] The syringe 10 is preferably packaged in a container (not shown) with the first end 20 of the fill tube 18 pre-connected to the luer tip (not shown) of the nozzle 16 and the second end 22 pre-connected to the latch 24 . In that manner, the operator does not have to connect the fill tube 18 to the syringe 10 before filling the syringe with fluid, which is convenient and saves operator time.
[0036] In use, after the syringe 10 is removed from its container, the second end 22 of the fill tube 18 is disconnected from the latch 24 and the sheath 26 is removed from the fill tube 18 (via the free second end 22 ). The second end 22 of the fill tube 18 may then be placed in a fluid container (not shown), such as a contrast container, to fill/load the syringe 10 with fluid. The fluid is aspirated into the syringe 10 by retracting the plunger within the syringe 10 , preferably by means of the injector piston (not shown). After the syringe 10 is filled, the first end 20 of the fill tube 18 can be removed from the nozzle 16 of the syringe 10 , and the fill tube 18 discarded.
[0037] In addition, as best shown in FIGS. 2 and 3, a connector tube 28 may be pre-connected to the syringe 10 . The connector tube 28 includes a first end 30 for connection to the nozzle 16 of the syringe 10 and a second or patient end 32 for connection to a patient (not shown). The syringe preferably includes two hub members 34 connected to or formed on the body portion 12 of the syringe. The ends 30 , 32 of the connector tube 28 are removably connected to a respective hub member 34 on the syringe 10 .
[0038] In use, the syringe 10 is preferably packaged with the ends 30 , 32 of the connector tube 28 connected to the hub members 34 on the syringe 10 . After the syringe is filled with fluid, the first end 30 of the connector tube 28 is connected to the nozzle 16 of the syringe 10 . The syringe 10 and the connector tube 28 are then primed to remove air therefrom by advancing the plunger within the syringe 10 . As a result, the air contained within the syringe 10 , along with possibly a small amount of fluid, 10 is ejected from the syringe 10 and the second end 32 of the connector tube 28 .
[0039] After the connector tube 28 is primed, the second end 32 of the tube 28 is reconnected to a hub member 34 until the operator is ready to connect the second end 32 to the patient. Alternately, the second end 32 may be connected to or draped over the latch 24 on the syringe 10 . By mounting the second end 32 of the connector tube 28 on the hub member 34 or the latch 24 , the second end 22 is kept clean and/or sterile and is placed in an “out of the way” location. Further, by effectively closing the open, second end 32 of the connector tube 28 with a hub member 34 , fluid is prevented from leaking from the connector tube 28 onto the floor or elsewhere.
[0040] Moreover, after the injection procedure is completed, the second end 32 of the connector tube 28 may be removed from the patient and reconnected to a hub member 34 to prevent fluid spillage. After the syringe 10 is removed from the injector, the syringe 10 and connector tube 28 can be disposed of as a unit.
[0041] As shown in FIG. 3, the connector tube 28 may also include tethered caps 36 for each end 30 , 32 thereof. The caps 36 may be used to close the open ends 30 , 32 of the connector tube 28 to prevent dust and other contaminants from contaminating the connector tube 28 and to prevent fluid from leaking therefrom. For example, after the connector tube 28 has been attached to the syringe 10 and primed to remove air therefrom, a cap 36 may be placed over the open, patient end 32 of the connector tube 287 to maintain sterility prior to injection.
[0042] In a preferred embodiment, the caps 36 are tethered to the connector tube 28 by means of tethers 38 disposed between the connector tube 28 and the caps 36 . The tethers 38 may be formed of plastic or any other suitable material.
[0043] As shown in FIG. 4, a fluid transfer system 40 includes a syringe 42 , a fluid container 44 and a transfer device 46 for transferring fluid, such as contrast, from the container 44 to the syringe 42 to fill it. (The syringe 42 may contain the same features as discussed above with respect to the syringe 10 shown in FIGS. 1 and 2.) In a preferred embodiment, the transfer device 46 includes a conventional spike 48 for puncturing the seal of the fluid container 44 , a container holder or cup 50 for holding the fluid container 44 on the spike 48 , a valve (not shown), such as a check valve, for allowing fluid to enter the syringe 42 and a syringe support member or sleeve 54 for holding the syringe 42 in relationship to the transfer device 46 .
[0044] After the syringe 42 is mounted on an injector (not shown), the plunger (not shown) is advanced to expel air from the syringe 42 . The syringe 42 is then ready to be filled with fluid. The transfer device 46 may then be inserted onto the fluid container 44 such that the spike 48 pierces the seal of the fluid container 44 . The syringe support member 54 of the transfer device 46 may then be placed over the nozzle of the syringe 42 . Within the support member 54 , the luer tip 56 of the syringe 42 engages and actuates the valve to open a passage for fluid to flow from the container 44 to the syringe 42 . To aspirate the contents of the fluid container 44 into the syringe 42 , the injector piston (not shown) retracts the plunger (not shown) of the syringe 42 .
[0045] In a preferred embodiment, when the luer tip 56 of the syringe 42 opens the valve, fluid will not substantially flow from the container 44 until the plunger is retracted to create a suction to aspirate fluid into the syringe 42 . This design prevents fluid from inadvertently spilling from the container 44 . Further, the container holder 50 and the syringe support member 54 are designed to impart rigidity to the system and to maintain the syringe 42 and the container 44 in contact with the transfer device 46 . In a preferred embodiment, the transfer system 46 is disposable.
[0046] A syringe and an inlet tube of the present invention are shown in FIGS. 5 and 6. The syringe 100 includes a cylindrical body 112 and a frusto-conical forward end 114 that transitions into a discharge end 116 . A flexible inlet tube 118 is connected to the discharge end 116 . Preferably, the flexible tube 118 contains a flexible (or corrugated) section 120 disposed between two smooth (or non-corrugated) sections 122 , 124 . Flexible tubing 118 may be composed of any suitable polymeric material so long as the material is flexible, durable, and suitable for medical use.
[0047] While flexible tubing 118 is illustrated with two smooth sections 122 , 124 connected to one another by a corrugated section 120 , other alternative constructions are contemplated within the scope of the present invention. For example, the flexible tube may include one corrugated section and one smooth (non-corrugated) section. In still another embodiment, the flexible tube may not include any corrugated sections at all, but instead, may incorporate some other alternative flexible section or sections to accomplish the same objective.
[0048] Flexible tubing 118 may be releasably connected to discharge or dispensing end 116 of syringe 110 or it may be permanently attached thereto. Similarly, flexible tubing 118 may be supplied with syringe 110 or it may be supplied separately and used with syringe 110 . As can be readily appreciated, the flexible nature of inlet tube 118 allows it to be easily maneuvered for use with fluid bags or bottles to fill the syringe 110 .
[0049] At the end of flexible tubing 118 opposite to the end connected to dispensing end 116 of syringe 110 , a luer lock 126 is provided. After filling syringe 110 , once filler bag or bottle has been removed from flexible tubing 118 , a low-pressure connector tubing (“LPCT”) may be connected directly to luer lock 126 for connection to the patient.
[0050] [0050]FIG. 6 illustrates another embodiment of the present invention, which is specifically directed at the filling of syringe 110 from a bottle of contrast medium. A tube extension 128 is illustrated that releasably connects to luer lock 126 . The extension tubing 128 is inserted into the bottle of contrast media for filling syringe 110 . After syringe 110 is filled, extension tubing 128 is removed from the bottle, disconnected from luer lock 126 , and discarded. After purging, syringe 110 may then be connected to the patient.
[0051] The embodiment shown in FIG. 6 facilitates filling of syringe 110 . In addition, tubing extension 128 , which is usually covered with contrast media after syringe 110 is filled, may be discarded to reduce contamination of equipment with contrast media that may remain thereon.
[0052] A syringe and purging tube of the present invention is shown in FIGS. 7 - 10 . FIG. 7 illustrates a syringe 210 with a discharge end 212 . Discharge end 212 is usually provided with a luer lock so that a tube 214 , such as a low-pressure connector tubing (or “LPCT”), may be connected thereto.
[0053] In the embodiment illustrated, connector tube 124 includes a luer lock 216 at a distal end. A purging tube 218 is removably connected to the luer lock 216 of the connector tube 214 . Purging tube 218 , which is shown in detail in FIG. 8, has a vented cap 220 at the distal end thereof. As illustrated in FIG. 9, between purging tube 218 and vented cap 220 are disposed two additional elements, a flow preventor 222 and a seal (or spacer) 224 . Seal 224 is disposed between purging tube 218 and flow preventor 222 . Flow preventor 222 may be any suitable material (including paper) that inhibits the flow of contrast media, but allows air to pass therethrough and out of the end of purging tube 218 . The vented cap 220 , in a preferred embodiment, provides a support structure for the flow preventor 222 and allows air to pass therethrough from the flow preventor 222 to the atmosphere. In the preferred embodiment, flow preventor 222 is made of Goretex®, which is the trade name of a vapor-breathable fabric made by W. L. Gore and Associates.
[0054] After a syringe 210 is filled with a fluid, such as a contrast media, the air remaining in the LPCT 214 and the syringe 210 should be purged (e.g., by advancing the syringe plunger) before the LPCT 214 is connected to a patient. During purging, some contrast media will often be forced out of the distal end of the LPCT 214 . Purging tube 218 is provided with a sufficiently large interior volume to collect that discharged media. In a preferred embodiment, the purging tube 218 is adapted to contain approximately 3 ml of fluid. In addition, the purge tube 218 is preferably pre-connected to the distal end of the LPCT 214 . The vented cap 220 allows air to be discharged from the purge tube 218 and the flow preventor 222 inhibits leakage of contrast media from the distal end of purging tube 218 during the purging operation. As can be appreciated, while flow preventor 22 does inhibit the flow of fluid therethrough, it will not prevent fluid flow if a sufficient volume of fluid is discharged into the purge tube 218 . Therefore, during the purging operation, an operator should be careful not to discharge into the purge tube 218 more fluid than the fluid volume capacity of the purge tube 218 .
[0055] During the purging operation, the distal end of the purge tube 218 is preferably held in an elevated position (i.e., opposite from the ground) to further prevent fluid from being discharged from the purge tube 218 . However, the purging operation could be conducted with the distal end of the purge tube 218 held in any orientation. After the purging operation is completed, the purge tube 218 contains the fluid discharged from the syringe 210 and the connector tubing 214 . To prevent the discharged fluid from leaking out of the proximal end of the purge tube 218 (i.e., the end connected to the distal end of the LPCT 214 ), the proximal end of the purge tube 218 is preferably elevated prior to or immediately after being disconnected from the connector tube 214 . Thereafter, the purge tube 218 is preferably discarded and the connector tube 214 is connected to a catheter in a patient for an injection procedure.
[0056] Purging tube 218 offers at least one further advantage. With purging tube 218 , it is possible to design an injector that has an automatic purge feature. See, for example, the auto prime feature described in PCT International Application No. PCT/US00/31991, filed on Nov. 21, 2000, the contents of which are hereby incorporated by reference. Specifically, the injector (not shown) may have a button that the practitioner may push to clear air from syringe 210 and the LPCT 214 . Upon actuation of the auto purge feature, the injector would advance the plunger in the syringe by a predetermined amount. By providing purging tube 218 with a sufficient interior volume, the auto purge feature should not exceed the interior volume of the purging tube 218 .
[0057] [0057]FIG. 10 illustrates the purging tube 218 of the present invention in use with a syringe 230 having a discharge end 232 . Syringe 230 may be of the type typically used for the injection of contrast media into a patient for vascular imaging, for example. While syringe 230 differs from syringe 210 shown in FIG. 7, in all other respects the use and function of purging tube 218 is the same as described above.
[0058] In an alternate embodiment, the vented cap 220 and the flow preventor 222 may be positioned at a location between the proximal and distal ends of the purge tube 218 . When fluid is discharged into the purge tube 218 past the vented cap 220 and the flow preventor 222 (i.e., to the distal side thereof during the purging operation, the fluid will cooperate with the flow preventor 222 to prevent the fluid from leaking from the proximal and distal ends of the purge tube 218 after the purge tube 218 is disconnected from the connector tube 214 . This alternate design may reduce the need for the operator to elevate the proximal end of the purge tube 218 prior to or immediately after it is disconnected from the connector tube 218 , as discussed above with respect to the preferred embodiment.
[0059] In yet another embodiment, the vented cap 220 and flow preventor 222 may be replaced with a one-way check valve (not shown) that is biased in a closed position. During the purging operation, the check valve would be forced open to allow air to pass therethrough. After the purging operation is completed, the check valve will close and, when the purge tube 218 is disconnected from the LPCT 214 , operate to prevent fluid from leaking from the proximal and distal ends of the purge tube 218 .
[0060] Furthermore, while one aspect of the present invention has been described above in terms of a purging “tube,” it should be appreciated that the term “tube” is not limiting and should be construed to include all suitable types of structures and containers for retaining the discharged fluid from the syringe and the LPCT 214 .
[0061] Although the present invention has been described in detail in connection with the above examples and embodiments, it is to be understood that such detail is solely for that purpose and that those skilled in the art can make variations without departing from the invention. The invention is not limited to the disclosed embodiments, but may be practiced within the full scope of the appended claims. | A syringe includes a body and a plunger disposed therein. The body includes a nozzle formed therein and at least one hub member connected thereto or integrally formed thereon for holding an end of a connector tube. The connector tube includes two ends, each end preferably being connected to a respective hub member to retain the connector tube in contact with the syringe. Preferably, the syringe and the connector tube are packaged in a pre-connected condition for ease of use by the customer. Furthermore, flexible inlet tubing for connection to a syringe for filling the syringe with contrast media, for example, is described. The inlet tubing permits filling of the syringe from either a bag or a bottle and may remain attached to the syringe so that it forms at least a part of the connection to the patient. In addition, an apparatus for facilitating the purge of air from a connector tube that will ultimately be connected between a syringe and a patient is described. The apparatus includes a purging tube connected to the distal end of the connector tubing from the syringe. The purging tube includes a venting cap at its distal end. A flow inhibitor is positioned under the venting cap to cooperate with the venting cap by discouraging the discharge of fluid from the distal end of the purging tube while permitting the discharge of air therefrom. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of provisional application Ser. No. 60/771,535, filed Feb. 8, 2006, the entire contents of which are incorporated herein by reference.
BACKGROUND
The invention relates generally to an enhanced performance connector and in particular, to a connector including a plug and outlet designed for enhanced performance.
Improvements in telecommunications systems have resulted in the ability to transmit voice and/or data signals along transmission lines at increasingly higher frequencies. Several industry standards that specify multiple performance levels of twisted-pair cabling components have been established. The primary references, considered by many to be the international benchmarks for commercially based telecommunications components and installations, are standards ANSI/TIA/EIA-568-A (/568) Commercial Building Telecommunications Cabling Standard and ISO/IEC 11801 (/11801), generic cabling for customer premises. For example, Category 3, 4 and 5 cable and connecting hardware are specified in both /568 and /11801, as well as other national and regional specifications. In these specifications, transmission requirements for Category 3 components are specified up to 16 MHz. Transmission requirements for Category 4 components are specified up to 20 MHz. Transmission requirements for Category 5 components are specified up to 100 MHz. The above referenced transmission requirements also specify limits on near-end crosstalk (NEXT).
Often, telecommunications connectors are organized in sets of pairs, typically made up of a tip and ring connector. As telecommunications connectors are reduced in size, adjacent pairs are placed closer to each other creating crosstalk between adjacent pairs. To comply with the near-end crosstalk requirements, a variety of techniques are used in the art.
Compensation for the modular jacks and plugs has been added using external elements such as a PCB, flex circuits, discreet components (i.e. resistors, capacitors). These previous methods add cost and complexity. As the bandwidth requirements increase due to higher signaling rates, such as 10GBASE-T Ethernet and beyond, components need to be improved.
While there exist plugs and outlets designed to reduce crosstalk and enhance performance, it is understood in the art that improved plugs and outlets are needed to meet increasing transmission rates.
SUMMARY
An embodiment of the invention is a telecommunications outlet including a contact carrier and a plurality of contacts supported on the contact carrier, the contacts corresponding to tip and ring pairs, at least one of the contacts having a characteristic to improve signal transmission performance by providing internal compensation to balance signals by controlling resistive, inductive or capacitive characteristics along the contacts.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of an outlet in embodiments of the invention.
FIG. 2 is a perspective view of a contact carrier of FIG. 1 .
FIG. 3 is a side view of the contact carrier of FIG. 2 .
FIG. 4 is a front view of an outlet in alternate embodiments of the invention.
FIG. 5 is a perspective view of a contact carrier of FIG. 4 .
FIG. 6 is a side view of the contact carrier of FIG. 5 .
FIG. 7 is a front view of an outlet in alternate embodiments of the invention.
FIG. 8 is a bottom view of the outlet of FIG. 7 .
FIG. 9 illustrates contacts within the outlet of FIG. 7 .
FIG. 10 is a perspective view of an outlet in alternate embodiments of the invention.
FIG. 11 is a cross-sectional view of a plug mating with the outlet of FIG. 10 .
FIG. 12 is a perspective view of the contact carrier of FIG. 10 on a circuit board.
FIG. 13 is a perspective view a contact carrier in alternate embodiments.
FIG. 14 is a perspective, partial cut-away view of a plug in embodiments of the invention.
FIG. 15 is a top view of the plug of FIG. 13 .
DETAILED DESCRIPTION
FIG. 1 is a front view of an outlet 100 in embodiments of the invention. As known in the art, the outlet includes eight contacts 102 . It is understood that the number of contacts may vary depending on application, and embodiments of the invention are not limited to eight contacts. As is known in the art, contacts are referred to as being in eight positions 1-8, from one side of the outlet to the other. The contacts may be arranged in tip and ring pairs as is known in the art with, contacts 1/2, 3/6, 4/5 and 7/8 defining tip and ring pairs. Embodiments of the invention are described with reference to contacts in different positions.
FIG. 2 is a perspective view of a contact carrier 104 of FIG. 1 , depicting the first contact as 102 1 . In this embodiment crosstalk is reduced by altering features of the contacts 102 . One feature is the length of the contacts. In FIG. 2 , contacts in positions 3 and 6 are shorter than the other contacts. Thus, contacts 3 and 6 do not extend as far in the mating region 106 above the top surface of contact carrier 104 where contacts from a plug make electrical contact with contacts 102 . Another feature is the angle of the contact with respect to an axis X parallel to the top surface of the contact carrier. Contacts in positions 4, 6 and 8 are at a first angle (e.g., 20.5 degrees) with reference to axis X. Other contacts in positions 2, 5 and 7 are at a second angle (e.g., 12 degrees) with reference to axis X. Another feature is the inclusion of a bend in the contact, such that the angle of the contact with reference to axis X decreases at the bend. As shown in FIGS. 2 and 3 , contact in position 1 has a bend towards axis X.
This arrangement of the contacts improves signal transmission performance by providing internal compensation to balance signals by adjusting the contacts to maximize resistive, inductive, capacitive characteristics (including signal phase delay) along contacts 102 . For example, adjusting the length, adding bends, adjusting the spacing of the contacts is performed to compensate for crosstalk within the outlet. Further, the cross sectional size of the contacts, the cross sectional shape of the contacts and/or the conductivity of the material used in one or more of the contacts may be varied to alter resistive, inductive, capacitive characteristics (including signal phase delay) of contacts 102 .
FIG. 4 is a front view of an outlet 200 in embodiments of the invention. As known in the art, the outlet includes eight contacts 202 . It is understood that the number of contacts may vary depending on application, and embodiments of the invention are not limited to eight contacts. As is known in the art, contacts are referred to as being in eight positions 1-8, from one side of the outlet to the other. The contacts may be arranged in tip and ring pairs as is known in the art with, contacts 1/2, 3/6, 4/5 and 7/8 defining tip and ring pairs.
Embodiments of the invention are described with reference to contacts in different positions. FIG. 5 is a perspective view of a contact carrier 204 of FIG. 4 , depicting the first contact as 202 1 . In this embodiment crosstalk is reduced by altering features of the contacts 202 . One feature is the length of the contacts. In FIG. 5 , contacts in positions 3 and 6 are shorter than the other contacts. Thus, contacts 3 and 6 do not extend as far in the mating region 206 above the top surface of contact carrier 104 where contacts from a plug make electrical contact with contacts 102 . Another feature is the angle of the contact with respect to an axis X parallel to the top surface of the contact carrier. As shown in FIG. 6 , contacts in positions 4, 6 and 8 are at a first angle (e.g., 20.5 degrees) with reference to axis X. Other contacts in positions 1, 2, 3, 5 and 7 are at a second angle (e.g., 12 degrees) with reference to axis X.
This arrangement of the contacts improves signal transmission performance by providing internal compensation to balance signals by adjusting the contacts to maximize resistive, inductive, capacitive characteristics (including signal phase delay) along contacts 202 . For example, adjusting the length, adding bends, adjusting the spacing of the contacts is performed to compensate for crosstalk within the outlet. Further, the cross sectional size of the contacts, the cross sectional shape of the contacts and/or the conductivity of the material used in one or more of the contacts may be varied to alter resistive, inductive, capacitive characteristics (including signal phase delay) of contacts 202 .
FIG. 7 is a front view of an outlet 300 in alternate embodiments of the invention. As known in the art, the outlet includes eight contacts 302 . It is understood that the number of contacts may vary depending on application, and embodiments of the invention are not limited to eight contacts. As is known in the art, contacts are referred to as being in eight positions 1-8, from one side of the outlet to the other. The contacts may be arranged in tip and ring pairs as is known in the art with, contacts 1/2, 3/6, 4/5 and 7/8 defining tip and ring pairs. Embodiments of the invention are described with reference to contacts in different positions.
FIG. 8 is a bottom view of the outlet of FIG. 7 . As shown in FIG. 8 , contacts in positions 4 and 5 are moved to be closer together along axis Y than other adjacent contacts. The axis Y is parallel to the side of the outlet 300 and extends parallel to the 8 contacts 302 . FIG. 9 illustrates contacts within the outlet of FIG. 7 . As shown in FIG. 9 , contacts 302 in positions 3 and 6 are moved back relative to the remaining contacts towards a rear wall 306 of outlet 300 . Further, contacts 302 in positions 3 and 6 are moved upwards relative to the remaining contacts towards a top wall 308 of the outlet 300 . The positioning of contacts 302 may be varied to alter resistive, inductive, capacitive characteristics (including signal phase delay) of contacts 302 . Further, the cross sectional size of the contacts, the cross sectional shape of the contacts and/or the conductivity of the material used in the contacts may be varied to alter resistive, inductive, capacitive characteristics (including signal phase delay) of contacts 202 .
FIG. 10 is a perspective view of an outlet 400 in embodiments of the invention. As known in the art, the outlet includes eight contacts 402 . It is understood that the number of contacts may vary depending on application, and embodiments of the invention are not limited to eight contacts. As is known in the art, contacts are referred to as being in eight positions 1-8, from one side of the outlet to the other. The contacts may be arranged in tip and ring pairs as is known in the art with, contacts 1/2, 3/6, 4/5 and 7/8 defining tip and ring pairs.
Embodiments of the invention are described with reference to contacts in different positions. As shown in FIG. 10 , all contacts 402 have a bend that directs the contact towards axis X ( FIG. 11 ). Contacts 402 in positions 4, 6 and 8 are have a higher angle with reference to axis X than contacts 402 in positions 1-3, 5 and 7 which have a smaller angle with reference to axis X. Axis X is parallel to the top surface of contact carrier 404 . FIG. 11 is a cross-sectional view of a plug 406 mating with outlet 400 . The bends in the contacts 402 permit the contacts 402 to maintain consistent physical and electrical contact with contacts 408 in plug 406 in mating region 426 above top surface of the contact carrier 404 . The bends also provide a uniform displacement of the contacts 402 when plugs having different dimensions are mated with outlet 400 . Accordingly, in the mated state, the contacts 402 are in predicted positions regardless of the size of the plug 406 or insertion depth of the plug 406 into outlet 400 . This allows for control of crosstalk between contacts 402 as the location of the contacts in the mated state does not vary. FIG. 12 is a perspective view of the contact carrier 404 of FIG. 10 on a circuit board 410 .
This arrangement of the contacts improves signal transmission performance by providing internal compensation to balance signals by adjusting the contacts to maximize resistive, inductive, capacitive characteristics (including signal phase delay) along contacts 402 . For example, adjusting the length, adding bends, adjusting the spacing of the contacts is performed to compensate for crosstalk within the outlet. Further, the cross sectional size of the contacts, the cross sectional shape of the contacts and/or the conductivity of the material used in one or more of the contacts may be varied to alter resistive, inductive, capacitive characteristics (including signal phase delay) of contacts 402 .
FIG. 13 is a perspective view of an exemplary termination of wires to an outlet in embodiments of the invention. FIG. 13 depicts an exemplary connector housing 701 , patch cord 700 and twisted pair cable 707 . Cable 707 includes four twisted pairs of wires 708 . It is understood that embodiments of the invention may be used with cables having a different color code and the invention is not limited to cables having four twisted pairs of wires. The patch cord 700 includes a plug housing dimensioned to mate with existing modular outlets. The plug housing may be an RJ-45 type plug, but may have different configurations.
Connector 701 contains a substrate 703 which establishes an electrical connection between the jack assembly 702 and termination block 705 . Wire termination connections 704 (e.g., insulation displacement contacts) are positioned in the termination block 105 . The substrate 703 may be a printed circuit board, flexible circuit material, etc. having traces therein for establishing electrical connection between the jack assembly 702 contacts and termination block 705 termination connections 704 . Termination block 705 may be a S310 block available from The Siemon Company. Substrate 703 may include compensation elements for tuning electrical performance of the plug 100 (e.g., NEXT, FEXT). In alternate embodiments, the jack assembly contacts 702 and IDC connections 704 are part of a lead frame, eliminating the need for substrate 703 .
The jack assembly 702 includes a contact carrier with contacts 720 . The contacts 720 may use one or more of the geometries described above with reference to FIGS. 1-12 to improve signal transmission performance by providing internal compensation to balance signals by adjusting the contacts to maximize resistive, inductive, capacitive characteristics (including signal phase delay) along contacts 720 .
For example, adjusting the length, adding bends, adjusting the spacing of the contacts is performed to compensate for crosstalk within the outlet. Further, the cross sectional size of the contacts, the cross sectional shape of the contacts and/or the conductivity of the material used in one or more of the contacts may be varied to alter resistive, inductive, capacitive characteristics (including signal phase delay) of contacts 720 . The contacts 720 extend from the rear wall of the contact carrier rather than the bottom (as shown in FIGS. 1-12 ), but still may include similar features to improve signal transmission performance.
FIG. 14 is a perspective, partial cut-away view of a plug 500 in embodiments of the invention. Plug 500 includes a plug housing 501 and plug contacts 502 arranged in eight positions across the plug 500 . Contacts 502 include an insulation displacement portion 503 for making electrical contact with individual wires as known in the art. The plug contacts 502 engage contacts in the outlets discussed above with reference to FIGS. 1-13 . As shown in FIG. 14 , the contacts 502 include extension 504 . The extensions form increased surface area for the contacts and overlap in order to alter capacitive and/or inductive (e.g., reactive) interaction between contacts 502 . In FIG. 14 , contacts in positions 1, 3, 6 and 8 include extensions 504 to increase capacitive coupling between contacts 1 and 3 and contacts 6 and 8, respectively. It is understood that other contacts may include extensions and embodiments of the invention are not limited to FIG. 14 . FIG. 15 is a top view of the plug of FIG. 14 . In alternate embodiments, the contacts 502 include openings to alter capacitive and/or inductive (e.g., reactive) interaction between contacts 502 . The openings may be formed uniformly across all contacts 502 , or may be formed in a subset of contacts 502 .
The embodiments of the invention discussed above improve the transmission performance (both signal and noise characteristics) of the RJ45 jack and/or plug by adding internal compensation within the components. The various wire forms adjust the magnitude and phase of the signals within the jack and this compensation improves overall signal integrity of the component.
While preferred embodiments have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustration and not limitation. | A telecommunications outlet including a contact carrier and a plurality of contacts supported on the contact carrier, the contacts corresponding to tip and ring pairs, at least one of the contacts having a characteristic to improves signal transmission performance by providing internal compensation to balance signals by controlling resistive, inductive or capacitive characteristics along the contacts. | 7 |
REFERENCE TO EARLIER FILED APPLICATION
[0001] This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 61/323,608, filed Apr. 13, 2010, and titled “METHODS FOR PROVIDING ENHANCED RESVERATROL ACTIVITY USING 4-ACETOXY-RESVERATROL,” which is incorporated, in its entirety, by this reference.
FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] This invention was made with Government support under Grant No. GM057275, awarded by the National Institute of Health (NIGMS) and Grant No. NR12004-01811, awarded by the U.S. Dept. of Agriculture (USDA).
BACKGROUND
Technical Field
[0003] The present invention relates to methods of treating biological conditions involving sirtuin enzymes with ester analog compounds of resveratrol that activate sirtuin enzymes, and more particularly to medicinal and cosmetic uses of 4-acetoxy-resveratrol.
[0004] The sirtuins are a class of NAD + -dependent protein deacetylase enzymes that regulate a wide variety of cellular activities that promote cell survival and extend lifespan in response to environmental stress. Sirtuins exert their effect by removing acetyl groups from certain target proteins, including histones, transcription factors and cytosolic acetyl CoA synthetase, in the presence of oxidized nicotinamide adenine dinucleotide (NAD + ). For example, the yeast sirtuin enzyme Sir2 (silent information regulator 2), originally identified for its role in silencing transcription of DNA, has also been shown to promote cell survival in response to caloric restriction. Similarly, in C. elegans , the sirtuin enzyme SIR-2.1 has been shown to extend lifespan. In mammalian cells, the sirtuin enzyme SIRT1 (a homolog of the yeast Sir2 and C. elegans SIR-2.1 enzymes) deacetylates the tumor suppressor p53 to promote cell survival. Sirtuins therefore appear to be activated as part of a beneficial cellular response to stress, resulting in cell survival and extended lifespan. Activators of sirtuins may therefore be beneficial in effecting fundamental cellular processes that protect cells from stress and prevent or treat age-related diseases, and lengthen healthy life.
[0005] Resveratrol (3,5,4′-trihydroxy-trans-stilbene) is a polyphenol compound, known to be the most potent activator of sirtuins. As a stilbene phytoalexin, resveratrol continues to receive increasing attention for its role in mitigation of numerous and diverse human pathological processes including inflammation, atherosclerosis, and carcinogenesis. Resveratrol is known for its activity as an antioxidant, cyclooxygenase inhibitor, lipid modifier, platelet aggregation inhibitor and vasodilator, inhibitor of tumor initiation, promotion and progression, neuroprotector, and antiviral compound.
[0006] Resveratrol is an especially abundant component of red wines produced from grapes grown in cooler climates where plants are under stress from heavy disease pressure. Indeed, the consumption of red wine containing resveratrol is believed to be responsible for the surprisingly normal lifespan of the French, despite their heavy consumption of fatty foods that cause heart disease, a phenomenon referred to as the “French Paradox.” Resveratrol, however, is not an optimal sirtuin activator. Its practical use is also limited due to difficult isolation and stereo-selectively of extracts obtained from plant sources. More significantly, resveratrol is highly unstable due to its potential for oxidation, resulting in the formation of unstable radicals and quinones, and requiring its isolation be carried out from impure mixtures containing multiple components.
BRIEF SUMMARY
[0007] The present invention provides a resveratrol analog compound, 4-acetoxy-resveratrol (also sometimes referred to as 4′-acetoxy-resveratrol or 4AR), which shows significantly enhanced resveratrol activity.
[0008] 4AR has the following chemical formula:
[0000]
[0009] In some embodiments, methods for treating and preventing physiological and pathophysiological conditions mediated by (1) sirtuins, (2) estrogen and anti-estrogen hormone actions, and (3) chemical interventions important for male and female health, aging, anti-aging and age-related disorders are disclosed. This includes conditions and disorders such as obesity, weight control, diabetes, insulin-resistance, cardiovascular disease, atherosclerosis, bone loss or osteoporosis, Alzheimer's disease and neurodegeneration, skin disorders and skin cancer, prostate cancer and other forms of carcinogenesis and benign prostatic hyperplasia or BPH.
[0010] In some embodiments, the invention provides a method of enhancing resveratrol activity comprising administering a therapeutically effective amount of 4-acetoxy-resveratrol.
[0011] In some embodiments, the invention provides a method of treating or preventing conditions mediated by sirtuins, comprising administering a therapeutically effective amount of 4-acetoxy-resveratrol.
[0012] In some embodiments, the invention provides a method of treating or preventing conditions mediated by estrogen and anti-estrogen hormone actions comprising administering a therapeutically effective amount of 4-acetoxy-resveratrol.
[0013] In some embodiments, the invention provides a method of treating or preventing a skin condition comprising administering a therapeutically effective amount of 4-acetoxy-resveratrol.
[0014] In some embodiments, the invention provides a method wherein 4-acetoxy-resveratrol is administered in a topical cream, lotion, gel or other cosmetic formulation, optionally including another resveratrol ester analog or combination of resveratrol ester analogs in concentrations between 0.3% and 12%.
[0015] In some embodiments, the invention provides a method wherein 4-acetoxy-resveratrol is administered in a dermal patch delivery system, optionally including another resveratrol ester analog or combination of resveratrol ester analogs in a concentration between 1% and 30%.
[0016] In some embodiments, the invention provides a method, wherein 4-acetoxy-resveratrol is administered in an oral dosage, optionally including another resveratrol ester analog or combination of resveratrol ester analogs in an amount between 10 mg and 1600 mg.
[0017] In some embodiments, the invention provides a method wherein 4-acetoxy-resveratrol is administered by injection, optionally including another resveratrol ester analog or combination of resveratrol ester analogs in an amount between 5 mg and 1600 mg.
[0018] In some embodiments, the invention provides a method wherein 4-acetoxy resveratrol is administered in a food product, optionally including another resveratrol ester analog or combination of resveratrol ester analogs in a concentration between 0.1% and 10%. In some embodiments, the food product is selected from an energy bar, cereal, beverage, energy drink, dip, yogurt, gum, and candy.
FIGURE
[0019] FIG. 1 depicts histological slides of in vitro Human Dermal Tissue Model in gene array studies.
DETAILED DESCRIPTION
[0020] Resveratrol and its analogs, including 4AR, bind to multiple substrates and, consequently, have multiple biological functions. For example, 4AR functions as an antioxidant, a cyclooxygenase inhibitor, and a lipid modifier. They positively influence fatty acid synthesis, prevent inflammation, promote longevity in cells, extend the life span (anti-aging) of organisms, promote dermal molecules or components of skin (such as increasing collagen deposition in human fibroblasts and positively enhance many other dermal components such as elastin, elastase, matrix metalloproteinases, collagenases, glycoaminoglycans, and hyaluronic acid at the epidermal/dermal junction).
[0021] Additionally, 4AR can bind the abundant distribution of beta estrogen receptors in the keratinocytes of the epidermis and fibroblasts in the dermis that also have a positive influence on skin parameters and enhanced dermal health and act as an anti-aging factor in skin.
[0022] Preparation of 4AR
[0023] 4′-Acetoxy-Resveratrol (referred to herein as 4AR) can be synthesized in five steps beginning with resorcyclic acid, as described in PCT/US05/02229 (WO 2005/069998) which is hereby incorporated by reference in its entirety.
[0024] Compounds
[0025] The methods of the present invention use the compound 3,5-dihydroxy-4′-acetoxy stilbene (also referred to as 4′-acetoxy resveratrol, 4-acetoxy resveratrol, and 4AR). 4AR is capable of forming both pharmaceutical and cosmetically acceptable formulations.
[0026] Pharmaceutical Uses
[0027] The compositions disclosed herein can be prepared and administered in a wide variety of oral and parenteral dosage forms. Thus, the compositions can be administered by injection, that is, intravenously, intramuscularly, intracutaneously, subcutaneously, intraduodenally, or intraperitoneally. Also, the compositions can be administered by inhalation, for example, intranasally. Additionally, the compositions can be administered transdermally. It will be obvious to those skilled in the art that the following dosage and application forms may comprise as the active component, either 4-acetoxy resveratrol or a corresponding pharmaceutically or cosmetically acceptable salt of 4-acetoxy-resveratrol which has the following structure:
[0000]
[0000] In some embodiments, 4-acetoxy-resveratrol is in the cis configuration. In some embodiments, 4-acetoxy-resveratrol is in the trans configuration. In some embodiments, 4-acetoxy-resveratrol exists in both the cis and trans configurations.
[0028] As used herein, the term “resveratrol activity” includes biological activity which 4AR and/or resveratrol exhibits. For example, resveratrol activity includes biological processes involved in inflammation, atherosclerosis, carcinogenesis, or as an antioxidant, cyclooxygenase inhibitor, lipid modifier, platelet aggregation inhibitor and vasodilator, inhibitor of tumor initiation, promotion and progression, neuroprotector, and antiviral compound. Resveratrol activity also includes enhancing skin health and other conditions pertaining to aging, anti-aging, and age-related disorders.
[0029] For preparing pharmaceutical compositions from the compounds of the present invention, pharmaceutically acceptable carriers can be either solid or liquid. Solid form preparations include powders, tablets, pills, capsules, cachets, suppositories, and dispersible granules. A solid carrier can be one or more substances which may also act as diluents, flavoring agents, binders, preservatives, tablet disintegrating agents, or an encapsulating material.
[0030] In powders, the carrier is a finely divided solid which is in a mixture with the finely divided active component.
[0031] In tablets, the active component is mixed with the carrier having the necessary binding properties in suitable proportions and compacted in the shape and size desired.
[0032] The powders and tablets preferably contain from about five or about ten to about seventy percent of the active compound. Suitable carriers are magnesium carbonate, magnesium stearate, talc, sugar, lactose, pectin, dextrin, starch, gelatin, tragacanth, methylcellulose, sodium carboxymethylcellulose, a low melting wax, cocoa butter, and the like. The term “preparation” is intended to include the formulation of the active compound with encapsulating material as a carrier providing a capsule in which the active component with or without other carriers, is surrounded by a carrier, which is thus in association with it. Similarly, cachets and lozenges are included. Tablets, powders, capsules, pills, cachets, and lozenges can be used as solid dosage forms suitable for oral administration.
[0033] For preparing suppositories, a low melting wax, such as a mixture of fatty acid glycerides or cocoa butter, is first melted and the active component is dispersed homogeneously therein, as by stirring. The molten homogeneous mixture is then poured into conveniently sized molds, allowed to cool, and thereby to solidify.
[0034] Liquid form preparations include solutions, suspensions, and emulsions, for example, water or water propylene glycol solutions. For parenteral injection liquid preparations can be formulated in solution in aqueous polyethylene glycol solution.
[0035] Aqueous solutions suitable for oral use can be prepared by dissolving the active component in water and adding suitable colorants, flavors, stabilizing and thickening agents as desired.
[0036] Aqueous suspensions suitable for oral use can be made by dispersing the finely divided active component in water with viscous material, such as natural or synthetic gums, resins, methylcellulose, sodium carboxymethylcellulose, and other well-known suspending agents.
[0037] Also included are solid form preparations which are intended to be converted, shortly before use, to liquid form preparations for oral administration. Such liquid forms include solutions, suspensions, and emulsions. These preparations may contain, in addition to the active component, colorants, flavors, stabilizers, buffers, artificial and natural sweeteners, dispersants, thickeners, solubilizing agents, and the like.
[0038] The pharmaceutical preparation is preferably in unit dosage form. In such form the preparation is subdivided into unit doses containing appropriate quantities of the active component. The unit dosage form can be a packaged preparation, the package containing discrete quantities of preparation, such as packeted tablets, capsules, and powders in vials or ampoules. Also, the unit dosage form can be a capsule, table, cachet, or lozenge itself, or it can be the appropriate number of any of these in packaged form.
[0039] The quantity of active component in a unit dose preparation may be varied or adjusted from 0.1 mg to 1000 mg preferably 0.5 mg to 100 mg according to the particular application and the potency of the active component. The composition can, if desired, also contain other compatible therapeutic agents.
[0040] Cosmetic Uses
[0041] For preparing cosmetic compositions from the processes and compounds of the present invention, cosmetically acceptable vehicles or carriers facilitate distribution when the composition is applied to the skin. The vehicle may be aqueous, anhydrous or an emulsion. Preferably, the compositions are aqueous or an emulsion, especially water-in-oil or oil-in-water emulsion. Water when present will be in amounts which may range from about 5 to about 99%, in some embodiments from about 20 to about 70%, and in some embodiments between about 35 and 60% by weight.
[0042] Besides water, relatively volatile solvents may also serve as carriers within compositions of the present invention, such as transcutol. Most preferred are monohydric C 1 -C 3 alkanols. These include ethyl alcohol, methyl alcohol and isopropyl alcohol. The amount of monohydric alkanol may range from about 1 to about 70%, in some embodiments from about 10 to about 50%, and in some embodiments between about 15 and about 40% by weight.
[0043] Emollient materials may also serve as cosmetically acceptable carriers. These may be in the form of silicone oils and synthetic esters. Amounts of the emollients may range anywhere from about 0.1 to about 50%, in some embodiments between about 1 and about 20% by weight.
[0044] Silicone oils may be divided into the volatile and non-volatile variety. The term “volatile” as used herein refers to those materials which have a measurable vapor pressure at ambient temperature. Volatile silicone oils are preferably chosen from cyclic or linear polydimethylsiloxanes containing from 3 to 9, in some embodiments from 4 to 5 silicon atoms. Linear volatile silicone materials generally have viscosities less than about 5 centistokes at 25° C., while cyclic materials typically have viscosities of less than about 10 centistokes. Nonvolatile silicone oils useful as an emollient material include polyalkyl siloxanes, polyalkylaryl siloxones, and polyether siloxane copolymers. The essentially non-volatile polyalkyl siloxanes useful herein include, for example, polydimethyl siloxanes with viscosities of from about 5 to about 25 million centistokes at 25° C. Among the preferred non-volatile emollients useful in the present compositions are the polydimethyl siloxanes having viscosities from about 10 to about 400 centistokes at 25° C.
[0045] Among the ester emollients are: (1) alkenyl or alkyl esters of fatty acids having 10 to 20 carbon atoms. Examples thereof include isoarachidyl neopentanoate, isononyl isonanonoate, oleyl myristate, oleyl stearate, and oleyl oleate; (2) ether-esters such as fatty acid esters of ethoxylated fatty alcohols; (3) polyhydric alcohol esters. Ethylene glycol mono and di-fatty acid esters, diethylene glycol mono- and di-fatty acid esters, polyethylene glycol (200-6000) mono- and di-fatty acid esters, propylene glycol mono- and di-fatty acid esters, polypropylene glycol 2000 monooleate, polypropylene glycol 2000 monostearate, ethoxylated propylene glycol monostearate, glyceryl mono- and di-fatty acid esters, polyglycerol poly-fatty esters, ethoxylated glyceryl mono-stearate, 1,3-butylene glycol monostearate, 1,3-butylene glycol distearate, polyoxyethylene polyol fatty acid ester, sorbitan fatty acid esters, and polyoxyethylene sorbitan fatty acid esters are satisfactory polyhydric alcohol esters; (4) wax esters such as beeswax, spermaceti, myristyl myristate, stearyl stearate and arachidyl behenate; and, (5) sterols esters, of which cholesterol fatty acid esters are examples thereof; fatty acids having from 10 to 30 carbon atoms may also be included as cosmetically acceptable carriers for compositions of this invention. Illustrative of this category are pelargonic, lauric, myristic, palmitic, stearic, isostearic, hydroxystearic, oleic, linoleic, ricinoleic, arachidic, behenic and erucic acids.
[0046] Humectants of the polyhydric alcohol-type may also be employed as cosmetically acceptable carriers in compositions of this invention. The humectant aids in increasing the effectiveness of the emollient, reduces scaling, stimulates removal of built-up scale and improves skin feel. Typical polyhydric alcohols include glycerol, polyalkylene glycols and more preferably alkylen polyols and their derivatives, including propylene glycol, dipropylene glycol, polypropylene glycol, polyethylene glycol and derivatives thereof, sorbitol, hydroxypropyl sorbitol, hexylene glycol, 1,3-dibutylene glycol, 1,2,6-trihexanetriol, ethoxylated glycerol, propoxylated glycerol and mixtures thereof. In some embodiments the humectant is propylene glycol or sodium hyaluronate. The amount of humectant may range anywhere from about 0.5 to about 30%, in some embodiments between about 1 and about 15% by weight of the composition.
[0047] Thickeners may also be utilized as part of the cosmetically acceptable carrier of compositions according to the present invention. Typical thickeners include crosslinked acrylates (e.g. Carbopol 982), hydrophobically-modified acrylates (e.g. Carbopol 1382), cellulosic derivatives and natural gums. Among useful cellulosic derivatives are sodium carboxymethylcellulose, hydroxypropyl methylcellulose, hydroxypropyl cellulose, hydroxyethyl cellulose, ethyl cellulose and hydroxymethyl cellulose. Natural gums suitable for the present invention include guar, xanthan, sclerotium, carrageenan, pectin and combinations of these gums. Amounts of the thickener may range from 0.0001 to 5%, in some embodiments from 0.001 to 1%, and in some embodiments from 0.01 to 0.5% by weight.
[0048] Collectively the water, solvents, silicones, esters, fatty acids, humectants and/or thickeners will constitute the cosmetically acceptable carrier in amounts from about 1 to 99.9%, in some embodiments from 80 to 99% by weight.
[0049] An oil or oily material may be present, together with an emulsifier to provide either a water-in-oil emulsion or an oil-in-water emulsion, depending largely on the average hydrophilic-lipophilic balance (HLB) of the emulsifier employed.
[0050] Surfactants may also be present in cosmetic compositions. Total concentration of the surfactant can range from about 0.1 to about 40%, in some embodiments from 1 to 20%, and in some embodiments from 1 to 5% by weight of the composition. The surfactant may be selected from the group consisting of anionic, nonionic, cationic and amphoteric actives. In some embodiments, nonionic surfactants are those with a C 10 -C 20 fatty alcohol or acid hydrophobe condensed with from 2 to 100 moles of ethylene oxide or propylene oxide per mole of hydrophobe; C 2 -C 10 alkyl phenols condensed with from 2 to 20 moles of alkylene oxide; mono- and di-fatty acid esters of ethylene glycol; fatty acid monoglyceride; sorbitan, mono- and di-C 8 -C 20 fatty acids; block copolymers (ethylene oxide/propylene oxide); and polyoxyethylene sorbitan as well as combinations thereof. Alkyl polyglycosides and saccharide fatty amides (e.g. methyl gluconamides) are also suitable nonionic surfactants.
[0051] Preferred anionic surfactants include soap, alkyl ether sulfate and sulfonates, alkyl sulfates and sulfonates, alkylbenzene sulfonates, alkyl and dialkyl sulfosuccinates, C 8 -C 20 acyl isethionates, acyl glutamates, C 8 -C 20 alkyl ether phosphates and combinations thereof.
[0052] Sunscreens may be present in cosmetic compositions of the present invention. Sunscreens include those materials commonly employed to block ultraviolet light. Illustrative compounds are the derivatives of PABA, cinnamate and salicylate. For example, avobenzophenone (Parsol 1789®) octyl methoxycinnamate and 2-hydroxy-4-methoxy benzophenone (also known as oxybenzone) can be used. Octyl methoxycinnamate and 2-hydroxy-4-methoxy benzophenone are commercially available under the trademarks, Parsol MCX and Benzophenone-3, respectively. The exact amount of sunscreen employed in the compositions can vary depending upon the degree of protection desired from the sun's UV radiation.
[0053] Many cosmetic compositions, especially those containing water, must be protected against the growth of potentially harmful microorganisms. Preservatives are, therefore, often necessary. Suitable preservatives include alkyl esters of p-hydroxybenzoic acid, hydantoin derivatives, propionate salts, and a variety of quaternary ammonium compounds. In some embodiments, a preservative can be included selected from methyl paraben, propyl paraben, phenoxyethanol and benzyl alcohol. Preservatives can be present in amounts ranging from about 0.1% to 2% by weight of the composition.
[0054] Powders may be incorporated into the cosmetic composition of the invention. These powders include chalk, talc, Fuller's earth, kaolin, starch, smectites clays, chemically modified magnesium aluminum silicate, organically modified montmorillonite clay, hydrated aluminum silicate, fumed silica, aluminum starch octenyl succinate and mixtures thereof.
[0055] The composition can be packaged in a suitable container to suit its viscosity and intended use by the consumer. For example, a lotion or fluid cream can be packaged in a bottle or a roll-ball applicator, or a capsule, or a propellant-driven aerosol device or a container fitted with a pump suitable for finger operation. When the composition is a cream, it can simply be stored in a non-deformable bottle or squeeze container, such as a tube or a lidded jar.
[0056] Cosmetic formulations can be used in various fields. For example, the following preparations especially come into consideration: skin-care preparations, e.g. skin-washing and cleansing preparations in the form of tablet-form or liquid soaps, synthetic detergents or washing pastes; bath preparations, e.g. liquid (foam baths, milks, shower preparations) or solid bath preparations, e.g. bath cubes and bath salts; skin-care preparations, e.g. skin emulsions, multi-emulsions or skin oils; cosmetic personal care preparations, e.g. facial make-up in the form of day creams or powder creams, face powder (loose or pressed), rouge or cream make-up, eye-care preparations, e.g. eyeshadow preparations, mascara, eyeliner, eye creams or eye-fix creams; lip-care preparations, e.g. lipstick, lip gloss, lip contour pencils, nail-care preparations, such as nail varnish, nail varnish remover, nail hardeners, or cuticle removers; intimate hygiene preparations, e.g. intimate washing lotions or intimate sprays; foot-care preparations, e.g. foot baths, foot powders, foot creams or foot balsams, special deodorants and antiperspirants or callous-removing preparations; light-protective preparations, such as sun milks, lotions, creams, oils, sun blocks or tropicals, pre-tanning preparations or after-sun preparations; skin-tanning preparations, e.g. self-tanning creams; depigmenting preparations, e.g. preparations for bleaching the skin or skin-lightening preparations; insect-repellents, e.g. insect-repellent oils, lotions, sprays or sticks; deodorants, such as deodorant sprays, pump-action sprays, deodorant gels, sticks or roll-ons; antiperspirants, e.g. antiperspirant sticks, creams or roll-ons; preparations for cleansing and caring for blemished skin, e.g. synthetic detergents (solid or liquid), peeling or scrub preparations or peeling masks; hair-removal preparations in chemical form (depilation), e.g. hair-removing powders, liquid hair-removing preparations, cream- or paste-form hair-removing preparations, hair-removing preparations in gel form or aerosol foams; shaving preparations, e.g. shaving soap, foam shaving creams, non-foaming shaving creams, foams, gels, preshave preparations for dry shaving, aftershaves or aftershave lotions; fragrance preparations, e.g. fragrances (eau de Cologne, eau de toilette, eau de parfum, parfum de toilette, perfume), perfume oils or perfume creams; dental-care, denture-care and mouth-care preparations, e.g. toothpastes, gel tooth-pastes, tooth powders, mouthwash concentrates, anti-plaque mouthwashes, denture cleaners or denture fixatives; and, cosmetic hair-treatment preparations, e.g. hair-washing preparations in the form of shampoos and conditioners, hair-care preparations, e.g. pre-treatment preparations, hair tonics, styling creams, styling gels, pomades, hair rinses, treatment packs, intensive hair treatments, hair-structuring preparations, e.g. hair-waving preparations for permanent waves (hot wave, mild wave, cold wave), hair-straightening preparations, liquid hair-setting preparations, hair foams, hair sprays, bleaching preparations, e.g. hydrogen peroxide solutions, lightening shampoos, bleaching creams, bleaching powders, bleaching pastes or oils, temporary, semi-permanent or permanent hair colorants, preparations containing self-oxidizing dyes, or natural hair colorants, such as henna or camomile.
[0057] The compounds and compositions disclosed herein have significantly improved biological activity and can be stored over a long period without alteration.
[0058] The following non-limiting examples illustrate methods for preparing the compounds and compositions disclosed herein.
[0059] Nutritional Uses
[0060] When the composition is incorporated into various media such as foods, it may simply be orally ingested. The food can be a dietary supplement such as a snack or wellness dietary supplement or, especially for animals, comprise the nutritional bulk of a feedstock. The nutritional product may also be selected from an energy bar, cereal, beverage, energy drink, dip, yogurt, gum, and candy.
[0061] Mode or Route of Administration
[0062] The disclosed compositions may be administered in a topical cream, lotion, gel or other cosmetic formulation, where a resveratrol ester such as 4AR may be present in the form of a single analog or combined with other resveratrol ester analogs, in concentrations of about 0.3% to about 12% such as at least 0.3% to 2% or about 1.5% to 12%.
[0063] In some embodiments, the disclosed compositions may be administered in the form of a dermal patch delivery system to maintain systemic resveratrol ester levels, as a single analog or a combination of resveratrol ester analogs, in concentrations of from about 1% to about 30%. In some embodiments, the concentration of resveratrol ester is from 1% to 5% or between 4% and 30%.
[0064] In some embodiments, the disclosed compositions may be administered in an oral dosage by tablet, capsule, gelcap, liquid or other common method of administration, optionally including another resveratrol ester analog or combination of resveratrol ester analogs in concentrations of from about 10 mg to about 1600 mg, such as 10 mg to 50 mg, 40 mg to 500 mg, or 400 mg to about 1600 mg.
[0065] In some embodiments, the disclosed compositions may be administered by injection by subcutaneous, intra muscular or intravenous route to maintain systemic resveratrol ester levels as a single analog or a combination of resveratrol ester analogs in a concentration of from about 5 mg to about 1600 mg, such as 5 mg to 100 mg, 90 mg to 200 mg, or 180 mg to about 1600 mg.
[0066] In some embodiments, the disclosed compositions may be administered in food products such as an energy bar, cereal, beverage, energy drink, etc., optionally containing one or more resveratrol ester analogs in concentrations of from about 0.1% to about 10%, such as at least 0.1% to 5% or 4% to about 10%.
[0067] Synthesis of 4AR
[0068] Air and moisture sensitive reagents were introduced via dry syringe or cannula. Toluene, xylene, pyridine, ethyl acetate, and N-methyl morpholine were distilled from CaH 2 . DMF was dried by storage over 4 Å molecular sieves. Reagents were purchased from Aldrich and Lancaster. Flash chromatography was carried out using 60-230 mesh silica gel. Silica gel chromatography was performed using 1, 2, and 4 mm plates loaded with 230-400 mesh PF-254 gypsum bound silica. Analytical thin-layer chromatography (TLC) was performed with Merck silica gel 60 F 254 , 0.25 mm pre-coated TLC plates. TLC plates were visualized using UV 254 . All 1 H NMR spectra were obtained with 300 Varian spectrometers using TMS (0.00 ppm), chloroform (7.26 ppm), or acetone-d 6 (2.05 ppm) as an internal reference. Signals are reported as m (multiplet), s (singlet), d (doublet), t (triplet), q (quartet), and bs (broad singlet). 13 C NMR were obtained with 75 MHz Varian spectrometer using TMS (0.0 ppm), Chloroform (77.2 ppm), or acetone-d 6 (30.6 ppm) as the internal standard. Mass spectra date (HRMS, EI) were obtained from the Brigham Young University mass spectrometry facility. Combustion analysis was performed by M-H-W Laboratories, Phoenix, Ariz.
[0069] 4′-Acetoxy-resveratrol can be prepared according to Scheme 1.
[0000]
1. Preparation of 3,5-bis(methoxymethoxy)benzoic acid
[0070] A flame dried flask was charged with dry DMF (75 mL) and 60% oil dispersion NaH (3.8 g, 95 mmol). A solution of 3,5-dihydroxybenzoic acid (4.6 g, 30 mmol) in DMF (25 mL) was added dropwisely over 20 minutes. The mixture was allowed to stir for one hour under N 2 . MOMCl (7.5 mL, 100 mmol) was added slowly so that the inner temperature did not exceed 50° C. After 30 hours, the insoluble material was filtered off and the filtrate was concentrated to an oil residue, which was partitioned between benzene and water. The water layer was extracted with benzene for another three times. The combined benzene extracts was dried over Na 2 SO 4 and concentrated to pale yellow oil, which was dissolved in 50 mL methanol. 2N Aqueous NaOH (25 mL, 50 mmol) was added and the mixture was stirred for three hours. The mixture was concentrated and dissolved in 30 mL water. The aqueous solution was washed with benzene and acidified with 10% aqueous HCl. The precipitated white solid was filtered and washed with water and dried to give 6.6 g (91%) product, which was further purified by recrystallization from EtOAc-hexane. Data are: 1 H NMR (CDCl 3 , 300 MHz) δ 7.44 (d, 2H), 6.98 (t, 1H), 5.21 (s, 4H), 3.50 (s, 6H); 13 C NMR (CDCl 3 , 75 MHz) δ 170.9, 158.4, 131.4, 111.5, 110.7, 94.7, 56.4; mp=129-130° C.; HRMS (EI + ) found 242.0796 M + . calcd 242.0790 for C 11 H 14 O 6 .
2. Preparation of 3,5-bis(methoxymethoxy)benzoyl chloride
[0071] A stock solution was prepared by dissolving benzotriazole (1.49 g, 0.0125 mmol), thionyl chloride (0.91 mL, 0.0125 mmol) in 8.0 mL DCM. Reaction was carried out by adding the stock solution intermittently to a stirred solution of 3,5-dimethoxybenzoic acid (2.42 g, 10 mmol) in 200 ml DCM. Before addition was complete, benzotriazole hydrochloride started precipitating out as a white solid. The mixture was stirred for another ten minutes. After filtration, the filtrate was stirred with MgSO 4 7H 2 O (5 g) to destroy excess thionyl chloride. The white solid was filtered off and the filtrate was concentrated to give 2.5 g (97%) crude product, which was used for the next step without further purification. Data are: 1 H NMR (CDCl 3 , 300 MHz) δ 7.44 (d, 2H), 7.04 (t, 1H), 5.20 (s, 4H), 3.49 (s, 6H); 13 C NMR (CDCl 3 , 75 MHz) δ 168.1, 158.5, 135.3, 112.6, 111.9, 94.7, 56.4; HRMS (EI + ) found 260.0465 M + . calcd 260.0452 for C 11 H 13 O 5 Cl.
3. Preparation of 4′-acetoxy-3,5-bis(methoxymethoxy)stilbene
[0072] A 50 mL round bottom flask was charged with p-xylene (20 mL), Pd II catalyst (22.5 mg, 0.1 mmol), 1,3-bis-(2,6-diisopropylphenyl) imidazolinium chloride (42.7 mg, 0.1 mmol), 3,5-bis(methoxymethoxy)benzoyl chloride (2.42 g, 10 mmol), 4-acetoxystyrene (1.94 g, 12 mmol), and N-methyl morphorline (1.38 g, 12 mmol). The mixture was stirred at 120° C. for 3.5 h under nitrogen atmosphere. Then it was cooled to room temperature and EtOAc was added and filtered. The filtrate was washed with brine and dried over Na 2 SO 4 . Then it was filtered and purified via flash chromatography and gave the product (2.1 g, 59%) as a white solid. Data are: 1 H NMR (CDCl 3 , 300 MHz) δ 7.48 (d, 2H), 7.08-6.93 (m, 4H), 6.86 (d, 2H), 6.66 (t, 1H), 5.19 (s, 4H), 3.50 (s, 6H), 2.30 (s, 3H); 13 C NMR (CDCl 3 , 75 MHz) δ 169.5, 158.7, 150.3, 139.5, 135.0, 128.7, 128.5, 127.6, 121.9, 108.0, 104.5, 94.6, 56.2, 21.2; HRMS (EI + ) found 358.1409 M + . calcd 358.1416 for C 20 H 22 O 6
4. Preparation of 4′-acetoxy-3,5-dihydroxystilbene
[0073] To a solution of 4′-acetoxy-3,5-bis(methoxymethoxy)stilbene (0.358 g, 1 mmol) in dry DCM (50 mL) and dry CH 3 CN (50 mL) were added NaI (1.8 g, 24 mmol) and freshly distilled TMSCl (1.52 g, 24 mmol). The mixture was stirred under argon for 15 minutes. The solution was diluted with DCM (50 mL) and washed with a fresh aqueous saturated solution of Na 2 S 2 O 3 (3×40 mL) and saturated NaHCO 3 , and water. The organic layer was dried over Na 2 SO 4 , filtered, and concentrated. The crude product was purified by flash column and gave 0.20 g product (72%) of 4′-acetoxy-resveratrol. Data are: 1 H NMR (Aceton-d 6 , 300 MHz) δ 8.25 (s, 1H), 7.60 (m, 2H), 7.13-7.08 (m, 4H), 6.59 (d, 2H), 6.32 (t, 1H), 2.25 (s, 3H); 13 C NMR (Aceton-d 6 , 75 MHz) δ 169.7, 159.7, 151.4, 140.4, 136.0, 130.0, 128.3, 128.3, 123.0, 106.1, 103.3, 21.1; HRMS (EI + ) found 270.0889 M + . calcd 270.0892 for C 16 H 16 O 4 .
Example 1
Synthesis of 4AR
[0074] 4′-Acetoxy-Resveratrol (referred to herein as 4AR) is synthesized in five steps beginning with resorcyclic acid, as described above (see PCT/US05/02229). Treatment with sodium hydride followed by methoxylmethyl chloride and exposure to sodium hydroxide gave approximately a 71% isolated yield. Purification of this molecule was then performed using standard chemical protocols.
[0075] The 4AR synthesized as described above demonstrated increased bioavailability, as shown by an increase in CLog P value from 2.833 for resveratrol to 3.687 for 4AR, which indicates increased stability and bioavailability at significantly. The stability and methods of synthesis result in a reduced cost to provide the desired compositions.
[0076] The synthetic method described above uses a direct, efficient synthesis at a low cost, and results in improved stability (longer shelf life) where it remains a white crystalline material for over 2 years, as well as higher biological activity (increase absorption, lower dose and longer half-life) with various cosmetic, nutraceuticals (nutritional supplements) and pharmaceutical applications, including (a) anti-aging, anti-oxidant, (b) anti-inflammatory, (c) anti-cancer, (d) neuroprotection (for improved brain health), (e) cardiovascular health, (f) prostate health and (g) skin health, as described below in the following examples.
Example 2
Effect of 4AR on Collagen Deposition
[0077] 4′-Acetoxy-resveratrol was tested to determine whether it can stimulate collagen deposition in human monolayer dermal fibroblasts in the following examples. In this assay, we first determined the toxicity of the test materials (untreated cells, positive control-ascorbate, vehicle=0.1% DMSO, and a range of the 4′-acetoxy-resveratrol molecule, from approximately 10 nM to 10 μM).
[0078] Cytotoxicity was determined by spectrophotometric detection of reduced 3-(4,5-dimethlythiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT, Sigma Cat. #5655, lot #66H50336) at 550 nm. Metabolic activity can be used as a measure of cytotoxicity, in that the intensity of the reduced form of MTT by live cells is directly proportional to cell viability, and inversely proportional to cytotoxicity.
[0079] The human dermal monolayer fibroblasts were exposed to the test materials for approximately 48 hours. Thereafter, the samples were processed for MTT and collagen deposition, etc.
[0080] All test materials displayed similar MTT reduction (cytotoxicity) for the type of sample and dose range assayed (from approximately 10 nM to 10 μM). The number of replicates was 6 for each group.
[0081] Collagen deposition by ELISA for Human Type I collagen C-terminal propeptide was determined. Dermal fibroblasts synthesize primarily type I collagen, and the cleavage of the C-terminal propeptide is required for deposition into fibrils within the extracellular matrix. This propeptide can be measured using antisera which does not recognize the unprocessed from in cell culture supernatants, and is also used clinically as a measure of fibrosis in patient sera. The amount of cleaved propeptide is directly proportional to the amount of type I collagen deposited, and can be precisely quantified using purified standards and a commercial ELISA kit (Takara Mirus, Inc., Cat. # TAK-MK-101). After 48 hours in the presence of the test materials or controls, culture medium supernatants were removed and immediately analyzed using the ELISA kit according to manufacturer's instructions using a Molecular Devices Vmax plate 96 well plate reader and SoftMax software. Ascorbic acid (positive control; ascorbate, Sigma Cat. # A4544, lot #073K0139) was added to a final concentration of 20 μg/ml.
[0082] 4AR at approximately 9 μM significantly increased collagen deposition in human dermal monolayer fibroblasts by 65% compared to vehicle control values.
[0083] These basic dermal data results show that 4AR is biologically active in skin parameters with the ability to significantly increase collagen deposition in human monolayer fibroblasts and may positively influence many other dermal components such as elastin, elastase, matrix metalloproteinases, collagenases, glycoaminoglycans and hyaluronic acid at the epidermal/dermal junction (see gene arrays studies, below). Additionally, the resveratrol analogs can bind the abundant distribution of beta estrogen receptors in the keratinocytes of the epidermis and fibroblasts in the dermis that also have a positive influence on skin parameters and enhanced dermal health.
Example 3
Effect of 4AR on Body Weight Gain
[0084] Adult male Long-Evans rats were administered 4AR for 21 days. DMSO served as the control and 4AR was dissolved into DMSO at the following concentrations: 5.0 mg/kg body weight, 20.0 mg/kg body weight and 90.0 mg/kg body weight (n=12 per group). There were no significant differences in food/water intake during the course of this study among the treatment groups.
[0085] After 10 days of receiving the treatments there was a significant decrease in body weight gain, by an average of approximately 17 grams, in the 90.0 mg/kg vs. the control values (525.0+5.1 vs. 542.1+6.2 grams, respectively. After 20 days on the treatments there was a significant decrease in body weight gain, by approximately 14 grams, in the 20.0 mg/kg vs. control values (566.0+4.7 vs. 551.8+3.7 grams). Finally, there was an even greater significant decrease in body weight gain between the 90.0 mg/kg vs. control values after 20 days on the treatments representing a 54.2 grams decrease (or 566.0+4.7 vs. 511.8+4.1 grams). These data suggest a positive influence of the resveratrol ester analog on body weight gain or weight control.
Example 4
Effect of 4AR on 5α-Reductase Enzyme Activity
[0086] Since, the 5a-reductase enzyme (which converts testosterone to 5a-dihydrotestosterone) is important in prostate health in reference to benign prostatic hyperplasia (BPH) and the treatment and prevention of prostate cancer, we determined if prostate type I 5α-reductase enzyme activity was impacted by these treatments by quantifying the enzymatic rates of each animal as described above (in this study there were approximately 10 animals per treatment group).
[0087] Table 1 shows the effect of 4AR on 5a-reductase enzyme activity as measured in pmol/hour incubation/mg of protein.
[0000] TABLE 1 SAMPLE TYPE ACTIVITY DMSO-Controls 8.7 + 0.6 5 mg/kg Body Weight (4AR) 4.6 + 0.4* 20 mg/kg Body Weight (4AR) 3.3 + 0.3* 90 mg/kg Body Weight (4AR) 2.0 + 0.2* *denotes a significant decrease in 5α-reductase enzyme activity in the 4AR treated rats compared to the DMSO-control values.
These data show a significant and positive influence of the 4AR resveratrol analog on male prostate health as a potential treatment for benign prostatic hyperplasia (BPH) and the prevention of prostate cancer by significantly decreasing 5α-reductase enzyme activity.
Example 5
Gene Expression Studies
[0088] In this gene array experiment, we examined the ability of 4AR at a one percent concentration in DMSO (where 100% DMSO served as the vehicle) to either stimulate or inhibit several important genes and quantify directly the transcribed messenger RNA (mRNA) levels by Taqman real time PCR. The test material was placed onto a biological barrier (human dermal equivalent) using a MatTek “ready-to-use” in vitro organotypic tissue equivalent, based on well-documented and validated protocols, using the EpiDerm™ Model EPI-200 Kit. The MatTek kits uses normal (non-transformed) donated human cells as the basis for all of its tissue equivalents. These cells are grown (cultured) in standard Millipore Millicell™ Single Well Tissue Culture Plate Inserts at the air liquid interface or ALI. Apical (top) surface of tissue is exposed to air allowing for direct application of test articles. DMSO only treated samples served as controls along with untreated samples. Once the 4 AR test material penetrated the human skin barrier equivalent the gene chip was activated and subsequently mRNA levels were quantified and the results represent stimulation or inhibition of a specific gene.
[0089] The in vitro human dermal tissue model that served as the biological barrier in these gene array studies is shown in FIG. 1 .
[0090] To investigate the effects of 4AR on the expression of genes associated with the extracellular matrix (ECM) of the skin, qPCR experiments were conducted using the tissue cultures (model system described above) with subsequent quantification of mRNA levels from neurosensory tissue/cells. There are many genes involved in skin health that include ECM proteins and several other gene products that are involved in inflammation, anti-oxidant activity, anti-aging, regulators of ECM factors and DNA repair (Baumann LS, 2009, Cosmetic Dermatology: Principles and Practice, Revised 2nd edition, McGraw-Hill, Columbus, Ohio, USA.; Wolff K, Goldsmith L, Katz S et al (eds), 2008, Collagen, Elastic Fibers, and Extracellular Matrix of the Dermis. In: Fitzpatrick's Dermatology in General Medicine 7th edition, McGraw-Hill, Columbus, Ohio, USA, Chapter 61). A dose of 1.0% of 4AR dissolved in 100% DMSO along with the other control treatments (outlined above) were exposed to the human equivalent skin model for 24 hours.
[0091] The results of a gene array study examining 4AR as an example of a novel topical agent for cosmetic applications displayed below in Summary Table 2.
[0000]
TABLE 2
Gene Function Summary
Assay result
Gene Marker
Reported Role
Reporting Reference(s)
with 4AR
A. Anti-Aging
Anti-aging, biological
http://genomics.senescence.info/
SIRT1
Marker: SIRT1
activity on human skin
genes/entry.php?hgnc=SIRT1
activity
(Sirtuin 1)
cells activates the
http://findarticles.com/p/articles/mi_m0PDG/is_6_6/
increased by
nuclear longevity protein
ai_n19328744/pg_4/?tag=content;col1
3.3-fold
SIRT1, improving DNA
integrity and acts as a
anti-senescence marker
B. Collagen/ECM
Play significant roles in
http://www3.interscience.wiley.com/
Tissue
formation and
wound repair
journal/90510948/abstract
inhibitor of
breakdown:
Elevates collagen levels
http://www.jbc.org/content/270/7/3423.abstract
metalloproteinases 1
Tissue inhibitor of
Youth marker
increased by
metalloproteinases 1
2.5-fold
B. Collagen/ECM
Major component in
http://www.pnas.org/content/85/24/9679.abstract
Type IV
formation and
basement membranes
collagen
breakdown: Type
Involved in collagen
alpha 1
IV collagen alpha 1
production
increased by
1.7-fold
B. Collagen/ECM
Major component in
http://www.pnas.org/content/85/24/9679.abstract
IV collagen
formation and
basement membranes
alpha 2
breakdown: Type
Involved in collagen
increased by
IV collagen alpha 2
production
1.8-fold
B. Collagen/ECM
Promotes collagen that
http://askville.amazon.com/Cheap-place-buy-Epicuren-
Procollagen
formation and
is found in youthful skin
Pro-Collagen-III/AnswerViewer.do?requestId=11938437
III increased
breakdown:
Anti-wrinkle
by 2.2-fold
Procollagen III
(alpha 1)
B. Collagen/ECM
Youth marker, increased
Jo Seltzer and Arthur
TIMP2
formation and
by Vitamin C
Eisen, 2003, The Role of
increased by
breakdown:
Extracellular Matrix
1.3-fold
Tissue Inhibitor of
Metalloproteinases in
metalloproteinases
Connective Tissue
2 (TIMP2)
Remolding, In:
Fitzpatrick's Dermatology
in General Medicine 6th
edition, McGraw-Hill, New
York, NY, USA, Chapter
17
B. Collagen/ECM
Regulates MMP 1
http://en.wikipedia.org/wiki/MMP1
Protein
formation and
expression which breaks
Kinase C
breakdown:
down interstitial
alpha
Protein Kinase C
collagens
increased by
alpha
2.7-fold
B. Collagen/ECM
A protein in connective
http://en.wikipedia.org/wiki/Elastin
Elastin
formation and
tissue that is elastic and
increased by
breakdown: Elastin
allows many tissues in
2.8-fold
the body to resume their
shape after stretching or
contracting. Elastin
helps skin to return to its
original position when it
is poked or pinched
C. Inflammation:
Proinflammatory
http://en.wikipedia.org/wiki/Interleukin
IL-6
IL-6 (interleukin 6)
decreased by
35.2-fold
C. Inflammation:
Proinflammatory
http://www.genecards.org/cgi-
IL-1a
IL-1a (interleukin
marker of irritancy
bin/carddisp.pl?gene=II1a
decreased by
1a)
Induces apoptosis
10.1-fold
C. Inflammation:
Proinflammatory
http://en.wikipedia.org/wiki/Interleukin_8
IL-8
IL-8 (interleukin 8)
especially in response to
decreased by
psoriasis
3.8-fold
C. Inflammation:
Proinflammatory,
http://www3.interscience.wiley.com/journal/
S100
S100 Calcium
especially in psoriasis
118568631/abstract?CRETRY=1&SRETRY=0
Calcium
binding protein A8
binding
protein A8
decreased by
2.7-fold
C. Inflammation:
Proinflammatory
http://books.google.com/books?id=5XKs5ACErHgC&pg=
IL-1RII
IL-1RII (interleukin
PA352&lpg=PA352&dq=il-1rii+in+skin&source=
decreased by
1RII)
bl&ots=k9KOhgWNdm&sig=
1.9-fold
AwTEv80VjTiajNa4Zk1BR8WDxbM&hl=
en&ei=QWbJSsvAGlu_lAfUjZmSAw&sa=
X&oi=book_result&ct=result&resnum=
2#v=onepage&q=il-1rii%/20in%20skin&f=false
C. Inflammation:
Proinflammatory
14. cyclooxygenase-2: an
COX 2
COX 2 (PTGS2)
enzyme that makes
decreased by
prostaglandins that cause
1.7-fold
inflammation and pain and
fever;
wordnetweb.princeton.edu/perl/webwn
C. Inflammation:
Proinflammatory,
http://www3.interscience.wiley.com/
S100
S100 Calcium
especially in psoriasis
journal/118568631/abstract?CRETRY=1&SRETRY=0
Calcium
binding protein A9
binding
protein A9
decreased by
1.6-fold
C. Inflammation:
Induces apoptosis
http://www.genecards.org/cgi-bin/
TNFRSF1A
TNFRSF1A
Proinflammatory
carddisp.pl?gene=TNFRSF1A
decreased by
(Tumor necrosis
Increases with age
1.4-fold
factor receptor
superfamily,
member 1A)
D. Anti-oxidant:
redox and oxidative
http://genomics.senescence.info/
Superoxide
Superoxide
regulation
genes/entry.php?hgnc=SOD1
dismutase 1,
dismutase 1,
Antioxidant activity
soluble
soluble
increased by
1.6-fold
D. Anti-oxidant:
redox and oxidative
http://genomics.senescence.info/
Superoxide
Superoxide
regulation
genes/entry.php?hgnc=SOD2
dismutase 2,
dismutase 2,
Anti-oxidant activity
mitochondrial
mitochondrial
increased by
1.7-fold
D. Anti-oxidant:
cross-linking collagen
http://en.wikipedia.org/wiki/Lysyl_oxidase
Lysyl oxidase
lysyl oxidase
and elastin
increased by
(LOX)
1.9-fold
D. Anti-oxidant:
Antioxidant agent
http://www.accessmylibrary.com/coms2/
Metallothionein 2
Metallothionein 2
summary_0286-31734665_ITM
increased by
3.4-fold
D. Anti-oxidant:
Antioxidant agent
http://www.accessmylibrary.com/coms2/
Metallothionein 1
Metallothionein 1
summary_0286-31734665_ITM
increased by
64.0-fold
D. Anti-oxidant:
Antioxidant, prevents
http://www.rcsb.org/pdb/static.do?p=education_discussion/
Catalase
Catalase
free radical damage
molecule_of_the_month/pdb57_1.html
increased by
1.6-fold
E. Growth factors:
tumor suppressor gene
http://en.wikipedia.org/wiki/
TGF beta
TGF (transforming
This receptor/ligand
TGF_beta_receptor_2
type II
growth factor) beta
complex phosphorylates
receptor
type II receptor
proteins, which then
increased by
enter the nucleus and
1.7-fold
regulate the transcription
of a subset of genes
related to cell
proliferation
Induces procollagen I
and III
Reduced after UV
exposure
E. Growth factors:
Growth factor, especially
http://stke.sciencemag.org/cgi/
HBEGF
HBEGF (Heparin-
in healing wounds in
content/abstract/develop;132/19/4317
increased by
binding EGF-like
epithelial tissue
1.9-fold
growth factor)
E. Growth factors:
controls proliferation,
http://en.wikipedia.org/wiki/TGF_beta
TGF beta
TGF (transforming
cellular differentiation
increased by
growth factor) beta
acts as an
2.0-fold
antiproliferative factor in
normal epithelial cells
and at early stages of
oncogenesis
induces procollagen I
and III
E. Growth factors:
stimulates growth
http://genomics.senescence.info/
IGF1
IGF1 (Insulin-like
genes/entry.php?hgnc=IGF1
increased by
growth factor 1)
2.6-fold
E. Growth factors:
A neurotrophin important
http://genomics.senescence.info/
Nerve growth
Nerve growth
for the development and
genes/entry.php?hgnc=NGF
factor
factor
maintenance of the
A Micera et al. PNAS,
increased by
central nervous system,
2001, 98: 6162-6167
6.7-fold
NGF stimulates division
and differentiation
Growth and
development
PNS development
Involved in tissue repair
F. Cell adhesion/
Desmocollin 1 is part of
http://www.in-cosmeticsasia.com/ExhibitorLibrary/
Desmocollin
desmosomes:
a desmosomal cell
59/Skin_rejuvenation_with_a_biomimetic_pep-
1 decreased
Desmocollin 1
adhesion receptor
tide_designed_to_promote —-
by 2.4-fold
formed in terminally
desquamation_SOFW_2006_3.pdf
differentiating
keratinocytes of stratified
epithelia.
Overexpression in old
skin (a decrease would
be a sign of youth)
F. Cell adhesion/
Desmosomes are cell-
http://www.in-cosmeticsasia.com/ExhibitorLibrary/
Desmoglein
desmosomes:
cell junctions between
59/Skin_rejuvenation_with_a_biomi-
3 decreased
Desmoglein 3
epithelial, myocardial,
metic_peptide_designed_to_promote_desquama-
by 1.9-fold
and certain other cell
tion_SOFW_2006_3.pdf
types. Desmoglein 3 is a
http://en.wikipedia.org/wiki/
calcium-binding
Desmoglein_3
transmembrane
glycoprotein component
of desmosomes in
vertebrate epithelial
cells.
G. NF-KB/AP-1
Decreased in aged skin
http://www.sciencedirect.com/science?_ob=
JunD
Signaling
ArticleURL&_udi=B6T6J-4JFHF2T-
increased by
Pathways: JunD
2&_user=456938&_rdoc=
2.1-fold
1&_fmt=&_orig=
search&_sort=d&_docanchor=
&view=c&_searchStrId=
1059942232&_rerunOrigin=
google&_acct=C000021830&_version=
1&_urlVersion=0&_userid=
456938&md5=ae5efdcd07b60060a081832dbc5f2f0c
G. NF-KB/AP-1
The FOS oncogene
http://genomics.senescence.info/
Fos
Signaling
plays an important role
genes/entry.php?hgnc=FOS
increased by
Pathways: Fos
in development, cell
3.4-fold
(FBJ murine
proliferation, and
osteosarcoma viral
differentiation
oncogene)
Decreased in aging skin
G. NF-KB/AP-1
regulators of cell
http://en.wikipedia.org/
FosB
Signaling
proliferation,
wiki/FOSB
increased by
Pathways: FosB
differentiation, and
8.2-fold
(FBJ murine
transformation
osteosarcoma viral
Decreased in aging skin
oncogene
homolog B)
H. Cellular Growth/
A photomarker for aging
http://www3.interscience.wiley.com/
Fibrillin
regeneration:
skin so helps skin stay
journal/118683054/abstract
increased by
Fibrillin
younger and healthier
1.3-fold with
4AR
H. Cellular Growth/
Glycoprotein important
http://www.antibodies-online.com/
Laminin 1B
regeneration:
for basement membrane
antigen/laminin,+gamma+1+
increased by
Laminin 1B
health
(formerly+LAMB2)+(LAMC1)/
1.4-fold with
4AR
H. Cellular Growth/
Repair of DNA,
http://www.pubmedcentral.nih.gov/
PCNA
regeneration:
decreased in aged skin
articlerenderfcgi?artid=1483034
increased by
PCNA
http://escience.invitrogen.com/ipath/
5.4-fold with
(Proliferating Cell
iPath.jsp?cn=
4AR
Nuclear Antigen)
United%20States&mapid=
427&highlightGene=PCNA
H. Cellular Growth/
Increased in aged skin
http://www.molecularstation.com/research/
CK 2E
regeneration:
protein-kinase-ck2-is-a-key-activator-
decreased by
Cytokeratin 2E
of-histone-deacetylase-in-hypoxia-
3.5-fold with
associated-tumors-17935135.html
4AR | The present invention relates to a method of providing enhanced resveratrol activity comprising: administering a therapeutically effective amount of 4-acetoxy-resveratrol for the treatment of and preventing physiological and pathophysiological conditions mediated by (1) sirtuins, (2) estrogen and anti-estrogen hormone actions and (3) chemical interventions important for male and female health, aging, anti-aging and age-related disorders. | 0 |
FIELD
[0001] The invention relates to an implant and a method for improving coaptation of an atrioventricular valve.
BACKGROUND
[0002] Atrioventricular valves are membraneous folds that prevent backflow from the ventricles of the human heart into the atrium during systole. They are anchored within the ventricular cavity by chordae tendineae, which prevent the valve from prolapsing into the atrium.
[0003] The chordae tendineae are attached to papillary muscles that cause tension to better hold the valve. Together, the papillary muscles and the chordae tendineae are known as the subvalvular apparatus. The function of the subvalvular apparatus is to keep the valves from prolapsing into the atria when they close. The opening and closure of the valves is caused by the pressure gradient across the valve.
[0004] The human heart comprises two atrioventricular valves, the mitral valve and the tricuspid valve. The mitral valve allows the blood to flow from the left atrium into the left ventricle. The tricuspid valve is located between the right atrium and the right ventricle. The mitral valve has two leaflets that are each divided into several scallops: the anterior leaflet has three scallops (A1,A2,A3), the posterior leaflet has three scallops (P1,P2,P3). The tricuspid valve has three leaflets. Engagement of corresponding surfaces of the leaflets against each other is decisive for providing closure of the valve to prevent blood flowing in the wrong direction. The closure forms a so called coaptation area.
[0005] Native heart valves become dysfunctional for a variety of pathological causes. Failure of the leaflets to seal during ventricular systole is known as malcoaptation, and may allow blood to flow backward through the valve (regurgitation). Malcoaptation is often caused by a dilatation of the annulus. Another reason is a restriction in motion or an excessive motion of the leaflet structures. Heart valve regurgitation can result in cardiac failure, decreased blood flow, lower blood pressure, and/or a diminished flow of oxygen to the tissues of the body. Mitral regurgitation can also cause blood to flow back from the left atrium to the pulmonary veins, causing congestion and backward failure.
[0006] Some pathologies of atrioventricular valves, such as malcoaptation, often require reconstruction of the valvular and subvalvular apparatus as well as redesigning the enlarged annulus. Sometimes a complete surgical replacement of the natural heart valve with heart valve prosthesis is necessary. There are two main types of artificial heart valves: the mechanical and the biological valves. The mechanical-type heart valve uses a pivoting mechanical closure supported by a base structure to provide unidirectional blood flow. The tissue-type valves have flexible leaflets supported by a base structure and projecting into the flow stream that function similar to those of a natural human heart valve and imitate their natural flexing action to coapt against each other. Usually two or more flexible leaflets are mounted within a peripheral support structure made of a metallic or polymeric material. In transcatheter implantation the support within the annulus may be in the form of a stent, as is disclosed in US 2011/0208298 A1.
[0007] In order to provide enough space for the artificial leaflets to work properly, the peripheral support is positioned in the native valve so as to force the native leaflets apart. To this end and in order to provide appropriate anchoring of the peripheral support within the native valve, the same is fixed to the native leaflets by suitable means. However, in some applications, such as with mitral valves, fixing the peripheral support to the native anterior leaflet and dislocating the same from its natural position may cause an obstruction of the outflow tract and of the aortic valve, which is located in the left ventricle immediately adjacent the anterior leaflet.
[0008] The gold standard for treating mitral regurgitation is to repair the mitral apparatus including leaflets and the subvalvular apparatus and to reshape the mitral annulus (Carpentier technique). If repair is not possible an excision of the valve including parts of the subvalvular apparatus is performed with subsequent implantation of a heart valve prosthesis. This is necessary particularly when the valve is destructed by inflammation. Although in most instances a complete excision of the destroyed valve is necessary, sometimes a partial replacement is possible. A clinically used mitral valve restoration system (Mitrofix®) replaces only the posterior leaflet with a rigid prosthesis mimicking a fixed posterior leaflet allowing the natural anterior leaflet to coapt. This prosthesis is also sewn into the position of the destroyed posterior aspect of the annulus. This requires open heart surgery and extended cardiac arrest.
[0009] Recent trends focus on less invasive procedures to minimize surgical trauma and to perform transcatheter approaches including transatrial, transaortal or transapical procedures to replace or reconstruct dysfunctional valves thus minimizing the need of or avoiding heart lung machine and cardiac arrest. Whereas this is a common procedure in aortic valves nowadays, only few mitral valves insufficiencies are corrected by percutaneous or transapical procedures. Most of these concepts are redesigning and remodeling artificially the mitral annulus to allow coaptation or to enforce coaptation by fixing both leaflets together with a clip reducing mitral regurgitant flow. Percutaneously or transapically deployed valve prostheses are difficult to anchor due to the special anatomy of the mitral valve and the vicinity of the anterior leaflet to the aortic outflow tract.
SUMMARY
[0010] Therefore, it is an object of the instant invention to provide an improved implant for improving coaptation of an atrioventricular valve. In particular, it is an object of the invention to provide an implant that does not involve the risk of stenosis of the aortic valve.
[0011] It is a further object of the invention to provide an implant that can be easily deployed to the target site.
[0012] It is a further object of the invention to use preoperative imaging data to construct a posterior leaflet according to the patient's pathologic anatomy.
[0013] The invention generally provides improved medical implants and methods for the treatment of regurgitation in atrioventricular valves, in particular mitral valves. In some embodiments, the invention provides a medical implant that provides replacement of one of the two or three native leaflet parts of atrioventricular valves, while leaving the other native leaflet(s) fully functional. In case of an implant configured for mitral valves, the medical implant preferably provides replacement of the native posterior leaflet, while leaving the native anterior leaflet fully functional. Preferably, the implant does not comprise any structure that is fixed to the anterior leaflet. When configured for the mitral valve, the implant preferably affects only one half of the valve, and only extends over the region of the posterior leaflet.
[0014] In the context of the instant invention, the terms “replacement” and “replacing” mean that the artificial leaflet replaces the function of a damaged or otherwise malfunctional native leaflet. However, the damaged or otherwise malfunctional native leaflet is not physically removed. Rather, the damaged or otherwise malfunctional native leaflet is left in the valve. The damaged or otherwise malfunctional native leaflet may be at least partially displaced by the artificial leaflet of the invention. Further, and the damaged or otherwise malfunctional native leaflet may support the function of the artificial leaflet.
[0015] In some embodiments, the artificial leaflet is flexible in order to allow the artificial leaflet to behave like the artificial leaflet it replaces. In particular, the artificial is flexible at least in its lower end region, i.e. the end region facing the ventricular cavity.
[0016] In some embodiments, the invention provides an implant for improving coaptation of an atrioventricular valve, the atrioventricular valve having a native first leaflet, a native second leaflet and an annulus, the implant comprising a support structure and a flexible artificial leaflet structure mounted to the support structure and shaped to coapt with the native second leaflet.
[0017] In some embodiments, the invention provides an implant for improving coaptation of an atrioventricular valve, the atrioventricular valve having a native first leaflet, a native second leaflet and an annulus, the annulus having a substantially semicircular first segment, from which the native first leaflet emerges, and a substantially semicircular second segment, from which the native second leaflet emerges, the implant comprising a support structure and an artificial leaflet structure mounted to the support structure and shaped to coapt with the native second leaflet, said support structure being anchored only to the first segment of the annulus.
[0018] In case of an implant configured for mitral valves, the first native leaflet is a posterior leaflet of the mitral valve and the second native leaflet is an anterior leaflet of the mitral valve. The artificial leaflet is configured as an artificial posterior leaflet and replaces and/or supports the function of the native posterior leaflet. The artificial posterior leaflet is preferably shaped such as to improve coaptation with the native anterior leaflet.
[0019] In case of an implant configured for tricuspid valves, the first native leaflet is an anterior leaflet of the tricuspid valve and the second native leaflet is a posterior leaflet and the third leaflet is the septal leaflet of the tricuspid valve. The artificial leaflet is configured to replace the function of the native anterior and or posterior leaflet. The artificial anterior or posterior leaflet or the combination of both is preferably shaped such as to improve coaptation with the native anterior and posterior leaflet.
[0020] The support structure is configured to carry the artificial leaflet structure and to hold the artificial leaflet structure in a position, in which it can coapt with the native second leaflet. Preferably, the artificial leaflet is held in a position closer to the native second leaflet when compared to the position of the malcoapting native first leaflet. In particular, the artificial leaflet bears against the native second leaflet and, depending on the degree of pathological dilatation of the annulus, displaces the native first leaflet to a location closer to the wall of the ventricle when compared to its original location.
[0021] In order to associate the implant to the annulus, the support structure preferably comprises an upper support element and a lower support element displaceable relative to each other so as to be able to squeeze a section of the annulus between them in order to avoid improper paravalvular leakage and regurgitation.
[0022] The upper support element preferably is substantially U-shaped, semicircular or circular so as to conform to the shape of the annulus or a section of the annulus. In order to stabilize the upper support element, the upper support element preferably comprises bracing means for applying a radial bracing force across the annulus and the adjacent atrial wall. The bracing force acts so as to spread apart the annulus, so as to firmly hold the upper support element relative to the annulus.
[0023] In some embodiments of the invention, the upper support element extends only over the first segment of the annulus.
[0024] Fixing the support structure relative to the annulus preferably comprises arranging the upper support element at least partially within the inner circumferential surface of the annulus and expanding the upper support element in a radial direction towards the inner circumferential surface of the annulus.
[0025] In order to enable an expansion of the upper support element so as to apply said bracing force, the support structure preferably comprises a cavity. The upper support element is preferably expanded by filing a filling material into a cavity. The filling material may be selected from the group consisting of a fluid, an elastic solid, such as a foamed material, and a gel. The cavity preferably comprises a closable opening for filling the cavity with the filling material. The filling material is preferably filled into the cavity after the implant has been deployed to the heart. Alternatively, the upper support element is expanded by expanding a filling material contained in the cavity. In this case, the filling material may be already present in the cavity before the implant is deployed to the heart. The filling material may be a liquid that forms a foamed structure as soon as a chemical reaction is initiated by applying heat, radiation, water or the like.
[0026] Further, the lower support element of the support structure preferably comprises a cavity. The lower support element is preferably expanded by filing a filling material into a cavity. The filling material may be selected from the group consisting of a fluid, an elastic solid, such as a foamed material, and a gel. The cavity preferably comprises a closable opening for filling the cavity with the filling material. The filling material is preferably filled into the cavity after the implant has been deployed to the heart. Alternatively, the lower support element is expanded by expanding a filling material contained in the cavity. In this case, the filling material may be already present in the cavity before the implant is deployed to the heart. The filling material may be a liquid that forms a foamed structure as soon as a chemical reaction is initiated by applying heat, radiation, water or the like.
[0027] Due to the expansion of the upper support element and/or the lower support element the annulus can be effectively squeezed between the upper and the lower support element.
[0028] According to another preferred embodiment, the artificial leaflet structure comprises a cavity. The closed cavity contains or may be filled with a filling material so as to expand to a defined shape and volume. Once expanded, the artificial leaflet structure has an increased structural stability and may adopt a defined surface shape that improves coaptation with the native second leaflet. The artificial leaflet structure may comprise several cavities that are connected with each other. The filling material may be selected from the group consisting of a fluid, an elastic solid, such as a foamed material, and a gel. The cavity preferably comprises a closable opening for filling the cavity with the filling material. The filling material is preferably filled into the cavity after the implant has been deployed to the heart. Alternatively, the artificial leaflet is expanded by expanding a filling material contained in the cavity. In this case, the filling material may be already present in the cavity before the implant is deployed to the heart. The filling material may be a liquid, that forms a foamed structure as soon as a chemical reaction is initiated by applying heat, radiation, water or the like. In some embodiments the filled semiflexible material is sculptured by the mechanical force of the second leaflet within the first closing attempts until the filled material receives its permanent shape.
[0029] Preferably, the cavity of the artificial leaflet structure and the cavity of the support structure are connected to each other to form a single cavity.
[0030] In some embodiments, the invention provides an implant for improving coaptation of an atrioventricular valve, the implant comprising a support structure and a flexible artificial leaflet structure mounted to the support structure and shaped to coapt with the native second leaflet, wherein the support structure and the artificial leaflet structure are deployable from a first position, in which the support structure and the artificial leaflet structure are arranged within the tubular housing, into a second position, in which the artificial leaflet structure is deployed to coapt with the second native leaflet. In this way, the implant can be easily deployed to the heart by minimal invasive surgery. In particular, the tubular housing is preferably advanced into the heart by means of a catheter transatrially, transseptally, transfemorally or transapically.
[0031] Preferably, the support structure and the artificial leaflet structure are configured to be deployed from a folded or rolled-up state into an extended state. In the folded or rolled-up state, the structures may easily be advanced to the heart transcatheterally.
[0032] The artificial leaflet may be made of a biocompatible material, such as polyethylene or polyurethane, polyfluorethylen (Goretex®) or from natural tissue such as heterologic pericardium.
[0033] The support structure preferably comprises a wire of a memory-shape material, such as Nitinol.
[0034] Preferably, the implant further comprises retention means connected to the support structure and the artificial leaflet for preventing prolapse of the artificial leaflet.
[0035] According to a further aspect the invention refers to a method of improving coaptation of an atrioventricular valve, the atrioventricular valve having an annulus, a native first leaflet and a native second leaflet, the method comprising:
providing an implant comprising a support structure and a flexible artificial leaflet structure mounted to the support structure, the implant being arranged in a tubular housing, advancing the tubular housing by means of a catheter through a body vessel of a patient into the heart, deploying the implant from the tubular housing, fixing the support structure relative to the annulus, arranging the artificial leaflet structure adjacent the native first leaflet such that the artificial leaflet structure can coapt with the native second leaflet.
[0041] Preferably, the native first leaflet is a native posterior leaflet of a mitral valve and the second native leaflet is an anterior leaflet of the mitral valve. The artificial leaflet is configured as an artificial posterior leaflet and replaces the normal function of the native posterior leaflet. The artificial posterior leaflet is preferably shaped such as to improve coaptation with the native anterior leaflet.
[0042] Preferably, the tubular housing is advanced into the heart by means of a catheter transatrially, i.e. through the left atrium of the heart, transseptally, i.e. through the septum of the heart, transfemorally or transapically, i.e. through the apex of the heart. The positioning is facilitated by a steerable guiding element to maneuver the deployable element into the rim of the annulus connecting the ventricular wall with the leaflet structure.
[0043] Preferably, the step of fixing the support structure relative to the annulus comprises positioning an upper support element on a superior surface of the annulus and positioning a lower support element on an inferior surface of the annulus thereby clamping a section of the annulus between the upper support element and the lower support element.
[0044] Preferably, the step of fixing the support structure relative to the annulus comprises arranging the upper support element at least partially within the inner circumferential surface of the annulus and expanding the upper support element in a radial direction towards the inner circumferential surface of the annulus.
[0045] Preferably, the upper support element is expanded by filling a filling material into a cavity of the upper support element.
[0046] Preferably, the upper support element is expanded by expanding a filling material arranged in a cavity of the upper support element.
[0047] Preferably, the lower support element is expanded by filling a filling material into a cavity of the lower support element.
[0048] Preferably, the lower support element is expanded by expanding a filling material arranged in a cavity of the lower support element.
[0049] Preferably, the method further comprises connecting the artificial leaflet to the support structure by the aid of retention means for preventing prolapse of the artificial leaflet.
[0050] In some embodiments, the invention provides a method comprising the steps of
imaging the native mitral valve prior to the procedure, identifying and localizing the areas of malcoaptation, measuring leaflet heights in all three scallops (p1,p2,p3) and their form and the two indentations, measuring the extend of the posterior leaflet, virtual reconstructing of an artificial posterior leaflet with scallops and artificial chordae, implementing the patient's mitral valve into a computer model, thereby obtaining 3D data of the mitral valve, adapting the 3D data in the computer model to improve coaptation, using the adapted 3D data from the computer model to obtain 3D data representative of the three scallops as well as of the wall coverage of the posterior leaflet, 3D printing of artificial scallops of the posterior leaflet from said 3D data, using the artificial scallops as a model and building an artificial posterior leaflet on said model, optionally including modeling cushion sizes and forms for the definite coaptation surface area, connecting the artificial posteriori leaflet to a support structure, folding the support structure and the artificial leaflet and arranging the same into a tubular housing, delivering the tubular housing by means of a catheter transatrially, transseptally, transfemorally or transapically to the mitral valve of the heart, anchoring the support structure to the native mitral valve.
BRIEF DESCRIPTION OF THE DRAWINGS
[0065] FIG. 1 is a schematic illustration of a human heart,
[0066] FIGS. 2-8 are schematic illustrations of the consecutive steps of deploying a mitral valve implant in a first embodiment,
[0067] FIG. 9 is a schematic illustration of a second embodiment of a mitral valve,
[0068] FIG. 10 is a schematic illustration of an alternative way of a mitral valve implant deployment,
[0069] FIG. 11 is a schematic illustration of the first embodiment of the mitral valve folded so as to be deployable by means of a catheter,
[0070] FIG. 12 is a top view of the first embodiment of the mitral valve in a deployed condition,
[0071] FIG. 13 is a side view of the first embodiment of the mitral valve in a deployed condition,
[0072] FIGS. 14-19 are side views of the first embodiment of the mitral valve in different steps of the deployment procedure.
DETAILED DESCRIPTION
[0073] Aspects of the present invention are disclosed in the following description and related figures directed to specific embodiments of the invention. Those skilled in the art will recognize that alternate embodiments may be devised without departing from the spirit or the scope of the claims. Additionally, well-known elements of exemplary embodiments of the invention will not be described in detail or will be omitted so as not to obscure the relevant details of the invention.
[0074] It should be understood that the described embodiments are not necessarily to be construed as preferred or advantageous over other embodiments. Moreover, the terms “embodiments of the invention”, “embodiments” or “invention” do not require that all embodiments of the invention include the discussed feature, advantage or mode of operation.
[0075] In FIG. 1 is a schematic illustration of a human heart 1 comprising the right ventricle 2 , the right atrium 3 , the left ventricle 4 and the left atrium 5 . The septum 6 divides the heart 1 in a right and a left section. The mitral valve 7 allows the blood to flow from the left atrium 5 into the left ventricle 4 . The tricuspid valve 8 is located between the right atrium 3 and the right ventricle 2 . The ascending aorta 9 originates at the orifice of the aortic valve 10 . The mitral valve 7 comprises an anterior leaflet and a posterior leaflet that are anchored within the left ventricular cavity by chordae tendineae 11 , which prevent the valve 7 from prolapsing into the left atrium 5 .
[0076] The mitral valve implant of the invention is configured to be deployed to the heart transcatheterally. In particular, the implant can be delivered to the heart by means of a catheter transatrially, i.e. through the left atrium of the heart, transseptally, i.e. through the septum 6 of the heart as depicted by line 12 , transapically, i.e. through the apex of the heart as depicted by line 13 , or through the ascending aorta 9 as depicted by line 14 .
[0077] During the implant procedure a balloon 15 is placed into the orifice of the mitral valve 7 , which is inflated during systole and deflated during diastole to minimize regurgitant volume flow and to prevent severe inflow into the pulmonary veins.
[0078] In FIG. 2 the mitral valve 7 is shown in more detail. The mitral valve 7 comprises an annulus 16 , from which the anterior leaflet 17 and the posterior leaflet 18 emerge. In a pathological condition of the mitral valve 7 , the annulus 16 can be dilated so that the anterior leaflet 17 and the posterior leaflet 18 fail to coapt and do not provide a tight seal between the left ventricle 4 and the left atrium 5 during systole.
[0079] The catheter to deliver the implant to the heart is denoted with reference number 19 and carries a tubular housing 20 on its free end, in which the implant is arranged in a compacted, in particular folded state during delivery. The catheter 19 comprises an inner movable member 21 in the form of a hollow cylinder. The inner movable member 21 is guided to be movable in an axial direction relative to the housing 20 and comprises a chamfered tip 23 . As can be seen in FIG. 2 the inner movable member 21 has been advanced in the direction or arrow 24 to penetrate the annulus 16 from below, i.e. from the left ventricle 4 , so that the tip 23 of the inner movable member 21 protrudes into the left atrium 5 . The position of the penetration point preferably is arranged between the two papillary muscles of the subvalvular apparatus of the posterior leaflet. To find the exact penetration position, the positioning of the chamfered tip 23 is facilitated by a steerable catheter element with electrodes.
[0080] The inner movable member 21 has an opening at its distal end in order to deploy the implant to the implantation site. In FIG. 2 a part of the upper support element 22 of the implant projects from the movable member 21 .
[0081] FIG. 3 illustrates the deployment of the upper support element 22 of the support structure. The upper support element 22 has been pushed forward according to arrow 25 so that it completely exits the movable member 21 . The upper support element 22 comprises a straight base section 26 and side arms 27 and 28 . The side arms 27 , 28 and the base section 26 are made from at least one wire, wherein a memory-shape material, such as Nitinol is preferred. When housed in the inner movable member 21 , the side arms 27 and 28 are folded down and extend parallel to the straight base section 26 . Once deployed from the inner movable member 26 , the side arms 27 , 28 fold out to the side and up, so that they come to lie in a common plane that encloses an angle α of 70-90° with the straight base section 26 .
[0082] The arms 27 , 28 are shaped to substantially conform to the curvature of the annulus 16 . In the embodiment according to FIGS. 2 to 8 the arms 27 , 28 extend only over a part of the circumference of annulus 16 . In particular, the arms 27 , 28 of the upper support element extend only over the segment of the annulus 16 , from which the posterior leaflet 18 emerges.
[0083] The arms 27 , 28 of the upper support element 22 are received in a cavity of a jacket 29 surrounding the arms 27 , 28 . The jacket 29 is integral with an artificial leaflet 30 and is made of a biocompatible material, such as polyethylene or polyurethane, polyfluorethylen (Goretex®) or from natural tissue such as heterologic pericardium. The artificial leaflet comprises a first section immediately adjacent the jacket 29 , in which the artificial leaflet 30 comprises a plurality of cushion-like embossments 31 mimicking the natural shape of the scallops (p1,p2,p3) of the native posterior leaflet 18 . Further, the artificial leaflet 30 comprises an inferior section 32 that is planar and does not comprise a cavity. Further, the inferior section 32 carries a strap 33 that will be described later in more detail.
[0084] Turning now to FIG. 4 , the movable member 21 together with the upper support element 22 has been retracted according to arrow 34 so that the tip 23 of the movable member 21 is positioned below the annulus 16 and the upper support element 22 is seated against the upper surface of the annulus 16 . In doing so, the straight section 26 of the upper support element 22 is retracted with such a pulling force that the angle between the common plane of the arms 27 , 28 and the straight base enlarged to approximately 90°. Thereby, a constant pre-load is applied onto the upper surface of the annulus 16 . Upon retraction of the upper support element 22 the artificial leaflet 30 is seated onto the native posterior leaflet 18 .
[0085] In the illustration according to FIG. 5 the lower support element 35 has been deployed from the movable member 21 via the distal opening of the same. The lower support element 35 comprises two arms 36 , 37 that have been folded to the side and up, so that they come to lie in a common plane and get seated to the lower surface of the annulus 16 , i.e. the surface of the annulus 16 that faces the left ventricle 4 . The arms 36 , 37 are shaped to substantially conform to the curvature of the annulus 16 . In the embodiment according to FIGS. 2 to 8 the arms 36 , 37 extend only over a part of the circumference of annulus 16 . In particular, the arms 36 , 37 of the lower support element 35 extend only over the segment of the annulus 16 , from which the posterior leaflet 18 emerges.
[0086] The arms 36 , 37 of the lower support element 35 are received in a cavity of a jacket 38 surrounding the arms 36 , 37 .
[0087] FIG. 6 corresponds to the FIG. 5 , but the jackets 29 and 38 as well as the first section of the artificial leaflet 30 (comprising the cushion-like embossments 31 ) have been “inflated” or expanded. In doing so the annulus 16 is squeezed from above and from below between the jacket 29 and the jacket 38 thereby fixing the position of the support structure. Further, the inflation of the jacket 29 results in a radial expansion along the arms 27 , 28 so that a radical bracing force is achieved between the outer circumference of the jacket 29 and an inner circumference of the annulus 16 .
[0088] The inflation of the first section of the artificial leaflet 30 results in that this section receives a desired 3D-shape including a desired 3D surface shape of the coaptation surface in order to improve coaptation with the native anterior leaflet 17 .
[0089] The inflation of the jackets 29 and 38 as well as of the first section of the artificial leaflet 30 may be achieved in different ways. As an example, the cavities can be filled with a viscous fluid or a gel. The viscous fluid or the gel can be delivered to the cavities through a lumen of the catheter 19 . Alternatively, the cavities can be filled with a pre-polymer before the implant is deployed to the heart and a chemical reaction of the pre-polymer can be induced in-situ so as to produce a foamy or porous structure thereby expanding the volume of the respective cavity. Preferably, the amount of filling material or pre-polymer to be inserted into the cavity is calculated according to the e-module of the filling material and the expected and preferred cushion size.
[0090] Particularly preferable is the use of a gel as a filling material for the cavity of the artificial leaflet. The gel allows an adaption of the 3D shape of the artificial leaflet at each closing of the valve. In practice, an optimization of the shape is obtained already a few closing cycles after starting of the operation of the implant. In this way the coaptation of the artificial leaflet with the native anterior leaflet is substantially improved.
[0091] The inflation of the artificial leaflet 30 results in a dislocation of the native posterior leaflet 18 such that the native posterior leaflet 18 is moved closer to the wall 41 of the heart.
[0092] The cavity of jacket 29 may be separate from the cavity of the artificial leaflet 30 . Alternatively, the cavity of the artificial leaflet 30 and the cavity of the jacket 29 may be connected to each other to form a single cavity.
[0093] FIG. 7 shows the deployment of a leash-like cord or wire 39 . The cord or wire 39 has a hook at its free end, which serves to catch and engage with the strap 33 . In this way, the inferior region of the artificial leaflet 30 is held in a position so as to prevent prolapsing of the artificial leaflet 30 into the left atrium 5 . Alternatively, the chordae of the native leaflet, if still functioning, may be use to support the artificial leaflet motion and prevent prolapsing of the artificial leaflet 30 into the left atrium 5 . Another alternative is to embed are more rigid part into the artificial leaflet to prevent prolapse.
[0094] FIG. 8 shows that the degree of retention of the inferior end region of the artificial leaflet 30 can be controlled by varying the length of the cord or wire 39 . The length of the cord or wire 39 may be controlled by imaging techniques. In the embodiment shown in FIG. 8 , the cord or wire 39 has been completely retracted, so that a maximum of retention force is applied. Further, the catheter 19 has been disconnected form the cylindrical housing 20 of the support structure.
[0095] The retention of the inferior end region of the artificial leaflet 30 safeguards the mobility of the anterior leaflet 17 and avoids a systolic anterior movement.
[0096] In FIG. 9 an alternative embodiment is illustrated, wherein the upper support element 22 comprises a circular wire 40 and a jacket 29 surrounding the circular wire 40 , both extending along the entire length of the annulus 16 . As with the embodiment according to FIGS. 1 to 8 , the cavity of the upper support element 22 may be filled with a viscous fluid or a gel.
[0097] FIG. 10 shows an alternative way of advancing the catheter tip so as to penetrate the annulus 16 from below. A separate anchor 43 is introduced into the heart from above, i.e. form the left atrium, which is connected to the distal end of the catheter 19 by means of a hook mechanism 42 , in order to be able to pull instead of push the catheter 19 to penetrate the annulus 16 .
[0098] The foregoing description and accompanying figures illustrate the principles, preferred embodiments and modes of operation of the invention. However, the invention should not be construed as being limited to the particular embodiments discussed above. Additional variations of the embodiments discussed above will be appreciated by those skilled in the art.
[0099] Therefore, the above-described embodiments should be regarded as illustrative rather than restrictive. Accordingly, it should be appreciated that variations to those embodiments can be made by those skilled in the art without departing from the scope of the invention as defined by the following claims. | The invention relates to an implant and a method for improving coaptation of an atrioventricular valve, the atrioventricular valve having a native first leaflet, a native second leaflet and an annulus. The implant comprises a support structure and a flexible artificial leaflet structure mounted to the support structure and shaped to coapt with the native second leaflet. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a rotation sensor for detecting rotation of a rotating body, which is used in, for example, an engine or a transmission of an automobile.
2. Description of the Related Art
FIG. 44 is a front sectional view illustrating a related-art rotation sensor 1 disclosed in Japanese Patent Application Laid-open No. 2012-2564 ( FIGS. 1, 2, and 4 to 12 ).
The rotation sensor 1 is inserted into an opening of a housing 10 including a rotary shaft 11 housed therein so as to be mounted to the housing 10 .
A plurality of convex portions 12 made of a ferromagnetic material such as iron are provided on an outer circumferential surface of the rotary shaft 11 as a rotating body such as a connecting shaft connected to a crankshaft of an engine or the crankshaft so as to be arranged at intervals in a circumferential direction of the rotary shaft 11 .
The rotation sensor 1 for detecting rotation of the rotary shaft 11 includes a case 2 , a pair of lead frames 3 X and 3 Y, a magnetic detection section 7 , an internal filling resin 8 , and an exterior resin 9 . The case 2 is provided at a distance from a surface of the convex portion 12 , and includes a bottom surface portion 2 a and a side surface portion 2 b . The side surface portion 2 b defines an internal space having an opening 2 c in cooperation with the bottom surface portion 2 a . One end of each of the lead frames 3 X and 3 Y is inserted into the internal space of the case 2 through the opening 2 c , whereas another end thereof protrudes externally from the case 2 . The magnetic detection section 7 is provided to distal ends of the lead frames 3 X and 3 Y so as to be electrically connected to the lead frames 3 X and 3 Y. The internal filling resin 8 is filled into the internal space of the case 2 . The exterior resin 9 covers the opening 2 c of the case 2 .
A positioning portion 3 Xe of the lead frame 3 X and a positioning portion 3 Ye of the lead frame 3 Y are held in contact with an opening circumferential edge portion 2 d of the case 2 . In this manner, a height position of the magnetic detection section 7 inside the case 2 is determined.
The magnetic detection section 7 includes an in-sensor magnet 5 and an integrated circuit (IC) 4 that is magnetic detection means. The IC 4 includes a detection element such as a hall element and a signal processing circuit.
In the rotation sensor 1 , the IC 4 generates a signal in accordance with a change in magnetic field of the in-sensor magnet 5 by the rotation of the rotary shaft 11 having the convex portions 12 made of the magnetic material.
The above-mentioned rotation sensor 1 is manufactured in the following steps as shown in FIGS. 4 to 10 of Japanese Patent Application Laid-open No. 2012-2654.
First, a lead-frame coupled body including the lead frames 3 X and 3 Y and a coupling portion for connecting the lead frames 3 X and 3 Y to each other is made of a metal plate having a rectangular shape.
Next, the magnetic detection section 7 is provided to an end of the lead-frame coupled body (first step).
Thereafter, the lead-frame coupled body and the magnetic detection section 7 are inserted into the internal space of the case 2 through the opening 2 c of the case 2 (second step).
Thereafter, the internal space of the case 2 is filled with the internal filling resin 8 that is a mold resin (third step).
Next, after the internal filling resin 8 is cured, the coupling portion is removed so as to separate the lead frames 3 X and 3 Y from each other (fourth step).
Finally, a semi-product including the lead frames 3 X and 3 Y and the magnetic detection section 7 that are assembled inside the case 2 is placed inside a die (not shown) for the exterior resin 9 . By molding, a connector housing for external connection and a sensor exterior part are formed on the case 2 , and the opening 2 c of the case 2 is covered with the exterior resin 9 .
In the related-art rotation sensor 1 , the internal space of the case 2 is filled with a large amount of the internal filling resin 8 . A material to be used as the internal filling resin 8 is generally an epoxy resin that is expensive. Thus, there is a problem in that manufacturing costs increase.
Further, in the manufacturing of the rotation sensor 1 , most attention needs to be paid to the arrangement of the magnetic detection section 7 in a predetermined dimensional position. In handling, for inserting the magnetic detection section 7 into the case 2 , the pair of lead frames 3 X and 3 Y or the magnetic detection section 7 is inevitably required to be held. Therefore, particular attention is required to be paid so that the lead frames 3 X and 3 Y are not deformed. Therefore, there is another problem in that workability is low.
SUMMARY OF THE INVENTION
The present invention has been made to solve the problems described above, and has an object to provide a rotation sensor capable of reducing manufacturing costs and improving workability.
According to one embodiment of the present invention, there is provided a rotation sensor for detecting rotation of a rotating body, including:
a case including:
a bottom surface portion provided at a distance from a surface of the rotating body; and a side surface portion connected to the bottom surface portion so as to define a hollow internal space in cooperation with the bottom surface portion,
the case having an opening spatially connected to the hollow internal space, which is formed in the side surface portion on a side opposite to the bottom surface portion;
a plurality of lead frames respectively having distal ends inserted into the case through the opening;
a magnetic detection section provided to the distal ends of the plurality of lead frames arranged in parallel, for detecting a change in magnetic field of a magnetic body provided to the rotating body;
a spacer provided between the plurality of lead frames and the side surface portion so as to be held in contact with an internal wall surface of the side surface portion; and
an internal filling resin for filling a space portion of the hollow internal space except for the spacer, the magnetic detection section, and the plurality of lead frames.
According to the rotation sensor of the one embodiment of the present invention, the spacer is provided between the lead frame and the side surface portion so as to be held in contact with the inner wall surface of the side surface portion of the case. Therefore, the amount of use of the expensive internal filling resin can be reduced, thereby reducing the manufacturing costs.
Further, when inserting the magnetic detection section into the case, the magnetic detection section is inserted into the case with the lead frames being fixed to the spacer. As a result, deformation of the lead frames is reduced so as to improve the workability.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front sectional view illustrating the rotation sensor according to a first embodiment of the present invention.
FIG. 2 is a sectional view of FIG. 1 , as viewed in a direction of the arrow II.
FIG. 3 is a front sectional view illustrating a rotation sensor according to a second embodiment of the present invention.
FIG. 4 is a sectional view of FIG. 3 , as viewed in a direction of the arrow IV.
FIG. 5 is a front sectional view illustrating a rotation sensor according to a third embodiment of the present invention.
FIG. 6 is a sectional view of FIG. 5 , as viewed in a direction of the arrow VI.
FIG. 7 is a front sectional view illustrating a rotation sensor according to a fourth embodiment of the present invention.
FIG. 8 is a sectional view of FIG. 7 , as viewed in a direction of the arrow VIII.
FIG. 9 is a front sectional view illustrating a rotation sensor according to a fifth embodiment of the present invention.
FIG. 10 is a sectional view of FIG. 9 , as viewed in a direction of the arrow X.
FIG. 11 is a front sectional view illustrating a rotation sensor according to a sixth embodiment of the present invention.
FIG. 12 is a sectional view of FIG. 11 , as viewed in a direction of the arrow XII.
FIG. 13 is a front sectional view illustrating a rotation sensor according to a seventh embodiment of the present invention.
FIG. 14 is a sectional view of FIG. 13 , as viewed in a direction of the arrow XIV.
FIG. 15 is a front sectional view illustrating a rotation sensor according to an eighth embodiment of the present invention.
FIG. 16 is a sectional view of FIG. 15 , as viewed in a direction of the arrow XVI.
FIG. 17 is a front sectional view illustrating a rotation sensor 1 according to a ninth embodiment of the present invention.
FIG. 18 is a sectional view of FIG. 17 as viewed in a direction of the arrow XVIII.
FIG. 19 is a sectional view taken along the line A-A in FIG. 17 , as viewed in a direction of the arrows.
FIG. 20 is a front sectional view illustrating a rotation sensor according to a tenth embodiment of the present invention.
FIG. 21 is a sectional view of FIG. 20 , as viewed in a direction of the arrow XXI.
FIG. 22 is a side sectional view illustrating a modification of a rotation sensor according to a tenth embodiment of the present invention.
FIG. 23 is a front sectional view illustrating a rotation sensor according to an eleventh embodiment of the present invention.
FIG. 24 is a sectional view of FIG. 23 as viewed in a direction of the arrow XXIV.
FIG. 25 is a sectional view taken along the line B-B in FIG. 23 , as viewed in a direction of the arrows.
FIG. 26 is a sectional view taken along the line C-C in FIG. 24 , as viewed in a direction of the arrows.
FIG. 27 is an explanatory view explaining a first step of manufacturing process of a rotation sensor according to a ninth embodiment ( FIG. 17 ) of the present invention.
FIG. 28 is a sectional view of FIG. 27 as viewed in a direction of the arrow XXVIII.
FIG. 29 is an explanatory view explaining a next step (a second step) of manufacturing process of a rotation sensor shown in FIG. 27 .
FIG. 30 is a sectional view of FIG. 29 as viewed in a direction of the arrow
XXX.
FIG. 31 is an explanatory view explaining a next step (a second step) of manufacturing process of a rotation sensor shown in FIG. 27 .
FIG. 32 is a sectional view of FIG. 31 as viewed in the direction of the arrow XXXII.
FIG. 33 is an explanatory view explaining a procedure assembling a spacer to a lead-frame in a second step.
FIG. 34 is an explanatory view explaining a procedure assembling a spacer to a lead-frame in a second step.
FIG. 35 is an explanatory view explaining a procedure assembling a spacer to a lead-frame in a second step.
FIG. 36 is an explanatory view explaining a procedure assembling a spacer to a lead-frame in a second step.
FIG. 37 is an explanatory view explaining a procedure assembling a spacer to a lead-frame in a second step.
FIG. 38 is a sectional view of FIG. 37 as viewed in a direction of the arrow XXXVIII.
FIG. 39 is an explanatory view explaining a next step (a third step) of manufacturing process of a rotation sensor shown in FIG. 29 .
FIG. 40 is an explanatory view explaining a third step.
FIG. 41 is a sectional view of FIG. 40 as viewed in a direction of the arrow XLI.
FIG. 42 is an explanatory view explaining a next step (a forth step) of manufacturing process of a rotation sensor shown in FIG. 39 .
FIG. 43 is a sectional view of FIG. 42 as viewed in a direction of the arrow XLIII.
FIG. 44 is a front sectional view illustrating a related-art rotation sensor.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Now, a rotation sensor 1 according to each of embodiments of the present invention is described. In the drawings including FIG. 44 illustrating the related art, the same or corresponding members and parts are denoted by the same reference symbols for description.
First Embodiment
FIG. 1 is a front sectional view illustrating the rotation sensor 1 according to a first embodiment of the present invention, and FIG. 2 is a sectional view of FIG. 1 , as viewed in a direction of the arrow II.
In the rotation sensor 1 of the first embodiment, a magnetic detection section 7 is entirely covered with an internal filling resin 8 in an internal space of a case 2 with a closed end, which has a circular sectional shape. Above the magnetic detection section 7 , a spacer 13 is provided on one side of the pair of lead frames 3 X and 3 Y. The pair of lead frames 3 X and 3 Y is covered with an exterior resin 9 on another side.
The case 2 , the exterior resin 9 , and the spacer 13 are made of a polyphenylenesulfide (PPS) resin or a polybutylene terephthalate (PBT) resin. The internal filling resin 8 is an epoxy resin.
The remaining configuration is the same as that of the related-art rotation sensor 1 illustrated in FIG. 44 .
In the rotation sensor 1 according to the first embodiment, the lead frames 3 X and 3 Y are interposed between the spacer 13 and the exterior resin 9 . As compared with the related-art rotation sensor 1 in which the internal filling resin 8 is provided around the lead frames 3 X and 3 Y, the amount of the internal filling resin 8 can be significantly reduced.
As a result, the amount of use of the internal filling resin 8 that is an expensive epoxy resin can be significantly reduced. Thus, manufacturing costs can be lowered.
Further, when inserting the magnetic detection section 7 into the case 2 , the magnetic detection section 7 is inserted into the case 2 with the lead frames 3 X and 3 Y being fixed to the spacer 13 . As a result, deformation of the lead frames 3 X and 3 Y is reduced to improve workability.
Second Embodiment
FIG. 3 is a front sectional view illustrating a rotation sensor 1 according to a second embodiment of the present invention, and FIG. 4 is a sectional view of FIG. 3 , as viewed in a direction of the arrow IV.
The rotation sensor 1 of the second embodiments includes three lead frames 3 X, 3 Y, and 3 Z. Among the three lead frames 3 X, 3 Y, and 3 Z, a positioning portion 3 Xe of the lead frame 3 X and a positioning portion 3 Ye of the lead frame 3 Y are held in contact with an opening circumferential edge portion 2 d of the case 2 . As a result, a height position of the magnetic detection section 7 inside the case 2 is determined.
The lead frames 3 X, 3 Y, and 3 Z are interposed between spacers 13 X and 13 Y so as to be opposed to each other. Each of the spacers 13 X and 13 Y has a semi-cylindrical shape obtained by cutting a cylinder along an axial direction. Each of the spacers 13 X and 13 Y is held in surface contact with an inner wall surface of a side surface portion 2 b of the case 2 .
Also in the rotation sensor 1 of the second embodiment, the amount of the internal filling resin 8 can be reduced. As a result, the manufacturing costs are reduced.
Further, when inserting the magnetic detection section 7 into the case 2 , the magnetic detection section 7 is inserted into the case 2 so that the lead frames 3 X, 3 Y, and 3 Z are interposed between the spacers 13 X and 13 Y. As a result, as compared with the rotation sensor 1 of the first embodiment, the deformation of the lead frames 3 X, 3 Y, and 3 Z is further reduced to further improve the workability.
Third Embodiment
FIG. 5 is a front sectional view illustrating a rotation sensor 1 according to a third embodiment of the present invention, and FIG. 6 is a sectional view of FIG. 5 , as viewed in a direction of the arrow VI.
In the rotation sensor 1 of the third embodiment, the opening circumferential edge portion 2 d of the case 2 , with which the positioning portion 3 Xe of the lead frame 3 X and the positioning portion 3 Ye of the lead frame 3 Y in the height direction are held in contact, is provided closer to a bottom surface portion 2 a than an opening 2 c of the case 2 , as compared with the rotation sensors 1 of the first and second embodiments.
Therefore, at the time when the magnetic detection section 7 is buried with the internal filling resin 8 inside the case 2 , a dimension E (not shown) from a contact surface between the opening circumferential edge portion 2 d of the case 2 and the positioning portions 3 Xe and 3 Ye to an integrated circuit (IC) 4 of the magnetic detection section 7 mounted to the lead frames 3 X, 3 Y, and 3 Z is determined with high accuracy.
Specifically, an insertion depth dimension of the lead frames 3 X, 3 Y, and 3 Z and the magnetic detection section 7 (IC 4 ) in the case 2 is kept to the predetermined dimension by the positioning portions 3 Xe and 3 Ye. In this state, the lead frames 3 X, 3 Y, and 3 Z and the magnetic detection section 7 are fixed with the internal filling resin 8 .
Fourth Embodiment
FIG. 7 is a front sectional view illustrating a rotation sensor 1 according to a fourth embodiment of the present invention, and FIG. 8 is a sectional view of FIG. 7 , as viewed in a direction of the arrow VIII.
The rotation sensor 1 of the fourth embodiment, fitting means for fitting the spacer 13 and the magnetic detection section 7 to each other is provided to the spacer 13 and the magnetic detection section 7 .
The fitting means includes a fitting portion 7 X formed on the magnetic detection section 7 and a magnetic detection section supporting portion 13 a having a convex shape to be fitted into the fitting portion 7 X.
The remaining configuration is the same as that of the rotation sensor 1 of the third embodiment.
In the rotation sensor 1 of the fourth embodiment, the spacer 13 supports the magnetic detection section 7 together with the lead frames 3 X, 3 Y, and 3 Z by the fitting of the magnetic detection section supporting portion 13 a of the spacer 13 into the fitting portion 7 X. Thus, the deformation of the lead frames 3 X, 3 Y, and 3 Z is further reduced when the magnetic detection section 7 is inserted into the case 2 . As a result, the magnetic detection section 7 is installed in a predetermined position with high accuracy.
Fifth Embodiment
FIG. 9 is a front sectional view illustrating a rotation sensor 1 according to a fifth embodiment of the present invention, and FIG. 10 is a sectional view of FIG. 9 , as viewed in a direction of the arrow X.
In the rotation sensor 1 of the fifth embodiment, ribs 13 b are provided on a plane portion of the spacer 13 having a semi-circular sectional shape so as to be located close to the magnetic detection section 7 . The ribs 13 b having distal ends extend into gaps between the adjacent lead frames 3 X, 3 Y, and 3 Z.
The remaining configuration is the same as that of the rotation sensor 1 of the fourth embodiment.
In the rotation sensor 1 of the fifth embodiment, the ribs 13 b are provided in the gaps between the adjacent lead frames 3 X, 3 Y, and 3 Z. Thus, the ribs 13 b function as partition walls so that electrical short-circuit is prevented from occurring between the lead frames 3 X, 3 Y, and 3 Z when the lead frames 3 X, 3 Y, and 3 Z are deformed.
Sixth Embodiment
FIG. 11 is a front sectional view illustrating a rotation sensor 1 according to a sixth embodiment of the present invention, and FIG. 12 is a sectional view of FIG. 11 , as viewed in a direction of the arrow XII.
In the rotation sensor 1 of the sixth embodiment, positioning pins 13 c are provided to a plane portion of the spacer 13 having a semi-circular sectional shape. Positioning pins 13 c are provided so as to interpose the lead frames 3 X, 3 Y, and 3 Z and be held in contact with both end surfaces of the lead frames 3 X, 3 Y, and 3 Z, respectively.
The remaining configuration is the same as that of the rotation sensor 1 of the fourth embodiment.
In the case of the rotation sensor 1 of the sixth embodiment, the electrical short-circuit can be prevented from occurring between the lead frames 3 X, 3 Y, and 3 Z by the positioning pins 13 c when the lead frames 3 X, 3 Y, and 3 Z are deformed, as in the case of the rotation sensor 1 of the fifth embodiment.
Seventh Embodiment
FIG. 13 is a front sectional view illustrating a rotation sensor 1 according to a seventh embodiment of the present invention, and FIG. 14 is a sectional view of FIG. 13 , as viewed in a direction of the arrow XIV.
In the rotation sensor 1 of the seventh embodiment, positioning holes 3 Xf, 3 Zf, and 3 Yf are respectively formed in the lead frames 3 X, 3 Y, and 3 Z. Positioning pins 13 d are provided to a plane portion of the spacer 13 having a semi-circular sectional shape so as to be respectively opposed to the positioning holes 3 Xf, 3 Zf, and 3 Yz.
The remaining configuration is the same as that of the rotation sensor 1 of the fourth embodiment.
According to the rotation sensor 1 of the seventh embodiment, the positioning pins 13 d are pressed into the positioning holes 3 Xf, 3 Zf, and 3 Yf of the lead frames 3 X, 3 Y, and 3 Z, thereby integrating the lead frames 3 X, 3 Y, and 3 Z with the spacer 13 . As a result, the deformation of the lead frames 3 X, 3 Y, and 3 Z is reduced when the magnetic detection section 7 is inserted into the case 2 . As a result, the magnetic detection section 7 is installed in a predetermined position with higher accuracy.
Eighth Embodiment
FIG. 15 is a front sectional view illustrating a rotation sensor 1 according to an eighth embodiment of the present invention, and FIG. 16 is a sectional view of FIG. 15 , as viewed in a direction of the arrow XVI.
In the rotation sensor 1 of the eighth embodiment, the lead frames 3 X, 3 Y, and 3 Z are interposed between the spacers 13 X and 13 Y. Each of the spacers 13 X and 13 Y has a semi-cylindrical shape obtained by cutting a cylinder along the axial direction. The spacers 13 X and 13 Y are held in surface contact with the inner wall surface of the side surface portion 2 b of the case 2 , which has a circular sectional shape.
Three positioning pins 13 Xd are provided to the spacer 13 X. Positioning holes 13 Yd are formed in the spacer 13 Y so as to be opposed to the positioning pins 13 Xd.
The positioning holes 3 Xf, 3 Yf, and 3 Zf are respectively formed through the lead frames 3 X, 3 Y, and 3 Z.
When the lead frames 3 X, 3 Y, and 3 Z are interposed between the spacers 13 X and 13 Y, the positioning pins 13 Xd of the spacer 13 X are respectively fitted into the positioning holes 13 Yd of the spacer 13 Y through the positioning holes 3 Xf, 3 Yf, and 3 Zf of the lead frames 3 X, 3 Y, and 3 Z.
The remaining configuration is the same as that of the rotation sensor 1 of the fourth embodiment.
In the rotation sensor 1 of the eighth embodiment, the lead frames 3 X, 3 Y, and 3 Z are interposed between the spacers 13 X and 13 Y and are integrated with the spacers 13 X and 13 Y.
Therefore, as illustrated in FIG. 27 , the lead frames 3 X, 3 Y, and 3 Z are formed by cutting coupling portions 3 Za of a lead-frame coupled body 3 ZZ. The coupling portions 3 Za can be cut in the integrated state described above.
Specifically, in an assembly step for the rotation sensor 1 , when the lead frames 3 X, 3 Y, and 3 Z are assembled to the spacer 13 X, the lead frames 3 X, 3 Y, and 3 Z connected through the coupling portions 3 Za are first assembled to the spacer 13 X as a single component. Thereafter, the coupling portions 3 Za are cut. In this manner, productivity is significantly improved.
Further, a semi-product, in which the lead frames 3 X, 3 Y, and 3 Z are interposed between the spacers 13 X and 13 Y so as to integrate the lead frames 3 X, 3 Y, and 3 Z, the spacers 13 X and 13 Y, and the magnetic detection section 7 with each other, can be handled as a single component. Thus, handling properties are improved in assembly. At the same time, the deformation of the lead frames 3 X, 3 Y, and 3 Z is reduced. As a result, the magnetic detection section 7 is installed in a predetermined position with higher accuracy.
Ninth Embodiment
FIG. 17 is a front sectional view illustrating a rotation sensor 1 according to a ninth embodiment of the present invention, FIG. 18 is a sectional view of FIG. 17 as viewed in a direction of the arrow XVIII, and FIG. 19 is a sectional view taken along the line A-A in FIG. 17 , as viewed in a direction of the arrows.
In the rotation sensor 1 of the ninth embodiment, spacer concave-side fitting portions 13 XeL and 13 XeR are formed on the spacer 13 X. Spacer convex-side fitting portions 13 YeL and 13 YeR to be fitted into the spacer convex-side fitting portions 13 XeL and 13 XeR are formed on the spacer 13 Y.
The letter “L” in the reference symbols 13 XeL, 13 XeR, 13 YeL, and 13 YeR indicates the spacer concave-side fitting portion and the spacer convex-side fitting portion that are provided on the left in FIG. 19 , whereas the letter “R” indicates the spacer concave-side fitting portion and the spacer convex-side fitting portion that are provided on the right.
A lead-frame interposing portion 3 Xg, which is provided on the side closer to the adjacent lead frame 3 Z so as to project toward the spacer 13 X, is formed on the lead frame 3 X. A lead-frame interposing portion 3 Yg, which is provided on the side closer to the adjacent lead frame 3 Z so as to project toward the spacer 13 X, is formed on the lead frame 3 Y. Lead-frame interposing portions 3 Zgx and 3 Zgy are formed on the spacer 3 Z so as to project toward the spacer 13 X. The lead-frame interposing portion 3 Zgx is provided on the side closer to the adjacent lead frame 3 X, whereas the lead-frame interposing portion 3 Zgy is provided on the side closer to the adjacent lead frame 3 Y.
When the lead frames 3 X, 3 Y, and 3 Z are interposed between the spacers 13 X and 13 Y, the spacer convex-side fitting portions 13 YeL and 13 YeR are fitted into the spacer concave-side fitting portions 13 XeL and 13 XeR through the lead-frame interposing portions 3 Xg, 3 Yg, 3 Zgx, and 3 Zgy. In this manner, the lead frames 3 X, 3 Y, and 3 Z are integrated with the spacers 13 X and 13 Y.
The remaining configuration is the same as that of the rotation sensor 1 of the fourth embodiment.
In an x-direction in FIG. 19 , the following expression is satisfied for dimensions of the spacer concave-side fitting portion 13 XeL, the lead-frame interposing portion 3 Xg, the spacer convex-side fitting portion 13 YeL, and the lead-frame interposing portion 3 Zgx.
13 XeL≧ 3 Xg+ 13 YeL+ 3 ZgX
Further, similarly, the following expression is satisfied for dimensions of the spacer concave-side fitting portion 13 XeR, the lead-frame interposing portion 3 Yg, the spacer concave-side fitting portion 13 XeR, and the lead-frame interposing portion 3 Zgy.
13 XeR≧ 3 Yg+ 13 XeR+ 3 Zgy
According to the rotation sensor 1 of the ninth embodiment, a semi-product, in which the lead frames 3 X, 3 Y, and 3 Z are interposed between the spacers 13 X and 13 Y so as to integrate the lead frames 3 X, 3 Y, and 3 Z, the spacers 13 X and 13 Y, and the magnetic detection section 7 with each other, can be handled as a single component as in the case of the rotation sensor 1 of the eighth embodiment. Thus, the handling properties are improved in assembly. At the same time, the deformation of the lead frames 3 X, 3 Y, and 3 Z is reduced. As a result, the magnetic detection section 7 is installed in a predetermined position with higher accuracy.
Further, after the lead frames 3 X, 3 Y, and 3 Z are assembled to the spacer 13 X or 13 Y in a state in which the adjacent lead frames 3 X, 3 Y, and 3 Z are connected in advance through connecting portions (not shown) for the lead-frame interposing portions 3 Xg, 3 Zgx, 3 Zgy, and 3 Yg as a single component, the connecting portions are cut. In this manner, the productivity can also be improved.
Tenth Embodiment
FIG. 20 is a front sectional view illustrating a rotation sensor 1 according to a tenth embodiment of the present invention, and FIG. 21 is a sectional view of FIG. 20 , as viewed in a direction of the arrow XXI.
In the rotation sensor 1 of the tenth embodiment, positional alignment portions for positional alignment between the case 2 and the spacer 13 Y are provided between the case 2 and the spacer 13 Y.
The positional alignment portions include a positional alignment convex portion 13 Yf and a positional alignment concave portion 2 j . The positional alignment convex portion 13 Yf is provided to a portion of an upper outer circumferential portion of the spacer 13 Y so as to project radially outward. The positional alignment concave portion 2 j , into which the positional alignment convex portion 13 Yf is fitted, is formed on the side surface portion 2 b of the case 2 .
The remaining configuration is the same as that of the rotation sensor 1 of the ninth embodiment.
According to the rotation sensor 1 of this embodiment, even when the inner wall of the case 2 has a cylindrical shape and the lead frames 3 X, 3 Y, and 3 Z are located in the center of the case 2 , a direction of assembly of the magnetic detection section 7 is automatically determined by fitting the positional alignment convex portion 13 Yf into the positional alignment concave portion 2 j of the case 2 when the semi-product, in which the lead frames 3 X, 3 Y, and 3 Z are interposed between the spacers 13 X and 13 Y so as to be integrated with each other, is assembled into the case 2 .
Alternatively, as illustrated in FIG. 22 , the positional alignment convex portion 2 j may be formed on the case 2 , while the positional alignment concave portion 13 Yf, into which the positional alignment convex portion 2 j is to be fitted, may be formed on the spacer 13 Y.
Eleventh Embodiment
FIG. 23 is a front sectional view illustrating a rotation sensor 1 according to an eleventh embodiment of the present invention, FIG. 24 is a sectional view of FIG. 23 as viewed in a direction of the arrow XXIV, FIG. 25 is a sectional view taken along the line B-B in FIG. 23 , as viewed in a direction of the arrows, and FIG. 26 is a sectional view taken along the line C-C in FIG. 24 , as viewed in a direction of the arrows.
In the rotation sensor 1 of the eleventh embodiment, the magnetic detection section 7 has a “D”-like sectional shape and includes a cut portion 7 a . The case 2 includes a cut portion 2 k so as to correspond to the shape of the magnetic detection section 7 .
The remaining configuration is the same as that of the rotation sensor 1 of the ninth embodiment.
According to the rotation sensor 1 of the eleventh embodiment, the magnetic detection section 7 has an asymmetrical shape having directionality. The case 2 also has an asymmetrical shape so as to correspond to the shape of the magnetic detection section 7 . Therefore, when the magnetic detection section 7 is mounted into the case 2 , a direction of assembly is defined.
Further, in an assembly step for the rotation sensor 1 , when the case 2 in which the semi-product is housed is placed inside a die for forming the exterior resin 9 , the direction of assembly of the case 2 can be defined by visual observation. Thus, the workability is improved.
Next, first to fourth steps for manufacturing the rotation sensor 1 of the ninth embodiment, which is illustrated in FIGS. 17 to 19 , are described in order.
The steps until the completion of the magnetic detection section 7 , which is connected to an end of the lead-frame coupled body 3 ZZ made of a metal plate having a rectangular shape, are described in Japanese Patent Application Laid-open No. 2012-2564 referring to FIGS. 4 to 7 , and therefore the description thereof is herein omitted.
First Step
FIG. 27 is a front view illustrating the lead-frame coupled body 3 ZZ and the magnetic detection section 7 in the first step, and FIG. 28 is a sectional view of FIG. 27 as viewed in a direction of the arrow XXVIII.
In this step, the lead frames 3 X, 3 Y, and 3 Z are components of the lead-frame coupled body 3 ZZ in which the lead frames 3 X, 3 Y, and 3 Z are connected by the coupling portions 3 Za (at two positions). The magnetic detection section 7 is connected to the end of the lead-frame coupled body 3 ZZ.
Second Step
FIG. 29 is a front view illustrating the lead-frame coupled body 3 ZZ, the magnetic detection section 7 , and the spacer 13 X in the second step, and FIG. 30 is a sectional view of FIG. 29 as viewed in a direction of the arrow XXX.
The lead-frame interposing portions 3 Xg, 3 Zgx, 3 Yg, and 3 Zgy, which project from the lead-frame coupled body 3 ZZ, are fitted into the two spacer concave-side fitting portions 13 XeL and 13 XeR provided to the spacer 13 X so as to temporarily fix the lead-frame coupled body 3 ZZ.
The two coupling portions 3 Za of the lead-frame coupled body 3 ZZ illustrated in FIG. 31 are cut (cut off).
The cutting may be performed after the spacer 13 Y is assembled to the spacer 13 X.
Next, as illustrated in FIG. 32 that is a sectional view of FIG. 31 as viewed in the direction of the arrow XXXII, the spacer 13 Y is assembled to the lead frames 3 X, 3 Y, and 3 Z.
Next, referring to FIGS. 33 to 36 , a state of assembly of fitting portions of the spacers 13 X and 13 Y and the lead frames 3 X, 3 Y, and 3 Z is sequentially described.
FIG. 33 illustrates fitting portions of the spacer 13 X, the lead-frame coupled body 3 ZZ, and the spacer 13 Y.
FIG. 34 illustrates a state in which the spacer 13 X and the lead-frame coupled body 3 ZZ are fitted to each other so as to complete the temporary assembly.
FIG. 35 illustrates a subsequent state in which the spacer 13 Y is being assembled to the lead-frame coupled body 3 ZZ. FIG. 36 illustrates a state in which the assembly of the spacer 13 X, the lead-frame coupled body 3 ZZ, and the spacer 13 Y is completed.
FIG. 37 is a front view illustrating a state in which the coupling portions 3 Za are removed after the assembly of the spacer 13 X, the lead-frame coupled body 3 ZZ, and the spacer 13 Y is completed. FIG. 38 is a sectional view of FIG. 37 as viewed in a direction of the arrow XXXVIII.
Third Step
Next, as illustrated in FIG. 39 , the internal filling resin 8 that is a mold resin is filled into the internal space of the case 2 .
Next, as illustrated in FIG. 40 and FIG. 41 that is a sectional view of FIG. 40 as viewed in a direction of the arrow XLI, the semi-product is inserted into the case 2 . The positioning portions 3 Xe and 3 Ye are brought into contact with the opening circumferential edge portion 2 d of the case 2 . In a state in which the magnetic detection section 7 is housed in a predetermined position inside the case 2 , the internal filing resin 8 is cured.
For the removal of the coupling portions 3 Za from the lead-frame coupled body 3 ZZ, the coupling portions 3 Za can be removed in the third step. However, the cutting is already completed in the second step as described above. Therefore, the cutting work for the coupling portions 3 Za in a position deeper than the opening 2 c of the case 2 is not required.
Fourth Step
Next, as illustrated in FIG. 42 and FIG. 43 that is a sectional view of FIG. 42 as viewed from a direction of the arrow XLIII, the case 2 including the semi-product housed therein is placed inside a die (not shown) for the exterior resin 9 . Then, by molding, a connector housing for external connection and a sensor exterior part are formed on the case 2 . The opening 2 c side of the case 2 is covered with the exterior resin 9 .
Through the first to fourth steps described above, the rotation sensor 1 of the ninth embodiment is manufactured. | Provided is a rotation sensor capable of reducing manufacturing costs and improving workability. The rotation sensor includes: a case including: a bottom surface portion; and a side surface portion that defines a hollow internal space in cooperation with the bottom surface portion; a plurality of lead frames respectively having distal ends inserted into the case; a magnetic detection section provided to the distal ends of the plurality of lead frames arranged in parallel; a spacer provided between the plurality of lead frames and the side surface portion so as to be held in contact with an internal wall surface of the side surface portion; and an internal filling resin for filling a space portion of the hollow internal space except for the spacer, the magnetic detection section, and the plurality of lead frames. | 6 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is the US National Stage of International Application No. PCT/EP2009/061936, filed Sep. 15, 2009 and claims the benefit thereof. The International Application claims the benefits of European Patent Office application No. 08020190.8 EP filed Nov. 19, 2008. All of the applications are incorporated by reference herein in their entirety.
FIELD OF INVENTION
The invention relates to a gas turbine having a stator blade support, which is essentially hollow-conical or hollow-cylindrical and extends along a machine axis, and having an outer wall, which is essentially hollow-conical or hollow-cylindrical and is segmented into annular segments in the circumferential and/or axial direction, of an annular hot gas path, whose annular segments are attached by means of a number of hook elements to the inside of the stator blade support.
BACKGROUND OF INVENTION
Gas turbines are used in many fields, for driving generators or working machines. In this case, the energy content of a fuel is used to produce a rotary movement of a turbine shaft. The fuel is for this purpose burnt in a combustion chamber, with compressed air being supplied from an air compressor. The working medium which is produced by the combustion of the fuel in the combustion chamber and is at high pressure and high temperature is in this case passed via a turbine unit, which is connected downstream from the combustion chamber and where it is expanded producing work.
In this case, in order to produce the rotary movement of the turbine shaft, a number of rotor blades are arranged on the turbine shaft, are normally combined to form blade groups or blade rows and drive the turbine shaft via the impulse which is transmitted from the working medium. Furthermore, stator blades, which are normally connected to the turbine housing between adjacent stator blade rows and are combined to form stator blade rows, are normally provided to guide the flow of the working medium. These stator blades are attached to a normally hollow-cylindrical or hollow-conical stator blade support.
When designing gas turbines such as these, in addition to the power which can be achieved, particularly high efficiency is normally a design aim. In this case, for thermodynamic reasons, the efficiency can in principle be increased by increasing the outlet temperature at which the working medium flows out of the combustion chamber and into the turbine unit. In this case, temperatures of about 1200° C. to 1500° C. are both desired and achieved for gas turbines such as these.
However, when the working medium is at high temperatures such as these, the components and parts which are subject to these temperatures are subject to high thermal loads. The hot gas channel is normally clad by so-called annular segments, which form axial sections of the outer wall of the hot gas channel. These are normally attached via hook elements to the stator blade support, as a result of which the totality of the annular segments in the circumferential direction, in the same way as the stator blade support, forms a hollow-conical or hollow-cylindrical structure.
The components of the gas turbine can be deformed by different thermal expansion in different operating states, and this has a direct influence on the size of the radial gaps between the rotor blades and the outer wall of the hot gas channel. These radial gaps may be of different size while the turbine is being run up and shut down than during normal operation. When designing the gas turbine, components such as the stator blade support or outer wall must always be designed such that the radial gaps are kept sufficiently large to prevent the gas turbine from being damaged in any operating state. However, a correspondingly comparatively generous design of the radial gaps leads to considerable efficiency losses.
In order to overcome this problem, JP 2005-042612 proposes that the stator blade support being designed such that it can be cooled, with the aim of reducing the thermally dependent deformation. According to JP 54-081409, this problem is intended to be solved by a plurality of gas bleed chambers, which leads to uniform stiffness of the upper and lower housing part.
SUMMARY OF INVENTION
Therefore, the invention is based on the object of specifying a gas turbine which allows particularly high efficiency while maintaining the greatest possible operational safety and life.
According to the invention, this object is achieved in that the hook elements on at least one of the annular segments of the gas turbine as mentioned initially are geometrically matched such that, when not in operation, the outer wall which bounds the hot gas path has an essentially elliptical cross-sectional contour in a section at right angles to the machine axis.
The invention is in this case based on the idea that particularly high efficiency would be made possible by reducing the radial gaps during normal operation, that is to say, for example, during full-load operation of the gas turbine. Until now, it was necessary to design the radial gaps to be comparatively large, because the turbine deforms differently in different operating states. In particular, cylindrically or conically shaped components of the gas turbine become oval, and this must be taken into account when designing the radial gaps. In order to allow the radial gaps to be reduced during the design of the gas turbine, the ovality during operation of the gas turbine should therefore be kept as small as possible. This should be achieved by an appropriately matched cross-sectional contour of the hollow-conical or hollow-cylindrical components of the gas turbine when they are not in operation, that is to say when the gas turbine has cooled down to room temperature. This cross-sectional contour should be designed such that the cross-sectional contour which exists at room temperature after assembly of the gas turbine leads to a cross-sectional contour which is then circular, as a result of the thermal deformations which occur in the operating state. This can be achieved by geometrically matching the hook elements on at least one of the annular segments such that, when not in operation, the outer wall which bounds the hot gas path has an essentially elliptical cross-sectional contour in a section at right angles to the machine axis. The thermal expansion should accordingly not be suppressed, as in the prior art according to JP 2005-042612 and JP 54-081409.
It is relatively simple to appropriately manufacture the annular segments described initially, with which the hot gas path outside the rotor blades is clad. The annular segments form the outer wall of the hot gas path in the axial section of the rotor blades in the circumferential direction and together therefore form the hollow-conical or hollow-cylindrical component of the gas turbine which is closest to the rotor blades. The cross section at right angles to the machine axis through the annular segments which form the outer wall of the hot gas path therefore has the described elliptical cross-sectional contour when not in operation.
The annular segments which form the outer wall of the hot gas path in the axial section of the rotor blades are in this case normally hooked into the stator blade support via hook elements. Since the stator blade support is a relatively massive component which is subject to comparatively severe deformation during operation, the cross-sectional contour which is formed by all the annular segments in the operating state is frequently governed by the attachment or bracing of the annular segments in the stator blade support, and its deformation during operation. It is therefore not absolutely essential for the cold contour of the outer wall, which consists of annular segments, to be manufactured itself in an elliptical shape, since the definition which is forced by the contact points on the hook elements occurs in any case. The compensation for the ovality of the stator blade support can therefore be achieved by advantageously matching only the individual hook elements of the annular segments such that the outer wall has an essentially elliptical cross-sectional contour. Since these annular segments are replaceable maintenance parts, this on the one hand makes it possible to retrofit existing gas turbines while on the other hand making it possible to compensate for manufacturing errors in stator blade supports and, furthermore, allowing particularly simple matching to different methods of operation, including modified other measures to reduce the radial gaps.
In one advantageous refinement, during the production of the hollow-conical or hollow-cylindrical components of the gas turbine, the lengths of the main and secondary axes of the elliptical cross-sectional contour are in each case chosen such that the respective component has an essentially circular cross-sectional contour after the thermal deformation which occurs in the operating state. This can be done, for example, by introduction of ovality offset through 90 degrees with respect to that expected during operation. The elliptical shape of these components is therefore chosen such that the deformations in the operating state are compensated for precisely, such that this results in a circular cross section during operation, and therefore in the same radial gaps over the entire circumference of the gas turbine, that is to say the radial gaps no longer vary over the circumference. Even during the design phase, this therefore allows the radial gaps to be designed to be correspondingly narrow, resulting in higher efficiency of the gas turbine.
Advantageously, the radial lengths of the hook elements are matched, and/or enclosures are arranged in a corresponding holding groove in the stator blade support, in order to vary the radial position of the hook elements. These enclosures are then located between the hooks of the hook elements and the holding groove and therefore lead, seen along the circumference, to different radial positions of the annular segments. Annular segments having radial hooks of different length can therefore de facto either be provided in the stator blade support, distributed along the circumference, or the hook elements of the annular segments are identical along the circumference, in which case enclosures of different thickness are then used for the corresponding hooks, in order to vary the radial position of the annular segments along the circumference.
The explained elliptical configuration of the hollow-conical or hollow-cylindrical components of the gas turbine when not in operation makes it possible to achieve an essentially circular shape for the operating state and, furthermore, the elliptical shape which now exists when not in operation can be taken into account further in the design of the radial gaps and the design of the gas turbine. This problem can be overcome by a gas turbine which is equipped with the described components that have been manufactured with an opposing angle design having a bearing device for the turbine shaft, which is designed such that the turbine shaft can be moved along the turbine axis. This allows the turbine shaft to be moved in the hot gas flow direction in the cold operating state, thus resulting in the radial gaps being enlarged when the outer wall has a hollow-conical shape, with an enlargement of the radius in the direction of the hot gas flow when cold and not in operation, as a result of which the opposing ovality which is still present in the cold state (for example when starting up the gas turbine) does not represent any restriction to the radial gaps which can be achieved in the hot state. This makes it possible to achieve even higher efficiency from the gas turbine.
A gas turbine such as this is advantageously used in a gas and steam turbine installation.
The advantages achieved by the invention are, in particular, that deliberately designing the hollow-conical or hollow-cylindrical components of a gas turbine such that they have an essentially elliptical cross-sectional contour when not in operation, allows the gas turbine to have a particularly high efficiency, by reducing the radial gaps. The previous elliptical deformation, for example of the outer wall of the annular hot gas channel or the inner wall of the stator blade support during operation, is reduced or avoided by elliptical manufacture, in which the ovality which is incorporated in the cold state is rotated through 90° with respect to the ovality which occurs during operation. Unifying the radial gaps on the circumference reduces the flow losses and therefore improves the machine efficiency. In addition, the cold gaps when in the new state can be reduced, since the amount of the ovality need no longer be kept available for gap generation.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be explained in more detail with reference to a drawing, in which:
FIG. 1 shows a half section through a gas turbine,
FIG. 2 shows a cross section through the stator blade support of a gas turbine according to the prior art, and
FIG. 3 shows a cross section through the stator blade support of a gas turbine with an elliptical shape introduced when not in operation.
The same parts are provided with the same reference symbols in all the figures.
DETAILED DESCRIPTION OF INVENTION
The gas turbine 1 as shown in FIG. 1 has a compressor 2 for combustion air, a combustion chamber 4 and a turbine unit 6 for driving the compressor 2 , and for driving a generator, which is not illustrated, or a working machine. For this purpose, the turbine unit 6 and the compressor 2 are arranged on a common turbine shaft 8 , which is also referred to as the turbine rotor, to which the generator and/or the working machine are/is also connected, and which is mounted such that it can rotate about its turbine axis 9 . The combustion chamber 4 , which is in the form of an annular combustion chamber, is fitted with a number of burners 10 for combustion of a liquid or gaseous fuel.
The turbine unit 6 has a number of rotor blades 12 which can rotate and are connected to the turbine shaft 8 . The rotor blades 12 are arranged in the faun of a ring on the turbine shaft 8 and therefore foam a number of rotor blade rows. Furthermore, the turbine unit 6 comprises a number of stationary stator blades 14 , which are likewise attached in the form of a ring to a stator blade support 16 in the turbine unit 6 , forming the stator blade rows. The rotor blades 12 are in this case used to drive the turbine shaft 8 by impulse transmission from the working medium M flowing through the turbine unit 6 . In contrast, the stator blades 14 are used for flow guidance of the working medium M between in each case two successive rows of rotor blades or rings of rotor blades which follow one another, seen in the flow direction of the working medium M. A successive pair from a ring of stator blades 14 or a row of stator blades and from a ring of rotor blades 12 or a row of rotor blades is in this case also referred to as a turbine stage.
Each stator blade 14 has a platform 18 which is arranged as a wall element, in order to fix the respective stator blade 14 to a stator blade support 16 in the turbine unit 6 . In this case, the platform 18 is a thermally comparatively severely loaded component, which forms the outer boundary of a hot gas channel for the working medium M flowing through the turbine unit 6 . Each rotor blade 12 is analogously attached to the turbine shaft 8 via a platform 19 , which is also referred to as a blade foot.
Annular segments 21 are in each case arranged on a stator blade support 16 in the turbine unit 6 , between the platforms 18 , which are arranged separated from one another, of the stator blades 14 in two adjacent stator blade rows. The inner surface of each annular segment 21 is in this case likewise subject to the hot working medium M flowing through the turbine unit 6 , and accordingly bounds the annular hot gas path on the outside, as its outer wall. In the radial direction, the outer wall is separated by a radial gap from the outer end of the rotor blades 12 opposite it. The annular segments 21 which are arranged between adjacent stator blade rows are in this case used in particular as shroud elements, which protect the stator blade support 16 or other housing built-in parts against thermal overloading from the hot working medium M flowing through the turbine 6 .
In the exemplary embodiment, the combustion chamber 4 is in the form of a so-called annular combustion chamber, in which a multiplicity of burners 10 , which are arranged around the turbine shaft 8 in the circumferential direction, open into a common combustion chamber area. For this purpose, the combustion chamber 4 is in its totality in the form of an annular structure, which is positioned around the turbine shaft 8 .
FIGS. 2 and 3 now schematically show the stator blade support 16 for the gas turbine 1 in the form of a cross section at right angles to the turbine axis 9 , on the one hand on the left when not in operation, that is to say when the gas turbine 1 is cold, and on the right in the operating state, that is to say at the operating temperature. When not in operation, the stator blade support 16 is accordingly at a material temperature which corresponds to the ambient temperature of the gas turbine. The operating temperature, in contrast, is considerably higher; beyond 100° C. The stator blade support 16 is in this case composed of an upper segment 24 and a lower segment 26 . The two segments 24 , 26 are connected to one another via flanges 28 , and each form a connecting joint 30 at their connecting point.
During operation, as is illustrated on the right in FIG. 2 , the high operating temperatures in the gas turbine 1 result in deformation of the stator blade support 16 according to the prior art, such that the distance between the peaks 32 of the respective upper and lower parts 24 , 26 is increased. The cross section of the stator blade support 16 is in this case deformed to form a vertical ellipse. A circular contour is illustrated, in the form of dashed lines, for comparison.
This deformation can now be compensated for by deliberately introducing an elliptical configuration for the cross section of the stator blade support 16 when cold and not in operation, as is illustrated in FIG. 3 . When not in operation, the distance between the peaks 32 of the upper and lower segments 24 , 26 is shortened, that is to say the cross section when not in operation is in the form of a horizontal ellipse, as is illustrated on the left in FIG. 3 . The thermally dependent expansion and enlargement of the distance between the peaks 32 in operation, as is illustrated on the right, then results in the stator blade support 16 having an essentially circular shape, as is shown on the right in FIG. 3 .
In order to avoid any restrictions resulting from the ovality introduced in terms of the radial gap when not in operation, the turbine shaft 8 can be moved along the turbine axis 9 . In the cold state, that is to say when the hot gas channel has an elliptical shape, the turbine shaft 8 can then be moved in the direction of the hot gas flow direction. The conical shape of the hot gas channel results in the radial gap being enlarged. When a circular cross section then occurs as a result of thermal deformation in the operating state, the turbine shaft 8 is moved in the opposite direction, in order to optimize the radial gap.
Alternatively, the annular segments 21 can also be configured by correspondingly introduced ovality such that the hot gas channel has a circular cross section during operation. For this purpose, the hook elements for attachment of the annular segments 21 to the stator blade support 16 may have different lengths, that is to say they may have different lengths with different circumferential positions, or enclosures can be introduced between the hooks and holding groove on the stator blade support 16 , which influence the radial position of the relevant annular segments 21 by means of hook elements of the same length. This is because the cross-sectional contour at right angles to the machine axis through the radially outer wall, which is formed from the annular segments 21 , of the annular hot gas channel is largely determined by the deformation of the stator blade support 16 , which is passed on through the hook elements of the annular segments. Accordingly, instead of the stator blade support 16 , as shown in FIG. 2 and FIG. 3 , this can also mean an outer wall—which then has no flange—of the hot gas path through a gas turbine.
The ovality in the operating state can be avoided by such elliptical shaping of the stator blade support 16 or of the outer wall, which consists of annular segments, of the hot gas channel of the gas turbine 1 . When designing the gas turbine 1 , this makes it possible to make the radial gaps correspondingly smaller, which overall results in the gas turbine 1 having a considerably higher efficiency without any operational reliability losses. | A gas turbine including a plurality of hook elements disposed one inside the other and designed substantially in the form of hollow cones or hollow cylinders, and including a stator blade support, is intended to enable an especially high efficiency while maintaining the greatest possible operating safety and operating life. To this end, at least one of the hook elements or the stator blade support has a substantially elliptical cross-sectional contour. | 5 |
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation of U.S. application Ser. No. 12/166,420, filed Jul. 2, 2008 now U.S. Pat. No. 7,891,834, which was a continuation of U.S. application Ser. No. 10/518,219, filed Dec. 16, 2004,now U.S. Pat. No. 7,461,944, which was the National Stage Entry of International Application No. PCT/US03/19385, filed Jun. 20, 2003 which claimed the benefit of US Provisional Application No. 60/390,245, filed Jun. 20, 2002, the entire disclosures of which are hereby incorporated herein by reference.
BACKGROUND OF THE INVENTION
The present invention generally relates to portable lighting devices (e.g., flashlights) and, more particularly, to a lighting device using multiple light emitting diodes (LEDs) as the light source.
Many light illuminating devices, such as flashlights, typically employ an incandescent lamp as the light source. Light emitting diodes (LEDs) offer many advantages over conventional incandescent lamps. LEDs are durable, have a lamp life of about 8,000 hours; and because they operate at low current drains, the useful life of energy storage batteries powering LEDs is extended. Despite these advantages, there are certain aspects of LEDs which limit their usefulness in certain applications, such as in portable lighting devices. The best standard 5 mm white LEDs currently available on the market are typically rated at about 3.6 volts, 30 milliamps (mA), and produce less than four (4) lumens of light. In comparison, an incandescent lamp used in conventional lighting devices with a similar voltage rating will typically produce light output that can range from less than ten (10) lumens to greater than forty (40) lumens or anywhere in between.
A solution to overcome the limitation of the LED currently being investigated is to use multiple LEDs as the light source in the lighting device. Some portable lighting devices currently use up to ten (10), or even more, LEDs as the light source, which increases the cost of the lighting device. Additionally, the light rays emitted by each LED are dispersed (e.g., forty degrees), and simply using multiple LEDs as the light source does not cure this problem.
One further approach to the solution is disclosed in U.S. Pat. No. 5,174,649 which employs one or more LEDs that illuminate portions of a single refractive lens element having hyperboloidal surfaces which translate the LEDs emitted rays into substantially parallel beams within the single refractive lens element. Another approach employing multiple LEDs in a flashlight is disclosed in U.S. Pat. No. 6,485,160 which employs multiple reflector wells, each housing an LED and a lens. While such approaches provide some directivity and concentration of light rays emitted from multiple LEDs, drawbacks still exist. For example, the formation of a complex refractive lens element and the requirement of the multiple reflector wells add to the cost and complexity of the lighting device.
In view of these disadvantages, it would be desirable to have an LED-based lighting system for a portable lighting device, which emitted light in a directed and concentrated manner.
SUMMARY OF THE INVENTION
In one aspect, a lighting device includes a housing, multiple light emitting diodes (LEDS), and multiple magnifier lenses. The multiple LEDS and the multiple magnifier lenses are located in the housing. Each of the magnifier lenses corresponds to a different one of the LEDS, and there are less magnifier lenses than LEDS. Each LED that has a corresponding magnifier lens is arranged with respect to its magnifier lens so that substantially all of the light emitted by the LED only traverses its corresponding magnifier lens. At least one of the LEDS emits light that does not traverse any of the multiple magnifier lenses.
In another aspect, a lighting device includes a housing, first and second light emitting diodes located in the housing, a first magnifier lens arranged in a light path of the first light emitting diode that focuses a first light beam of the first light emitting diode onto a target area, wherein substantially all of the first light beam traverses the first magnifier lens, a second magnifier lens arranged in a light path of the second light emitting diode that focuses a second light beam of the second light emitting diode onto the target area, wherein substantially all of the second light beam traverses the second magnifier lens, wherein substantially all of the first and second light beams only illuminate the target area, a third light emitting diode located in the housing, wherein the third light emitting diode generates a third light beam that does not traverse the first and second magnifier lenses, a support member that respectively supports the first and second magnifier lenses relative to the first and second light emitting diodes, and a rear housing coupled to a back side of the housing, the rear housing having a battery compartment.
In another aspect, a method includes focusing a first light beam generated by a first light emitting diode with a first lens at a target region, focusing a second light beam generated by a second light emitting diode with a second lens at the target region, wherein substantially all of the first and second light beams illuminate only the area within the target region, and emitting a third light beam that does not traverse the first and second lenses.
In accordance with the teachings of the present invention, a lighting device is provided which uses multiple LEDs to illuminate a target area. The lighting device includes a housing and first and second light emitting diodes located on the housing and spaced from each other. The lighting device also includes a first magnifier lens arranged in a light path of the first light emitting diode for focusing a first light beam onto a target area, and a second magnifier lens arranged in a light path of the second light emitting diode for focusing a second light beam onto the target area. The lighting device further has a support member for supporting the first and second magnifier lenses relative to the first and second light emitting diodes, respectively.
In another aspect of the present invention, the support member is a cover extending over the front of the housing, and the cover has a non-reflective inner wall. In a further aspect of the present invention, the lighting device comprises first and second convex magnifier lenses. The axes of the first and second LEDs are parallel to each other, and each magnifier lens is positioned orthogonal to the axis of the first and second LEDs, respectively.
The lighting device of this invention takes advantage of the positive attributes of LEDs, while minimizing costs. The lighting device is designed to produce a spotlight beam from each individual LED and magnifier lens combination which overlaps with the spotlight beam produced by each adjacent LED and magnifier lens combination. The target area is illuminated with a substantially single spotlight beam which shows excellent symmetry and high, uniform intensity.
These and other features, advantages and objects of the present invention will be further understood and appreciated by those skilled in the art by reference to the following specification, claims and appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will now be described, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a perspective view of a headlamp lighting device utilizing the multiple LED lighting system of the present invention;
FIG. 2 is an exploded view of the lighting device of FIG. 1 ;
FIG. 3 is a cross-sectional view of the front portion of the lighting device;
FIG. 4 is a top view layout of the multiple LEDs and magnifier lenses in the lighting device of the present invention; and
FIG. 5 is a reduced top view layout of the multiple LEDs and magnifier lenses, further illustrating the resultant spotlight beam coverage.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1 , a lighting device 10 is shown employing multiple light emitting diodes (LEDs) and multiple magnifier lenses according to one embodiment of the present invention. The lighting device 10 is shown as a headlamp flashlight (e.g., spotlight) having an adjustable strap 16 adaptive to be worn on the head of a user. While the lighting device 10 is shown and described herein as a headlamp flashlight, it should be appreciated that the lighting device 10 may be employed in any of a number of lighting systems to provide light illumination to a target area.
As shown in FIGS. 1-3 , the lighting device 10 generally includes a rear housing 14 connected to an adjustable strap (headband) 16 . The rear housing 14 provides a compartment for housing a plurality of energy storage batteries 52 (e.g., AA-type alkaline batteries) which serve as the electrical power source. The lighting device 10 further includes a front housing assembly 12 containing the light source and light focusing components of the lighting device 10 . The front housing assembly 12 has a molded housing 18 forming the rear and side walls. Located within the housing 18 is a printed circuit board 20 having a light control switch 22 and other electrical circuitry (not shown) for controlling energization of the lighting device 10 by controlling the application of electrical current from the power source to the light source. According to one embodiment, the control switch 22 is a manually-actuated, three-position switch having a first position in which all the LEDs are turned off, a second position to turn on two LEDs, and a third position to turn on a third LED.
The lighting device 10 includes, as the light source, a plurality of light emitting diodes (LEDs) that are shown connected to the printed circuit board 20 which, in turn, is connected to housing 18 . The LEDs include a first LED 24 spaced from a second LED 26 for generating first and second light beams, respectively. Also shown disposed between first and second LEDs 24 and 26 is a third LED 28 for emitting a third light beam. The LEDs 24 , 26 , and 28 used as the light source in the lighting device 10 of the present invention are commercially available from a variety of sources. One example of a commercially available white LED is Model No. NSPW500BS available from Nichia Corporation. It should be appreciated that various kinds of LEDs are readily available from several commercial suppliers. The LEDs 24 , 26 , and 28 can be of any color, depending upon the choice of the users. According to one embodiment, the first and second LEDs. 24 and 26 are white LEDs made by Nichia Corporation, and the third LED 28 is a red-colored LED.
The lighting device 10 also includes an inner cover 30 fastened to front housing 18 to provide a covering over the printed circuit board 20 . Inner cover 30 has openings for allowing the first, second, and third LEDs 24 - 28 to extend therethrough forward of the inner cover 30 . Assembled to the front of inner cover 30 is an outer cover and support member 32 that covers the front face of cover 30 forward of LEDs 24 , 26 , and 28 . Outer cover and support member 32 supports the first and second magnifier lenses 34 and 36 and forms a cover on front housing 18 . The inner wall of outer cover and support member 32 is non-reflective, and thus does not reflect any substantial light rays. The first and second magnifier lenses 34 and 36 may be integrally formed within the outer cover and support member 32 or may otherwise be attached to outer cover and support member 32 . According to one embodiment, the outer cover and support member 32 is made of a polymeric material (e.g., plastic) and the magnifier lenses 34 and 36 are integrally formed within the polymeric material. In a further embodiment, cover member 32 is made of a substantially transparent material that allows light rays to pass through.
The magnifier lenses 34 and 36 are light transparent optics magnifiers that magnify light transmitted through the lens and direct the magnified light in a light beam. The magnifier lenses 34 and 36 may each be configured as a double convex magnifier lens as shown, according to one embodiment. According to another embodiment, the magnifier lenses 34 and 36 may each include a plano convex magnifier lens. The magnifier lenses 34 and 36 each have at least one convex surface to provide magnification to focus the light beam. The magnifier lenses 34 and 36 can be made of any transparent material, such as glass or polymer (e.g., polycarbonate). The dimensions of the magnifier lenses 34 and 36 can vary depending upon the spotlight diameter desired by the user. The magnifier lenses 34 and 36 used in the present invention are commercially available from a variety of sources and may each include a polycarbonate double convex magnifier lens having Model No. NT32-018, commercially available from Edmund Industrial Optics, having a diameter of nine millimeters (9 mm) and a focal length of nine millimeters (9 mm).
Electrical power lines 54 and 56 extend between the printed circuit board 20 within the front housing 18 and the energy storage batteries 52 located in rear housing 14 . The electrical power lines 54 and 56 supply electrical current (e.g., direct current) from the batteries 52 to the LEDs 24 - 28 to power the LEDs 24 , 26 , and 28 which generate the corresponding light beams. According to one embodiment, the third LED 28 may be illuminated separate from LEDs 24 and 26 to provide a light beam of a different color as compared to LEDs 24 and 26 . According to one embodiment, LEDs 24 and 26 provide a white light beam, while LED 28 provides a red colored light beam.
Formed at the bottom of front housing assembly 12 , along the bottom edge of support member 32 , is a hinge assembly 58 that is connected to the rear housing 14 . Hinge assembly 58 is rotatable about a horizontal axis to allow the front housing assembly 12 and corresponding LED 24 - 28 and magnifier lenses 34 and 36 to rotate relative to the rear housing 14 . This enables a user to rotate front housing assembly 12 to adjust the height positioning of the illuminating light beams.
The lighting systems arrangement of the LEDs 24 - 28 and magnifier lenses 34 and 36 is best illustrated in FIGS. 3 through 5 . First and second LEDs 24 and 26 are arranged relative to magnifier lenses 34 and 36 to produce first and second light beams 44 and 46 , respectively. The first LED 24 illuminates the first magnifier lens 34 to generate a first light beam generally within a defined full angle field of view of about forty degrees(40°). Substantially all of the light generated by the first LED 24 is illuminated onto the first magnifier lens 34 which magnifies and redirects the first light beam in a path shown in FIGS. 4 and 5 by dashed lines 44 . The second LED 26 likewise illuminates the second magnifier lens 36 to generate a second light beam within a defined full angle field of view of about forty degrees(40°). The light beam generated by the second LED 26 is illuminated onto the second magnifier lens 36 which refocuses and directs the light beam in a second path shown by dashed lines 46 .
Light beams 44 and 46 are shown substantially overlapping and substantially cover a common target area 50 to form a single spotlight having excellent symmetry and uniform intensity. By employing the arrangement of the first and second LEDs 24 and 26 and magnifier lenses 34 and 36 , respectively, focused onto a single target area 50 , increased brightness illumination is achieved in target area 50 .
The third LED 28 is shown generating a light beam in a path shown by phantom lines 48 that extends substantially between an opening between magnifier lenses 34 and 36 . The light beam 48 generated by LED 28 is emitted within a full angle wide field of view of about forty degrees(40°). Accordingly, a substantial portion of the light beam 48 generated by a third LED 28 is not directed through a magnifier lens and, hence, is not magnified and focused onto the focal target area 50 . Instead, the third LED 28 illuminates a wider angle of coverage and, thus, operates more as a floodlight.
Each of the three LEDs 24 - 28 includes an electrically powered diode shown as diodes 24 A, 26 A, and 28 A, respectively. The diodes 24 A, 26 A, and 28 A generate light rays in response to the application of electrical current. Each of the diodes 24 A, 26 A, and 28 A are shown enclosed within a transparent housing 24 B, 26 B, and 28 B, respectively. While lamp-type LEDs are shown and described herein, it should be appreciated that other LEDs may be employed in the lighting device 10 .
The first and second LEDs 24 and 26 are spaced apart from each other by distance D which is measured from the center of the LEDs. In one embodiment, distance D is about 18.2 mm. The magnifier lenses 34 and 36 can be glass (SF5) double convex magnifier lenses which, in one embodiment, are 9 mm in diameter with a 9 mm effective focal length. Magnifier lens 34 is positioned orthogonal to first LED 24 , while magnifier lens 36 is positioned orthogonal to second LED 26 . The central focal axes of first and second LEDs 24 and 26 are parallel to each other. The surface of the magnifier lenses 34 and 36 can be placed from the tip of their respective LEDs at a distance L A and L B to allow for a back focal length of 7.9 mm, according to one embodiment. This is the distance L A and L B between the focal point within the first and second LEDs 24 and 26 and the surface of the corresponding lenses 34 and 36 , respectively.
The spotlight beam produced from the first LED 24 and magnifier lens 34 combination substantially overlaps with the spotlight beam produced from the second LED 26 and magnifier 36 combination. The overlap may be less than a complete overlap of light beams 44 and 46 due to the offset arrangement of the perpendicular LED 24 and 26 and magnifier lenses 34 and 36 combinations. However, the combination of LEDs 24 and 26 and magnifier lenses 34 and 36 can result up to a two hundred percent (200%) increase in beam intensity, as compared to a single LED alone.
Accordingly, the lighting device 10 of the present invention advantageously produces an enhanced intensity and uniform spot beam focused onto a target area 50 by employing multiple LEDs at a minimal cost. While light beams 44 and 46 do not completely overlap when offset magnifier lenses 34 and 36 are arranged orthogonal to LEDs 24 and 26 , the resultant light beams 44 and 46 do substantially overlap in target area 50 . The overlapping target area 50 could further be refined by tilting magnifier lenses 34 and 36 towards a common target area so as to focus beans 44 and 46 onto an overlapping target area. However, the tilting of magnifier lenses 34 and 36 may change the shape of the resultant light beams 44 anal 46 .
The power source used in the light system of the present invention can be any conventional power source. AC and DC current can be used. Conventional dry cell batteries, for example, zinc/MnO 2 , carbon/zinc, nickel metal hydride, or lithium-based electrochemical cells can all be used.
It will be understood by those who practice the invention and those skilled in the art, that various modifications and improvements may be made to the invention without departing from the spirit of the disclosed concept. The scope of protection afforded is to be determined by the claims and by the breadth of interpretation allowed by law. | A lighting device includes a housing, multiple light emitting diodes (LEDS), and multiple magnifier lenses. The multiple LEDS and the multiple magnifier lenses are located in the housing. Each of the magnifier lenses corresponds to a different one of the LEDS, and there are less magnifier lenses than LEDS. Each LED that has a corresponding magnifier lens is arranged with respect to its magnifier lens so that substantially all of the light emitted by the LED only traverses its corresponding magnifier lens. At least one of the LEDS emits light that does not traverse any of the multiple magnifier lenses. | 5 |
DESCRIPTION OF THE INVENTION
The present invention relates to a surgical device that is used to repair an aneurysm.
BACKGROUND OF THE INVENTION
An aneurysm is a localized dilation of a blood vessel, usually an artery, due to a weakening of the vessel wall. The dialyzed portion of the vessel wall expands and contracts with the rise and fall of the blood pressure within the vessel. If left untreated, the aneurysm will continue to expand and will eventually rupture, usually resulting in a fatal hemorrhage.
Aneurysms are usually treated by relatively high risk surgery involving prosthetic graft replacement of the diseased artery. Aneurysms can also be treated by placing a flexible woven tube within the aneurysm. Alternatively, they are treated with drugs.
OBJECTS OF THE INVENTION
It is an object of the invention to stop systolic pulsing in an aneurysm and to lower blood pressure in the aneurysm during the diastolic phase of the heat beat.
A further object of the invention is to insert a spring loaded one-way valve against the inner wall of an artery at the site of leakage of arterial blood into an aneurysm.
SUMMARY OF THE INVENTION
The present invention is an improved surgical device which relieves systolic pressure within an aneurysm. It is comprised of catheter tubing having a distal end with pie-shaped flaps, and a stent in the form of a helical coil spring. The spring is compressed to a smaller diameter by winding the coil of the spring tighter, and is inserted into the catheter tubing. One end of the spring is positioned in the distal end of the catheter tubing and the other end of the spring is engaged by a ram within the catheter tubing. The spring is open at both ends and has a one-way valve in the form of a helical flap between the coils of the spring.
The catheter tubing is inserted into the artery on one side of the aneurysm and is pushed through the artery to position the spring within the catheter to bridge the site of blood leakage into the aneurysm. After insertion, the catheter tubing is pulled back while using the ram to hold the spring in place within the artery at the aneurysm. As the spring emerges from the catheter, it expands and causes the pie-shaped flaps to open and expand against the interior of the blood vessel wall. As the spring expands, it unwinds and slides along the ramps formed by the expanded pie-shaped flaps of the receding catheter. When the pressure rises in the artery, the helical flap on the spring within the aneurysm prevents the flow of blood into the swollen part of the aneurysm and prevents the application of systolic pressure to the swollen part of the aneurysm. When the pressure in the vessel falls, high blood pressure in the swollen part of the aneurysm is relieved through the helical flap.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an axial sectional view of the surgical device of the present invention.
FIG. 2 is an end view of the surgical device of FIG. 1 showing the flaps at the distal end of the surgical device,
FIG. 3 is an enlarged axial sectional view of a portion of the stent of the invention showing the details of the coil and flap structure of the stent.
FIG. 4 is an enlarged axial sectional view of the stent of the invention in place within an aneurysm with the catheter tubing completely removed.
FIG. 5 illustrates a fragmentary view of a linear stock of material which can be formed into the stent of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
As shown in FIG. 1, a stent in the form of a spring 24 is enclosed within a catheter 11. The spring is preferably made out of super elastic material, such as nickel-titanium alloy sold under the names Tinel or Nitinol. The spring is coaxially wound under stress so as to be of a smaller diameter and so that the spring will expand radially when released from the catheter 11. Within the catheter, the coils of the spring 24 have little or no space between them. A helical flap 21 extends between the coils of the spring on the radially inward side of the coils. As best shown in the enlarged view of FIG. 3, the flap 21 may be made out of a flexible elastomeric material and has one side permanently cemented to the spring coil and has the other side biased in engagement with the adjacent loop of the coil so as to form a valve which permits flow through the flap from outside of the spring coils to the inside of the spring coil, but not vice versa. Alternatively, the spring and flap may be a one-piece structure formed from linear stock of the superelastic material. FIG. 5 illustrates a fragmentary view of the linear stock in which a cylindrical rod 31 is formed of one piece with flap 33. When the linear stock is worked into a helical spring shape, the flap 33 will form a one-way valve on the coils of the spring.
A ram 13 as shown in FIG. 1 abuts the proximal end of the spring, but is not attached to the spring. The ram 13 is supported on the end of a stiff flexible wire 14 extending back through the catheter.
To effect the repair of an aneurysm, the catheter tubing 11 is inserted into the artery and pushed past the site of the aneurysm to be repaired so that the spring bridges the site of blood leakage into the aneurysm. The helical flap should project in the opposite direction from blood flow within the artery. Accordingly, if the catheter is inserted through the aneurysm from the downstream side, the flap should extend toward the distal end of the catheter as shown in FIG. 1. The catheter tubing is then pulled back while using the ram to hold the spring 24 in place. As the catheter tubing is pulled back, the wire 14 used to maintain the position of the ram 13, which holds the spring in place in the artery. As shown in FIGS. 1 and 2, the distal end of the catheter is formed into a cone shape comprising flexible pie shaped flaps 26, which are pushed outwardly by the spring as the spring emerges from the catheter. The pie-shaped flaps have a dimension in the axial direction of the catheter so that when they are pushed outwardly, they will engage the inner surface of the blood vessel wall. As the spring 24 expands and unwinds upon emerging from the catheter 11, the coils of the spring separate and slide down the ramp formed by the pie-shaped flaps. The slope of the ramp formed by the open flaps is gradual enough so that the unattached end of the helical flap 21 remains in engagement with the adjacent spring coil loop and the helical flap orientation providing the one-way valve function is not interferred with. When the entire spring has emerged from the catheter, the catheter and the ram are withdrawn from the artery as a unit leaving the spring in place. To insure that the spring has been completely pushed out of the catheter, part of the ram has to project from the catheter. The axial dimension of the ram is made long enough to avoid any danger of the ram coming all the way out of the catheter as the spring is pushed out.
The spring 24 expands against the blood vessel wall upon emerging from the catheter, and the flap 21 forms a one-way flow barrier at the site of blood leakage into the aneurysm. When the pressure in the artery rises to the systolic pressure, the flap 21 is held closed by the pressure in the artery and blood does not flow from the vessel into the swollen part of the aneurysm. When the blood pressure in the vessel decreases to the diastolic pressure, higher pressure in the aneurysm will be relieved by the flow of blood out of the swollen portion of the aneurysm through the helical flap. In this manner, the spring with the helical flap relieves systolic pressure from the swollen part of the aneurysm preventing further enlargement of the aneurysm and greatly reducing the danger of aneurysm rupture.
While the invention has been described in terms of the aforementioned embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the appended claims. | A surgical device is provided to reduce the size of and relieve the pressure within an aneurysm. The surgical device is comprised of catheter tubing containing a spring wound under stress. The catheter is inserted through the aneurysm to be repaired and the catheter is then pulled back leaving the spring to expand within the aneurysm. The spring has a one-way helical flap mounted between the spring coils. The flap allows the blood to flow from the swollen part of the aneurysm but not to enter it. | 0 |
This application claims priority under 37 CFR §119(e) to Provisional Application Ser. No. 60/029,761 filed Oct. 24, 1996, which is incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
The present invention relates to the use of three different genes, p53, Pax5, and HSV-tk, to kill cancer cells in a variety of human malignancies.
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BACKGROUND OF THE INVENTION
Although the important role of p53 and mutations in the p53 gene in cancer etiology has been established and gene transfer has advanced enormously in the last ten years only a limited number of studies have addressed the transfer of the p53 gene into malignant cultured cells to render them non-tumorigenic after injection into nude mice; even a smaller number of studies have used transfer of the p53 gene in animal models (for example Ko, et al., 1996). A clinical protocol at M. D. Anderson Cancer Center (Houston, Tex.) proposed the transfer of wt p53 gene with and without cisplatin in non-small cell lung cancer patients shown to have mutations in the p53 gene using adenovirus5-CMV-p53 construct (Roth, 1996) and p53 adenovirus driven by the b-actin promoter (Roth, et al., 1996).
Cells from over 85% of human malignancies are associated with mutations in the p53 tumor suppressor gene. The wild-type (normal, non mutated) p53 gene plays a pivotal role in arresting the cell cycle and the proliferation of cells after severe damage to the DNA; the mechanism is thought to involve the upregulation of the p21/WAF-1/Cip-1 gene (see below) whose product can interact with PCNA (proliferating cell nuclear antigen), an accessory molecule to DNA polymerase d causing inhibition in DNA replication but also by inhibition of CDK (cyclin-dependent kinase) by p21; CDK is responsible for phosphorylating RB at a strategic site causing transversion of the cell cycle through the G1/S checkpoint (Boulikas, 1997).
Furthermore, p53 upregulates the death-inducing gene BAX and down-regulates the Bcl-2 gene promoting cells to enter the apoptotic pathway; mutant p53, such as that found in the majority of human tumors, has lost the capacity of transactivating the p21, BAX and other genes; indeed, the most frequent inactivating mutations occur at the DNA-binding domain of p53 at strategic amino acid sites that contact DNA.
Although the cause versus effect of p53 mutations on human malignancies is not clear for many cases, overexpression of an exogenous wild-type (wt) p53 gene followed by suppression of the endogenous mutated gene of p53 that can have an antagonizing effect to wt p53, is an approach found to suppress tumorigenicity of cells in culture and is proposed here as a method for cancer treatment.
Central to this patent is our demonstrated ability to specifically target tumor cells in culture using the luciferase reporter gene, as well therapeutically important genes, in supercoiled plasmids under control of tissue-specific and tumor specific control elements including but not limited to matrix-attached regions (MARs) (Boulikas, et al., in preparation).
MARs are claimed as largely responsible for mediating the effects of p53 on cell cycle arrest both in the sense that the regulatory regions of p53 targets (p21, BAX, PCNA regulatory regions) might be associated with the nuclear matrix as well as by the established property of MARs to be enriched in triplex-, cruciform- and other unusual DNA structures including stretches of cruciforms with insertion deletion mismatches. We claim that wt and mutant (mu) p53 interact differently with MAR DNA.
I. p53 as a Tumor Suppressor Protein
Alterations in the p53 tumor suppressor gene appear to be involved, directly or indirectly, in the majority of human malignancies (Vogelstein, 1990). Both alleles of p53 need to be mutated or altered for transformation. Introduction of a null mutation by homologous recombination in murine embryonic stem cells gave mice which appeared normal but were susceptible to a variety of neoplasms by 6 months of age (Donehower, et al., 1992; Harvey, et al., 1993).
The tumor suppressive activity of p53 seems to involve at least four independent pathways: (i) upregulation of specific genes most important of which appears to be p21; p21 up-regulation inhibits the activity of cyclin-dependent kinases (CDKs) leading to inability to phosphorylate RB and to release E2F from its complex with RB; released E2F upregulates genes whose products are needed for DNA synthesis (reviewed by Boulikas, 1995e). p21 induction also leads to p21 association with proliferating cell nuclear antigen (PCNA) leading to the inactivation of the PCNA function as an auxiliary factor for DNA polymerase d and to arrest in DNA synthesis in S phase; (ii) induction of the death-promoting bax gene and down-regulation of bcl-2 gene as a mechanism which eliminates oncogenic virus-infected and transformed cells and as an important mediator of apoptosis during embryogenesis and in B cell maturation; (iii) direct interaction of p53 with origins or replication preventing firing and initiation of DNA replication; (iv) induction of Gadd45 leading to growth arrest; (v) a role of p53 in DNA repair; p53 is believed to patrol the genome for small insertion deletion mismatches (Lee, et al., 1995) or free ends of DNA able to attract RPA, an accessory to DNA polymerases a and d as well as TFIIH at the damaged sites (both TFIIH and RPA have a demonstrated role in DNA repair) and to induce arrest in the cell cycle or apoptosis after DNA damage (see below); (vi) upregulation of the gene of thrombospondin inhibiting which inhibits neovascularization in solid tumors (Dameron, et al., 1994); and (vii) an immune response in solid tumors after local injection of the adenoviral/p53 gene which elicits an immune reaction leading to tumor necrosis (Ko, et al., 1996).
Protein p53 appears to be a transcription factor able to recognize specific regulatory regions in a number of genes via its central DNA-binding domain; the DNA sequence-specific binding of wt p53 is regulated by the C-terminal domain of p53 and is activated by a variety of posttranslational modifications (Hupp, et al., 1992; reviewed by Hupp and Lane, 1994).
Increased levels of p53 up regulate the expression of specific genes including Cip-1/Waf-1/p21 (El-Deiry, et al., 1993), GADD45 (Kastan, et al., 1992), cyclin G (Okamoto and Beach, 1994), and mdm2 (Perry, et al., 1993; Barak, et al., 1993; Momand, et al., 1992) which is induced by UV damage in a p53-dependent pathway (Perry, et al., 1993). Other genes up-regulated by p53 include human PCNA (Shivakumar, et al., 1995), mouse muscle creatine kinase MCK (Zambetti, et al., 1992), EGFR (Deb, et al., 1994), GADD45 (Kastan, et al., 1992), the potent promoter of the death pathway Bax (Miyashita and Reed, 1995), and thrombospondin-1 (Dameron, et al., 1994).
Mdm2 acts as a feedback loop for the biological functions of p53 apparently to moderate the G1/S arrest or apoptosis triggered by p53 following severe damage to DNA. Mdm2 protein associates with p53 causing p53 inactivation by preventing its sequence-specific binding to regulatory targets in DNA (Momand, et al., 1992; Oliner, et al., 1992). Elevated levels of Mdm2 mimic the effect of T antigen, E1l B of adenovirus, E6 of HPV, which also inactivate p53 in a similar manner; overexpression of Mdm2 can block the induction of apoptosis by p53 (Chen, et al., 1994).
Gadd45 is believed to inhibit cell cycle progression; however, the mechanism has not been elucidated (Papathanasiou, et al., 1991).
The PCNA promoter is up-regulated in the presence of moderate amounts of wt p53; however, at higher levels of wt p53 the PCNA promoter is inhibited whereas tumor-derived p53 mutants activate the PCNA promoter (Shivakumar, et al., 1995); it has been suggested that the moderate elevation in wt p53 seen after DNA damage induces PCNA to cope with its DNA repair activities (Shivakumar, et al., 1995); this inhibition in DNA replication but stimulation in repair by p53 might be accomplished by an independent pathway involving induction of p21 (El-Deiry, et al., 1993) which interacts with PCNA protein auxiliary to DNA polymerase d to inhibit the replication but not the repair functions of PCNA (Li, et al., 1994).
The bax gene which induces apoptosis is upregulated by p53 whereas the bcl-2 gene which inhibits apoptosis in B cells is down-regulated by p53 (Miyashita, et al., 1994a, 1994b; Miyashita and Reed, 1995). Initiated cancer cells may lead to tumor development only when a dysfunction in their apoptotic pathway takes place; some of the mechanisms leading to inactivation of the apoptotic pathway in cancer cells may result from an up-regulation in the bcl-2 gene (a Bcl-2 chimeric factor is produced in leukemias as a result of a translocation) or down-regulation of the bax gene. Gene therapy for cancer could involve restoration of the apoptotic pathway in cancer cells leading to their suicidal death; this could be effected by overexpression of the bax gene or in the suppression of the endogenous bcl-2 gene for example using p53 expression vectors).
p53 binding sites have been found at the origin of replication of polyomavirus with an inhibitory effect on virus replication in vitro (Miller, et al., 1995) and at the SV40 ORI (Bargonetti, et al., 1991) as well as in putative cellular origins of replication (Kern, et al., 1991). p53 interacts with replication protein A (RPA) (implicated in DNA replication and in repair; interaction of p53 inhibits the replication functions of RPA (Dutta, et al., 1993) although interaction of p53 with RPA via its acidic domains stimulate BPV-1 DNA replication in vitro (Li and Botchan, 1993). Immunolocalization of p53 (also of RB and host replication proteins) at foci of viral replication in HSV-infected cells (Wilcock and Lane, 1991) provided further evidence for a direct interaction of p53 with proteins (or DNA sequences) at the replication fork. Wild-type p53 suppressed DNA replication in vitro when the p53 binding site (RGC) 16 from the ribosomal gene cluster was cloned on the late side of the polyomavirus (Py) core origin; when mutated p53-binding sites were used, the inhibition in Py replication was not observed. In addition, RPA (able to interact directly with p53) was unable to relieve the p53-mediated repression in Py replication.
The tumor suppressor p53 has the ability to recognize via its C-terminal domain DNA insertion/deletion mismatches consisting of one or a few extra bases on one strand (Lee, et al., 1995).
p53 binds to strand breaks in DNA (Lu and Lane, 1993; Nelson and Kastan, 1994); electron microscopy studies have shown that the C-terminal domain of p53 binds directly to ends of single-stranded DNA whereas the central domain of p53 binds to more internal segments (Bakalkin, et al., 1995). Short single strands considerably stimulate the sequence-specific binding of p53 to its cognate sites in supercoiled DNA and this recognition also involves the C-terminal domain of p53 (Jayaraman and Prives, 1995); a 29 nt segment of DNA known to arise by two endonuclease cuts during NER in mammalian cells around the lesion could stimulate p53 binding to DNA and might play some physiological function in the subsequent steps of repair (Jayaraman and Prives, 1995).
II. Differences in Biological Functions Between Wild-Type p53 and Tumor-Derived p53 Mutants
Tumor-derived mutant forms of p53 have lost their DNA sequence-specific binding capacities. For example the Trp-248 and His-273 mutants of p53 have poor DNA-binding abilities and are unable to activate transcription from constructs containing p53 binding sites (Farmer, et al., 1992).
A. Wild Type
Wild-type (wt) p53 tumor suppressor protein negatively regulates cell growth (Hollstein, et al., 1991; Prives, 1994). Whereas the wild-type p53 acts as a tumor suppressor, several of the mutant forms display oncogenic activities (Levine, 1993; Prives and Manfredi, 1993; Deppert, 1994). Although the wt p53 has been postulated to repress growth by activating genes that repress growth (p21), many of the mutant forms have lost their DNA sequence-specific binding and transcriptional activation capacities (reviewed by Zambetti and Levine, 1993).
According to one model (see Vogelstein and Kinzler, 1992), wt p53 is a positive regulator for the transcription of genes that by themselves are negative regulators of growth control and/or invasion. Indeed, p53 upregulates the genes of p21/CIP1/WAF1(El-Deiry, et al., 1993) and GADD45 (Kastan, et al., 1992) whose products interact with PCNA to inhibit its association with DNA polymerase d thus causing arrest in DNA replication (Waga, et al., 1994; Smith, et al., 1994). This feature of p53 that is central to its ability to suppress neoplastic growth is lost by mutations on p53 that result in loss of its ability to bind to DNA or to interact with other transcription protein factors (see also Farmer, et al., 1992; Kern, et al., 1992).
B. Mutant p53
Mutant p53 can transactivate genes that up-regulate cellular growth (Deb, et al., 1992; Dittmer, et al., 1993) such as PCNA (Shivakumar, et al., 1995), EGFR (Deb, et al., 1994), multiple drug resistance (MDR1) (Chin, et al., 1992; Zastawny, et al., 1993), and human HSP70 in vivo (Tsutsumi-Ishi, et al., 1995). These studies support the idea for an oncogene function of the mutant p53 protein compared with the tumor suppressor function of wt p53; mutation in the p53 gene may, thus, cause gain of new functions such as transforming activation and binding to a distinct class of promoters which are not normally regulated by wt p53 (Zambetti and Levine, 1993; Tsutsumi-Ishi, et al., 1995). At the same time appearance of mutations in the p53 gene result in the loss of function of the wt p53 (Zambetti and Levine, 1993).
The wild-type but not mutant p53 at low levels transactivates the human PCNA promoter in a number of different cell lines; the wild-type p53-response element from the PCNA promoter functions in either orientation when placed on a heterologous synthetic promoter; thus moderate elevation of p53 can induce PCNA, enhancing the nucleotide excision repair functions of PCNA (Shivakumar, et al., 1995). Whereas low levels of wild-type p53 activate the PCNA promoter, higher concentrations of wt p53 inhibit the PCNA promoter, and tumor-derived p53 mutants activate the promoter (Shivakumar, et al., 1995).
SV40 T antigen was unable to act as an initiator of SV40 DNA replication in vitro when complexed with p53 (Wang, et al., 1989); mutant p53 was unable to cause inhibition in the initiating functions of T antigen in vitro (Friedman, et al., 1990).
While the wt p53 is endowed with a 3'-to-5' exonuclease activity, associated with the central DNA-binding domain, and thought to function during repair, replication, and recombination; the 273 His mutant of p53 has lost the exonuclease activity (Mummenbrauer, et al., 1996).
C. Regulation of the p53 Gene
Very few studies on the regulation of the p53 gene are today available (Deffie, et al., 1993; Stuart, et al., 1995). The p53 gene is activated by the wt p53 but not by the functionally inactive mutant p53 protein; mobility shift assays and methylation interference have pinpointed the +22 to +67 region of the promoter of the p53 gene responsible for up-regulation containing an NF-κB response element and a p53-binding site at 10 of 11 nucleotides (Deffie, et al., 1993); it has been difficult to demonstrate direct binding of p53 to this regulatory region of its own gene and thus p53 may transactivate one or more transcription factors such as PRDII-BF1 (also known as MBP1 and HIVEP1), αA-CRYBP1, and AGIE-BP1 as well as NF-κB that bind the NF-κB response element (Deffie, et al., 1993).
p53 is down-regulated by Pax5 in early steps during embryogenesis is by interacting with a DNA control element within exon 1 of the p53 gene; at later stages of embryogenesis and in bone marrow cells Pax5 expression drops allowing the levels of p53 to rise; increased p53 was proposed to induce either apoptosis or B cell differentiation to plasma cells (Stuart, et al., 1995).
III. Gene Therapy Strategies Based on p53
A. Transfer of the p53 Tumor Suppressor Gene to Cancer Cells
Preclinical studies have shown that both viral and plasmid vectors able to mediate high efficiency delivery and expression of wild-type tumor suppressor p53 gene can cause regression in established human tumors, prevent the growth of human cancer cells in culture, or render malignant cells from human biopsies non-tumorigenic in nude mice. Inhibition in cell proliferation was observed in cell culture and in tumors after induction of p53 expression with adenovirus vectors (Bacchetti and Graham, 1993; Wills, et al., 1994). Intratracheal injection of a recombinant retrovirus containing the wt p53 gene was shown to inhibit the growth of lung tumors in mice nu/nu models inoculated intratracheally with human lung cancer H226Br cells whose p53 gene has a homozygous mutation at codon 254 (Fujiwara, et al., 1994). A number of other studies have shown suppression in tumor cell growth and metastasis after delivery and expression of the wt p53 gene (Diller, et al., 1990; Chen, et al., 1991; Isaacs, et al., 1991). A human clinical trial at M. D. Anderson Cancer Center uses transfer of the wild-type p53 gene in patients suffering with non-small cell lung cancer and shown to have p53 mutations in their tumors using local injection of an Ad5/CMV/p53 recombinant adenovirus at the site of tumor in combination with cisplatin (Roth, et al., 1996).
Delivery of the p53 gene to malignant human breast cancer cells in nude mice using DOTMA:DOPE 1:1 cationic liposomes (400 nmoles liposomes/35 mg DNA) resulted in regression (60% reduction in tumor cell volume) in 8 out of 15 animals treated; animals were receiving one injection every 10 days (Lesoon-Wood, et al., 1995). It was thought that wild-type p53 expression (tumor cells were expressing mutant forms of p53) upregulated p21 gene to inhibit cell growth by inhibition in cyclin-dependent kinases but also via induction of apoptosis preferentially in cancer cells.
B. Delivery of p53 to Prostate Cancer Cells
Prostate cancer cells have a mutated p53 gene: three of five prostate cancer cell lines examined (TSUPr-1, PC3, DU145) and one out of two primary prostate cancer specimens were found to harbor mutations altering the amino acid sequence of the conserved exons 5-8 of the p53 gene; transduction of the p53-defective cell lines with the wt p53 gene using lipofectin showed reduction in tumorigenicity assayed from reduced colony formation and the cells became growth arrested (Isaacs, et al., 1991). Although primary prostate tumors have few mutations in the p53 gene (Voeller, et al., 1994; Isaacs, et al., 1994), specimens from advanced stages of the disease and metastases as well as their cell lines frequently display mutations or deletions at both alleles of the p53 gene (Chi, et al., 1994; Dinjens, et al., 1994).
Introduction of the wt p53 or of the p21 downstream mediator of p53-induced growth suppression into a mouse prostate cancer cell line, deficient for p53, led to an association of p21 with Cdk 2; this interaction was sufficient to downregulate Cdk 2 by 65% (Eastham, et al., 1995). The p21 gene, driven by CMV promoter into an Adenovirus 5 vector, was more effective than the AD5CMV-p53 vector, under control of the same elements as p21, in reducing tumor volume in syngeneic male mice with established s.c. prostate tumors. Tumors were induced by injection of 2 million cells in each animal. These studies suggest that p21 expression might have more potent growth suppressive effect than p53.
Infection of the androgen-independent human prostate Tsu-pr1 cell line lacking functional p53 alleles with recombinant adenovirus vectors (replication-deficient) carrying the p53 gene under control of the CMV promoter resulted in expression of p53 and induced striking morphological changes: the cells were detached from the substratum, condensed, and exhibited breakdown of the nuclear DNA into nucleosome-size fragments characteristic of apoptosis; whereas control cells were able to elicit tumors in nude mice, the AdCMV/p53-infected cells failed to form tumors (Yang, et al., 1995).
Endocrine therapy is ineffective once the prostate cancer becomes androgen-independent; these cancers remain unresponsive to conventional chemotherapy. Androgen-independent and metastatic prostate cancers were established in athymic male mice by co-inoculation with the LNCaP human prostate cancer cell line and the MS human bone stromal cell line; these tumors became necrotic and were successfully eradicated by intratum oral injection of a recombinant p53/adenovirus; the p53 gene was driven by the CMV promoter and the SV40 poly(A) signal placed in the E1 region of Ad5 (Ko, et al., 1996). It was suggested that in addition to the tumor suppressor, apoptotic, and antiangiogenesis function of p53, tumor necrosis was induced by a bystander effect or a general immune response which attracted immune cells to cause tumor cell killing (Ko, et al., 1996).
However, a significant factor to be considered in these approaches is the competition of the wt p53 functions by the endogenous mu p53 expressed in tumor cells; optimal results will be expected if the endogenous mu p53 gene is inhibited with the simultaneous overexpression of the wt p53 gene.
As mutated forms of the p53 tumor suppressor gene are the most frequent in human tumors, down-regulation of the mutated endogenous p53 gene in prostate cancer cells and the simultaneous transfer and expression of a wild-type p53 gene able to undertake the tumor suppressor functions is expected to be of therapeutic value inducing apoptotic death to the prostate cancer cells.
C. Cancer Treatment by Transduction of Suicidal HSV-tk Gene Using Liposomes Followed by Treatment with Ganciclovir
The cells in a solid tumor are of different pheno- and geno-types; such differences among cells in the same tumor may include differences in ploidy, rearrangements, translocations, expression of oncogenes or tumor suppressor genes, and spectra of mutations among the various genes. It might therefore be an advantage simply to develop strategies for killing tumor cells rather than correct defective genes that led to the cancer phenotype; a package of additional mutations and/or changes may have accumulated in these cells.
A rather successful gene transfer approach results in the direct suppression of tumor growth by cytotoxic gene therapy. Cancer cells can be induced to be conditionally sensitive to the antiviral drug ganciclovir after their transduction with the thymidine kinase (tk) gene from the herpes simplex virus (HSV); ganciclovir is the 9-{[2-hydroxy-1-(hydroxymethyl)-ethoxy]methyl}guanine (Field, et al., 1983); it is converted by HSV-tk into its monophosphate form which is then converted into its triphosphate form by cellular enzymes and is then incorporated into the DNA of replicating mammalian cells leading to inhibition in DNA replication and cell death (Moolten, 1986; Borrelli, et al., 1988; Moolten and Wells, 1990).
It is only viral TK, not the mammalian enzyme, that can use efficiently ganciclovir as a substrate and this drug has been synthesized to selectively inhibit herpes virus replication (Field, et al., 1983); indeed, the mammalian TK has a very low affinity for this guanosine analog. The toxicity of ganciclovir is manifested only when cells undergo DNA replication and it is not harmful to normal nondividing cells. This treatment strategy has been used for hepatocellular carcinoma (Huber, et al., 1991; Su, et al., 1996), fibrosarcoma, glioma (Culver, et al., 1992, see below), adenocarcinoma (Osaki, et al., 1994) and prostate cancer (Eastham, et al., 1996).
This patent proposes other suicidal genes instead of HSV-tk such as the cytosine deaminase (CD) gene. The CD protein catalyzes the conversion of the prodrug 5-fluorocytosine (5FC) to 5-fluorouracil (5FU); treatment of cells, transfected with this construct, with 5FC results in the conversion of the 5FC into the antitumor drug 5FU into CD-positive tumor cells (Mullen, et al., 1992; Austin and Huber, 1993; Huber, et al., 1993; 1994; Richards, et al., 1995).
This approach has been used for the treatment of primary and metastatic hepatic tumors based on the overexpression of the suicidal CD gene under control of the regulatory regions of the tumor marker gene carcinoembryonic antigen (Richards, et al., 1995, see below).
SUMMARY OF THE INVENTION
A method for the treatment of a variety of human malignancies is claimed which consists of the following components:
(i) A wild-type (wt) p53 cDNA expression vector, mutagenized at the Pax5-binding site, under control of the CMV, β-actin, or other promoters, and human origins of replication able to sustain long term expression of the p53 gene; viral origins of replication which require viral replication initiator proteins such as T antigen for their activation are nor suitable for the transfer of the p53 gene because p53 protein interacts strongly with T antigen (Lane and Crawford, 1979). U.S. patent application Ser. No. 08/884,025 filed Jun. 27, 1997, now U.S. Pat. No. 5,894,060 issued Apr. 13, 1999 shows how to isolate origins of replication directly from human genomic DNA.
A.(ii) A Pax5 cDNA expression vector, the only suppressor of the p53 gene known (both of the wt and mutant p53 genes) interacting with a short (10 nucleotide) regulatory region within exon 1 of the p53 gene (Stuart, et al., 1995). A major drawback in p53 gene therapy is the inactivation of the wt p53 protein by the endogenous mutated forms of p53 which are overexpressed in tumors and which are able to tetramerize with wt p53 protein; the endogenous p53 genes will be suppressed by expression of Pax5, a potent transcriptional repressor of the p53 gene. The wt p53 cDNA vector is mutagenized at the Pax5-binding site and by consequence the suppressive effect of Pax5 protein cannot take place. It is important to suppress the endogenous mutant p53 gene expression and eliminate mutant p53 from the cancer cells to potentiate induction of apoptosis and tumor suppression
(iii) The herpes simplex virus thymidine kinase (HSV-tk) gene. The herpes simplex virus thymidine kinase (HSV-tk) suicide gene will be also included in combinations of p53 and Pax5 genes causing interruption in DNA synthesis after ganciclovir (GCV) treatment of the animal model and human patient; this is expected to increase the strand breaks in the cancer cells and to potentiate the tumor suppressor functions of p53 known to bind to strand breaks and to damaged DNA sites. Because of the combination of HSV-tk and p53 gene transfer, even expression of low therapeutic levels of the two proteins are expected to display and synergistic effect and potentiate tumor cell eradication for the reasons explained in this patent application.
Tumor cell mass in prostate cancer as well as in most other human cancers consists of an heterogeneous population of cells with respect to their ploidy, chromosomal translocations or deletions, and type of mutations in oncogenes and tumor suppressor genes. p53 tumor suppressor is mutated in over 70% of human cancers including prostate cancer; at early stages of carcinogenesis tumor cells may display mutations in one of the two p53 alleles and at both alleles at advanced stages. The endogenous mutated p53 interferes with the wild-type p53 (wt p53) function during gene transfer to cancer cells and it might be hard to achieve satisfactory expression levels and therapeutic effects with wild-type p53.
RATIONALE OF THE INVENTION
Gene therapy is a new era of biomedical research aimed at introducing therapeutic genes into somatic cells of patients (reviewed by Anderson, 1992). Two major obstacles prohibit successful application of somatic gene transfer: (1) the small percentage of transduced cells and (2) the loss of the transcription signal of the therapeutic gene after about 3-7 days from injection in vivo (reviewed by Boulikas, 1996a-e).
The first problem arises (i) from inability of delivery vehicles carrying the gene to reach the target cell surface (the vast majority of liposome-DNA complexes are eliminated from blood circulation rapidly); (ii) from difficulty to penetrate the cell membrane and (iii) to release the DNA from endosomes after internalization by cells; (iv) from inefficient import into nuclei. Our aim is to use stealth-cationic liposomes, which persist in circulation for days and concentrate in tumors. However, stealth liposomes are not taken up by cancer cells. Strategies are designed to enhance liposome internalization (PEG fall-off).
The second problem results from the loss of the plasmids in the nucleus by nuclease degradation and failure to replicate autonomously leading to their dilution during cell proliferation among progeny cells or by inactivation of the foreign DNA after integration into the chromosomes of the host cell. Our aim is to use human sequences able to sustain extrachromosomal replication of plasmids for prolonged periods. Viral origins of replication requiring T antigen or another viral initiator protein for their activation (Thierry, et al., 1995; Gassmann, et al., 1995) cannot be used for p53 delivery because of the strong binding of p53 to these proteins.
Transfer of the wild-type p53 gene has been successfully used to slow-down tumor cell proliferation in vivo and in cell culture in numerous studies (Diller, et al., 1990; Isaacs, et al., 1991; Chen, et al., 1991; Wills, et al., 1994; Fujiwara, et al. 1994) and intratumoral injection using adenoviral/p53 vectors has been shown to be effective against lung tumors in recent clinical trials (Roth, et al., 1996) and against prostate tumors on animal models (Ko, et al., 1996). The intratumoral injection method, however, may not be applicable to metastases often associated with late stages of cancer. Systemic delivery of the p53 gene and targeting of tumors in any region of the body might be a drastic treatment for cancer and its metastases. We claim strategies ameliorating four of the steps for somatic gene transfer using liposomal delivery of the wt p53 gene into a variety of human cancers in animal models and in patients to be tested in Clinical trials. These include: (i) concentration of the gene bullets into solid tumors, (ii) enhancement in uptake of p53/Pax5/HSV-tk plasmids by cancer cells, (iii) sustained expression of the genes using human origins of replication (ORIs) able to sustain episomal replication of plasmids for long periods in nuclei resulted in sustained expression of the transgenes, and (iv) potentiation of the p53 tumor suppressor activity by the Pax5 strategy, as well as in combination with HSV-tk and GCV.
We claim tumor regression and reduction in tumor mass volume of prostate and other cancers in animal models and in humans after delivery of a combination of the p53, Pax5, and HSV-tk genes using modified Stealth® liposomes followed by ganciclovir treatment.
Several experimental strategies for cancer treatment have been designed using p53 gene delivery; our novelty consists in that the endogenous mutant p53 forms, which are overexpressed in over half of human prostate malignancies (Isaacs, et al., 1991) especially those from advanced prostate cancer (Chi, et al., 1994; Dinjens, et al., 1994; reviewed by Boulikas, 1996e), are suppressed using the Pax5 expression vector (Stuart, et al., 1995). Mutated forms of p53 have amino acid substitutions mainly in their DNA binding domain but are still able to tetramerize with the wt p53 form; p53 acts as a tetramer and the presence of high levels of endogenous mutant p53 in human cancers cells interferes with the tumor suppressor functions of the wt p53 to be delivered.
Pax5 is an homeodomain protein which determines body structures during development; Pax5 is expressed at early stages of mammalian development and in the adult during differentiation in hematopoietic stem cells; p53 gene expression is eliminated by the Pax5 suppressor protein at early stages of development allowing cells to multiply fast in the developing embryo. Pax5 is switched off at later stages throughout adulthood allowing p53 to be expressed and exert its tumor suppressive functions and to regulate apoptosis especially in the hematopoietic cell lineage (Stuart, et al., 1995).
DETAILED DESCRIPTION OF THE INVENTION
We claim treatment of rat models of prostate cancer, mouse models of colon, breast and head and neck squamous cell carcinomas, and more important of a variety of human cancer patients by introduction of a combination of p53/Pax5/HSV-tk genes into the tumor cells. Our approach consists of two major parts: (i) the ability to target cancer cells (ii) effectiveness of our approach to kill cancer cells. A number of delivery systems are being used in somatic gene transfer, each associated with advantages and drawbacks. Recombinant adenoviruses do not replicate efficiently; recombinant murine retroviruses integrate randomly and are inactivated by chromatin surroundings; AAV integrates at chromosome 19 but needs helper adenovirus for infection. All have a maximum capacity of 3.5-7.5 kb of foreign DNA because of packaging limitations. Naked DNA is rapidly degraded (half-life 5 minutes) after systemic delivery (Lew, et al., 1995). Cationic liposomes do not survive in circulation beyond a heart beat and target mainly the endothelium of the lung, liver, and heart. So far, only Stealth® liposomes have been proven capable of concentrating in tumor sites (also in liver and spleen) and to survive for prolonged periods in blood circulation (e.g., one day compared with minutes for non-stealth neutral liposomes and a few seconds for cationic liposomes). However, stealth liposomes are not taken readily by tumor cells remaining in the extracellular space where they release their load over days after lysis; we propose to modify stealth liposomes with PEG which falls off (in collaboration with SEQUUS) exposing a partially neutral-partially cationic liposomal surface which would then enter the cell by poration or via caveolae avoiding degradation of the genes they engulf into lysosomes. Condensation of the DNA with histone H1, total histones, and HMGs will increase the nuclear import of the plasmid.
Having attained concentration and uptake of the gene bullets in solid tumors in animals with stealth liposomes, the second step is efficacy of our gene targeting approach. A number of studies support the idea that expression of the wt p53 gene in cancer cells in culture as well as in animals and clinical trials in vivo is of the most efficient means to kill cancer cells (Diller, et al., 1990; Chen, et al., 1991; Isaacs, et al., 1991; Bacchetti and Graham, 1993; Wills, et al., 1994; Fujiwara, et al., 1994). A human clinical trial at M. D. Anderson Cancer Center uses transfer of the wild-type p53 gene in patients suffering with non-small cell lung cancer and shown to have p53 mutations in their tumors using local injection of an Ad5/CMV/p53 recombinant adenovirus at the site of tumor in combination with cisplatin (Roth, 1996). The first results of this clinical trial are encouraging after intratumor injection of p53 (Roth, et al., 1996). However, local injection is not applicable to metastases often associated with advanced stages of malignancies; in particular, prostate cancer gives metastases to bones by a mechanism involving stimulation in prostate tumor proliferation by insulin-like growth factor I (IGF-I) which is especially secreted by bone cells. Therefore, the delivery system proposed here, able to concentrate into the tumor cell mass after systemic injection, is likely to treat not only the primary tumor but also its metastases.
The claims in this patent provide a potent gene therapy strategy applicable against a variety of human malignancies. The strategy is based on the suppression of the endogenous mutant p53 gene in cancer cells by the Pax5 expression vector; Pax5 expression will not affect the wt p53 gene expression because it lacks the Pax5 binding site located in the first exon of the p53 gene (Stuart, et al., 1995). Furthermore, the same strategy uses the herpes simplex virus thymidine kinase gene and treatment with the guanine analog ganciclovir expected to create strand breaks and disruption in DNA replication by arresting the replication forks; the incurred strand breaks are expected to bind wt p53 also expressed in the same type of cells thus potentiating the tumor suppressor function of p53 and the induction of the death pathway because of the accumulated damage on DNA.
Part of the claims are based on the ability to encapsulate plasmid DNA into Stealth® liposomes and the demonstrated concentration of this type of liposomes into tumors (SEQUUS patent). One major claim is to place all three genes (p53, Pax5, HSV-tk) under control of tumor-specific elements, such as the regulatory regions of the carcinoembryonic antigen (CEA), the BRCA1, the prostate-specific antigen (PSA), and other genes depending on the targeted tumor cell type.
Although by the year 2002-2003 the human genome project is expected to be completed we will be lacking information on the location of an estimated minimum of 450,000 regulatory regions; these include two enhancers or more and one promoter for each one of the 125,000 genes, plus about 50,000 ORIs, -one for every chromatin loop-, and an undetermined number of locus control regions, silencers, and boundary elements or MARs. A detailed understanding of the nature of regulatory regions in the postgenomic era and development of novel technologies for their isolation from nuclei of specific cell types would permit to pinpoint the regulatory regions among the 3×10 9 bp of human sequences. Relevant to this are efforts from our laboratory and other laboratories that culminated with the isolation of regulatory sequences from the human genome based on the MAR technology (Boulikas, et al., 1997). Such sequences will be used to increase the time of expression of p53 in animal tissues.
One of the strengths of this patent is that it uses human ORIs for the episomal replication of the genes. Episomal vectors using viral ORIs and T antigen to activate the viral ORI (e.g., Thierry, et al., 1995; Gassmann, et al., 1995) cannot be applied for the expression of p53 because p53 interacts with T antigen (Lane and Crawford, 1979; Linzer and Levine, 1979). Also, adenoviral vectors expressing E1B are not appropriate for the delivery of wt p53 because of the formation of an E1B-p53 complex leading to p53 inactivation (van den Heuvel, et al., 1990). Oncogenic viruses are believed to cause cancer by interaction of p53 with viral proteins, leading to p53 inactivation from inability to exert its tumor suppressive functions. Retroviruses are suitable for p53 delivery and have entered clinical trials (Roth, et al., 1996). However, retroviruses integrate randomly into the host genome and are inactivated by chromatin surroundings.
Transfer of the wt p53 along with Pax5 cDNA expression is expected to be more effective than transfer and expression of the wt p53 gene alone rendering the tumor cells amenable to apoptosis or programmed cell death.
Specific expression of the wt p53 in prostate cancer cell and its bone and other tissue metastases is effected using the promoter/enhancer/matrix-attached regions (MARs) of the prostate-specific antigen (PSA), a protein expressed specifically in prostate tumor but not in normal prostate cells; PSA is detected in the serum in humans in screening tests and is a powerful diagnostic tool for early as well as advanced stage of the disease. MARs are identified using the cloned gene fragments from the PSA gene and nuclear matrices, containing the minimal amount of MAR DNA in an in vitro MAR-binding assay.
We expect to determine the type of control elements among CMV, RSV, b-actin promoter, CHAT ORI, and SV40 promoter which is best to drive the p53 gene for each type of cancer in the animal model. We expect to find differences between different regulatory elements for each type of cancer because of relative differences in transcription factor levels required for the activation of these sequences among cell types (prostate, colon, HNSCC) (reviewed by Boulikas, 1994).
The proposed approach will only target dividing cells because of the use of HSV-tk and ganciclovir, and primarily vascularizing tumors because of the use of stealth liposomes. Thus, liver and spleen cells that are also reached by stealth liposomes will not be killed.
A. p53 versus P53 and Pax5
We claim that a combination of p53 with Pax5 is more efficient in killing cancer cells resulting in a more rapid shrinkage or eradication of the solid tumor than p53 vector alone. We expect that wt p53 expression will not be affected by expression of Pax5; this is because Pax5 protein is expected to suppress the endogenous mutated p53 gene in the tumor cells. These items will be tested by measuring quantitatively the wt p53 expressed in the tumor after p53 or p53 and Pax5 treatment of the animal. Similar studies will be done after transfection with HSV-tk in vivo. The GCV treatment is not toxic to the animal except for dividing cells transduced with HSV-tk (Culver, et al., 1992).
B. Preferential Expression of Suicidal Genes in Cancer Cells Using Promoters/Enhancers from Tumor-Specific Genes
A number of tumor-specific control regions are claimed to drive the expression of p53/Pax5/HSV-tk genes in tumor cells. Studies by others have shown targeting of hepatocellular carcinoma using the regulatory region from the tumor-specific a-fetoprotein gene to drive the Varicella zoster thymidine kinases gene (Huber, et al., 1991); treatment of primary and metastatic hepatic tumors based on the overexpression of the suicidal gene cytosine deaminase (CD) from E. coli under control of the regulatory regions of the tumor marker gene carcinoembryonic antigen (CEA) (Richards, et al., 1995). Regulatory sequences from the CEA gene (-322 to +111 bp) were also used to express the HSV thymidine kinase gene in pancreatic and lung neoplasms (Dimaio, et al., 1994; Osaki, et al., 1994).
It is claimed that this approach is applicable to target specific types of tumors.
The following example is intended to illustrate but in no way to limit the invention.
Materials and Methods
A. Construction of Expression Vectors
We have constructed efficient episomal vectors where the gene is under influence of the cytomegalovirus (CMV) immediately early (IE) promoter, Rous sarcoma virus (RSV) promoter, and MARs from the human CHAT gene (Boulikas, et al., 1997a,b; Boulikas and Hu, 1997) able to sustain about 100 to 1000-fold higher levels of expression of the luciferase reporter gene in vivo compared with commercially available expression vectors (e.g., pGL3-C of Promega Biotech, Madison, Wis.; pMAMneoLuc of Clonetech, Palo Alto, Calif.); These vectors include pLF, pdLF, pdLFd, pLFZ, and pL rsv F. The expression of the luciferase from pdLFd persists after cell culture transfection for more than 4 months, which is of the highest to be yet reported.
The plasmid is replicated in human cells as an episomal element (Boulikas, et al., 1997a).
A new plasmid is constructed containing: (i) the p53 gene under control of the cytomegalovirus immediately early (CMV IE) promoter and a strong ORI from the human genome arising from the ORI trap method; (ii) the Pax5 gene under control of the CMV IE promoter and the same ORI so as Pax5 will be subjected to the same regulatory constrains with p53 in nuclei of transfected tumor cells; (iii) the HSV-tk gene under control of the same elements.
Since only a small percentage of cells may be targeted resulting in the ultimate nuclear import of only a single plasmid from a mixture of three, engineering a larger plasmid containing all three genes together is a great advantage.
It is claimed that in order to measure the expression of the various transgenes in cell culture and in animal tissues and in the tumor of the animal, the DU145 cell line is used that has been shown to have a mutated form of p53 (Isaacs, et al., 1991). The Dunning rat model of human prostate cancer is used; rats are injected intravenously using the tail vein with 100 mg of the mixture of the three plasmids in equimolar amounts or the plasmid with all three genes after its condensation and encapsulation into stealth-cationic liposomes. p53 will be detected with commercially available antibodies.
It is claimed that the optimal conditions leading to regression of prostate tumors in rats and a variety of tumors in humans need to be determined in order to validate the therapeutic value of this approach. For example, control experiments using only two plasmid pairs (p53+Pax5 or p53+HSV-tk) and experiments where the relative stoichiometric amounts of the three plasmids are modified are expected to define the most effective conditions for cancer therapy.
In order to detect p53, Pax5, and HSV-tk in the tissues of the animal including the solid tumor the genes are constructed as fusion proteins with green fluorescence protein from the vector pGFP-N1 of Clontech. The proteins are detected under the fluorescence microscope by direct visualization of the cancer tissue.
Because the p53/GFP fusion protein might interfere with the tumor suppressor/apoptosis functions of p53, different constructs are made containing small peptides of about 7-10 amino acids as fusion products with the N- or C-terminus of p53. These peptides represent epitopes in proteins for which antibodies are available for their detection.
The genes are excised from commercially available plasmids or donations from laboratories: p53 and HSV-tk are from American Type Culture Collection (ATCC), Pax5 from Peter Gruss, Germany. Genes are placed under control of the CMV IE control element as described for construction of plasmid pLF (Boulikas, et al., 1997a). Control plasmids (pLF) containing the luciferase reporter gene are also used as well as inserts of the genes into the pLF plasmid; luciferase assays will reveal the distribution of expression in animal tissues.
B. Use of Human ORIs to Sustain Expression of Transgenes
Three key steps appear to be involved in effective gene transfer to somatic cells or to cells in culture: (i) vehicle for delivery (liposomal, adenoviral, retroviral, etc.) determining not only half-life in circulation, biodistribution in tissues, and efficacy of delivery but also the route through the cell membrane and fate in the nucleus; (ii) port of entrance to the cell, release of the DNA molecule from cytoplasmic compartments, and nuclear import; (iii) type and potency of regulatory elements for driving the expression of the transferred gene in a particular cell type including parameters that might determine integration versus maintenance of a plasmid or recombinant virus/retrovirus as an extrachromosomal element.
We propose strategies to test putative human origins of replication for their ability to sustain extrachromosomal replication of therapeutic plasmids for several weeks or months compared to a few days in current studies. We shall test initially the ability of the K19D fragment (513 bp) from the 3.6 kb clone isolated in our laboratory as the matrix-attached region and origin of replication of the human CHAT gene. This fragment has been inserted as one copy (pdLF) or two copies (pdLFd) in the pLF vector and has been shown to sustain episomal replication up to 4 months. In K562 cells in culture. Additional human sequences are available to be tested; these will be inserted into the plasmids carrying the p53, Pax5, and HSV-tk genes and the expression of p53 as well as tumor regression will be determined at time intervals, up to months, after systemic delivery of the plasmid with stealth-cationic liposomes.
C. Liposome Preparation
Liposomes can be prepared by various methods including reverse phase evaporation, dehydration-rehydration, detergent dialysis, and thin film hydration followed by sonication or extrusion through membranes of 400 down to 50-nm diameter pores. Liposomes are prepared either by ultrasonication or by sequential extrusion through 0.2, 0.1, and 0.05 mm membranes, 5 times each.
D. Plasmid Encapsulation
For plasmid encapsulation, spermine, histone-, or HMG-condensed supercoiled plasmid DNA are mixed with small unilamellar vesicles of average diameter of 60 nm obtained by ultrasonication; the mix will be frozen immediately using a dry ice/ethanol bath, lyophilized and hydrated. The degree of encapsulation will be controlled by 0.3% agarose gel electrophoresis able to determine the amount of free plasmid which is neither encapsulated nor complexed (Boulikas and Martin, 1996).
E. DLS Measurements
A Coulter N4M light (Coulter, Hialeah, Fla.) scattering instrument is used, at 90° angle, set at a run time of 200 sec, using 4 to 25 microsec sample time. The scan of the particle size distribution is obtained in 1 ml sample volume using plastic cuvettes, at 20° C. and at 0.01 poise viscosity.
F. Transfections and Luciferase Assays in Cell Culture
Prostate human cancer DU145 cells (from American Type Culture Collection) are cultured in RPMI 1640 medium supplemented with 9% fetal bovine serum, 0.1 mg/ml streptomycin, and 100 units/ml penicillin. Cell cultures are transfected by the direct addition of spermine-condensed DNA/liposome complexes in the presence of OPTI-MEM medium. The liposome formulation are DDAB:DOPE (1:1). At various times (1-7 days) posttransfection 0.5 ml cell culture (about 250,000 cells) is withdrawn into Eppendorf tubes, spun in a microfuge for 30 seconds, washed once in PBS, and the cell pellet is lysed directly into 0.5 ml luciferase lysis buffer (1% Triton X-100, 1 mM dithiothreitol, 2 mM EDTA, 100 mM Tris pH 8.0, 1 mM phenylmethylsulphonyl fluoride) and centrifuged for 2 minutes in Eppendorf tubes (13,000 g). 0.02 ml of the supernatant is assayed for luciferase activity using an automated luminometer, set at a 30 second reading time per well and a 3 second delay between wells and the Promega (Madison, Wis.) luciferase assay buffer kit. The samples are assayed for protein using the BioRad kit (BioRad, Richmond, Va.) and an automated 96-well reader of the colorimetric reactions. The luciferase values are normalized and expressed as relative luciferase units per mg protein.
G. Animal Injections and Luciferase/p53 Assays in Animal Tissues
0.3 mg plasmid is partially condensed in the presence of 0.03 mM spermine 0.15 mg total calf thymus histone at RT for 10 min in a total volume of 1 ml in the presence of 50 dextrose or 0.9% NaCl. The preparation is then complexed with 600 nmoles liposomes (DDAB:cholesterol 1:1) at RT for 1h.
Plasmids are encapsulated into Stealth® cationic liposomes DDAB:cholesterol:PEG-DSPE (10:10:1) with PEG-linked via S-S bonds to lipids (synthesized at SEQUUS Pharmaceuticals, Inc., Menlo Park, Calif.); these preparations are included in the place of PEG-DSPE for the preparation of Stealth®-cationic liposomes containing labile PEG chains.
The plasmid-spermine-liposome complex is divided into three equal parts and is injected (0.1 mg DNA per mouse; 0.4 mg per rat) to the tail vein of prostate cancer rat models or to the tail vein of Balb/c mice with established subcutaneous colon cancer tumors. At 2, 7, and 30 days postinjection, 3 animals per group will be anesthetized and perfused with buffer by cardiac effusion after cutting the portal vein to remove blood from tissues which interferes with luciferase assay. Two different methods will be used for luciferase assay in animal tissues. The solid tumor, lung, liver, spleen, and kidneys of the animal will be frozen in liquid nitrogen and ground to a fine powder; the ground tissue will be hydrated in buffers containing "TRITON" X-100 for cell lysis and will be processed similarly to the second method. According to the second method, the different organs will be homogenized in 0.5 ml phosphate-buffered saline (PBS) using a piston homogenizer for 1 min, will be incubated with collagenase to help dissolve the tissue; cells will be lysed by the addition of 0.2 ml of five times concentrated lysis buffer (see above) and transferred into Eppendorf tubes. Tissue cells will be further broken by three cycles of freeze-thawing using an ethanol-dry ice bath and a 37° C. water bath (10 min in each). Samples will be centrifuged at 13,000 g for 8 min and a 0.02 ml aliquot of the supernatant will be assayed for luciferase activity; another aliquot will be assayed for protein concentration as described above. p53 will also be determined using the monoclonal since p53 is under influence of the same control elements as luciferase/GFP, the convenient measurement of luciferase in animal tissues and in solid tumors will reveal the amount of expression of p53. This fact will be established and luciferase expression will be used as a diagnostic tool of p53 expression only; p53 expression will be determined independently of luciferase.
H. Treatment of Cancer Patients
Treatment of human cancer patients by intravenous infusion of 10 mg plasmid DNA encapsulated into liposomes is suggested until the toxicity and the efficacy of the dose are established on Clinical Trials This is about 30-fold lower than the doses used for laboratory animals. This simple fact necessitates the use of strong regulatory elements to demonstrate expression of therapeutic levels of the genes in human tumors.
I. Encapsulation of Mercaptoethylamine
Mercaptoethylamine is dissolved at 10 mg/ml in water to hydrate the dry film of stealth cationic lipids; the non-encapsulated drug is removed by dialysis against large volumes of 10 mM Tris pH 7.5. Stealth® liposomes loaded with mercaptoethylamine are injected to the same animals or human patients after the first infusion of the therapeutic plasmid in order to cause PEG hydrolysis. These are expected to be localized in the same tumor area releasing mercaptoethylamine and causing PEG to fall off from the surface of liposomes. The exposed DDAB cationic groups are expected to mediate membrane poration or uptake via caveolae.
J. Transduction of the Suicidal HSV Thymidine Kinase Gene Followed by Treatment with Ganciclovir
A rather successful gene transfer approach results in the direct suppression of tumor growth by cytotoxic gene therapy. Cancer cells can be induced to be conditionally sensitive to the antiviral drug ganciclovir after their transduction with the thymidine kinase (tk) gene from the herpes simplex virus (HSV). This treatment strategy has been used for hepatocellular carcinoma (Huber, et al., 1991; Su, et al., 1996), fibrosarcoma, glioma (Culver, et al., 1992), adenocarcinoma (Osaki, et al., 1994) and prostate cancer (Eastham, et al., 1996).
Microinjection of HSV-tk gene, under control of alpha-fetoprotein enhancer and albumin promoter, in a linear form flanked by the adeno-associated virus inverted terminal repeats into pronuclei of mouse embryos led to transgenic animals expressing preferentially HSV-tk into adult liver cells; these transgenic animals were used for the treatment of hepatocellular carcinomas (Su, et al., 1996).
Retrovirus-mediated transfer of HSV-tk was used to kill proliferating cells in rabbit models of proliferative vitreoretinopathy (PVR); PVR may ensue after retinal surgery or trauma. Injection into the vitreous cavity of rabbit dermal fibroblasts transduced in vitro with retroviral vectors carrying the HSV-tk gene was used to preferentially kill proliferating cells for PVR in rabbit models; all eyes received 0.2 mg GCV on the following day and on day 4; significant inhibition of PVR was observed thus providing a novel therapeutic strategy for this disease (Kimura, et al., 1996).
Subcutaneous tumors induced by injection of RM-1 (mouse prostate cancer) cells in mice followed by injection of HSV-tk in an adenovirus vector and treatment with ganciclovir for 6 days showed reduction in tumor volume (16% of control) and higher apoptotic index in tumor cells (Eastham, et al., 1996).
The bystander effect of the HSV-tk plus GCV system appears to be powerful and significant, circumventing the low efficiency of transduction in vivo with recombinant retroviruses. The low-level percentage of cells that can be transduced with a retrovirus can cause the elimination of a much larger percentage of proliferating cells in their surroundings (Kimura, et al., 1996).
We shall transfer the HSV-tk gene to solid tumors in animal models using liposomes in combination with p53, and Pax5, or alone (as a control). The regression in the volume of the tumor after GCV treatment will be measured. Also the expression of HSV-tk will be determined at 2, 7, and 30 days from delivery in the solid tumors and other organs using mRNA isolation from the tissue, reverse transcription to cDNA using the Clontech kit and PCR with primers specific for the viral gene.
K. Treatment with Ganciclovir (GCV)
Ganciclovir is the 9-{[2-hydroxy-1-(hydroxymethyl)-ethoxy]methyl}guanine (Field, et al., 1983); it is converted by HSV-tk into its monophosphate form which is then converted into its triphosphate form by cellular enzymes and is then incorporated into the DNA of replicating mammalian cells leading to inhibition in DNA replication and cell death (Moolten, 1986; Borrelli, et al., 1988; Moolten and Wells, 1990). It is only viral TK, not the mammalian enzyme, that can use efficiently ganciclovir as a substrate and this drug has been synthesized to selectively inhibit herpes virus replication (Field, et al., 1983); indeed, the mammalian TK has a very low affinity for this guanosine analog. The toxicity of ganciclovir is manifested only when cells undergo DNA replication and it is not harmful to normal nondividing cells. Systemic treatment of the animals with ganciclovir will be performed as described elsewhere (Huber, et al., 1991; Eastham, et al., 1996) using two IV injections per week using 0.05 mg/g body weight of the animal.
L. DpnI Assays on Hirt Extracts
Any cloned fragment of DNA can be tested for its efficacy to drive the autonomous replication of a bacterial plasmid after its introduction into cells in culture in transient transfection experiments. The method of preference for testing replication of a DNA fragment in higher eukaryotes is the DpnI-resistance assay on Hirt extracts (Hirt, 1967) at 48-72 post-transfection. According to this method, cells are lysed with SDS in the presence of about 0.5 M NaCl; the lysate is left at 0° C. for several hours. Under these conditions high molecular weight genomic DNA forms a large complex with the SDS-NaCl complex which can be removed following centrifugation at 13,000 to 25,000 g for about 30 min-1 h leaving the low size plasmid or viral DNA in the supernatant (Hirt, 1967). The plasmid DNA in the supernatant is extracted, digested with DpnI, the fragments are separated by electrophoresis on agarose gels, and blotted on nylon or nitrocellulose filters using the bacterial plasmid as a probe. DpnI-resistant plasmids are those replicated in eukaryotic cells and lacking methylation on adenine residues characteristic of molecules replicated in E. coli. It is only bacterially-made DNA that carries methylated A that is cleaved by DpnI.
However, identification of a genomic sequence that confers autonomous replication to a plasmid does not imply that the sequence functions as an origin of replication in vivo. In fact, only a fraction of yeast sequences that drive the autonomous replication of plasmids map to chromosomal origins of replication (Dubey, et al., 1991). It is believed, however, that most sequences capable of driving the extrachromosomal replication have sequence motifs characteristic of ORIs and could potentially be used as origins at a certain developmental stage or cell type.
At 72 h post-transfection the cells will be lysed and low molecular weight DNA will be isolated according to Hirt (1967). Hirt extracts will be linearized with BamHI or EcoRI and then digested with DpnI. This restriction enzyme cleaves fully methylated DNA (such as DNA grown in adenine methylase-positive HB101 E. coli) at the sequence G m ATC, but it is unable to cleave the GATC recognition site when the A residue is not methylated (i.e. when the DNA is replicated in mammalian cells). Linearized and DpnI-digested DNA fragments will be separated by electrophoresis on agarose gels, transferred to nitrocellulose or nylon membranes and hybridized using pBS as a probe. For this purpose, pBS will be labeled with a [ 32 P] ATP using the nick translation method of Amersham. The intensity of the DpnI-resistant band from each of the MAR/pBS plasmids will be compared to that of pBS alone.
M. DNA Sequencing
DNA sequencing is performed using an automated DNA sequencer (ALF system, Pharmacia, Piscataway, N.J.). All plasmid constructs are verified by sequencing.
N. p53 Expression
The level of expression of p53 is determined using monoclonal antibodies against p53 on filter membranes after transfer of the proteins extracted form rat prostate tumors on polyacrylamide gels. Western blot analysis is performed using the DO-1 no. SC-126 monoclonal antibody (Santa Cruz Biotechnology, Santa Cruz, Calif.) at 100-fold dilution (Westerman and Leboulch, 1996).
Additional Claims Overlapping with Other Patents
I. Delivery of the P53/Pax5/HSV-tk Genes to Solid Tumors with Modified Stealth Liposomes
We propose to target prostate and other cancer cells in animal models and humans using transfer of the wild-type (wt) p53 gene in combination with Pax5 and HSV-tk. p53 has been shown to be mutated and overexpressed in more than 50% of human malignancies; delivery of the wt-p53 gene to tumor cells has been shown to be a very effective treatment against cancer by inducing apoptosis or arrest in the cell cycle. However, the application of the method in vivo is inadequate, mainly due to failure of plasmids, retroviruses, or liposomes carrying the p53 gene to target preferentially solid tumors after systemic injection. Stealth® liposomes (coated with polyethyleneglycol, PEG) are known to extravasate through new blood vessels formed during angiogenesis and to concentrate in solid human tumors; however, they are not taken up by the cells. Cationic liposomes are cleared from blood circulation in 1 sec. (one heart beat) taken rapidly by endothelial cells. It is proposed here to use p53/Pax5/HSV-tk vectors encapsulated into stealth-cationic liposomes coated with PEG which is attached to lipids via disulfide bonds and a PEG fall-off strategy exposing cationic lipids on the surface of the liposomes, after concentration in tumors, to enhance uptake by poration of the cell membrane. | A method of treating cancer in a subject, by administering to the subject a combination of genes including wt p53, Pax5 and HSV-tk genes is disclosed. The method may involve subsequently treating the subject with ganciclovir. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a semiconductor device having an improved voltage controlled oscillator circuit formed by connecting a variable-capacitance element in combination with a bipolar transistor on a same single semiconductor substrate. More specifically, a variable-capacitance element is formed using a P layer as the base and an N layer as the collector among the NPN layers for forming a bipolar transistor.
2. Background Art
FIG. 3A shows an example of a conventional voltage control oscillator circuit formed by combining a bipolar transistor and a variable-capacity element formed on a same semiconductor substrate. FIG. 3B is a plan view showing the constitution of the variable-capacity element surrounded by broken lines in FIG. 3A ; FIG. 3C is a sectional view showing the side structure along B-B line in FIG. 3B ; and FIG. 3D is a small signal equivalent circuit of the variable-capacity element.
As these drawings show, when a bipolar transistor 10 and a variable-capacity element 30 are composed on the same semiconductor substrate 6 , as FIG. 3C shows, an N + layer 7 is formed as a contact on the semi-insulating semiconductor substrate 6 . An N layer 8 and a P layer 9 are formed thereon to be a collector and a base of an NPN transistor. A wiring 1 and a connecting wiring 3 are formed on the base layer 9 , and the electrodes 2 of the collector layer 8 are formed on the contact layer 8 , and wirings 5 for connecting the electrodes 2 to other circuit elements are formed on the both sides of the collector layer 8 . As FIG. 3B shows, the wirings 5 connect the both electrodes 2 mutually.
Furthermore, circuit elements shown in FIG. 3A are provided on the semiconductor substrate 6 to form the voltage control oscillator circuit. Specifically, a capacitor 12 for isolating direct-current components from external circuits is connected to the base of an NPN bipolar transistor 10 that forms the active part of the oscillator circuit, and each inductor 11 a and 11 b that determines the feedback quantity to the bipolar transistor is connected to the capacitor 12 and the emitter of the bipolar transistor 10 .
The wiring 5 connected to the collector layer 8 of a variable-capacity element 30 is connected to the inductor 11 a on the base side of the bipolar transistor. The serially connected body of the control power source 13 and the choke coil 14 for isolating the alternate-current components from a control power source 13 are connected also to the inductor 11 a . The reference numeral 15 denotes the output terminal of the oscillator circuit.
In such a constitution, the variable-capacity element 30 utilizes the phenomenon wherein the capacity generated between the base layer 9 and the collector layer 8 that form the PN junction varies corresponding to the variation of the voltage of the control power source 13 (e.g., see Japanese Patent Application Laid-Open No. 2000-124473).
The conventional semiconductor device is constituted as described above, and utilizes the variation of capacity generated between the base layer 9 and the collector layer 8 of the PN-junction diode as the variable-capacity element 30 . In this case, however, when a forward-direction voltage is applied to the above-described PN-junction diode, the depletion layer generated from the base layer 9 toward the direction of the contact layer 7 shrinks. Therefore, the collector region, which is from the lower end of the depletion layer to the contact layer 7 , expands in FIG. 3C . Accordingly, the resistance component 18 , shown in FIG. 3D , which is serially connected to the resistor 16 and the capacity component of the capacitor 17 of the diode, increases, and the Q value of the resonant circuit was lowered. Thus, the noise characteristics of the voltage-controlled oscillation circuit is deteriorated.
The object of the present invention is to solve the above-described problem, and to provide a semiconductor device that can form a voltage control oscillator circuit having a variable capacity element 30 , using PN junction, of a small resistance component serially connected to a capacity component on the same semiconductor substrate 6 with a bipolar transistor 10 .
SUMMARY OF THE INVENTION
According to the present invention, a semiconductor device having an improved voltage control oscillator circuit is provided. The voltage control oscillator circuit comprises in combination a variable-capacity element and at least a bipolar transistor formed on a same semiconductor substrate. The variable-capacity element includes a plurality of reversely serially connected PN junctions, and the plurality of PN junctions are formed by a single common collector layer and a plurality of separated base layers formed on the common collector layer. The capacity of the variable-capacity element is generated between respective base layers of the PN junctions with the common collector layer, and varies corresponding to the voltage applied to the common collector layer.
The semiconductor device according to the present invention is composed as described above, and the resistance component in the horizontal direction between respective base layers is decreased. As a result, the serial resistance component of the variable-capacity element is decreased.
Other and further objects, features and advantages of the invention will appear more fully from the following description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a plan view showing the constitution of a variable-capacity element in an embodiment of the present invention.
FIG. 1B is a sectional view showing the side structure along A-A line in FIG. 1A .
FIG. 1C is a small signal equivalent circuit of the variable-capacity element in the embodiment of the present invention.
FIG. 1D shows an example of the voltage control oscillator circuit formed by combining a variable-capacity element of the embodiment and an NPN bipolar transistor formed on the same semiconductor substrate in the embodiment of the present invention.
FIG. 2A is a characteristic diagram showing the aspect of change in the resistance component serially connected to the capacity component between the bases according to the embodiment of the present invention, in comparison with the aspect of change in the resistance component serially connected to the capacity component in a conventional PN-junction diode.
FIG. 2B is a characteristic diagram showing the phase noise characteristics of a voltage control oscillator circuit using a variable-capacity element in the embodiment of the present invention, in comparison with the phase noise characteristics of a voltage control oscillator circuit having a variable-capacity element in a conventional PN-junction diode.
FIG. 3A shows an example of a conventional voltage control oscillator circuit formed by combining a bipolar transistor and a variable-capacity element formed on a same semiconductor substrate.
FIG. 3B is a plan view showing the constitution of the variable-capacity element surrounded by broken lines in FIG. 3A .
FIG. 3C is a sectional view showing the side structure along B-B line in FIG. 3B .
FIG. 3D is a small signal equivalent circuit of the variable-capacity element of a conventional voltage control oscillator circuit.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
A preferred embodiment of the present invention will be described below referring to the drawings. FIG. 1A is a plan view showing the constitution of a variable-capacity element in the embodiment; FIG. 1B is a sectional view showing the side structure along A-A line in FIG. 1A ; FIG. 1C is a small signal equivalent circuit of the variable-capacity element; and FIG. 1D shows an example of the voltage control oscillator circuit formed by combining a variable-capacity element of the embodiment and an NPN bipolar transistor formed on the same semiconductor substrate.
The feature of this embodiment is that two or more electrically isolated island-like base layers are formed on a single collector layer to form two or more PN-junction diodes using semiconductor layers of a separate bipolar transistor; respective PN-junction diodes are reversely serially connected through a common collector layer; and a variable-capacitance element is constituted utilizing the phenomenon that capacitance between the terminals of PN-junction diodes varies with the voltage apply.
As FIG. 1B shows, an N+ layer 7 is formed as a contact on a semi-insulating semiconductor substrate 6 . An N layer 8 and a plurality of electrically isolated P layers 9 are formed thereon to form a plurality of reversely serially connected PN-junction diodes. The N layer 8 and P layers 9 correspond to a collector layer and a base layer among the NPN layers for a transistor. On each base layer 9 of the PN-junction diodes, each electrode 1 is formed, and wirings 3 and connecting wirings 4 are formed alternately on the electrodes 1 , as FIG. 1A shows, to form alternately intricate comb-like electrodes.
The electrodes 2 of the collector layer 8 are formed on the contact layer 7 , and wirings 5 for connecting the electrodes 2 to other circuit elements are formed on the both sides of the collector layer 8 ; and the wirings 5 are mutually connected, and choke coils 14 a and a control power source 13 are connected to this portion as shown in FIG. 1D .
Furthermore, other circuit elements shown in FIG. 1D are mounted on the semiconductor substrate 6 to form a voltage control oscillator circuit. Specifically, a capacitor 12 for isolating direct-current components from external circuits is connected to the base of an NPN bipolar transistor 10 that forms the active part of the oscillator circuit, and each inductor 11 a and 11 b that determines the feedback quantity to the bipolar transistor is connected to the capacitor 12 and the emitter of the bipolar transistor 10 .
Since the basic constitution of the voltage control oscillator circuit is similar to the circuit shown in FIG. 3A , the same parts are denoted by the same reference numerals, and the description thereof is omitted; however, the aspects different in FIG. 1A are that the variable-capacity element 31 is formed of a plurality of reversely serially connected PN-junction diodes described in FIGS. 1 A and 1 B, and the wirings 3 and choke coils 14 b are connected to the inductor 11 a connected to the base side of the bipolar transistor 10 as shown in FIG. 1D .
In FIG. 1C , the reference numeral 16 denotes a resistance component of the PN-junction diode; 17 denotes the capacity component of the same PN-junction diode; 18 denotes a resistance component of the neutral semiconductor region in the vertical direction from the end (lower end) of the depletion layer to the contact layer 7 , produced from the base layer 9 side toward the direction of the contact layer 7 in FIG. 1B . The neutral semiconductor region extends from the end of the depletion layer to the contact layer 7 of the PN-junction diode, and the reference numeral 19 denotes a resistance component of the neutral semiconductor region in the horizontal direction. That is the resistance component inversely proportional to the cross-sectional area of the collector layer 8 connected to the wirings 3 and 4 , i.e., the product of “the distance from the end of the depletion layer to the contact layer 7 ” and “the length of the electrode 1 in the up-and-down direction” shown in FIG. 1A . The reference numeral 20 denotes the resistance of the contact layer 7 ; and 21 denotes the contact resistance of the collector electrode 2 .
FIG. 2A shows a characteristic diagram comparing the aspect of change in the resistance component serially connected to the capacity component between the base wirings 3 and 4 when the base wirings 3 and 4 are grounded, and a voltage of the control power source 13 is applied to the collector wiring 5 , with the aspect of change in the resistance component serially connected to the capacity component when the same capacity is realized by a conventional PN-junction diode.
It is seen that in comparison with the conventional variable-capacity element 30 using the PN-junction diode, the variable-capacity element 31 in this embodiment has a lower control-voltage dependence of the resistance component serially connected to the capacity component. This is because in the conventional variable-capacity element 30 using the PN-junction diode, the width of the depletion layer shrinks in the vertical direction in FIG. 3C when a forward bias is applied between the base layer 9 and the collector layer 8 , and the resistance component 18 in the vertical direction from the end of the depletion layer of the PN junction to the contact layer 7 increases, as is seen from FIG. 3D , so that the resistance component 18 serially connected to the capacitor is increased. In the variable-capacity element 31 in the present embodiment, N-type collector layers 8 and N + -type collector contact layers 7 of the two or more PN-junction diodes are common. The width of the depletion layer shrinks in the vertical direction in FIG. 1B when a forward bias is applied between the base layer 9 and the collector layer 8 , and the resistance component 18 in the vertical direction of the neutral semiconductor region from the end of the depletion layer to the contact layer 7 of the PN junction is increased similarly to the conventional variable-capacity element. However, since the resistance component 19 in the horizontal direction between the wirings 3 and 4 is inversely proportional to the cross-sectional area determined by the product of “the distance from the end of the depletion layer to the contact layer 7 ” and “the length of the electrode 1 in the up-and-down direction in FIG. 1 A”, the above-described cross-sectional area expands when the width of the depletion layer shrinks. That results in decrease in the resistance component 19 , and the reduction of the control-voltage dependence of the serial resistance component.
This effect utilizes decrease in the resistance component 19 in the horizontal direction. Therefore, if the electrodes 1 of the facing comb-shaped base layers 9 are disposed as shown in FIG. 1A , and the electrodes 2 of the collector layer 8 are disposed on both sides as shown in FIG. 1A so as to widen the width of the base layers 9 (the length of the electrode 1 in the up-and-down direction in FIG. 1A ), or alternatively if width in the facing directions of two or more base layers 9 (wirings 3 and 4 ) generating capacity as shown in the sectional view of FIG. 1B , then the resistance 19 in the horizontal direction can be effectively reduced.
FIG. 2B shows a characteristic diagram comparing the phase noise characteristics of a voltage control oscillator circuit using a variable-capacity element 31 in the present embodiment with the phase noise characteristics of a voltage control oscillator circuit having a variable-capacity element 30 utilizing the capacity variation between the anode and the cathode obtained by applying a voltage to a conventional PN-junction diode. It is seen from this characteristic diagram that the noise characteristics of the voltage control oscillator circuit using a variable-capacity element 31 in the present embodiment are superior to those using the conventional base-collector capacity element 30 .
In the above-described embodiment, an example of the serial feedback-type oscillator circuit wherein a variable-capacity element 31 is connected to the base terminal of a bipolar transistor 10 is shown. Alternatively, the variable-capacity element 31 may be directly connected to either the collector terminal or the emitter terminal of the bipolar transistor 10 . Further, a parallel feedback-type oscillator circuit may be obtained wherein the variable-capacity element 31 is connected between any two of the emitter, the base, and the collector terminals of the bipolar transistor 10 . The same action and effect may be expected from these variations.
In the above-described embodiment, an example is shown wherein a choke coil 14 a is used as an element for isolating alternate-current components from the control power source 13 . It will be obvious that a resistor may be used as an element for isolating alternate-current components from the control power source 13 .
The present embodiment is constituted as described above, and a variable-capacity element having little parasitic resistance component can be realized using a bipolar transistor structure. By combining the variable-capacity element and the bipolar transistor on the same semiconductor substrate, a voltage control oscillator circuit having low noise can be obtained.
Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within the scope of the appended claims the invention may by practiced otherwise than as specifically described.
The entire disclosure of a Japanese Patent Application No. 2004-201354, filed on Jul. 8, 2004 including specification, claims, drawings and summary, on which the Convention priority of the present application is based, are incorporated herein by reference in its entirety. | A semiconductor device having an improved voltage control oscillator circuit is provided. The voltage control oscillator circuit includes, in combination, a variable-capacitance element and at least one bipolar transistor on a single semiconductor substrate. The variable-capacitance element includes reversely serially connected PN junctions, and junctions are formed by a single common collector layer and separated base layers on the common collector layer. The capacitance of the variable-capacitance element is generated between respective base layers of the PN junctions with the common collector layer, and varies in correspondence with the voltage applied to the common collector layer. | 7 |
BACKGROUND OF THE INVENTION
The invention relates to a treatment for reducing and/or preventing HIV from infecting cells. More specifically, the invention involves preventing the HIV virus from replicating by using Leukemia Inhibitory Factors (“LIF”) to bind with its own specific receptors on T-lymphocytes or monocyte derived macrophages to prevent HIV replication.
SUMMARY OF THE INVENTION
Although the discovery of tropism specific HIV entry inhibitors began with Beta-chemokines, other factors with more global inhibitory function such as CAF (a CD8 derived antiviral factor)have been extensively studied but not unequivocally identified. The placenta remains an organ of intense study because vertical HIV transmission occurs in only 14-40% of untreated pregnancies despite exchange of blood between mother and fetus. A strong type 2 cytokine milieu (IL-4, IL-10) has been found in placentas from non-transmitting placentas that is significantly reduced in transmitting placentas. Associated with the type 2 cytokine response, it has not been found that non-transmitting placentas produce high levels of leukemia inhibitory factor (LIF). Thus, it has been determined that LIF is a potent inhibitor of HIV production with laboratory and primary isolates of HIV. Consequently, it has been found that LIF is involved in inhibition of both replication and vertical HIV transmission. As such, LIF may be used as a systemic treatment of infected individuals.
DESCRIPTION OF THE DRAWINGS
FIG. 1 shows the relationship between LIF concentration and fraction of virus produced by untreated controls infected with an HIV isolate that uses the CXCR4 receptor of a cell; and
FIG. 2 shows the relationship between LIF concentration and fraction of virus produced by untreated controls infected with an HIV isolate that uses the CCR5 receptor of a cell.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Set forth below is a description of what are currently believed to be the preferred embodiments or best examples of the invention claimed. Future and present alternatives and modifications to the preferred embodiments are contemplated. Any alternates or modifications in which insubstantial changes in function, in purpose, in structure or in result are intended to be covered by the claims of this patent.
In the absence of antiretroviral therapy 14%-40% of HIV infected women transmit HIV to their infants indicating that the placenta may play a protective role in vertical transmission. To study placenta derived factors that may contribute to protection, extensively washed, fresh or snap frozen placentas were obtained from six non-transmitting women and five transmitting women naive to antiretroviral therapy during their pregnancy and placentas from 3 HIV seronegative women. To identify blocks to HIV penetration or replication in placentas, total DNA or RNA from these placentas was applied to real time quantitative PCR or RTPCR gene panels consisting of HIV gag DNA, HIV gag mRNA, type 1, type 2, and inflammatory cytokines, chemokines, chemokine receptors, and LIF. Expression of HIV gag mRNA was found in 4 of 5 (80%) of term transmitting placentas (TT) and only 2 of 13 term non-transmitting placentas (15%). The average number of HIV mRNA copies in the TT placentas was 510/100,000 cells and the average number of copies of HIV mRNA in TNT placentas was less than the sensitivity of the assay which is 20 copies/100,000 cells. No significant difference was found in the number of placentas containing HIV DNA as HIV DNA was detected in 5 of 5 TT placentas (100%) and in 8 of 10 (80%) of TNT placentas, respectively. The average number of HIV DNA copies in TT placentas was 29.7 copies per 100,000 cells and the average number of copies in TNT placentas was 17.9 copies per 100,000 cells (p=NS). These results indicate that TNT placentas inhibit HIV replication better than TT placentas without significantly affecting the level of infected cells.
Cytokines have been shown to either increase or decrease HIV replication and the placenta is known to produce a multitude of type 1, type 2, and inflammatory cytokines. To determine if the expression pattern or quantity of cytokine expression might explain the significant difference in HIV gene expression in transmitting and non-transmitting placentas, cytokine message and protein in tissue sections were quantified by quantitative real time RTPCR and assisted computerized image analysis. There was a statistically significant elevation of type 2 cytokine (IL-4, IL-10) mRNA and protein expression relative to type 1 cytokine (IL-2) expression in placental tissue from non-transmitting placentas (p<0.02). In contrast, transmitting placentas showed significantly higher incidences of type 1 cytokine expression both at the mRNA and protein level (p<0.05) while type 2 cytokines were significantly upregulated in non-transmitting placentas compared to transmitting placentas (p<0.01). This type 2 cytokine upregulation did not correlate with superimposed chorioamnionitis, villitis, or vasculitis in any of the placentas.
To determine if LIF expression in HIV infected placentas followed the same cytokine regulation pattern as in uninfected placentas, I quantified LIF and mRNA and protein in all placentas. LIF mRNA was significantly upregulated in TNT placentas compared to TT placentas while quantification of LIF protein expression paralleled the mRNA expression. LIF mRNA and protein expression did not significantly differ from the production in normal placentas. The defective production of LIF in the TT placentas may explain the increase in spontaneous abortion in a certain population of HIV infected women with placental cytokine dysregulation.
The effects of IL-4 and IL-10 on HIV infection and replication are well established. To test the effects of LIF on HIV, dose dependent inhibition experiments with a 4-log range of LIF concentrations were performed from 0.1 pg/ml to 100 pg/ml. LIF inhibited the CCR5-using (R5) HIV Bal, the CXCR4-using (X4) HIV Lai, and the dual tropic (R5X4) HIV-1 ME46 with an IC50 of 0.5 pg/ml. Potent inhibition of HIV replication was detected in both T-lymphocytes and monocyte derived macrophages using simultaneous immunophenotyping/ultra sensitive in situ hybridization and flow cytometry. As shown in FIGS. 1 and 2, 100% reduction of virus production may be achieved through use of LIF. This demonstrates that LIF treatment may be used to inhibit the replication of the HIV virus in both infected and uninfected cells. First, LIF may be used as a systemic immune-based therapy for all HIV infected individuals by inhibiting the further replication of the virus in the host cells. This may be accomplished by inoculating and individual with LIF. Second, LIF may be used to prevent infection with the HIV virus through inoculation with LIF prior to exposure to the HIV virus. LIF is particularly suitable for use in human since it is a protein that is naturally found in humans.
Untreated controls infected with all isolates demonstrated high levels of both early and late reverse transcripts. The data suggest that the anti-viral activity of LIF takes place prior to reverse transcription; an activity that is distinct from CAF since CAF does not affect reverse transcription or proviral integration.
Infection of peripheral white blood cells from uninfected individuals were treated. A TCID50 of: 1000 for HIV Bal, 10,000 for HIV Lai, and 1000 for HIV ME46 was used to infect 107 PHA-stimulated peripheral blood mononuclear cells. The concentrations of recombinant, ultrapure (>99%) leukemia inhibitory factor were 0.01 pg/mL, 0.05 pg/mL, 1.0 pg/mL, and 10 pg/mL. All strains were tested in quadruplicate wells in three separate experiments. To correlate the replication endpoint concentration with a formal percent inhibitory concentration, we obtained that absolute p24 antigen content for each drug concentration. The concentration of drug that reduced the p24 antigen value of the control well by 50% (IC50) was calculated using non-parametric regression analysis and was found to be 0.5 pg/ml for all HIV isolates tested as shown in FIGS. 1 and 2. As also shown, LIF concentration at about 1 pg/ml show no viral replication.
Based upon the above, complete HIV replication in a host may be acheived by attaining LIF concentrations in blood or other tissues at about 1 pg/ml, depending bioavailability. This concentration is particularly useful since it is approximately 1000 fold less than other known HIV inhibitors such as RANTES, MIP-1alpha, and/or MIP-1beta, among others.
Dosages of LIF may be admisinstered in a number of ways known to those of skill in the art. For example, LIF may be administered by injection, orally, topically, mucosally, and in other ways. LIF has already proven to be safely administered to research animals to promote production of cells from the bone marrow. Recombinant LIF was obtained from Phar Mingen.
While the invention has been described with reference to the preferred embodiments thereof, it will be appreciated that numerous variations, modifications, and alternate embodiments are possible, and accordingly, all such variations, modifications, and alternate embodiments are to be regarded as being within the spirit and scope of the invention. | The present invention concerns a method for inhibiting HIV replication in a cell by binding Leukemia Inhibitory Factors (“LIF”) LIF to its receptor in a cell to inhibit HIV replication within the cell. In addition, the present invention concerns a method for preventing uninfected individuals from infection with HIV by administering a dosage of LIF to prevent establishment of HIV infection. The present invention also provides a method of treating HIV infected individuals by administering a dosage of LIF to prevent disease progression. | 0 |
FIELD
[0001] The disclosure relates generally to clinical data analysis on a social networking service and, in particular, to a system and method for sharing, analyzing and consolidating medical data in a social network.
BACKGROUND
[0002] Presently, Medical Social Networks are seen as a means to connect to people with similar health concerns. By using this platform patients can get information about the other patients having same medical conditions and doctors can also use this platform to communicate with other doctors and patients. Most medical social networks are meant for the doctors or professionals or physicians to connect with others including unknown persons on professional and personal front.
[0003] One problem with such medical social networking sites is that they are not seen as a platform to share a clinical data. Clinical data are regarded most sensitive data and handling of this data requires utmost care. At the moment no methodology ensures that patient or clinical data are shared safely on the medical social networks. Social networks are deemed to be an unsafe platform to share personal information.
[0004] Another problem with such medical social networking sites is that the information provided by its members is not wholly trusted. One has to ensure the Authenticity of its members. It is possible that people with vested interest become a part of the network posing as medical professionals or patients, trying to promote products and drugs. Few social networks only for physicians allows only verified US Doctors to connect with each other. However we as of today, we do not have a medical social network that connect verified patients, doctors and caretakers coming together at one platform.
[0005] Yet another problem with such medical social networking sites is that they do not provide a platform to do medical research. Like any other form of research, clinical research is also driven by the availability of authentic, large clinical data. Practitioners and researchers today are restricted to the data they have their hands on which is neither of good quantity nor of good quality. As of today, we have no means of creating a global database that gathers information from patients across the globe and maintained for use of researchers, patients and professionals, simultaneously safeguards the interest of patients.
[0006] Still another problem with such medical social networking sites is that they do not provide any tool to connect people in emergency situations.
[0007] In view of the foregoing discussion, there is a need for designing a social network platform that ensures all users of the network including professionals, patients and caretakers are verified, used to share clinical data, prevents the misuse of personal information, gathers medical data across the globe in a secured and structured manner and make it available to patients or professionals or researchers for better understanding of diseases and treatments, used as tool for connecting to people in emergency situations.
SUMMARY
[0008] The shortcomings of the prior art are overcome and additional advantages are provided through the provision of a method and system as described in the description.
[0009] The present disclosure solves the limitations of existing techniques by providing a system and method for sharing, analyzing and consolidating medical data in a social network.
[0010] In one embodiment, the disclosure provides a system for sharing, analyzing and consolidating medical data in a social network. The system includes an authentication module which is configured to verify one or more data associated with one or more participants applied to become a member in the medical social network. The system also includes an access control configuration means by which the accessibility of data associated with a member of the social network is restricted. The system provides a platform for doing statistical analysis of data available in the social network. The system further provides an emergency service facility to its members comprising: listing names of one or more medical professionals or caregivers to be contacted in case of an emergency, sending an alert message to the medical professionals or care givers.
[0011] In one embodiment, the disclosure provides a method for sharing, analyzing and consolidating medical data in a social network. The method includes receiving request to become a member of the social network and classifying the participants as patients, medical professionals or caregivers based on one or more data entered by the participants. Further, sending the data entered by the participants to a medical professional registration body for verification of a medical professional, to a certified medical professionals for verification of a patient and to one or more member patients or one or more member medical professionals in case of a caregiver. The method further includes restricting accessibility of data associated with a member of the medical social network to one or more contacts in the medical social network based on an access control configuration of the member data. The method also includes analysing a plurality of medical data available at the medical social network using one or more statistical parameters by one or more researchers. The method further includes masking one or more personal information of one or more members of the social network in one or more query results. The method also includes sending an alert message to one or more medical professionals in case of an emergency.
[0012] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] Various embodiments of the invention will, hereinafter, be described in conjunction with the appended drawings provided to illustrate, and not to limit the invention, wherein like designations denote like elements, and in which
[0014] FIG. 1 illustrates an exemplary environment of an online social network;
[0015] FIG. 2 depicts an exemplary environment of an online social network along with various modules for sharing and analyzing medical data in the social network;
[0016] FIG. 3 is a flowchart for sharing, analyzing and consolidating medical data in a social network, in accordance with an embodiment of the present invention;
[0017] FIG. 4 depicts the authentication process of the members in the social network;
[0018] FIG. 5 a is a flowchart for restricting the access of data in social network within the primary contact;
[0019] FIG. 5 b is a flowchart for restricting the access of the data in social network outside the primary contact;
[0020] FIG. 6 is a flowchart for analyzing data in the social network;
[0021] FIG. 7 depicts the emergency service available in the social network.
DETAILED DESCRIPTION
[0022] The foregoing has broadly outlined the features and technical advantages of the present disclosure in order that the detailed description of the disclosure that follows may be better understood. Additional features and advantages of the disclosure will be described hereinafter which form the subject of the claims of the disclosure. It should be appreciated by those skilled in the art that the conception and specific embodiment disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the disclosure as set forth in the appended claims. The novel features which are believed to be characteristic of the disclosure, both as to its organization and method of operation, together with further objects and advantages will be better understood from the following description when considered in connection with the accompanying figures. It is to be expressly understood, however, that each of the figures is provided for the purpose of illustration and description only and is not intended as a definition of the limits of the present disclosure.
[0023] Exemplary embodiments of the present disclosure provide a system and method for sharing the medical data in a social network where the access of the personal information, such as clinical data, is restricted and data privacy is maintained. The disclosure also provides the system and method of data analysis by the members of the social network and also by the researcher using the social network's medical database. In addition, the system and method provides the emergency service to its members to send the alert message in case of emergency.
[0024] FIG. 1 illustrates an exemplary environment of an online social network. According to the illustration in FIG. 1 , a social network server 102 is connected to a client device 106 over a computer network 104 . The network 104 can be any network over which information can be transmitted between devices such as internet, intranet, Virtual Private Network (VPN), Local Area Network (LAN), Wide Area Network (WAN) and the like. A client device 106 may include, but is not limited to, a desktop computer, a laptop, a mobile computing device and the like.
[0025] FIG. 2 depicts an exemplary environment of an online social network along with various modules for sharing and analyzing medical data in the social network. More particularly, in FIG. 2 the social network server 102 includes an authentication module 202 configured to authenticate one or more members of the social network and helps to create an authentic source of medical database that can be made available for research and analytics. The social network server 102 also includes an access control or privacy setting module 204 which ensures the data privacy of the members of the social network. Access control or privacy setting module 204 restricts the visibility of the data entered by a particular member to other members. Access control or privacy setting module 204 can be configured for each primary level contact and also for second and third level contacts. The server 102 also includes a statistical analysis module 206 which helps one or more members and nonmember researchers to run the statistical analysis of data available in the social network. Nonmember researcher can login to the Researcher's analysis platform and run statistical analysis of medical data available in social network. According to one embodiment of the invention the social network server 102 includes an emergency service module 208 which helps the members of the social network to contact with one or more medical professionals in case of emergency situation. Members need to subscribe to avail the emergency service.
[0026] FIG. 3 is a flowchart for sharing, analyzing and consolidating medical data in a social network, in accordance with an embodiment of the present invention. The method includes, receiving the request of the participants to become a member of the social network, at 302 . Thereafter, at 304 , the participants are classified as patients, medical professionals and caregivers. After classifying the participants, at 306 , the system sends the user information to authorized body for verification. If the participants are not authorized as genuine user by the authorized body then the service is not available to them. If the participants are authenticated by the authentication body as genuine user then the participants are allowed to login to the server as a member and they need to enter the data regarding their personal information as well as clinical data or experience and specialization in a pre-existing template. After login, at 308 , members are required to configure access control settings to restrict the accessibility of the member data. The members can configure access control for each individual. After that, at 310 , the members can analyze the data across the primary network or across different communities or across social network based upon the query. The data analysis across the community and social network is a paid service. Data analysis is also possible for the non member researchers upon login in the Researcher's analysis platform. The system masks the personal information in the query results, at 312 . After analyzing the data the members may select to login the emergency service. If the members opt for emergency service then, at 314 , they have to write down the names of the contacts to be contacted in case of emergency. In accordance with an embodiment of the present invention, at 316 , an alert message is sent to the specified contacts in case of emergency.
[0027] FIG. 4 depicts the authentication process of the members in the social network. As shown in the figure, the participants 402 send the request to the social network to become a member, at 304 . After receiving the request the system classify the participants as patients, at 404 , or as medical professionals, at 406 , or as caregivers, at 408 . Thereafter, at 410 , the patients are verified by medical professionals by whom they are being advised. The medical professionals are verified by a medical professional registration body upon request and they verify the personal details submitted by the medical professionals, at 412 . Further, at 414 , caregivers are verified by member medical professionals or member patients. After getting verified, at 416 , the members can join the social network.
[0028] According to an embodiment of the present invention the members can set the access control of data associated with them for individuals of primary contact as well as for second and third level contacts. In this system access control settings with respect to every connection are set at the time of establishing the contact. Access control settings are a part of the connection procedure. FIG. 5 a is a flowchart for restricting the access of data in social network for individual in primary contact. In step 502 , the members connect to the social network. In step 504 , the member opens new invite or opens request to connect sent by another member. In step 506 , the members are required to select the privacy setting option. In step 508 , the members select the data which they want to share with a particular contact. Only those data are visible by the contacts which are permitted by the members. The data associated with a member is divided into three data levels such as primary data, secondary data and tertiary data. The primary data includes the name and place of a member; secondary data includes more specific information such as address, email, phone number and primary health concern in case of member patients or specialization in case of member medical professionals; tertiary data includes more critical information such as, the clinical data in case of member patients, personal recommendations and experiences in case of member medical professionals and member caregivers. The clinical data is put on specific templates designed by experts so that the data gathered has a uniform structure.
[0029] If any member does not select a particular data from primary, secondary or tertiary level for sharing with a particular contact then that contact cannot see that data of the member. In step 510 , the members are required to apply the access control or privacy setting they have configured for a particular contact. In step 512 , the members send the friend request or accept the friend request subject to the access control configuration.
[0030] FIG. 5 b is a flowchart for restricting the access of the data in social network outside the primary contact. As the figure shows, in step 502 , the members connect to the social network. In step 514 , the members open the privacy setting for second and third level contacts. Thereafter, in step 506 , members select the data from the primary, secondary and tertiary level that can be shared with the contacts in second or third level contacts. In step 516 , members select the contact level such as second contact level and third contact level. In step 510 , members are required to apply privacy setting.
[0031] FIG. 6 is a flowchart for analyzing data in the social network. To start with, at 602 , the members login to the social network. If any researcher who is not the member of the social network want to access the data available in the social network can access the data by login into the researcher's analytics platform after paying the subscription fee, at 604 . After login in to the system the members or researchers enter the data query, at 606 . Data analysis uses the data available in the primary contact level as well as data available across any community and social network. If the member uses the community or social network data outside the primary contact level they are required to pay the fees for that. The queries include but not limited to list queries, number queries, and percentage queries. In list queries the list containing names or data values pertaining to the parameter of interest is displayed; in number queries the number of instances matching with the query is displayed; in percentage queries the percentage of the matching instances in the data is displayed. To aid basic statistical research the basic statistical parameters such as average, mean, median or variation are supported in the queries. In step 608 , the system retrieves the query results but this result is not displayed to the members or researchers. The data is displayed to the members or researchers only after masking the personal information in the query results, at 610 . The basic idea is to mask the information if the data sought pertains to personal identity. The masked data is sent to the members as the query result, at 612 . In the masked data personal information is replaced by false personal data. The data is masked by using various masking techniques commonly known by an ordinary person skilled in the art. As above various examples of masking techniques may include, but not limited to, shuffling, encryption, and substitution. Shuffling may have various schemes, for example, every “A” with “Z” or every “Z” with “A”. In encryption there is encryption logic for changing every value under the sensitive information. Substitution may have various schemes, for example, replacing all “A”s with “K”s. Masking techniques may be reversible, dynamic, selective or incremental. In step 614 , the members or researchers saved the query result and in step 616 , they perform the analytics using the capabilities of the research bench or transport to suitable research tool. (Important to mention that the code used to mask is unknown to the user)
[0032] FIG. 7 depicts the emergency service in the social network. In step 702 , the members subscribe for emergency service. In step 704 , the members list down the contacts who must be contacted in case of emergency. Here, the members should write the name and contact information such as phone number, email of the person. In step 706 , the members are required to write messages to be sent in case of emergency to the specified contacts. In step 708 , the members pay the subscription fee.
[0033] In step 710 , the members invoke emergency service in case of emergency situation either on mobile or on computer. In the step 712 , the members send the alert message just by clicking the emergency button to mobile devices or email ids of the specified contacts along with location details. If the alert message is sent through mobile, at 714 , then the application resolves location details through the radio signals acknowledged by mobile tower and corresponding frequency. If alert message is sent through computer, at 716 , application resolves location details through Ip address of the device. In the step 718 , the location embedded alert message received by receiver's device.
Non-Transitory Computer-Readable Media
[0034] Any of the computer-readable media herein can be non-transitory (e.g., volatile or non-volatile memory, magnetic storage, optical storage, or the like).
Storing in Computer-Readable Media
[0035] Any of the storing actions described herein can be implemented by storing in one or more computer-readable media (e.g., computer-readable storage media or other tangible media).
[0036] Any of the things described as stored can be stored in one or more computer-readable media (e.g., computer-readable storage media or other tangible media).
Methods in Computer-Readable Media
[0037] Any of the methods described herein can be implemented by computer-executable instructions in (e.g., encoded on) one or more computer-readable media (e.g., computer-readable storage media or other tangible media). Such instructions can cause a computer to perform the method. The technologies described herein can be implemented in a variety of programming languages.
Methods in Computer-Readable Storage Devices
[0038] Any of the methods described herein can be implemented by computer-executable instructions stored in one or more computer-readable storage devices (e.g., memory, magnetic storage, optical storage, or the like). Such instructions can cause a computer to perform the method.
[0039] While the various embodiments of the invention have been illustrated and described, it will be clear that the invention is not limited only to these embodiments. Numerous modifications, changes, variations, substitutions, and equivalents will be apparent to those skilled in the art, without departing from the spirit and scope of the invention. | This disclosure describes a system and methodology for sharing, analyzing and consolidating medical data on social networks in a well secured manner. It allows patients, medical professionals, and caregivers participate in an open media without the fear of their personal information being compromised. At the same time, it allows each user to benefit from analysis of clinical information available on network. It facilitates sharing of information with chosen contacts in a specific manner such that the visibility of information can be configured on individual basis. More importantly, it facilitates the creation of authentic source of medical database at the backend that can be made available for research and analytics on preserving privacy. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This patent application is a divisional of U.S. patent application Ser. No. 12/040,867, filed Feb. 29, 2008, issued as U.S. Pat. No. 8,236,008 on Aug. 7, 2012, which is incorporated by reference along with all other references cited in this application.
BACKGROUND OF THE INVENTION
The invention relates to the field of devices to treat human skin and more specifically to an abrasive tip used to exfoliate skin and tissue through the use of abrasive materials, where this tip delivers fluid to the skin and vacuums the fluid and abraded tissue during treatment.
As people age, they look for ways to maintain a youthful appearance. Some invasive cosmetic techniques include surgical approaches including eye lifts, face lifts, skin grafts, and breast lifts. However, these invasive techniques also have risks and potential complications. Some people have died during cosmetic surgery operations. Therefore, it is desirable to have noninvasive cosmetic techniques.
A noninvasive technique for obtaining a more youthful appearance is through microdermabrasion. Microdermabrasion is a process for removing dead cells from the outermost layer of the skin (the epidermis) to provide a younger and healthier looking appearance, remove wrinkles, clean out blocked pores, remove some types of undesirable skin conditions that can develop, and enhance skin tone.
The process of microdermabrasion must be performed with a certain degree of accuracy, so that underlying live layers of skin tissue are not removed or damaged, but that enough dead cells are removed to give effective results. Therefore, there is a need for improved system, devices, tips, and techniques for performing microdermabrasion.
BRIEF SUMMARY OF THE INVENTION
An abrasive tip is used to exfoliate skin and tissue through abrasive materials integrated in the tip. The tip also delivers fluid to the skin and vacuums the fluid and abraded tissue during treatment. In an implementation, the tip is replaceable and disposable.
The invention reduces the time period required for a microdermabrasion treatment. The invention simultaneously treats the skin with fluids, exfoliates the skin, and vacuums away the spent fluids, abraded skin particles, and other debris.
A wide variety of abrasive tips may be used with the invention. This may include, for example, different types of abrasive elements such as bristles, meshes, abrasive particles, or combinations of these. Many different sizes of tips are available. Thus, small skin surfaces such as the cheek, forehead, chin, and nose may be treated. Large surfaces such as the back, legs, or torso may also be treated.
In one embodiment, the fluids are directed to the perimeter of the abrasive tips. Thus, the skin to be exfoliated is surrounded with fluids. The skin is provided with a treatment of fluids before the microdermabrasion beings and a treatment of fluids after the microdermabrasion ends.
In an implementation, the invention is a device including: a tip having an abrading surface formed on a first side; a collar portion on a second side of the tip; a number of fluid channels formed on a second side of the tip, each channel extending through the collar through a first edge to a second edge of the tip, where the second edge of the tip is perpendicular to and touches the first side, and an angle between the first side and the first edge is less than ninety degrees; and at least one key notch, formed on the collar portion between two channel openings, where a surface of the collar is perpendicular to the first side. The fluid channels can conduct any fluid, including liquids or gases.
Further, in various specific implementations, the first side of the tip may have a circular shape. Each fluid channel is a groove formed in the first edge. There is a split in the collar portion at each point where a fluid channel passes through the collar. The fluid channels are evenly distributed about the second edge. An angle between the fluid channels is given by 360 degrees divided a total number of fluid channels (e.g., for four channels, the angle is 90 degrees; for three channels, the angle is 60 degrees; and for five channels, the angle is 72 degrees).
A first fluid channel has a first end at the first edge, a second fluid channel has a second end at the first edge, and the first and second ends are opposite of each other on the first edge. Then the ends of the fluids channels will be a maximum distance away from each other, while being on the first edge.
In a various specific implementations, the tip has four fluid channels. The abrading surface includes an abrasive disk connected to the first side (e.g., the abrasive disk can be abrasive paper like sandpaper glued to the abrading surface of the first side). The abrading surface includes of bristles connected to the first side. The abrading surface includes an abrasive mesh pad connected to the first side (e.g., the abrasive pad may be an exfoliating pad or sponge and made from a material such as nylon or natural fibers such as a loofah). The collar includes at least one key notch for each channel (e.g., for four channels, there are four key notches).
In an implementation, the invention is a device including: a tip having a number of bristles connected to a front surface on a first side; a fluid opening, surrounded by the bristles, on the first side, where the fluid opening extends to a second side, opposite to the first side; a first cylindrical side surface, connected to and perpendicular to the first side; and a number of prongs which extend away from the first cylindrical side surface and toward second side (e.g., the prongs may extend in a splay-like fashion from the tip).
Further, in various specific implementations, the tip includes a cylindrical column on the first side extending from the front surface away from the second side, where the fluid opening extends through the cylindrical column. The length of the cylindrical column is less than a length of the bristles. The cylindrical column may be about 50 percent (e.g., 40 to 60 percent) of a length of the bristles.
An implementation of the tip has at least three prongs. An implementation of the tip has at least four prongs. An angle between the prongs is given by 360 degrees divided a total number of prongs (e.g., for four prongs, the angle is 90 degrees; for three prongs, the angle is 60 degrees; and for five prongs, the angle is 72 degrees). Further, in an implantation, a first prong extends from a first position on the first cylindrical side surface, a second prong extends from a second position on the first cylindrical side surface, and the first and second positions are opposite of each other (i.e., 180 degrees apart) on the first cylindrical side surface.
In various specific implementations, the prongs touch the front surface. When the prongs touch the front surface, there are three prongs. The bristles may be arranged in any number of groupings (e.g., an even number of groupings, an odd number of groupings, four groupings, five groupings, and six groupings).
In an embodiment, there is a second cylindrical side surface, concentric with the first cylindrical side surface and having a smaller circular cross-sectional area. This second cylindrical side surface is connected to the first cylindrical side surface through a step-down ring. When the tip has a second cylindrical side surface, there are four prongs. When there are four prongs, there are six groupings of bristles.
Other objects, features, and advantages of the present invention will become apparent upon consideration of the following detailed description and the accompanying drawings, in which like reference designations represent like features throughout the figures.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a microdermabrasion system according to the present invention.
FIG. 2 shows a wand of the present invention.
FIG. 3 shows a cross-sectional view of the wand with a tip holder, bristled tip, and handle.
FIG. 4 shows cross-sectional view of the wand and a vacuum loop flow path.
FIG. 5 shows a perspective view of the wand and the vacuum loop flow path.
FIG. 6 shows a perspective view of a first implementation of the bristled tip placed on the handle.
FIG. 7 shows a side view of the first implementation of the bristled tip placed on the handle and illustrates several dimensions.
FIG. 8 shows a front view of the first implementation of the bristled tip with three groups of bristles.
FIG. 9 shows a perspective view of a second implementation of the bristled tip with six groups of bristles in the tip holder.
FIG. 10 shows a side view of a second implementation of the bristled tip in the tip holder.
FIG. 11 shows a line diagram representation of the invention in use with the bristled tip.
FIG. 12 shows a perspective view of a third implementation of the bristled tip with six groups of bristles in the tip holder.
FIG. 13 shows a perspective view of a first implementation of an abrasive tip, tip holder, openings for fluid, and an annular space in which a vacuum removes fluid, skin particles, and other debris.
FIG. 14 shows a perspective view of a vacuum loop flow path for the abrasive tip and tip holder.
FIG. 15 shows a perspective view of the assembly of the first implementation of the abrasive tip and tip holder.
FIG. 16 shows a perspective view of a second implementation of a tip holder which includes channels to direct fluid, notches that accept keys on the abrasive tip, and the annular space.
FIG. 17 shows a perspective view of the back side of an abrasive tip which includes channels to direct fluid, a key that fits into notches in the tip holder, and collars which support the abrasive tip.
FIG. 18 shows a cross-sectional view of the abrasive tip and tip holder.
FIG. 19 shows a front view of the abrasive tip, tip holder, and the annular space around the abrasive tip.
FIG. 20A shows a front view of a first implementation of an abrasive tip having a six millimeter diameter and tip holder.
FIG. 20B shows a front view of a second implementation of an abrasive tip having a nine millimeter diameter and tip holder.
FIG. 21 shows a side view of a third implementation of an abrasive tip with an abrasive mesh having a six millimeter diameter.
FIG. 22 shows a side view of a fourth implementation of an abrasive tip with an abrasive mesh having a nine millimeter diameter.
FIG. 23 shows options for packaging the abrasive tips, abrasive mesh tips, bristled tips, and bottles of fluid.
DETAILED DESCRIPTION OF THE INVENTION
This patent application incorporates by reference U.S. patent application Ser. No. 10/393,682, filed Mar. 19, 2003; U.S. Pat. No. 6,695,853, filed Nov. 21, 2001, and issued Feb. 24, 2004; and U.S. provisional patent application Ser. No. 10/393,682, filed Mar. 19, 2003.
FIG. 1 shows an example of a microdermabrasion or dermabrasion system 30 according to the present invention, which incorporates a wand 10 . A vacuum opening 18 b is connected with a vacuum source 40 as described above, by a vacuum line 42 . A collection reservoir 51 and, optionally, an inline filter 60 are connected in the vacuum line 42 between wand 10 and vacuum source 40 . Vacuum line 42 connects to an input 52 to a collection reservoir 50 via an elbow 54 , for example, and an output 56 connects with a second vacuum line 44 via an elbow 58 , for example. A manifold cover 59 seals the input ( 52 , 54 ) and output ( 56 , 58 ) connections with the collection reservoir 51 which is typically a jar made of glass or plastic for example. An extension tube 53 connects with input 52 , 54 and extends into the collection reservoir 51 to ensure effective delivery of waste materials (abraded skin particles and, optionally, fluids) to collection reservoir 51 .
Optionally, a back-up filter 60 may be provided in-line between the vacuum line 44 and a vacuum line 46 as added insurance that no or substantially no fluid, skin particles, abrasive particle or other materials being collected by collection reservoir 51 can be transported to vacuum source 40 . Filter 60 may be an in-line condensation filter, such as water condenser produced by Wilkerson Labs and available as part no. F0001-000 from Nor-Cal Controls, Incorporated of San Jose, Calif.
The vacuum source 40 may be the same as that provided for currently existing microdermabrasion devices, such as the ProPeel, MDPeel or iPeel, for example, each available from Emed, Incorporated of Westlake Village, Calif. A power switch is used to activate the vacuum source 40 and a vacuum in the range of about 2 pounds per square inch to about 14 pounds per square inch is generally used during a procedure, depending upon the skin condition of the person being treated.
Tube 14 extends from the microdermabrasion wand 10 , and connects with an output 72 of a fluid reservoir 71 via an elbow 74 , for example. A breather line 76 may be connected inline via a T-joint 76 ′, for example, or other interconnection, and includes an adjustable valve 78 or other means for varying an amount of air that is allowed into the tube 14 . This feature not only allows the amount of vacuum to be adjusted for a given fluid, but allows fluids having different viscosities to be applied at the same vacuum level, since different viscosities will require varying amounts of air to be introduced into the breather line 76 , to give a constant vacuum level.
Alternatively, a breather line or input with adjustment valve may be located on elbow 74 or directly on a manifold cover 79 . Still further, a valve or other flow control mechanism may be provided in the fluid delivery line 14 to control the amount of liquid passing through the line. This feature can be provided alternatively, or in addition to the breather line discussed above.
An input may be provided in manifold cover 79 which may be open to the atmosphere to prevent vacuum buildup in fluid reservoir 71 . Manifold cover 79 seals the output ( 72 , 74 ) connections with fluid reservoir 71 which is typically a jar made of glass or plastic, for example, and contains lotions, vitamins, other skin treatment fluids, or combinations of these to be applied to the skin by wand 10 . An extension tube 73 connects with output 72 , 74 and extends into the fluid reservoir 71 to near the bottom of the fluid reservoir to ensure that most all of the contents of fluid reservoir 71 are capable of being delivered through the system.
Abrasive particles, such as corundum crystals, sodium bicarbonate particles or other abrasive particles, including those discussed in U.S. Pat. No. 5,971,999 (which is incorporated by reference), for example may be included in fluid reservoir 71 for delivery through the system to perform a microdermabrading function. However, in the present invention, microdermabrasion is typically accomplished via a bristled tip 105 , abrasive tip, or both. If used, the abrasive particles may be used together with any of the fluids mentioned above, with some other fluid carrier medium, such as those described in U.S. Pat. No. 5,971,999, for example, or both.
Fluid reservoir 71 may contain solution or a suspension for purposes other than abrasion or pure abrasiveness. The compositions used in the present invention can include a wide and diverse range of components. The International Cosmetic Ingredient Dictionary and Handbook, 12 th edition, 2008, which is incorporated by reference, describes an extensive variety of cosmetic and pharmaceutical ingredients commonly used in the skin care industry, which are suitable for use in the compositions of the present invention.
General examples, types or categories, or both, of compounds that may be employed include: beaching formulations (e.g., 2 percent to 4 percent hydroquinone, 2 percent Kojic Acid, 1 percent Vitamin K, and 1 percent Hydrocortisone in an aqueous base); acne treatment formulations (e.g., Salycilic Acid, alcohol base buffered by witch hazel, etc.); fine lines/wrinkle treatment formulations (e.g., Hyaluronic acid is an aqueous base); hydrating formulations (e.g., Calendula, vitamins A, D, E, or other vitamins, or combinations of these in a mineral oil base); antioxidant formulations; free radical scavengers (e.g., vitamins A, E, K, or other vitamins, or combinations of these in a mineral oil base); pH adjusters; sunscreen agents; tanning agents and accelerators; nonsteroidal anti-inflammatory actives (NSAIDS); antimicrobial and antifungal agents; moisturizers; lightening agents; humectants; numbing agents; and water, or combinations of these.
The solution or suspension may contain extracts such as those from plants, vegetables, trees, herbs, flowers, nuts, fruits, animals, or other organisms, or combinations of these. Such extracts may be used to help condition the skin, provide a relaxing aroma, or both.
The solution or suspension may also contain viscosity increasing or decreasing agents, colorants, or combinations of these. In a specific implementation of the invention, the viscosity of the fluids used is about 1 centipoise (e.g., about 0.5 to 1.5 centipoise). However, in other implementations, the viscosity may range from 1 centipoise to 100 centipoise. The viscosity may be, for example, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 10, 20, 30, 40, 50, 60, 70, 80, 90, or more than 100 centipoise. In other applications the viscosity may be less than 1 centipoise.
In a specific implementation, the fluids, abrasive particles, or both for fluid reservoir 71 may be packaged as a concentrated solution, powder, solids, or combinations of these to be mixed, diluted, or both by the microdermabrasion system 30 .
Other examples of product categories that may be employed alone or in combination with other compounds include, antiseptics, astringents, cleansers, pore decongestants, balms, botanicals, collagen stimulators, herbs, microemulsifiers, oxygen delivery vehicles, proteins, serums, skin firming agents, toners, topical anesthetics, emulsions, ointments, gels, tyrosinase inhibitors, and other related product categories.
Individually named products that may be used (with associated benefit indicated parenthetically) include: Aloe Vera (calming); alpha hydroxy acids (peel); alphalipoic acid (antioxidant); benzoil and other peroxides (acne); ceramide (hydrator); copper (toning); copper peptide (toning); CoQ-10 (coenzyme Q-10) and other enzymes (toning); cortisone (calming); glycolic acids (peel); hyaluronic acid (collagen stimulation); hydrolipids (hydrator); hydroquinones (bleaching); lactic acids (peel); magnesium ascorbic phosphate (free radical scavenger, collagen stimulator, bleaching); niacin (vascular dilation); phospholipids (moisturization); potassium (toning, psoriasis), and salycilic acids (acne); and related products. Of course, any combination of such elements may be provided—even in connection with abrasive particles.
Any of the products listed may be used with the microdermabrasion treatment tips of the invention. For example, the groves of a tip which may be used to conduct botanicals, Aloe Vera, or alpha hydroxy, to name a few examples, to a patient's skin. The channels through which fluid is delivered may be partially formed in a tip and partially formed in a tip holder. When the tip and tip holder are put together, the groves in each of these mate to form a complete channel opening.
As another example, coenzyme Q-10, glycolic acids, or vitamin E, to name a few example, may be conducted through an opening, surrounded by bristles, to the skin of a patient. The opening may extend to a position closer to patient's skin through a cylindrical column, nipple, or other structure to achieve a similar purpose.
Note, however, the present system may be used by eliminating the fluid reservoir 71 altogether, where microdermabrasion is performed in a “dry state” and tube 14 is simply left open to atmosphere, with or without a filter or valve, or both, for adjusting the amount or flow rate of air that is allowed into tube 14 . Similarly, dry or externally lubricated vacuum massage of tissue may be accomplished by a tip having a smooth surface.
FIG. 2 shows a wand 10 in a specific implementation of the present invention. To perform microdermabrasion, a user holds the wand in the user's hand and applies the tip to a patient. The wand has an elongated handle 205 which facilitate grasping by a user. The wand 10 includes a tip holder 200 which, in a specific implementation, holds a bristled tip 105 . In other implementations, other types of tips may be used including, for example, tips with abrasive particles, abrasive disks, and tips with smooth surfaces.
Tube 14 is connected to an end of the wand 10 . Tube 14 delivers the fluids to the wand 10 . The fluids flow through the wand 10 . The fluids exit the bristled tip 105 , the tip holder 200 , contact the skin, and the flow back into wand 10 and through vacuum line 42 which connects to a port 18 b.
There are numerous technique on how a user can apply the wand and tip to perform microdermabrasion. For example, one approach is draw the tip across the skin of the patient in a single direction, generally away from the center or nose of the patient's face (when working on the patient's face). Another approach is to use a scrubbing motion, moving the tip back and forth on the face.
One of ordinary skill in the art will appreciate that many different shapes and materials may be employed for the handle 205 and the present invention is not to be limited to an elongated, substantially cylindrical handle 205 as shown. In the example of FIG. 2 , handle 205 is made of plastic, such as nylon or other plastic having sufficient toughness and mechanical strength, but may also be made of metal, such as stainless steel or aluminum, for example, or ceramics or composites such as carbon fiber. The handle may include a combination of materials. For example, a rubber sleeve may be placed over handle 205 which may be made of plastic. The rubber sleeve provides a secure surface for a user to grasp. The surface of the handle may also be textured, knurled, or both in order to provide a slip-resistant surface.
Tube 14 may be flexible and may be made of polyvinyl chloride (PVC) or other compatible plastic or polymer, for example. Similarly, all other vacuum lines (e.g., vacuum line 42 ) described herein are flexible to afford maneuverability to wand 10 and may be made of PVC or other compatible plastic.
FIG. 3 shows an exploded view of wand 10 . A user may assemble or disassemble the wand by placing abrasive tip 105 onto the front of the wand 10 followed by tip holder 200 . In an implementation, the user can easily replace parts of the wand as needed. Because the wand's design incorporates replaceable and easy to remove and assemble parts, users are able to do their own maintenance and repair.
Handle 205 is annular or tubular, providing a passageway 305 for fluids in tube 14 to pass through. Fluid flows through passage way 305 , bristled tip 105 , and tip holder 200 where the fluids contact the skin. The fluids then flow back into the wand 10 and through vacuum line 42 .
FIG. 4 shows a cross-sectional view of wand 10 . A vacuum loop 410 shows the flow of fluids. For use in microdermabrasion, wand 10 is positioned such that tip holder 200 contacts the skin surface to be microabraded. Vacuum source 40 (see FIG. 1 ) is turned on to establish a vacuum within the system. The order of positioning and turning on the vacuum source 40 is not critical as the vacuum source 40 can be turned on prior to contacting the tip holder 200 to the skin. The vacuum loop 410 will not be closed until such time that an opening 445 on the tip holder 200 is sealed by the skin.
With reference to FIG. 1 and FIG. 4 , when vacuum source 40 is turned on a targeted area of the skin is drawn up into opening 445 and a central portion of the targeted area of skin is drawn into contact with bristled tip 105 . At the same time, fluids in fluid reservoir 71 are drawn through tube 14 and into wand 10 . The fluids follow vacuum loop 410 through passageway 305 , through bristled tip 105 , through an opening 435 on the bristled tip 105 and finally out opening 445 where the fluids treat the skin.
The fluids then reenter opening 445 and pass through a vacuum created in an annular space 440 . Vacuum loop 410 now carries with it the exfoliated skin particles and any other waste that was removed through the microdermabrasion process. The fluids travel within vacuum line 42 and are collected in the collection reservoir 51 . Since annulus 440 surrounds both the bristled tip 105 and opening 435 , there is little to no spent fluid or debris that must later be cleaned from the skin.
This application describes a specific implementation of the invention, where the flow direction is as shown in FIG. 4 : the fluid is delivered through a passageway in the wand to the tip. This fluid may then vacuumed into the vacuum line. However, an alternate embodiment of the invention, the flow direction is opposite of that shown in FIG. 4 , where fluid is drawn into the central passageway of the wand from line 42 .
As the user of the wand 10 glides the tip holder 200 over the skin, bristled tip 105 is scraped over the skin wherein microdermabrasion of that portion of the skin is performed.
A male to female connection between the bristled tip 105 and the handle 205 acts as a helpful guide to properly position the bristled tip to the handle. Bristled tip 105 includes a cavity 446 . In a specific implementation, cavity 446 forms a female core which fits onto a distal end 305 of a cannula 300 . That is distal end 305 forms a male core which fits into cavity 446 . Bristled tip 105 fits onto distal end 305 using, for example, an interference or press fit. However, in other implementations, other attachment mechanisms may be used. For example, bristled tip 105 may include a tab to create a snap fit between the bristled tip 105 and the cannula 300 . As another example, bristled tip 105 may thread onto cannula 300 .
In other implementations, distal end 305 may form a female core. Bristled tip 105 may then include a male protrusion that fits into the female core of distal end 305 .
Bristled tip 105 also includes a cavity 447 . Cavity 447 is coupled to the opening 435 at one end of the bristled tip 105 and cavity 446 at the opposite end of bristled tip 105 . This allows fluids to pass through bristled tip 105 using cavity 446 , cavity 447 , and eventually exiting at opening 435 .
Tip holder 200 fits over bristled tip 105 and onto vacuum head base 18 . One or more O-rings 18 a or other sealing members (e.g., gasket) may be provided between vacuum head base 18 and tip holder 200 to facilitate the pressure tight seal. Tip holder 200 may be friction fit, provided with threads, or both, or another attachment means may provide a pressure tight fit between the components. For example, a snap fit such as an annular snap fit may be used. Alternatively, the tip holder 200 may be integrally machined or molded with vacuum head base 18 . In another implementation, bristled tip 105 may be integrally machined or molded with tip holder 200 .
FIG. 5 shows a perspective view of the vacuum loop 410 . When vacuum source 40 (see FIG. 1 ) is turned on, fluids are pulled through handle 205 and cannula 300 . The fluids continue through distal end 305 of the cannula where the fluids pass through bristled tip 105 and exit at an opening 435 on the bristled tip 105 . The fluids exit tip holder 200 at an opening 445 and treat the skin. A vacuum created in annular space 440 pulls the fluids back into the tip holder 200 where the fluids move past the outside of bristled tip 105 . The fluids are pulled into vacuum line 42 and are collected in collection reservoir 51 (see FIG. 1 ).
FIG. 6 shows a perspective of bristled tip 105 placed onto cannula 300 . In a specific implementation, the bristled tip 105 includes support ribs 600 a , 600 b , and 600 c . When tip holder 200 is fitted over the bristled tip, the support ribs connect with the inner surface of the tip holder. The support ribs help to support and stabilize the bristled tip 105 in tip holder 200 . The support ribs help to ensure that the bristled tip 105 is properly aligned in the holder. Fluid can flow through the tip, treat the skin, and be vacuumed back into the tip holder.
In a specific implementation, support ribs 600 a , 600 b , 600 c are attached such that they are initially flush with a front face 605 of the bristled tip 105 . However, in other implementations, the support ribs may be attached such that they are offset from the front face 605 of the bristled tip 105 (see, e.g., FIG. 9 ). Support ribs 600 a , 600 b , 600 c extend outwardly and then turn to extend longitudinally down the length of the bristled tip 105 and at an angle such that their tips 606 a , 606 b , and 606 c are splayed. The angle may match the interior surface angle of the tip holder 200 . This allows support ribs 600 a , 600 b , 600 c to contact the inner surface of the tip holder 200 for support and stabilization.
When the tip and tip holder are assembled together, support ribs 600 a , 600 b , and 600 c touch an inside surface of the tip holder and help form annular space 440 . Specifically, the annular space is formed between the inner surface of the tip holder and exterior surface of bristled tip 105 . Generally, the less volume or space taken up by the ribs enlarges the volume of the annular space.
In a specific implementation, fluids and abraded tissues are vacuumed back into the wand through the annular space. This annular space creates an annular vacuum region that surrounds the passageway of the wand where fluids flow to the tip. The volume of the annular space may vary depending on the specific design, but generally, larger volume annular spaces will help prevent potential blockage or other similar problems, especially when compared to pores or other structures that will restrict flow more.
The support ribs also help to ensure that the bristled tip 105 is properly aligned so that fluid can flow through, treat the skin, and be pulled back into the tip holder.
In a specific implementation, support ribs 600 a , 600 b , 600 c are positioned at equal distances from each other around the bristled tip 105 . For example, the support ribs may be placed at 60 degree angles from each other as shown. However, in other cases, the support ribs may not be equally positioned in relation to each other. It should be appreciated that any arrangement or number of support ribs (including no support ribs) is possible so long as the fluids are able to pass from the front of the tip holder 200 to the back of the tip holder 200 .
Consequently, a flange, or a portion of a flange may be used between the bristled tip 105 and the tip holder 200 either with or without one or more support ribs. For example, where a flange completely encircles the bristled tip 105 , the flange may contain one or more openings which allow fluids to pass from the front of the tip holder 200 to the back of the tip holder 200 .
In a specific implementation, there may be a total of three support ribs as shown in FIG. 6 . However, in other implementations there may, for example, be four support ribs. In yet another implementation, there may be no support ribs, one, two, five, or more than five support ribs.
In a specific implementation, tips 606 a , 606 b , and 606 c of the support ribs may have beveled edges. These beveled edges allow the tip holder 200 to easily slide on and off over the bristled tip 105 .
In a specific implementation, the support ribs 600 a , 600 b , 600 c are molded or machined as an integral part of the bristled tip 105 as shown. In other implementations, the support ribs are molded or machined as an integral part of the tip holder 200 . For example, the interior surface of tip holder 200 may contain one or more protruding support ribs that contact bristled tip 105 when tip holder 200 if placed over bristled tip 105 . In yet another implementation, there may be a combination of support ribs which may be molded or machined as an integral part of the tip holder 200 and bristled tip 105 .
The tip holder 200 is smooth surfaced and adapted to glide over the skin as fluids (e.g., lotions, conditioners, vitamins, oils) exit the wand 10 to treat the skin. Tip holder 200 and treatment head 105 may, for example, be impregnated with polytetrafluoroethylene (PTFE), treated with wax, or include other hydrophobic ingredients to ensure that fluids do not adhere to tip holder 200 and treatment head 105 .
The tip holder 200 and treatment head 105 may be made of metal (e.g., stainless steel, aluminum, titanium, brass) or plastic such as nylon, thermoplastics, polyethylene, polycarbonate, acrylonitrile butadiene styrene (ABS), or Delrin. Glass, such as Pyrex, for example, may also be used. Tip holder 200 may be, although not necessarily, transparent or translucent. A transparent tip holder may allow better visualization by the operator during use.
The treatment tip and tip holder of the invention (in the various embodiments described and shown in this application) are designed to be removable and installable by the user. Further, the user can dispose of used or old tips or holders, or both, and easily replace them with new (or clean) ones. Also, the user can remove the tips to clean them or clean the passages to ensure the flow, vacuum and fluid, are clear, so that the microdermabrasion device will be operating at full efficiency. Also, in an embodiment, the tip and tip holder are designed to be low cost (e.g., made of less expensive materials) and disposable.
The design may be such that the tip wears faster than the tip holder. So users may stock up with greater numbers of replacement tips than holders. When a tip wears out, the user replaces the tip without needing to replace the holder. This is analogous to the situation of replacing an ink refill insert of a pen. For example, the holder may be replaced once for every seven (or other number) of tips. This lowers the cost of use for users, because the tip, which needs more frequent replacement because it is subject to more wear and tear, is replaceable separately from the tip holder.
FIG. 7 is a side view of bristled tip 105 . Table A below shows several implementations for the various dimensions of bristled tip 105 . It should be appreciated, however, that many other dimensions are possible.
TABLE A
First Implementation
Second Implementation
Dimension
(values in mm)
(values in mm)
A
7-13
10
B
2-4
3
C
9-17
13
According to one aspect of the invention, the length of the bristle strands from the core to their free ends may, for example, range from about 1 millimeter to about 4 millimeters. This includes, for example, less than 1 millimeter, 2, 3, and more than 4 millimeters.
In a specific implementation, support ribs 600 a , 600 b , and 600 c (shown in FIG. 6 ) extend from the front face 605 of the bristled tip 105 to a back face 705 of the bristled tip 105 as shown in FIG. 7 . However, this is not always the case. In other implementations, the support ribs may terminate before reaching the back face 705 . For example, the support ribs may only extend 30 percent, 50 percent, or 75 percent of the dimension “a” of the bristled tip 105 . In yet another implementation, the support ribs may extend past back face 705 . Moreover, the distance that each support rib extends down the bristled tip 105 may not be the same. For example, support rib 600 a may extend for a distance that is 50 percent the length of dimension a, while support rib 600 b may extend for a distance that is 75 percent the length of dimension a.
FIG. 8 is a front view of the bristled tip 105 and tip holder 200 . In a specific implementation, the bristled tip 105 includes four groups of bristles 800 a , 800 b , 800 c , and 800 d . In another specific implementation there may be six groups of bristles. In other implementations, there may be just one group of bristles, two, three, five, seven, eight, nine, ten, eleven, twelve, or more than twelve groups of bristles.
The groups of bristles 800 a , 800 b , 800 c , and 800 d form a ring around an opening 435 through which fluid flows out. Bristles 800 a , 800 b , 800 c , and 800 d separate the opening 435 from the skin so that fluid can flow out of the opening. In a specific implementation, opening 435 is on the same plane as face 605 of the bristled tip 105 . In other implementations, opening 435 may be on a different plane. For example, opening 435 may be recessed into face 605 or opening 435 may protrude out from face 605 . In an implementation where opening 435 protrudes out, the fluids exit opening 435 closer to the skin. This helps to ensure that the skin is treated with fluids before the fluids are pulled back (or suctioned) into the tip holder 200 .
In a specific implementation, the surface area of opening 435 through which fluid flows out of may be about 0.5 square millimeters to about 4 square millimeters. This includes, for example, 0.6, 0.7, 0.8, 0.9, 1, 2, 3, or more than 4 square millimeters. In an implementation, the surface area of opening 453 may be less than 0.5 square millimeters.
In an implementation, the total surface area for the openings for fluid may occupy a range from about 1 percent to about 10 percent of the total surface area of the treatment head. This includes, for example, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5 percent, or more than 10 percent of the total surface area of the treatment head. In other implementations, the percentage may be less than 1 percent.
In the implementation shown in FIG. 8 , the groups of bristles 800 a , 800 b , 800 c , and 800 d are equally spaced from each other, and surround opening 435 . However, in other implementations, the groups of bristles may not be equally spaced from each other, may only occupy a certain region of the treatment head, or both. For example, in a specific implementation, bristles may only occupy the top half of the bristled tip 105 . In this specific implementation, the bristled tip 105 may be intended to travel in a specific direction over the skin. For example, if the skin is particularly sensitive then the direction of travel may be such that the leading edge, i.e., the edge that first contacts the skin, is the edge that does not include the bristles. This allows the fluids to contact the skin before the bristles to provide, for example, lubrication or numbing agents. The trailing edge, i.e., that edge that does include the bristles can then contact the patient's skin to provide the microdermabrasion.
In yet another implementation, opening 435 may be located at a different region of the bristled tip 105 , such as near an edge of the bristled tip. Furthermore, there may be more than one opening through which fluid flows out of. For example, there may be two, three, four, five, six, seven, or more than eight openings for fluid to flow out of. In a specific implementation, these openings may then surround the group or groups of bristles.
The bristles may be made from a synthetic material, natural material, or a combination of synthetic and natural materials. Synthetic materials include, for example, polyethylenes, polyamides, polymers, nylon, polybutylene terephthalate (PBT), polyvinylidene fluoride (PVDF), acetyl resins, polyesters, fluoropolymers, polyacrylates, polysulfones, thermoplastics, or combinations of these. Metal strands may also be used. Natural bristles may be made, for example, from the hair of a boar, cow, horse, mink, cashmere, buffalo, pony, goat, mongoose, oxen, squirrel, badger, weasel, or kolinsky weasel.
The bristles may contain polytetrafluoroethylene (PTFE), be treated with wax, or include other hydrophobic ingredients to ensure that fluids do not adhere to the bristles. The bristles may also contain kaolin, or other fillers or additives.
In a specific implementation, the individual strands making up the bristles may be crimped. Crimped strands may provide a softer brushing action and reduce breakage. In another implementation, the bristles may be straight. Straight bristles may provide a stiffer brushing action.
The bristles may have a stiffness grade of about 0.5 centinewtons per square millimeter to about 30 centinewtowns per square millimeter. For example, the stiffness grade may be 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, or 29 centinewtons. Depending on the application, the stiffness grade may be more than 30 centinewtons or less than 0.5 centinewtons.
In still another aspect, a bristled tip 105 may include a mixture of bristle groups and strands having differing lengths, materials, cross-sectional areas, characteristics, or combinations of these. For example, a specific implementation may include a directional bristled tip. The leading edge of bristles may have a higher stiffness grade, or be more abrasive, than the trailing edge of bristles. This allows, for example, the more abrasive bristles to contact the skin first and remove a first layer of skin cells. Since the second layer of skin cells may be more sensitive, the trailing edge of bristles may have a lower stiffness grade, or be less abrasive so as to not irritate the skin.
In a specific implementation, the bristle strands may have uniform cross-sectional areas. In other implementations, the cross-sectional areas may vary across bristle strands.
A group of bristles may form a diameter that ranges from about 0.5 millimeters to about 20 millimeters where a larger treatment head is used. This includes 0.6, 0.7, 0.8, 0.9, 1, 2, 3, 4, 5, 10, 15, or more than 20 millimeters. The diameter may also be less than 0.6 millimeters. Where a group of bristles do not define a circular cross-section, the term “diameter” may be used to refer to the diameter of a circle that circumscribes the largest cross section of the noncircular group of bristles.
The total surface area for a group or groups of bristles at their free end may range from about 8 square millimeters to about 320 square millimeters. This includes for example, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 25, 30, 40, 50, 100, 150, 200, 250, 300, or more than 320 square millimeters. The surface area may also be less than 8 square millimeters. The smaller surface areas may be more appropriate where the area for microdermabrasion is small such as a patient's face. The larger surface areas may be more appropriate where the area for microdermabrasion is large such as a patient's back, chest, arms, or legs.
In a specific implementation, a group of bristles may have a similar cross-sectional area throughout the length of the group of bristles. However, in other implementations, the cross-sectional area will vary. For example, in the case of a group of crimped bristles, the cross-sectional area at the free end of the bristles may be larger than the cross-sectional area of the bristles at their crimped end. This is because crimped bristles have a tendency to splay out at their free ends.
In an implementation, the total surface area for all the groups of bristles may occupy a range from about 17 percent to about 60 percent of the total surface area of the bristled tip. This includes, for example, 18, 19, 20, 21, 22, 23, 24, 25, 30, 35, 40, 45, 50, 55, or more than 60 percent. In other implementations, the percentage may be less than 17 percent.
In a specific implementation, each group of bristles has a reference point. The reference point may be the center of the group of bristles if, for example, the bristle strands are arranged to form circular shapes. Alternatively, the reference point may be defined as some other point, so long as the definition is consistent among the groups of bristles.
A group of bristles may be separated by a distance of about 0.5 millimeters to about 5 millimeters from their respective reference points. This includes, for example, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.5, 4, 4.5 or more than 5 millimeters. In other implementations, the distance will be less than 0.5 millimeters.
The bristles may be attached to the bristled tip 105 using, for example, stapling, fusion, gluing, or other attachment method, or combinations of these. In stapling, a group of bristles is folded over a staple and forced into a cavity in the tip. In fusion, the bristles are fused with heat and the resulting tuft is molded with the tip.
In a specific implementation, the bristles are distributed along a planar surface 605 of bristled tip 105 . However, in other implementations, the surface may not be planar. For example, the surface may be convex or concave. The bristles may also be distributed over a helical surface. These nonplanar surfaces may be used, for example, on skin surfaces that are not planar such as the edge of patient's jawline or the curved surface of a patient's forehead. Bristles distributed on a nonplanar surface may be better able to fully contact the patient's skin while maintaining the same level of pressure across all the bristles.
In another implementation, one or more groups of bristles may be attached to springs within the bristled tip 105 . These springs may then compress as the bristled tip 105 is moved over the nonplaner surfaces of a patient's skin. These springs allow the bristles to conform to nonplaner skin surfaces.
FIG. 9 shows an example of a specific implementation of a bristled tip 905 . In a specific implementation, bristled tip 905 may have six groups of bristles ( 910 a , 910 b , 910 c , 910 d , 910 e , 910 f ), four support ribs ( 915 a , 915 b , 915 c , 915 d ) which are offset from a face 920 of the bristled tip 905 , and an opening 930 which is at the end of a nipple 925 .
Nipple 925 extends some distance away from the face 920 of the bristled tip. The opening may extend from about 30 percent to about 75 percent the length of the bristles, including, for example, less than 30 percent, 50 percent, or more than 75 percent the length of the bristles. This nipple places opening 930 closer to the skin and helps to ensure that the fluid contacts the skin before being vacuumed, suctioned, or sucked back into tip holder 920 .
Support ribs 915 a , 915 b , 915 c , and 915 d may be offset from face 920 of the bristled tip and attached at any point along the length of the bristled tip 905 . The ribs or prongs of the tip generally conform to an inside surface of a tip holder into which this tip fits. In a specific implementation, the distance for the offset is the same for all support ribs 915 a , 915 b , 915 c , and 915 d . In other implementations, the support ribs may be offset at different distances. For example, support rib 915 a may be offset from face 920 by 0.5 millimeters, while support ribs 915 a , 915 b , and 915 c may be offset from face 920 by 1 millimeter.
Offsetting the support ribs allows, for example, an uninterrupted annular space 940 to be created near the front of the tip holder 920 . This allows fluids to more easily pass back into tip holder 920 without being blocked by any structures.
In a specific implementation, a tip holder 920 used to hold bristled tip 905 may be the same as tip holder 200 (see, e.g., FIG. 5 ) that is used to hold bristled tip 105 (see e.g., FIG. 5 ) which in a specific implementation has four groups of bristles. However, in other implementations, tip holder 920 may be different from tip holder 200 . For example, tip holder 920 may have a larger opening 935 to accommodate the additional bristle groups.
FIG. 10 shows a side view of tip holder 920 placed over bristled tip 905 and the resulting annular space 1005 . In a specific implementation, each length “b” of a bristle strand is the same and extends to an opening 1000 of the tip holder 920 as shown in FIG. 10 .
In other implementations, bristles 910 a , 910 b , 910 c , 910 d , 910 e , 910 f may extend past opening 1000 . The bristles may extend past opening 1000 by about 0.5, 1, 2, 3, 3.1, 3.2, 3.3, 3.4, 3.5, 4, 5, or more than millimeters. The bristles may also extend past the opening 1000 by a distance that is less than 0.5 millimeters.
In yet another implementation, the free ends of bristles 910 a , 910 b , 910 c , 910 d , 910 e , 910 f may terminate before reaching opening 1000 . The bristles may terminate from about 0.5, 1, 2, 3, 3.1, 3.2, 3.3, 3.4, 3.5, 4, 5, or more than 5 millimeters from opening 20 a . The bristles may also terminate at a distance less than 0.5 millimeters from opening 1000 .
For example, in FIG. 11 , the bristles 910 a , 910 b , 910 c , 910 d , 910 e terminate before reaching opening 1000 . This allows a skin 1105 to be pulled into opening 1000 to seal opening 1000 , which causes a closed loop to be formed. The skin then contacts the bristles. Simultaneously, fluid flows out of opening 930 , treats the patient's skin and is then removed through the vacuum in annular space 1005 . Since the vacuum in the annular space surrounds both the bristles 910 a , 910 b , 910 c , 910 d , 910 e and the opening 930 that the fluid exits from, there is very spent fluid or debris that needs to be later removed from the patient's skin.
In a specific implementation, the lengths of the bristles may vary. For example, the lengths of the bristles may vary such that the free ends of the bristles form a diagonal plane. This particular implementation allows wand 10 (see FIG. 1 ) to be held at the angle of the diagonal plane, which some users may find more comfortable, while still having all the bristles contact the skin.
As another example, the lengths of the bristles may also vary to form a concave or convex plane, or an angular or serrated profile, or another nonplanar surface, profile, or topography. These nonplanar implementations allow, for example, the bristled tip to follow the concave and convex contours of a patient's skin.
In a specific implementation, bristled tip 905 also includes a body 1006 with cross-sectional area of varying values. The front third section of bristled tip 905 tapers into a smaller cross-sectional area for the back two-thirds section.
FIG. 12 shows a specific implementation of a bristled tip 1205 . In a specific implementation, bristled tip 1205 may have six groups of bristles ( 1206 a , 1206 b , 1206 c , 1206 d , 1206 e , 1206 f ), three support ribs or prongs ( 1207 a , 1207 b , 1207 c ) which are attached flush with a face 1208 on the bristled tip 1205 , and an opening 1209 at the end of a nipple 1210 .
It should be appreciated that there may be many different combinations of bristled tips that include, for example, different numbers of bristle groups, support ribs and fluid openings, different attachment positions for support ribs, or different positions for fluid openings. For example, in a specific implementation, the bristled tip may include two support ribs and three groups of bristles. The support ribs may not be equally spaced from each other. For example, instead of being spaced at 0 degrees and 180 degrees, the support ribs may be spaced at 0 degrees and 92 degrees. Furthermore, a first support rib may be attached flush with the face of the bristled tip while a second support rib is offset 0.5 millimeters from the face of the bristled tip.
In a specific implementation, the tip may not be a bristled tip. Instead the tip may be a smoothed surface tip or a tip containing other abrasive elements.
In a specific implementation, bristled tip 1205 includes a body 1211 that has a constant cross sectional area.
FIG. 13 shows an example of an abrasive tip 1305 that does not have bristles. Abrasive tip 1305 is shown placed within a tip holder 1310 . Fluid flows out of openings 1315 a , 1315 b , 1315 c , and 1315 d . The fluids contact the skin and are then pulled back into a vacuum in an annular space 1320 . In a specific implementation, the openings are equally spaced from each other around the abrasive tip 1305 . Thus, fluids are able to completely and uniformly surround the target area of skin that is being treated. These fluids may, for example, help to dislodge debris on the skin to increase the effectiveness of the abrasive tip 1305 .
FIG. 14 shows a cross-sectional view of tip 1305 and tip holder 1310 . A vacuum loop 1405 shows the flow of fluids. Arrows on the vacuum loop 1405 indicate the direction of fluid travel. As described in earlier figures and with reference to FIG. 1 , vacuum source 40 pulls fluids from fluid reservoir 71 , through tube 14 and into wand 10 .
Tip holder 1310 as shown in FIG. 14 is connected to wand 10 . Fluids flow through a tube 1415 . The fluids then exit through one or more openings 1315 a (see FIG. 13 ), 1315 b , 1315 c , and 1315 d and then exit an opening 1420 on the tip holder 1310 . The fluids contact the skin and are then pulled back into opening 1420 by the vacuum in an annular space 1320 .
With reference to FIG. 1 , the fluids are then pulled into vacuum line 42 where they are collected in collection reservoir 51 .
FIG. 15 shows a specific implementation where the tip holder 1310 is a separate unit from the abrasive tip 1305 . In another implementation, tip holder 1310 and abrasive tip 1305 may be one unit. For example, tip holder 1310 and abrasive tip 1305 may be integrally molded or machined.
FIG. 16 shows the front of a specific implementation of a tip holder 1601 into which an abrasive tip 1602 is placed. Tube 1603 is surrounded by annular space 1604 . Support ribs 1615 a , 1615 b , 1615 c , and 1615 d support tube 1603 within tip holder 1610 .
Tip holder 1610 includes channels 1610 a , 1610 b , 1610 c , and 1610 d that are on a front surface 1620 of tube 1603 . The front surface 1620 is angled in towards the interior of tube 1603 . This then allows fluid that flows through tube 1603 to then be redirected along the channels.
In a specific implementation, the channels are equally spaced around the perimeter of tube 1603 . For example, in an implementation where tube 1603 has a circular cross section and four channels, the channels may located at 0, 90, 180, 270, and 360 degrees. In other implementations, there may be less than four channels (e.g., one, two, or three) or more than four channels (e.g, five, six, seven, or eight). Moreover, the channels may not necessarily be equally spaced from each other.
Tip holder 1610 may also include notches 1605 a , 1605 b , 1605 c , and 1605 d . There may be any number of notches. For example, there may be no notches, one, two, three, four, five, six, or more than 6 notches.
In a specific implementation, there may be a total of four support ribs ( 1615 a , 1615 b , 1615 c , 1615 d ) which support tube 1603 in annular space 1604 . Specifically, the annular space is formed between the inner surface of the tip holder and the exterior surface of tube 1603 . Generally, the less volume or space taken up by the ribs enlarges the volume of the annular space.
In a specific implementation, fluids and abraded tissues are vacuumed back into the wand through the annular space. This annular space creates an annular vacuum region that surrounds the passageway of the wand where fluids flow to the tip. The volume of the annular space may vary depending on the specific design, but generally, larger volume annular spaces will help prevent potential blockage or other similar problems, especially when compared to pores or other structures that will restrict flow more.
The four support ribs are equally spaced around the perimeter of tube 1603 . For example, the an angle between the support ribs is given by 360 degrees divided a total number of support ribs (e.g., for four support ribs, the angle is 90 degrees; for three support ribs, the angle is 60 degrees; and for five support ribs, the angle is 72 degrees). In other implementations, the support ribs may not be equally dispersed around the perimeter of tube 1603 .
While tube 1603 is shown with a circular cross-sectional area, this not always the case. For example tube 1603 may be a square tube, rectangular tube, triangular tube, elliptical tube, or any other hollow shape.
In the implementation shown in FIG. 16 , the ends of the support ribs are planar. However, in other implementations, the end of the support ribs may have an outwardly (e.g., convex) angular or beveled surface or edges. This allows fluid to more easily flow past.
In other implementations, there may be less than four support ribs. For example, there may be no support ribs, one, two, or three support ribs. In another implementation, there may be more than four support ribs, including for example, five, six, or more than seven support ribs.
It should be appreciated that any arrangement or number of support ribs (including no support ribs) is possible so long as fluids are able to pass through the vacuum created in annular space 1320 .
Consequently, a flange, or a portion of a flange may be used between the tube 1603 and the tip holder 1601 either with or without one or more support ribs. For example, where a flange completely encircles tube 1603 , the flange may contain one or more openings which allow fluids to pass from the front of tip holder 1601 to the back of tip holder 1601 .
In a specific implementation, the support ribs are molded or machined as an integral part of the tip holder 1601 .
In a specific implementation, tip holder 1601 is formed as a result of machining. However, in other implementations, tip holder 1601 may be formed using other manufacturing techniques such as casting, molding, injection molding, etching, or a combination of these including machining.
FIG. 17 shows the back of a specific implementation of an abrasive tip 1701 . In a specific implementation, the abrasive tip 1701 includes channels 1705 a , 1705 b , 1705 c , and 1705 d . Channels 1705 c and 1705 d are not shown due to the perspective view of the drawing. Abrasive tip 1701 also includes collars 1710 a , 1710 b , 1710 c , and 1710 d and a key 265 a.
In a specific implementation, the channels 1705 a , 1705 b , 1705 c , and 1705 d are equally spaced around the perimeter of the abrasive tip 1701 . For example, in an implementation where the abrasive tip 1701 has a circular cross-section and four channels, the channels may be located at 0, 90, 180, 270, and 360 degrees. In other implementations, the abrasive tip 1701 may include less than four channels, such as no channels, one channel, two channels, or three channels. In another implementation, there may be more than four channels, including, for example, five, six, seven, or more than eight channels.
Channels 1705 a , 1705 b , 1705 c , and 1705 d in the abrasive tip 1701 align with the channels 1610 a , 1610 b , 1610 c , and 1610 d in the tip holder 1601 as shown in FIG. 16 . When these channels are aligned they form the openings 1315 a , 1315 b , 1315 c , and 1315 d as shown in FIG. 13 that fluid flows out of. For example, with reference to FIGS. 13, 16, and 17 , channel 1705 a in the abrasive tip 1701 may align with channel 1610 a in the tip holder 1601 to form opening 1315 a . Channel 1705 b in the abrasive tip 1701 may align with channel 1610 b in the tip holder 1601 to form opening 1315 b . Channel 1705 c in the abrasive tip 1701 may align with channel 1610 c in the tip holder 1601 to form opening 1315 c . Channel 1705 d in the abrasive tip 1701 may align with channel 1610 d in the tip holder 1601 to form opening 1315 d.
The FIGS. 16 and 17 show U-shaped or semicircular shaped channels or grooves which, when aligned, form circular shaped openings. However, this is not always the case. In other implementations, the openings formed may have the shape of a polygon such as a rectangle or square, or the shape may be elliptical or oval. Furthermore, there may be a combination of differently shaped openings which are formed using differently shaped channels.
The U-shaped or other shaped grooves in the tip combine (or mate) with similar grooves in the tip holder to form a complete channel, through which the fluid will flow. Because of the design of the invention, when the tip and tip holder are separated, the grooves are exposed so that they can more easily be examined and cleaned. This will allow a user to more easily clean or clear the fluid channels in the tip, thus helping prevent clogging of the fluid channels (e.g., after use, the fluid has residue that after the fluid evaporates can clog a tip).
In a specific implementation, the openings allow fluid to flow out around the perimeter of the abrasive tip 1701 as opposed to the front surface of the abrasive tip 1701 . This prevents the tissue that is being treated from occluding the openings.
However, in other implementations, there may be openings on the surface of the abrasive tip 1701 itself. For example, there may be an opening for fluid located in the center of the abrasive tip 1701 . Additionally, there may also be a combination of openings at different locations. For example, there may be openings located at or near the perimeter of the abrasive tip 1701 and an opening or openings on the surface of the abrasive tip 1701 .
In a specific implementation, the openings all have the same cross-sectional areas. The cross-sectional areas may range, for example, from about 0.05 square millimeters to about 20 square millimeters. For example, the cross-sectional areas may be 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, 3.1, 3.2, 3.5, 4, 4.5, 5, 10, 15, or 19.9 square millimeters. Depending on the application, the cross-sectional area may be less than 0.5 square millimeters, or greater than 20 square millimeters. In other implementations, the cross-sectional areas of the openings will be different. For example, one opening may have a cross-sectional area of 0.3 square millimeters, while another opening may have a cross-sectional area of 0.5 square millimeters.
In yet another implementation, the cross-sectional area of a particular opening may vary from one end of the opening to the opposite end. This allows, for example, varying the flow rate and velocity of fluid exiting from the openings.
In a specific implementation key 265 a in the abrasive tip 1701 fits into any of notches 1605 a , 1605 b , 1605 c , and 1605 d in tip holder 1310 as shown in FIG. 16 . Thus, this specific implementation provides for four different positions for abrasive tip 1701 to be positioned in tip holder 1310 .
There may be any number of keys. For example, there may be no keys, one, two, three, four, five, or more than five keys. In a specific implementation, the number of keys on the abrasive tip 1701 will be the same as the number of notches on the tip holder 1601 . In another implementation, the number will be different. For example, there may be fewer keys on the abrasive tip 1701 than notches on the tip holder 1601 .
In a specific implementation, the sizes of the keys and notches are the same. In another implementation, the sizes may be different. In yet another implementation, the notches may be on the abrasive tip 1701 while the keys are on the tip holder 1601 , or there may be a combination arrangement. That is, an implementation may have a combination of keys and notches on both the abrasive tip 1601 and tip holder 1701 .
The key or keys ensure that the channels 1610 a , 1610 b , 1610 c , and 1610 d in the tip holder 1601 and channels 1705 a , 1705 b , 1705 c , and 1705 d in the abrasive tip 1701 are properly aligned to form the openings 1315 a , 1315 b , 1315 c , and 1315 d in FIG. 13 through which fluid flows out. The key or keys also ensure that tip 1701 does not rotate during the microdermabrasion session and move the channels out of alignment. In other implementations, however, it may be desirable to have a rotating tip in order to provide additional microdermabrasion action (i.e., tip rotates or spins during use).
In a specific implementation, the keys may also be used to specifically misalign certain channels in the tip holder 1601 and abrasive tip 1701 in order to not form an opening for fluid to exit. Thus, the amount of fluid exiting may be adjusted by misaligning the channels in the abrasive tip 1701 with the channels in the tip holder 1601 .
In a specific implementation where there is a particular direction of travel for the abrasive tip 1701 , the keys may also be used to ensure that the abrasive tip 1701 is properly positioned along the particular direction of travel.
Collars 1710 a , 1710 b , 1710 c , and 1710 d slide into the tip holder 1601 . The collars 1710 a , 1710 b , 1710 c , and 1710 d are positioned between the channels 1705 a , 1705 b , 1705 c , and 1705 d in the abrasive tip 1701 . This allows fluid to flow out of the openings formed by aligning the channels in the abrasive tip 1701 with the channels in the tip holder 1601 .
The number of collars may vary. Typically, the number of collars will be dependent on the number of channels. For example, if there are four channels, then there will be four collars. However, this is not always the case. In other implementations, the number of collars will be different from the number of channels. There may be more channels than collars, or there may be fewer channels than collars.
As shown in the cross-sectional view in FIG. 18 , the collars 1710 a , 1710 b , 1710 c (not shown) and 1710 d (not shown) help to support the abrasive tip 1701 in the tip holder 1601 . In a specific implementation, the abrasive tip 1701 is held in tip holder 1601 using a friction fit between the collars and the tip holder 1601 . The pressure of the abrasive tip 1701 against the skin and the vacuum in annular space 1604 also helps to hold the abrasive tip 1701 in the tip holder 1601 .
However, in other implementations, other types of fastening interfaces may be used. For example, the abrasive tip 1701 may be held in the tip holder 1601 using magnets, a snap fit (e.g., cantilever snap fit), threads, a screw or screws, or combinations of these. When using a snap fit interface, for example, a ridge may be located on one or more of the collars. This ridge may then snap into a recess in tip holder 1601 .
When using a screw, for example, the screw may be inserted through the abrasive tip 1701 and threaded into a plate in located in tube 1603 . In this particular implementation, the screw is typically recessed into the abrasive tip 1701 . This ensures that the head of the screw does not scrape the patient's skin.
The type of drive design on the screw may vary. For example, the drive may be slotted, a Phillips, a Pozidriv, a torx, a hex, a Robertson, a tri-wing, a Torq-set, a spanner head, or a triple square.
In a specific implementation, a plate in tube 1603 that the screw threads into will still allow fluid to pass though. This may be accomplished where, for example, the plate is a cross bar that spans the inner walls of tube 1603 . In this case, fluid would pass around the cross bar. In another implementation, the plate may contain perforations that allow fluid to pass through. In yet another implementation, the plate may be smaller than the cross-sectional area of the tube 1603 and be held in place with one or more supporting spokes attached to the inner walls of the tube 1603 .
The screw may come into contact with fluids. Thus, in a typical implementation, the screw will be made of a material that will not react with the fluids. For example, the screw may be stainless steel, zinc coated steel, galvanized steel, aluminum, or plastic. The screw may be metric or English threaded.
FIG. 18 also shows that abrasive tip 1701 is recessed into tip holder 1601 by a distance d. This allows, for example, the skin to be pulled into opening 1420 in order to seal opening 1420 and have the skin contact abrasive tip 1701 . Distance d may range from about 0.01 millimeters to about 2 millimeters. This includes, for example, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, or more than 2 millimeters. In other implementations, d may be less than 0.01 millimeter.
FIG. 19 shows the front of abrasive tip 1701 and tip holder 1601 . Annular space 1604 surrounds abrasive tip 1701 . In a specific implementation, the surface of abrasive tip 1701 may be formed by fusing (e.g., gluing, imbedding) abrasive particles to the surface. Examples of abrasive coatings could include diamond, silicone carbide, magnesium oxide, aluminum oxide, and the like, or combinations of these. The abrasive surface may also be formed by applying an adhesive-backed paper substrate to the surface, knurling, machining, laser treatment or otherwise mechanically or chemically treating the surface. The abrasive surface may also include an abrasive open screen with bonded abrasive particles.
The abrasive particles are generally of a size ranging from about 50 grit to about 300 grit, including for example, 100 grit and 120 grit. The abrasive particles may be carborundum (aluminum oxide) or sodium bicarbonate, or other, or combinations of these. The coarser particles (at the lower ends of the grit ranges) may be provided for use in initial treatments, while finer particles (at the higher ends of the grit ranges) may be employed for later treatments.
In a specific implementation, the abrasive tip 1701 is intended for single-use only. This is because debris, such as skin particles, may become lodged within the abrasive tip 1701 . The debris may reduce the abrasive properties of the abrasive tip 1701 . Additionally, abrasive particles may become detached from the abrasive tip 1701 . It may also be difficult to properly sanitize the abrasive tip 1701 to remove the lodged debris. In a specific implementation, abrasive tip 1701 may include structures that break-away when abrasive tip 1701 is removed from the tip holder 1601 . This safeguard ensures that the abrasive tip 1701 is not erroneously reused. This also protects patients from coming into contact with abrasive tips that have been contaminated with debris from other patients.
In another implementation, abrasive tip 1701 , the spent fluids, or both may be intended for sterilization and repeated use.
Annular space 1604 surrounds the abrasive tip 1701 . This allows spent fluids and removed skin particles to be pulled back into the vacuum in annular space 1604 . Thus, little or no spent fluids or skin particles remain on the patient's skin that will later require additional cleaning.
In a specific implementation, the surface area of the annular space may range from about 15 square millimeters to about 30 square millimeters. This includes, for example, less than 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or more than 30 square millimeters. The surface area of the annular space depends, in part, on the size of the abrasive tip 1701 . A ratio of the surface area of an annular space to the surface area of the abrasive tip 1701 may range from about 1:0.5 to about 1:5. This includes, for example, ratios of 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, 1:1.5, 1:1.6, 1:1.7, 1:1.8, 1:1.9, 1:2, 1:3, 1:4, or more than 1:5. However, in other implementations, the ratio may be less than 1:0.5.
FIG. 20A and FIG. 20B show a front view of a specific implementation of two differently sized abrasive tips 2001 , 2005 and the corresponding tip holders 2002 , 2010 . In a specific implementation where circular shaped abrasive tips and tip holders are used, abrasive tips 2001 and 2005 may have diameters of 6 millimeters (d 1 ) and 9 millimeters (d 3 ), respectively.
An opening 2011 on tip holder 2010 may likewise be larger than an opening 2003 on tip holder 2002 in order to accommodate the larger abrasive tip 2005 .
However, the outside diameters (d 2 and d 4 ) of tip holders 2002 and 2010 may be the same. This allows, the same wand 10 (see FIG. 1 ) to be used with varying abrasive tip sizes.
It should be appreciated that there may be many more sizes of abrasive tips besides the 6 millimeter and 9 millimeter diameters shown in FIG. 20A and FIG. 20B . The size or surface area of the abrasive tips may vary greatly. This depends, in part, on the skin surface to be treated.
For example, the surface area of the abrasive tips may range from about 25 square millimeters to about 350 square millimeters. Abrasive tips having smaller surface areas such as 28.3 square millimeters or 63.6 square millimeters may be used where the area to be treated is small such as a patient's cheek. The smaller abrasive tips may also offer more control when the area to be treated is adjacent sensitive areas such as around eyes or lips. Abrasive tips having larger surface areas such as 314 square millimeters may be used to treat larger areas such as arms, legs, torsos, or backs. Where, for example, circular shaped abrasive tips are used, the diameter may range from 4 millimeters to 20 millimeters. This includes, for example, less than 4 millimeters, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, 16, 16.5, 17, 17.5, 18, 18.5, 19, 19.5, or more than 20 millimeters in diameter.
The abrasive tips may also be formed in different shapes other than circles, such as, ellipses, ovals, rectangles, or squares, or any other shape that substantially maintains an annulus or other flow paths that would substantially surround the abrasive tips. The shapes may include edges that are concave, convex, curved, straight, or combinations of these.
Although this specific implementation shows two different tip holders ( 2002 , 2010 ) being used with two different sized abrasive tips ( 2001 , 2005 ), this is not always the case. For example, the tip holder 2010 for the larger abrasive tip 2005 may also be used to hold an abrasive tip that has a surface area of abrasive particles that is the same as the surface area of the smaller abrasive tip 2001 . This allows, for example, the same tip holder to be used for abrasive tips that have two different surface areas of abrasive surfaces.
FIG. 21 shows a specific implementation of an abrasive mesh tip 2105 which uses a nonwoven nylon web, such as that available from, among others, 3M Corporation. The abrasive mesh tip may be placed in the same tip holder 2002 that is used for the abrasive tip 2001 . In other implementations, the tip holder will be different. The tip holder 2001 may also be integrated with the abrasive mesh tip 2105 as a single unit.
In a specific implementation, fluid flows through the center of the abrasive mesh tip 2105 , around a perimeter of the abrasive mesh tip 2105 , or both. The mesh separates the opening for fluid from the skin so that fluid can flow out.
In a specific implementation, the abrasive mesh tip 2105 has a diameter of 6 millimeters. However, the size of the abrasive mesh tip may vary. For example, FIG. 22 shows a specific implementation of an abrasive mesh tip 2205 which has a 9 millimeter diameter.
In addition to the 6 millimeter and 9 millimeter sizes, there may be many more sizes. Where, for example, circular shaped abrasive mesh tips are used, the diameter may range from 4 millimeters to 20 millimeters. This includes, for example, less than 4 millimeters, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, 11.5, 12, 12.5, 13, 13.5, 14, 14.5, 15, 15.5, 16, 16.5, 17, 17.5, 18, 18.5, 19, 19.5, or more than 20 millimeters in diameter.
The height of the abrasive mesh tip may also vary greatly. The height is typically about 2 millimeters, but can range from about 0.4 millimeters to about 15 millimeters. For example, the height may be 0.5, 0.6, 0.7, 0.8, 0.9, 1, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 11, 12, 13, 14, or more than 15 millimeters. In other implementations, the height may be less than 0.4 millimeters.
FIG. 23 shows examples of several packaging options for the tips (e.g., smooth tips, abrasive tips, abrasive mesh tips, bristled tips) and bottles of fluid.
In a specific implementation, the tips may be individually packaged 90 , 91 . In other implementations, the tips may be provided as a kit 92 . The kit may contain identical tips, tips having different sizes, tips having different levels of abrasiveness (e.g, 100 grit, 200 grit, 300 grit) and types of abrasive elements (e.g., grit, bristle, abrasive mesh), or combinations of these. For example a kit may contain several tips with grit ranges from 100 grit to 300 grit. A microdermabrasion session may start with the most abrasive grit, such as 100 grit, in order to quickly remove large portions of skin. As the patient's skin becomes smoother, less abrasive tips may then be used to produce a smooth skin surface.
In a specific implementation, the bottles of fluid 80 may be individually packaged separate from the tips. In another implementation, multiple bottles of fluids may be packaged together 94 , separate from the tips.
In yet another implementation, a single tip or multiple tips may be packaged 93 with a bottle of fluid 80 or multiple bottles of fluid. In a specific implementation, one bottle of fluid may be equivalent to one microdermabrasion session. A single tip, intended for use for one session, may then be packaged with the bottle of fluid. The tip and bottle may be packaged in a sterile container. A user may then remove the tip and bottle from its packaging in view of the patient. This allows the patient to see that a new tip is being used. It also allows the patient to see that the fluid in the bottle has not been tampered or diluted.
This description of the invention has been presented for the purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form described, and many modifications and variations are possible in light of the teaching above. The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications. This description will enable others skilled in the art to best utilize and practice the invention in various embodiments and with various modifications as are suited to a particular use. The scope of the invention is defined by the following claims. | An abrasive tip is used to exfoliate skin and tissue through abrasive materials integrated in the tip. The tip also delivers fluid to the skin and vacuums the fluid and abraded tissue during treatment. Treated skin will look younger and healthier in appearance. In an implementation, the tip is replaceable and disposable. | 0 |
This is a continuation of application Ser. No. 660,672 filed Oct. 15, 1984 now abandoned.
BACKGROUND OF THE INVENTION
The present invention relates to ball valves, and more particularly to a block-type ball valve which is designed to firmly retain the ball of the valve within the valve body.
As an example of conventional ball valves, a so-called "union-type ball valve" is known in which a ball is arranged in a cylindrical valve body in such a manner that it can open and close a fluid passage therein. Annular seals abut against the ball from both sides in the fluid passage, the annular seals being urged towards the ball by seal carriers. In the ball valve, when connecting sleeves are connected to the valve body, the connecting sleeves push the seal carriers towards the ball. The seal carriers are pushed by the connecting sleeves which are connected to the valve body, for instance, with union nuts, so that the abutment pressures of the annular seals to the ball can be adjusted by tightening or loosening the union nuts. Therefore, when the annular seals wear to the extent of causing leakage of fluid, the leakage can be eliminated by further tightening the union nuts.
The most serious drawback of a ball valve of this type is that, under the condition that the ball closes the fluid passage and the fluid pressured is applied, the union nut and the connecting sleeve on the other side cannot be removed. In order to repair or replace the pipe line connected to the connecting sleeve, it is necessary to loosen the union nut thereby to remove the connecting sleeve. However, if the connecting sleeve is removed, the ball and the seal carrier may blow out of the valve body due to the fluid pressure. Thus, the removal of the connecting sleeve under this condition is dangerous.
In order to eliminate this drawback, a ball valve, as disclosed by U.S. Pat. No. 3,550,902, for instance, has been proposed in which one seal carrier is provided on only one side of the ball while the other seal carrier is made integral with the valve body. With this valve, piping is performed with the seal carrier faced towards the side to which the pressure is applied. However, the ball valve is still disadvantageous due to the fact that the adjustment to compensate for wear of the annular seals is carried out by further tightening only one of the union nuts. If tightening is repeatedly carried out in this manner, the center of the ball will be significantly displaced from the center axis of the spindle. As a result, the torque required for turning the handle to turn the ball thereby to open and close the valve is increased; that is, the valve cannot be smoothly opened and closed. If the handle is forcibly turned, the spindle is pushed from one side only, as a result of which leakage occurs at the seals around the spindle.
U.S. Pat. Nos. 4,327,895 and 4,449,694 and Japanese Utility Model Application No. 105474/1982 disclose ball valves in which a seal carrier is screwed into the valve body in order to prevent the seal carrier from blowing out of the valve body. U.S. Pat. No. 4,059,250 discloses a valve ball in which a seal carrier having dogs along the periphery thereof is turned after being pushed into the valve body so that the dogs are engaged with lips formed in the bore at each end of the valve body in order to prevent the seal carrier from blowing out of the valve body. However, employment of the above-described methods of screwing the seal carrier into the valve body or turning the seal carrier after pushing into the valve body it is necessary to use a special tool. Furthermore, the ball valve becomes intricate in construction, and accordingly the valve assembly and disassembly operations are time consuming.
U.S. Pat. No. 3,807,692 discloses a ball valve which is formed by injection molding a valve body with synthetic resin, with pre-fabricated ball integrally with a spindle and annular seals in the mold cavity. In accordance with this method, because the ball is surrounded by the valve body, even when the connecting sleeve is removed by loosening the union nut, the ball cannot blow out of the valve body. However, the ball valve is still disadvantageous in that, since the annular seals together with the ball are insertedly molded in the valve body, further adjustment of the abutment pressures of the annular seals to the ball cannot be done, and if the annular seals are worn to the extent of causing leakage, uneconomically, the valve must be replaced in its entirety.
SUMMARY OF THE INVENTION
Accordingly, an object of the invention is to eliminate the above-described difficulties accompanying a conventional ball valve.
In accordance with the above and other objects, the invention provides a ball valve which is provided with a mechanism for further tightening annular seals in a union-type ball valve, and a mechanism for preventing the ball from blowing out in the ball valve which is integrally molded with a ball, so that, even if the connecting sleeve is removed by loosening the union nut, the ball and the annular seals cannot blow out of the valve body, and the abutment pressures of the annular seals to the ball can be adjusted by further tightening the union nut to prevent the leakage of fluid.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a vertical sectional view showing an example of a ball valve according to the invention;
FIG. 2 is a cross-sectional view taken along a line II--II in FIG. 1;
FIGS. 3, 4 and 5 are cross-sectional views similar to that of FIG. 2, showing modifications of the ball and valve body shown in FIGS. 1 and 2; and
FIG. 6 is a cross-sectional view taken along a line VI--VI in FIG. 1.
FIG. 7 is a cross-sectional view similar to that of FIGS. 2, 3, 4 and 5, showing a further modification of the ball and valve body of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
A ball valve constructed according to the invention will now be described with reference to the accompanying drawings.
FIG. 1 is a vertical sectional view showing an example of the ball valve of the invention, and FIG. 2 is a cross-sectional view taken along a line II--II in FIG. 1. In these figures, reference numeral 1 designates a valve body; 2, a ball; and 3 and 4, seal carriers. Through-bores 21, 31 and 41 of substantially equal inside diameters are formed in the ball 2 and the seal carriers 3 and 4, respectively. These through-bores form a passage for fluid.
The ball 2 formed integrally with a spindle 5 is inserted in the valve body 1 with the spindle 5 protruding outside the valve body 1. The ball 2 is pivotally held with its external surface including the spindle 5 in contact with an annular seat 11 formed in the inner wall of the valve body 1. By turning a handle 6 secured to the spindle 5, the ball 2 on the seat 11 can be turned to open or close the fluid passage. Since the ball 2 is held with its external surface in contact with the annular seat 11, the ball 2 will not come off the seat 11 even when the fluid pressure in the fluid passage acts on the ball 2.
The seat 11 is formed by, in molding the valve body, by injection molding machine, holding the ball in place in the mold cavity, and applying molten resin directly to the surface of the ball thus held. The configuration of the seat 11 may be changed by using a mold with appropriate configuration. However, a ball valve in which, as shown in the figures, the ball 2 is pivotally supported by the entire inner surface of the valve body 1 has an advantage that the gap (dead space) between the ball 2 and the inner wall of the valve body 1 is small, and therefore the amount of so-called "dead water" is reduced as much.
An O-ring 51 is inserted between the spindle 5 of the ball and the bearing part 12 of the valve body 1. The O-ring 51, retained by a bushing 52, serves as a seal around the spindle.
Annular recesses 32 and 42 are formed on the sides of the seal carriers 3 and 4 adjacent to the ball 2, respectively. Annular seals 33 and 43 are fitted in the recesses 32 and 42, respectively. By pushing the seal carriers 3 and 4 towards the ball 2, annular seals 33 and 43 are pushed against the ball 2 to maintain the fluid passage sealed.
In order to push the seal carriers 3 and 4 towards the ball 2, the structure of the ball valve is of a conventional union type such that connecting sleeves 7 adapted to connect pipes are set on the outer end faces of the seal carriers 3 and 4, and are then secured by screwing union nuts 71 onto threads formed on the exterior surface of two cylindrical end portions of the valve body 1.
Under the condition that the seal carriers 3 and 4 are pushed towards the ball 2, gaps are present between the two end faces of the valve body 1 and the connecting sleeves. Therefore, the abutment pressures of the annular seals 33 and 43 against the ball 2 can be adjusted by further tightening the union nuts 71.
In these figures, reference numerals 34 and 44 designated O-rings provided between the valve body 1 and the seal carriers 3 and 4, respectively; and 35 and 45, O-rings provided between the seal carriers 3 and 4 and the connecting sleeves 7, respectively.
Further in the figure, reference numerals 36 and 46 designate elastic packings provided between the seal carriers 3 and 4 and the seats 11, respectively. The packings 36 and 46 are preferably set compressed because, if the annular seals 33 and 43 are worn so as to contact the outer surface of the ball nonuniformly, or when the ball 2 is turned to open or close the valve, the packings elastically push the seal carriers 3 and 4 towards the connecting sleeves 7, and therefore maintained are uniform sealing of the O-rings provided between the seal carriers 3 and 4 and the connecting sleeves 7, and between the ball 2 and annular seals 33 and 43.
The above-described ball valve is installed in piping as follows: Pipes are connected to the connecting sleeves 7 and the valve body 1 is set between the connecting sleeves 7. Under this condition, the union nuts 71 are engaged with the threaded parts of the two end portions of the valve body 1. When it is necessary to replace the ball seat or the pipe, the ball 2 is turned to close the valve, and then the union nut 71 is removed. Under this condition, the pipe is disconnected to replace the ball seat or the pipe. As the ball 2 is held in contact with the substantially spherical concave seat 11, the ball 2 cannot blow out even when liquid pressure is applied to the ball from one side thereof. Even if leakage occurs, it can be eliminated by further tightening the union nuts 71.
FIGS. 3 through 5 show modifications of the ball and seat in the valve body of the ball valve according to the invention. In these modifications, those components which have been previously described with reference to FIG. 1 are designated by the same reference numerals.
In the modification in FIG. 3, the seats 11a are formed so that they contact only the parts of the ball surface which are located around the axis of the spindle. In other words, the ball 2 is pivotally supported by the seat 11a at two positions where the spindle 5 crosses the valve body. It is desirable for the seats 11a to be as large as possible under the condition that they do not obstruct the provision of the annular seals 33 and 43.
In the case of FIG. 4, only the part of the ball surface which is located around the spindle axis and on one side of the ball which is opposite to the side where the spindle 5 is provided is in surface contact with a seat 11b, and the step of the spindle 5 is engaged with the step of the valve body 1 to rotatably support the ball 2. In this connection, the step of the spindle 5 may be locked to the valve body 1 with a locking ring which is threadably engageable with the valve body, similar to the case of the bushing 52 in FIG. 1. The ball is pivotally supported only around the spindle axis, as described above. Therefore, the frictional resistance for turning the ball is smaller, as a result of which the ball can be smoothly turned to open or close the valve. In addition, in molding the valve body 1 with the ball 2 inserted, the molten resin does not contact the surfaces of the ball 2 which slide on the annular seals 33 and 43. Accordingly, the surface of the ball 2 is maintained smooth.
The ball valve of the invention may be modified so that, as shown in FIG. 5, a protrusion 53 extends from the part of the ball surface which is located around the spindle axis and on one side of the ball which is opposite the side where the spindle 5 is provided. The protrusion 53 is in surface contact with a seat 11c formed in the valve body 1. It is preferable that the protrusion 53 be in the form of a circular cone or a frustrum of circular cone. The protrusion 53 may be pivotally supported by only the surface of the seat 11c. Furthermore, the ball valve may be modified so that, instead of the protrusion 53, a recess is formed in the surface of the ball 2 and a protrusion extends from the seat engaging the recess. In a valve in which the protrusion extends from the surface of the ball 2 or the recess is formed in the surface of the ball, the ball 2 is pivotally supported by the valve body 1 with a high concentricity.
A variety of modifications of the seat 11 are possible as described above. However, in the ball valve of the invention, at least a part of the ball surface located around the spindle axis and on the side of the ball 2 opposite the side where the spindle 5 is provided should be in surface contact with the seat.
In the described invention, the valve body 1 is injection molded with the ball 2 inserted in the mold cavity. In this connection, the gate of the mold is generally positioned where the seat is formed, especially at the position where symmetrical flows of molten resin are obtained. Therefore, the temperature of the surface of the ball 2 near the gate is raised when the molten resin contacts the ball 2. Accordingly, in the case where the ball 2 is made of synthetic resin, the surface of the ball 2 may be deformed. However, this difficulty can be eliminated by providing a heat-resistant layer of metal or fluororesin such as tetrafluoroethylene resin on the surface of the ball 2 confronting the gate.
In accordance with the invention, the ball 2 may be made of metal or synthetic resin; however, synthetic resin is preferable from the viewpoint of chemical resistance. Furthermore, since the ball should have a high heat resistance, it is desirable that it be made of polyvinyl chloride resin, preferably chlorinated polyvinyl chloride resin, and more preferably, polyvinyl chloride resin compounded with graphite or chlorinated polyvinyl chloride resin compounded with graphite. Chlorinated polyvinyl chloride resin of 100 parts by weight containing chlorine of 63 to 71 percent by weight and graphite of 2 to 20 parts by weight is most preferable because of its high heat resistance. This material can be molded although its chlorine content is high. The valve body 1 is formed of a moldable material such as polyvinyl chloride resin or the like.
In the invention, the handle 6 and the valve body 1 form a locking mechanism so that the ball 2 is allowed to turn through 90° in one direction to fully open the valve from the closed position shown in FIG. 6.
The locking mechanism of the handle 6 will be described with reference to FIG. 6. The upper end portion of the spindle 5 is formed into a cross-shaped fitting protrusion 54 which is fitted into a cross-shaped recess 61 formed in the handle 6. Therefore, the spindle 5 can be turned with the handle 6. An annular projection 13 with a cut extends from the upper surface of the annular bearing part 12 of the valve body 1, while a stop 62 is formed in the handle 6 engaging with the cut of the projection. Therefore, the handle 6 can be turned through an angle which is defined by both ends of the cut between which the stop 62 is moved.
If the positions where the stop 62 strikes the two ends of the cut of the projection 13 are determined so that the valve is opened when the handle 6 is set in the direction of the fluid passage and the valve is closed when the handle is set in a direction perpendicular to the direction of the fluid passage, then it can be detected from the direction of the handle 6 whether the valve is opened or closed.
With the ball valve of the invention designed as described above, the part of the ball surface around the spindle axis and on the side of the ball opposite the side where the spindle is provided is in surface contact with the seat of the valve body to pivotally support the ball; that is, the ball is held in surface contact with the seat. Therefore, even under the condition that the valve is closed and liquid pressure is applied to the ball from one side, when the union nut on the other side is loosened, the ball will not blow out.
The ball abuts against the annular seals on both sides in the fluid passage, and the annular seals are pushed towards the ball by the seal carriers. Therefore, if fluid leakage occurs, such can be eliminated by further tightening the union nuts to push the seal carriers towards the ball. Furthermore, if the annular seal is damaged, it is possible to replace only the annular seal. Thus, the ball valve of the invention is economical. | A ball valve in which, even when a connecting sleeve is removed by loosening the associated union nut, the ball and annular seals of the valve will not blow out of the valve body under fluid pressure. A ball with an integral spindle is arranged in the valve body in such a manner as to be able to open and close a fluid passage therein. A seat is formed in the valve body and a part of the surface of the ball on the side thereof opposite the side where the spindle is provided and around a rotational axis of the spindle is in surface contact with the seat to thereby pivotally support the ball. Annular seals are provided in the fluid passage abutting against the ball from both sides to pivotally support the ball with the annular seals being urged towards the ball by seal carriers. | 5 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to the drilling of wells offshore; and, more particularly, to a method and apparatus for producing hydrocarbons from subterranean formations under the ocean floor.
2. Description of the Prior Art
In an attempt to locate new oil fields, an increasing amount of well drilling has been conducted at offshore locations, such as off the coasts of California, Louisiana, and Texas, and more recently, off the coast of Alaska and in the North Sea. Generally, well drilling structures used at these locations are installed above the surface of the offshore body of water, these structures being supported by columnar frames extending downward to the bottom of the body of water. Straight well conductors generally comprising hollow sections of pipe are extended from these well drilling structures some distance below the ocean floor. These conductors provide guidance and support for tubular well drilling equipment carried within these conductors and used for drilling into hydrocarbon bearing reserves.
As the water depths of the drilling operations increase the cost of these bottom supported well drilling structures becomes prohibitive. For this reason, Tension Leg Platforms, comprising moored floating vessels, or dynamically positioned floating vessels are used in these greater water depths. Wells drilled from these devices are guided through a well conductor template placed below these devices on the ocean floor. This template, generally a massive structure, allows the placement of straight well conductors down through well conductor guides carried by the template, such as disclosed in FIG. 1 of U.S. Pat. No. 4,198,179, entitled "Production Riser," filed Aug. 11, 1978 and issued Apr. 15, 1980 to Floyd T. Pease, et al.
As can be imagined, these structures are expensive, and the number of hydrocarbon bearing reservoirs that may be laterally reached beneath each structure needs to be maximized. But the lateral reach of the well conductors is limited by the vertically oriented well conductor guides carried by the well template. Since the well conductors pass vertically through the well template, wells drilled through these well conductors cannot developed an angle of inclination sufficient to reach distant hydrocarbon bearing formations.
To increase the lateral reach of the wells drilled from the bottom supported marine structures mentioned earlier, curved well conductors were sometimes used as is disclosed in U.S. Pat. No. Re. 28,860, entitled "Curved Offshore Well Conductors", reissued June 15, 1975 to Peter W. Marshall et al. By curving these conductors, the well drilling equipment could develop an angle of inclination from the vertical before leaving the curved conductor. Since the drilling equipment would also develop an early angle of inclination, more distant reservoirs located at a greater lateral distance beneath the marine drilling structure could be reached.
It would be desirable therefore, to also incorporate these curved well conductors into the well templates in order to maximize the lateral reach of the well drilling equipment.
But the probability of successfully aligning and installing curved well conductors into a well template located a substantial distance below a floating drilling vessel must be viewed with apprehension. Poor visibility and strong currents, as well as roll, pitch, heave, and sway of the surface vessel must necessarily complicate the operation.
A method and apparatus needs to be developed which allows the installation of curved well conductors into a subsea well template, in order to maximize the possible economic recovery of hydrocarbon reserves located beneath these well templates.
SUMMARY OF THE INVENTION
The present invention describes a method and apparatus to be used in the installation of curved well conductors into a subsea well template. The upper surface of the well template incorporates an arrangement of cooperating surfaces that aids in aligning and guiding the lower end of the curved well conductor towards a conductor guide opening located through the upper surface of the well template.
Specifically, the Well Template apparatus of the present invention, comprises, well conductor movement limiting means formed by a substantial portion of the upper surface of the well conductor template, said surface arranged to prevent, during installation of at least one well conductor, said well conductor from downward vertical movement and lateral movement toward the vertical central axis of said well template, and curved conductor guide means carried by said conductor template and forming an opening curved therethrough, for slideably receiving a well conductor passed downwardly therethrough.
More specifically, the method of the present invention for producing hydrocarbons from a subterranean hydrocarbon-bearing formation located beneath the floor of a body of water comprises the steps of; installing a well conductor template having a vertical central axis, said template carrying at least one curved conductor guide means, on the floor of said body of water above said formation, lowering a well conductor downwardly through said body of water, the well conductor contacting well conductor movement limiting means formed by a substantial portion of the upper surface of said well template, thereby preventing said well conductor from downward vertical movement and lateral movement toward the vertical central axis of said well template, aligning the lower end of said well conductor with an open upper end of said curved conductor guide means, extending said well conductor downwardly with respect to said well conductor template, through said curved conductor guide means, thereby curving said conductor outwardly and downwardly through said template in a manner maintaining a relatively smooth bore throughout substantially the entire extent of said conductor, drilling a well via said conductor down through said floor and into fluid communication with said formation, and producing formation fluids from said formation via said well conductor.
An object of the present invention is to install curved well conductors in subsea well templates. A further object is to simplify the installation of these conductors into the subsea template.
These and other features and advantages of the present invention will become apparent from the following detailed description, wherein reference is made to the Figures in the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a subsea well template located on a bottom of a body of water.
FIG. 2 is a schematic view in cross section taken along lines 2--2 of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to both FIGS. 1 and 2, a floating vessel 17 is shown floating in a body of water 12. A well conductor template 10 is located beneath said vessel 17, said template 10 resting upon the floor of the bottom of water 20. Whereas a floating vessel 17 is shown, it is recognized that a tension leg platform well known to the art may also be used for the operations to be subsequently described. These operations utilizing a well conductor template 10 are typically conducted in the deeper water depths of the body of water 12.
An observation vehicle 16 is shown positioned adjacent the well conductor template 10 in order to send visual signals through the communication cable 27 to the vessel 17. This visual information is used as an aid in positioning the vessel 17 in order to correctly align a well conductor 26 suspended by a cable 28 from a derrick 19 carried by the vessel 17. The well conductor 26, typically a tubular section having an opening defined therethrough along the longitudinal axis of the section, is shown in FIG. 2 as a straight section. It is recognized, however, that the well conductor 26 may be preformed or prebent to aid the assembly of the well conductor 26 through the well conductor template 10. The well conductor 26 is shown initially contacting the sheathing 34 which forms the upper surface of the well conductor template 10. This sheathing 34 may take the form of plate steel or prestressed concrete sections fabricated and constructed by methods well known to the art.
An underwater wellhead assembly 13 is shown positioned upon a horizontal member 30 of the well conductor template 10. A flow line 15 is shown connected to the underwater wellhead assembly 13. The underwater wellhead assembly 13 can also be mounted on the deck of the vessel 17 with a production riser (not shown) extending downwardly from the vessel 17 to the template 10, in order to transmit reservoir fluids from beneath the well conductor template 10 to the vessel 17 for further processing by methods well known to the art.
A series of sonar transmitters 29 may be located about the well conductor template 10 in order to help position the vessel 17 above the template 10. It is also recognized that a sonar transmitter 29 or TV camera (not shown) may be mounted on the conductor 26 while it is being lowered to aid in guiding it into the subsea template 10.
The configuration of the well conductor template 10 permits easy directional guidance of the well conductors 26 to any of the four sides of the template 10. Note that a circular template or other geometric configuration may also be used. The pyramid shape of the well conductor template 10 prevents mud and silt buildup at the lower elements and also elevates the interior conductors 26 located adjacent or closer to a vertical central axis 37 to allow a greater angle of inclination of the interior conductors 26 when leaving the template 10. For example, once the conductors 26 are installed within the template 10, the conductors 26 located closer to the central axis 37, due to their increase length, can develop an angle of inclination 39 of their lower elements located adjacent the lower elements of the template 10, greater than an angle of inclination 38 developed by the shorter well conductors 26 located further from the vertical axis 37. In an alternative embodiment if different vertical heights are not desired or are not required the top of the template 10 could be flat and not require the sloping sides of the sheathing 34.
Note that at least one of the well conductors 26 is shown extending outwardly and downwardly with respect to the lower elements of the well conductor template 10, although it is recognized that the conductors 26 may be terminated at the base of the template 10.
During installation of the well conductors 26, the upper sheathing 34 of the template 10 forms well conductor movement limiting means 33. These movement limiting means 33 include at least one horizontal member 30 and at least one inclined member 32, an inclined member also including, for example, a vertical member 31 if necessary. The horizontal member 30 forms a planar surface having openings defined therethrough. Landing shoulders 41 are formed around these openings, these landing shoulders 41 typically taking the geometric configuration of funnels in order to assist in lowering the lower end of well conductor 26 down through the template 10. The landing shoulders 41 are operatively engaged to an upper portion of conductor guide means 23.
These conductor guide means 23 are carried by the template 10 and constructed so as to form an opening curved down through the template 10 in order to slideably receive the well conductor 26. These conductor guide means 23 may also be used to bend a straight well conductor 26 as it is forced down through the template 10 such as by an underwater pile driving apparatus (not shown) attached to the upper end of the conductor 26. These means 23 may take the form of discrete guide units 24, such as rings, welded to members of the framework 35 of the well conductor template 10, or these conductor guide means 23 may take the form of a single unitary guide pipe 36 which can be curved and preformed and then secured to the interior of the template 10. If discrete guide units 24 are utilized, they are typically spaced vertically apart in substantial vertical alignment and are deviated horizontally from a vertical alignment so as to define an arcuate center line through the centers of said guide units 24. The guide pipes 36 are also deviated horizontally from a vertical alignment to define an arcuate center line.
The well conductor movement limiting means 33 formed by a substantial portion of the upper surface or sheathing 34 of the well conductor template 10, is arranged during installation of at least one well conductor 26, to prevent that well conductor from downward vertical movement and/or lateral movement toward the vertical central axis 37 of the well template 10. To accomplish this result, the horizontal member 30 is typically operatively connected to an inclined member 32, the arrangement of both members 30 and 32 assisting the installation alignment of the lower end of the well conductor 26 with the open upper end of said conductor guide means 23.
Once the conductor 26 is installed through the template 10, it can be seen to define an arcuate center line 25 through at least a portion of the template 10. A conductor 26 vertical section 42 may be utilized at any convenient point to correctly align the conductor 26 toward a targeted reservoir located beneath the body of the water floor 20. In any event, the conductors 26 are prebent or bent by the template 10 in such a fashion as to have a relatively smooth bore throughout the entire extent thereof. Note that the well template 10 may be installed upon the body of water floor 20 with or without at least some well conductors 26 fabricated within the framework 35 of the template 10. Note that all conductors 26 have a portion curved outwardly, and all conductors 26 also extend downwardly through the well conductor template 10 and are positioned during passage through the template within the plan view periphery of the template 10.
The height of the well conductor template 10 will typically be less than the water depth that the template is submerged in. A conductor 26 may also be used as pile means 21 in order to supply sufficient anchoring means for anchoring the template 10 to the floor of the body of water 12. Means carried by said template 10 for receiving these pile means 21 may take the form of the conducter guide means 23 used to assist in positioning the conductors 26 through the structure 10.
Whether the well conductors 26 are used to assist in well drilling operations or as merely a pile means 21 to anchor the template 10 to the ocean floor 20, it can be seen that the curved conductor guide means 23 can sufficiently deviate the well conductor 26 up to an allowable curvature of 6° without deleterious effects to drilling and/or pile driving operations. Above an angle of 6° chafing of the drillstring (not shown) rotating within a conductor 26 upon the interior wall of the conductor 26 may cause separation of the drillstring with subsequent loss of time during field production development. It is well recognized that curvature angles less than 6° may be used in the fabrication and installation of any well conductor 26 within the template 10.
The method for producing hydrocarbons from a subterranean hydrocarbon-bearing formation located beneath the floor of the body of water 20 can be accomplished by using the aforementioned apparatus in the following manner. First, the well conductor template 10 having a vertical central axis and carrying at least one curved conductor guide 23 means is installed on the floor of the body of water 12. Then, a well conductor 26 is lowered downwardly through the body of water 12. The well conductor 26 eventually contacts the well conductor movement limiting means 33 formed by a substantial portion of the upper surface of the well template 10. Contact of the well conductor 26 with these movement limiting means 33 prevents the conductor 26 from further downward vertical movement and/or further lateral movement toward the vertical central axis 37 of the template 10. At this point, the lower end of the well conductor 26 is aligned with an open upper end of the curved conductor guide means 23. As before, these guide means 23 may take the form of discrete guide units 24 or a guide pipe 36 as discussed earlier.
The step of lowering at least one well conductor 26 downwardly through the body of water 12 includes providing a floating vessel 17 with lowering means 28 such as drill pipe or cable (not shown) well known to the art, to lower the well conductor 26 down through the body of water 12. As the conductor 26 is lowered, the position of the lower end of the conductor 26 may be monitored by the observation vehicle 16 or by a Televison camera (not shown) mounted on the conductor 26, as the lower end approaches the well conductor template 10. A sonar transmitter 29 may also be mounted on the lower end of the conductor 26. The position of the vessel 17 may be adjusted by the actuation of directional positioning thrusters 18 or mooring lines (not shown) so that the lower end of the conductor 26 contacts the well conductor template 10 as close as possible to a desired conductor guide means 23. These guide means 23 define an opening through a substantially horizontal member 30 which forms a portion of the upper surface of the conductor template 10. The position of the vessel 17 and length of the lowering means 28 may be readjusted until the lower end of the well conductor 26 aligns with and enters the opening defined by the conductor guide means 23.
Once the well conductor 26 is aligned with the conductor guide means 23 opening, the well conductor 26 may be extended downwardly with respect to the well conductor template 10 through the conductor guide means 23. The conductor 26 therefore curves outwardly and downwardly through the template 10 in a manner maintaining a relatively smooth bore throughout substantially the entire extent of the conductor 26.
The conductor 26 is curved through the template 10 by providing conductor guide means 23 at a plurality of spaced locations on the conductor template 10 adapted to curve the conductor 26. Extending the conductor 26 into communication with these guide means 23 curves the conductor 26. Of course, the step of curving the conductor 26 may include the step of preforming the desired curvature in the conductor 26 prior to the step of extending the conductor 26 downwardly with respect to the well conductor template 10. As mentioned earlier, the conductor may be curved up to approximately 6° every 100 feet.
In addition to extending one well conductor 26 downwardly with respect to said well conductor template 10, a plurality of well conductors 26 may be extended downwardly into said well template 10, these conductors 26 subsequently spaced at varying distances from the central vertical axis 37 of the template 10. At least one conductor 26 located adjacent the vertical central axis 37 will have a longer length measured through the well template cross section 10 than shorter length conductors 26 located further from the central axis 37 of the template 10, since the well template 10 in the preferred embodiment has a maximum height at its central axis 37. The elements of this longer length conductor which are located adjacent the lower elements of the template 10, will have a greater angle of inclination 39 from the vertical than the shorter length conductors 26 elements which are also located adjacent the lower elements of the template 10. In the preferred embodiment, at least one of the conductors 26 may be extended outwardly and downwardly with respect to the lower elements of the well conductor template 10.
Once the well conductors 26 are installed within the template 10, wells may be drilled via the conductor 26 down through said floor 20 and into fluid communication with hydrocarbon bearing formations (not shown). Formation fluids (not shown) may be produced from these hydrocarbon bearing formations via the well conductor 26.
Many other variations and modifications may be made in the apparatus and techniques hereinbefore described, both by those having experience in this technology, without departing from the concept of the present invention. Accordingly, it should be clearly understood that the apparatus and methods depicted in the accompanying drawings and referred to in the foregoing description are illustrative only and are not intended as limitations on the scope of the invention. | An anchored submerged marine structure commonly referred to as a well template is located at the bottom of a body of water and used in the directional drilling of underwater wells. The well template carries curved well conductors, each conductor capable of deviating well drilling equipment passed through the conductor so that each well may reach reservoirs located a further distance away from the template. The template's upper surface is formed to aid in the installation of the well conductor through the template. | 4 |
This is a continuation of application Ser. No. 11/798,239 filed May 11, 2007 now U.S. Pat. No. 7,439,506, which is a continuation of application Ser. No. 11/319,279 filed Dec. 29, 2005, U.S. Pat. No. 7,232,996, which is a continuation of application Ser. No. 11/108,877 filed Apr. 19, 2005, U.S. Pat. No. 7,012,252, which is a continuation of application Ser. No. 10/083,481 filed Feb. 27, 2002, U.S. Pat. No. 6,987,265, which is a continuation of application Ser. No. 09/883,184, filed Jun. 19, 2001, U.S. Pat. No. 6,452,178, which is a continuation of application Ser. No. 09/131,383 filed Aug. 7, 1998, U.S. Pat. No. 6,348,690.
FIELD OF THE INVENTION
In general, the present invention relates to an inspection method using an electron beam and an inspection apparatus adopting the method. More particularly, the present invention relates to an inspection method using an electron beam suitably for inspecting a pattern such as a circuit on a substrate in a process of fabricating a semiconductor device and an inspection apparatus adopting the method.
BACKGROUND OF THE INVENTION
There exists an apparatus for observing a specimen by using an electron beam which is known as a scanning electron microscope referred to hereafter simply as an SEM. In addition, as one of apparatuses for inspecting a semiconductor device, there is known a scanning electron microscope for length measurement referred to as a length measurement SEM. However, while the ordinary SEM and the length measurement SEM are suited for observation of a limited field of vision at a high magnification, they are unsuitable for finding the location of a defect on a wafer. This is because, in order to find the location of a defect on a wafer, it is necessary to search an extremely large area of the wafer or the entire surface of the wafer with a high degree of scrutiny. It takes a very long time to search such an extremely large area by using an ordinary or length measurement SEM because the current of the electron beam thereof is small, resulting in a slow scanning speed. As a result, if such SEMs are used in a process to fabricate a semiconductor device, the time it takes to complete the processing steps becomes very long, making the SEMs apparatuses of no practical use.
As an apparatus used for solving the problems described above, there is known an inspection apparatus using an electron beam for detecting a defect on a wafer by comparison of pictures. The apparatus is characterized in that: a large current electron beam is used; a specimen stage is continuously moved while the electron beam is being radiated to a specimen; a high acceleration voltage is used to accelerate the electron beam generated by an electron source; a retarding voltage is applied to the specimen to reduce the speed of the electron beam so as to prevent the specimen from being electrically-charged; and charged particles emanating from the specimen due to the radiation of the electron beam are detected after passing through an objective lens in a so-called TTL (through the lens) system.
As a result, the apparatus described above allows a mask or a pattern on a wafer serving as a specimen to be inspected for a defect with a higher degree of efficiency than the conventional SEM. It should be noted that this related technology is disclosed in documents such as Japanese Patent Laid-open No. Hei 5-258703.
With the TTL system whereby charged particles emanating from a specimen are detected after passing through an objective lens, the distance from the specimen to the objective lens can be shortened. As a result, the objective lens can be used at a short focal distance, allowing the amount of aberration of the electron beam to be reduced and, hence, a high-resolution picture to be obtained. On the other hand, the TTL system brings about unnegligible problems such as a hindrance to the improvement of the scanning speed and a big rotation change of the electron beam accompanying a variation in specimen height, causing a resulting picture to rotate as well.
FIG. 13 is a diagram showing a relation between the retarding voltage and the efficiency of detection of secondary electrons. Curve ( 2 ) shows a relation for the TTL system. As shown by curve ( 2 ), the TTL system has a problem that, as the retarding voltage is reduced, the efficiency of detection of secondary electrons also decreases to such a small value that the problem caused by a low detection efficiency can not be ignored anymore. Secondary electrons emanating from a specimen converge after passing through a magnetic field of an objective lens. The position of convergence in the axial direction changes when the retarding voltage is modified due to a variation in electron beam radiation energy. This phenomenon is the main reason why the efficiency of detection of secondary electrons decreases.
SUMMARY OF THE INVENTION
It is thus a first object of the present invention to provide an inspection method capable of increasing the speed of scanning a specimen using an electron beam and an inspection system adopting the method.
It is a second object of the present invention to provide an inspection method using an electron beam resulting in a small picture rotation and an inspection system adopting the method.
It is a third object of the present invention to provide an inspection method using an electron beam resulting in a small change in efficiency of detection of charged particles and an inspection system adopting the method.
In a configuration of the present invention, an electron beam generated by an electron source is converged on a specimen by means of an objective lens; the specimen is scanned by using the electron beam; and charged particles emanating from the specimen due to the scanning operation are detected by means of a charged particle detector provided between the specimen and the objective lens.
In another configuration of the present invention, an electron beam generated by an electron source is converged so as to generate a crossover and the electron beam is converged on a specimen by means of an objective lens provided between the crossover and the specimen; the specimen is scanned by using the electron beam; and charged particles emanating from the specimen due to the scanning operation are detected by means of a charged particle detector provided between the specimen and the objective lens.
In still another configuration of the present invention, an electron beam generated by an electron source is converged so as to generate a crossover while the electron beam is being converged on a specimen by means of an objective lens provided between the crossover and the specimen; the specimen is scanned by using the electron beam while the specimen is being moved continuously; and charged particles emanating from the specimen due to the scanning operation are detected by means of a charged particle detector provided between the specimen and the objective lens.
Then, charged particles detected by the charged particle detector are converted into an electrical signal conveying picture information and pictures are compared with each other on the basis of the picture information in order to detect a defect.
The comparison of pictures to detect a defect as described above includes comparison of a picture of an area on a specimen with a picture of another area on the same specimen and comparison of a picture of a an area on a specimen with a reference picture provided in advance.
According to a preferred embodiment of the present invention, a voltage for decelerating an electron beam is applied to a specimen. The voltage works as an acceleration voltage for charged particles emanating from the specimen, causing the charged particles to tend to form parallel beams.
According to another preferred embodiment of the present invention, charged particles emanating from the specimen are deflected by a deflection electric field and a deflection magnetic field which are substantially orthogonal to each other in the same direction. The amount of deflection of an electron beam radiated to a specimen by the deflection electric field and the amount of deflection of the electron beam by the deflection magnetic field are substantially equal to each other in magnitude but have mutually opposite directions so that one of the deflections cancels the other. As a result, a disturbance to deflection of an electron beam, that is radiated to the specimen, caused by the deflection electric field and the deflection magnetic field does not substantially exist.
According to still another preferred embodiment of the present invention, since charged particles are detected without passing through an objective lens, unlike the TTL system, even if a retarding voltage is reduced, the efficiency of detection of secondary electrons does not decrease and, in addition, the rotation of a picture can be made small.
According to a further preferred embodiment of the present invention, secondary electrons of charged particles emanating from a specimen are radiated to a conductive secondary-electron generating substance for further generating secondary electrons to be detected by a charged particle detector.
According to a still further preferred embodiment of the present invention, an electron beam is put in a blanked state with a crossover of the electron beam serving as a fulcrum. If the electron beam is parallel beams with no crossover, the position of radiation of the blanked electron beam on a specimen changes, giving rise to a problem that an area adjacent to a radiation area is electrically charged inadvertently. In the case of this embodiment, however, since the electron beam is put in a blanked state with a crossover thereof serving as a fulcrum, the position of radiation of the electron beam on the specimen does not change, allowing the problem to be solved.
BRIEF DESCRIPTION OF THE DRAWINGS
An embodiment of the present invention will be described by referring to the following diagrams wherein:
FIG. 1 is a longitudinal sectional view showing the configuration of an inspection system using an electron beam as implemented by an embodiment of the present invention in a simple and plain manner;
FIG. 2 is a block diagram showing a flow of a general process of fabricating a semiconductor device;
FIGS. 3( a ) and 3 ( b ) are diagrams each showing an example of a picture obtained as a result of observation of a circuit pattern on a semiconductor wafer by means of an SEM in a process of fabrication of a semiconductor device;
FIG. 4 is a flowchart showing a procedure for inspecting a circuit pattern created on a semiconductor wafer;
FIG. 5 is a diagram showing a plan view of a wafer seen from a position above the wafer;
FIG. 6 is an enlarged diagram showing a portion of the wafer shown in FIG. 5 ;
FIGS. 7( a ) and 7 ( b ) are conceptual diagrams showing a blanked state of an electron beam;
FIG. 8 is an enlarged diagram similar to FIG. 6 showing a portion of the wafer shown in FIG. 5 ;
FIGS. 9( a ) to 9 ( c ) are diagrams showing pictures to be compared with each other and a result of the comparison;
FIG. 10 is a diagram showing a relation between the picture acquisition time per cm 2 and the measurement time per pixel;
FIG. 11 is a diagram showing a relation between the picture acquisition time per cm 2 and the current of an electron beam;
FIG. 12 is a diagram showing a relation between the diameter of an electron beam and the acceleration voltage; and
FIG. 13 is a diagram showing relations between the efficiency of detection of secondary electrons and the retarding voltage.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention will become more apparent from a careful study of the following detailed description of a preferred embodiment with reference to the accompanying diagrams.
FIG. 2 is a block diagram showing a flow of a general process of fabricating a semiconductor device. As is obvious from the figure, in a process of fabricating semiconductor devices, steps 51 to 55 are repeated to create a number of patterns of semiconductor devices on wafers. Each of the steps to create a pattern comprises roughly a film creation step 56 , a resist coating step 57 , an exposure step 58 , a development step 59 , an etching step 60 , a resist removing step 61 and a cleaning step 62 . A circuit pattern will not be created normally on the wafer unless fabrication conditions are optimized at each of the steps.
External inspection steps 63 and 64 to inspect a circuit pattern are provided between the steps described above. When a defect is detected as a result of the inspections carried out at the steps 63 and 64 , the result of the inspections is reflected in a step in the process which has generated the defect so that generation of similar defects can be suppressed. The result of the inspection is reflected typically by letting a defect control system 65 shown in FIG. 2 transmit data to pieces of fabrication equipment of the steps 56 , 57 , 58 and 59 of the process where fabrication conditions are changed automatically in accordance with the data.
FIGS. 3( a ) and 3 ( b ) are diagrams each showing an example of a picture 70 obtained as a result of observation of a circuit pattern on a semiconductor wafer by means of a scanning electron microscope (SEM) in a process of fabrication of a semiconductor device. To be more specific, FIG. 3( a ) is a diagram showing a circuit pattern obtained as a normal result of a fabrication process and FIG. 3( b ) is a diagram showing a circuit pattern with a fabrication defect. For example, when an abnormality is resulted in at the film creation step 56 shown in FIG. 2 , particles are stuck to the surface of a semiconductor wafer, becoming an isolated defect A on the picture shown in FIG. 3( b ). In addition, when fabrication conditions such as the focus and the exposure time at the exposure step 58 following the resist coating step 57 are not optimum, there will be generated spots at which the intensity and quantity of light radiated to the resist are either excessive or insufficient, resulting in a short C, a disconnection E, a thinning or an omission D on the picture shown in FIG. 3( b ). If a defect results on a reticule or a mask at the exposure step 58 , a shape abnormality of the pattern will be prone to generation.
In addition, if the amount of etching is not optimized or if a thin film or particles are generated at the etching step 60 , a bad aperture G is also generated besides the short C, a protrusion B and the isolated defect A. At the cleaning step 62 , abnormal oxidation is apt to occur at places like a pattern corner due to draining conditions during a drying process, resulting in a thin film residual F which is difficult to observe by means of an optical microscope.
Thus, in a wafer fabrication process, it is necessary to optimize fabrication conditions so that these kinds of defect are not generated and to early detect a generated abnormality and to feed back information on the defect to a step at which the abnormality has been generated.
As described above, in order to detect a defect like the one described above, external inspections 63 and 64 are typically carried out after the development step 59 and the resist removing step 61 respectively as shown in FIG. 2 . In these external inspections, an inspection apparatus of the present invention using an electron beam is used.
FIG. 1 is a longitudinal sectional view showing the configuration of an inspection system using an electron beam as implemented by the embodiment of the present invention in a simple and plain manner.
In the inspection system shown in FIG. 1 , an electron gun 1 comprises an electron source 2 , a drawing electrode 3 and an acceleration electrode 4 . A drawing voltage V 1 is generated between the electron source 2 and the drawing electrode 3 by a drawing power supply 5 to draw an electron beam 36 from the electron source 2 . The acceleration electrode 4 is sustained at the earth electric potential. An acceleration voltage Vacc is generated between the acceleration electrode 4 and the electron source 2 by an acceleration power source 6 to accelerate the electron beam 36 .
The accelerated electron beam 36 is converged by a first convergence lens 8 so as to generate a crossover 10 between the first convergence lens 8 and an objective lens 9 which serves as a second convergence lens. The first and second convergence lenses 8 and 9 are connected to a lens power supply 7 . The electron beam 36 is further converged by the objective lens 9 on a specimen 13 such as a semiconductor wafer placed on a specimen stage 12 which can be moved horizontally by a stage driving unit not shown in the figure and a length measuring unit 11 for position monitoring use. That is to say, the converged electron beam 36 is radiated to the specimen 13 . The configuration described above is accommodated in a container 43 which sustains a vacuum environment appropriate for radiation of the electron beam 36 .
A negative voltage is applied to the specimen 13 as a retarding voltage for decelerating the electron beam 36 by a variable deceleration power supply 14 . A voltage is further applied by an electrode 34 in the positive direction to the specimen 13 . The electrode 34 is provided between the specimen 13 and the objective lens 9 . Thus, the electron beam 36 is decelerated by the retarding voltage. Normally, the electrode 34 is set at the earth electric potential and the retarding voltage can be changed arbitrarily by adjusting the variable deceleration power supply 14 .
A diaphragm 15 is provided between the first convergence lens 8 and the crossover 10 whereas a diaphragm 41 is provided between the crossover 10 and an electron beam scanning deflector 16 . The diaphragms 15 and 41 shield excessive electrons and are also useful for determination of an angular aperture of the electron beam 36 .
Provided between the crossover 10 and the objective lens 9 , the electron beam scanning deflector 16 has a function to deflect the converged electron beam 36 so as to let the electron beam 36 scan the specimen 13 . The electron beam scanning deflector 16 is provided inside the objective lens 9 at such a position that a fulcrum of the deflection thereof substantially coincides with the center of a magnetic pole gap of the objective lens 9 . As a result, the amount of deflection distortion can be reduced.
Provided between the diaphragm 15 and the electron beam scanning deflector 16 , a blanking deflector 17 is used for deflecting and blanking the electron beam 36 at a position where the crossover 10 is created. The blanking deflector 17 is connected to a scanning-signal generating unit 24 .
FIG. 4 is a flowchart showing a procedure for inspecting a circuit pattern created on a semiconductor wafer by using an inspection system provided by the present invention.
First of all, the specimen 13 is mounted on the specimen stage 12 and, then, the specimen stage 12 is moved to the inside of the container 41 . Subsequently, air is exhausted from a specimen inspection chamber inside the container 41 to put the chamber in a vacuum state and a retarding voltage is applied to the specimen 13 .
When the specimen 13 is scanned by using the converged electron beam 36 , reflected electrons and secondary electrons 33 , charged particles, emanate from the specimen 13 . The secondary electrons 33 are defined as electrons each having an energy of 50 eV or smaller.
Since positive and negative directions of the secondary electrons 33 are just opposite to those of the electron beam 36 radiated to the specimen 13 , the retarding voltage generated to decelerate the electron beam 36 works as an acceleration voltage for the secondary electrons 33 . Thus, since the secondary electrons 33 are accelerated by the retarding voltage, the directions of the secondary electrons are uniform. As a result, the secondary electrons 33 form substantially parallel beams entering an E×B (E Cross B) deflector 18 which is provided between the specimen 13 and the objective lens 9 .
Provided with a deflection electric-field generator for generating a deflection electric field for deflecting the secondary electrons 33 , the E×B deflector 18 also includes a deflection magnetic-field generator for generating a deflection magnetic field for canceling the deflection of the electron beam 36 radiated to the specimen 13 by the deflection electric field. The deflection magnetic field is generated in a direction perpendicular to the direction of the deflection electric field. Therefore, the deflection electric field works to deflect the secondary electrons 33 in almost the same direction as the deflection magnetic field. Thus, the deflection electric field and the deflection magnetic field generated by the E×B deflector 18 deflect the accelerated secondary electrons 33 without having a bad effect on the electron beam 36 radiated to the specimen 13 because of the mutual cancellation.
In order to sustain each of the deflection angles at a substantially fixed value, the deflection electric field and the deflection magnetic field generated by the E×B deflector 18 can be changed in a way interlocked with a variation in retarding voltage. Used for generating a deflection electric field and a deflection magnetic field, the E×B deflector 18 is also referred to as a deflection electric-field/deflection magnetic-field generator in some cases.
The secondary electrons 33 deflected by the deflection electric field and the deflection magnetic field generated by the E×B deflector 18 are radiated to a secondary-electron generating substance 19 , colliding with the secondary-electron generating substance 19 . The secondary-electron generating substance 19 is provided between the objective lens 9 and the E×B deflector 18 around the axis of the electron beam 36 . The secondary-electron generating substance 19 has a shape resembling a cone with the lateral cross-sectional area thereof increasing along the axis in the direction toward the electron gun 1 . The secondary-electron generating substance 19 is made of CuBeO and has a capability of generating second secondary electrons 20 five times the hitting secondary electrons in number. The second secondary electrons 20 emanating from the secondary-electron generating substance 19 which each have an energy of 50 eV or smaller are detected by a charged particle detector 21 , being converted into an electrical signal.
The height of the specimen 13 is measured by an optical specimen-height measurement unit 22 in a real-time manner and the measured height is fed back to the lens power supply 7 through a correction control circuit 23 for correcting the focal distance of the objective lens 9 dynamically. In addition, the position of radiation of the electron beam 36 on the specimen 13 is detected by a length measurement unit 11 for position monitoring and the detected radiation position is fed back to a scanning-signal generation unit 24 through the correction control circuit 23 for controlling the position of radiation of the electron beam 36 on the specimen 13 .
FIG. 5 is a diagram showing a plan view of a semiconductor wafer 44 , an example of the specimen 13 , as seen from a position above the wafer 44 and FIG. 6 is an enlarged diagram showing a portion of the wafer 44 shown in FIG. 5 . The wafer 44 is continuously moved by a stage driving unit not shown in the figure in the y direction of x-y coordinates as indicated by an arrow y. On the other hand, an operation to scan the wafer 44 by using the electron beam 36 is carried out in the x direction indicated by an arrow x. The scanning operation comprises actual scanning sweeps and a blanked-state sweeps in the x direction which are repeated alternately.
In order to radiate the electron beam 36 to correct positions on the wafer 44 with correct timing, during a fly-back period of the scanning operation, that is, during a blanked-state sweep, the electron beam 36 is deflected and blanked by means of the blanking deflector 17 shown in FIG. 1 so that the electron beam 36 is not directed toward the wafer 44 .
An operation to scan the wafer 44 by using the electron beam 36 is started at a point A shown in FIG. 5 and carried out till a point B. While the scanning operation is being carried out, the wafer 44 is moved along with the specimen stage 12 in the y direction. Then, between the point B and a point A′, the electron beam 36 is put in a blanked state as shown by a dashed line prior to resumption of the scanning from the point A′ to a point B′. For more information refer to FIG. 6 . While repeating the actual scanning and blanked-state sweeps alternately in this way, a scanning operation is continued to a line between points C and D.
After the scanning operation from the point A to the point C on the wafer 44 has been completed, the wafer 44 is moved to the left in the x direction by a distance equal to the scanning width w, shifting the position of radiation from the point C to a point D. Then, the scanning operation by using the electron beam 36 from the point A to the point C is repeated now from the point D to the point B by repeating the actual scanning and blanked-state sweeps alternately while the wafer 44 is being moved this time in the y direction. After the scanning operation from the point D to the point B on the wafer 44 has been completed, the wafer 44 is moved to the left in the x direction by a distance equal to the scanning width w, shifting the position of radiation from the point B to a point F.
By repeating the scanning operations from the point A to the point F described above, the entire surface of the wafer 44 is scanned by using the electron beam 36 .
FIGS. 7( a ) and 7 ( b ) are conceptual diagrams showing a blanked state of the electron beam 36 shown in FIG. 1 .
In the present embodiment, the electron beam 36 shown in FIG. 1 is put in a blanked state with the crossover 10 of the electron beam 36 taken as a fulcrum as shown in FIG. 7( a ). If the electron beam 36 is deflected with a point other than the crossover 10 taken as a fulcrum in order to put the electron beam 36 in a blanked state, the position of radiation of the electron beam 36 on the wafer 44 is inadvertently shifted during the deflection. FIG. 7( b ) is a diagram showing a case in which the electron beam 36 is parallel beams. In this case, when the electron beam 36 is put in a blanked state, there results in a beam that can not be shielded by the diaphragm 41 during the blanking operation. Such a beam is inadvertently radiated to a small adjacent region which is not supposed to be exposed to the beam. As a result, during the blanking operation, an area naturally not supposed to experience radiation by the electron beam 36 is inadvertently exposed to the electron beam 36 to result in a wrong picture. In order to solve this problem, in the embodiment of the present invention, the electron beam 36 is deflected with the crossover 10 taken as a fulcrum during a blanking operation. As a result, the position of radiation of the electron beam 36 on the wafer 44 can be prevented from being shifted, making it possible to avoid an incorrect resulting picture.
The scanning operation of the specimen 13 or the wafer 44 by using the electron beam 36 is carried out by deflecting the electron beam 36 in the x direction while continuously moving the specimen 13 or the wafer 44 in the y direction. Instead of repeating actual scanning and blanked-state sweeps alternately as described above, consecutive actual scanning sweeps can be carried out back and forth. In this case, the sweeping speed in an onward deflection is set at a value equal to the sweeping speed in a retreat deflection. In such a scheme, the blanking deflector 17 can be eliminated and the scanning time can be shortened by periods required to blank the electron beam 36 . In this case, however, care must be exercised as follows.
FIG. 8 is an enlarged diagram similar to FIG. 6 showing scanning directions of the electron beam 36 on a portion of the wafer 44 shown in FIG. 5 . The end and start points B and B′ of a back-and-forth deflection of the electron beam 36 on the wafer 44 are exposed to the focused electron beam 36 radiated thereto during a short period of time. To put it in detail, at the end point B of a scanning sweep in the x direction from the left to the right, the movement of the electron beam 36 in the x direction is halted to wait for the position of radiation to be shifted to the start point B′ by a movement of the wafer 44 in the y direction by a distance equal to the scanning width. After the position of radiation has been shifted to the start point B′, the position of radiation is moved from the right to the left in the x direction. During the period of time to wait for the position of radiation to be shifted in the y direction to the start point B′, the radiation of the electron beam 36 is continued in the y direction along a distance on the wafer 44 from an area centering at the end point B to an area centering at the start point B′. For this reason, in the case of a specimen 13 exhibiting an electrically charging phenomenon with an extremely short time constant, the brightness of a picture taken from these areas will not be uniform. In order to make the amount of radiation provided by the electron beam 36 substantially uniform over the entire surface of the wafer 44 , the scanning speed of the electron beam 36 is controlled so that the speed along a line between the points B and B′ is set at a value higher than the speed along a line between the points A and B shown in FIG. 8 .
Next, picture processing carried out by a picture processing unit 42 shown in FIG. 1 is explained.
The picture processing unit 42 detects a defect on the specimen 13 from an electrical signal supplied by the charged particle detector 21 by way of an amplifier 25 and an A/D converter 26 . To put it in detail, the picture processing unit 42 detects the number of second secondary electrons and converts the number of second secondary electrons into an electrical signal which is amplified by the amplifier 25 before being converted by the A/D converter 26 into digital data. The digital data is stored in storage units 27 and 28 employed in the picture processing unit 42 as a picture signal. To put it concretely, first of all, a picture signal representing the number of second secondary electrons corresponding to a first inspection area on the wafer 44 is stored in the storage unit 27 .
Then, a picture signal representing the number of second secondary electrons corresponding to a second inspection area on the wafer 44 adjacent to the first inspection area with the same circuit pattern is stored in the storage unit 28 while, at the same time, the picture signal for the second inspection area is being compared with the picture signal for the first inspection area. Subsequently, a picture signal representing the number of second secondary electrons corresponding to a third inspection area on the wafer 44 is stored in the storage unit 27 while, at the same time, the picture signal for the third inspection area is being compared with the picture signal for the second inspection area stored in the storage unit 28 . These operations are repeated to store and compare picture signals for all inspection areas on the wafer 44 . It should be noted that a picture signal stored in the storage unit 28 is displayed on a monitor 32 .
A picture signal is compared with another picture signal by a processing unit 29 and a defect judgment unit 30 shown in FIG. 1 . The processing unit 29 computes a variety of statistics such as averages of picture concentration values, variances and differences among peripheral pixels for secondary-electron picture signals stored in the storage units 27 and 28 on the basis of defect judgment conditions already found. Picture signals completing the processing carried out by the processing unit 29 are supplied to the defect judgment unit 30 to be compared with each other to extract a difference signal. The defect judgment conditions found and stored in memory before are referred to in order to split the difference signal into a defect signal and a signal other than the defect signal.
FIGS. 9( a ) to 9 ( c ) are diagrams showing pictures 70 to be compared with each other in an example of comparison and a result of the comparison. To be more specific, FIG. 9( a ) shows a secondary-electron picture signal stored in the storage unit 27 and FIG. 9( b ) shows a secondary-electron picture signal stored in the storage unit 28 . If picture 1 shown in FIG. 9( a ) is subtracted from picture 2 shown in FIG. 9( b ), a difference picture representing a defect shown in FIG. 9( c ) is obtained.
As an alternative, a picture signal representing the number of second secondary electrons corresponding to an inspection area of a circuit pattern used as a standard is stored in the storage unit 27 and, then, a picture signal representing the number of second secondary electrons corresponding to an inspection area of a circuit pattern on the specimen 13 is stored in the storage unit 28 while, at the same time, the picture signal for the inspection area on the specimen 13 is being compared with the picture signal for the standard circuit pattern stored in the storage unit 27 . To put in detail, first of all, an inspection area and a desired inspection condition for a good semiconductor device are input from a control unit 31 and the inspection area of the good semiconductor device is then inspected under the inspection condition. Then, a secondary-electron picture signal for the desired inspection area is fetched and stored in the storage unit 27 . Subsequently, the specimen 13 serving as an inspection target is inspected in the same way as the good semiconductor device and a secondary-electron picture signal for the specimen 13 is fetched and stored in the storage unit 28 . At the same time, the secondary-electron picture for the specimen 13 is compared with the secondary-electron picture of the good semiconductor device stored in the storage unit 27 after the position of the former is adjusted to the latter to detect a defect.
As the good semiconductor device used in the above alternative method, a good portion of the specimen 13 , or a good wafer or a good chip other than the specimen 13 can be used. In the specimen 13 , for example, a defect may be generated due to a shift generated in adjustment of a lower-layer pattern and an upper-layer pattern in creation of a circuit pattern. If a circuit pattern is compared with another circuit pattern on the same wafer or the same chip, defects generated uniformly over the entire wafer like the defect described above are overlooked. If the picture signal for the specimen 13 is compared with a picture signal for a good device stored in advance, on the other hand, the defects generated uniformly over the entire wafer can also be detected.
The control unit 31 shown in FIG. 1 issues an operation instruction to components of the inspection system and sets conditions for the components. Thus, a variety of conditions including information on an acceleration voltage, a deflection width (or a scanning width) and a deflection speed (or a scanning speed) of the electron beam, a movement speed of the specimen stage and timing to fetch a signal output by the detector are supplied to the control unit 31 in advance.
The following is a description of differences between the inspection system using an electron beam according to the present invention and the conventional scanning electron microscope referred to hereafter simply as an SEM. In the following description, the inspection system using an electron beam according to the present invention is referred to hereafter simply as the present inspection system for the sake of convenience.
An SEM is an apparatus used for observing a very limited area, for example, an area of several tens of square μm at a high magnification over a relatively long period of observation time. Even with a length measurement scanning electron microscope referred to hereafter simply as a length measurement SEM, one of semiconductor inspection apparatuses, the user is capable of doing no more than observation and measurement of only a limited plurality of points on a wafer. On the other hand, the present inspection apparatus is equipment for searching a specimen such as a wafer for a location on the specimen at which a defect exists. Thus, since the present inspection apparatus has to inspect an extremely large area in every nook and corner, the fact that the inspection must be carried out at a high speed is an important requirement.
FIG. 10 is a diagram showing a relation between the picture acquisition time per cm 2 and the measurement time per pixel and FIG. 11 is a diagram showing a relation between the picture acquisition time per cm 2 and the current of an electron beam.
In general, an S/N ratio of an electron beam picture has a correlation with the square root of the number of radiated electrons per pixel in an electron beam radiated to a specimen. A defect to be detected from a specimen is such an infinitesimal defect that inspection by pixel comparison is desirable. From the size of a pattern to be inspected, assume that the demanded resolution of the inspection system is set at a value of the order of 0.1 μm. In this case, the pixel size is also about 0.1 μm. From this point of view and experiences gained by the inventors, it is desirable to have a raw picture prior to picture processing with an S/N ratio of at least 10 after detection by a charged particle detector. On the other hand, the length of an inspection time required in inspection of circuit patterns on a wafer is generally about 200 sec/cm 2 . If the length of a time required only for acquisition of a picture is about half the inspection time which is about 100 sec/cm 2 , the measurement time of 1 pixel is equal to or smaller than 10 nsec as shown in FIG. 10 . In this case, since the number of electrons required per pixel is 6,000, it is necessary to set the electron beam current at least 100 nA as shown in FIG. 11 . In the case of an SEM or a length measurement SEM, even a slow picture acquisition time per pixel does not give rise to a problem in the practical use. Thus, an electron beam current of several hundreds of pA or smaller can be used as shown in FIG. 11 .
Taking the things described above into consideration, in the embodiment of the present invention, the current of an electron beam radiated to a specimen, the pixel size, the spot size of the electron beam on the specimen and the continuous movement speed of the specimen stage 12 are set at 100 nA, 0.1 μm, 0.08 μm (a value smaller than the resolution of 0.1 μm) and 10 mm/sec respectively. Under these conditions, a high-speed inspection of 200 sec/cm 2 can be achieved by carrying out a scanning operation by using an electron beam on the same area of the specimen 13 only once instead of carrying out the scanning operation a plurality of times.
In the case of the conventional SEM or the conventional length measurement SEM, the current of an electron beam radiated to a specimen is in the range several pA to several hundreds of pA. Thus, the inspection time per 1 cm 2 would be several hundreds of hours. For this reason, the SEM or the length measurement SEM can not substantially be put to practical use for inspection of the entire surface of a specimen such as a wafer in a fabrication process.
In addition, in the embodiment with the above specifications, in order to generate a large current of the electron beam and to allow inspection to be carried out at a high speed, as the electron source 2 of the electron gun 1 , a thermal electric-field emission electron source of a diffusion supply type, that is, an electron source made of Zr/O/W as a source material, is employed. Furthermore, a measurement time of 10 nsec per pixel corresponds to a 100 MHz sampling frequency of the picture. It is thus necessary to provide a charged particle detector 21 with a high response speed commensurate with the sampling frequency of 100 MHz. As a charged particle detector 21 satisfying this requirement, a PIN type semiconductor detector is employed.
In the case of a specimen exhibiting a characteristic of low conductivity or no conductivity, the specimen is electrically charged by an, electron beam radiated thereto. Since the amount of electrical charge depends on the acceleration voltage of the electron beam, this problem can be solved by reducing the energy of the electrons in the beam. In an electron-beam inspection system based on picture comparison, however, a large current electron beam of 100 nA is used. Thus, if the acceleration voltage is reduced, the amount of aberration caused by a space charge effect, that is, the amount of spreading of the electron beam in the radial direction, increases so that it is difficult to obtain a 0.08-μm spot size of the electron beam on the specimen. As a result, the resolution is deteriorated.
FIG. 12 is a diagram showing a relation between the diameter of an electron beam and the acceleration voltage at an electron beam current of 100 nA and a specimen radiation energy of 0.5 keV. In the embodiment of the present invention, in order to prevent the resolution from deteriorating and changing due to the space charge effect and to obtain a stable 0.08-μm spot size of the electron beam on the specimen, the acceleration voltage is set at a fixed value of 10 kV as shown in FIG. 12 .
The quality of a picture produced by the present inspection system is much affected by the energy of the electron beam radiated to the specimen. This energy is adjusted in accordance with the type of the specimen. When inspecting a specimen which is hardly charged electrically or when putting emphasis on the contrast of a picture in order to know an edge portion of a circuit pattern on a specimen, the amount of energy is increased. In the case of a specimen apt to be charged electrically, on the other hand, the amount of energy is decreased. It is thus necessary to find out and set an optimum radiation energy of the electron beam each time the type of a specimen to be inspected changes.
In the embodiment of the present invention, an optimum radiation energy of the electron beam radiated to a specimen 13 is set by adjusting a negative voltage applied to the specimen 13 , that is, the retarding voltage, instead of changing the acceleration voltage Vacc. The retarding voltage can be changed by adjusting the variable deceleration power supply 14 .
FIG. 13 is a diagram showing relations between the efficiency of detection of secondary electrons expressed in terms of % and the retarding voltage expressed in terms of kV. To be more specific, curve ( 1 ) shown in the figure represents a relation for a long focal distance system adopted by the embodiment of the present invention whereas curve ( 2 ) represents a relation for the TTL system adopted by the conventional inspection system. As described before, the retarding voltage should be changed in dependence on the type of the specimen and the retarding voltage exhibits an effect to accelerate secondary electrons. In the case of the TTL system, the efficiency of detection of secondary electrons varies considerably when the retarding voltage is changed as shown in FIG. 12 . In the case of the embodiment of the present invention, on the other hand, the efficiency of detection of secondary electrons does not vary considerably even if the retarding voltage is changed. This is because, in the case of the TTL system, secondary electrons emanating from a specimen pass through a magnetic field of the objective lens to be converged thereby and the position of convergence in the axial direction changes with a variation in retarding voltage. The displacement of the position of convergence is the main cause of the big change in secondary-electron detection efficiency. In the case of the embodiment of the present invention, on the other hand, since secondary electrons 33 do not pass through the magnetic field of the objective lens 9 , a change in retarding voltage does not have a big effect on the efficiency of detection of secondary electrons 33 . In this embodiment, since the rotation of a picture is small and variations in secondary-electron detection efficiency are also small, stabilization of an inspected picture is brought about as a result.
As described before, secondary electrons 33 emanating from a specimen 13 will spread if they are left as they are. Since a retarding voltage accelerates the secondary electrons 33 , putting them into substantially parallel beams, however, the efficiency of convergence of the secondary electrons 33 is improved. The secondary electrons 33 are then deflected by means of a defection electric field and a deflection magnetic field generated by the E×B deflector 18 by an angle of typically 5 degrees with respect to the center axis of the electron beam 36 , hitting the secondary-electron generating substance 19 . The collision of the secondary electrons 33 with the secondary-electron generating substance 19 further generates a large number of second secondary electrons 20 . As a result, the efficiency of detection of secondary electrons is improved considerably by virtue of the parallel beams and the collision of the secondary electrons 33 with the secondary-electron generating substance 19 .
In an apparatus such as the conventional SEM, charged particles emanating from a specimen 13 are detected after passing through the objective lens 9 . As described above, this system is referred to as a TTL (through the lens) system. According to the TTL system, by operating the objective lens at a short focal distance, the amount of aberration of the electron beam can be reduced, hence, allowing the resolution to be increased. In the case of the embodiment of the present invention, on the other hand, charged particles 33 emanating from a specimen 13 are detected by the objective lens 9 as shown In FIG. 1 . For this reason, the focal distance of the objective lens 9 is set at a large value in comparison with the TTL system. To be more specific, in the case of the conventional TTL system, the focal distance of the objective lens is set at a value of the order of 5 mm. In the case of the embodiment of the present invention, on the other hand, the focal distance is set at a value of about 40 mm. In addition, in order to reduce the amount of aberration of the electron beam, a high acceleration voltage of 10 kV is used as described earlier.
As a result, according to the embodiment of the present invention, the deflection width of the electron beam 36 radiated for acquisition of a picture of a specimen 13 , that is the width of scanning by using the electron beam 36 , can be set at a large value. In the case of the conventional TTL, for example, the deflection width of the electron beam is set at a value of the order of 100 μm. In the case of the embodiment of the present invention, on the other hand, the deflection width can be set at a value of about 500 μm.
Since the surface of a specimen 13 is not a perfectly plane surface, the height of the specimen 13 changes when the position of radiation an area on the specimen 13 to be inspected is moved. It is thus necessary to operate the objective lens 9 by always adjusting the focal distance to the surface of the specimen 13 through variation of excitation of the objective lens 9 . In the conventional TTL system, the objective lens is operated at a short focal distance by strong excitation. With a strongly excited objective lens, however, the flow of the electron beam exhibits a rotation in the horizontal direction accompanying a change in specimen height. As a result, since the resulting picture also rotates, it is necessary to compensate the picture for the rotation. In the case of the embodiment of the present invention, on the other hand, the objective lens 9 is operated at a long focal distance by weak excitation. Typically, the objective lens 9 is excited at IN/(E)=9 where the symbol I is the current of the objective lens expressed in terms of amperes, the symbol N is the number of turns of a coil employed in the objective lens 9 and the symbol E is the energy of the electron beam expressed in terms of eV. As a result, even if the focal distance is adjusted little to accompany a change in height of the specimen 13 , the rotation of the electron beam 36 and, hence, the rotation of the resulting picture are so small that they can be ignored, making it unnecessary to compensate the picture for the rotation.
In the embodiment of the present invention described above, secondary electrons 33 emanating from a specimen 13 are used for creating a picture. It should be noted that a picture can also be created by using electrons reflected by the specimen 13 due to radiation of the electron beam 36 thereto and scattered on the rear side of the specimen 13 to give yet the same effect. | Problems encountered in the conventional inspection method and the conventional apparatus adopting the method are solved by the present invention using an electron beam by providing a novel inspection method and an inspection apparatus adopting the novel method which are capable of increasing the speed to scan a specimen such as a semiconductor wafer.
The inspection novel method provided by the present invention comprises the steps of: generating an electron beam; converging the generated electron beam on a specimen by using an objective lens; scanning the specimen by using the converged electron beam; continuously moving the specimen during scanning; detecting charged particles emanating from the specimen at a location between the specimen and the objective lens and converting the detected charged particles into an electrical signal; storing picture information conveyed by the electrical signal; comparing a picture with another by using the stored picture information; and detecting a defect of the specimen. | 7 |
FIELD AND BACKGROUND OF THE INVENTION
This invention relates in general to sewing machines and in particular to a new and useful sewing machine and method for approaching a predetermined end point of a sewn seam which is spaced from an edge of the workpiece.
In an older arrangement disclosed in German patent No. 31 50 141 the shortening of the length of the last stitch before the end is achieved in that the forward movement of the feeder is interrupted by the abrupt lowering thereof when the needle has reached the desired end point of the seam. This measure however, cannot be applied to a sewing machine with needle transport in a simple manner because during forward movement the needle is in the workpiece and its movement would have to be interrupted also. But this involves additional difficulties and considerable expense.
There is an older proposal disclosed in German patent application P No. 33 24 715.3 for the execution of one or more stitches with a shortened stitch length before an end point with the aid of a sewing machine with needle transport. Here the setting gearing for adjustment of the feed length of the cloth feeder and of the needle is readjusted just before execution of the last stitch or stitches in such a way that the cloth feeder and needle also execute only the residual stitch length required in each instance for approaching the end point of the seam.
The invention provides a sewing machine which achieves the approach of the end point without shortening the movement of the feed elements in a forward direction. Thereby an additional novel method for approaching the exact end position in sewing machines with needle transport is now indicated.
In accordance with the method of the invention, the end point of a seam which is spaced from an edge of the workpiece is arrived at with the sewing machine which comprises an adjustable needle and a lower transport body sensing the action of the needle and triggering the process for positioning the needle in the end point during the passage through the edge. In accordance with the invention a pulse generator is coupled with the main shaft of the sewing machine so as to deliver counting pulses for a pulse counter and these are transmitted to a micro-computer which controls the action of the feed as a function of the pulses originating from the sensor and from the pulse generator. With the invention, a desired shortening of the length of one or more of the last stitches before the end point of the seam is effected by moving the workpiece back by a difference between the desired stitch length and the stitch length set by the setting device which controls the feed before the execution of the adjustment of the feed. For correction of the stitch length which is carried out during the feed phase the cloth feeder is connected with a switching gear which is controlled by the micro-computer and effects a controlled switching on of the feed in a reverse feeding phase which precedes the respective forward feeding phase. To obtain a stitch length shortened relative to the set stitch length, the lower feed means for feeding the material is connected with a switching gear which operates the feed under the control of the micro-computer during its reverse feeding phase preceding the respective forward phase. A switching gear advantageously comprises an articulated link transmission which is connected at one end with a crank and with a lift drive for the feeder at the other end by means of a lever arm which is mounted within the housing of the sewing machine. With the device and with a method of the invention, it is possible to utilize the backward movement of the cloth feeding mechanism for the correction of the stitch length executed during the forward movement. By using the articulated link transmission of the invention, a sufficiently rigid connection between the lift drive and the cloth feeder is effected for normal sewing.
One link of the articulated link transmission is held in a stretch position by a spring to effect the outward flexing thereof along with a nose member which projects into the path of a control member. This ensures an exact lifting of the lower cloth feeder in its normally inactive phase with the simultaneous outward pivoting of the articulated link transmission.
Accordingly, it is an object of the invention to provide an improved method for approaching a predeterminable end point of a seam which is being sewn.
A further object of the invention is to provide a sewing machine having means for effecting the precise sewing of a seam along an edge point and which is simple in design, rugged in construction and economical to manufacture.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.
BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a perspective view of the driving mechanism of a sewing machine with lower and needle transport constructed in accordance with the invention;
FIG. 2 is a section taken along the line II--II of FIG. 1, on a larger scale;
FIG. 3 is the schematic perspective representation of various organs of the control required for approaching a predetermined end point of a seam, with its reciprocal connection; and
FIG. 4 is a schematic representation of a corner sewing process.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings, in particular the invention embodied therein comprises a sewing machine which includes a main shaft 2 for driving a needle 5 which is mounted for vertical reciprocation and for back and forth swinging movement. A material feed 9 in the form of a feeding dog is positioned adjacent the needle and is movable to move the workpiece or material W relative to the needle. A sensor 86 is arranged before the needle 5 and triggers the drive for positioning the needle in the end point. The apparatus includes a pulse counter which is connected to a pulse generator 77 and 78 and operated by the main shaft for generating pulses which are delivered to the micro-computer 81. Variable drive means are connected to the feed 9 and the main shaft 2 so as to move the feed in a selected direction and at a selected feed movement. The feed mechanism is also controlled by a setting device 49 for effecting the desired feed motion.
As FIG. 1 shows, a main shaft 2, mounted in a merely indicating housing 1 of the sewing machine, drives via a crank 3 and a link 4 a needle bar 6 equipped with a needle 5. The needle bar is mounted in a rocker 8 swinging in a pivot 7.
Cooperating with the needle 5 is a shuttle (not shown) as well as a workpiece or a cloth feeder 9, which is fastened on a support 11 mounted below the stitch plate 10 of the sewing machine illustrated in FIG. 4.
The support 11 is connected with a forked crank 13, which is fastened on a rocking shaft 14 mounted in the housing 1. To drive the rocking shaft 14, an eccentric 16 whose eccentric rod 17 is articulated to a journal 18 is fastened on a shaft 15 in drive connection with the main shaft 2 in a ratio 1:1. On the journal 18 is mounted a link 19 which by means of a journal 20 is connected with a crank 21 fastened on the rocking shaft 14. Laterally of the eccentric rod 17, there is fastened on journal 18 a link 22 which embraces a journal 24 carried by a crank 23. The effective length of link 19 equals the effective length of link 22, so that, when the two journals 20 and 24 are aligned with one another, the rocking shaft 14 remains at rest despite the moving eccentric rod 17. To vary the movement of the eccentric rod 17 acting on rocking shaft 14, crank 23 is clamped fast on a positioning shaft 25. The parts 14 and 16 to 25 form a positioning gearing 26 for the feed amount and direction of the cloth feeder 9. The positioning shaft 25 carries a crank 27, which is connected via a link 28 with a crank 29 which is fastened on a positioning shaft 30 mounted in the housing 1. The positioning shaft 30 carries a yoke 31, between whose arms 31a an additional yoke 32 is rotatably mounted by means of bolts 33. The arms 32a of yoke 32 are connected by a bolt 34, to which swinging movements about the bolts 33 are imparted by an eccentric 35 fastened on the main shaft 2 via an eccentric rod 36. Arranged on bolt 34 is a further link 37, which by means of a bolt 38 is articulated to a crank 39 which is fastened to one end of a rocking shaft 40 extending parallel to the main shaft 2. With the other rocking shaft 40 a crank 41 is connected which carries a journal 42 which is guided between two flanges 43 arranged on the back of rocker 8. The parts 30 to 40 form positioning gear 44 for the feed amount and direction of the needle 5.
Crank 27 is connected via a tie-rod 45 with one end of a rocking lever 46 which is fastened on a shaft 47 mounted in housing 1. The as yet free end of rocking lever 46 has a spherical projection 46a which protrudes between side walls of a setting groove 48 of a setting device 49 the size of the feed movement of feeder 9 and of the needle 5 is determined, the setting groove 48 being formed as a spiral in such a way that stitch lengths of, for example, 1 to 6 mm can be adjusted on the feeder 9 and the needle 5.
Acting on crank 27 is an extension spring 52 which is hooked by its other end to the housing 1 and which brings it about that the projection 46a of rocker lever 46, projecting into the setting groove 48, is in permanent contact on the outer of the side walls of setting groove 48 and that feeder 9 in conjunction with needle 5 pushes the work forward. For reversal of the feed direction there is fastened on the end of shaft 47 projecting out of housing 1 a switching lever 53 by which rocking lever 46 can be caused to make contact on the inner side wall of setting groove 48.
In axial prolongation of setting shaft 25 there is arranged on housing 1 a potentiometer 54 whose setting member 55 is fastened in an axial bore of setting shaft 25.
The support 11 is connected with a frame 56 which is mounted on a journal 57. The latter is carried by a lever arm 58, which is mounted on a bolt 59 fastened in housing 1.
On shaft 15 is fastened an eccentric 60 whose eccentric rod 61 is connected with a crank 62 which is fastened on a shaft 63 mounted in housing 1. On shaft 63 a second crank 64 is fastened. The latter is connected with one end of link 65 (see also FIG. 2), whose other forked end is connected with a bolt 66. On the latter a second link 67 is mounted, which is carried by the journal 57 and which forms together with link 65 an articulated link gearing 68.
Mounted on journal 57 is a spiral spring 69, which takes support by one end on frame 56 and whose other end acts on link 67. The latter has a stop 67a, which the spiral spring 69 pushes against a cross-web 56a of frame 56. Link 67 is provided with a nose 67b which protrudes into the path of an abutment surface 71a of a control member 71 mounted on bolt 59. Control member 71 has a slot 71b, which serves as guide for a pin 72. The latter is fastened on a holding bracket 73, which is connected with a piston rod 74a of a compressed air cylinder 74.
Shaft 15 carries a pulse disc 76 provided with a plurality of line marks 75 and cooperating with a pulse generator 78 arranged at 180° thereto. Pulse generator 77 (FIG. 3) is connected via a line 79, and pulse generator 78 via a line 80, with a micro-computer 81.
The line marks 75 (FIG. 1) are present on only a part of the pulse disc 76, namely on the part which during the transport phase of feeder 9 and of needle 5 runs through the pulse generator 77. Thus the generator 77 delivers pulses to the micro-computer 81 via line 79 (FIG. 3) only during the transport phase of the sewing machine, while pulse generator 78 delivers pulses to micro-computer 81 only during the nontransport phase.
One input of micro-computer 81 is connected via a line 82 with the potentiometer 54, another via a line 83 with a schematically shown input device 84, and lastly another input via a line 85 with a sensor 86 which is fastened on housing 1 in front of needle 5 above the stitch forming point.
One output of micro-computer 81 is connected via an amplifier not shown and a line 87 with the switching magnet of a 4/2 way valve 88. The multi-way valve 88 serves for the controlled admission of the compressed air cylinder 74, the compressed air source being marked 89. Another output of micro-computer 81 is connected via a line 90 with a known control circuit, (not shown) of a position motor 91, which is in drive connection with shaft 15 via a belt drive 92.
Lastly a counter 93 is connected via a line 94 to one input and via a line 95 to one output of micro-computer 81. Via a line 96 connected to another output of micro-computer 81 the counter 93 is resettable to "0".
The micro-computer 81 processes the pulses coming in from pulse generator 77 and from sensor 86 according to its preset program in a manner known in itself. In addition, it receives the values dependent on the rotational position of potentiometer 54, which simulate the respective adjusted stitch length. Naturally, instead of using the potentiometer 54 for stitch readjustments, the stitch length to be executed can be entered in the microcomputer 81 by hand via the input device 84.
The sensor 86, consisting of a light emitter and light receiver, is fastened to the housing 1 of the sewing machine at the distance L (FIG. 4) before the path of needle 5. Sensor 86 cooperates with a reflection foil 97 glued to the stitch-plate 10 of the sewing machine. A beam of light coming from the light emitter of sensor 86 falls on a scanning point A and is reflected by reflection foil 97 onto the receiver of sensor 86 if there is no workpiece W. As soon as in the cloth transport an edge 98 of the workpiece W, e.g. of a collar, moves over the scanning point A, the workpiece W interrupts the reflection of the beam and sensor 86 sends a switching pulse to micro-computer 81 via line 85 (see also FIG. 3).
During the production of a seam consisting of stitches N at a spacing a from the edge 99 of workpiece W, sensor 86 signals for example that edge 98 of the workpiece has cleared the scanning point A on the stitch-plate 10 of the sewing machine or respectively on the reflection foil 97 glued thereon, by sending a switching pulse to the micro-computer 81 via line 85. Via line 90 the micro-computer switches the position motor 91 to a predetermined low speed, at which the sewing machine can later be stopped when a predetermined end point E is reached.
At the same time, the counter 93, set to "0", is connected by micro-computer 81 via line 95 to line 79 of pulse generator 77. With continued sewing, the pulses delivered by pulse generator 77 then cause upward counting of counter 93 from "0" on.
The switching on of counter 93 occurs in the transport phase of the sewing machine, because the edge 98 of workpiece W passes through the scanning point A only in this phase. In FIG. 4, the position of needle 5 as counter 93 is being switched on is entered. Now counter 93 counts the pulses delivered by pulse generator 77 from delivery of the switching pulses of sensor 86 to completion of the stitch just begun during the residual stitch length Na, and it gives this number of pulses i at the end of this residual stitch to the micro-computer 81. The computer calculates immediately thereafter, from the distance L and the set stitch length n, the number of complete stitches N still to be executed after the residual stitch length N a up to the end point E, and in addition the pulse number for the differences between the stitch length n and the calculated residual length N b for the last shortened stitch.
This computation is dependent on the distance L between needle 5 (FIG. 4) and the scanning point A of sensor 86, on the distance e in the straight prolongation of the seam to be sewn between the end point E and the edge 98 of workpiece W, on the adjusted stitch length n, and lastly on the preset pulse number i during execution of the residual stitch length N a of stitch N just then executed as sensor 86 responds. The distance L is constant. The residual seam length 1 is the distance from the needle 5 to the predetermined end point E.
The pulse number i depends on the pulse generator 77 used. The distance e is dependent on the edge distance a of the seam from the edge 98 or 99 and on the edge angle alpha of the corner of workpiece W.
As the desired stitch length n is being adjusted by the setting device 49 (FIG. 1), the setting shaft 25 is rotated by way of the rocking lever 46, the tie-rod 45, and the crank 27. The resistance of the potentiometer 54 connected with the setting shaft 25 then changes accordingly. This value is entered in the micro-computer 81 via line 82 (FIG. 3).
After execution of the number of complete stitches N as calculated by micro-computer 81, the computer causes the compressed air cylinder 74 to be actuated via the multi-way valve 88 before execution of the residual stitch length N b within the time in which the advance of the workpiece W by the cloth feeder 9 and the needle 5 is just terminated.
The piston 74a of cylinder 74 (FIGS. 1 and 2) pivots the nose 67b of link 67, lifts it, then places itself against the underside of lever arm 58 and pivots the latter by an amount which is determined by the stroke end of the adjustably fastened compressed air cylinder 74. During this process, the articulated link gearing 68 is pivoted out by the pivoting of the nose 67b, thereby abolishing the rigid connection between frame 56 and crank 64. Upon further pivoting of lever arm 58 by the abutment surface 71a, frame 56 is raised and thereby the support 11 with the cloth feeder 9 is pivoted upward. This causes the teeth of the cloth feeder 9 to pass through the stitch-plate 10. At the same time the micro-computer 81 (FIG. 3) sets the counter 93 to the number "0" via line 96, disconnects line 79, and connects line 80.
Now pulse generator 78 sends pulses over line 80 via the microcomputer 81 to the counter 93 until the counter status has reached a pulse number i' which corresponds to the difference between the stitch length n and the calculated residual stitch length N b for the last shortened stitch.
In the above described process, the workpiece W is moved back by feeder 9 by the difference amount between a stitch length n and the residual stitch length N b during backward movement of needle 5 and feeder 9. At counter status i', counter 93 delivers a pulse to micro-computer 81 via line 94, owing to which the micro-computer abruptly disconnects the compressed air cylinder 74 over line 87 via the multi-way valve 88, owing to which the control element 71 is pivoted back into its lower end position.
Under the action of spiral spring 69, the two links 65 and 67 are brought into their stretched position until stop 67a abuts on frame 56, owing to which the latter moves down and lowers the feeder 9 below the stitch-plate 10. After the lowering of feeder 9, the needle 5 and feeder 9 then move back to their starting position by the amount of the residual stitch length N b without entrainment of the workpiece W, whereupon needle 5 plunges into workpiece W exactly by the amount of the residual stitch length N b from the last complete sewing stitch N, the last stitch thus corresponding only to the residual stitch length N b .
Simultaneously with the disconnection of the compressed air cylinder 74 (FIG. 3), the micro-computer 81 gives via line 90 a turn-off command for the position motor 91, which then, after execution of the residual stitch length N b , brings about the stopping of the sewing machine in the low position of needle 5, in a manner known in itself. In this way the seam ends exactly in the predetermined end point E, whereupon the possibility of subsequent rotation of the workpiece W exists.
Even if the disconnect command for the position motor 91 brings about a stopping of the sewing machine with the needle 5 in high position, the conditions for the execution of the residual stitch length N b remain unchanged.
Deviating from the solution described, the predetermined end point E of the seam can be approached also in a different manner. For example, the micro-computer 81 can, after response of sensor 86 in the scanning point A, calculate the pulse number i' which corresponds to the reverse feed of workpiece W by feeder 9 required to reach the end point E, with a period sufficient therefor, in which stitches N of the previous length are being executed. Then, during execution of the remaining stitches, by brief connection of cylinder 74 by micro-computer 81, uniformly shortened stitches can be executed during the reversed feed phase of feeder 9 to the end point E, the number of pulses calculated for the back-transport of workpiece W being distributed over these remaining stitches.
While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles. | A method for approaching a predeterminable end point of a seam spaced from the edge of a workpiece, with a sewing machine which comprises an adjustable needle and lower transport, a sensor arranged before the needle and triggering the process for the positioning of the needle in the end point during passage through the edge, a pulse generator coupled with the main shaft of the sewing machine for the delivery of counting pulses for a pulse counter, and a micro-computer which controls the action of the feed means as a function of the pulses originating from the sensor and from the pulse generator. To execute a desired shortening of the length of one or more of the last stitches before the end point of a seam, the workpiece is moved back by the difference between the desired stitch length and the stitch length set by the setting device, before execution of the adjusted feed. For correction of the stitch length executed during the feed phase, the cloth feeder is connected with a switching gear controlled by the micro-computer for controlled switching on during its reversed feed phase which precedes the respective forward feed phase. | 3 |
FIELD OF THE INVENTION
[0001] This invention relates to a multiplexed capillary electrophoresis (CE) fluorescence detection system and method that may be used for the separation and detection of substances possessing fluorescent properties, e.g., fluorescently labeled dsDNA, amino acids, carbohydrates, fatty acids, proteins, etc.
BACKGROUND OF THE INVENTION
[0002] There are a variety of commercially available instruments applying electrophoresis to analyze DNA samples. One such type is a multi-lane slab gel electrophoresis instrument, which as the name suggests, uses a slab of gel on which DNA samples are placed. Voltage is applied across the gel slab, which induces the migration of the charged DNA sample. The gel acts as a size-based sieving matrix, resulting in the separation of the DNA sample into DNA fragments of different masses.
[0003] Another type of electrophoresis instrument is the capillary electrophoresis (CE) instrument. CE refers to a family of related analytical techniques that use very strong electric fields to separate molecules within narrow-bore capillaries (typically 20-100 μm internal diameter). CE techniques are employed in numerous applications in both industry and academia. Gel- and polymer network-based CE has revolutionized studies of nucleic acids; applications include DNA sequencing, nucleotide quantification, and mutation/polymorphism analysis. By applying electrophoresis in a small diameter fused silica capillary column carrying a buffer solution, the sample size requirement is significantly smaller and the speed of separation and resolution can be increased multiple times compared to the slab gel-electrophoresis method. DNA fragments analyzed by CE are often detected by directing light through the capillary wall, at the components separating from the sample that have been tagged with a fluorescent material, and detecting the fluorescence emissions induced by the incident light. The intensities of the emission are representative of the concentration, amount and/or size of the components of the sample.
[0004] Some of the challenges in designing CE-based instruments and performing CE analysis protocols relate to sample detection techniques. In the case of fluorescence detection, considerable design considerations have been given to, for example, radiation source, optical detection, sensitivity and reliability of the detection, and cost and reliability of the structure of the detection optics.
[0005] The use of CE with fluorescence detection provides high detection sensitivity for DNA analysis. Fluorescence detection is often the detection method of choice in the fields of genomics and proteomics because of its outstanding sensitivity compared to other detection methods.
[0006] Most multiplexed CE systems, whereby multiple capillaries or channels were used to perform separations in parallel, use a laser (coherence light source) as the excitation light source for fluorescence detection (see U.S. Pat. No. 5,582,705). One patent (U.S. Pat. No. 6,828,567) shows a system comprising a light-emitted-diode (LED) associated with each separation channel. Other publications deal with single column detection rather than multiples.
[0007] The use of lasers, or a single light-emitting-diode associated with each channel and/or capillary provides complexity to the instrument and an associated increased expense. In the past, it has been thought the use of a single LED for an array of channels and/or capillaries could not be accomplished because a single LED would provide insufficient output and would not be of a high enough power to illuminate the detection windows of an entire array of capillaries and/or channels at once.
[0008] Fluorescence detection in capillary electrophoresis (CE) provides outstanding sensitivity compared to standard UV absorption detection. The signals of fluorescence detectors are related to the exciting sample volume and the output power at a specific wavelength of the light source. CE uses narrow-bore capillaries (typically 20-100 μm internal diameter) resulting in nL sample volumes to be detected. Therefore, the output power of light sources is critical to obtain a low limit of detection (LOD) and in order to excite most sample molecules high output light sources are often used. The fluorescence excitation light sources can be a gas discharge lamp (mercury or xenon), a laser (gas, solid state, dye, or semiconductor) or a light-emitting-diode (LED). When a gas discharge lamp was used as the fluorescence excitation source the LOD was only 10 times lower than UV absorption detectors. The breakthrough in CE fluorescence detection was due to the introduction of the laser as a light source. The coherent property of the laser makes it easy to focus onto the small detection windows present in CE. A result of this focusing capability and high power output at a specific wavelength is that the optical power density is much higher than that of a conventional lamp at a selected wavelength. Single molecule detection has been demonstrated with CE employing laser-induced fluorescence (LIF) detectors. In regard to multiplexed capillary systems, several fluorescence detection modes have been developed. Most of them used a laser as the light source, including confocal scanning laser induced fluorescence (e.g. U.S. Pat. No. 6,270,644), sheath flow detectors (e.g. U.S. Pat. Nos. 5,468,364 and 6,048,444) and side-entry optical excitation geometry (e.g., U.S. Pat. Nos. 5,582,705 and 5,741,411).
[0009] The main drawback of the sheath flow detector is the highly sophisticated flow system that is needed to ensure a reliable sheath flow. Extreme demands are put on the optical and mechanical component tolerances in order to meet robustness demands of end-users.
[0010] The scanning confocal detector is based on scanning the optical system. The use of moving parts is not ideal when considering simplicity, robustness and lower costs of the instrument. The optical scanning principle also reduces the duty cycle per capillary, which may impair the sensitivity when scaling the instrument further for very high-throughput purposes.
[0011] Side-entry optical excitation geometry methods illuminate the interior of multiple capillaries simultaneously, and collects the light emitted from them. As in U.S. Pat. No. 5,790,727, the capillaries in a parallel array form an optical wave guide wherein refraction at the cylindrical surfaces confines illuminating light directed in the plane of the array to the core of each adjacent capillary in the array. In order to reduce light scatter, an optical wave-guide was used. Furthermore, a high powered laser source was needed because the laser beam was expanded to illuminate multiple channels.
[0012] LEDs as fluorescence excitation light sources have been used in single channel CE. In addition, multiplexed CE with fluorescence detection using LEDs as light sources was disclosed in U.S. Pat. No. 6,828,567. This system is based on a multi-radiation source/common detector configuration, in which detection is conducted in a time-staggered, and/or time-multiplexed detection for the channels. Each capillary was illuminated by a LED through optical fibers. The incident light from the light sources is separately directed to the multi-channel detection zones using optical fibers. The emitted light from the multi-channel detection zones also is directed to one or more common detectors using optic fibers. There may be more than one detector with multiple light sources in the entire detection system, each serving multiple radiation sources. The limitations of this scheme are that the number of multi-channels was limited by time-staggered strategies and detection cycle because of the sampling rate limitations. Therefore, only up to a 12-channel system was commercialized.
[0013] LED techniques have developed rapidly in recent years. High powered LED light sources with low cost are available from many commercial sources. The characteristics of LED light are different from lasers or conventional lamps. The LED output is not coherent as in laser light source, however LEDs have a narrow light spectrum and much higher optical output than conventional lamps at a specific wavelength.
[0014] It can be seen that in the continuing improvement of multiplexed CE systems there is therefore a need for a system of lower cost and less complexity in design that efficiently demonstrates accurate separation, high resolution and sensitive detection with a low cost of operation. This invention has as its primary goal fulfillment of this need.
BRIEF SUMMARY OF THE INVENTION
[0015] The present invention provides a simplified, low cost, high sensitivity, and high throughput multiplexed, capillary electrophoresis fluorescence detection system comprised of a single non-coherent light source as the excitation light source for all channels. An optical fiber bundle directs the emitted light from the LED to the capillary array detection window at an angle, preferably of about 45 ° relative to the capillary array holder. The emission output from the samples at the detection window is collected by a camera lens and registered with a two-dimensional imaging detector such as a charged coupled detector (CCD).
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a schematic of a multiplexed electrophoresis system of the present invention that uses fluorescence detection with a single LED light source positioned angularly as the excitation light source for the separation channels.
[0017] FIG. 2 depicts a 2D image output from the CCD detector.
[0018] FIG. 3 is an electropherogram result showing successful separation and detection using the system of FIG. 1 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0019] A specific embodiment of the invention is described in connection with FIG. 1 . It is, however, to be understood FIG. 1 is exemplary only and that other physical embodiments of the system may be employed without departing from the scope and spirit of the invention.
[0020] As earlier mentioned, the present invention provides a simple, low cost, efficient, highly sensitive and high throughput detection system referred to generally as 10 , based upon an optical fiber bundle 12 used to deliver a single LED light source 14 , instead of an expensive high-powered laser in a multichannel detection system, through a window 16 , at preferably an acute angle, the angle being most preferably 45°. The angle of this system is illustrated at 16 , the window at 18 and one capillary at 20 . An optical camera lens 22 is used for collecting the fluorescent signal and is recorded on a two-dimensional imaging array detector such as a charged couple device (CCD) detector 24 . In addition, pixel binning from the detector along the detection window signal is used to improve the signal to noise ratio without losing separation resolution. When imaging the fluorescent signal from the detection windows of the capillary array to the CCD detector, each capillary emission signal will cover more than one pixel on the CCD detector. For example, FIG. 2 depicts a 2D image output from the CCD detector while monitoring the detection window fluorescent signal. The fluorescent light from the detection window irradiates onto multiple pixels of the CCD detector. By combining the corresponding signals together (horizontally and vertically), a higher signal to noise ratio of the detection signal call be obtained.
[0021] Certain limits and parameters of the system are worthy of mention. Radiant flux of the light-emitting-diode (LED) can generally be from 100 mW to 1000 mW, and preferably is about 700 mW. Although one could use even higher radiant flux for excitation to increase the signal, higher background noise resulting from increased light scatter on the capillary detection surface would offset the gain. Therefore, one could use higher radiant flux if the larger light scatter can be reduced. Light from the diode is collected and illuminated upon the detection window 16 in an angular fashion, preferably at an angle from 20° to 90°, more preferably from 30° to 60° and most preferably at an angle of about 45°. The LED light can be collimated and focused onto the whole detection window; or an optical fiber bundle can be used to collect the light output from the LED light source onto the detection window directly. Using the optical fiber bundle is preferred because it is difficult to reshape the light output from the LED to match the shape of the detection window. However, the optical fiber bundle can be manufactured such that the input end has a similar collection area as the LED light source to maximize the light collection efficiency and the output end has a similar shape to the detection window to maximize the illumination efficiency. When the optical fiber bundle is used, lenses can be used to collimate the light output from the optical fiber bundle to the detection window. In the case of not using lenses, the output end of the optical fiber bundle is positioned as closely as possible to the detection window to minimize divergent output light. The later method is the preferred method because of the simple design.
[0022] The separation channels may be a capillary array 28 as illustrated in FIG. 1 , or they may in fact be just channels fabricated into a block (not shown). A system that has been used successfully is with the type of 96 capillary array shown for example in Yeung, U.S. Pat. No. 6,788,414 of Sep. 7, 2004.
[0023] The system of FIG. 1 was utilized for the fluorescence detection of a separated dsDNA sample as an example. The sieving matrix contained a dye such as ethidium bromide that binds to the dsDNA and that fluoresces when excited by the light source. The CCD detector recorded the fluorescence output from the detection windows. Software algorithms were used to extract and re-construct the signal output as electropherograms. FIG. 3 depicts a 100 base pair dsDNA ladder separation. The system showed at least 20 to 100 times better sensitivity than that of a UV absorption detection system comparable in cost.
[0024] It therefore can be seen that the invention accomplishes at least all of its stated objectives. | A multiplexed capillary electrophoresis (CE) method using fluorescence detection for a plurality of samples is improved economically and in terms of instrument complexity by irradiating the plurality of samples with a single non-coherent light source as the excitation light source for all of the channels. The preferred light source is a light-emitting-diode (LED). | 6 |
CROSS-REFERENCES TO RELATED APPLICATION
The present invention uses the symmetry modulation method of co-pending application, Ser. No. 08/281,754 filed Jul. 28, 1994 by Kenneth T. Small.
FIELD OF THE INVENTION
The present invention pertains to the field of electronic power conversion. More specifically, the present invention is related to an apparatus and method of providing a power-factor corrected (PFC), input to output isolated, 3-phase AC to DC power converter.
BACKGROUND OF THE INVENTION
Various power converter circuit topologies and control methods are well known. AC to DC switching power converters that provide both input to output isolation and power factor correction (PFC), may consist of a single-phase, single-stage flyback topology as shown in FIG. 1. If a large "hold up" energy-storage capacitor 101 across the DC input bus is omitted, and a control 102 is appropriate, the AC input current can be controlled to be proportional to the AC input voltage. This produces unity power factor. A number of commercially manufactured integrated circuit flyback-topology controllers are available for this application. Some examples are: Unitrode UC3852, Motorola MC342621 and Micro-Linear ML4813. All 3 may be used with a flyback transformer 103, to provide DC isolation.
One characteristic of this single-phase, single-stage PFC flyback topology is the absence of "hold up" time. This is because input capacitor 101 is absent, and can not supply energy during a momentary loss of input power. Another characteristic is that there will be considerable DC output voltage ripple, because output power droops during the low voltage portions of the AC input sine wave. These two characteristics are not important for many loads. In this situation the flyback converter has an advantage, because the converter operates well, without capacitor 101.
Flyback converters are cost effective for power factor corrected applications at power levels below a few hundred watts. However, at higher power, and relative to other topologies, flyback converters suffer from the following weaknesses: 1. Higher peak voltages and currents in a solid-state power switch 104. 2. Larger main transformer 103. 3. Higher RMS ripple current in an output capacitor 105.
In contrast, "boost" converter topologies are often used at higher power. A boost converter is shown in block 210 of FIG. 2. Boost converters suffer less from the above 3 weaknesses listed for flyback converters. However, boost converters do not provide DC (galvanic) isolation between their inputs and outputs. When isolation is required, an additional (transformer isolated) power conversion stage is added. Often, a "forward" converter topology is used for the second stage, as shown in Block 220 of FIG. 2. Forward converters are efficient, small, and low cost. They are usually used above a few hundred watts. Unfortunately, the second stage converts all power a second time, lowering overall efficiency.
The cost, space, and additional energy lost in second converter stage 220 are major shortcomings to this common approach of power factor correction. In addition, an energy storage capacitor 201 can not be omitted if not needed. The 2-stage circuit needs capacitor 201 between stages for proper operation.
FIG. 3 shows a prior-art high-power PFC converter operating from 3-phase AC power and providing input-output isolation. It is similar to three, prior-art single-phase AC converters in FIG. 2. This 3-phase converter requires two stages. The first PFC boost converter stage provides power factor correction, and the second forward converter stage provides input-output isolation by using a transformer. A total of 6 converters are required. It is possible to combine the three forward converters into one, but the result is still a two-stage conversion process. In 2 stage PFC, 3-phase converters, the increased cost, size, and efficiency loss due to converting the power twice, are a disadvantage.
Non-PFC single-stage forward converter topologies (full-bridge, half bridge, push-pull, 2-transistor unipolar, and 1-transistor transistor unipolar) are well known. They are well suited for high-power levels because they do not have the 3 weaknesses listed for flyback converters. Unfortunately, single-stage forward converters will not produce unity power factor. The problem is that forward converters will not draw any AC input current at or below a fixed voltage level on the AC input voltage sine wave. This is a result of the fixed voltage conversion ratio, determined by the turns ratio in the output transformer. Usually, the DC output voltage is relatively constant, due to a voltage control regulator, or a battery or large capacitor across the DC output terminals. When the AC input voltage passes through the low voltage portions of the AC sine wave, a forward converter can not produce voltage equal to the DC output voltage. This prevents the converter from delivering output current. Since the AC input current cannot be made to track the AC input voltage at low instantaneous input voltage, unity power factor correction is not produced by an otherwise desirable forward converter.
Therefore, there is a need in the prior art for a 3-phase AC to DC, high-power, input-output isolated, high-efficiency, PFC power converter. A single-stage converter would be desirable over a 2-stage converter. The prior-art, non-PFC forward converter topologies have cost, size, isolation, and efficiency advantages. It would be advantageous be able to use this topology if it could produce unity power factor. The converter (preferably) should not require an energy storage capacitor.
SUMMARY AND OBJECTS OF THE INVENTION
The present invention pertains to single-stage, 3-phase AC to DC, PFC power converters. In one embodiment, each AC phase is connected to a separate, transformer-isolated forward converter. The converter outputs are series connected after the output rectifiers. The output filter choke provides a relatively constant current load for all 3 converters. The current load allows each forward converter to operate at low instantaneous AC input voltage. The minimum input voltage restriction of prior-art forward converters is eliminated. A new control algorithm adjusts each converter "on" percent or duty (D) to be proportional to a sine wave. The sine wave corresponds to AC input voltage. This results in unity power factor. The control for all 3 converters is integrated into one, common circuit, that regulates and controls all converters.
Also, energy efficiency improves because power is converted only once, by a desirable and efficient forward converter. AC line frequency ripple components in the DC output cancel, reducing output ripple and noise.
In another similar embodiment, the converter outputs are series connected ahead of (rather than after) the output rectifiers. The number of rectifiers is reduced from six to two, reducing cost, size, and power loss. The desirable full-bridge type forward converters are used. Phase or symmetry modulation is used with three, full-bridge converters. The combination results in low output impedance during "off-time". This shorts the output transformer voltage, clamping the current drive from the other "on" converters, thereby permitting operation with fewer than 6 rectifiers. The same (new) integrated control, sets each "on" percent duty (D) of each of 3 converters, producing unity power factor. The timing of 3 converters is arranged to reduce transistor switching loss, and to simplify the transistor drive circuitry.
Further objects and advantages of my invention will become apparent from a consideration of the drawings and ensuing description.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which:
FIG. 1 is a simplified circuit diagram of a typical prior art flyback converter for producing unity power factor.
FIG. 2 is a simplified circuit diagram of a typical prior art 2-stage boost and forward converter for producing unity power factor.
FIG. 3 is a block diagram of a 3-phase prior-art converter. It uses 3 of the 2-stage converters shown in FIG. 2 to produce unity power factor.
FIG. 4 is a simplified schematic and block diagram of a 3-phase, single-stage converter of the present invention for producing unity power factor.
FIG. 5 is a simplified schematic diagram of a prior art full-bridge forward converter.
FIG. 6 is a simplified schematic diagram of a prior art half-bridge forward converter.
FIG. 7 is a simplified schematic diagram of a prior art push-pull forward converter.
FIG. 8 is a simplified schematic diagram of a prior art 2-transistor unipolar-pulse forward converter.
FIG. 9 is a simplified schematic diagram of a prior art 1-transistor unipolar-pulse forward converter.
FIG. 10 is a schematic diagram of a full-wave bridge rectifier and 3 transformer circuit of the present invention.
FIG. 11 is a schematic diagram of a full-wave center-tapped rectifier and 3 transformer circuit of the present invention.
FIGS. 12a to 12c are a simplified schematic diagrams of a prior art full-bridge converter. Included are pulse-timing diagrams of 2 modulation methods that are compatible with the present invention.
FIG. 13 is a simplified schematic and block diagram of an integrated control circuit of the present invention.
DETAILED DESCRIPTION
A 3-phase AC input, power factor corrected (PFC) power converter is described. In the following description, for purposes of explanation, many specific details are set forth, such as component values, voltages, currents, frequencies, etc., in order to provide a thorough understanding of the present invention. It will be obvious to one skilled in the art that the present invention may be practiced without these specific details. In other instances, well known structures are shown in block diagram form in order to avoid unnecessarily obscuring the present invention.
FIG. 4 shows a simplified schematic diagram of a first embodiment of the present invention. The outputs from forward converters A, B, and C are connected in series, after each pair of output rectifiers. Forward converters are a well known, general class of power converters where output power is transferred only during the portion of the switching cycle while the power transistor(s) is turned on. Most types of forward converters may be used by incorporating 3 of them into the circuit of FIG. 4. Some common, usable, forward converter circuits are shown in other figures as follows: FIG. 5 is a full-bridge, FIG. 6 is a half-bridge, FIG. 7 is a push-pull, FIG. 8 is a two transistor, unipolar output pulse type, FIG. 9 is a one transistor, unipolar output pulse type. Circuits in FIGS. 5, 8, and 7 use the 3 full-wave center-tapped output rectifier circuit shown in FIG. 4. Alternately, 3 full-wave bridge rectifiers may also be used. If FIG. 8 or 9 is used, the half-wave output rectifier circuit shown in FIG. 8 and 9 must also be included for substitution into FIG. 4.
The converters in FIG. 4 typically operate in the switching frequency range of 20 kHz to 200 kHz. The frequency is not critical, and may be chosen to balance cost, size, and efficiency factors. An output filter 410 is a typical L-C filter used with conventional forward converters. Inductor L in 410 is sufficiently large to maintain relatively constant current during the switching cycle. Inductor L provides a high AC impedance at the switching frequency across each converter output. This isolates each converter, and permits it to operate independently of others at any switching phase or switching frequency, with minimal interaction problems from the other converters. Whenever converter A, B, or C turns on, it draws current from its AC input that is proportional to the current flowing in inductor L. While a converter is off, the current drawn from its AC input is zero. Therefore, the average AC input current draw by a converter is proportional to current in inductor L, multiplied by an "on percent" or duty (D) of that converter. If desired, an L-C noise filter may be used to reduce switching current noise conducted back onto the AC input lines. If a individual converter duty (D) is controlled to be proportional to its AC input voltage, its resulting AC input current will be proportional to its AC input voltage. This represents unity power factor for that converter. Each converter is controlled in this manner, producing 3-phase unity power factor.
It is well known, that in a unity power factor polyphase AC system, total instantaneous power is constant over time. Because the 3 converter total input power is constant, the DC output power and inductor L current are also constant over the 3-phase AC input cycle. This permits the invention to be used where AC line frequency induced ripple in the DC output voltage is not desirable. In theory, using "ideal" components will simultaneously produce both unity power factor and zero output ripple related to the AC line frequency. In practice, there are losses and non-linearities in power semiconductors and magnetics. This precludes obtaining simultaneous unity power factor and zero ripple. However, a control algorithm may be adjusted slightly to favor either unity power factor or zero ripple, depending upon the application. Alternately, the converter may be optimized for unity power factor. An active or passive filter can then be added to the DC output to remove ripple components. The additional filter is practical, because output ripple power represents only a few percent of the total converter output power. Also, the dominant ripple frequencies are 6 and 12 times the AC line frequency, which filters more easily than AC line frequency.
In a second embodiment of the present invention, the circuit diagram in FIG. 4 is modified by substituting the transformer secondary and rectifier circuit from either FIG. 10 or FIG. 11 into FIG. 4. The change eliminates the individual output "catch" rectifiers for each converter. This results in a substantial energy and cost savings, especially if the DC output current is substantially above the AC input current. However, connecting 3 secondary windings in series without individual "catch" rectifiers is difficult. When "off", the primary-circuit output impedance of most forward converters (FIGS. 6,7,8,9) is high. When "off", they will series-block all output voltage from any other "on" converter. Therefore, these 4 converter types are not usable. To function correctly, a converter must have low impedance in the "off" state. FIG. 12 shows a pulse timing diagram of the 4 transistors in a full-bridge with "phase modulation" and with "symmetry modulation". Using either of these modulation methods will produce low primary-circuit output impedance in the "off" state. This is accomplished by using 2 of 4 full-bridge transistors to short both ends of the transformer primary to one input bus in the "off" state. Therefore, in the second embodiment, FIG. 12 full-bridge circuit and either 1 of the 2 illustrated modulation methods also are included in FIG. 4.
Phase modulation is further described as a full-bridge converter whose right and left bridge halves both operate with 50% top and 50% bottom duty. The phase relationship between left-half and right-half square waves is varied to control the output "on" percent or duty (D). Maximum output occurs when the two square waves are out of phase with each other. The output waveform is similar to a conventional pulse width modulated (PWM) full-bridge, except the converter primary output impedance is always low. Commercial available integrated circuits for phase modulation are manufactured by Micro Linear Corporation, San Jose, Calif. (Part # ML4818), and Unitrode Integrated Circuits Corporation, Merrimack, N.H. (Part # UC3875). Both companies provide application notes with more detailed theory and explanations.
Phase modulation is further described as a full-bridge converter with "on" percent determined by the "on" duration of the 2 lower bridge transistors. When a lower transistor is off, the transistor directly above is on. Lower bridge transistors alternate with equal "on" pulses, during the switching cycle. The converter primary output impedance is low in the "off" state, because the upper bridge transistors short circuit the transformer primary leads to the (+) input bus of the transistor bridge. More information on symmetry modulation can be found in a U.S. patent application entitled, Tolerant Power Converter, 08/281,754 filed Jul. 28, 1994 by Kenneth T. Small.
One additional requirement for the second embodiment of the present invention is the relationship between "on" pulses of the 3 converters. The switching frequency and phase of each converter must match the other converters. The secondary voltages of the 3 transformers must be in phase, so that their voltages will add, rather than subtract. As a practical matter, it is preferred and less complicated to start the "on" period of all three converters at the same time. If phase modulation is used, this will result in 1 vertical pair of transistors in each full-bridge converter having identical switching waveforms. This represents a simplification of the 3-converter, regulator control circuit.
Beginning all "on" periods together is also preferred. This allows the use of capacitors (approximately 0.01 uF) across each switching transistor or transformer primary. Capacitors reduce switching losses, which will allow an increase in switching frequency. Higher frequencies permit smaller magnetic components. This technique is sometimes used with single-phase, phase or symmetry modulated full-bridge converters. It uses the energy trapped in output transformer leakage inductance to charge the capacitors, rather than generating turn-on and turn-off switching losses in the transistors. Since the 3 transformer secondary windings are connected in series, the energy is shared and must be used simultaneously by all 3 converters to charge capacitors in all 3 converters. Starting "on" periods together accomplishes this.
FIG. 13 is a schematic and block diagram of the control circuit. It shows details of typical control hardware used to implement unity power factor, and output voltage regulation. FIG. 13 may be implemented with standard, multiple-sourced integrated circuits. A simple, voltage control loop is used. It is simplified to illustrate principles and basic features. Those familiar with power converter technology, will understand how to implement the details of well-known "circuit-functions" that appear as "blocks". Some other "housekeeping" functions are supplied within 3 pulse-width-modulator (PWM) control integrated circuits P1,P2,P3. FIG. 13 circuit is compatible with all embodiments of the invention, providing an appropriate PWM integrated circuit is utilized. Many operating principles were previously explained. Following is additional information and explanation of optional "enhancements" that improves performance.
The sine wave for each AC line input (phase A, B, C) is isolated by transformers (T1, T2, T3). Isolation allows the control circuit to be connected together, and referenced to the DC output voltage. The 3 AC voltages are rectified and scaled by a resistive voltage divider. Optional filters (F1, F2, F3) may be used to "filter-out" AC line noise transients, and to "clean-up" the sine waves present on the AC line phases. The filters prevent AC line transients from affecting the control loop and producing DC output noise. Also, some converter application specifications (such as IEC555-2) require sine-wave input currents with low harmonic-current content. With filters, poor AC line voltage waveforms do not increase AC line harmonic currents. The filters provide clean, rectified sign-waves to the control circuit, resulting in sine-wave AC line currents. The filters may be an active (or passive) low-pass type. Or, phase-locked-loops (PLL) may also be used (replacing F1, F2, F3) to generate 3 rectified-sine waveforms that are phase-locked to each AC input line. The 3 equal, constant-amplitude outputs from 3 PLL is an advantage in some applications. It causes the 3 AC input currents to be equal and balanced, even if there is a voltage difference between the 3 AC line inputs. Fortunately, only 1 (not 3) PLL are required. The fixed, 120 degree phase relationship between AC input phases allows one PLL to generate the 3 rectified-sine waveforms. Only 1 of the 3 AC input lines needs to be sensed to generate an AC "zero-crossing" signal. This signal can be obtained with an inexpensive opto-coupler circuit, eliminating T1, T2, T3, and related parts. Alternately, only T1 may be retained for the "zero-crossing" signal, and for supplying about 15 volts DC for control and transistor drive power.
An error amplifier 1310 in FIG. 13 compares a fixed reference voltage to the DC output voltage. An amplified and filtered "difference" or "error" signal 1320 is applied to multipliers M1, M2, M3. All 3 rectified sign waveforms are scaled (multiplied) by "error" signal 1320 within multipliers M1, M2, M3. "Error" signal 1320 sets the magnitude of the 3 rectified-sine waveform that are applied to pulse width modulator inputs of P1,P2,P3. This controls "on" percents of outputs Q1, Q2, Q3. The three individual power converters turn "on" in response to these outputs. An oscillator synchronization connection 1330, locks together the switching frequency and phase of P1,P2,P3 and all converters.
Common housekeeping and control functions are included with many PWM integrated circuits used for P1,P2,P3. These functions include: output current control, soft-start, sync, paralleling, undervoltage lockout, etc. Only 1 PWM integrated circuit is needed to supply these functions. Therefore, these duplicated functions will be unused in the other 2 PWM integrated circuits.
Also, the control circuit is physically large and complex because it consists of approximately 5 to 10 standard integrated circuits. Fortunately, the control circuit (excluding transformers) contains few (if any) components that can not be easily integrated into a single, dedicated integrated circuit that will replace the 5 to 10 integrated circuits of FIG. 13. This would eliminate unused features in PWM P2 and P3. It is also possible to integrate a single version of the control circuit that will work with all embodiments of the present invention. This is an advantage because it eliminates the cost of designing multiple integrated circuit versions of the control circuit.
In the foregoing specification, the invention has been described with reference to specific exemplary embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention as set forth in the appended claims. The specification and drawings are, accordingly to be regarded in an illustrative rather than a restrictive sense. Thus, a three-phase AC power converter with power factor correction is disclosed. | A solid-state, PFC power converter for converting 3-phase AC to DC in a single, isolated conversion step, using 3 forward converters. Converter outputs share a common output choke, permitting operation at low instantaneous AC input voltage. Each forward converter is "duty" modulated proportional to its rectified AC input voltage, producing unity input power factor. The constant of proportionality for 3 converters is controlled to regulate the DC output voltage. A control circuit provides immunity to AC input distortion and noise. The control circuit operates with various forward converter topologies, and is compatible with integrated circuit processes. A version using phase or symmetry modulated full-bridge converters, requires only 2 output rectifiers. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims the benefit and incorporates by reference the entire disclosure of U.S. Provisional Application No. 60/517,399, filed Nov. 6, 2003.
FIELD OF THE INVENTION
[0002] The present invention relates generally to the detection and measurement of nucleic acids. More particularly, it relates to a novel method of detecting and measuring specific sequences of nucleic acids from biological materials.
BACKGROUND OF THE INVENTION
[0003] The detection and measurement of specific nucleic acid sequences have become an important tool for basic genetic research, medical and veterinary diagnosis/prognosis, and forensic science. A number of techniques have been developed to detect and measure nucleic acid sequences, however, with the recent publication of the sequence of the human genome as well as the sequences of a variety of non-human genomes ranging from mice to bacteria, considerable excitement has been engendered by the so-called gene microarray technology. This relatively new technology offers the potential of simultaneously detecting and measuring thousands of nucleic acid sequences. Indeed, the human genome has approximately 35,000 genes, and gene microarray technology has the potential of enabling the detection and measurement all human genes simultaneously. The notion behind this technology is to utilize the inherent ability of single stranded nucleic acids (both deoxyribonucleic acid or DNA and ribonucleic acid or RNA) to hybridize to a complementary single-strand oligonucleotide sequence through Watson-Crick base-pairing in order to detect the presence and amount of specific nucleic acid sequences in biological samples.
[0004] One of the most exciting areas to which gene microarray technology is being applied is functional genomics. While knowledge of the sum total of the genes in a genome is extremely important, it is perhaps more important to know which of these genes are functioning at a particular time in a particular cell or tissue. For genes represented in the DNA to function they must first be transcribed into messenger RNA (mRNA), and the mRNA must then be translated into protein. By measuring specific mRNA sequences one can determine which of the genes represented in the genome are functioning at a particular moment in time. Many disease states in humans and animals are characterized by a change in gene function in certain cells or tissues, and detection of the pattern of gene expression is useful, therefore, for both diagnosis and prognosis.
[0005] In a common embodiment of the gene microarray technology, RNA is removed from cells or tissues by an extraction procedure, and then after purification of the mRNA it is subjected to reverse transcription, an enzymatic process whereby the mRNA is converted into a complementary DNA (cDNA). During this reverse transcription process either fluorophore-labeled nucleotides, or nucleotides with chemical side-groups that allow fluorophores to be attached, are added. After the cDNA is fluorophore-labeled, it is added to a detection system usually involving a complementary oligonucleotide attached to a solid substrate. Under conditions suitable for hybridization, the fluorophore-labeled cDNA is “captured” to the solid surface by complementary base pairing, and then following a wash step to remove the non hybridized cDNA, the hybridized cDNA is measured by one of several standard fluorimetric techniques. The end result of this procedure is the detection, and in some cases, quantification of the expression of specific genes by the measurement of their mRNAs.
[0006] Notwithstanding the attributes of modern gene microarray technology, it has many problems that need new solutions. For instance, when used for gene expression analysis, the mRNA to be measured must be purified from the cells or tissue and then converted enzymatically into cDNA in order to add the fluorophore. This is a time consuming technique that requires a sophisticated laboratory with expensive equipment and reagents. Moreover, because the method involves a washing step to remove the unhybridized cDNA, it cannot be performed in a single step.
BRIEF SUMMARY OF THE INVENTION
[0007] The present invention provides improved methods for detecting and measuring specific nucleic acids. In one aspect, the present invention provides nucleic acid detection methods that are rapid and cost-effective. In another aspect, the present invention provides in vitro, in vivo, or in situ diagnostic methods for quantitatively measuring multiple, specific nucleic acid sequences from biological samples.
[0008] According to some embodiments, the nucleic acid detection and measurement methods of the present invention do not require RNA purification, production of cDNA by reverse transcription, or chemical labeling of the nascent cDNA strand. Moreover, the methods can be reversible and do not require a wash step; thus they are suitable for real-time in vivo or in situ gene expression analysis.
[0009] Like the majority of nucleic acid detection methods using gene microarrays, many embodiments of the invention use a single-stranded DNA capture oligonucleotide with a sequence complementary to that of the nucleic acid to be measured. This capture oligonucleotide can also be other detectable nucleic acid molecules, such as RNA, 2′-O-methyl oligoribonucleotide, or have a chemically modified backbone such as a backbone based on peptide linkages or a backbone with phosphorothiolates instead of phosphate groups. This capture oligonucleotide can be used either in solution or attached to a substrate support. Various methods are known in the art for attachment of an oligonucleotide to a substrate support. The attachment can be covalent or non-covalent. For instance, a functional chemical group can be incorporated into the oligonucleotide. The functional chemical group can form a covalent bond to another functional chemical group on the support. Examples include, but are not limited to, functional groups that can be incorporated into the stem-loop strand using phosphoramidite precursors in standard solid phase synthesis. Some specific examples of these function groups are: thiol or disulfide groups for self-assembly onto a metal (e.g. gold, silver, copper) surface or for reaction with a substrate surface that is derivatized with thiol or disulfide reactive groups (e.g. acrylamide, epoxide, thiol); an amino group for reaction with a substrate surface that is derviatized with amino reactive groups (e.g. carboxylic acids, succinimides, anhydrides); or an acrylamide group for reaction with a substrate surface that is derviatized with acrylamide reactive groups (e.g. thiols). The following references are provided as examples of methods of attaching oligonucleotides to substrate supports: Fodor et al., U.S. Pat. No. 5,744,305; Beier and Hoheisel (1999) Nucleic Acids Research 27:1970-1977; Niemeyer and Blohm (1999) Angew. Chem. Int. Ed. 38:2865-2869; Rogers, Y-H. et al. (1999) Anal. Biochem. 266: 23-30; Schena, M. “DNA Microarrays. A Practical Approach”, Oxford University Press, New York, N.Y., (1999); Schena, M. “Microarray Biochip Technology”, Eaton Publishers., Natrick, Mass., (2000); Zammatteo, N. et al. (2000) Anal. Biochem. 280:143-150; Pirrung, M. C. (2002) Angew. Chem. Int. Ed. 41: 1276-1289; Charles, P. T. et al. (2003) Langmuir 19:1586-1591. Schena, M. “Microarray Analysis”, Wiley-Liss, Hoboken, N.J., (2003), all of which are incorporated herein by reference in their entireties.
[0010] In one embodiment of the invention, the capture oligonucleotide is not directly attached to a surface, but rather has a 3′ sequence complementary to that of an address oligonucleotide that is chemically attached to the surface. This attachment means avoids the expense of having the longer capture oligonucleotide chemically modified at its 3′ end to enable chemical attachment directly to the surface. Moreover, this facilitates the easy self-assembly of the capture oligonucleotides on the substrate surface. Another feature of the single-stranded capture oligonucleotides of this embodiment is that they have base sequences that cause them to form hairpins or stem-loops at room temperature. However, when these capture oligonucleotides hybridize with a complementary nucleic acid strand, the single-stranded capture oligonucleotides can no longer form the hairpin or stem-loop secondary structures but remain in the linear configuration. Another feature of the capture oligonucleotides of this embodiment is that they include 5′ tail segments with a common sequence that enables the hybridization of a fluorophore-labeled reporter oligonucleotide sequence. When the hairpins are in the open configuration, excitation of the fluorophores attached to the hybridized reporter oligonucleotides results in a characteristic emission of photons (fluorescence). However, when the capture oligonucleotides are in the closed hairpin or stem-loop configuration, the fluorophores on the reporter oligonucleotides are brought into close proximity to guanosine bases strategically placed 3′ to the point where the hybridized bases form the hairpin or stem-loop (hairpin-forming sequences). Upon excitation of the fluorophores under these conditions, the fluorescence emissions are quenched. This quenching preferably is reversible.
[0011] Other quenching mechanisms can also be used in the present invention. For instance, photoinduced electron transfer (or photoinduced charge transfer) may occur between luminescence compounds (fluorescence, phosphorescence, and electroluminescence) or luminescent nanoparticles and naturally occurring nucleotides (e.g., guanosine nucleotides), synthetic nucleotide analogs, other synthetic quenchers (including quenchers that intercalate into DNA or RNA duplexes, or quenchers that can be incorporated into an oligonucleotide from a precursor such as a phosphoramidite monomer by solid-phase oligonucleotide synthesis), or metals (e.g., bulk or nanoparticles) as quenchers. Some examples are illustrated in (but not exclusive to) the references below: Schena et al., (1995) Science 270:467-470; Claus, et al. (1996) J. Phys. Chem. 100:5541-5553; Lewis and Wu, (2001) J. Photochem, and Photobiol. C: Photochem. Rev. 2: 1-16; Lewis, et al. (2001) Acc. Chem. Res. 34:159-170; Prasanna de Silva et al. (2001) Trends in Biotechnol 19:29-34; Torimura et al., (2001) Anal. Sci. 17:155-160; Thomas et al. (2002) Pure Appl. Chem. 74:1731-1738; Vullev et al., (2002) Res. Chem. Intermed. 28:95-815; Yamane, A. (2002) Nucleic Acids Research 30: e97; Du et al., (2003) J. Am. Chem. Soc. 125: 4012-4013; Kawai, K., and Majima T. (2003) J. Photochem. Photobiol. C: Photochem. Rev. 3: 53-66; May, et al. (2003) Chem. Comm. 970-971, all of which are incorporated herein by reference in their entireties. All of these quenchers can be incorporated or attached to the capture oligonucleotides of the present invention.
[0012] Many embodiments of the present invention afford several significant improvements to standard nucleic acid detection and measurement technology. For example, many capture oligonucleotides of the present invention do not require any chemical modifications for attachment to the substrate surface or for incorporation of a fluorophore, and therefore can be synthesized economically. For another example, many capture oligonucleotides of the present invention can be self-assembled on one or more substrate supports, thereby making the manufacturing of the nucleic acid detector quick and inexpensive. In one embodiment, each one of the thousands of capture oligonucleotides in a large array has the same tail sequence, thereby allowing the use of a single fluorescent reporter oligonucleotide. In another embodiment, the fluorescence quenching output is reversible, and all components of the detection system are immobilized. This allows for real-time in situ nucleic acid detection.
[0013] In one aspect, the present invention provides nucleic acid arrays comprising a substrate and a nucleic acid complex. The nucleic acid complex comprises an anchor nucleic acid molecule that is stably attached to the substrate, and an oligonucleotide of the present invention that is hybridized to the anchor nucleic acid molecule. The oligonucleotide comprises (1) a hairpin-forming sequence capable of forming a stem-loop and (2) a reporter-binding sequence capable of hybridizing under nucleic acid array hybridization conditions to a fluorophore-labeled reporter sequence. In many instances, the reporter-binding sequence is complementary to the fluorophores-labeled reporter sequence.
[0014] Formation of the stem-loop in the oligonucleotide modifies the fluorescence signals of the fluorophore-labeled reporter sequence when the reporter sequence is hybridized to the oligonucleotide. In many cases, formation of the stem-loop quenches the fluorescence signals of the fluorophore-labeled reporter sequence. For instance, formation of the stem-loop can quench the fluorescence signals of the reporter sequence by at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% or more, as compared to that when the stem-loop is in an open configuration. In many other cases, disruption of the stem-loop produces a detectable increase in the fluorescence signals of the fluorophore-labeled reporter sequence when the reporter sequence is hybridized to the oligonucleotide. Disruption of the stem-loop can be achieved, for example, by hybridization of the oligonucleotide to a suitable target sequence which forms base-pairing with at least part of the hairpin-forming sequence.
[0015] In one embodiment, an oligonucleotide of the present invention is stably associated with a nucleic acid array via hybridizing to an anchor nucleic acid molecule, and the oligonucleotide is also hybridized to a fluorophore-labeled reporter sequence. The oligonucleotide may or may not form the stem-loop or be hybridized to the target sequence. In addition to the use of an anchor nucleic acid molecule, the present invention also contemplates the use of other means for attaching oligonucleotides to nucleic acid arrays, as appreciated by those of ordinary skill in the art.
[0016] In one specific example, an oligonucleotide of the present invention comprises at least one guanine base (such as 1, 2, 3, 4, 5, or more guanosines). Formation of the stem-loop in the oligonucleotide brings the guanine base(s) into close proximity to the fluorophore-labeled reporter sequence when the reporter sequence is hybridized to the oligonucleotide, thereby quenching the fluorescence signals of the reporter sequence.
[0017] In another specific example, an oligonucleotide of the present invention comprises, from the 3′ end to the 5′ end (or from the 5′ end to the 3′ end), a reporter-binding sequence, a hairpin-forming sequence, one or more guanine base(s), and a sequence capable of hybridizing to an anchor nucleic acid molecule.
[0018] Any type of nucleic acid array is contemplated by the present invention, such as traditional microarrays, bead arrays, or microplates. Each of the nucleic acid arrays includes a plurality of discrete regions. The locations of these discrete regions on a nucleic acid array are either predefined or determinable. Each discrete region may be stably associated with an anchor nucleic acid molecule. The anchor molecules in different discrete regions preferably have the same sequence. Anchor molecules with different sequences can also be used.
[0019] Each anchor molecule can be hybridized to an oligonucleotide of the present invention. The oligonucleotide in each different discrete region preferably is different, e.g., comprising a different target-binding sequence. The oligonucleotides in different discrete regions can also have the same target-binding sequence. In one embodiment, a nucleic acid array of the present invention includes at least 5, 10, 20, 30, 40, 50, 100, 500, 1,000, or more different capture oligonucleotides of the present invention.
[0020] Capture oligonucleotides can also be stably attached to a nucleic acid array without binding to the anchor molecules. These capture oligonucleotides can be attached to different discrete regions on a nucleic acid array via covalent or non-covalent interactions.
[0021] The present invention also features nucleic acid complexes comprising an oligonucleotide of the present invention. The oligonucleotide comprises a reporter-binding sequence that is hybridized to a fluorophore-labeled reporter sequence. The oligonucleotide also comprises a hairpin-forming sequence capable of forming a stem-loop. Formation of the stem-loop modifies (e.g., quenches) the fluorescence signals of the reporter sequence. Disruption of the stem-loop (e.g., by hybridizing to a target sequence) can produce a detectable change (e.g., an increase) in the fluorescence signals of the fluorophore-labeled reporter sequence.
[0022] In addition, the present invention features methods for detecting the presence or absence of a target sequence. The methods comprise the steps of:
[0023] hybridizing an oligonucleotide of the present invention to a nucleic acid sample and a fluorophore-labeled reporter sequence, wherein the oligonucleotide comprises (1) a hairpin-forming sequence capable of forming a stem-loop and (2) a sequence capable of hybridizing under nucleic acid array hybridization conditions to the fluorophore-labeled reporter sequence, wherein the oligonucleotide is capable of hybridization under nucleic acid array hybridization conditions to the target sequence, and hybridization of the oligonucleotide to the target sequence prevents formation of the stem-loop in the oligonucleotide, and wherein formation of the stem-loop quenches fluorescence signals of the fluorophore-labeled reporter sequence when the reporter sequence is hybridized to the oligonucleotide; and
[0024] detecting the fluorescent signals of the reporter sequence.
[0000] An increase in fluorescence signals of the fluorophore-labeled reporter sequence in the presence of the nucleic acid sample compared to that in the absence of the nucleic acid sample is suggestive of the presence of the target sequence in the sample, while no significant change in fluorescence signals of the fluorophore-labeled reporter sequence in the presence of the nucleic acid sample compared to that in the absence of the nucleic acid sample is suggestive of the absence of the target sequence in the sample.
[0025] Furthermore, the present invention features methods for detecting sequence differences between a target sequence and a sequence of interest. The methods comprising the steps of:
[0026] hybridizing an oligonucleotide of the present invention to the sequence of interest and a fluorophore-labeled reporter sequence, wherein the oligonucleotide comprises (1) a hairpin-forming sequence capable of forming a stem-loop and (2) a sequence capable of hybridizing under nucleic acid array hybridization conditions to the fluorophore-labeled reporter sequence, wherein the oligonucleotide comprises a sequence that is complementary to the target sequence, and hybridization of the target sequence to the oligonucleotide prevents formation of the stem-loop in the oligonucleotide, and wherein formation of the stem-loop quenches fluorescence signals of the fluorophore-labeled reporter sequence when the reporter sequence is hybridized to the oligonucleotide; and
[0027] detecting the fluorescent signals of the reporter sequence.
[0000] A decrease in fluorescence signals of the fluorophore-labeled reporter sequence in the presence of the sequence of interest compared to that in the presence of the target sequence (e.g., in the same concentration as the sequence of interest), together with an increase in fluorescence signals of the fluorophore-labeled reporter sequence in the presence of the sequence of interest compared to that in the absence of the sequence of interest, is suggestive that the sequence of interest is homologous to but different from the target sequence. In one example, the sequence difference between the target sequence and the sequence of interest is a single nucleotide mutation. Examples of single nucleotide mutations amenable to the present invention include, but are not limited to, nucleotide substitution, deletion, addition, or another modification that affects base-pairing ability. The present invention also contemplates detection of two or more nucleotide differences between the target sequence and the sequence of interest.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The drawings are provided for illustration, not limitation.
[0029] FIG. 1 illustrates the components of a nucleic acid detection and measurement system of the present invention.
[0030] FIGS. 2A-2C contrast two known forms of G-base quenching (A and B) with a novel G-base quenching of the present invention (C).
[0031] FIGS. 3A-3C demonstrate the operation of a nucleic acid detection and measurement system of the present invention. FIG. 3A shows an open configuration of a capture nucleic acid; FIG. 3B indicates hybridization with a target molecule; and FIG. 3C illustrates formation of a stem-loop in the capture nucleic acid.
[0032] FIGS. 4A-4C indicate different experimental configurations used to show that G bases on the hairpin loop of the capture oligonucleotide (CO) cause fluorescence quenching of RO-TAMRA.
[0033] FIG. 5 shows fluorescence spectra demonstrating that G bases on the hairpin loop of the capture oligonucleotide cause fluorescence quenching of RO-TAMRA.
[0034] FIGS. 6A and 6B depict two experimental configurations used to demonstrate that hybridization of a target oligonucleotide traps the capture oligonucleotide in the hairpin-opened form and thus decreases the quenching of RO-TAMRA by the proximal G bases.
[0035] FIG. 7 shows fluorescence spectra demonstrating that the effect of a 24mer target on the emission intensities of the RO-CO and RO-CCO hybrids.
[0036] FIG. 8 shows the detection of a 24mer target by RO-CO hybrid at room temperature (no premixing or preheating of 24mer with CO).
[0037] FIG. 9 illustrates the detection of B7-67mer by RO-CO hybrid at room temperature (no premixing or preheating of B7-67mer with CO).
[0038] FIG. 10 describes the effect of the address oligo on quenching.
[0039] FIG. 11 illustrates that a single base mismatch between a target oligonucleotide and the sequence in the capture oligonucleotide can be detected as a difference in emission intensity.
DETAILED DESCRIPTION OF THE INVENTION
I. Definitions
[0040] In order that the present invention may be more readily understood, certain terms are first defined. Additional definitions are set forth throughout the detailed description.
[0041] In this application, the use of the singular includes the plural unless specifically stated otherwise. Also, the use of “or” means “and/or” unless state otherwise.
[0042] The terms “target nucleic acid” refers to the nucleic acid sequence that is to be detected or measured using the improved methods of the present invention. A target nucleic acid may be deoxyribonucleic acid (DNA), ribonucleic acid (RNA, including messenger ribonucleic acid or mRNA), or other types of nucleic acid molecules.
[0043] The term “base pair” refers to a pair of nucleotide bases (nucleotides) each in a separate single stranded nucleic acid in which each base of the pair is non-covalently bonded to the other (e.g., via hydrogen bonds). For instance, a Watson-Crick base pair usually contains one purine and one pyrimidine. Guanosine can pair with cytosine (G-C), adenine can pair with thymine (A-T), and uracil can pair with adenine (U-A). The two bases in a base pair are said to be complementary to each other.
[0044] The term “oligonucleotide”, as used herein, refers to a molecule comprised of two or more nucleic acid residues (e.g., deoxyribonucleotides, ribonucleotides or modified forms thereof). Any method can be used to prepare oligonucleotides of the present invention. For instance, oligonucleotides can be synthesized chemically, or expressed from a suitable construct or vector. As used herein, an oligonucleotide can be a polynucleotide and comprise at least 10, 20, 30, 40, 50, or more nucleotide residues.
[0045] The terms “hybridization” or “hybridize” include the specific binding of two nucleic acid single strands through complementary base pairing. Hybridization typically involves the formation of hydrogen bonds between nucleotides in one nucleic acid strand and their corresponding nucleotides in the second nucleic acid strand.
[0046] The term “melting temperature” (T m ) is defined as the temperature at which 50% of the nucleic acid strands in a specific nucleic acid duplex dissociate at a defined ionic strength, pH, and nucleic acid concentration. For hybrids less than 18 base pairs in length, T m (° C.) may be calculated as T m =2(# of A+T bases)+4(# of G+C bases). For hybrids between 18 and 49 base pairs in length, T m (° C.) may be calculated as T m =81.5+16.6(log 10 Na + )+0.41(% G+C)−(600/N), where N is the number of bases in the hybrid, and Na + is the molar concentration of sodium ions in the hybridization buffer.
[0047] The terms “hairpin or stem-loop”, as used herein, describe a secondary structure formed by a single-stranded oligonucleotide when complementary bases in one part of the linear strand hybridize with bases in another part of the same strand.
[0048] The term “capture oligonucleotide” includes, but is not limited to, a single-stranded sequence of nucleotide bases made up of the following segments of nucleotides progressing from the 3′ terminus to the 5′ terminus (note that this description applies to a sequence attached to a substrate at its 3′ end, but a capture sequence can be similarly prepared for attachment at its 5′ end): 1) a variable length sequence at the 3′ terminus complementary to a particular address oligonucleotide sequence; 2) a sequence of guanosine bases positioned just 3′ of the hairpin or stem-loop sequence; 4) a sequence of bases of variable length complementary to a sequence in the nucleic acid that is to be detected and measured, 5) a sequence that is complementary to the first 5 to 15 bases in the nucleic acid recognition sequence (note that this can include probes that use exclusively the loop region as the nucleic acid recognition sequence), and that upon hybridization forms a hairpin or stem-loop secondary structure; and 6) a sequence of bases of variable length ending at the 5′ terminus that are complementary to the sequence of a fluorophore-labeled reporter oligonucleotide. Heating the hairpin-forming sequence to its melting temperature or hybridization with the target nucleic acid can linearize the capture oligonucleotide. Each functional segment in the above-described capture molecule can be re-arranged as desired. In addition, the guanosine bases can be replaced by other naturally occurring, modified or synthetic bases, provided that desirable fluorescence quenching can be achieved. Other quenching moieties can also be employed in the capture molecule.
[0049] The term “address oligonucleotide” includes, but is not limited to, a single-stranded sequence of nucleotide bases derivatized on either its 5′ or 3′ end with a functional group capable of forming a covalent bond with a functional group on a substrate. For the purpose of illustration only, the functional group on the address oligonucleotide could be an amino group and the functional group on the substrate could be a carboxyl group, thus enabling the formation of an amide linkage. The address oligonucleotide has a base sequence that is complementary to a base sequence at either the 5′ or 3′ terminus of the capture oligonucleotide. Hybridization of the capture oligonucleotide with the surface-immobilized address oligonucleotide results in the tethering of the capture oligonucleotide to the substrate. Microarrays with a universal set of address sequences can be used for any targets simply by controlling the combination of the sequences of the address-binding region and the target-binding region of the capture oligonucleotide. Also, the length and number of complementary bases in the address oligonucleotide can be varied to affect the desired strength of the tether (melting temperature).
[0050] The term “self-assembly” as used herein refers to the attachment of the capture oligonucleotide to the surface substrate by hybridization with the address oligonucleotide, and also to the attachment of the reporter oligonucleotide to the capture oligonucleotide by hybridization.
[0051] The term “guanosine bases” refers to one or more guanosine nucleotides in either a single-stranded nucleic acid sequence, or in a double-stranded nucleic acid sequence in which the guanosine bases are base paired with cytosine bases.
[0052] The term “G-base quenching” describes the reduction in fluorescence emission of a fluorophore when in close proximity to guanosine bases in the sequence of a single or double-stranded nucleic acid.
[0053] The phrase “target nucleic acid recognition sequence” represents the single-stranded sequence within the capture oligonucleotide that is complementary to a sequence in a target nucleic acid. The target nucleic acid recognition sequence can include any portion of the sequence of the loop or one arm of the stem of the capture oligonucleotide. The target nucleic acid recognition sequence can also be exclusively the sequence of the loop. In the case of MnRNA, the sequence would be complementary to a sequence in the single-stranded MnRNA.
[0054] The term “hairpin-forming sequence” refers to a sequence in the capture oligonucleotide that can form a hairpin structure. In one specific example, the hairpin-forming sequence is adjacent to, overlaps or includes the target nucleic acid recognition sequence.
[0055] The term “quench” means a relative reduction in the fluorescence intensity of a fluorescent group as measured at a specified wavelength as well as the complete reduction, regardless of the mechanism by which the relative reduction is achieved. As specific examples, the quenching may be due to molecular collision, energy transfer such as FRET, a change in the fluorescence spectrum (color) of the fluorescent group or any other mechanism. The amount of the relative reduction is not critical and may vary over a broad range. The only requirement is that the reduction be reliably measurable by the detection system being used. Thus, a fluorescence signal is “quenched” if its intensity at a specified wavelength is reliably reduced by any measurable amount. The reduction can be, for example, at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, even 100%, as compared to the original fluorescent intensity.
[0056] The phrase “stably attached,” means that an oligonucleotide maintains its relative position on a substrate during hybridization and subsequent signal detection. An oligonucleotide can be stably attached to a substrate by non-covalent or covalent interactions.
[0057] The phrase “nucleic acid array hybridization conditions” are sequence-dependent and will be different in different circumstances. Longer sequences hybridize specifically at higher temperatures. An extensive guide to the hybridization of nucleic acids is found in Tijssen, Techniques in Biochemistry and Molecular Biology—Hybridization with Nucleic Probes, “Overview of principles of hybridization and the strategy of nucleic acid assays” (1993). Generally, high stringent nucleic acid array hybridization conditions are selected to be about 5-10° C. lower than the T m for the specific sequence at a defined ionic strength pH. Low stringent nucleic acid array hybridization conditions are generally selected to be about 15-30° C. below the T m . Typically, nucleic acid array hybridization conditions will be those in which the salt concentration is less than about 1.0 M sodium ion, typically about 0.01 to 1.0 M sodium ion concentration (or other salts) at pH 7.0 to 8.3 and the temperature is at least about 30° C. for short probes (e.g., 10 to 50 nucleotides) and at least about 60° C. for long probes (e.g., greater than 50 nucleotides). Nucleic acid array conditions can also include the use of destabilizing agents such as formamide. For selective or specific hybridization, a positive signal preferably is at least two times background, and more preferably, is at least 10 times background.
II. The Invention
[0058] In one aspect, the present invention features a nucleic acid complex which comprises a capture oligonucleotide hybridized to a fluorophore-labeled probe sequence. The capture oligonucleotide comprises a hairpin-forming sequence and is capable of hybridizing under nucleic acid array hybridization conditions to a target sequence. The hairpin formation by the hairpin-forming sequence can modify the fluorescence signals of the probe sequence. Hybridization of the target sequence to the capture oligonucleotide disrupts the hairpin formation, thereby producing a detectable change in the fluorescence of the probe sequence. The detectable change may be a change in any fluorescence property, such as intensity, maximum emission or excitation wavelength, or fluorescence decay property. The modification of the fluorescence signals by the hairpin structure can be, for example, G-base quenching or any other fluorescence property modification.
[0059] In one specific example, the nucleic acid complex includes both the target and probe sequences hybridized to the capture oligonucleotide.
[0060] In another aspect, the present invention features a nucleic acid array which includes a nucleic acid complex. The nucleic acid complex includes a capture oligonucleotide hybridized to an anchoring sequence stably attached to a substrate of the nucleic acid array. The capture oligonucleotide also includes a hairpin-forming sequence and is capable of hybridizing under nucleic acid array hybridization conditions to a target sequence and a fluorophore-labeled probe sequence Concurrent hairpin formation by the hairpin-forming sequence and hybridization of the probe sequence to the capture oligonucleotide modify the fluorescence signals of the probe sequence. Hybridization of the target sequence to the capture oligonucleotide disrupts the hairpin formation, thereby producing a detectable change in the fluorescence signals of the probe sequence.
[0061] The present invention contemplates any type of nucleic acid array, including bead arrays in which nucleic acid complexes are stably attached to numerous beads. The substrate of the nucleic acid array can be made of any material, such as glasses, silica, ceramics, nylon, quartz wafers, gels, metals, and paper.
[0062] In one specific example, the nucleic acid complex on the nucleic acid array includes both the target and probe sequences hybridized to the capture oligonucleotide. In another specific example, the nucleic acid complex includes the probe sequence hybridized to the capture oligonucleotide. The nucleic acid complex also comprises a hairpin structure formed by the hairpin-forming sequence. The fluorescence signals of the probe sequence are quenched due to the formation of the hairpin structure.
[0063] In yet another aspect, the present invention features a method useful for detecting or measuring a target sequence of interest. The method includes the steps of hybridizing a capture oligonucleotide to a nucleic acid sample and a fluorophore-labeled probe sequence, and detecting the fluorescent signals of the probe sequence. The capture oligonucleotide includes a hairpin-forming sequence and is capable of hybridizing under nucleic acid array hybridization conditions to the target sequence. Concurrent hairpin formation by the hairpin-forming sequence and hybridization of the probe sequence to the capture oligonucleotide modify the fluorescence signals of the probe sequence. Hybridization of the target sequence to the capture oligonucleotide disrupts the hairpin formation, thereby producing a detectable change in the fluorescent signals of the probe sequence.
[0064] In one embodiment for detecting and measuring the class of nucleic acids known as mRNA (for example only as one class of nucleic acids that can be detected by the method of the present invention), a hairpin or stem-loop structure of capture oligonucleotide is synthesized using standard nucleic acid synthesis techniques. Other techniques like polymerase chain reaction are known in the art and can be used to manufacture the capture oligonucleotide sequence. Although a single sequence is described, it is understood that thousands of these sequences can be made and tested simultaneously in a gene expression array. The components of the improved method are illustrated in FIG. 1 . For illustrative purposes, a single-stranded DNA oligonucleotide is shown, the length of which can vary depending on the requirements for detection as will become apparent in the following description. Beginning at its 3′ terminus, the capture oligonucleotide 1 has a sequence of variable length that is complementary to a single-stranded address oligonucleotide 2 that is attached to a substrate surface 3 such as glass or gold-coated silica. Watson-Crick base-pairing or hybridization of these two sequences results in the attachment or self-assembly of the capture oligonucleotide 1 to the substrate surface 3 . Continuing in a 5′ direction, the next required sequence is a series of guanosine (G) bases 4 in the positions indicated. The need for these guanosine nucleotides will be described below. Next in the 5′ direction is a sequence of nucleotides that are complementary to a sequence in the mRNA of the gene to be measured. This mRNA recognition sequence 5 can be shorter or longer than shown in the illustration. Next is a sequence of nucleotides complementary to nucleotides in the mRNA recognition sequence. In this hairpin-forming sequence 6 , the number of complementary bases can be shorter or longer than illustrated. Hybridization of these bases to their complementary bases results in the formation of a secondary structure called a hairpin or stem-loop 7 . Finally, it can be seen in FIG. 1 that there is a “tail” structure consisting of unpaired nucleotides that form the 5′ terminus of the capture oligonucleotide sequence. This 5′ tail sequence 8 can be shorter or longer than that illustrated. The sequence of these bases is complementary to an oligonucleotide sequence called the reporter oligonucleotide 9 . From the illustration, it can be seen that the reporter oligonucleotide has a fluorophore 10 attached at its 5′ end.
[0065] Certain fluorophores chemically attached to oligonucleotide strands will exhibit a characteristic fluorescence emission when excited by light at a characteristic wavelength, and that this characteristic fluorescence emission is significantly reduced when these single-stranded oligonucleotides hybridize to complementary single-strands that have one or more guanosine bases in the vicinity of the fluorophore (see e.g., Morrison et al. (1989) Anal Biochem 183:231-244; Seidel et al. (1996) J Phys Chem 100:5541-5553; Broude et al. (2001) Nucl Acids Res 29:No. 19 e92; Kurata et al. (2001) Nucl Acids Res 29:No. 6 e34). Also see the following U.S. Patents Livak et al. U.S. Pat. No. 5,723,591, Nardone et al. U.S. Pat No. 6,117,986, Livak et al. U.S. Pat No. 6,258,569, and Hawkins, U.S. Pat. No. 6,451,530. The reduction in fluorescence emission when the fluorophore is in close proximity to the guanosine bases is known as G-base quenching and has been described in detail in the scientific literature, see e.g. Torimura et al., (2001) Anal Sci 17:155-160; Zahavy and Fox (1999), J Phys Chem B 103:9321-9327; Crockett and Wittwer (2001), Anal Biochem 290:89-97. In this configuration ( FIG. 2A ), first strand 1 is base-paired to second strand 2 , and second strand 2 has a series of guanosine (G) bases 3 that are in close proximity to fluorophore 4 when strands 1 and 2 are base-paired. Similarly, fluorescence emission of a fluorophore can be quenched ( FIG. 2B ) if a single-stranded oligonucleotide forms a hairpin or stem-loop configuration 5 that brings fluorophore 6 attached to a base at one end of the strand into close proximity to guanosine bases 7 on the other end of the same strand, see e.g. Walter and Burke (1997) RNA 3:392-404. However, in the method of the invention ( FIG. 2C ), we have discovered that a reporter oligonucleotide 8 with an attached fluorophore 9 hybridized to a single-stranded oligonucleotide with the potential of forming a hairpin or stem-loop configuration 10 will have its fluorescence emission quenched if there are guanosine bases 11 in the vicinity of the fluorophore 9 when the structure is in the hairpin or stem-loop configuration 10 .
[0066] The invention allows an oligonucleotide sequence to be quickly and inexpensively labeled with a fluorophore, and obviates the need to chemically label a longer sequence with a fluorophore. Labeling of longer sequences is more difficult and requires more expensive and time-consuming purification procedures. Because the same 5′ tail sequence complementary to the reporter oligonucleotide can be added to each capture oligonucleotide, only a single fluorophore-labeled reporter oligonucleotide needs to be manufactured in order to detect tens of thousands of gene sequences in an array. The benefit of only labeling one nucleotide sequence with a fluorophore should be apparent Moreover, the attachment of the reporter oligonucleotide to the capture oligonucleotide, as was seen in the attachment of the capture oligonucleotide to the address sequence, is done through self-assembly, thus making the addition of a fluorophore to the capture oligonucleotide as simple as mixing the reporter and capture oligonucleotides together under conditions that allow hybridization.
[0067] In one mode of operating the present invention, the hairpin or stem-loop configuration 1 of capture oligonucleotide 2 is heated to a temperature that causes the secondary structure to linearize ( FIG. 3A ). When this occurs, the fluorophore 3 on the reporter oligonucleotide 4 is no longer in close proximity to the guanosine bases 5 , and thus its fluorescence is no longer quenched. If a nucleic acid strand like a mRNA 6 that bears a sequence complementary to the mRNA recognition sequence 7 in the capture oligonucleotide 2 is added to the heated capture oligonucleotide (in the open configuration), and then the system is allowed to cool, the mRNA 6 will hybridize with the capture oligonucleotide 2 thus preventing the formation of the hairpin or stem-loop 1 secondary structure ( FIG. 3B ). This prevents the quenching of the fluorophore 3 on the reporter oligonucleotide 4 . If on the other hand, the complementary mRNA sequence is not present in the test sample ( FIG. 3C ), the hairpin or stem-loop configuration 1 of the capture oligonucleotide 2 will reform upon cooling and the fluorophore 3 on the reporter oligonucleotide 4 will once again be in close proximity to the guanosine bases 5 on the capture oligonucleotide 2 , and thus its fluorescence will be quenched. Therefore, the presence of a target nucleic acid in a biological sample is indicated by an inhibition of fluorescence quenching.
[0068] A further advantage of the configuration is the ability to generate internal references of fluorescent intensity in order to mathematically estimate target nucleic acid concentrations. In the absence of target nucleic acid, fluorescent intensity can be measured with all hairpin or stem-loop structures in the quenched state by cooling, generating a closed-configuration reference signal. In the presence or absence of target nucleic acid, fluorescence intensity can be measured when all hairpin or stem-loop structures are in the open state by heating to a temperature that causes the secondary structure to linearize ( FIG. 3A ), generating an open-configuration reference signal. Either or both of these fluorescent intensities can be used as reference signals for comparison to determine the presence of target nucleic acid in a test sample. Fluorescent intensities approximately equal to the closed-configuration reference signal indicate the absence or very low concentrations of target nucleic acid. Increasing fluorescent intensities, approaching the open-configuration reference signal, indicate increasing concentrations of target nucleic acid.
[0069] Because a method of the invention detects and measures nucleic acid sequences using self-assembly through hybridization, one of the design considerations involves the temperature at which each set of hybridized oligonucleotides dissociates or melts (melting temperature or T m ). Although the specific sequence of bases in the address, hairpin, and reporter oligonucleotides can be varied, the mixture of A, T, C, and G bases may be preferred as it determines the temperature at which two base-paired strands dissociate or melt. In particular, T m of double stranded oligonucleotides is influenced by the relative numbers of G and C bases generally according to the formula T m =69° C.+0.41 (molar % G-C)-650/average length of probe. The dependence of T m of the stem region of the hairpin on the base sequence can be predicted from the free energy of formation of the stem hybrid calculated using DNA folding program such as the Zuker folding program. Although it is not necessary in a method of the invention to open the hairpin by heating before hybridization with target nucleic acid, the linearization of the hairpin by heating will facilitate hybridization with target. Therefore, it is preferred that the melting temperatures of the address oligonucleotide and reporter oligonucleotide to their respective complementary sequences in the capture oligonucleotide are higher than the temperature used to melt the hairpin. In addition, it is advantageous to have the melting temperature of the target nucleic acid strand with the nucleic acid recognition sequence higher than the melting temperature of the hairpin-forming sequence hybridized to the hairpin sequence. This facilitates the capture of the target nucleic acid by allowing it to hybridize to the target nucleic acid recognition sequence at a temperature that maintains the hairpin in the open configuration. Even a 10° C. difference in melting temperatures is more than sufficient to allow the melting of the hairpin structure without the release of the capture oligonucleotide from the address oligonucleotide or the release of the reporter oligonucleotide from its complementary sequence on the tail of the capture oligonucleotide. Techniques for thermocycling with precise temperature control are well known to those skilled in the art. Moreover, one skilled in the art through the use a variety of commercially available and free software programs for designing nucleotide probes can easily accomplish calculation of melting temperatures.
[0070] The present invention will be more clearly understood from the following specific examples. These examples are provided solely for illustrative purposes and should not be construed to limit the scope of the invention in any way.
EXAMPLES
[0071] To illustrate the operation of the present invention, several studies were performed in which a specific nucleic acid sequence was detected in solution using a hairpin capture oligonucleotide to which was attached a fluorophore-labeled reporter oligonucleotide. The nucleic acid sequences detected were all from the murine B7.2 gene; see GenBank BC613807, GI:15489434.
General Materials and Methods
[0072] The following oligonucleotides were custom synthesized by Integrated DNA Technologies, Inc. (IDT, Coralville, Iowa) or Synthetic Genetics, Inc. (San Diego, Calif.). The base sequences were designed with the aid of OligoAnalyzer 3.0 software from IDT to achieve specific melting temperatures, and to minimize the formation of self-dimers, unwanted hairpins, and cross-hybridization. Note that all sequences are given in the 5′->3′ orientation. One or more of the following oligonucleotides was used in the examples one through five:
[0073] Reporter Oligonucleotide (RO-TAMRA): TAMRA-AAAATCCACCCACCCCACCC (SEQ ID NO:1). This 5′-TAMRA-labeled oligonucleotide is complementary to the 5′ tail sequence of the capture oligonucleotide.
[0074] Reporter Complement (RC): GGGTGGGGTGGGTGGATTTT (SEQ ID NO:2). This oligonucleotide is complementary to the reporter oligonucleotide, and was used to determine if a G base five nucleotides away from the TAMRA fluorophore could cause quenching.
[0075] Capture Oligonucleotide (CO): GGGTGGGGTGGGTGGATTTTCCCAAACTTACGGATCGTGGGTGCTTCCGTAA GTTTGGGCCCCTCCTCCTCCCTCCTCC (SEQ ID NO:3). This 79-mer oligonucleotide has a short nucleotide sequence complementary to a sequence in the murine B7.2 mRNA.
[0076] Control Capture Oligonucleotide (CCO): GGGTGGGGTGGGTGGATTTTAAAAAACTTACGGATCGTGGGTGCTTCCGTAA GTTTTTTCCCCTCCTCCTCCCTOCTCC (SEQ ID NO:4). This oligonucleotide has the same sequence as the capture oligonucleotide except that three thymines replace three guanines at positions 23 to 25 (from the 5′ terminus).
[0077] 24mer Target Sequence (24mer): CCCAAACTTACGGAAGCACCCACG (SEQ ID NO:5). This oligonucleotide represents a target that is complementary to 24 nucleotides in the target recognition sequence in the CO and CCO.
[0078] B7-67mer Target Sequence (B7-67mer). CCAGAACTTACGGAAGCACCCACGATGGACCCCAGATGCACCATGGGCTTG GCAATCCTTATCTTG (SEQ ID NO:6). This oligonucleotide represents a segment of the murine B7.2 mRNA sequence. Its sequence is complementary to the 22 nucleotides in the mRNA recognition sequence.
[0079] Address Oligonucleotide with Disufide (AO/SS): 5′-disulfide-GGAGGAGGGAGGAGGAGGGG (SEQ ID NO:7). This oligonucleotide has a disulfide group at the 5′ end that enables its attachment to the substrate. Hybridization of the capture oligonucleotide to this address oligonucleotide results in the surface attachment of the capture sequence.
Preparation of Nucleic Acid Samples
[0080] The oligonucleotides were dissolved in TE buffer (Tris-EDTA buffer: 10 mM Tris-HCl, 1 mM EDTA, 1 M NaCl, ˜pH 7.7). The TE buffer solutions were prepared with doubly distilled water (Barnstead MegaPure 3 system) and filtered with a sterile, 0.2 μm nylon syringe filter (Nalgene™) before used.
Fluorescence Spectroscopy
[0081] All fluorescence spectra were collected with a Spex Fluorolog 3 fluorescence spectrometer (Instrument S.A., Inc., New Jersey). Both excitation and emission monochromators utilize double mechanically blazed planar gratings. Emissions from solutions in cuvettes were collected at 90° with respect to the incident light. The samples were excited at 555 nm and the emission spectra were collected in one single scan in the wavelength range of 570-675 nm (with an increment of 1 nm and integration time of 0.5 s).
[0082] Variable temperature experiments were performed using a single cell sample heater/cooler holder (model FL 1027, JY Inc., New Jersey). The temperature of the sample holder was varied by circulating water from a temperature-controlled water bath (Fisher Scientific Model #9150). After the desired temperature was attained, a cuvette containing the sample was placed in the jacketed sample holder and the solution was equilibrated for 5 minutes. Longer equilibration time was avoided to minimize evaporation of solvent. The difference in the actual sample temperature from the temperature readout of the circulator was calibrated as follows. After the desired temperature of the water circulator was attained, a TE buffer solution in a cuvette was placed in the sample holder to equilibrate for 5 minutes. The actual temperature of the buffer solution and the temperature of the circulating water in the circulator were measured using a thermometer and compared to the temperature read out of the circulating bath. The temperature values for all experiments described below were the corrected temperatures of the samples.
Example 1
Evidence for the Fluorescence Quenching of RO-TAMRA by G Bases on the Hairpin Loop of the Capture Oligonucleotide
[0083] To evaluate the effectiveness of the G-bases 1 (shown in FIG. 4B ) in the hairpin loop of CO 2 in quenching the emission of RO-TAMRA 3 , the changes in fluorescent emission of RO-TAMRA 3 upon hybridization with RC 4 ( FIG. 4A ), CO 2 ( FIG. 4B ), and CCO 5 ( FIG. 4C ), respectively, were compared. Three aliquots 1 - 3 (600 μL each) of a 1.5×10 −6 M solution of RO-TAMRA were prepared and their fluorescent emission spectra recorded. Small volumes of the solutions (˜8.8×10 −4 M in concentration) of RC (2 μL), CO (˜1.1 μL), and CCO (1 μL) were added to solutions 1-3, respectively. The fluorescent emission spectra of the resultant solutions were recorded at 25° C. To facilitate the comparison of the fluorescence intensities of different solutions, all emission spectra were normalized. The maximum emission intensity of each solution of RO-TAMRA before the addition of other oligonucleotides was considered as 100% ( FIG. 5 a ). The relative emission intensities of the solutions after the addition of RC, CO, or CCO with respect to the maximum emission intensity before the addition of RC, CO, or CCO were calculated.
[0084] As shown in FIG. 5 b , a small decrease (˜6%) in emission intensity of RO-TAMRA was observed upon hybridization with RC. This moderate quenching may have been due to the presence of a G base five nucleotides away from TAMRA, or perhaps due to the moderate quenching effects of other nucleotides in the RC sequence. On the other hand, a much larger decrease (˜40%) in emission intensity of RO-TAMRA was observed upon hybridization with CO in the hairpin-closed form ( FIG. 5 c ). These results strongly indicated that G bases on the hairpin loop segment of CO quenched TAMRA fluorescence. However, to verify the G base quenching, we designed CCO in which three G bases were replaced by three T bases 6 as shown in FIG. 4C . Hybridization of RO-TAMRA with CCO resulted in only about 6% fluorescence quenching of TAMRA ( FIG. 5 d ), similar in magnitude to the quenching by RC. This result indicated that the G bases on the closed hairpin loop that were in proximity to TAMRA mainly caused the large quenching effect of CO.
Example 2
Detection of 24mer Target Oligonucleotides by Hybridization with CO in the Hairpin-Opened Form
[0085] A 24-mer strand (24mer) complementary to the mRNA recognition sequence of the CO was used to demonstrate that the hybridization of target oligonucleotide 1 traps the CO 2 in the hairpin-opened form ( FIG. 6A ) and thus decreases the quenching of RO-TAMRA 3 by the G bases 4 in the hairpin section. Control experiments were performed using CCO 5 ( FIG. 6B ) instead of CO 2 .
[0086] The solutions listed in Table 1 were prepared. Solutions 6 and 8 were heated to 76° C. for 10 min to open the hairpins and then cooled to 25° C. to allow hybridization with the target 24mer. After the fluorescent emissions from solutions 1-4 were recorded, 2-μL aliquots of solutions 5-8 were added to solutions 1-4 respectively to give solutions 1a-4a. The fluorescence emissions from solutions 1a-4a were then recorded. The maximum emission intensity of the solutions 1-4 before the addition of other oligonucleotides was considered as 100 ( FIG. 7 a ). The relative emission intensities of the solutions 1a-4a with respect to the maximum emission intensity before the addition of RC, CO, or CCO were calculated.
[0000]
TABLE 1
Solutions used for studying the effect of target 24mer
on the emission intensity of the RO-CO hybrid
Composition
Solution #
RO
CO
CCO
24mer
1-4 (600 μL
1.5 × 10 −8 M
0
0
0
each)
5
0
9.7 × 10 −6 M
0
0
6
0
4.9 × 10 −6 M
0
1.0 × 10 −3 M
7
0
0
9.7 × 10 −6 M
0
8
0
0
4.9 × 10 −6 M
1.0 × 10 −3 M
1a (2 μL of
1.5 × 10 −8 M
3.2 × 10 −8 M
0
0
5 added to 1)
2a (2 μL of
1.5 × 10 −8 M
1.6 × 10 −8 M
0
3.3 × 10 −6 M
6 added to 2)
3a (2 μL of
1.5 × 10 −8 M
0
3.2 × 10 −8 M
0
7 added to 3)
4a (2 μL of
1.5 × 10 −8 M
0
1.6 × 10 −8 M
3.3 × 10 −6 M
8 added to 4)
[0087] As shown in FIG. 7 and Table 2, the hybridization of CO in the closed hairpin form to RO-TAMRA led to significant quenching (˜25%) of the TAMRA emission by the G bases in the hairpin section of the CO ( FIG. 7 b ). Prehybridization of the target 24mer with CO trapped the hairpin in the open form. As a consequence, the hybridization of this opened hairpin with RO-TAMRA resulted in a much weaker quenching (˜13%) of the TAMRA emission ( FIG. 7 c ). As expected, the intensity of emission from the hairpin-opened RO-TAMRA-CO-24mer hybrid ( FIG. 7 c ) was similar to the emissions from the RO-TAMRA-CCO hybrid ( FIG. 7 d ) and the RO-TAMRA-CCO-24mer hybrid ( FIG. 7 e ) since all three hybrids were only quenched by the G-bases in the sequence complementary to RO-TAMRA. It should be noted that in the absence of CO or CCO, the addition of excess 24mer to RO did not cause observable change in the fluorescent emission of TAMRA. This result confirmed that there was no direct influence of 24mer on the fluorescent emission of RO.
[0000]
TABLE 2
Summary of the studies on the effect of target 24mer on
the emission intensities of the RO-CO and RO-CCO hybrids
Percent Decrease in
Solution
Emission Intensity (%)
1 (RO only)
0%
1a (RO + CO)
25%
2 (RO only)
0%
2a (RO + CO + 24mer)
13%
3 (RO only)
0%
3a (RO + CCO)
12%
4 (RO only)
0%
4a (RO + CCO + 24mer)
10%
RO + 24mer
0%
Example 3
Detection of 24mer Target Oligonucleotides by Hybridization with CO Without Preheating CO to the Hairpin Opened Form
[0088] This example illustrates an alternative procedure for detecting target nucleic acid without preheating the capture oligonucleotide to the hairpin opened form and prehybridization of the target with the hairpin opened capture oligonucleotide. In this example, 600-μL of a ˜1.7×10 −7 M solution of RO-TAMRA was prepared and the fluorescent emission spectrum of the solution was recorded ( FIG. 8 a ). Small volumes of a solution (˜1.0×10 −4 M in concentration) of CO were added to the solution of RO-TAMRA until no further decreased in fluorescence intensity of the solution was observed. A small volume (3 μL) of a solution (˜9.2×10 −5 M) of target 24mer was then added and allowed to hybridize with the RO-CO hybrid. The concentrations RO-TAMRA, CO, and 24mer target in the resultant solution were approximately 1.7×10 −7 M, 3.4×10 −7 M, and 4.6×10 −7 M, respectively. The change in fluorescence intensity was monitored. As shown in FIG. 8 and Table 3, after the addition of 2 μL of CO to hybridized RO-TAMRA, a large decrease (˜45%) in emission intensity of RO-TAMRA was observed ( FIG. 8 b ). Hybridization of 24mer with RO-CO trapped the capture oligonucleotide in the hairpin-opened form, and thus reduced the quenching of TAMRA emission and resulted in an increase in emission intensity by ˜30% ( FIG. 8 c ).
[0000]
TABLE 3
Summary of the effect of target 24mer on the
emission intensities of the RO-CO hybrids
Percent Decrease in
Solution
Emission Intensity (%)
RO only
0%
RO + CO
~45%
RO + CO + 24mer
~15%
Example 4
Detection of B7-67mer Target Oligonucleotides by Hybridization with CO in the Hairpin-Opened Form
[0089] In this example, 600-μL of a 1.7×10 −7 M solution of RO-TAMRA was prepared and the fluorescent emission spectrum of the solution was recorded ( FIG. 9 a ). Small volumes of a solution (1.0×10 −4 M in concentration) of CO were added to the solution of RO-TAMRA until no further decreased in fluorescence intensity of the solution was observed. A small volume (3 μL) of a solution (9.2×10 −5 M) of target B7-67 mer was then added and allowed to hybridize with the RO-CO hybrid. The change in fluorescence intensity was monitored. As shown in FIG. 9 and Table 4, after the addition of 2 μL of CO to hybridized RO-TAMRA, a large decrease (˜45%) in emission intensity of RO-TAMRA was observed ( FIG. 9 b ). Hybridization of B7-67mer with RO-CO trapped the capture oligonucleotide in the hairpin-opened form, and thus reduced the quenching of TAMRA emission and resulted in an increase in emission intensity by ˜10% ( FIG. 9 c ). No change in emission intensity of TAMRA was observed when B7-67mer was added to a solution of RO-TAMRA in the absence of CO. This confirms that there was no direct influence of B7-67mer on the fluorescent emission of RO-TAMRA (Table 4).
[0000]
TABLE 4
Summary of the effect of target B7-67mer on the
emission intensities of the RO-CO hybrids.
Percent Decrease in
Solution
Emission Intensity (%)
RO only
0%
RO + CO
~45%
RO + CO + B7-24mer
~35%
Example 5
Effect of AO-SS on the Emission Intensities of the RO-TAMRA-CO and RO-TAMRA-CCO Hybrids
[0090] Further quenching of TAMRA in RO-TAMRA-CO by hybridization with an address oligonucleotide that is rich in G bases at the 3′ end could maximize the difference in emission intensity between the hairpin-closed form and the opened form upon hybridization with target strand. In this example, solutions of RO-TAMRA (1.7×10 −7 M) hybridized with CO (2.0×10 −7 M) or CCO (2.0×10 −7 M) in TE buffer were prepared. The fluorescence emission spectra of these solutions containing the RO-CO and RO-CCO were shown in FIGS. 9 a and 9 b , respectively. To each solution was then added 1.2 uL of a 1.0×10 −3 M solution of AO-SS. The concentration of AO-SS in the resultant solutions was ˜2.0×10 −6 M. As shown in FIG. 10 and Table 5, the hybridization of the RO-TAMRA-CO hybrid with AO-SS decreased the fluorescent emission of RO-CO by about 14% ( FIG. 10 c ). Since the spatial separation of the G bases at the 3′ end of AO-SS from TAMRA in the RO-TAMRA-CCO hybrid should be similar to that in the RO-TAMRA-CO hybrid, similar quenching effect of AO-SS on the emission from RO-TAMRA-CCO was observed ( FIG. 10 d ). In the absence of a capture oligonucleotide, the addition of excess AO-SS to RO-TAMRA did not cause any observable change in the fluorescent emission of TAMRA. This confirms that there was no direct quenching of RO-TAMRA emission by AO-SS when they were separated in solution.
[0000]
TABLE 5
Summary of the effect of AO-SS on the emission intensities
of the RO- TAMRA- CO and RO-TAMRA- CCO hybrids
Percent Decrease in
Solution
Emission Intensity (%)
RO-TAMRA -CO + AO-SS
~14%
RO-TAMRA -CCO + AO-SS
~12%
Example 6
A Single Base Change in a 15-mer-Target Sequence can be Detected
[0091] The experiment described in this example was performed with a slightly modified technique. Here, 4 mL of a 1.0×10 −8 M solution of RO-TAMRA in TE buffer was prepared. The solution was heated to 76° C. and then cooled to 18° C. using a temperature-controlled circulating water bath (Fisher Scientific model 9105). The temperature of the solution was monitored using a digital device (Omega Digicator model 410B-THC-C) equipped with a probe (Model LN2002 702A) that was inserted into the solution. Fluorescence emission spectra of the solution were recorded upon every two-degree decrease in temperature until a temperature of 18° C. was reached. Emission intensities were calculated with respective the emission of the RO-TAMRA solution at 18° C. The sequences of the nucleotides used in this example are provided in Table 6.
[0000]
TABLE 6
Nucleotide sequences used in Example 6
RO-TAMRA
5′-TAMRA-linker-AAA ATA ACC ACC CAC CCA
CCC
CO
GGG TGG GTG GGT GGT TAT TTT CCC TTA CAT
CGT GGG TGC TTC CGT AAG GGT GGG AGG GAG
GGA GGG AGA G
(SEQ ID NO: 8)
B7-67mer
CCA GAA CTT ACG GAA GCA CCC ACG ATG GAC
CCC AGA TGC ACC ATG GGC TTG GCA ATC CTT
ATC TTT G
(SEQ ID NO: 9)
T3
GGA AGC ACC CAC GAT
(SEQ ID NO: 10)
SM
GGA AGA ACC CAC GAT
(SEQ ID NO: 11)
[0092] FIG. 11 shows that the emission intensity of RO-TAMRA increased with decreasing temperature because of reduced non-radiative decay. To demonstrate that a single base mismatch in a 15mer sequence complementary to a sequence in the loop of CO can be detected, a few μL of a 10 −5 M solution of T3 or SM was added to a solution of the self assembled CO+RO-TAMRA (10 −8 M) prepared as described above. The emission spectra of the solutions were monitored when the solutions were cooled from 76° C. The relative emission intensities of the solutions with respect to the maximum emission intensity of RO-TAMRA at 18° C. were calculated. The sequence of T3 is complementary to the CO loop region only and has a melting temperature of ˜60° C. SM differs from T3 in only one base at position 6. The presence of one mole equivalence of T3 trapped RO-TAMRA+CO in the hairpin opened form and increased the emission intensity to ˜80% at 18° C. Compared to T3, SM binds to TAMRA+CO at a lower temperature and is less effective in keeping RO-TAMRA+CO in the hairpin-opened form. Consequently, the emission profile of the RO-TAMRA+CO+SM hybrid differed significantly from that of RO-TAMRA+CO+T3 and less intense TAMRA emission was observed for RO-TAMRA+CO+SM at 18° C.
[0093] As summarized in Table 7, the emission intensity of RO-TAMRA+CO at 18° C. was 48% of the value obtained with RO-TAMRA alone (this value was normalized to 100%). CO+RO-TAMRA was prepared by adding a few μL of a concentrated solution (10 −5 M) of CO to the solution of RO-TAMRA (10 −8 M) to give one mole-equivalence of CO with respect to RO-TAMRA. The resultant solution was heated to 76° C. and then cooled to 18° C. Emission spectra of the solution were recorded upon every two-degree decrease in temperature until a temperature of 18° C. was reached. B7-67mer added before cooling maintained the stem-loop in the open configuration and gave an emission intensity of 88%. As expected, when T3 was added the smaller 15mer was slightly less effective at keeping the stem-loop in the open configuration (emission intensity of 82% at 18° C.). However, when SM was added, the emission intensity at 18° C. was only 70%, indicating that only a single base mismatch with the complementary sequence in CO can be detected. In a microarray application, this allows sequences differing in only a single base to be identified, and would forestall cross reactivities between similar nucleotide sequences, a major problem with current gene microarrays. It can also be used for the analysis of point mutations in gene sequences.
[0000]
TABLE 7
A single base change in a 15mer target sequence can
be detected as a change in emission intensity
Normalized Emission Intensity
Solution
at 18° C. (%)
RO-TAMRA
100
RO-TAMRA + CO (1.0 equiv.)
48
RO-TAMRA + CO + B7-67mer
88
RO-TAMRA + CO + T3
82
RO-TAMRA + CO + SM
70 | The invention provides novel oligonucleotides and methods of using the same for detection or measurement of specific nucleic acid molecules. The invention also features nucleic acid arrays comprising the oligonucleotides of the invention. An oligonucleotide of the invention comprises (1) a reporter-binding sequence capable of hybridizing to a fluorrophore-labeled reporter sequence and (2) a hairpin-forming sequence capable of forming a stem-loop. Formation of the stem-loop modifies (e.g., quenching) the fluorescence signals of the reporter sequence when the reporter sequence is hybridized to the oligonucleotide. This can be achieved, for example, by bringing one or more guanine based in the oligonucleotide into close proximity to the fluorophore(s) of the reporter sequence by virtue of the formation of the stem-loop. Disruption of the stem-loop, such as by hybridization of a target sequence to at least part of the hairpin-forming sequence, produces a detectable change in the fluorescence signals. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
This application is a divisional application of U.S. application Ser. No. 14/089,041 filed on Nov. 25, 2013, now U.S. Pat. No. 9,077,139, which is a divisional application of U.S. application Ser. No. 13/442,425 filed on Apr. 9, 2012, now U.S. Pat. No. 8,826,582 issued on Sep. 9, 2014, which claims the benefit of priority to U.S. Provisional Application 61/629,737 filed Nov. 26, 2011.
FIELD OF INVENTION
This invention relates to precision pointing, in particular to devices, apparatus, systems and methods for providing accurate linear and angular positioning of a payload, such as a laser pointer and maintains the initial precise pointing during and after exposure in high G shock and vibration environments, with the capability of adjusting minute changes in beam orientation, where the beam supporting the payload can be a cantilevered conical shaped beam or cantilevered S shaped beam or a center deflecting beam with freely movable ends. The precision adjustments can be performed in a zero G, one G, or high G environment and maintains the adjustment during and after being exposed to a high G shock or vibration environment.
BACKGROUND AND PRIOR ART
Laser pointing devices have been widely used on firearms to allow the shooter to accurately aim the weapon without using the weapons sights, and are used in military type training systems to simulate an aimed shot. They have also been used in many commercial products and as aids in testing products, also range finders, laser designators, and the like.
The most common firearm application is to mount a laser on a weapon, providing adjustment so the laser can be aligned with the sights and use the laser beam to point the weapon at a target while the trigger is being pulled. Once the shot is fired, the alignment of the laser relative to the sights does not come into play since the bullet is on its trajectory to the target. The patents also claim the mounting and adjustments isolates the laser from the weapons shock which means the laser assembly is designed to move relative to the weapon during the high G shock event from firing the weapon.
The Multiple Integrated Laser Engagement System (MILES) is a training system providing a realistic battlefield environment for soldiers involved in training exercises. The Army developed the original family of MILES devices in the late '70s and early '80s using state-of-the-art technology of that time. MILES is the primary training device for force-on-force training at Army home stations. A MILES system for a soldier includes a laser module (Small Arms Transmitter or SAT) mounted to the barrel of a real weapon, a blank firing adapter, and an integrated receiver with sensors on the helmet and load-bearing vests for the soldiers. The SAT's laser beam is aligned by the solder to the weapon's sights when the SAT is mounted to the weapon. During the training exercise, the soldier aims the weapon on the opposing force soldier using the weapon's standard sights. When a blank shot is fired by the weapon, it causes the laser to fire a coded laser burst in the direction the weapon was aimed. Information contained in the laser pulses includes the player ID and the type of weapon used. If that laser burst is sensed by the receiver of another soldier, the “hit” soldier's gear beacon makes a beeping noise to let them know they are “dead.”
When the weapon fires a blank in the MILES system, unique shock, flash and acoustic signatures are generated. Two of these signatures are decoded to determine a valid event and initiate MILES code transmissions Once a validated event is detected, the transmitter fires 4 Hit Words and 128 Near-Miss Words. Each word is ˜4 milliseconds (msec) long, the duration for 132 words is 484 msec or 0.484 seconds. The laser beam foot print (typical angular foot print size is 1 mrad to 3 mard and the maximum size is limited by the specification) needs to illuminate the detector sensor for the full duration of a Hit or Near-Miss Word to be registered by the receiver software as a Kill or Near-Miss.
In the MILES system, there occurs a gross angular weapon movement after the blank has fired that moves the center of the laser foot print away from the sensor. During the time period from trigger pull to firing of the blank and firing the laser, the weapon moves in a semi-repeatable motion. See U.S. Published Patent Application 2004/0005531 for FIGS. 8, 9 & 10. For open bolt weapons like the M240 and M249, the movement and corresponding error is greater after the trigger pull due to the time required for the bolt to close and the impact of the bolt increases the gross angular weapon movement. The shock from the bolt closing and/or the blank firing causes the SAT housing and mounting components to flex and introduce an addition pointing error to the gross weapon movement error which is not repeatable. Also based on the internal construction, the adjustment mechanism can unload (bounce) during the high G event and introduce additional significant pointing errors which is not repeatable.
The sum of these angular pointing errors sources, (gross weapon movement, SAT component flexure and unloading) start at zero values for time zero (trigger pull) and increase over time. The SAT laser needs to be pointing at the opposing soldier's receiver and illuminating it for the 4 msec duration required to transmit the first hit word. The total angular pointing error movement has to less than half the laser angular footprint by the time the SAT has detected the event and finished transmitting the first hit word. The gross weapon angular pointing error is real and part of the normal system operation. The second and third error sources (flexure and unloading) are the problems. They are not part of the normal system operation and need to be minimized or cancelled. To the extent these are not reduced, the training system will depart from reflecting the actual accuracy of the soldier's performance, failing to register otherwise good hits.
The present SAT design approaches do not maintain the initial precise pointing during and after exposure in high G shock and vibration environments.
Various approaches have been proposed to deal with these types of problems. For example, U.S. Published Patent Application 2004/0005531 to Varshneya et al. describes an elaborate and complex system for calibrating misalignment of a weapon-mounted zeroed small arms transmitter (ZSAT) laser beam axis with the shooter line-of-sight (LOS) in a weapon training system, but fails to easily solve the problem. The proposed solution only addresses the repeatable error produced by the dynamic muzzle displacement from the gross weapon movement not the unrepeatable errors from the flexure and unloading errors.
Other types of devices have resulted in additional problems. See for example, U.S. Pat. No. 2,189,766 to Unerti; U.S. Pat. No. 3,476,349 to Smith; U.S. Pat. No. 3,596,863 to Kaspareck; U.S. Pat. No. 4,079,534 to Snyder; U.S. Pat. No. 4,161,076 to Snyder; U.S. Pat. No. 4,212,109 to Snyder; U.S. Pat. No. 4,295,289 to Snyder; U.S. Pat. No. 4,313,272 to Matthews; U.S. Pat. No. 4,686,440 to Nagasawa; U.S. Pat. No. 4,738,044 to Osterhout; U.S. Pat. No. 4,876,816 to Triplett; U.S. Pat. No. 4,916,713 to Gerber; U.S. Pat. No. 4,958,794 to Brewer; U.S. Pat. No. 5,033,219 to Johnson; U.S. Pat. No. 5,299,375 to Heinz; U.S. Pat. No. 6,378,237 to Matthews; U.S. Pat. No. 6,714,564 to Meyers; U.S. Pat. No. 6,793,494 to Deepak; U.S. Pat. No. 6,887,079 to Robertsson; U.S. Pat. No. 7,014,369 to Alcock; U.S. Pat. No. 7,331,137 to Hsu; U.S. Pat. No. 7,418,894 to Ushiwata; U.S. Pat. No. 7,558,168 to Chen; U.S. Pat. No. 7,726,061 to Thummel; U.S. Pat. No. 7,753,549 to Solinsky; U.S. Pat. No. 7,886,644 to Ushiwata; U.S. Pat. No. 7,922,491 to Jones; U.S. Pat. No. 7,926,218 to Matthews; and U.S. Published Patent Application 2001/0000130 to Aoki; 2003/0204959 to Hall; 2004/0161197 to Pelletier; 2006/0156556 to Nesch; and 2007/0240355 to Hsu.
Some of the proposed devices intentionally shock isolate by allowing movement of the laser beam axis relative to the weapon to prevent damage to the laser or associated electronics and therefore does not maintain alignment during the shock.
Other proposed devices include multiple parts that move relative to each other when the devices are aligned or boresighted. Due to manufacturing tolerances, there are clearances between mating surfaces that slide relative or mate to each other. There is friction at the sliding and spherical joints due to the preload forces. The tangential friction forces at the contacting surfaces produce bending in the components. During the high G shock or vibration event, the friction at the interface surfaces will go to zero and allow the components to slide and rotate to a force free state. This movement will produce a pointing error relative to the initial alignment. The larger the quality of interfaces, the larger the total pointing error after a shock.
Additional problems with the prior art have included devices having sliding or pivoting joints and geared interfaces that have clearance between the none contacting surfaces can become contaminated which will cause binding or increased friction which will increase the pointing angle error.
Prior art devices have included plural components, threaded rods that translate wedges used for alignment, due to clearances between the mating threaded parts, when the direction and adjustment is reversed, hysteresis will be introduced which is a source of error. After adjustment, during the shock, the stiction will be relieved and the wedge can move over the range of the thread clearance producing a pointing error.
Some of the prior art devices include large and heavy components for a 1 G or manufacturing environment where there is no shock or vibration environment and there is no limitation on size, weight or adjustment type and are cumbersome for field use, difficult to adjust in the field, or the alignment is set at the factory.
Some of the prior art includes devices which cannot maintain alignment or boresight over the wide temperature operating range from the low −40° C. to the high temperature where the barrel of the M240 can exceed 350° C. Over this temperature range, any mismatch in the components CTE (coefficient of thermal expansion) will cause binding or increased clearances at the interfaces which will increase the pointing errors. The component's CTE mismatch will also introduce a bimetallic error as the temperature changes from the initial adjustment temperature.
Still other prior art devices use different types of springs to preload the system against the adjustment stops so a payload does not move away from the stop and produce a dynamic pointing error. The springs used cannot produce enough force in the limited volume to counteract the unloading force.
Thus, the need exists for solutions to the above problems with the prior art.
SUMMARY OF THE INVENTION
A primary objective of the present invention is for providing compact devices, apparatus, systems and methods for maintaining accurate linear and angular positioning of a conical shaped cantilevered beam or S shaped cantilevered beam or center deflecting beam with free ends, with each beam having one end with mounted payload, during and after exposure in high G shock and vibration environments, with the capability of adjusting minute changes in beam orientation.
A secondary objective of the present invention is for providing compact devices, apparatus, systems and methods which maintains the initial precise pointing during and after exposure in high G shock and vibration environments, and does not require joints which have errors.
A third objective of the present invention is for providing compact devices, apparatus, systems and methods which maintains the initial precise pointing during and after exposure in high G shock and vibration environments, that does not have any static friction (stiction) introduced deflections where the tangential friction forces at the contacting surfaces cause bending deflections of the mechanism's components when boresighted.
A fourth objective of the present invention is for providing compact devices, apparatus, systems and methods which maintains the initial precise pointing during and after exposure in high G shock and vibration environments, which does not allow contamination to occurs between any bearing or mating surfaces.
A fifth objective of the present invention is for providing compact devices, apparatus, systems and methods which maintains the initial precise pointing during and after exposure in high G shock and vibration environments, having a single element with no hysteresis, a non-reversing adjustment load and is kinematically stable.
A sixth objective of the present invention is for providing compact devices, apparatus, systems and methods which maintains the initial precise pointing during and after exposure in high G shock and vibration environments, which is small, and light weight-by combining functions where the mass is reduced and the restraining force required and the associated mass is also reduced.
A seventh objective of the present invention is for providing compact devices, apparatus, systems and methods which maintains the initial precise pointing during and after exposure in high G shock and vibration environments, that does not show any pointing error over a wide temperature range, from −40° C. to approximately 350° C., and more.
An eighth objective of the present invention is for providing compact devices, apparatus, systems and methods which maintains the initial precise pointing during and after exposure in high G shock and vibration environments that is immune from binding at the joints and pointing errors due to any CTE mismatch of the components.
A ninth objective of the present invention is for providing compact devices, apparatus, systems and methods which maintains the initial precise pointing during and after exposure in high G shock and vibration environments, having an adjustment point location that can cancel/reduce the dynamic pointing error introduced by the beams first and second modes of vibrations which are the major contributors to the dynamic pointing errors.
A preferred embodiment of the precision pointing mechanism can include five major components or assemblies. The first component is the base which supports the other components. The second component is the payload which is being positioned and/or pointed. The third component is the conical element that connects to the base and provides linear and/or angular flexure between the payload and the base. The conical element also provides preload force against the adjustment element(s) which are the fourth and fifth components. The fourth and fifth components are the adjustment element(s) that provide displacement of the payload end of the conical element relative to the base. The conical element performs multiple functions; is the structural member attaches the payload to the base, provides the kinematic rotation and linear displacement of the payload and the preload force so the payload does not unload (move away) from the adjustment points during the high G event.
The novel configuration for precision pointing of payloads can include multiple parts that move relative to each other. Given the manufacturing tolerances, there are no clearances between the mating surfaces that can introduce pointing errors after the initial adjustment and allows movement during the high G shock and vibration events that can produce a dynamic pointing error and does not maintain the initial adjustment. Also, stiction between the components can introduce static and dynamic pointing errors. There is no stiction between the components that will be removed during the dynamic environment and allow the components to move relative to each other and produce a static and or dynamic pointing error.
Further objects and advantages of this invention will be apparent from the following detailed description of the presently preferred embodiments which are illustrated schematically in the accompanying drawings.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a perspective upper left front view of a single laser system with conical cantilevered beam supporting a laser.
FIG. 2 is a perspective upper right front view of the laser system of FIG. 1 .
FIG. 3 is a front view of the laser system of FIG. 1 .
FIG. 4 is a rear view of the laser system of FIG. 1 .
FIG. 5 is a right side view of the laser system of FIG. 1 .
FIG. 6 is a left side view of the laser system of FIG. 1 .
FIG. 7 is a cross-sectional view of the laser system of FIG. 6 along arrow 7 B
FIG. 8 is an exploded view of the laser system of FIG. 1 .
FIG. 9 is an upper front right perspective view of a housing the laser system of the previous figures mounted to a firearm.
FIG. 10 is a lower front right perspective view of the firearm mounted housing and laser system of FIG. 9 .
FIG. 11 is a top view of the firearm mounted housing and laser system of FIG. 9 .
FIG. 12 is an exploded view of the firearm mounted housing and laser system of FIG. 9 .
FIG. 13 is a perspective view of a dual laser or laser & detector system.
FIG. 14 is a perspective view of a mirror payload system.
FIG. 15 is an upper front left perspective view of another single laser system with an S shaped cantilevered beam supporting the laser.
FIG. 16 is an upper front right perspective view of the another single laser system with an S shaped cantilevered beam supporting the laser of FIG. 15 .
FIG. 17 is a top view of the laser system with S shaped cantilevered beam of FIG. 15 .
FIG. 18 is a front view of the laser system with S shaped cantilevered beam of FIG. 15 .
FIG. 19 is a right side view of the system with S shaped cantilevered beam of FIG. 15 .
FIG. 20 is a left side view of the laser system with S shaped cantilevered beam of FIG. 15 .
FIG. 21 is a rear view of the laser system with S shaped cantilevered beam of FIG. 15 .
FIG. 22 is an exploded view of the system with S shaped cantilevered beam of FIG. 15 .
FIG. 23 is an upper front right perspective view of another single laser system with a center deflecting beam supporting the laser.
FIG. 24 is an upper front left perspective view of the center deflecting beam supporting the laser of FIG. 23 .
FIG. 25 is a top view of the center deflecting beam supporting the laser of FIG. 23 .
FIG. 26 is a front view of the center deflecting beam supporting the laser of FIG. 23 .
FIG. 27 is a left side view of the center deflecting beam supporting the laser of FIG. 23 .
FIG. 28 is a right side view of the center deflecting beam supporting the laser of FIG. 23 .
FIG. 29 is a rear view of the center deflecting beam supporting the laser of FIG. 23 .
FIG. 30 is a cross-sectional view of the center deflecting beam supporting the laser along arrow 30 X of FIG. 25 with the beam in a non-deflected state and boresight pointed down
FIG. 31 is another cross-sectional view of the center deflecting beam supporting the laser module of FIG. 30 with the beam deflected down and boresight pointed straight ahead.
FIG. 32 is another cross-sectional view of the center deflecting beam supporting the laser module of FIG. 30 with the beam deflected down and boresight pointed partially down.
FIG. 33 is another cross-sectional view of the center deflecting beam supporting the laser module of FIG. 30 with the beam deflected fully down and boresight pointed up.
FIG. 34 is a graph showing the relationship between the preload forces over adjustment angle verses the peak forces due to the acceleration.
FIG. 35 shows the vertical pointing angle for unloading condition with the mill radians (mrad) pointing error in one axis for a system that unloads during the shock event.
FIG. 36 shows the pointing angle for correct preload condition with the mrad pointing error in one axis for a system that does not unload during the shock event.
FIG. 37 shows the pointing angle metric verses adjustment point location.
FIG. 38 is a perspective view of a cam version of the invention.
FIG. 39 is another perspective view of the cam version of FIG. 38 .
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Before explaining the disclosed embodiments of the present invention in detail it is to be understood that the invention is not limited in its applications to the details of the particular arrangements shown since the invention is capable of other embodiments. Also, the terminology used herein is for the purpose of description and not of limitation.
A listing of components will now be described.
1 . laser system with conical cantilevered beam 10 . base of housing 20 . rear wall of housing 25 . threaded opening for battery 30 . support housing portions for adjustment controls 32 . front top of housing 33 . cover of housing 34 . front side of housing 38 . front wall of housing 39 . cover mounting screws/washer 40 . cantilevered conical beam 42 . base wide end 43 . fastener (nut) 48 . narrow tip end 50 . payload 52 . laser housing 53 . laser diode 56 . lens 60 . lateral adjustment control 61 . o-ring for lateral adjustment 70 . vertical adjustment control 71 o-ring for vertical adjustment 80 . battery 85 . battery cover 87 . connector 90 . Circuit Card Assembly 92 . event sensor #1 94 . event sensor #2 96 . antenna cover 98 . on/off switch 100 . Firearm mounted application 110 . upper clamp 120 . pivotal clamp 123 . hinge pin 125 . screw/washer 190 weapon 200 . dual laser or laser and detector system 220 . dual laser or laser and detector payload 250 . single mirror system 270 . single mirror payload 300 . laser system with S shaped cantilevered beam 340 . S shaped cantilevered beam 342 . tip end of cantilevered beam 348 . rear mounted end of S shaped cantilevered beam 400 . laser system with center deflecting beam 420 . rear wall of housing 425 . opening in rear wall with opening having curved interior surface portion(s) 430 . front wall of housing 435 . opening in front wall with opening curved interior surface 440 . center deflecting beam 442 . rear conical portion of center deflecting beam 445 . middle portion of center deflecting beam 448 . front conical portion of center deflecting beam 450 payload (laser) support housing on front end of center deflecting beam 460 . rear mount support on rear end of center deflecting beam 470 . C shaped housing support for vertical and lateral controls 500 . Cam embodiment 510 . Cam wheel 520 . Cam wheel
Conical Shaped Cantilevered Beam
FIG. 1 is a perspective upper left front view of a single laser system 1 . FIG. 2 is a perspective upper right front view of the laser system 1 of FIG. 1 . FIG. 3 is a front view of the laser system 1 of FIG. 1 . FIG. 4 is a rear view of the laser system 1 of FIG. 1 . FIG. 5 is a right side view of the laser system 1 of FIG. 1 . FIG. 6 is a left side view of the laser system 1 of FIG. 1 . FIG. 7 is a cross-sectional view of the laser system 1 of FIG. 6 along arrow 7 B. FIG. 8 is an exploded view of the laser system 1 of FIG. 1 .
Referring to FIGS. 1-8 , the laser system can include basic components of an outer one-piece type housing to support the main components. The main components can include base 10 , with a rear solid wall 20 , and a support housing portions 30 for adjustment controls 60 , 70 , where the support portions can have an inverted C shaped configuration. A cantilevered conical beam 40 can have a wide base end 42 that can be mounted in the rear wall 20 by a fastener (nut) 43 at attaches about threaded ends of the wide base end 42 . Other types of mounting techniques can also be used The conical shaped beam can be hollow or solid. A narrow tip end 48 of the cantilevered beam 40 can pass through the middle of the C shaped support portions 30 and the narrow tip end 48 can be mounted to a payload 50 that can include a laser housing 52 with laser diode 53 and lens 56 .
The profile of the conical element's effective length can be a straight cylinder but the conical or curved shape provides lower weight and reduced dynamic pointing error. The taper adds to the capacity of the conical element by increasing the area moment of inertia where the moments and stresses are largest at the fixed end and allows material to be removed at the simply support end where the moments and stresses are minimal. The taper also provides a more constant curvature of the conical elements' centerline for a given deflection at the simply supported end.
The profile of the conical element's effective length can be a straight cylinder but the conical or curved shape provides lower weight and reduced dynamic pointing error. The taper adds to the capacity of the conical element by increasing the area moment of inertia where the moments and stresses are largest at the fixed end and allows material to be removed at the simply support end where the moments and stresses are minimal. The taper also provides a more constant curvature of the conical elements' centerline for a given deflection at the simply supported end.
The conical element's spring constant and deflection shape (slope) vs. displacement distance by the adjustment elements in each axis can be tailored by the type of material (metal, plastic, composite), effective conical element length, cross section shape and conical element profile. The effective spring constant of the system can also be adjusted by the stiffness of the conical element's mounting surface geometry on the base and the mounting interface geometry on the payload housing.
The conical element's coefficient of thermal expansion (CTE) can be adjusted to match the effective CTE of the base and the structure the base is mounted to. Damping material can also be incorporated in the conical element design to dampen the movement and associated pointing error over time.
The position of the outer end 48 of the cantilevered beam 40 can be adjustably positioned by both a lateral adjustment control 60 and vertical adjustment control 70 . The adjustment controls can be rotatable knobs, screws, and the like.
FIG. 9 is an upper front right perspective view of a housing 100 using the laser system 1 of the previous figures mounted to a firearm, such as a rifle barrel 190 . FIG. 10 is a lower front right perspective view of the firearm 190 mounted housing 100 and laser system 1 of FIG. 9 . FIG. 11 is a top view of the firearm 190 mounted housing 100 and laser system 1 of FIG. 9 . FIG. 12 is an exploded view of the firearm 190 mounted housing 100 and laser system 1 of FIG. 9 .
Referring to FIGS. 1-12 the laser system 1 can be mounted to a firearm 190 such as to a rifle barrel 190 . The rear end 42 of the conical beam 40 can be mounted through the rear wall 20 with the laser housing 50 attached as a payload to the tip end 48 of the cantilevered beam 40 . A SAT (small arms transmitter) cover 33 can be placed over an upper opening of a box shaped housing where vertical adjustment control 70 can threadably attach and pass through an opening in the front top 32 of housing, and a lateral adjustment control 60 can threadably attach and pass through an opening in the front side 34 of the housing. Laser tube housing 52 with rear mounted diode 53 and front mounted lens 56 can pass through a front opening in the front wall 38 of the housing. An antenna cover 96 can be mounted to the cover 33 , and the laser diode 53 can be controlled by on/off switch 98 which can be powered by battery 80 .
CCA is a Circuit Card Assembly, it contains the electronic components that runs the SAT, handles power management, has a processor that runs the software, signal conditions the output of the sensors, tells the laser diode to fire, contains an antenna for wireless communication.
Components 92 and 94 are two of the three different sensors, (the shock signature, flash signature or acoustic signature) that are decoded to determine a valid event
Diode 53 is a laser diode which is a semiconductor device that produces coherent radiation (in which the waves are all at the same frequency and phase) in the visible or infrared spectrum when current passes through it. The most common type of laser diode is formed from a p-n junction and powered by injected electric current. Due to diffraction, the beam diverges (expands) rapidly after leaving the chip, typically at 30 degrees vertically by 10 degrees laterally. A lens must be used in order to form a collimated beam like that produced by a laser pointer. If a circular beam is required, cylindrical lenses and other optics are used. For single spatial mode lasers, using symmetrical lenses, the collimated beam ends up being elliptical in shape, due to the difference in the vertical and lateral divergences Connector 87 provides for hooking up a cable to charge the battery and manually operate the SAT. The Switch 98 turns the SAT off and on and is used to set the different modes of operation.
Screws that thread into the housing hold the cover 33 in place. Battery power supply 80 can pass through a threaded opening 25 in the rear wall 20 of the housing and be held in place by a screwable battery cap 85 . The housing can be mounted to the rifle barrel 190 by an upper clamp 110 under the housing base 10 , and a pivotable clamp 120 having a hinge attached end 123 , and a free-moving end that is held in place by a screw and washer 125 that fastens to the housing base 10 .
FIG. 13 is a perspective view of a dual laser or laser and detector payload system 200 . The payload 50 of the previous figures can be substituted for another payload being a dual laser or laser and detector payload 220 . The other components of the previous figures can be incorporated herein, such as the components 10 , 20 , 30 , 40 , 60 , 70 .
FIG. 14 is a perspective view of a mirror payload embodiment system 250 . The payload 50 of the previous figures can be substituted for another payload being single mirror payload 270 . The other components of the previous figures can be incorporated herein, such as the components 10 , 20 , 30 , 40 , 60 , 70 .
S Shaped Cantilevered Beam
FIG. 15 is an upper front left perspective view of another single laser system 300 with an S shaped cantilevered beam 340 supporting the laser payload 50 . FIG. 16 is an upper front right perspective view of the another single laser system 300 with an S shaped cantilevered beam 340 supporting the laser payload 50 of FIG. 15 . FIG. 17 is a top view of the laser system with S shaped cantilevered beam 340 of FIG. 15 . FIG. 18 is a front view of the laser system with S shaped cantilevered beam 340 of FIG. 15 . FIG. 19 is a right side view of the system with S shaped cantilevered beam 340 of FIG. 15 . FIG. 20 is a left side view of the laser system with S shaped cantilevered beam 340 of FIG. 15 . FIG. 21 is a rear view of the laser system with S shaped cantilevered beam 340 of FIG. 15 . FIG. 22 is an exploded view of the system with S shaped cantilevered beam 340 of FIG. 15 .
Referring to FIGS. 15-22 , the S shaped cantilevered beam 340 can be solid or hollow, with on end 348 mounted to the rear wall 20 of the housing and a cantilevered front end 342 supporting a payload 50 , such as those previously described, wherein the lateral and vertical alignment can be adjustably controlled by rotatable knobs/screws 60 , 70 , as previously described.
Center Deflecting Cantilevered Beam
FIG. 23 is an upper front right perspective view of another single laser system 400 with a center deflecting beam 440 supporting the laser 450 . FIG. 24 is an upper front left perspective view of the center deflecting beam 440 supporting the laser 450 of FIG. 23 . FIG. 25 is a top view of the center deflecting beam 440 supporting the laser 450 of FIG. 23 . FIG. 26 is a front view of the center deflecting beam 440 supporting the laser 450 of FIG. 23 . FIG. 27 is a left side view of the center deflecting beam 440 supporting the laser 450 of FIG. 23 . FIG. 28 is a right side view of the center deflecting beam 440 supporting the laser 450 of FIG. 23 . FIG. 29 is a rear view of the center deflecting beam 440 supporting the laser 450 of FIG. 23 . FIG. 30 is a cross-sectional view of the center deflecting beam 440 supporting the laser along arrow 30 X of FIG. 25 with the beam 440 in a non-deflected state and boresight pointed down
Referring to FIGS. 23-30 , the single laser system 400 with center deflecting beam 400 can include similar components to the previous embodiments. Here, the center deflecting beam 440 can have free ends that are not directly mounted to the rear wall 420 or to the front wall 430 . The beam 440 can have a middle portion 445 , and a rear conical portion 442 with the wide part of the conical portion adjacent to the middle portion 445 . The opposite side of the middle beam portion 445 can have a front conical portion 448 with the wide part of the conical portion adjacent to the middle portion 445 .
A rear mount support 460 attached to the narrow rear end of the conical portion 442 is freely supported within an opening 425 opening in rear wall 420 with the opening 425 having curved interior surface portion(s). The geometry of 460 prevents 440 from rotating about its axis. The front payload support 450 can be attached to the narrow end of the front conical portion 448 can be freely supported within and opening 435 in the front wall 430 of the housing, wherein the opening 435 can also have curved interior surface portion(s). The focus point of the payload can be located at the center of the spherical 450 geometry and there is not linear translation during alignment, only angular movement. A C shaped portion 470 of the housing can be located adjacent to the middle portion 445 of the beam 440 , wherein the lateral adjustment control 460 and vertical adjustment control 470 can each cause the beam 440 to deflect laterally and vertically when needed. The laser support module housing 450 can have at least a lower spherical surface that can slide within the curved interior surface of the opening 435 of the front wall.
FIG. 31 is another cross-sectional view of the center deflecting beam 440 supporting the laser module housing 450 of FIG. 30 with the beam 440 deflected down by the vertical adjustment control 70 with the boresight pointed straight ahead. FIG. 32 is another cross-sectional view of the center deflecting beam 440 supporting the laser module housing 450 of FIG. 30 with the beam 440 deflected down and boresight pointed partially down. FIG. 33 is another cross-sectional view of the center deflecting beam 440 supporting the laser module housing 450 of FIG. 30 with the beam 440 deflected fully down and boresight pointed up.
Housing Bias Angle and Preload
The bias angle can be driven by two design requirements. The first is the vertical and lateral adjustment range from the mechanical boresight when the payload's centerline(s) are parallel to the base centerline. The second is the lateral and vertical preload forces produced by the conical element acting on the housing over the full adjustment range are greater than the lateral and vertical forces produced by the acceleration level in each axis multiplied times the mass of the housing and the effective mass of the conical element.
The plus and minus adjustment range in each axis from mechanical boresight needs to take into accord any manufacturing tolerances in the SAT assembly, the angular mechanical offsets in the weapon and the angular error associated with the shooter's sight picture.
The maximum bias angle in each axis is greater than the deflection angle required by the conical element at minimum deflection of the housing from the free state that produces a force greater than the unloading force plus two times the plus/minus adjustment range from the mechanical boresight.
FIG. 34 shows an example of the relationship between the preload forces over adjustment angle vs. the peak forces due to the acceleration, actual values will vary from system to system.
FIG. 35 shows the milliradian (mrad) pointing error in one axis for a system that unloads during a shock event. The housing holding the laser moves away from the hard adjustment elements toward the spring and then unloads and starts bouncing and the error increases to unacceptable levels during the time period of interest, i.e when the laser needs to be fired.
FIG. 36 shows the mrad pointing error in one axis for the same system that does not unload during the same shock event, the preload has been increased above the G force level. The housing does not move away from the hard adjustment element and the pointing error is defined by the slope of the conical element at the attachment point to the housing. The slope is governed by the conical element bending between the fixed end at the base and the simply supported end at the housing due to the acceleration load.
The angular pointing error vs. time shown in FIG. 36 is when the adjustment element is located 45% of the housing length from the front of the housing. The pointing error can be reduced or minimized by moving the adjustment element location to 80% from the front of the housing, see FIG. 37 . When the Center of Gravity (CG) of the housing is in front of the adjustment point, the force from the housing mass multiplied times the acceleration level produces a bending moment and deflection in the cantilever element opposite the bending moment and deflection in the cantilever element produced by the same acceleration level acting only on the cantilever element.
FIG. 38 is a perspective view of a cam version 500 of the invention. FIG. 39 is another perspective view 500 of the cam version of FIG. 38 . The operator rotates the external knobs which rotate the cams 510 , 520 pushes against the payload, which moves the payload along the vertical and horizontal axis.
While the payload 50 has been described as a laser module, other types of payloads can be used, such as but not limited to a passive receiving elements such as television or electromagnetic spectrum detectors, reflective elements such as optical or electromagnetic spectrum reflectors, active elements such as electromagnetic spectrum transmitters, optical elements that can include refractive or diffractive or reflective optical elements, and indicator or probe components for measuring.
Although rotating knobs and screws can be used other types of vertical and lateral adjustment controls, can be used such other types of threaded elements, cams or levers, or wedges The adjustments could be manual or servo or remotely controlled. The activation could be by electrical, magnetic, thermal, hydraulic or pneumatic actuators. The linear adjustment for each axis(s) can increase or decrease the angular displace relative to the linear adjustment elements. The linear adjustment elements could be actuators, such as solenoids. The threaded elements can employ different thread pitches or differential threaded components to increase or decrease the angular displacement relative to the linear displacement. Bimetallic materials can be used in the adjustment mechanisms. The contact surface between the adjustment element and the housing is curved to minimize the friction and to minimize the pointing errors as the housing moves and rotates relative to the adjustment element.
Different kinematic interfaces can be used at the mating points to reduce errors as required by the system requirements. Typical types of kinematic interfaces include but not limited to; Kelvin clamp, trihedral cup, gothic arch, v-blocks, conical cup, split kinematics to minimize Abbe offset issues, canoe sphere and v-block, flat prismatic components, rose bud couplings and knife edge.
While the invention has been described, disclosed, illustrated and shown in various terms of certain embodiments or modifications which it has presumed in practice, the scope of the invention is not intended to be, nor should it be deemed to be, limited thereby and such other modifications or embodiments as may be suggested by the teachings herein are particularly reserved especially as they fall within the breadth and scope of the claims here appended. | Devices, apparatus, systems and methods for providing accurate linear and angular positioning with a payload mounted to a beam having freely moveable ends. The payload can be a laser pointer mounted on a firearm, which maintains the initial precise pointing during and after exposure in high G shock and vibration environments. Vertical and lateral adjustment controls can adjust minute changes in beam orientation. Precision adjustments can be performed in a zero G, one G, or high G environment and maintains the adjustment during and after being exposed to a high G shock or vibration environment. | 5 |
RELATED APPLICATION
This application is based on application No. 2000-28275 filed in Japan, the entire content of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a technology of setting a plurality of items associated with operation conditions of an image processing apparatus such as a printer or a copier.
2. Description of the Related Art
Some of the recent copiers and printers have not only printing functions but also postprocessing functions performed after printing. The postprocessing functions include stapling, punching and paper folding. Printing is performed based on operation conditions such as “the number of copies”, “the paper size”, “the orientation of printing”, “whether to perform duplex printing or not” and “selection of a paper feed tray.” Postprocessing is performed based on operation conditions such as “whether to perform stapling or not”, “the position stapled”, “whether to perform punching or not”, “the position punched”, “N-up” and “covered binding.”
The user sets operation conditions of a printer or a copier through a printer driver. The printer driver displays on the display an entry screen for entering data for a plurality of items specifying operation conditions. The printer driver registers the data entered by the user as the set values of the corresponding items, and sets the operation conditions.
In recent years, the number of operation conditions has been increasing because the number of printing functions and postprocessing functions has been increasing. Since this increases the number of items for which data is to be entered, it is difficult to display all the items within one entry screen.
For this reason, recent printer drivers accept data entry by displaying a plurality of entry screens so as to be switchable on the display. The items are all classified into a plurality of groups, and an entry screen is provided for each group. The entry screens each have the form of a card and are displayed so as to overlap one another on the display. A desired entry screen is displayed on the top by selecting the tab provided for the entry screen. The tab is labeled with “Setup”, “Finishing” or the like. From the label, the user can grasp the items that can be set on the entry screen up to a point.
Some of the printing functions and the postprocessing functions cannot be selected unless an appropriate value is set for a certain item. For example, in a copier where it is mechanically impossible to perform stapling or punching on the short edge when the paper size is A4, it is necessary that a value making the paper size, for example, A3 be set for the item specifying the paper size.
Moreover, when an operation condition is specified by items existing over a plurality of entry screens, in other words, when it is necessary to enter appropriate data while switching entry screens, the following problem arises: When data is entered for an item on the displayed entry screen, it is necessary for the user to be conscious of the data having been entered or to be entered on other entry screens being hidden. Consequently, data entry requires time and effort, so that operation condition setting cannot be performed quickly and easily.
SUMMARY OF THE INVENTION
An object of the present invention is to provide solutions to the above-mentioned problems.
Another object of the present invention is to provide an image processing apparatus where operation conditions can be easily entered.
Yet another object of the present invention is to provide an image processing apparatus where an appropriate value can be easily set even when an operation condition is specified by items existing over a plurality of entry screens.
Still another object of the present invention is to provide an image processing apparatus where a plurality of operation conditions existing on different entry screens can be easily referred to.
These and other objects are attained by an image processing apparatus having, a plurality of entry screens, first display means for selectively displaying a plurality of entry screens, setting means for setting an operation condition on a displayed entry screen, a list screen on which all the set operation conditions are collectively displayed, and second display means for displaying the entry screen displayed by the first display means and the list screen at the same time.
Moreover, the above-mentioned objects of the present invention are achieved by a setting method having, a first step in which one of a plurality of entry screens is displayed, a second step in which an operation condition is set on the displayed entry screen, a third step in which a plurality of operation conditions is set by repeating the first step and the second step, and a fourth step in which a list of all the set operation conditions and the entry screen are displayed at the same time.
The invention itself, together with further objects and attendant advantages, will best be understood by reference to the following detailed description taken in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view showing the structure of a print system;
FIG. 2 is a view showing a connection among a client computer, a printer server computer and a digital copier;
FIG. 3 is a view showing a print dialog box of a word processing application;
FIG. 4 is a view showing a properties window of a printer driver;
FIG. 5 is a view showing an entry screen of “Setup”;
FIG. 6 is a view showing an entry screen of “Advanced”;
FIG. 7 is a view showing an entry screen of “Finishing”;
FIG. 8 is a flowchart showing processing performed by a client computer;
FIG. 9 is a flowchart showing operation condition setting processing shown in FIG. 8 ;
FIG. 10 is a view showing part of a determination table;
FIG. 11 is a view showing a list of setting results; and
FIGS. 12 to 17 are views showing other examples of the list of setting results.
In the following description, like parts are designated by like reference numbers throughout the several drawings.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1 , the print system has a plurality of client computers 10 , 12 , 14 and 16 , a printer server computer 20 and a digital copier 30 . The client computers 10 , 12 , 14 and 16 and the printer server computer 20 are connected to a network 40 .
Data and various commands can be communicated among the client computers 10 , 12 , 14 and 16 and between each of the client computers 10 , 12 , 14 and 16 and the printer server computer 20 .
As shown in FIG. 2 , the client computers 10 , 12 , 14 and 16 are provided with a word processing application 10 A and a printer driver 10 B. The digital copier 30 is connected to the printer server computer 20 , and is capable of not only copying but also printing of data received from the client computers 10 , 12 , 14 and 16 by way of the printer server computer 20 .
As shown in FIG. 3 , the word processing application 10 A displays a screen for print setting (print dialog box 50 ) on a display connected to the computer. As shown in FIG. 4 , the printer driver 10 B displays a screen for setting edit functions of the digital copier 30 (properties window 60 ) on the display. The edit function is a generic name for the print functions and the postprocessing functions performed after printing.
When the user clicks on a properties button 51 in the print dialog box 50 , the properties window 60 opens. When the user clicks on an OK button 61 in the properties window 60 , the properties window 60 closes after the set values are updated. When the user clicks on a cancel button 62 , the properties window 60 closes without the set values updated. When an apply button 63 is clicked on, although the set values are updated, the properties window 60 remains open.
On the print dialog box 50 , of the operation conditions associated with the print functions, basic ones such as “printer selection”, “the print area” and “the number of copies” can be set. When the user clicks on an OK button 52 in the print dialog box 50 , printing and postprocessing are started.
On the properties window 60 , values can be set for a plurality of items specifying operation conditions associated with printing and a plurality of items specifying operation conditions associated with postprocessing. Since the number of items is large, a plurality of (in the illustrated example, eleven) entry screens 64 , 66 , 67 , 68 are displayed so as to be switchable in the properties window 60 . The items are all classified into a plurality of groups, and an entry screen is provided for each group. The entry screens 64 , 66 , 67 , 68 each have the form of a card and are displayed so as to overlap one another. A tab 65 is provided at the upper end of each entry screen. The eleven tabs 65 a–g do not overlap one another. The tabs 65 a–g are labeled with “General”, “Details”, “Setup”, “Advanced”, “Finishing ”, “Graphics”, “Font” and the like. When the user clicks on a tab 65 , the entry screen 64 provided with the tab 65 is displayed on the top.
FIG. 5 shows an example of an entry screen 66 of a group “Setup.” FIG. 6 shows an example of an entry screen 67 of a group “Advanced.” FIG. 7 shows an example of an entry screen 68 of a group “Finishing.” In the following description, the entry screens 66 to 68 will also be referred to as “Setup tab 66 ”, “Advanced tab 67 ”, and “Finishing tab 68 ”, respectively.
The items displayed on the entry screens 66 to 68 are as follows:
(1) Setup tab 66 ( FIG. 5 )
“Copies”: item specifying the number of copies
“Paper Size”: item specifying the paper size
“Orientation”: item specifying the orientation of printing with respect to the sheet
“Paper Source”: item specifying the paper feed tray
(2) Advanced tab 67 ( FIG. 6 )
“Duplex Print”: item specifying whether to perform duplex printing or not, and the position of the binding margin in duplex printing
“Layout”: item specifying a layout such as N-up or magazine binding
“Watermarks”: item specifying printing of watermarks
(3) Finishing tab 68 ( FIG. 7 )
“Collate”: item specifying the order of output when a plurality of copies is printed
“Staple”: item specifying the position where the printed sheets are stapled
“Hole-Punch”: item specifying the position where the printed sheets are punched
“Folding”: item specifying folding of the printed sheets
While the other entry screens are not shown, on the entry screen of a group “Graphics”, items specifying whether to perform halftone processing or not, contrast adjustment and the like are shown. On the entry screen of a group “Font”, items specifying whether to print the data as it is in a True Type font or not and the like are shown.
FIG. 8 is a flowchart showing the processing performed by the client computer 10 .
The user creates a document by use of the word processing application 10 A that runs on the client computer 10 (S 11 ). When an instruction to print the document is provided (“Y” of S 12 ), the word processing application 10 A displays the print dialog box 50 on the display (S 13 ).
On the print dialog box 50 , the user selects the digital copier 30 or the printer to which the data is output (S 14 ). When the user clicks on the properties button 51 (“Y” of S 15 ), the printer driver 10 B of the selected digital copier 30 is activated. The printer driver 10 B sets values for a plurality of items specifying operation conditions associated with editing (S 16 ).
In a case where the properties button 51 is not clicked on (“N” of S 15 ) or after the operation condition setting by the printer driver 10 B is finished, when the OK button 52 in the print dialog box 50 is clicked on (“Y” of S 17 ), the digital copier 30 starts printing and postprocessing (S 18 ). The digital copier 30 operates based on the operation conditions set by the printer driver 10 B at step S 16 .
FIG. 9 is a flowchart showing the operation condition setting processing (S 16 ) shown in FIG. 8 .
The printer driver 10 B displays the properties window 60 on the display (“Y” of S 21 ). The printer driver 10 B calls up pre-registered default values, and sets the default values for the corresponding items (S 22 ).
The user clicks on a tab 65 labeled with a desired one of a plurality of groups. The printer driver 10 B selects the group the tab 65 of which is clicked on, and generates an entry screen for entering data for the items belonging to the selected group (S 23 ). The printer driver 10 B displays the generated entry screen in the properties window 60 (S 23 ).
The printer driver 10 B judges the operation condition setting results based on the set values of all the items, and generates a list of setting results (S 24 ). The printer driver 10 B displays a list 81 as shown in FIG. 11 on the display (S 24 ). The setting result list 81 will be described later.
When the user enters data for an item on the displayed entry screen, the printer driver 10 B determines that a set value has been changed (“Y” of S 25 ). However, setting at which the digital copier 30 cannot operate must be avoided. More specifically, setting of items associated with edit functions not supported by the digital copier 30 must be inhibited. Setting contradictory to an already set value must also be inhibited.
Therefore, with reference to a determination table 70 as shown in FIG. 10 , the printer driver 10 B detects combinations of set values at which the digital copier 30 can operate (S 26 ). The printer driver 10 B determines whether the entered data can be set as a new set value or not (S 27 ). This determination is made based on whether combination of the entered data and the set value of another item is inhibited or not.
When the setting is impossible (“N” of S 27 ), the printer driver 10 B provides the user with an error notification that the setting is inhibited, and prompts the user to enter appropriate data (S 28 ). Moreover, the printer driver 10 B is capable of forcibly setting a value at which the digital copier 30 can operate and notifying the user of this.
When the setting is possible (“Y” of S 27 ), the printer driver 10 B registers the entered data as the set value of the corresponding item (S 29 ).
The printer driver 10 B again judges the operation condition setting results based on the set values of all the items, and displays an updated setting result list 81 (S 30 ).
When the user enters data for another item on the same entry screen (“N” of S 31 , “N” of S 32 ), the printer driver 10 B performs steps S 25 to S 30 and updates the list 81 .
When the user clicks on another tab 65 (“Y” of S 31 ), after displaying the selected entry screen on the top (S 23 ), the printer driver 10 B performs steps S 24 to S 30 and updates the list 81 .
When the user clicks on the OK button 61 in the properties window 60 (“Y” of S 32 ), the printer driver 10 B updates the set values of the items and closes the properties window 60 .
FIG. 10 shows part of the determination table 70 .
In the determination table 70 , combinations of set values at which the digital copier 30 can operate and combinations of set values at which the digital copier 30 cannot operate are recorded. The determination table 70 differs among the apparatuses to which data is output. The determination table 70 is provided in the form of a file as part of the printer driver 10 B.
In the determination table 70 , the “pre-set mode” represents items the set values of which have already been set, and the “post-set model” represents items the set values of which are to be changed. Inhibited combinations of the post-set mode and the preset mode are indicated by “X”, whereas permitted combinations are indicated by “∘.”
The shown determination table 70 is referred to when the items of the group “Setup” are the preset mode and the items of the group “Finishing” is the post-set mode. In the digital copier 30 shown as an example, when the paper size is A4, it is mechanically impossible to perform stapling or punching on the short edge. Therefore, the cell representative of combination of “Short Edge 2-points” of the item “Staple” and “A4” of the item “Paper Size” is marked with “X”. The cell representative of combination of “Short Edge Punch” of the item “Hole-Punch” and “A4” is also marked with “X”. On the contrary, the cell representative of combination of “Long Edge 2-points” of the item “Staple” and “A4” is marked with “∘”. The combinations marked with “∘” indicate that the digital copier 30 can operate without a hitch at these combinations of setting values.
When the user tries to set “Short Edge 2-points” or “Short Edge Punch” although the set paper size is A4, the printer driver 10 B detects that the combination is inhibited with reference to the determination table 70 . Consequently, the printer driver 10 B inhibits such setting. When the user sets “Long Edge 2-points” in a case where the set paper size is A4, the printer driver 10 B detects that the combination is permitted with reference to the determination table 70 . Consequently, the printer driver 10 B registers “Long Edge 2-points” for the item “Staple” as a new set value.
FIG. 11 is a view showing an example of the setting result list 81 .
The list 81 is displayed in a setting confirmation window 80 . The setting confirmation window 80 is opened separately from the properties window 60 on the display. The printer driver 10 B always opens the setting confirmation window 80 when the properties window 60 is opened. However, the present invention is not limited to this configuration. For example, the printer driver 10 B may open the setting confirmation window 80 to display the list 81 only when instructed to do so by the user.
The list 81 has a plurality of label fields 82 and data fields 83 disposed on the right of the label fields 82 . In the label fields 82 , the titles of the setting results are displayed. In the data fields 83 , the set values and options are concretely displayed.
In the list 81 , “Copies”, “Paper Size”, “Paper Source”, “Duplex Print”, “Layout”, “Collate”, “Staple” and “Hole-Punch” are displayed as the titles of the setting results. In FIG. 11 , the set values and conditions are as follows: the number of copies, “1”; the paper size, “A4”; the paper feed tray, “Auto”; the duplex print, “None”; the layout, “None”; the position stapled, “Corner Staple”; and the position punched, “Short Edge Punch.”
In the data field 83 of the title “Collate”, the word “Collate” and an inhibition mark 84 are displayed. The inhibition mark 84 is added to the item the setting of which is inhibited. The setting of “Collate” is inhibited for the following reason: Since the currently set number of copies is one, it is meaningless to set “Uncollated” for the item “Collate” of the finishing tab 68 . By adding the inhibition mark 84 , the user can easily find the item the setting of which is inhibited. The means for notifying the user of inhibition of setting is not limited to the inhibition mark 84 . For example, the title the setting of which is inhibited may be displayed in color, the word and the background in the data field 83 may be displayed in reverse video or the data field 83 may be grayed out.
To inhibit the setting by the user, the printer driver 10 B grays out the items the setting of which is inhibited on the entry screen. In the above-described example, the printer driver 10 B grays out the item “Collate” of the Finishing tab 68 . The printer driver 10 B is capable of displaying the reason for the inhibition as well as inhibiting setting. In the above-described example, a message “The set number of copies is one.” or the like is displayed in a memo field provided in the properties window 60 .
The shown list 81 shows the results of setting made on the Setup tab 66 , the Advanced tab 67 and the Finishing tab 68 ( FIGS. 5 to 7 ). However, the setting results of the item “Orientation” on the Setup tab 66 , the item “Watermarks” on the Advanced tab 67 and the item “Folding” on the Finishing tab 68 are not shown. Further, the results of setting made on the other entry screens are not shown, either. These results are not shown for simplification of the description and not with the intention of limiting the present invention. Therefore, a list of all the setting results including the setting results not shown or described or a list of some of the setting results can be displayed.
Displaying a list of the operation condition setting results produces the following advantage: When data is entered for an item on the displayed entry screen, it is unnecessary for the user to be conscious of or memorize the data having been entered or to be entered on other entry screens being hidden. Therefore, even when an operation condition is specified by items existing over a plurality of entry screens, data entry is not complicated, so that an appropriate value can be quickly and easily set.
The setting result list is not limited to the above-described configuration, but may be modified as shown in FIGS. 12 to 17 .
FIG. 12 is a view showing a relevant part of another example of the setting result list. The list 81 shown in FIG. 11 is generated by use of letters and numbers. On the contrary, a list 85 shown in FIG. 12 is created by use of symbols including letters, numbers and icons.
Description will be given using as an example “N-up” which is a setting result of the item “Layout” on the Advanced tab 67 . The printer driver 10 B generates the list 85 by use of an icon 86 representative of a condition “N-up: None”, and displays the list 85 in the setting confirmation window 80 . When the user set “2-up” for the item “Layout” under this condition, the printer driver 10 B updates the list 85 to one using an icon 87 representative of a condition “2-up.”
By generating the list 85 by use of the icons 86 and 87 , the user can intuitively or visually grasp the setting results.
FIG. 13 is a view showing a relevant part of another example of the setting result list. The printer driver 10 B generates a list 91 including settable values, and displays the list 91 in the setting confirmation window 80 . The settable values include setting ranges and options of the items.
The list 91 has a plurality of label fields 92 and first and second data fields 93 and 94 disposed on the right of the label fields 92 . In the first data fields 93 , the set values and options are concretely displayed. In the second data fields 94 , the settable values are displayed in accordance with the functions supported by the digital copier 30 . For example, with respect to the number of copies, the set number “1” is displayed in the first data field 93 , and the settable range “(1–999)” is displayed in the second data field 94 . Likewise, with respect to the paper size, “A4/Letter” representative of the settable options is displayed in the second data field 94 . With respect to the paper feed tray, “Tray 1/2” representative of the settable options is displayed in the second data field 94 .
By generating the list 91 including the settable values, the user can easily find the settable ranges and options.
FIG. 14 is a view showing another example of the setting result list. In the list 101 , the results of setting associated with the currently displayed entry screen are shown so as to be distinguished from the other setting results.
The list 101 has label fields 102 and data fields 103 . Description will be given using as an example a case where the Advanced tab 67 is displayed on the top. First, the printer driver 10 B identifies, among the setting results shown in the list 101 , “Duplex Print” and “Layout” which are setting results decided based on the displayed Advanced tab 67 . Then, the printer driver 10 B generates the list 101 in which the identified “Duplex Print” and “Layout” are distinguished from the other setting results, and displays the list 101 in the setting confirmation window 80 . The “Duplex Print” and “Layout” are distinguished from the other setting results by displaying the letters and the background in the data fields 103 in reverse video. The identified setting results may be distinguished from the other setting results by displaying the titles of the identified setting results in a different color from the other titles or by adding a mark.
Displaying the setting results associated with the currently displayed entry screen so as to be distinguished in the list 101 produces the following advantage: From the list 101 , the user can easily find whether the entry screen including the item which the user intends to set is displayed or not. In the above-described example, the user finds that the Advanced tab 67 on which “Duplex Print” and “Layout” can be set is displayed.
FIG. 15 is a view showing another example of the setting result list. On the list 105 , the user can specify the entry screen which the user intends to display.
The list 105 has a plurality of label fields 106 and buttons 107 disposed on the right of the label fields 106 . The buttons 107 are provided for selecting a setting result from among the setting results shown in the list 105 . In the data field provided on each button 107 , the set value or option is concretely displayed. For example, with respect to “Paper Size”, the set paper size “A4” is displayed on the button 107 .
Assume that the user clicks on the button 107 on which “A4” is displayed. This button 107 corresponds to, “Paper Size.” Then, the printer driver 10 B switches the entry screen to the Setup tab 66 including the item “Paper Size” deciding the selected setting result “Paper Size”, and displays the Setup tab 66 . The titles may be displayed on buttons.
Since the displayed entry screen can be switched on the list 105 , the following advantage is produced: Even when a plurality of entry screens is displayed so as to overlap one another, the user can immediately display the target entry screen merely by clicking on the button 107 on which the item the user intends to set is displayed. Since the user is saved from having to repetitively click on the tab 65 until the target entry screen is displayed, operation condition setting can be performed more quickly and easily.
FIGS. 16 and 17 show other examples of the setting result list. FIG. 16 shows a condition where the Setup tab 66 is displayed in the properties window 60 . FIG. 17 shows a condition where the Advanced tab 67 is displayed in the properties window 60 .
The list 81 shown in FIG. 10 is displayed in the setting confirmation window 80 opened separately from the properties window 60 . On the contrary, a list 111 shown in FIGS. 16 and 17 is displayed in the properties window 60 . Although the entry screen is switched from the Setup tab 66 of FIG. 16 to the Advanced tab 67 of FIG. 17 by clicking on the tab 65 , the list 111 is always displayed.
Storing a program describing the processing as shown in FIG. 9 in a computer-readable record medium allows a computer to function as an edit function setter or a printer driver.
As described above, according to the operation condition setting technology of this embodiment, since a list of operation condition setting results is displayed, even when an operation condition is specified by items existing over a plurality of entry screens, an appropriate value can be easily set.
Although the present invention has been fully described by way of examples with reference to the accompanying drawings, it is to be noted that various changes and modifications will be apparent to those skilled in the art. Therefore, unless such changes and modifications depart from the scope of the present invention, they should be construed as being included therein. | In an image processing apparatus which has a plurality of overlapping entry screens, a desired one is selectively displayed and various operation conditions are set on the selected entry screen. The contents of all the set operation conditions are displayed in the form of a list. The list is displayed together with an entry screen. | 6 |
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Application Ser. No. 60/861,996 filed Nov. 30, 2006, and U.S. Provisional Application Ser. No. 60/860,645 filed Nov. 22, 2006.
FIELD OF INVENTION
[0002] The present application relates to benefit agent containing delivery particles, compositions comprising such particles, and processes for making and using such particles and compositions.
BACKGROUND OF THE INVENTION
[0003] Benefit agents, such as perfumes, silicones, waxes, flavors, vitamins and fabric softening agents, are expensive and generally less effective when employed at high levels in personal care compositions, cleaning compositions, and fabric care compositions. As a result, there is a desire to maximize the effectiveness of such benefit agents. One method of achieving such objective is to improve the delivery efficiencies of such benefit agents. Unfortunately, it is difficult to improve the delivery efficiencies of benefit agents as such agents may be lost do to the agents' physical or chemical characteristics, or such agents may be incompatible with other compositional components or the situs that is treated.
[0004] Accordingly, there is a need for a benefit agent containing delivery particle that provides improved benefit agent delivery efficiency.
SUMMARY OF THE INVENTION
[0005] The present invention relates to benefit agent containing delivery particles comprising a core material and a wall material that at least partially surrounds the core material. The present invention also relates to compositions comprising said particles, and processes for making and using such particles and compositions.
DETAILED DESCRIPTION OF THE INVENTION
Definitions
[0006] As used herein “consumer product” means baby care, beauty care, fabric & home care, family care, feminine care, health care, snack and/or beverage products or devices intended to be used or consumed in the form in which it is sold, and not intended for subsequent commercial manufacture or modification. Such products include but are not limited to diapers, bibs, wipes; products for and/or methods relating to treating hair (human, dog, and/or cat), including, bleaching, coloring, dyeing, conditioning, shampooing, styling; deodorants and antiperspirants; personal cleansing; cosmetics; skin care including application of creams, lotions, and other topically applied products for consumer use; and shaving products, products for and/or methods relating to treating fabrics, hard surfaces and any other surfaces in the area of fabric and home care, including: air care, car care, dishwashing, fabric conditioning (including softening), laundry detergency, laundry and rinse additive and/or care, hard surface cleaning and/or treatment, and other cleaning for consumer or institutional use; products and/or methods relating to bath tissue, facial tissue, paper handkerchiefs, and/or paper towels; tampons, feminine napkins; products and/or methods relating to oral care including toothpastes, tooth gels, tooth rinses, denture adhesives, tooth whitening; over-the-counter health care including cough and cold remedies, pain relievers, RX pharmaceuticals, pet health and nutrition, and water purification; processed food products intended primarily for consumption between customary meals or as a meal accompaniment (non-limiting examples include potato chips, tortilla chips, popcorn, pretzels, corn chips, cereal bars, vegetable chips or crisps, snack mixes, party mixes, multigrain chips, snack crackers, cheese snacks, pork rinds, corn snacks, pellet snacks, extruded snacks and bagel chips); and coffee.
[0007] As used herein, the term “cleaning composition” includes, unless otherwise indicated, granular or powder-form all-purpose or “heavy-duty” washing agents, especially cleaning detergents; liquid, gel or paste-form all-purpose washing agents, especially the so-called heavy-duty liquid types; liquid fine-fabric detergents; hand dishwashing agents or light duty dishwashing agents, especially those of the high-foaming type; machine dishwashing agents, including the various tablet, granular, liquid and rinse-aid types for household and institutional use; liquid cleaning and disinfecting agents, including antibacterial hand-wash types, cleaning bars, mouthwashes, denture cleaners, dentifrice, car or carpet shampoos, bathroom cleaners; hair shampoos and hair-rinses; shower gels and foam baths and metal cleaners; as well as cleaning auxiliaries such as bleach additives and “stain-stick” or pre-treat types, substrate-laden products such as dryer added sheets, dry and wetted wipes and pads, nonwoven substrates, and sponges; as well as sprays and mists.
[0008] As used herein, the term “fabric care composition” includes, unless otherwise indicated, fabric softening compositions, fabric enhancing compositions, fabric freshening compositions and combinations there of.
[0009] As used herein, the phrase “benefit agent containing delivery particle” encompasses microcapsules including perfume microcapsules.
[0010] As used herein, the terms “particle”, “benefit agent containing delivery particle”, “capsule” and “microcapsule” are synonymous.
[0011] As used herein, the articles including “a” and “an” when used in a claim, are understood to mean one or more of what is claimed or described.
[0012] As used herein, the terms “include”, “includes” and “including” are meant to be non-limiting.
[0013] The test methods disclosed in the Test Methods Section of the present application should be used to determine the respective values of the parameters of Applicants' inventions.
[0014] Unless otherwise noted, all component or composition levels are in reference to the active portion of that component or composition, and are exclusive of impurities, for example, residual solvents or by-products, which may be present in commercially available sources of such components or compositions.
[0015] All percentages and ratios are calculated by weight unless otherwise indicated. All percentages and ratios are calculated based on the total composition unless otherwise indicated.
[0016] It should be understood that every maximum numerical limitation given throughout this specification includes every lower numerical limitation, as if such lower numerical limitations were expressly written herein. Every minimum numerical limitation given throughout this specification will include every higher numerical limitation, as if such higher numerical limitations were expressly written herein. Every numerical range given throughout this specification will include every narrower numerical range that falls within such broader numerical range, as if such narrower numerical ranges were all expressly written herein.
Benefit Agent Containing Delivery Particle
[0017] Applicants discovered that the problem of achieving effective and efficient benefit agent delivery can be solved in an economical manner when a benefit agent containing delivery particle, having comprising a core material and a wall material that at least partially surrounds said core material and a certain combination of physical and chemical characteristics is employed. Such physical and chemical characteristics are defined by the Volume Weighted Fracture Strength. The delivery effectiveness and efficiency can be further tailored by selecting particles having the following Volume Weighted Fracture Strengths as listed for each application:
1.) Type 1 Benefit Agent Containing Delivery Particles (Type 1 Particles). Such particles may be employed when a benefit, for example, odor is desired in/from a wash solution. Such particles may have a Volume Weighted Fracture Strength less than about 0.8 MPa, from about 0.8 MPa to about 0.1 MPa, or even from about 0.75 MPa to about 0.25 MPa. 2.) Type 2 Benefit Agent Containing Delivery Particles (Type 2 Particles). Such particles may be employed when a benefit, for example, odor is desired from a wet situs. Such particles may have a Volume Weighted Fracture Strength from about 0.5 MPa to about 2 MPa, from about 0.8 MPa to about 1.8 MPa, or even from about 1 MPa to about 1.7 MPa. 3.) Type 3 Benefit Agent Containing Delivery Particles (Type 3 Particles). Such particles may be employed when a benefit, for example, odor is desired from a dry situs dried after being contacted with such particles. Such particles may have a Volume Weighted Fracture Strength from about 1.5 MPa or even 2 MPa to about 5 MPa, from about 1.5 MPa or even 2 MPa to about 4 MPa, or from about 1.5 MPa or even 2 MPa to about 3 MPa. 4.) Type 4 Benefit Agent Containing Delivery Particles (Type 4 Particles). Such particles may be employed when a benefit, for example, odor is desired from a situs during wear/use after such situs is contacted with such particles. Such particle may have a Volume Weighted Fracture Strength from about 5 MPa to about 16 MPa, from about 5 MPa to about 9 MPa, or even from about 6 MPa to about 8 MPa.
[0022] In short, the level of benefit at any one point may be tailored by selecting the desired amount type of each class of benefit agent containing delivery particle.
[0023] In one aspect, Applicants disclose a particle composition wherein the total volume weight of the particles is 100% and the volume weight of each type of particle may be as follows:
Type 1 Particles. From about 0% to about 100%, from about 5% to about 50%, or even from about 5% to about 25%; Type 2 Particles: From about 0% to about 100%, from about 5% to about 50%, or even from about 5% to about 25%; Type 3 Particles: From about 0% to 100%, from about 5% to about 90%, or even from about 5% to about 25%; and Type 4 Particles: From about 0% to about 100%, from about 5% to about 50%, or even from about 5% to about 25%.
With the proviso that the sum of the percentage of the Type 1, 2, 3 and 4 Benefit Agent Containing Delivery Particles is always 100%—such sum cannot exceed or be less than 100%.
[0028] In one aspect, a consumer product comprising from about 0.001% to about 25%, from about 0.001% to about 10%, or from about 0.01% to about 3%, based on total consumer product mass weight, of the aforementioned particle composition is disclosed.
[0029] In one aspect, a cleaning composition comprising from about 0.005% to about 10%, from about 0.01% to about 3%, or from about 0.1% to about 1% based on total cleaning composition mass weight of the aforementioned particle composition is disclosed.
[0030] In one aspect, a fabric care composition comprising from about 0.005% to about 10%, from about 0.01% to about 3%, or from about 0.1% to about 1% based on total fabric care mass weight of the aforementioned particle composition is disclosed.
[0031] In one aspect, when the aforementioned particle composition is employed in a consumer product, for example a liquid consumer product, the particle composition may have a deposition of at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or even 100%.
[0032] In one aspect, when the aforementioned particle composition is employed in a consumer product, for example a liquid consumer product, the particle composition may have less than 50%, 40%, 30%, 20%, 10% or even 0% leakage of the encapsulated benefit agent from the microcapsules of said particle composition into said consumer product.
[0033] Useful wall materials include materials selected from the group consisting of polyethylenes, polyamides, polystyrenes, polyisoprenes, polycarbonates, polyesters, polyacrylates, polyureas, polyurethanes, polyolefins, polysaccharides, epoxy resins, vinyl polymers, and mixtures thereof. In one aspect, useful wall materials include materials that are sufficiently impervious to the core material and the materials in the environment in which the benefit agent containing delivery particle will be employed, to permit the delivery benefit to be obtained. Suitable impervious wall materials include materials selected from the group consisting of reaction products of one or more amines with one or more aldehydes, such as urea cross-linked with formaldehyde or gluteraldehyde, melamine cross-linked with formaldehyde; gelatin-polyphosphate coacervates optionally cross-linked with gluteraldehyde; gelatin-gum Arabic coacervates; cross-linked silicone fluids; polyamine reacted with polyisocyanates and mixtures thereof. In one aspect, the wall material comprises melamine cross-linked with formaldehyde.
[0034] Useful core materials include perfume raw materials, silicone oils, waxes, hydrocarbons, higher fatty acids, essential oils, lipids, skin coolants, vitamins, sunscreens, antioxidants, glycerine, catalysts, bleach particles, silicon dioxide particles, malodor reducing agents, odor-controlling materials, chelating agents, antistatic agents, softening agents, insect and moth repelling agents, colorants, antioxidants, chelants, bodying agents, drape and form control agents, smoothness agents, wrinkle control agents, sanitization agents, disinfecting agents, germ control agents, mold control agents, mildew control agents, antiviral agents, drying agents, stain resistance agents, soil release agents, fabric refreshing agents and freshness extending agents, chlorine bleach odor control agents, dye fixatives, dye transfer inhibitors, color maintenance agents, optical brighteners, color restoration/rejuvenation agents, anti-fading agents, whiteness enhancers, anti-abrasion agents, wear resistance agents, fabric integrity agents, anti-wear agents, anti-pilling agents, defoamers and anti-foaming agents, UV protection agents for fabrics and skin, sun fade inhibitors, anti-allergenic agents, enzymes, water proofing agents, fabric comfort agents, shrinkage resistance agents, stretch resistance agents, stretch recovery agents, skin care agents, glycerin, and natural actives such as aloe vera, vitamin E, shea butter, cocoa butter, and the like, brighteners, antibacterial actives, antiperspirant actives, cationic polymers, dyes and mixtures thereof. In one aspect, said perfume raw material is selected from the group consisting of alcohols, ketones, aldehydes, esters, ethers, nitrites alkenes. In one aspect the core material comprises a perfume. In one aspect, said perfume comprises perfume raw materials selected from the group consisting of alcohols, ketones, aldehydes, esters, ethers, nitrites alkenes and mixtures thereof. In one aspect, said perfume may comprise a perfume raw material selected from the group consisting of perfume raw materials having a boiling point (B.P.) lower than about 250° C. and a ClogP lower than about 3, perfume raw materials having a B.P. of greater than about 250° C. and a ClogP of greater than about 3, perfume raw materials having a B.P. of greater than about 250° C. and a ClogP lower than about 3, perfume raw materials having a B.P. lower than about 250° C. and a ClogP greater than about 3 and mixtures thereof. Perfume raw materials having a boiling point B.P. lower than about 250° C. and a ClogP lower than about 3 are known as Quadrant I perfume raw materials, perfume raw materials having a B.P. of greater than about 250° C. and a ClogP of greater than about 3 are known as Quadrant IV perfume raw materials, perfume raw materials having a B.P. of greater than about 250° C. and a ClogP lower than about 3 are known as Quadrant II perfume raw materials, perfume raw materials having a B.P. lower than about 250° C. and a ClogP greater than about 3 are known as a Quadrant III perfume raw materials. In one aspect, said perfume comprises a perfume raw material having B.P. of lower than about 250° C. In one aspect, said perfume comprises a perfume raw material selected from the group consisting of Quadrant I, II, III perfume raw materials and mixtures thereof. In one aspect, said perfume comprises a Quadrant III perfume raw material. Suitable Quadrant I, II, III and IV perfume raw materials are disclosed in U.S. Pat. No. 6,869,923 B1.
[0035] In one aspect, said perfume comprises a Quadrant IV perfume raw material. While not being bound by theory, it is believed that such Quadrant IV perfume raw materials can improve perfume odor “balance”. Said perfume may comprise, based on total perfume weight, less than about 30%, less than about 20%, or even less than about 15% of said Quadrant IV perfume raw material.
[0036] In one aspect, said benefit agent delivery particles' core material comprises:
a.) a perfume composition having a Clog P of less than 4.5; b.) a perfume composition comprising, based on total perfume composition weight, 60% perfume materials having a Clog P of less than 4.0; c.) a perfume composition comprising, based on total perfume composition weight, 35% perfume materials having a Clog P of less than 3.5; d.) a perfume composition comprising, based on total perfume composition weight, 40% perfume materials having a Clog P of less than 4.0 and at least 1% perfume materials having a Clog P of less than 2.0; e.) a perfume composition comprising, based on total perfume composition weight, 40% perfume materials having a Clog P of less than 4.0 and at least 15% perfume materials having a Clog P of less than 3.0; f.) a perfume composition comprising, based on total perfume composition weight, at least 1% butanoate esters and at least 1% of pentanoate esters; g.) a perfume composition comprising, based on total perfume composition weight, at least 2% of an ester comprising an allyl moiety and at least 10% of another perfume comprising an ester moiety; h.) a perfume composition comprising, based on total perfume composition weight, at least 1% of an aldehyde comprising an alkyl chain moiety; i.) a perfume composition comprising, based on total perfume composition weight, at least 2% of a butanoate ester; j.) a perfume composition comprising, based on total perfume composition weight, at least 1% of a pentanoate ester; k.) a perfume composition comprising, based on total perfume composition weight, at least 3% of an ester comprising an allyl moiety and 1% of an aldehyde comprising an alkyl chain moiety; l.) a perfume composition comprising, based on total perfume composition weight, at least 25% of a perfume comprising an ester moiety and 1% of an aldehyde comprising an alkyl chain moiety; m.) a perfume compositions comprising, based on total perfume composition weight, at least 2% of a material selected from 4-(2,6,6-trimethyl-1-cyclohexenyl)-3-buten-2-one, 4-(2,6,6-trimethyl-2-cyclohexenyl)-3-buten-2-one and 3-buten-2-one, 3-methyl-4-(2,6,6-trimethyl-1-cyclohexen-2-yl)- and mixtures thereof; n.) a perfume composition comprising, based on total perfume composition weight, at least 0.1% of tridec-2-enonitrile, and mandaril, and mixtures thereof; o.) a perfume composition comprising, based on total perfume composition weight, at least 2% of a material selected from 3,7-dimethyl-6-octene nitrile, 2-cyclohexylidene-2-phenylacetonitrile and mixtures thereof; p.) a perfume composition comprising, based on total perfume composition weight, at least 80% of one or more perfumes comprising a moiety selected from the group consisting of esters, aldehydes, ionones, nitrites, ketones and combinations thereof; q.) a perfume composition comprising, based on total perfume composition weight, at least 3% of an ester comprising an allyl moiety; a perfume composition comprising, based on total perfume composition weight, at least 20% of a material selected from the group consisting of: 1-methylethyl-2-methylbutanoate; ethyl-2-methyl pentanoate; 1,5-dimethyl-1-ethenylhexyl-4-enyl acetate; p-metnh-1-en-8-yl acetate; 4-(2,6,6-trimethyl-2-cyclohexenyl)-3-buten-2-one; 4-acetoxy-3-methoxy-1-propenylbenzene; 2-propenyl cyclohexanepropionate; bicyclo[2.2.1]hept-5-ene-2-carboxylic acid, 3-(1-methylethyl)-ethyl ester; bycyclo[2.2.1]heptan-2-ol, 1,7,7-trimethyl-, acetate 1,5-dimethyl-1-ethenylhex-4-enylacetate; hexyl 2-methyl propanoate; ethyl-2-methylbutanoate; 4-undecanone; 5-heptyldihydro-2(3h)-furanone; 1,6-nonadien-3-ol, 3,7dimethyl-; 3,7-dimethylocta-1,6-dien-3-o; 3-cyclohexene-1-carboxaldehyde, dimethyl-; 3,7-dimethyl-6-octene nitrile; 4-(2,6,6-trimethyl-1-cyclohexenyl)-3-buten-2-one; tridec-2-enonitrile; patchouli oil; ethyl tricycle[5.2.1.0]decan-2-carboxylate; 2,2-dimethyl-cyclohexanepropanol; hexyl ethanoate, 7-acetyl, 1,2,3,4,5,6,7,8-octahydro-1,1,6,7-tetramethyl naphtalene; allyl-cyclohexyloxy acetate; methyl nonyl acetic aldehyde; 1-spiro[4,5]dec-7-en-7-yl-4-pentenen-1-one; 7-octen-2-ol, 2-methyl-6-methylene-, dihydro; cyclohexanol, 2-(1,1-dimethylethyl)-, acetate; hexahydro-4,7-methanoinden-5(6)-yl propionatehexahydro-4,7-methanoinden-5(6)-yl propionate; 2-methoxynaphtalene; 1-(2,6,6-trimethyl-3-cyclohexenyl)-2-buten-1-one; 1-(2,6,6-trimethyl-2-cyclohexenyl)-2-buten-1-one; 3,7-dimethyloctan-3-ol; 3-buten-2-one, 3-methyl-4-(2,6,6-trimethyl-1-cyclohexen-2-yl)-; hexanoic acid, 2-propenyl ester; (z)-non-6-en-1-al; 1-decyl aldehyde; 1-octanal; 4-t-butyl-α-methylhydrocinnamaldehyde; alpha-hexylcinnamaldehyde; ethyl-2,4-hexadienoate; 2-propenyl 3-cyclohexanepropanoate; and mixtures thereof; r.) a perfume composition comprising, based on total perfume composition weight, at least 20% of a material selected from the group consisting of: 1-methylethyl-2-methylbutanoate; ethyl-2-methyl pentanoate; 1,5-dimethyl-1-ethenylhex-4-enyl acetate; p-menth-1-en-8-yl acetate; 4-(2,6,6-trimethyl-2-cyclohexenyl)-3-buten-2-one; 4-acetoxy-3-methoxy-1-propenylbenzene; 2-propenyl cyclohexanepropionate; bicyclo[2.2.1]hept-5-ene-2-carboxylic acid, 3-(1-methylethyl)-ethyl ester; bycyclo[2.2.1]heptan-2-ol, 1,7,7-trimethyl-, acetate; 1,5-dimethyl-1-ethenylhex-4-enyl acetate; hexyl 2-methyl propanoate; ethyl-2-methylbutanoate, 4-undecanolide; 5-heptyldihydro-2(3h)-furanone; 5-hydroxydodecanoic acid; decalactones; undecalactones, 1,6-nonadien-3-ol, 3,7dimethyl-; 3,7-dimethylocta-1,6-dien-3-ol; 3-cyclohexene-1-carboxaldehyde, dimethyl-; 3,7-dimethyl-6-octene nitrile; 4-(2,6,6-trimethyl-1-cyclohexenyl)-3-buten-2-one; tridec-2-enonitrile; patchouli oil; ethyl tricycle [5.2.1.0]decan-2-carboxylate; 2,2-dimethyl-cyclohexanepropanol; allyl-cyclohexyloxy acetate; methyl nonyl acetic aldehyde; 1-spiro[4,5]dec-7-en-7-yl-4-pentenen-1-one; 7-octen-2-ol, 2-methyl-6-methylene-, dihydro, cyclohexanol, 2-(1,1-dimethylethyl)-, acetate; hexahydro-4,7-methanoinden-5(6)-yl propionatehexahydro-4,7-methanoinden-5(6)-yl propionate; 2-methoxynaphtalene; 1-(2,6,6-trimethyl-3-cyclohexenyl)-2-buten-1-one; 1-(2,6,6-trimethyl-2-cyclohexenyl)-2-buten-1-one; 3,7-dimethyloctan-3-ol; 3-buten-2-one, 3-methyl-4-(2,6,6-trimethyl-1-cyclohexen-2-yl)-; hexanoic acid, 2-propenyl ester; (z)-non-6-en-1-al; 1-decyl aldehyde; 1-octanal; 4-t-butyl-α-methylhydrocinnamaldehyde; ethyl-2,4-hexadienoate; 2-propenyl 3-cyclohexanepropanoate; and mixtures thereof; s.) a perfume composition comprising, based on total perfume composition weight, at least 5% of a material selected from the group consisting of 3-cyclohexene-1-carboxaldehyde, dimethyl-; 3-buten-2-one, 3-methyl-4-(2,6,6-trimethyl-1-cyclohexen-2-yl)-; patchouli oil; Hexanoic acid, 2-propenyl ester; 1-Octanal; 1-decyl aldehyde; (z)-non-6-en-1-al; methyl nonyl acetic aldehyde; ethyl-2-methylbutanoate; 1-methylethyl-2-methylbutanoate; ethyl-2-methyl pentanoate; 4-hydroxy-3-ethoxybenzaldehyde; 4-hydroxy-3-methoxybenzaldehyde; 3-hydroxy-2-methyl-4-pyrone; 3-hydroxy-2-ethyl-4-pyrone and mixtures thereof; t.) a perfume composition comprising, based on total perfume composition weight, less than 10% perfumes having a Clog P greater than 5.0; u.) a perfume composition comprising geranyl palmitate; or v.) a perfume composition comprising a first and an optional second material, said first material having:
(i) a Clog P of at least 2; (ii) a boiling point of less than about 280° C.; and
second optional second material, when present, having
(i) a Clog P of less than 2.5; and (ii) a ODT of less than about 100 ppb.
[0064] The perfume raw materials and accords may be obtained from one or more of the following companies Firmenich (Geneva, Switzerland), Givaudan (Argenteuil, France), IFF (Hazlet, N.J.), Quest (Mount Olive, N.J.), Bedoukian (Danbury, Conn.), Sigma Aldrich (St. Louis, Mo.), Millennium Specialty Chemicals (Olympia Fields, Ill.), Polarone International (Jersey City, N.J.), Fragrance Resources (Keyport, N.J.), and Aroma & Flavor Specialties (Danbury, Conn.).
Process of Making Benefit Agent Containing Delivery Particles
[0065] The particle disclosed in the present application may be made via the teachings of U.S. Pat. No. 6,592,990 B2 and/or U.S. Pat. No. 6,544,926 B1 and the examples disclosed herein.
[0066] Anionic emulsifiers are typically used during the particle making process to emulsify the benefit agent prior to microcapsule formation. While not being bound by theory, it is believed that the anionic materials adversely interact with the cationic surfactant actives that are often found in compositions such as fabric care compositions—this may yield an aesthetically unpleasing aggregation of particles that are employed in said composition. In addition to the unacceptable aesthetics, such aggregates may result in rapid phase separation of the particles from the bulk phase. Applicants discovered that such aggregates can be prevented by the addition of certain aggregate inhibiting materials including materials selected from the group consisting of salts, polymers and mixtures thereof. Useful aggregate inhibiting materials include, divalent salts such as magnesium salts, for example, magnesium chloride, magnesium acetate, magnesium phosphate, magnesium formate, magnesium boride, magnesium titanate, magnesium sulfate heptahydrate; calcium salts, for example, calcium chloride, calcium formate, calcium calcium acetate, calcium bromide; trivalent salts, such as aluminum salts, for example, aluminum sulfate, aluminum phosphate, aluminum chloride n-hydrate and polymers that have the ability to suspend anionic particles such as soil suspension polymers, for example, (polyethylene imines, alkoxylated polyethylene imines, polyquaternium-6 and polyquaternium-7.
[0067] In one aspect of the invention, benefit agent containing delivery particles are manufactured and are subsequently coated with a material to reduce the rate of leakage of the benefit agent from the particles when the particles are subjected to a bulk environment containing, for example, surfactants, polymers, and solvents. Non-limiting examples of coating materials that can serve as barrier materials include materials selected from the group consisting of polyvinyl pyrrolidone homopolymer, and its various copolymers with styrene, vinyl acetate, imidazole, primary and secondary amine containing monomers, methyl acrylate, polyvinyl acetal, maleic anhydride; polyvinyl alcohol homopolymer, and its various copolymers with vinyl acetate, 2-acrylamide-2-methylpropane sulfonate, primary and secondary amine containing monomers, imidazoles, methyl acrylate; polyacrylamides; polyacrylic acids; microcrystalline waxes; paraffin waxes; modified polysaccharides such as waxy maize or dent corn starch, octenyl succinated starches, derivatized starches such as hydroxyethylated or hydroxypropylated starches, carrageenan, guar gum, pectin, xanthan gum; modified celluloses such as hydrolyzed cellulose acetate, hydroxy propyl cellulose, methyl cellulose, and the like; modified proteins such as gelatin; hydrogenated and non-hydrogenated polyalkenes; fatty acids; hardened shells such as urea crosslinked with formaldehyde, gelatin-polyphosphate, melamine-formaldehyde, polyvinyl alcohol cross-linked with sodium tetraborate or gluteraldehyde; latexes of styrene-butadiene, ethyl cellulose, inorganic materials such as clays including magnesium silicates, aluminosilicates; sodium silicates, and the like; and mixtures thereof. Such materials can be obtained from CP Kelco Corp. of San Diego, Calif., USA; Degussa AG or Dusseldorf, Germany; BASF AG of Ludwigshafen, Germany; Rhodia Corp. of Cranbury, N.J., USA; Baker Hughes Corp. of Houston, Tex., USA; Hercules Corp. of Wilmington, Del., USA; Agrium Inc. of Calgary, Alberta, Canada, ISP of New Jersey U.S.A. In one aspect wherein the particle is employed in a fabric conditioning composition, the coating material comprises sodium silicate. While not being bound by theory, it is believed that sodium silicate's solubility at high pH, but poor solubility at low pH makes it an ideal material for use on particles that may be used in compositions that are formulated at pH below 7 but used in an environment wherein the pH is greater or equal to 7. The benefit agent containing delivery particles made be made by following the procedure described in U.S. Pat. No. 6,592,990. However, the coating aspect of the present invention is not limited to the benefit agent containing delivery particles of the present invention as any benefit agent containing delivery particle may benefit from the coatings and coating processes disclosed herein.
[0068] Suitable equipment for use in the processes disclosed herein may include continuous stirred tank reactors, homogenizers, turbine agitators, recirculating pumps, paddle mixers, plough shear mixers, ribbon blenders, vertical axis granulators and drum mixers, both in batch and, where available, in continuous process configurations, spray dryers, and extruders. Such equipment can be obtained from Lodige GmbH (Paderborn, Germany), Littleford Day, Inc. (Florence, Ky., U.S.A.), Forberg AS (Larvik, Norway), Glatt Ingenieurtechnik GmbH (Weimar, Germany), Niro (Soeborg, Denmark), Hosokawa Bepex Corp. (Minneapolis, Minn., USA), Arde Barinco (New Jersey, USA).
Formaldehyde Scavenging
[0069] In one aspect, benefit agent containing delivery particles may be combined with a formaldehyde scavenger. In one aspect, such benefit agent containing delivery particles may comprise the benefit agent containing delivery particles of the present invention. Suitable formaldehyde scavengers include materials selected from the group consisting of sodium bisulfite, urea, ethylene urea, cysteine, cysteamine, lysine, glycine, serine, carnosine, histidine, glutathione, 3,4-diaminobenzoic acid, allantoin, glycouril, anthranilic acid, methyl anthranilate, methyl 4-aminobenzoate, ethyl acetoacetate, acetoacetamide, malonamide, ascorbic acid, 1,3-dihydroxyacetone dimer, biuret, oxamide, benzoguanamine, pyroglutamic acid, pyrogallol, methyl gallate, ethyl gallate, propyl gallate, triethanol amine, succinamide, thiabendazole, benzotriazol, triazole, indoline, sulfanilic acid, oxamide, sorbitol, glucose, cellulose, poly(vinyl alcohol), partially hydrolyzed poly(vinylformamide), poly(vinyl amine), poly(ethylene imine), poly(oxyalkyleneamine), poly(vinyl alcohol)-co-poly(vinyl amine), poly(4-aminostyrene), poly(1-lysine), chitosan, hexane diol, ethylenediamine-N,N′-bisacetoacetamide, N-(2-ethylhexyl)acetoacetamide, 2-benzoylacetoacetamide, N-(3-phenylpropyl)acetoacetamide, lilial, helional, melonal, triplal, 5,5-dimethyl-1,3-cyclohexanedione, 2,4-dimethyl-3-cyclohexenecarboxaldehyde, 2,2-dimethyl-1,3-dioxan-4,6-dione, 2-pentanone, dibutyl amine, triethylenetetramine, ammonium hydroxide, benzylamine, hydroxycitronellol, cyclohexanone, 2-butanone, pentane dione, dehydroacetic acid, or a mixture thereof. These formaldehyde scavengers may be obtained from Sigma/Aldrich/Fluka of St. Louis, Mo. U.S.A. or PolySciences, Inc. of Warrington, Pa. U.S.A.
[0070] Such formaldehyde scavengers are typically combined with a slurry containing said benefit agent containing delivery particle, at a level, based on total slurry weight, of from about 2 wt. % to about 18 wt. %, from about 3.5 wt. % to about 14 wt. % or even from about 5 wt. % to about 13 wt. %.
[0071] In one aspect, such formaldehyde scavengers may be combined with a product containing a benefit agent containing delivery particle, said scavengers being combined with said product at a level, based on total product weight, of from about 0.005% to about 0.8%, alternatively from about 0.03% to about 0.5%, alternatively from about 0.065% to about 0.25% of the product formulation.
[0072] In another aspect, such formaldehyde scavengers may be combined with a slurry containing said benefit agent containing delivery particle, at a level, based on total slurry weight, of from about 2 wt. % to about 14 wt. %, from about 3.5 wt. % to about 14 wt. % or even from about 5 wt. % to about 14 wt. % and said slurry may be added to a product matrix to which addition an identical or different scavenger may be added at a level, based on total product weight, of from about 0.005% to about 0.5%, alternatively from about 0.01% to about 0.25%, alternatively from about 0.05% to about 0.15% of the product formulation.
[0073] In one aspect, one or more of the aforementioned formaldehyde scavengers may be combined with a liquid fabric enhancing product containing a benefit agent containing delivery particle at a level, based on total liquid fabric enhancing product weight, of from 0.005% to about 0.8%, alternatively from about 0.03% to about 0.4%, alternatively from about 0.06% to about 0.25% of the product formulation.
[0074] In one aspect, such formaldehyde scavengers may be combined with a liquid laundry detergent product containing a benefit agent containing delivery particle, said scavengers being selected from the group consisting of sodium bisulfite, urea, ethylene urea, cysteine, cysteamine, lysine, glycine, serine, carnosine, histidine, glutathione, 3,4-diaminobenzoic acid, allantoin, glycouril, anthranilic acid, methyl anthranilate, methyl 4-aminobenzoate, ethyl acetoacetate, acetoacetamide, malonamide, ascorbic acid, 1,3-dihydroxyacetone dimer, biuret, oxamide, benzoguanamine, pyroglutamic acid, pyrogallol, methyl gallate, ethyl gallate, propyl gallate, triethanol amine, succinamide, thiabendazole, benzotriazol, triazole, indoline, sulfanilic acid, oxamide, sorbitol, glucose, cellulose, poly(vinyl alcohol), partially hydrolyzed poly(vinylformamide), poly(vinyl amine), poly(ethylene imine), poly(oxyalkyleneamine), poly(vinyl alcohol)-co-poly(vinyl amine), poly(4-aminostyrene), poly(1-lysine), chitosan, hexane diol, ethylenediamine-N,N′-bisacetoacetamide, N-(2-ethylhexyl)acetoacetamide, 2-benzoylacetoacetamide, N-(3-phenylpropyl)acetoacetamide, lilial, helional, melonal, triplal, 5,5-dimethyl-1,3-cyclohexanedione, 2,4-dimethyl-3-cyclohexenecarboxaldehyde, 2,2-dimethyl-1,3-dioxan-4,6-dione, 2-pentanone, dibutyl amine, triethylenetetramine, ammonium hydroxide, benzylamine, hydroxycitronellol, cyclohexanone, 2-butanone, pentane dione, dehydroacetic acid and mixtures thereof, and combined with said liquid laundry detergent product at a level, based on total liquid laundry detergent product weight, of from about 0.003 wt. % to about 0.20 wt. %, from about 0.03 wt. % to about 0.20 wt. % or even from about 0.06 wt. % to about 0.14 wt. %.
[0075] In one aspect, such formaldehyde scavengers may be combined with a hair conditioning product containing a benefit agent containing delivery particle, at a level, based on total hair conditioning product weight, of from about 0.003 wt. % to about 0.30 wt. %, from about 0.03 wt. % to about 0.20 wt. % or even from about 0.06 wt. % to about 0.14 wt. %., said selection of scavengers being identical to the list of scavengers in the previous paragraph relating to a liquid laundry detergent product.
Compositions Comprising Benefit Agent Containing Delivery Particles
[0076] Applicants' compositions comprise an embodiment of the particle disclosed in the present application. In one aspect, said composition is a consumer product. While the precise level of particle that is employed depends on the type and end use of the composition, a composition may comprise from about 0.01 to about 10, from about 0.1 to about 10, or even from about 0.2 to about 5 weight % of said particle based on total composition weight. In one aspect, a cleaning composition may comprise, from about 0.1 to about 1 weight % of such particle based on total cleaning composition weight of such particle. In one aspect, a fabric treatment composition may comprise, based on total fabric treatment composition weight, form about 0.01 to about 10% of such particle.
[0077] Aspects of the invention include the use of the particles of the present invention in laundry detergent compositions (e.g., TIDE™), hard surface cleaners (e.g., MR CLEAN™), automatic dishwashing liquids (e.g., CASCADE™), dishwashing liquids (e.g., DAWN™), and floor cleaners (e.g., SWIFFER™). Non-limiting examples of cleaning compositions may include those described in U.S. Pat. Nos. 4,515,705; 4,537,706; 4,537,707; 4,550,862; 4,561,998; 4,597,898; 4,968,451; 5,565,145; 5,929,022; 6,294,514; and 6,376,445. The cleaning compositions disclosed herein are typically formulated such that, during use in aqueous cleaning operations, the wash water will have a pH of between about 6.5 and about 12, or between about 7.5 and 10.5. Liquid dishwashing product formulations typically have a pH between about 6.8 and about 9.0. Cleaning products are typically formulated to have a pH of from about 7 to about 12. Techniques for controlling pH at recommended usage levels include the use of buffers, alkalis, acids, etc., and are well known to those skilled in the art.
[0078] Fabric treatment compositions disclosed herein typically comprise a fabric softening active (“FSA”). Suitable fabric softening actives, include, but are not limited to, materials selected from the group consisting of quats, amines, fatty esters, sucrose esters, silicones, dispersible polyolefins, clays, polysaccharides, fatty oils, polymer latexes and mixtures thereof.
Adjunct Materials
[0079] While not essential for the purposes of the present invention, the non-limiting list of adjuncts illustrated hereinafter are suitable for use in the instant compositions and may be desirably incorporated in certain embodiments of the invention, for example to assist or enhance performance, for treatment of the substrate to be cleaned, or to modify the aesthetics of the composition as is the case with perfumes, colorants, dyes or the like. It is understood that such adjuncts are in addition to the components that are supplied via Applicants' delivery particles and FSAs. The precise nature of these additional components, and levels of incorporation thereof, will depend on the physical form of the composition and the nature of the operation for which it is to be used. Suitable adjunct materials include, but are not limited to, polymers, for example cationic polymers, surfactants, builders, chelating agents, dye transfer inhibiting agents, dispersants, enzymes, and enzyme stabilizers, catalytic materials, bleach activators, polymeric dispersing agents, clay soil removal/anti-redeposition agents, brighteners, suds suppressors, dyes, additional perfume and perfume delivery systems, structure elasticizing agents, fabric softeners, carriers, hydrotropes, processing aids and/or pigments. In addition to the disclosure below, suitable examples of such other adjuncts and levels of use are found in U.S. Pat. Nos. 5,576,282, 6,306,812 B1 and 6,326,348 B1 that are incorporated by reference.
[0080] As stated, the adjunct ingredients are not essential to Applicants' cleaning and fabric care compositions. Thus, certain embodiments of Applicants' compositions do not contain one or more of the following adjuncts materials: bleach activators, surfactants, builders, chelating agents, dye transfer inhibiting agents, dispersants, enzymes, and enzyme stabilizers, catalytic metal complexes, polymeric dispersing agents, clay and soil removal/anti-redeposition agents, brighteners, suds suppressors, dyes, additional perfumes and perfume delivery systems, structure elasticizing agents, fabric softeners, carriers, hydrotropes, processing aids and/or pigments. However, when one or more adjuncts are present, such one or more adjuncts may be present as detailed below:
[0081] Surfactants—The compositions according to the present invention can comprise a surfactant or surfactant system wherein the surfactant can be selected from nonionic and/or anionic and/or cationic surfactants and/or ampholytic and/or zwitterionic and/or semi-polar nonionic surfactants. The surfactant is typically present at a level of from about 0.1%, from about 1%, or even from about 5% by weight of the cleaning compositions to about 99.9%, to about 80%, to about 35%, or even to about 30% by weight of the cleaning compositions.
[0082] Builders—The compositions of the present invention can comprise one or more detergent builders or builder systems. When present, the compositions will typically comprise at least about 1% builder, or from about 5% or 10% to about 80%, 50%, or even 30% by weight, of said builder. Builders include, but are not limited to, the alkali metal, ammonium and alkanolammonium salts of polyphosphates, alkali metal silicates, alkaline earth and alkali metal carbonates, aluminosilicate builders polycarboxylate compounds. ether hydroxypolycarboxylates, copolymers of maleic anhydride with ethylene or vinyl methyl ether, 1,3,5-trihydroxybenzene-2,4,6-trisulphonic acid, and carboxymethyl-oxysuccinic acid, the various alkali metal, ammonium and substituted ammonium salts of polyacetic acids such as ethylenediamine tetraacetic acid and nitrilotriacetic acid, as well as polycarboxylates such as mellitic acid, succinic acid, oxydisuccinic acid, polymaleic acid, benzene 1,3,5-tricarboxylic acid, carboxymethyloxysuccinic acid, and soluble salts thereof.
[0083] Chelating Agents—The compositions herein may also optionally contain one or more copper, iron and/or manganese chelating agents. If utilized, chelating agents will generally comprise from about 0.1% by weight of the compositions herein to about 15%, or even from about 3.0% to about 15% by weight of the compositions herein.
[0084] Dye Transfer Inhibiting Agents—The compositions of the present invention may also include one or more dye transfer inhibiting agents. Suitable polymeric dye transfer inhibiting agents include, but are not limited to, polyvinylpyrrolidone polymers, polyamine N-oxide polymers, copolymers of N-vinylpyrrolidone and N-vinylimidazole, polyvinyloxazolidones and polyvinylimidazoles or mixtures thereof. When present in the compositions herein, the dye transfer inhibiting agents are present at levels from about 0.0001%, from about 0.01%, from about 0.05% by weight of the cleaning compositions to about 10%, about 2%, or even about 1% by weight of the cleaning compositions.
[0085] Dispersants—The compositions of the present invention can also contain dispersants. Suitable water-soluble organic materials are the homo- or co-polymeric acids or their salts, in which the polycarboxylic acid may comprise at least two carboxyl radicals separated from each other by not more than two carbon atoms.
[0086] Enzymes—The compositions can comprise one or more detergent enzymes which provide cleaning performance and/or fabric care benefits. Examples of suitable enzymes include, but are not limited to, hemicellulases, peroxidases, proteases, cellulases, xylanases, lipases, phospholipases, esterases, cutinases, pectinases, keratanases, reductases, oxidases, phenoloxidases, lipoxygenases, ligninases, pullulanases, tannases, pentosanases, malanases, β-glucanases, arabinosidases, hyaluronidase, chondroitinase, laccase, and amylases, or mixtures thereof. A typical combination is a cocktail of conventional applicable enzymes like protease, lipase, cutinase and/or cellulase in conjunction with amylase.
[0087] Enzyme Stabilizers—Enzymes for use in compositions, for example, detergents can be stabilized by various techniques. The enzymes employed herein can be stabilized by the presence of water-soluble sources of calcium and/or magnesium ions in the finished compositions that provide such ions to the enzymes.
[0088] Catalytic Metal Complexes—Applicants' compositions may include catalytic metal complexes. One type of metal-containing bleach catalyst is a catalyst system comprising a transition metal cation of defined bleach catalytic activity, such as copper, iron, titanium, ruthenium, tungsten, molybdenum, or manganese cations, an auxiliary metal cation having little or no bleach catalytic activity, such as zinc or aluminum cations, and a sequestrate having defined stability constants for the catalytic and auxiliary metal cations, particularly ethylenediaminetetraacetic acid, ethylenediaminetetra (methyl-enephosphonic acid) and water-soluble salts thereof. Such catalysts are disclosed in U.S. Pat. No. 4,430,243.
[0089] If desired, the compositions herein can be catalyzed by means of a manganese compound. Such compounds and levels of use are well known in the art and include, for example, the manganese-based catalysts disclosed in U.S. Pat. No. 5,576,282.
[0090] Cobalt bleach catalysts useful herein are known, and are described, for example, in U.S. Pat. Nos. 5,597,936 and 5,595,967. Such cobalt catalysts are readily prepared by known procedures, such as taught for example in U.S. Pat. Nos. 5,597,936, and 5,595,967.
[0091] Compositions herein may also suitably include a transition metal complex of a macropolycyclic rigid ligand—abbreviated as “MRL”. As a practical matter, and not by way of limitation, the compositions and cleaning processes herein can be adjusted to provide on the order of at least one part per hundred million of the benefit agent MRL species in the aqueous washing medium, and may provide from about 0.005 ppm to about 25 ppm, from about 0.05 ppm to about 10 ppm, or even from about 0.1 ppm to about 5 ppm, of the MRL in the wash liquor.
[0092] Preferred transition-metals in the instant transition-metal bleach catalyst include manganese, iron and chromium. Preferred MRL's herein are a special type of ultra-rigid ligand that is cross-bridged such as 5,12-diethyl-1,5,8,12-tetraazabicyclo[6.6.2]hexa-decane.
[0093] Suitable transition metal MRLs are readily prepared by known procedures, such as taught for example in WO 00/32601, and U.S. Pat. No. 6,225,464.
Processes of Making and Using Compositions
[0094] The compositions of the present invention can be formulated into any suitable form and prepared by any process chosen by the formulator, non-limiting examples of which are described in U.S. Pat. No. 5,879,584; U.S. Pat. No. 5,691,297; U.S. Pat. No. 5,574,005; U.S. Pat. No. 5,569,645; U.S. Pat. No. 5,565,422; U.S. Pat. No. 5,516,448; U.S. Pat. No. 5,489,392; U.S. Pat. No. 5,486,303 all of which are incorporated herein by reference.
Method of Use
[0095] Compositions containing the benefit agent delivery particle disclosed herein can be used to clean or treat a situs inter alia a surface or fabric. Typically at least a portion of the situs is contacted with an embodiment of Applicants' composition, in neat form or diluted in a liquor or dispersed in a binder material, for example, a wash liquor, or a dispersed particle composition and binder. The situs may be optionally washed and/or rinsed before and/or after contact. In one aspect, a situs is optionally washed and/or rinsed, contacted with a particle according to the present invention or composition comprising said particle and then optionally washed and/or rinsed. For purposes of the present invention, washing includes but is not limited to, scrubbing, and mechanical agitation. The fabric may comprise most any fabric capable of being laundered or treated in normal consumer use conditions. Liquors that may comprise the disclosed compositions may have a pH of from about 3 to about 11.5. Such compositions are typically employed at concentrations of from about 500 ppm to about 15,000 ppm in solution. When the wash solvent is water, the water temperature typically ranges from about 5° C. to about 90° C. and, when the situs comprises a fabric, the water to fabric ratio is typically from about 1:1 to about 30:1.
[0096] When the particle composition comprises particles dispersed in binder, the dispersed particle composition and binder can be dried or cured on the situs. A releasing force such as pressure, friction, heat, actinic radiation, laser light, electromagnetic radiation, chemical degradation, or ultrasonics can be used to release the core contents from the particles.
[0097] Some applications employ parts per million of particles to binder where trace amounts of core are sufficient for the application. In other applications such compositions are employed at concentration of from 0.001% by weight of the composition to 90% by weight capsules in a slurry of capsules and binder. Binder can be used at a ratio of particles to binder at from 3:1 to about 0.0001 to 1 by weight depending on the intended application. When the situs comprises a polymeric substrate the capsules are used at a ratio of from 1.5:1 and preferably a range from 0.001:1 to 1.2:1. With a heavier paper surface, the particles and binder can be applied at a coat rate of from 2.5 to 12 grams per square meter, preferably 3 to 9 gsm. with the particles being at from 0.001 to 75% of the coating by weight.
Test Methods
[0098] It is understood that the test methods that are disclosed in the Test Methods Section of the present application should be used to determine the respective values of the parameters of Applicants' invention as such invention is described and claimed herein.
[0099] (1) Fracture Strength
a.) Place 1 gram of particles in 1 liter of distilled deionized (DI) water. b.) Permit the particles to remain in the DI water for 10 minutes and then recover the particles by filtration. c.) Determine the average rupture force of the particles by averaging the rupture force of 50 individual particles. The rupture force of a particle is determined using the procedure given in Zhang, Z.; Sun, G; “Mechanical Properties of Melamine-Formaldehyde microcapsules,” J. Microencapsulation, vol 18, no. 5, pages 593-602, 2001. Then calculate the average fracture strength by dividing the average rupture force (in Newtons) by the average cross-sectional area of the spherical particle (πr 2 , where r is the radius of the particle before compression), said average cross-sectional area being determined as follows:
(i) Place 1 gram of particles in 1 liter of distilled deionized (DI) water. (ii) Permit the particles to remain in the DI water for 10 minutes and then recover the particles by filtration. (iii) Determine the particle size distribution of the particle sample by measuring the particle size of 50 individual particles using the experimental apparatus and method of Zhang, Z.; Sun, G; “Mechanical Properties of Melamine-Formaldehyde microcapsules,” J. Microencapsulation, vol 18, no. 5, pages 593-602, 2001. (iv) Average the 50 independent particle diameter measurements to obtain an average particle diameter.
d) For a capsule slurry the sample is divided into three particle size fractions covering the particle size distribution. Per particle size fraction about 30 fracture strengths are determined.
[0108] (2) ClogP
The “calculated logP” (ClogP) is determined by the fragment approach of Hansch and Leo (cf., A. Leo, in Comprehensive Medicinal Chemistry, Vol. 4, C. Hansch, P. G. Sammens, J. B. Taylor, and C. A. Ramsden, Eds. P. 295, Pergamon Press, 1990, incorporated herein by reference). ClogP values may be calculated by using the “CLOGP” program available from Daylight Chemical Information Systems Inc. of Irvine, Calif. U.S.A.
[0110] (3) Boiling Point
Boiling point is measured by ASTM method D2887-04a, “Standard Test Method for Boiling Range Distribution of Petroleum Fractions by Gas Chromatography,” ASTM International.
[0112] (4) Volume Weight Fractions
Volume weight fractions are determined via the method of single-particle optical sensing (SPOS), also called optical particle counting (OPC). Volume weight fractions are determined via a AccuSizer 780/AD supplied by Particle Sizing Systems of Santa Barbara Calif., U.S.A.
[0114] Procedure:
1) put the sensor in a cold state by flushing water through the sensor 2) confirm background counts are less than 100 (if got more than 100, continue the flush) 3) prepare particle standard: pipette approx. 1 ml of shaken particles into blender filled with approx. 2 cups of DI water. Blend it. Pipette approx. 1 ml of diluted blended particles into 50 ml DI water. 4) measure particle standard: pipette approx. 1 ml of double diluted standard into Accusizer bulb. Press the start measurement-Autodilution button. Confirm particles counts are more than 9200 by looking in the status bar. If counts are less than 9200, press stop and inject more sample. 5) immediately after measurement, inject one full pipette of soap (5% Micro 90) into bulb and press the Start Automatic Flush Cycles button.
[0120] (5) Volume Weighted Fracture Strength (VWFS)
[0000] VWFS =(fracture strength 1 ×volume fraction 1 )+(fracture strength 2 ×volume fraction 2 )+(fracture strength 3 ×volume fraction 3 ) Fracture strength 1 =average fracture strength measured from a pool of 10 microcapsules (with similar particle size) Volume fraction 1 =volume fraction determined via Accusizer of particle distribution corresponding to fracture strength 1 The spread around the fracture strength to determine the volume fraction is determined as follows: For particle batches with a mean particle sizes of about 15 um a spread of about 10 um is used, for particle batches with a mean particle sizes of about 30 um and above, a spread of about 10 to 15 um is used
[0125] Examples
[0000]
Fracture Strength
Volume
Particle
Mean Particle
Determination at
Volume
Fracture
batch
Size
3 particle sizes
Fractions
Strength
Melamine
31micron
21 micron:
1 to
1.5
based
1.8 MPa
25 micron
MPa
polyurea
31 micron: 1.6 MPa
30%
41 micron: 1.2 MPa
25 to 36
micron 40%
36 to 50
micron 30%
[0126] (6) Benefit Agent Leakage Test
a.) Obtain 2, one gram samples of benefit agent particle composition. b.) Add 1 gram (Sample 1) of particle composition to 99 grams of product matrix that the particle will be employed in and with the second sample immediately proceed to Step d below. c.) Age the particle containing product matrix (Sample 1) of a.) above for 2 weeks at 35° C. in a sealed, glass jar. d.) Recover the particle composition's particles from the product matrix of c.) (Sample 1 in product matrix) and from particle composition (Sample 2) above by filtration. e.) Treat each particle sample from d.) above with a solvent that will extract all the benefit agent from each samples' particles. f.) Inject the benefit agent containing solvent from each sample from e.) above into a Gas Chromatograph and integrate the peak areas to determine the total quantity of benefit agent extracted from each sample. g.) The benefit agent leakage is defined as:
Value from f.) above for Sample 2−Value from f.) above for Sample 1.
EXAMPLES
[0135] While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.
Example 1
80 Wt % Core/20 Wt % Wall Urea Based Polyurea Capsule
[0136] 2 grams of Urea (Sigma Aldrich of Milwaukee, Wis.) is dissolved in 20 g deionized water. 1 gram of resorcinol (Sigma Aldrich of Milwaukee, Wis.) is added to the homogeneous urea solution. 20 g of 37 wt % formaldehyde solution (Sigma Aldrich of Milwaukee, Wis.) is added to the solution, and the pH of the slurry is adjusted to 8.0 using 1M sodium hydroxide solution (Sigma Aldrich of Milwaukee, Wis.). The reactants are allowed to sit at 35° C. for 2 hours. In a separate beaker, 80 grams of fragrance oil is added slowly to the urea-formaldehyde solution. The mixture is agitated using a Janke & Kunkel Laboretechnik mixer using a pitched, 3-blade agitator to achieve a 31 micron mean oil droplet size distribution. The pH of the slurry is adjusted to 3.0 using 1M Hydrochloric Acid to initiate the condensation reaction. The solution is heated to 65° C. and allowed to react in a constant temperature water bath, while slowly agitating the contents of the mixture. The contents are allowed to react for 4 hours at 65° C.
[0137] The Volume Average Fracture Strength Fracture is determined to be 1.5 MPa.
Example 2
85% Core/15 Wt % Wall Melamine Based Polyurea Capsule
[0138] A first mixture is prepared by combining 208 grams of water and 5 grams of alkyl acrylate-acrylic acid copolymer (Polysciences, Inc. of Warrington, Pa., USA). This first mixture is adjusted to pH 5.0 using acetic acid.
[0139] 178 grams of the capsule core material which comprise a fragrance oil is added to the first mixture at a temperature of 45° C. to form an emulsion. The ingredients to form the capsule wall material are prepared as follows: 9 grams of a corresponding capsule wall material copolymer pre-polymer (butylacrylate-acrylic acid copolymer) and 90 grams of water are combined and adjusted to pH 5.0. To this mixture is added 28 grams of a partially methylated methylol melamine resin solution (“Cymel 385”, 80% solids, Cytec). This mixture is added to the above described fragrance oil-in-water emulsion with stirring at a temperature of 45 degrees Centigrade. High speed blending is used to achieve a volume-mean particle size of 16 micron. The temperature of the mixture is gradually raised to 65 degrees Centigrade, and is maintained at this temperature overnight with continuous stirring to initiate and complete encapsulation.
[0140] To form the acrylic acid-alkyl acrylate copolymer capsule wall, the alkyl group can be selected from ethyl, propyl, butyl, amyl, hexyl, cyclohexyl, 2-ethylhexyl, or other alkyl groups having from one to about sixteen carbons, preferably one to eight carbons.
[0141] The Volume Average Fracture Strength Fracture is determined to be 3.3 MPa.
Example 3
90% Core/10 Wt % Wall Melamine Based Polyurea Capsule
[0142] A first mixture is prepared by combining 208 grams of water and 5 grams of alkyl acrylate-acrylic acid copolymer (Polysciences, Inc. of Warrington, Pa., USA). This first mixture is adjusted to pH 5.0 using acetic acid.
[0143] 280 grams of the capsule core material which comprise a fragrance oil is added to the first mixture at a temperature of 45° C. to form an emulsion. The ingredients to form the capsule wall material are prepared as follows: 9 grams of a corresponding capsule wall material copolymer pre-polymer (butylacrylate-acrylic acid copolymer) and 90 grams of water are combined and adjusted to pH 5.0. To this mixture is added 28 grams of a partially methylated methylol melamine resin solution (“Cymel 385”, 80% solids, Cytec). This mixture is added to the above described fragrance oil-in-water emulsion with stirring at a temperature of 45 degrees Centigrade. High speed blending is used to achieve a volume-mean particle size of 18 micron. The temperature of the mixture is gradually raised to 65 degrees Centigrade, and is maintained at this temperature overnight with continuous stirring to initiate and complete encapsulation.
[0144] To form the acrylic acid-alkyl acrylate copolymer capsule wall, the alkyl group can be selected from ethyl, propyl, butyl, amyl, hexyl, cyclohexyl, 2-ethylhexyl, or other alkyl groups having from one to about sixteen carbons, preferably one to eight carbons.
[0145] The Volume Average Fracture Strength Fracture is determined to be 0.5 MPa.
Example 4
80% Core/20 Wt % Wall Melamine Based Polyurea Capsule
[0146] A first mixture is prepared by combining 208 grams of water and 5 grams of alkyl acrylate-acrylic acid copolymer (Polysciences, Inc. of Warrington, Pa., USA). This first mixture is adjusted to pH 5.0 using acetic acid.
[0147] 125 grams of the capsule core material which comprises a fragrance oil is added to the first mixture at a temperature of 45° C. to form an emulsion. The ingredients to form the capsule wall material are prepared as follows: 9 grams of a corresponding capsule wall material copolymer pre-polymer (butylacrylate-acrylic acid copolymer) and 90 grams of water are combined and adjusted to pH 5.0. To this mixture is added 28 grams of a partially methylated methylol melamine resin solution (“Cymel 385”, 80% solids, Cytec). This mixture is added to the above described fragrance oil-in-water emulsion with stirring at a temperature of 45 degrees Centigrade. High speed blending is used to achieve a volume-mean particle size of 15 micron. The temperature of the mixture is gradually raised to 65 degrees Centigrade, and is maintained at this temperature overnight with continuous stirring to initiate and complete encapsulation.
[0148] To form the acrylic acid-alkyl acrylate copolymer capsule wall, the alkyl group can be selected from ethyl, propyl, butyl, amyl, hexyl, cyclohexyl, 2-ethylhexyl, or other alkyl groups having from one to about sixteen carbons, preferably one to eight carbons.
[0149] The Volume Average Fracture Strength Fracture is determined to be 9.5 MPa.
Example 5
85% Core/15 Wt % Wall Melamine Based Polyurea Capsule
[0150] A first mixture is prepared by combining 208 grams of water and 5 grams of alkyl acrylate-acrylic acid copolymer (Polysciences, Inc. of Warrington, Pa., USA). This first mixture is adjusted to pH 5.0 using acetic acid.
[0151] 178 grams of the capsule core material which comprise a fragrance oil is added to the first mixture at a temperature of 45° C. to form an emulsion. The ingredients to form the capsule wall material are prepared as follows: 9 grams of a corresponding capsule wall material copolymer pre-polymer (butylacrylate-acrylic acid copolymer) and 90 grams of water are combined and adjusted to pH 5.0. To this mixture is added 28 grams of a partially methylated methylol melamine resin solution (“Cymel 385”, 80% solids, Cytec). This mixture is added to the above described fragrance oil-in-water emulsion with stirring at a temperature of 45 degrees Centigrade. High speed blending is used to achieve a volume-mean particle size of 15 microns. The temperature of the mixture is gradually raised to 65 degrees Centigrade, and is maintained at this temperature overnight with continuous stirring to initiate and complete encapsulation.
[0152] To form the acrylic acid-alkyl acrylate copolymer capsule wall, the alkyl group can be selected from ethyl, propyl, butyl, amyl, hexyl, cyclohexyl, 2-ethylhexyl, or other alkyl groups having from one to about sixteen carbons, preferably one to eight carbons.
[0153] The Volume Average Fracture Strength Fracture is determined to be 15.1 MPa.
Example 6
80 Wt % Core/20 Wt % Wall Melamine Formaldehyde Capsule
[0154] 18 grams of a blend of 50% butyl acrylate-acrylic acid copolymer emulsifier (Colloid C351, 25% solids, pka 4.5-4.7, Kemira) and 50% polyacrylic acid (35% solids, pKa 1.5-2.5, Aldrich) is dissolved and mixed in 200 grams deionized water. The pH of the solution is adjusted to pH of 3.5 with sodium hydroxide solution. 6.5 grams of partially methylated methylol melamine resin (Cymel 385, 80% solids Cytec) is added to the emulsifier solution. 200 grams of perfume oil is added to the previous mixture under mechanical agitation and the temperature is raised to 60° C. After mixing at higher speed until a stable emulsion is obtained, the second solution and 3.5 grams of sodium sulfate salt are poured into the emulsion. This second solution contains 10 grams of butyl acrylate-acrylic acid copolymer emulsifier (Colloid C351, 25% solids, pka 4.5-4.7, Kemira), 120 grams of distilled water, sodium hydroxide solution to adjust pH to 4.6, 30 grams of partially methylated methylol melamine resin (Cymel 385, 80% Cytec). This mixture is heated to 75° C. and maintained 6 hours with continuous stirring to complete the encapsulation process. 23 grams of acetoacetamide (Sigma-Aldrich, Saint Louis, Mo., U.S.A.) is added to the suspension.
Example 7
80 Wt % Core/20 Wt % Wall Melamine Formaldehyde Capsule
[0155] 20 grams of butyl acrylate-acrylic acid copolymer emulsifier (Colloid C351, 25% solids, pKa 4.5-4.7, Kemira) is dissolved and mixed in 200 grams deionized water. The pH of the solution is adjusted to pH of 5.5 with sodium hydroxide solution. 6 grams of partially methylated methylol melamine resin (Cymel 385, 80% solids, Cytec) is added to the emulsifier solution. 200 grams of perfume oil is added to the previous mixture under mechanical agitation and the temperature is raised to 55° C. After mixing at higher speed until a stable emulsion is obtained, the second solution and 9 grams of sodium sulfate salt is added to the emulsion. This second solution contains 8 grams of polyacrylic acid (35% solids, pka 1.5-2.5, Aldrich), 120 grams of distilled water, sodium hydroxide solution to adjust pH to 4.4, 35 grams of partially methylated methylol melamine resin (Cymel 385, 80% solids, Cytec). This mixture is heated to 80° C. and maintained 4 hours with continuous stirring to complete the encapsulation process. 23 grams of acetoacetamide (Sigma-Aldrich, Saint Louis, Mo., U.S.A.) is added to the suspension.
Example 8
[0156] Non-limiting examples of product formulations containing microcapsules summarized in the following table.
[0000]
EXAMPLES
(% wt)
XI
XII
XIII
XIV
XV
XVI
XVII
XVIII
XIX
XX
FSA a
14
16.47
14
12
12
16.47
—
—
5
5
FSA b
—
3.00
—
—
—
FSA c
—
—
6.5
—
—
Ethanol
2.18
2.57
2.18
1.95
1.95
2.57
—
—
0.81
0.81
Isopropyl
—
—
—
—
—
—
0.33
1.22
—
—
Alcohol
Starch d
1.25
1.47
2.00
1.25
—
2.30
0.5
0.70
0.71
0.42
Microcapsule
0.6
0.75
0.6
0.75
0.37
0.60
0.37
0.6
0.37
0.37
(%
active)*
Formaldehyde
0.40
0.13
0.065
0.25
0.03
0.030
0.030
0.065
0.03
0.03
Scavenger e
Phase
0.21
0.25
0.21
0.21
0.14
—
—
0.14
—
—
Stabilizing
Polymer f
Suds
—
—
—
—
—
—
—
0.1
—
—
Suppressor g
Calcium
0.15
0.176
0.15
0.15
0.30
0.176
—
0.1-0.15
—
—
Chloride
DTPA h
0.017
0.017
0.017
0.017
0.007
0.007
0.20
—
0.002
0.002
Preservative
5
5
5
5
5
5
—
250 j
5
5
(ppm) i,j
Antifoam k
0.015
0.018
0.015
0.015
0.015
0.015
—
—
0.015
0.015
Dye
40
40
40
40
40
40
11
30-300
30
30
(ppm)
Ammonium
0.100
0.118
0.100
0.100
0.115
0.115
—
—
—
—
Chloride
HCl
0.012
0.014
0.012
0.012
0.028
0.028
0.016
0.025
0.011
0.011
Structurant l
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01
0.01
Neat
0.8
0.7
0.9
0.5
1.2
0.5
1.1
0.6
1.0
0.9
Unencapsulated
Perfume
Deionized
Balance
Balance
Balance
Balance
Balance
Balance
Balance
Balance
Balance
Balance
Water
a N,N-di(tallowoyloxyethyl)-N,N-dimethylammonium chloride.
b Methyl bis(tallow amidoethyl)2-hydroxyethyl ammonium methyl sulfate.
c Reaction product of Fatty acid with Methyldiethanolamine in a molar ratio 1.5:1, quaternized with Methylchloride, resulting in a 1:1 molar mixture of N,N-bis(stearoyl-oxy-ethyl) N,N-dimethyl ammonium chloride and N-(stearoyl-oxy-ethyl) N,-hydroxyethyl N,N dimethyl ammonium chloride.
d Cationic high amylose maize starch available from National Starch under the trade name CATO ®.
e The formaldehyde scavenger is acetoacetamide available from Aldrich.
f Copolymer of ethylene oxide and terephthalate having the formula described in U.S. Pat. No. 5,574,179 at col. 15, lines 1-5, wherein each X is methyl, each n is 40, u is 4, each R1 is essentially 1,4-phenylene moieties, each R2 is essentially ethylene, 1,2-propylene moieties, or mixtures thereof.
g SE39 from Wacker
h Diethylenetriaminepentaacetic acid.
i KATHON ® CG available from Rohm and Haas Co. “PPM” is “parts per million.”
j Gluteraldehyde
k Silicone antifoam agent available from Dow Corning Corp. under the trade name DC2310.
l Hydrophobically-modified ethoxylated urethane available from Rohm and Haas under the tradename Aculan 44.
*Suitable combinations of the microcapsules provided in Examples 1 through 7.
Example 9
Microcapsules in Dry Laundry Formulations
[0157]
[0000]
% w/w granular laundry detergent composition
Component
A
B
C
D
E
F
G
Brightener
0.1
0.1
0.1
0.2
0.1
0.2
0.1
Soap
0.6
0.6
0.6
0.6
0.6
0.6
0.6
Ethylenediamine disuccinic acid
0.1
0.1
0.1
0.1
0.1
0.1
0.1
Acrylate/maleate copolymer
1.5
1.5
1.5
1.5
1.5
1.5
1.5
Hydroxyethane di(methylene
0.4
0.4
0.4
0.4
0.4
0.4
0.4
phosphonic acid)
Mono-C 12-14 alkyl, di-methyl,
0.5
0.5
0.5
0.5
0.5
0.5
0.5
mono-hydroyethyl quaternary
ammonium chloride
Linear alkyl benzene
0.1
0.1
0.2
0.1
0.1
0.2
0.1
Linear alkyl benzene sulphonate
10.3
10.1
19.9
14.7
10.3
17
10.5
Magnesium sulphate
0.4
0.4
0.4
0.4
0.4
0.4
0.4
Sodium carbonate
19.5
19.2
10.1
18.5
29.9
10.1
16.8
Sodium sulphate
29.6
29.8
38.8
15.1
24.4
19.7
19.1
Sodium Chloride
0.1
0.1
0.1
0.1
0.1
0.1
0.1
Zeolite
9.6
9.4
8.1
18
10
13.2
17.3
Photobleach particle
0.1
0.1
0.2
0.1
0.2
0.1
0.2
Blue and red carbonate speckles
1.8
1.8
1.8
1.8
1.8
1.8
1.8
Ethoxylated Alcohol AE7
1
1
1
1
1
1
1
Tetraacetyl ethylene diamine
0.9
0.9
0.9
0.9
0.9
0.9
0.9
agglomerate (92 wt % active)
Citric acid
1.4
1.4
1.4
1.4
1.4
1.4
1.4
PDMS/clay agglomerates (9.5%
10.5
10.3
5
15
5.1
7.3
10.2
wt % active PDMS)
Polyethylene oxide
0.2
0.2
0.2
0.2
0.2
0.2
0.2
Enzymes e.g. Protease (84 mg/g
0.2
0.3
0.2
0.1
0.2
0.1
0.2
active), Amylase (22 mg/g active)
Suds suppressor agglomerate
0.2
0.2
0.2
0.2
0.2
0.2
0.2
(12.4 wt % active)
Sodium percarbonate (having
7.2
7.1
4.9
5.4
6.9
19.3
13.1
from 12% to 15% active AvOx)
Perfume oil
0.5
0.5
0.5
0.5
0.5
0.5
0.5
Solid perfume particles
0.4
0
0.4
0.4
0.4
0.4
0.6
Perfume microcapsules*
1.3
2.4
1
1.3
1.3
1.3
0.7
Water
1.4
1.4
1.4
1.4
1.4
1.4
1.4
Misc
0.1
0.1
0.1
0.1
0.1
0.1
0.1
Total Parts
100
100
100
100
100
100
100
*Microcapsule added as 35% active slurry. Core/wall ratio can range from 80/20 up to 90/10 and average particle diameter can range from 5 μm to 50 μm
Example 10
Liquid Laundry Formulations (HDLs)
[0158]
[0000]
Ingredient
HDL 1
HDL 2
HDL 3
HDL 4
HDL 5
HDL 6
Alkyl Ether Sulphate
0.00
0.50
12.0
12.0
6.0
7.0
Dodecyl Benzene
8.0
8.0
1.0
1.0
2.0
3.0
Sulphonic Acid
Ethoxylated Alcohol
8.0
6.0
5.0
7.0
5.0
3.0
Citric Acid
5.0
3.0
3.0
5.0
2.0
3.0
Fatty Acid
3.0
5.0
5.0
3.0
6.0
5.0
Ethoxysulfated
1.9
1.2
1.5
2.0
1.0
1.0
hexamethylene diamine
quaternized
Diethylene triamine penta
0.3
0.2
0.2
0.3
0.1
0.2
methylene phosphonic acid
Enzymes
1.20
0.80
0
1.2
0
0.8
Brightener (disulphonated
0.14
0.09
0
0.14
0.01
0.09
diamino stilbene based
FWA)
Cationic hydroxyethyl
0
0
0.10
0
0.200
0.30
cellulose
Poly(acrylamide-co-
0
0
0
0.50
0.10
0
diallyldimethylammonium
chloride)
Hydrogenated Castor Oil
0.50
0.44
0.2
0.2
0.3
0.3
Structurant
Boric acid
2.4
1.5
1.0
2.4
1.0
1.5
Ethanol
0.50
1.0
2.0
2.0
1.0
1.0
1,2 propanediol
2.0
3.0
1.0
1.0
0.01
0.01
Glutaraldehyde
0
0
19 ppm
0
13 ppm
0
Diethyleneglycol (DEG)
1.6
0
0
0
0
0
2,3-Methyl-1,3-
1.0
1.0
0
0
0
0
propanediol (M pdiol)
Mono Ethanol Amine
1.0
0.5
0
0
0
0
NaOH Sufficient To
pH 8
pH 8
pH 8
pH 8
pH 8
pH 8
Provide Formulation pH of:
Sodium Cumene
2.00
0
0
0
0
0
Sulphonate (NaCS)
Silicone (PDMS) emulsion
0.003
0.003
0.003
0.003
0.003
0.003
Perfume
0.7
0.5
0.8
0.8
0.6
0.6
Polyethyleneimine
0.01
0.10
0.00
0.10
0.20
0.05
Perfume Microcapsules*
1.00
5.00
1.00
2.00
0.10
0.80
Water
Balance
Balance
Balance
Balance
Balance
Balance
to
to
to
to
to
to
100%
100%
100%
100%
100%
100%
*Perfume Microcapsules in accordance with the teaching of the present specification.
[0159] The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about 40 mm”.
[0160] All documents cited in the Detailed Description of the Invention are, in relevant part, incorporated herein by reference; the citation of any document is not to be construed as an admission that it is prior art with respect to the present invention. To the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.
[0161] While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention. | The present invention relates to benefit agent containing delivery particles, compositions comprising said particles, and processes for making and using the aforementioned particles and compositions. When employed in compositions, for example, compositions for cleaning, fabric care, or coating onto various substrates, textiles or surfaces, such particles increase the efficiency of benefit agent delivery, thereby allowing reduced amounts of benefit agents to be employed. In addition to allowing the amount of benefit agent to be reduced, such particles allow a broad range of benefit agents to be employed. | 0 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application No. 60/223,950, entitled “Reduced Hopping Sequences (RHS) for Bluetooth”, filed on Aug. 9, 2000.
TECHNICAL FIELD
This invention relates in general to the field of radio communications and more specifically to a method of reducing the hopping sequence in a frequency hopping system such as Bluetooth.
BACKGROUND
The Bluetooth system operates in the 2.4 Giga-Hertz (GHz) ISM (Industrial Scientific Medical) band. In the United States, the range of the frequency band is 2.400-2.4835 GHz. The Bluetooth system has channel spacing of 1 MHz and uses 79 radio frequency (RF) channels in its standard hopping sequence. The Federal Communications Commission (FCC) rules mandate that any system that operates under FCC regulation 15.247 must hop over at least 75 RF channels, and must use all the frequencies equally (i.e., the devices must spend the same average amount of time at each frequency). Since Bluetooth was designed to operate under FCC regulation 15.247, its hopping pattern is chosen so that approximately equal time is spent in each of the 79 frequencies. Problems with coexistence can arise when other devices share the ISM band with a Bluetooth system, such as IEEE 802.11b wireless local area networks (WLAN) or microwave ovens.
Interferers, which remain stationary in the ISM band, will greatly reduce the throughput of Bluetooth wireless networks and/or increase the packet error rate (PER) whenever the Bluetooth devices hop into the interfered channels. As an example, a Bluetooth connection carrying a voice conversation generally needs a PER of less than 5%. If a microwave oven is operating near the Bluetooth piconet and occupies a bandwidth of 10 MHz with a 50% duty cycle, then on average 5 RF channels will be unusable to the Bluetooth piconet. The PER floor due to interference from the microwave oven will be about 5/79=6%, which will result in poor voice quality. This invention provides a way to reduce the number of hopping channels so that interferers can be avoided in a frequency hopping system like Bluetooth.
BRIEF DESCRIPTION OF THE DRAWINGS
The features of the present invention, which are believed to be novel, are set forth with particularity in the appended claims. The invention, may best be understood by reference to the following description, taken in conjunction with the accompanying drawings, in the several figures of which like reference numerals identify like elements, and in which:
FIG. 1 shows a comparison of a normal hopping sequence and a reduced hopping sequence in accordance with the invention.
FIG. 2 shows a flow chart showing the steps taken in accordance with the invention.
FIG. 3 is a diagram illustrating a Bluetooth system in accordance with the invention.
FIG. 4 is a diagram showing a typical RHS packet that is used to inform the devices in the network of the RHS in accordance with the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
While the specification concludes with claims defining the features of the invention that are regarded as novel, it is believed that the invention will be better understood from a consideration of the following description in conjunction with the drawing figures.
The present invention is a method where the number of hopping frequencies (RF channels) in a frequency hopping system such as Bluetooth is reduced. This allows stationary interferers (in frequency) such as IEEE 802.11b WLAN's or microwave ovens to be avoided so that the throughput and PER of the Bluetooth system can be improved. In the preferred embodiment, the Bluetooth piconet master determines which frequency bands contain a strong interferer. This determination can be made by a probing technique that measures the quality of the RF channels. The quality of the RF channels can be measured using one of a number of channel quality measurements like [E b /(N 0 +I 0 )] where “E b ” stands for bit error, “N” stands for noise and “I” stands for interference, the RSSI (received signal strength indicator) or some other signal quality indicator is measured for each of the RF channels in the standard hopping sequence. In the United States, the standard hopping sequence must have at least 75 channels to be compliant with current FCC regulation 15.247. Alternatively, the master radio can simply monitor the PER on each channel to find which RF channels in the standard hopping sequence have a large PER and should be avoided.
Once the master radio determines the RF channel(s) to avoid, the master can communicate this information to enhanced slave units that are capable of supporting the reduced hopping sequences (RHS) of the present invention. The master device radio can then communicate with the enhanced slaves using RHS, but will continue to communicate with normal Bluetooth slaves using the normal Bluetooth hopping sequence (i.e., using all of the 79 RF channels). The enhanced slave units are those slave units that are programmed in accordance with the present invention to accept a reduction in the number of RF channels used in their hopping sequences.
One way of generating the RHS is illustrated in FIG. 1 . In FIG. 1 , ten frequencies of the normal Bluetooth hopping sequence are designated as f 0 to f 9 . This figure simply illustrates a segment of the hopping sequence to show how the RHS is generated. In this example, let f 4 , f 7 and f 8 be three RF channels (shown in boxes) in the set that need to be avoided due to interference. These RF channels are not used in the RHS, and instead in one example, the previous available RF channel in the sequence is substituted for these avoided frequencies.
In FIG. 1 , the circles illustrate which RF channels are changed in the RHS. Since f 4 is to be avoided, the previous non-interfered with RF channel f 3 is used instead of f 4 in the preferred embodiment. Similarly, f 7 and f 8 are to be avoided, so f 6 , the previous RF channel to f 7 in the standard hopping sequence, is used instead. One advantage of this method of generating the RHS is that all the remaining RF channels are used equally on average. Another advantage is that the difference in the normal hopping sequence and RHS is minimized, which makes it easier for a master radio to support both normal and enhanced Bluetooth slaves. Other methods of forming the RHS can be used such as a modulo operation where the RF channels that are to be avoided (and replaced) are mapped into other RF channel, etc. The system designer can design the appropriate RHS scheme depending on his system needs and the potential interferes the system may encounter.
Systems that use the RHS no longer qualify under FCC regulation 15.247, but they still qualify under FCC regulation 15.249. Under regulation 15.249, devices are permitted to transmit an average power of:
[(0.75 milli-watt)×(number of RF channels used for hopping with 1 MHz bandwidth)].
If the RHS uses 60 RF channels, then the devices can transmit 45 mW or 16.5 dBm. Most current Bluetooth devices are designed to transmit 0 dBm (1 mW), and the cost of the Bluetooth devices will increase when the power output is over a few milli-watts, since an additional power amplifier is typically needed for higher transmission power. Thus, the power restrictions under regulation 15.249 should not be a significant limitation to enhanced Bluetooth devices using the present invention. Furthermore, in many regions outside the United States, power levels in the order of 100 mW (milli-watt) are allowed with much fewer hopping channels (e.g., 20).
There are several ways the master device can choose the reduced hopping sequences. The master can decide individually whether or not to use each of the 79 RF channels by monitoring for interferers in each of the RF channels. The master can then send a packet with 79 information bits which represent the 79 frequencies (RF channels) to indicate whether each one is to be used or not.
Alternatively, the Bluetooth master device can chose whether to use predetermined groups of RF channels. Since IEEE 802.11b devices, which are one of the potential interferers, typically use one of three 22 MHz bands, the master device can group its RF channels according to the 802.11b frequency plan. If it is determined by the master unit that an 802.11b network is using one or more of these bands, the master can indicate to the enhanced slaves in the system not to use the affected frequency groups. A frequency group for the microwave oven band can also be used. Using predetermined groupings will decrease the amount of information that the master needs to communicate to the enhanced slaves on which RF channels to avoid. In this case, the information transmitted to the enhanced slaves does not require 79 bits and can be transmitted using much less bits of information. The predetermined RF channel groupings can be preprogrammed into the master and slave units, and in that way, less information needs to be transmitted by the master in order to let the slave units know which RF channels will be used.
In FIG. 2 , there is shown a flowchart highlighting some of the steps taken in accordance with the invention. In step 202 , the master unit determines, using one of the previously discussed techniques, if interference is present in any of the Bluetooth RF channels. If it is determined that interference is present, in step 204 the master unit sends a message to the slave units programmed to accept the RHS scheme (referred to as enhanced slave units). The message allows the slave units to determine the reduced hopping sequence that will be used and what channels will be omitted from the sequence. Depending on the particular design, the message may also provide information as to what RF channels (e.g., previous non-interfered with channel) will replace, if any, the omitted channels, bandwidth of each of the channels, etc. As mentioned previously, other channels beside the previous channel to an interfered with channel can replace the omitted channels.
A sample RHS message for use in step 204 is shown in FIG. 4 . The message 400 includes a header 402 and a section 404 that includes 79 bits corresponding to each of the RF channels available in the Bluetooth system. In one illustrative example, a “1” in a corresponding bit in section 404 informs the receiving radio(s) that a particular RF channel is in the RHS. A “0” in one of the bits means that channel is excluded from the RHS. In the preferred embodiment, the receiving radio would also know to use the channel preceding the excluded channel as previously discussed in association with FIG. 1 . This information as to what channel to use for the excluded channel(s) can be preprogrammed into all the communication units in the system, or can be sent in other packets by the unit transmitting the RHS message. Finally, in step 206 the master and slave units communicate with each other using the RHS, thereby avoiding the potential interference that had been detected by the master unit.
In FIG. 3 , there is shown a frequency hopping system 300 such as a Bluetooth system in accordance with the invention. The system comprises a master unit 302 and one or more slave units 304 , 306 . A potential interferer such as a microwave oven or WLAN 308 is shown in RF proximity to the Bluetooth system.
Although the above discussion has focused on the Bluetooth master as the device in the Bluetooth system that monitors for interferers, and transmits messages to the slave units, in an alternate embodiment, one or more of the slave units in the system could be assigned to perform these tasks. In another embodiment, the device or devices in charge of deciding the RHS can also control the bandwidth of the hopping channels, for example, they could make one of the channels in the RHS a 4 MHz channel instead of the standard 1 MHz, if conditions warrant it.
In still another embodiment of the invention, one of the communication units in the Bluetooth piconet such as the piconet master, could be a dual mode device which is capable of operating in both WLAN (or other potential type of interfering system to the Bluetooth system) and Bluetooth networks. In such a situation, the communication device can use its knowledge of both of the systems to allocate some of the RF channels to the WLAN activity (first system) and use some or all of the other available RF channels for the RHS for use in the Bluetooth system (second system). This allocation by one communication device common to both systems can help minimize interference between the two systems.
While the preferred embodiments of the invention have been illustrated and described, it will be clear that the invention is not so limited. Numerous modifications, changes, variations, substitutions and equivalents will occur to those skilled in the art without departing from the spirit and scope of the present invention as defined by the appended claims. For example, similar methods can also be used to reduce the number of RF channels used in other systems and under other regulations. | A frequency hopping system such as a Bluetooth system ( 300 ) can reduce the number of RF channels it hops during a normal hopping sequence cycle providing for a Reduced Hopping Sequence (RHS). A communication unit operating in the system such as the Bluetooth master unit ( 302 ) determines if any of the RF channels has interference. If any of the channels has interference, the Bluetooth master sends a message to one or more slave units ( 304, 306 ) informing them of which channels will be removed from the hopping sequence due to potential interference problems. The units will then use the new RHS for their transmissions, thus avoiding the interference problems (e.g., both avoiding interference in the system's receivers and avoiding creating interference on frequencies that are already occupied by other neighboring systems). | 7 |
RELATED APPLICATIONS
[0001] This application is a continuation in part of U.S. patent application Ser. No. 09/295,907, filed Apr. 21, 1999, which is a divisional of U.S. patent application Ser. No. 09/169,449, filed Oct. 9, 1998, now U.S. Pat. No. 6,133,440, which claims the benefit of U.S. Provisional Patent Application Serial No. 60/061,681, filed Oct. 10, 1997 and U.S. Provisional Patent Application Serial No. 60/098,271, filed Aug. 28, 1998, each of which is entitled “Process for Preparation of Immunomodulatory Carbohydrates from Aloe.”
FIELD OF THE INVENTION
[0002] The present application relates to methods for activating and purifying polysaccharides from Aloe. In particular, the invention relates to methods for isolating polysaccharides with immunomodulatory activity from Aloe. The present invention includes the activated mixture of polysaccharides (referred to herein as “Immuno-10”or “Immuno-10 polysaccharide”), produced by the methods of the invention. The invention also includes the use of the polysaccharides as immunostimulating, immunomodulating and wound healing agents.
BACKGROUND OF THE INVENTION
[0003] Aloe is an intricate plant which contains many biologically active substances. (Cohen et al. in Wound Healing/Biochemical and Clinical Aspects, 1st ed. W B Saunders, Philadelphia (1992)). Over 300 species of Aloe are known, most of which are indigenous to Africa. Studies have shown that the biologically active substances are located in three separate sections of the aloe leaf—a clear gel fillet located in the center of the leaf, in the leaf rind or cortex of the leaf and in a yellow fluid contained in the pericyclic cells of the vascular bundles, located between the leaf rind and the internal gel fillet, referred to as the latex. Historically, Aloe products have been used in dermatological applications for the treatment of burns, sores and other wounds. These uses have stimulated a great deal of research on identifying compounds from Aloe that have clinical efficacy, particularly anti-inflammatory activity. (See, e.g., Grindlay and Reynolds (1986) J. of Ethnopharmacology 16:117-151; Hart et al. (1988) J. of Ethnopharmacology 23:61-71). As a result of these studies there have been numerous reports of Aloe compounds having diverse biological activities, including anti-tumor activity, anti-acid activity (Hirata and Suga (1977) Z. Naturforsch 32c:731-734), anti-diabetic activity, tyrosinase inhibiting activity (Yagi et al. (1987) Planta medica 515-517) and antioxidant activity (International Application Serial No. PCT/US95/07404, published Dec. 19, 1996, publication number WO 96/40182).
[0004] It has also been reported that Aloe products can stimulate the immune system. The ability of Aloe to stimulate the immune system has been attributed to polysaccharides present in the gel. (See, e.g., Day et al. (1922) J. Am. Pharm. Assoc. 11:462-463; Flagg (1959) American Perfumes and Aromatics 74:27-28, 61; Waller et al. (1978) Proc. Okla. Acad. Sci. 58:69-76; Shcherbukhin et al. (1979) Applied Biochemistry & Microbiology 15:892-896; Mandal et al. (1980) Carbohydrate Research 86:247-257; Mandal et al. (1980) Carbohydrate Research 87:249-256; Winters et al. (1981) Eco. Botany 35:89-95; Robson et al. (1982) J. Burn Care Rehab. 3:157-163; Ivan et al. (1983) Drug & Cosmetic Ind. 52-54, 105-106; Smothers (1983) Drug & Cosmetic Ind. 40:77-80; Mandal et al. (1983) Indian J. of Chem. 22B:890-893; Vilkas et al. (1986) Biochimie 68:1123-1127; Waller et al. (1994) Cosmetic Toiletries Manufacturing Worldwide 64-80; U.S. Pat. No. 5,308,838 of McAnalley et al.).
[0005] Aloe products are also used extensively in the cosmetic industry to protect skin against the harmful effects of ultraviolet radiation. (Grollier et al. U.S. Pat. No. 4,656,029, issued Apr. 7, 1987). Chronic exposure of the skin to ultraviolet radiation causes skin cancer in humans and laboratory animals. Exposure of the skin of laboratory animals to ultraviolet B (UVB) radiation (280-320 nm) causes suppression of the skins immune system, which impairs its ability to develop an immune response to UV-induced skin cancers, contact-sensitizing haptens and a variety of infectious microorganism. (See, Strickland (1994) J. Invest. Dermatol. 102:197-204, and references cited therein). Studies by Strickland et al. show that topical application of Aloe vera gel reduces the suppression of the immune system caused by UVB exposure. (Strickland (1994) J. Invest. Dermatol. 102:197-204).
[0006] The ability of native gel to reduce suppression of the immune system, is very low and irregular and also decreases with time. One hypothesis is that the UV-B protective factor is hydrolyzed by naturally occurring enzymes in the Aloe plant and/or by bacterial degradation. Therefore, it would seem likely that isolating polysaccharides from Aloe would help preserve this immunomodulatory activity. Previous prior art methods for the bulk isolation of polysaccharides from Aloe, however, do not effectively preserve the immunomodulatory activity. These methods, described for example in U.S. Pat. application Nos. 4,957,907, 4,966,892 and 5,356,811, use lengthy (4-24 hours) alcohol precipitation and centrifugation steps. Given the failure of the prior art methods to effectively preserve the immunomodulatory activity of Aloe gel, it would be useful to have a procedure for the isolation of polysaccharides from Aloe that would allow the immunomodulatory activity to be retained and stabilized. The present invention provides such methods.
SUMMARY OF THE INVENTION
[0007] The present application relates to methods for activating and isolating a mixture of polysaccharides from Aloe. Included in the present invention is the activated mixture of polysaccharides produced and the use of said mixture as an immunostimulating, immunomodulating and wound healing agent. The activity of polysaccharides isolated by the method of this invention is much higher and much more stable and reproducible than that of native Aloe gel extracts.
[0008] The method of the present invention is comprised of (a) extracting Aloe gel juice from Aloe; (b) performing a controlled limited enzymatic hydrolysis of the total polysaccharides in said Aloe gel juice at a temperature and for a period of time suitable for limited carbohydrate hydrolysis; (c) terminating said hydrolysis; and (d) optionally decolorizing and filtering said hydrolyzed product. In a preferred embodiment the limited hydrolysis is performed by the addition of cellulase at 25° C.±1° C. for a period of 2-2.5 hours using a ratio of 0.5 g -2.5 g of cellulase to 216 L of gel extract. A schematic diagram of the instant method is provided in FIG. 1. In another embodiment of the instant invention, the method further comprises the step of (e) purifying the hydrolyzed product by nanofiltration. The nanofiltration may be repeated as many times as necessary to obtain the desired purity.
[0009] The present invention includes the mixture of polysaccharides (referred to herein as “Immuno-10 ”or “Immuno-10 polysaccharide”) prepared and isolated by the methods of this invention. Said composition of matter is characterized in detail below.
[0010] The present invention also includes the use of Immuno-10 as an immunostimulating, immunomodulating and wound healing agent. Immuno-10 prevents suppression of contact hypersensitivity (CH) in mice exposed to UVB radiation and also inhibits UVB irradiation-induced tumor necrosis factor (TNF-α) release in human epidermoid carcinoma cell line. The Immuno-10 isolated by the method of this invention can be used in an oral or topical formulation for the restoration or stimulation of the human immune system, for individuals suffering immunodeficiency or immune-suppressing diseases or for therapeutic treatment for diseases, such as HIV. The Immuno-10 isolated by the method of this invention is also useful for wound healing. The polysaccharides isolated by the method of this invention are more active and more stable than native Aloe gel.
[0011] The methods described herein include a limited and controlled hydrolysis of Aloe polysaccharides, which operates to increase the stability and immunomodulatory activity of Aloe polysaccharides. The method is faster, simpler and more amenable to scale-up than prior art methods, and does not involve the use of organic solvents. Moreover, the processes described herein increase the solubility of Aloe polysaccharide and reduce the viscosity of solutions thereof without loss of the immunomodulatory activity. Immuno-10 isolated using the method of this invention shows qualitatively-similar UVB protective activity as the activated bulk polysaccharide purified from the same Aloe gel extracts, but has a higher specific activity than the bulk polysaccharide. Additionally, the purified Immuno-10 exhibits UVB CH restorative activity that is at least twice as high as that of native Aloe gel.
[0012] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention as claimed.
BRIEF DESCRIPTION OF THE FIGURES
[0013] [0013]FIG. 1 illustrates schematically the general method of the present invention for the preparation of Immuno-10 from Aloe.
[0014] [0014]FIG. 2 depicts a chromatogram of Immuno-10, following limited enzyme hydrolysis, decolorization and filtration (Example 1). The chromatography was performed on a on a Sepharose CL-4B column, monitoring absorbance at 490 nm using the phenol sulfuric acid method.
[0015] [0015]FIG. 3 depicts the chromatogram of partially purified Immuno-10 prepared according to the method of Example 3. The chromatography was performed on a Sephadex G-100 column and absorbance at 490 nm was monitored.
[0016] [0016]FIG. 4 illustrates the degradation of Aloe polysaccharides by cellulase at 3 minutes (⋄), 10 minutes (◯), 30 minutes (Δ), 60 minutes (♦), 120 minutes (▴), 24 hours () and 48 hours (▪).
[0017] [0017]FIG. 5 depicts a chromatogram of Aloe polysaccharide isolated by three different methods: polysaccharide purified from fresh extract using known methods (▴), polysaccharide derived from freeze dried Aloe gel (▪) and polysaccharide derived from Aloe whole leaf (). The chromatography was performed on a Sepharose CL-4B column, monitoring absorbance at 490 nm.
[0018] [0018]FIG. 6 depicts a chromatogram of Immuno-10 on a Sephadex G-100 column after standing three months in H 2 O at pH 4.3 (◯) and pH 7.8 () at room temperature.
[0019] [0019]FIG. 7 depicts the chromatogram of purified native Aloe polysaccharide on a Sephadex G-100 column after standing three months in H 2 O at pH 4.3 (◯) and pH 7.8 () at room temperature.
[0020] [0020]FIG. 8 illustrates graphically the ability of Immuno 10 to restore skin immune function (contact hypersensitivity UVB assay).
[0021] [0021]FIG. 9 illustrates graphically the inhibition of UVB irradiation-induced tumor necrosis factor-α (TNF-α) release by Immuno-10.
[0022] [0022]FIG. 10 illustrates graphically the stimulation of TNF-α release from mouse peritoneal macrophages by Immuno-10.
[0023] [0023]FIG. 11 illustrates graphically the stimulation of cell proliferation by Immuno-10.
DETAILED DESCRIPTION OF THE INVENTION
[0024] The present application is drawn to methods for activating and isolating a defined biologically active mixture of polysaccharides from Aloe. The term “Aloe” refers to the genus of plants found worldwide from the Liliaceae family of which the Aloe barbadensis plant is a species. In one embodiment the method of the present invention is comprised of (a) extracting Aloe gel juice from Aloe; (b) performing a limited and controlled hydrolysis of the total polysaccharides in said Aloe gel juice at a temperature and for a period of time suitable for limited carbohydrate hydrolysis; (c) terminating said hydrolysis; and (d) optionally decolorizing and filtering said hydrolyzed product.
[0025] In a second embodiment the method of the present is comprised of (a) extracting Aloe gel juice from Aloe; (b) performing a limited and controlled hydrolysis of the total polysaccharides in said Aloe gel juice at a temperature and for a period of time suitable for limited carbohydrate hydrolysis; (c) terminating said hydrolysis to provide a hydrolyzed product; (d) optionally decolorizing and filtering said hydrolyzed product and (e) purifying the hydrolyzed product by nanofiltration. The nanofiltration may be repeated as many times as necessary to provide the purity desired.
[0026] A schematic diagram of the first embodiment of the instant method is provided in FIG. 1. With reference to FIG. 1, Aloe gel juice (AGJ) is produced from fresh gel fillets by any method known in the art, including but not limited to grinding, using a “Thompson Aloe Juice Extractor” (Thompson Manufacturing Co., Harlingen, Tex.) or using pressure rollers. The AGJ is then mixed with a hydrolyzing agent. Examples of hydrolyzing agents include but are not limited to enzymes, such as cellulase, pectinase or mannanase and non-enzymatic hydrolyzing agents, such as hydrochloric acid and trifluoroacetic acid. In a preferred embodiment the hydrolyzing agent is an enzyme. Most preferably the hydrolyzing agent is a cellulase, such as cellulase 4000 (Valley Research Inc.). The resulting mixture is allowed to incubate at a temperature and for a length of time suitable for limited carbohydrate hydrolysis (see Example 1). For example when the hydrolyzing agent is cellulase this is preferably 2-2.5 hours at 25° C.±1° C. using a ratio of 0.5 g to 2.5 g of cellulase to 216 L of gel extract (see Example 5).
[0027] Carbohydrate hydrolysis is then stopped after the appropriate period of time. If a cellulase is used, this is accomplished preferably by heating the digestion mixture to a high temperature. The resulting Immuno-10 has a red color at this stage, and this color may optionally be removed by mixing the Immuno-10 with charcoal particles to form a slurry (see Example 1) or by column chromatography. Examples of suitable chromatography resins, including but not limited to reverse-phase resins. Examples of reverse phase resins, include but are not limited to aromatic resins, such as the XAD series of resins and CG-161 and non-aromatic resins, such as C-4, C-8 and C-18. In preferred embodiments, such Immuno-10 slurry is filtered in order to remove the charcoal particles. This can be accomplished by any of the methods known in the art. Preferred embodiments of the invention use a multistep filtration scheme, in which the slurry is passed through a series of filters of progressively smaller pore sizes (see Example 1 and Tables 1 and 2). For example, in some embodiments, the slurry is filtered over 30 μm filter paper, then over 1.0 μm filter paper, and finally over 0.7 μm filter paper. In some embodiments, a filtration aid, such as a celite, FW12 or Fw14 is included in the mixture to be filtered. Following filtration using this method, the filtrate is decolorized and free of fine charcoal particles.
[0028] Following the optional decolorization and filtration, the Immuno-10 may be dried for storage by lyophilization or spray-drying. Typical yields using the instant method are approximately 6 g of lyophilized solids per liter of AGJ. Chromatography of Immuno-10 on a Sepharose CL-4B column reveals that it contains both polysaccharide and monosaccharide fractions as evidenced by the presence of two carbohydrate peaks at 490 nm (FIG. 2). Although the immune regulating activity is contained within the polysaccharide peak, the monosaccharides do not affect this activity (data not shown). The monosaccharides can be removed by diafiltration/dialysis of AGJ prior to the limited enzymatic digestion.
[0029] Examples 2 and 3 describe methods for the preparation of pharmaceutical grade Immuno-10, which is a purer form of Immuno-10 having greater biological activity and stability.
[0030] Example 4 describes a method for the purification of Immuno-10 using nanofiltration. In the two examples described in Example 4, the nanofiltration is performed twice, however this step may be repeated as many times as necessary to obtain the desired purity of Immuno-10. Nanofiltration is well suited for large scale synthesis of Immuno-10.
[0031] Included in the present invention is the activated polysaccharide (referred to herein as “Immuno-10”or “Immuno-10 polysaccharide”), produced by the methods of the invention.
[0032] The composition and chemical structure of the activated polysaccharides in Immuno-10 was determined using pharmaceutical grade Immuno-10 having a purity of >95% and is as follows:
[0033] Size exclusion chromatography analysis shows that the average molecular weight of the polysaccharides in Immuno-10 is 70˜80 kDa with a range between 50˜200 kDa. The molecular weight was determined using size exclusion chromatography on a Sephadex G-100 column and HPLC gel permeation on a Superose 12 column (H10/30 Pharmacia).
[0034] Analysis of the monosaccharide composition indicates that the polysaccharides in Immuno-10 contain D-galactose (approx 5% or less), D-glucose (approx. 5% or less) and D-mannose (approximately 90%). The polysaccharides in Immuno-10 may also contain trace amounts of xylose and arabinose.
[0035] Pharmaceutical grade Immuno-10, which is more highly purified (see Examples 2 and 3), contains mainly D-galactose and D-mannose in a ratio of 1 to 9.6±2.2.
[0036] Proton and 13 C NMR-spectroscopy analysis indicates that the monosaccharide linkages are primarily β-1,4 linkages. The proton and 13 C-NMR spectra were analyzed on a Varian XL-300 spectrometer. The main structure of Immuno-10 polysaccharide is β-1,4 glucomannan. Furthermore, the polysaccharide is highly acetylated (approximately 1 acetyl group per sugar residue on average). The 2, 3 and 6 positions of the monosaccharide units can be independently substituted with an —OH or an —OAc.
[0037] Chromatography of Immuno-10 reveals that it contains both polysaccharide and monosaccharide fractions (see FIG. 2). The monosaccharide composition of the activated polysaccharide was determined by high performance anion-exchange chromatography on a Dionex CarboPac PA1 column with pulsed amperometric detection (HPAEC-PAD) using a Dionex Bio-Lc system. Although the immune regulating activity is contained within the polysaccharide peak, the monosaccharides do not affect this activity (data not shown). Immuno-10 may also contain various salts which also do not affect its activity.
[0038] Immuno-10 is stable to heat and protease treatments without losing its biological activity, which further indicates that the biological activity of Immuno-10 can be attributed to the activated polysaccharide.
[0039] The Immuno-10 isolated by the method of this invention has greater stability than Aloe polysaccharides isolated using previously known methods. Examples 6 and 7 (FIGS. 5 - 8 ) illustrate the relationship between the method of processing the polysaccharide and its stability.
[0040] This invention also includes the use of Immuno-10 as an immunostimulating, immunomodulating and wound healing agent.
[0041] Immunomodulating activity. Immuno-10 restores the UVB-suppressed immune response (contact hypersensitivity); and inhibits UVB-induced Tumor Necrosis Factor α (TNF-α) release from keratinocytes (Human epidermoid carcinoma cells, KB cells).
[0042] The local suppression model was used to determine the ability of Immuno-10 to reverse the UVB-suppressed skin immune function, referred to herein as the restorative activity of Immuno-10, as set forth schematically in Example 8. (See, Strickland (1994) J. Invest. Dermatol. 102:197-204 and Vincek et al. (1994) Cancer Research 53:728, which are incorporated herein by reference). In the local suppression model, C3H/HeN mice are exposed to low doses of UVB radiation, which inhibits the induction of the contact hypersensitivity (CH) response to haptens applied at the site of the irradiation. Briefly, the abdominal fur of the mice was shaved and exposed to UVB irradiation at 2000 J/m 2 , after which Immuno-10 (0.25 mg/mL) in Aquaphor, a known vehicle, was applied to the irradiated area. Three days later the mice were sensitized on the site of irradiation by application of 2,4-dinitrobenzene (DNFB) (0.3%, 50 μL). Six days later the thickness of their ears was measured and then the mice were challenged by application of DNFB (0.2%, 5 μL) to both sides of their ears. Twenty-four hours later the thickness of their ears was measured again. The results are set forth in FIG. 8.
[0043] In most of the experiments performed, UVB exposure inhibited the CH response by 80˜100%. With reference to FIG. 8, this group was used as the negative (suppressed) control (0% CH response). The positive control group of mice received no UVB irradiation and no treatment with Immuno-10 (vehicle only), but were sensitized and challenged (100% CH response). The vehicle (blank) control group of mice received no UVB irradiation, no treatment with Immuno-10 (vehicle only) and no sensitization, but were challenged. This group was used to subtract the net ear swelling caused by any challenge chemical irritation. The Immuno-10 treated groups of mice were treated in the same way as the suppressed control, except that the mice were treated with Immuno-10 in vehicle instead of vehicle only. The percentage of recovery by Immuno-10 was calculated using the following equation:
% Recovery = ( A - B ) ( C - B ) × 100
[0044] wherein
[0045] A=Net ear swelling of Immuno-10 treated group—Net ear swelling of Blank group;
[0046] B=Net ear swelling of the Suppressed group—Net ear swelling of the Blank group; and
[0047] C=Net ear swelling of the Positive group—Net ear swelling of the Blank group.
[0048] The higher the percentage of recovery, the more active the Immuno-10. As can be seen in FIG. 8, the activity of Immuno-10 is between 30˜80% with an average of about 60%. The immunomodulating activity was stable when Immuno-10 was stored in a solution at 4° C. for 3 months or in a solid form at room temperature for one year.
[0049] It has been reported that UVB-induced TNF-α release is involved in the mediation of local immune suppression within the epidermis. An in vitro model was developed to determine the suppression of UVB-induced TNF-α release by Immuno-10. This method is described in Example 9. Human epidermoid carcinoma cell line (KB cells) were used (normal cells do not produce enough TNF-α to be measurable by ELISA). The results are set forth in FIG. 9. The X-axis in FIG. 9 represents the dose of Immuno-10 (mg/mL final concentration in cell media). The Y-axis shows the percentage of inhibition by Immuno-10. The percentage of inhibition by Immuno-10 was calculated using the following formula:
% Inhibition = 1 - ( A - B ) ( C - B ) × 100
[0050] A=TNF-α amount in the media from the UVB—irradiated and Immuno-10 treated cells;
[0051] B=TNF-α amount in the media from the cells without UVB—irradiation; and
[0052] C=TNF-α amount in the media from the UVB—irradiated cells, but without Immuno-10 treatment.
[0053] As can be seen in FIG. 9, Immuno-10 showed a dose-dependent inhibition of UVB-induced TNF-α release from KB cells. At the concentration of 1 mg/mL, Immuno-10 inhibited the release by almost 100%.
[0054] Immunostimulating activity. Immuno-10 activates macrophages by stimulating TNF-α release.
[0055] Host defense against malignant tumors consists of several different mechanisms and impairment or failure of immunological defense may lead to the development or progression of malignant disease. Macrophages are antigen-processing cells and have been demonstrated to be both cytotoxic and phagocytic. Each of these functions are significantly enhanced when macrophages are activated. Selective stimulation of this cell population could be important in contributing to the development of therapeutic applications. Activated macrophages are also crucial in the body's ability to heal wounds. Tumor Necrosis Factor α (TNF-α ), one of the cytokines released by macrophages, plays a critical role in mediating the signal transduction of the defense system. Example 10 describes the method used to determine Immuno-10 stimulated macrophage activation. The results are set forth in FIG. 10. As shown in FIG. 10, a dose-dependent stimulation of TNF-α release from mouse peritoneal macrophages by Immuno-10 was detected. At the concentration of 0.5 μg Immuno-10 per mL, Immuno-10-stimulated macrophages released 500 times more TNF-α than the unstimulated cells. As can also be seen in FIG. 10, under the same experimental conditions, native Aloe gel did not induce TNF-α release from macrophages. This result indicates that Immuno-10 can be used as both a non-specific stimulator of the immune system and for wound healing.
[0056] Wound healing activity. Immuno-10 stimulates fibroblast proliferation (baby hamster kidney cells, BHK-21 cells).
[0057] Example 11 describes the method used to determine Immuno-10 cell proliferation. The MTT method was used to determine the stimulated cell proliferation. The results are set forth in FIG. 11. As can be seen in FIG. 11, Immuno-10 stimulates BHK-21 cell growth in a dose-dependent manner.
[0058] The following examples are provided for illustrative purposes only and are not intended to limit the scope of the invention.
EXAMPLES
Example 1
Isolation and Purification of Immuno-10
[0059] Immuno-10 was isolated and purified as outlined in FIG. 1. Briefly, fresh Aloe barbadensis gel extract was subjected to limited enzyme digestion at a temperature and for a length of time suitable for limited carbohydrate hydrolysis. This is typically 2 hours at 25° C., using cellulase as the enzyme. The activated Aloe gel was partially purified using activated carbon and filtration (I-10). The activated polysaccharide was then further purified by dialysis, ethanol precipitation and size exclusion chromatography.
[0060] Limited Enzyme Digestion
[0061] Aloe Gel Juice (AGJ) (10 L) produced from fresh gel fillets (provided by Aloecorp (Harlingen, Tex.)) was heated to 25° C. with a heat exchanger consisting of 60° C. water circulating through a ¼″316 stainless steel coil while gently mixing with a mechanical agitator equipped with a marine propeller blade (A100). A solution of 116 mg of cellulase 4000 (Valley Research Inc.) in 10 mL of 50 mM aqueous citrate at pH=6 was added and the mixture was gently stirred for 2 hours.
[0062] Enzyme Deactivation
[0063] After two hours, the reaction mixture was heated to about 90° C. for a minimum of 30 minutes. The reaction mixture was then immersed in an ice-water bath to cool the material to room temperature.
[0064] Decolorization and Filtration
[0065] Charcoal was used to remove the red color developed during the enzyme deactivation. The material was divided into two 5.0 L batches. To each of the 5.0 L batches, 100.0 g of coarse charcoal (Darco 20×40, purchased from Norit) was added and the mixture gently stirred for one hour at room temperature. Subsequently, 50.0 g of celite 545 (Aldrich Chemical Co.) was added and the slurry stirred for an additional 10 minutes.
[0066] The slurry was then pumped into a pressure filter equipped with a 30 μm filter paper (Whatman Grade 113) to remove the solids. The filtrate contained a small amount of fine charcoal particles that channeled through the filter. The material was clarified when filtered over two superimposed filters, a 1.0 μm pore size filter paper (Whatman #1) on top of 0.7 μm filter paper (Whatman GF/F) that were coated with 100 g of celite 545. The filtrate was decolorized and free of fine charcoal particles. The activated polysaccharide was further purified by dialysis, ethanol precipitation and size exclusion chromatography. The filtration data is summarized forth in Tables 1 and 2.
TABLE 1 First Filtration Parameter Value Volume of Slurry 5 L Filter paper Whatman #113 Pore Size 30 μm Filter Aid None Filtration Area 113 cm 2 Maximum Pressure <1 psi Average Filtration Rate 7.0 mL/min/cm 2 Liquid Recovery Quantitative Material Appearance Contained fine charcoal Particles
[0067] [0067] TABLE 2 Second Filtration Parameter Value Volume of Slurry 5 L Filter paper Whatman #1 on top of Whatman GF/F (combination) Pore Size 1.0 μm on top of 0.7 μm Filter Aid 100 g of Celite 545 Filtration Area 113 cm 2 Maximum Pressure 2 psi Average Filtration Rate 0.74 mL/min/cm 2 Liquid Recovery Quantitative Material Appearance Clear
[0068] Lyophilization
[0069] Following filtration the two batches were combined and the material was transferred into lyophilization trays, frozen and lyophilized in a 20 L VirTis Freeze Dryer, to yield 57.14 g of Immuno-10, which is equivalent to 5.71 g of Immuno-10 per liter of AGJ.
Example 2
Preparation of Pharmaceutical Grade Immuno-10 Using a Hollow-Fiber Cartridge
[0070] Ten grams of freeze-dried Aloe gel was dissolved in 1.8 L of distilled water in a 2 L beaker. The slurry was stirred overnight at 4° C. producing a homogenous mixture. The mixture was filtered through filter paper (Whatman #3) to remove any particulates and the volume of the filtrate was adjusted to 2 L. The mixture was brought to room temperature and a solution of 4.63 mg of cellulase 4000 (Valley Research Inc.) in 5 mL of 50 mM aqueous citrate at pH 6 was added. The filtrate was then pumped through a Hollow-fiber cartridge (UFP-5-E-6, molecular weight cutoff: 5000 Da, A/G Technology Corporation) at an inlet pressure between 10 to 15 psi. Permeate, which had a molecular weight of less than 5,000 Da, was collected in a separate 2 L beaker. The concentrate, which had a molecular weight of greater than 5,000 Da, was collected in the same beaker as the starting filtrate. This mixture was continuously stirred and when the volume of starting filtrate was reduced to one liter, distilled water (1L) was added to bring the volume back to 2 L. This procedure was repeated 5 times. A total of three 2 L fractions of permeate were collected. The final concentrate was collected as the retained fraction. It took an average of approximately 2.5 hours to collect each 2 L permeate fraction. The fractions were transferred into lyophilization traps, frozen and lyophilized in a 20 L VirTis Freeze Dryer. The yields of the permeate fractions I, II and III, and the retained fraction were 4.88 g, 1.77 g, 0.56 g and 0.37 g, respectively. The retained fraction had the highest activity to restore UVB-suppressed contact hypersensitivity. Fraction III of the permeates had moderate activity to restore UVB-suppressed contact hypersensitivity. Fractions I and II of the permeates were inactive.
Example 3
Process for Preparation of Pharmaceutical Grade Immuno-10
[0071] Immuno-10 (50 g), prepared by the method described in Example 1, was dissolved in distilled water (diH 2 O) to a final volume of 200 mL. Ethanol (66.7 mL, 25% final concentration) was then added to this solution. The addition of ethanol was done slowly while stirring. The solution was then stirred for an additional 30 minutes, during which time a precipitate formed. The mixture was centrifuged at 2500 rpm for 10 minutes (Jouan CR412), and the precipitate was washed once with 25% ethanol, centrifuged and resolublized in diH 2 O. The resulting solution was lyophilized to dryness (ppt/25%). An additional 133.3 mL of ethanol (25%˜50%) was added to the supernatant, as described above, the solution was again stirred for 30 minutes, and the precipitate was collected, washed with 50% ethanol and lyophilized (ppt/25%-50%). This procedure was repeated two more times recrystallizing with 50-75% ethanol (ppt/50%-75%) and 75-80% ethanol (ppt/75%-80%). The solid recoveries of the precipitate for ppt/25%, ppt/25-50%, ppt/50-75% and ppt/75-80% were 0.3%, 20.5%, 10.3% and 1.5%, respectively. The product of ppt/50-75% was further fractionated on a Sephadex G-100 column (2.5×68 cm). The fractions of the polysaccharide peak (left peak, FIG. 3) were combined and lyophilized, to produce pharmaceutical grade Immuno-10. The recovery of the pharmaceutical grade Immuno-10 from the ppt/50-75% was 15.8%.
Example 4
Purification of Immuno-10 Using Nanofiltration
[0072] Immuno-10 (1132 L of a gel containing 219.6 kg of solid) was prepared by the method described in Example 1, through the step of decolorization/filtration and excluding the step of lyophilization. The gel (1132 L) was diluted with water to 4044 L and concentrated down to 1199 L using 10 kD filters (4×90 sq. ft) over 4.25 hours. The retentate was then diluted with 2600 L of water and concentrated down to 950 L using 10 kD filters over 5.33 hours. This solution was then spray dried to obtain 42 kg of the purified product.
[0073] In a second experiment, Immuno-10 gel (1140 L), prepared by the method described in Example 1, through the step of decolorization/filtration, was diluted to 6000 L and concentrated down to 1200 L using 10 kD filters over 7.5 hours. The retentate was then diluted with 1287 L of water and concentration was continued to 1200 L over 2.5 hours. The solution was then spray dried to yielded 38.26 kg of the purified product.
Example 5
Time Dependant Degradation of Aloe Vera Gel (AJG) Polysaccharide
[0074] Fresh Aloe vera gel extract was treated with cellulase (11.57 mg cellulase per liter of gel extract) at room temperature for 3 minutes, 10 minutes, 30 minutes, 60 minutes, 120 minutes, 24 hours and 48 hours. At the end of the treatment, the gel extracts were heated at 95° C. in a water bath for 30 minutes followed by centrifugation at 2500 rpm for 10 minutes. The supernatants were lyophilized to dryness. The molecular weight distribution of polysaccharides in the treated gel extracts was analyzed by size exclusion chromatography on a Sephadex G-75 column (2.5×68 cm, 177-179 mg of sample was applied to the column). Polysaccharides having a molecular weight ≧75,000 Da eluted at the void volume, while monosaccharides and some oligosaccharides eluted at the column volume (see FIG. 4). The preferred hydrolysis reaction time, based upon biological activity of the resultant product, was determined to be 120 minutes. As can be seen in FIG. 4, treatment with cellulase for 120 minutes resulted in a sharp polysaccharide peak having no shoulder (▴). Treatment with cellulase for 24 hours () or 48 hours (▪), resulted in a significant decrease in the absorbance of the polysaccharide peak, while the absorbance of the monosaccharide and oligosaccharide peak was increased. The product obtained by treatment for 3 minutes (⋄), 10 minutes (◯) and 30 minutes (Δ) resulted in a polysaccharide peak having a shoulder.
Example 6
Stability of Aloe Polysaccharide in Different Aloe Preparations
[0075] The stability of polysaccharide in fresh Aloe gel extract (purified using standard methods of purification, i.e., dialysis and ethanol precipitation), freeze-dried Aloe gel and freeze-dried Aloe whole leaf was studied by size exclusion chromatography on Sepharose CL-4B column (see FIG. 5). As can be seen in FIG. 5, the Aloe polysaccharide isolated from the fresh Aloe gel extract has a molecular weight of ˜2 million Da. The polysaccharide in the freeze-dried Aloe whole leaf has a lower molecular weight than that of the polysaccharide isolated from the fresh Aloe gel extract and the polysaccharide in the freeze-dried Aloe gel has a molecular weight of ˜500,000 Da. This result demonstrates the relationship between the method of processing the polysaccharide and the stability of the Aloe polysaccharide.
Example 7
Stability of Immuno-10 Polysaccharide
[0076] Immuno-b 10 contains some salts and other small molecules besides polysaccharide. The pH of Immuno-10 in distilled water (diH 2 O) is about 4.3. To study the stability of Immuno-10 polysaccharide, both purified native Aloe polysaccharide and solutions of Immuno-10 at pH 4.3 or pH 7.8 were left at room temperature for three months. Sodium azide at a final concentration of 0.02% was added to the Immuno-10 or polysaccharide solutions to inhibit microbial growth. The degradation of polysaccharide in these samples was analyzed on Sephadex G-100 column. FIG. 6 depicts the chromatogram showing that the polysaccharide absorbance of Immuno-10 at 490 nm was very similar at both pH 4.3 and pH 7.8. Although the polysaccharide peak shifted slightly to the right side at pH 4.3, it was still very stable under both pH conditions compared with the starting material. Under the same condition, the purified native polysaccharide was partially degraded at pH 7.8 (FIG. 7). The slight shift of the polysaccharide peak could be due to repacking of the Sephadex G-100 column.
Example 8
Determination of Immuno-10 Restored UVB-Suppressed Contact Hypersensitivity
[0077] Specific-pathogen-free female C3H/HeN mice were obtained from Harlan Sprague Dawley and maintained in a pathogen-free facility in accordance with National Research Council of Laboratory Animal Care guidelines. Each experiment was performed with age-matched mice 9-10 weeks old.
[0078] The abdominal hair of mice was removed with electric clippers. The mice having had their ears covered with aluminum foil were then exposed to a bank of four unfiltered FS40 sunlamps (National Biological Corp.) at a dose of 2000 J/m 2 . Approximately 65% of the energy emitted from these lamps was within the UVB range (280-320) and the peak emission was 313 nm. Immediately after the UVB exposure, Aquaphor (vehicle) alone or tested compound in Aquaphor at a 1:1 ratio was applied onto the abdominal skin of the mice. The mice were then sensitized on their shaved abdominal skin with 50 μL of 0.3% dinitrofluorobenzene (DNFB), 3 days after the UVB exposure. Six days after sensitization, the mice were challenged by painting 5 μL of 0.2% DNFB on both the dorsal and ventral surface of each ear. Ear thickness was measured using an engineers' micrometer immediately before challenge and 24 hours later. Specific ear swelling was determined by subtracting values obtained from mice that were challenged but not sensitized (blank group). Each treatment group contained five mice. Two additional control groups were included in each experiment—a positive control group and a suppressed group. The positive control received no UVB radiation and no treatment, but sensitized and challenged (100% response). The suppressed group of mice received UVB radiation and no treatment, but were sensitized and challenged (0% response). The results are set forth in FIG. 8.
Example 9
Determination of Immuno-10 Suppressed UVB-Induced TNF-α Release
[0079] Human epidermoid carcinoma cells (KB) were plated at 2×10 6 cells per 100 mm dish. After the cells reached confluence (about 2 days), they were washed three times with PBS and exposed to UVB radiation at 300 J/m 2 . The cells were then washed once with PBS and incubated in 5 mL DMEM/0.2% FBS with or without Immuno-10 for 1 hour. The cells were washed once more with PBS and further incubated in a growth medium overnight. The next day the medium was collected and centrifuged at 2500 rpm for 10 minutes at 4° C. The TNF-α released into the supernatant was determined by ELISA. The results are set forth in FIG. 9.
Example 10
Determination of Immuno-10 Stimulated Macrophage Activation
[0080] Resident mouse peritoneal macrophages were isolated from ICR mice and plated at 200,000 cells per well in a 96-well plate. The cells were washed three times to remove non-adherent cells after a 2 hour incubation. Macrophages were then incubated with or without Immuno-10 overnight. The TNF-α released into the media was determined by ELISA. Lipopolysaccharides (LPS) were used as a positive control. The results are set forth in FIG. 10.
Example 11
Determination of Immuno-10 Stimulated Cell Proliferation (MTT)
[0081] Baby hamster kidney cell line (BHK cells) were plated at 5000 cells per well in a 96-well plate. The cells were incubated with or without Immuno-10 for 3 days in the tissue culture incubator. The cells were then incubated with 1 mg/mL MTT (3-(4,5-dimethylthiazol-2-yl)-2,3-diphenyltetrazolium bromide, Thiazolyl blue) for 4.5 hours. The absorbance at 570-630 nm was determined after the cells were extracted with 100 μL of 10% SD in 0.01N HCl. Fibroblast growth factor (FGF) was included as a positive control. The results are set forth in FIG. 11. | The present invention provides a rapid and efficient method for the preparation and isolation of biologically active polysaccharides from Aloe. The present invention includes the activated mixture of polysaccharides (referred to herein as “Immuno-10”), produced by the methods of the invention. The invention also includes the use of the polysaccharides as immunostimulating, immunomodulating and wound healing agents. The resulting immunomodulatory complex has a higher activity and is more stable than bulk carbohydrates isolated using prior art alcohol precipitation schemes. | 2 |
[0001] This application claims priority to U.S. Provisional Application No. 61/925,608 filed Jan. 9, 2014, the contents of which are hereby incorporated by reference in their entirety.
TECHNICAL FIELD
[0002] The present invention relates to novel compounds useful as CK1 inhibitors, pharmaceutical compositions comprising said compounds and methods for inhibiting CK1 as well as methods of treatment of CK1 related disorders, comprising administering a therapeutically effective amount of a CK1 inhibitor to a patient in need thereof.
BACKGROUND OF THE INVENTION
[0003] Alzheimer's disease (AD) is an irreversible, progressive brain disease characterized by the loss of cognitive functioning, e.g., memory and reasoning, and behavioral abilities. AD is estimated to affect more than 25 million people in the world and is reported in the 2010 World Alzheimer Report to have annual societal costs of US$604 billion, or 1% of the aggregated worldwide Gross Domestic Product (GDP). Existing AD medications aim to treat symptoms of AD only and do so rather poorly. Existing AD medications do not address the progression of the disease. New therapeutic agents that slow (or reverse) the disease and that target multiple aspects of the disorder are urgently needed.
[0004] Studies have shown that the etiology of AD includes a range of clear genetic predispositions involving amyloid precursor protein (APP), Tau phosphorylation, gamma-secretase (GS), apolipoprotein E (ApoE) and genes involved in circadian rhythms. There is strong evidence which indicates the importance of Tau hyper-phosphorylation, excessive amyloid beta (Aβ) formation and desynchrony of circadian rhythms in Alzheimer's disease. There is also clear evidence of a cell loss in the suprachiasmatic nucleus, the brain region involved in regulating circadian rhythms that coincides with development of the dementia stage of AD. AD patients suffer a plethora of symptoms including serious and progressive cognitive decline, sleep disturbances and agitation.
[0005] Casein Kinase 1 is a member of a unique class of protein serine/threonine kinases that are only distantly related to other kinase families. Comparing CK1 sequence identities to other kinase families, glycogen synthase kinase 3 (GSK3) is the closest related kinase outside the CK1 family and is only 20% identical in the catalytic domain. The CK1 family has seven isoforms with various splice variants. The role of CK1 in AD is substantially documented in recent reviews. See Buee et al., Brain Res. Rev . (2000) 33(1):95-130; See also Perez et al., Med. Res. Rev . (2010) 31(6):924-54. It has been observed that CK1 delta mRNA is elevated 30-fold in the hippocampus of AD patients' brains. Yasojima et al., Brain Res . (2000) 865(1):116-20. The beneficial effect of CK1 inhibitors to reverse AB formation has also been shown. Flajolet et al., Proc. Natl. Acad. Sci . U.S.A. (2007) 104(10):4159-64. With regard to the phosphorylation of various Tau forms, there are multiple sites of phosphorylation of Tau and a number of putative Tau kinases are involved. Although the role of various kinases in this process is complex, the importance of critical priming kinases is generally accepted as driving the hyper-phosphorylation co-incident with the formation of paired helical filaments (PHF) that are the universal pathology associated with AD. It is well documented that CK1 is a “major Tau kinase” with priming functions and is associated with paired helical filaments (PHF). Hanger et al., J. Biol. Chem . (2007) 282(32):23645-54. Most importantly, there is substantial evidence for a fundamental role of CK1 controlling circadian rhythm and metabolic state through phosphorylation and regulation of a series of transcription factors including CLOCK, BMAL-1, and Perl-3; with CK1 and CK2 collectively considered the “clock genes”. Ebisawa T., J. Pharmacol. Sci . (2007) 103(2):150-4. CK1 delta and epsilon gene variations are also associated with circadian rhythms changes.
[0006] Highly specific CK1 inhibitors have been developed and have served to further validate the role of CK1 in AD related pathologies. Several examples of potent and selective inhibitors are known. Using potent and selective CK1 inhibitors in rodent and monkey animal models, profound influences on phase shifts in circadian rhythms are discovered that substantially validate the hypothesis of CK1 involvement in the biological clock. Sprouse et al., Psychopharmacology (Berl) (2010) 210(4):569-76; Sprouse et al., Psychopharmacology (Berl) (2009) 204(4):735-42. All of these studies therefore support the critical role of CK1 as therapeutic target in AD.
[0007] In view of the important role of CK1, further potent and selective CK1 inhibitors are needed in the fight against AD and other CK1 related diseases.
SUMMARY OF THE INVENTION
[0008] The current invention provides novel compounds useful as CK1 inhibitors. Therefore, in the first aspect, the invention provides a compound of Formula I:
[0000]
[0000] wherein:
(i) R 3 is halo (e.g., fluoro); and (ii) R 1 and R 2 together form a piperazine ring wherein said piperazine is optionally substituted with a C 1-6 alkyl;
in free or salt form.
[0011] In a further embodiment of the first aspect, the invention provides the compound of Formula I as follows:
1.1. the compound of Formula I, wherein the piperazine ring is substituted with a C 1-6 alkyl (e.g., methyl), for example 4-methylpiperazin-1-yl; 1.2. the compound of Formula I or formula 1.1, wherein R 3 is fluoro; 1.3. the compound of Formula I, which is:
[0000]
[0000] in free or salt form.
[0015] In the second aspect, the invention provides a compound of Formula II:
[0000]
[0000] wherein:
(i) R 1 , R 2 , R 3 and R 4 are independently selected from the group consisting of H, C 1-6 alkyl (e.g., methyl) and halo (e.g., chloro); (ii) A is C 1-4 alkylene (e.g., methylene or ethylene); (iii) B is a monocyclic or bicyclic aryl or heteroaryl (e.g., phenyl, naphthyl or pyridyl), optionally substituted with —N(H)(R a ), wherein R a is —C(O)—C 1-6 alkyl (e.g., —C(O)CH 3 );
in free or salt form.
[0019] In a further embodiment of the second aspect, the invention provides the compound of Formula II as follows:
2.1. the compound of Formula II, wherein R 1 , R 2 , R 3 and R 4 are independently selected from the group consisting of H, C 1-6 alkyl (e.g., methyl) and halo (e.g., chloro); 2.2. the compound of Formula II or formula 2.1, wherein R 1 , R 2 , R 3 and R 4 are independently H; 2.3. the compound of Formula II or formula 2.1 or 2.2, wherein R 1 , R 2 , R 3 and R 4 are independently C 1-6 alkyl (e.g., methyl); 2.4. the compound of Formula II or any one of formulae 2.1-2.3, wherein R 1 , R 2 , R 3 and R 4 are independently halo (e.g., chloro); 2.5. the compound of Formula II or any one of formulae 2.1-2.4 wherein R 3 and R 4 are independently H or methyl; 2.6. the compound of Formula II or any one of formulae 2.1-2.5, wherein R 3 is halo (e.g., chloro) or C 1-6 alkyl (e.g., methyl); 2.7. the compound of Formula II or any one of formulae 2.1-2.6, wherein A is C 1-4 alkylene (e.g., methylene or ethylene); 2.8. the compound of Formula II or any one of formulae 2.1-2.6, wherein A is methylene; 2.9. the compound of Formula II or any one of formulae 2.1-2.6, wherein A is ethylene; 2.10. the compound of Formula II or any one of formulae 2.1-2.9, wherein B is a mono-cyclic or bicyclic aryl or heteroaryl (e.g., phenyl, naphthyl or pyridyl), optionally substituted with —N(H)(R a ), wherein R a is —C(O)—C 1-6 alkyl (e.g., —C(O)CH 3 ); 2.11. the compound of Formula II or any one of formulae 2.1-2.9, wherein B is a monocyclic or bicyclic heteroaryl (e.g., pyridyl); 2.12. the compound of Formula II or any one of formulae 2.1-2.9, wherein B is pyridyl (e.g., pyrid-3-yl); 2.13. the compound of Formula II or any one of formulae 2.1-2.9, wherein B is a monocyclic or bicyclic aryl (e.g., phenyl or naphthyl) optionally substituted with —N(H)(R a ), wherein R a is —C(O)—C 1-6 alkyl (e.g., —C(O)CH 3 ); 2.14. the compound of Formula II or any one of formulae 2.1-2.9, wherein B is a monocyclic or bicyclic aryl (e.g., phenyl or naphthyl) substituted with —N(H)(R a ), wherein R a is —C(O)—C 1-6 alkyl (e.g., —C(O)CH 3 ); 2.15. the compound of Formula II or any of the foregoing formulae, wherein:
(i) R 1 , R 2 , R 3 and R 4 are H; (ii) A is C 1-4 alkylene (e.g., methylene); (iii) B is a monocyclic or bicyclic heteroaryl (e.g., pyridyl, for example pyrid-3-yl);
2.16. the compound of Formula II, selected from the group consisting of:
[0000]
[0000] in free or salt form.
[0039] In the third aspect, the invention provides a compound of Formula III:
[0000]
[0000] wherein:
(i) R 1a , R 1b , R 1c , R 1d and R 1e are independently selected from the group consisting of H, halo (e.g., bromo or fluoro), hydroxy and —N(R 4 )(R 5 ); (ii) R 2a , R 2b , R 2c and R 2d are independently selected from the group consisting of H, C 1-4 alkyl (e.g., methyl, ethyl, tert-butyl, alkynyl, i.e., —CCH) and C 1-4 alkylcarbonyl (e.g., —C(O)—CH 3 ), provided R 2a is not methyl; (iii) R 3 is selected from the group consisting of H, hydroxy and —NH 2 ; (iv) R 4 and R 5 are independently selected from the group consisting of H, C 1-4 alkyl (e.g., methyl) and C 1-4 alkylcarbonyl (e.g., —C(O)—CH 3 ); (v) provided that when R 1a , R 1b , R 1c , R 1d , R 1c and a R 3 are H, then R 2a , R 2b , R 2c and R 2d are independently H or an unsaturated C 2-4 alkyl (e.g., alkynyl);
in free or salt form.
[0045] In a further embodiment of the third aspect, the invention provides the compound of Formula III as follows:
3.1. the compound according to Formula III, wherein R 1a , R 1b , R 1c , R 1d and R 1e are independently selected from the group consisting of H, halo (e.g., bromo or fluoro), hydroxy and —N(R 4 )(R 5 ); 3.2. the compound according to Formula III or formula 3.1, wherein R 1a , R 1b , R 1c , R 1d and R 1e are independently H; 3.3. the compound according to Formula III or formula 3.1, wherein R 1a , R 1b , R 1c , R 1d and R 1e are all H, or R 1a , R 1b , R 1d and R 1e are all H and R 1c is selected from the group consisting of halo (e.g., bromo or fluoro), hydroxy and —N(R 4 )(R 5 ); 3.4. the compound according to Formula III or formula 3.1, 3.2 or 3.3, wherein R 1a , R 1b , R 1c , R 1d and R 1e are independently halo (e.g., bromo or fluoro); 3.5. the compound according to Formula III or any one of formulae 3.1-3.4, wherein R 1a , R 1b , R 1c , R 1d and R 1e are independently hydroxy; 3.6. the compound according to Formula III or any one of formulae 3.1-3.5, wherein R 1a , R 1b , R 1c , R 1d and R 1e are independently —N(R 4 )(R 5 ); 3.7. the compound according to Formula III, wherein R 1a , R 1b , R 1d and R 1e are H and R 1c is selected from the group consisting of halo (e.g., bromo or fluoro), hydroxy and —N(R 4 )(R 5 ), for example R 1c is bromo, fluoro, hydroxy, dimethylamino or —NHC(O)CH 3 ; 3.8. the compound according to Formula III or any one of formulae 3.6 or 3.7, wherein R 4 and R 5 are independently selected from the group consisting of H, C 1-4 alkyl (e.g., methyl), and C 1-4 alkylcarbonyl (e.g., —C(O)—CH 3 ); 3.9. the compound according to Formula III or formula 3.6, 3.7 or 3.8, wherein R 4 or R 5 is H; 3.10. the compound according to Formula III or any one of formulae 3.6-3.9, wherein R 4 or R 5 is C 1-4 alkyl (e.g., methyl); 3.11. the compound according to Formula III or any one of formulae 3.6-3.10, wherein R 4 or R 5 is C 1-4 alkylcarbonyl (e.g., —C(O)—CH 3 ); 3.12. the compound according to Formula III or any one of formulae 3.6-3.10, wherein R 4 is H and R 5 is C 1-4 alkyl (e.g., methyl); 3.13. the compound according to Formula III or formula 3.6, 3.7 or 3.8, wherein R 4 and R 5 are both C 1-4 alkyl (e.g., methyl); 3.14. the compound according to Formula III or any one of formulae 3.1-3.13, wherein R 1a , R 1b , R 1c , R 1d and R 1e are independently selected from the group consisting of halo (e.g., bromo or fluoro), hydroxy and —N(R 4 )(R 5 ); 3.15. the compound according to Formula III or any one of formulae 3.1-3.14, wherein R 2a , R 2b , R 2c and R 2d are independently selected from the group consisting of H, C 1-4 alkyl (e.g., methyl, ethyl, tert-butyl or alkynyl, i.e., —CCH) and C 1-4 alkylcarbonyl (e.g., —C(O)—CH 3 ), provided R 2a is not methyl; 3.16. the compound according to Formula III or any one of the preceding formulae, wherein R 2a , R 2b , R 2c and R 2d are independently H; 3.17. the compound according to Formula III or any one of the preceding formulae, wherein R 2a , R 2b , R 2c and R 2d are independently H or C 1-4 alkyl (e.g., methyl, ethyl, tert-butyl or alkynyl, i.e., —CCH), provided R 2a is not methyl; 3.18. the compound according to Formula III or any one of the preceding formulae, wherein R 2a , R 2b , R 2c and R 2d are independently H or C 1-4 alkylcarbonyl (e.g., —C(O)—CH 3 ); 3.19. the compound according to Formula III or any one of the preceding formulae, wherein R 2a is H; 3.20. the compound according to Formula III or any one of the preceding formulae, wherein R 2 is selected from the group consisting of C 1-4 alkyl (e.g., methyl, ethyl, tert-butyl or alkynyl, i.e., —CCH) and C 1-4 alkylcarbonyl (e.g., —C(O)—CH 3 ); 3.21. the compound according to Formula III or any one of the preceding formulae, wherein R 2c is C 1-4 alkyl (e.g., methyl, ethyl, tert-butyl or alkynyl, i.e., —CCH); 3.22. the compound according to Formula III or any one of the preceding formulae, wherein R 2d is C 1-4 alkyl (e.g., alkynyl, i.e., —CCH); 3.23. the compound according to Formula III or any one of the preceding formulae, wherein R 3 is selected from the group consisting of H, hydroxy and —NH 2 ; 3.24. the compound according to Formula III or any one of the preceding formulae, wherein R 3 is H; 3.25. the compound according to Formula III or any one of the preceding formulae, wherein R 3 is —OH; 3.26. the compound according to Formula III or any one of the preceding formulae, wherein R 3 is —NH 2 ; 3.27. the compound according to Formula III, wherein:
(i) R 1a , R 1b , R 1d and R 1e are H and R 1c is —N(R 4 )(R 5 ); (ii) R 2a , R 2b and R 2d are H and R 2c is C 1-4 alkyl (e.g., ethyl); (iii) R 3 is H; (iv) R 4 is H and R 5 is C 1-4 alkylcarbonyl (e.g., —C(O)—CH 3 );
3.28. the compound according to Formula III selected from any of the following:
[0000]
[0000] in free or salt form.
[0078] The compounds of the invention are useful as Casein Kinase 1 (CK1) inhibitors, particularly CK1 delta (CK1δ) and/or CK1 epsilon (CK1ε) inhibitors. CK1 delta mRNA has been shown to be elevated by 30-fold in the hippocampus of Alzheimer's disease patients' brain. The beneficial effect of CK1 inhibitors to reverse AB formation has also been established. Further, CK1 has been shown to be a major Tau kinase with priming functions and is associated with paired helical filaments (PHF), which are the universal pathology associated with Alzheimer's Disease. CK1 over-expression has also been shown to increase amyloid beta formation while CK1 inhibitors lower amyloid beta formation. There is also evidence of CK1 controlling circadian rhythm and metabolic state through phosphorylation and regulation of a series of transcription factors including CLOCK, BMAL-1 and Perl-3. In particular, CK1δ and CK1ε are associated with circadian rhythms changes. Therefore, the role of CK1 in Alzheimer's disease is well documented and CK1 inhibitors of the invention are particularly useful as a therapeutic agent.
[0079] Therefore, in the fourth aspect, the invention provides a pharmaceutical composition (Composition 1) comprising a CK1 inhibitor of the current invention as hereinbefore described, in free or pharmaceutically acceptable salt form, in combination or association with a pharmaceutically acceptable diluent or carrier.
[0080] In the fifth aspect, the invention provides a method (Method 1) for inhibiting CK1 activity, e.g., inhibiting CK1δ and/or CK1ε activity, comprising contacting CK1, particularly CK1δ and/or CK1ε, with any one of the compounds of the current invention as described herein, or a pharmaceutical composition of the current invention.
[0081] In the sixth aspect, the invention provides a method (Method 2) for the treatment or prophylactic treatment, control or management of a disorder that can be benefited from CK1 inhibition, such as disorders related to abnormally hyperphosphorylated Tau state, e.g., Alzheimer's disease, cancer, attention deficit hyperactive disorder (ADHD), disorder associated with the desynchrony of circadian rhythms, for example sleep disorders (e.g., advanced sleep phase syndrome or delayed shift phase syndrome, jet lag syndrome, shift work sleep disorder), mood disorders, depressive disorders, e.g., depression, bipolar disorder (bipolar I and bipolar II disorder), or desynchrony of circadian rhythms associated with Alzheimer's disease, dementia, Down syndrome, frontotemporal dementia with Parkinsonism linked to chromosome 17 (FTDP-17), amyotrophic lateral sclerosis, corticobasal degeneration, dementia pugilistica, Pick disease, tangle-only dementia, acute neurological and psychiatric disorders such as cerebral deficits subsequent to cardiac bypass surgery and grafting, stroke, cerebral ischemia, spinal cord trauma, head trauma, perinatal hypoxia, cardiac arrest, hypoglycemic neuronal damage, AIDS-induced dementia, vascular dementia, mixed dementias, age-associated memory impairment, Huntington's Chorea, ocular damage, retinopathy, cognitive disorders, including cognitive disorders associated with schizophrenia and bipolar disorders, idiopathic and drug-induced Parkinson's disease, muscular spasms and disorders associated with muscular spasticity including tremors, epilepsy, convulsions, migraine, migraine headache, urinary incontinence, substance tolerance, substance withdrawal, withdrawal from opiates, nicotine, tobacco products, alcohol, benzodiazepines, cocaine, sedatives, and hypnotics, psychosis, mild cognitive impairment, amnestic cognitive impairment, multi-domain cognitive impairment, obesity, schizophrenia, anxiety, generalized anxiety disorder, social anxiety disorder, panic disorder, post-traumatic stress disorder, obsessive compulsive disorder, mood disorders, depression, mania, bipolar disorders, trigeminal neuralgia, hearing loss, tinnitus, macular degeneration of the eye, emesis, brain edema, pain, acute and chronic pain states, severe pain, intractable pain, neuropathic pain, post-traumatic pain, tardive dyskinesia, narcolepsy, autism, Asperger's disease, and conduct disorder in a mammal, comprising administering to a subject in need thereof an effective amount of a CK1 inhibitor of the current invention as hereinbefore described, preferably a CK1δ and/or CK1ε inhibitor, in free or pharmaceutically acceptable salt form.
[0082] In the seventh aspect, the invention provides a pharmaceutical composition (Composition 1) comprising a CK1 inhibitor of the current invention as hereinbefore described, in free or pharmaceutically acceptable salt form, in combination or association with a pharmaceutically acceptable diluent or carrier, for use (in the manufacture of a medicament) for the treatment or prophylactic treatment, control or management of a disorder that can be benefited from CK1 inhibition, such as disorders related to abnormally hyperphosphorylated Tau state, e.g., Alzheimer's disease, cancer, attention deficit hyperactive disorder (ADHD), disorder associated with the desynchrony of circadian rhythms, for example sleep disorders (e.g., advanced sleep phase syndrome or delayed shift phase syndrome, jet lag syndrome, shift work sleep disorder), mood disorders, depressive disorders, e.g., depression, bipolar disorder (bipolar I and bipolar II disorder), or desynchrony of circadian rhythms associated with Alzheimer's disease, dementia, Down syndrome, frontotemporal dementia with Parkinsonism linked to chromosome 17 (FTDP-17), amyotrophic lateral sclerosis, corticobasal degeneration, dementia pugilistica, Pick disease, tangle-only dementia, acute neurological and psychiatric disorders such as cerebral deficits subsequent to cardiac bypass surgery and grafting, stroke, cerebral ischemia, spinal cord trauma, head trauma, perinatal hypoxia, cardiac arrest, hypoglycemic neuronal damage, AIDS-induced dementia, vascular dementia, mixed dementias, age-associated memory impairment, Huntington's Chorea, ocular damage, retinopathy, cognitive disorders, including cognitive disorders associated with schizophrenia and bipolar disorders, idiopathic and drug-induced Parkinson's disease, muscular spasms and disorders associated with muscular spasticity including tremors, epilepsy, convulsions, migraine, migraine headache, urinary incontinence, substance tolerance, substance withdrawal, withdrawal from opiates, nicotine, tobacco products, alcohol, benzodiazepines, cocaine, sedatives, and hypnotics, psychosis, mild cognitive impairment, amnestic cognitive impairment, multi-domain cognitive impairment, obesity, schizophrenia, anxiety, generalized anxiety disorder, social anxiety disorder, panic disorder, post-traumatic stress disorder, obsessive compulsive disorder, mood disorders, depression, mania, bipolar disorders, trigeminal neuralgia, hearing loss, tinnitus, macular degeneration of the eye, emesis, brain edema, pain, acute and chronic pain states, severe pain, intractable pain, neuropathic pain, post-traumatic pain, tardive dyskinesia, narcolepsy, autism, Asperger's disease, and conduct disorder in a mammal.
[0083] In the eighth aspect, the invention provides use of a CK1 inhibitor of the current invention, in free or pharmaceutically acceptable salt form, (in the manufacture of a medicament) for the treatment or prophylactic treatment, control or management of a disorder that can be benefited from CK1 inhibition, such as disorders related to abnormally hyperphosphorylated Tau state, e.g., Alzheimer's disease, cancer, attention deficit hyperactive disorder (ADHD), disorder associated with the desynchrony of circadian rhythms, for example sleep disorders (e.g., advanced sleep phase syndrome or delayed shift phase syndrome, jet lag syndrome, shift work sleep disorder), mood disorders, depressive disorders, e.g., depression, bipolar disorder (bipolar I and bipolar II disorder), or desynchrony of circadian rhythms associated with Alzheimer's disease, dementia, Down syndrome, frontotemporal dementia with Parkinsonism linked to chromosome 17 (FTDP-17), amyotrophic lateral sclerosis, corticobasal degeneration, dementia pugilistica, Pick disease, tangle-only dementia, acute neurological and psychiatric disorders such as cerebral deficits subsequent to cardiac bypass surgery and grafting, stroke, cerebral ischemia, spinal cord trauma, head trauma, perinatal hypoxia, cardiac arrest, hypoglycemic neuronal damage, AIDS-induced dementia, vascular dementia, mixed dementias, age-associated memory impairment, Huntington's Chorea, ocular damage, retinopathy, cognitive disorders, including cognitive disorders associated with schizophrenia and bipolar disorders, idiopathic and drug-induced Parkinson's disease, muscular spasms and disorders associated with muscular spasticity including tremors, epilepsy, convulsions, migraine, migraine headache, urinary incontinence, substance tolerance, substance withdrawal, withdrawal from opiates, nicotine, tobacco products, alcohol, benzodiazepines, cocaine, sedatives, and hypnotics, psychosis, mild cognitive impairment, amnestic cognitive impairment, multi-domain cognitive impairment, obesity, schizophrenia, anxiety, generalized anxiety disorder, social anxiety disorder, panic disorder, post-traumatic stress disorder, obsessive compulsive disorder, mood disorders, depression, mania, bipolar disorders, trigeminal neuralgia, hearing loss, tinnitus, macular degeneration of the eye, emesis, brain edema, pain, acute and chronic pain states, severe pain, intractable pain, neuropathic pain, post-traumatic pain, tardive dyskinesia, narcolepsy, autism, Asperger's disease, and conduct disorder in a mammal.
[0084] In one embodiment of the sixth, seventh and eighth aspects, the disorder is selected from the group consisting of Alzheimer's disease, attention deficit hyperactive disorder (ADHD), disorder associated with the desynchrony of circadian rhythms, for example sleep disorders, e.g., advanced sleep phase syndrome or delayed shift phase syndrome), mood disorders, depressive disorders, e.g., depression, bipolar disorder, or desynchrony of circadian rhythms associated with Alzheimer's disease. In another embodiment, the disorder is Alzheimer's disease.
[0085] In the ninth aspect, the invention provides CK1 tracer compounds useful for Gamma radiation-based imaging. Two commonly employed gamma radiation-based imaging techniques are Positron Emission Tomography (referred to as PET) and Single Photon Emission Computed Tomography (referred to as SPECT). Therefore, CK1 tracer compounds of the current invention comprise (i) a CK1 inhibitor of the current invention as hereinbefore described, in free or pharmaceutically acceptable salt form; and (ii) a radionuclide chemically bound to said CK1 inhibitor. Examples of isotopes useful in gamma radiation-based imaging include Carbon-11 (referred to as 11C or C11), Fluorine-18 (referred to as 18F or F18), Technetium-99m (referred to as 99mTc or Tc99m), Indium-111 (referred to as 111In or In111) and Iodine-123 (referred to as 123I or I123).
[0086] Therefore, in a further embodiment of the ninth aspect, the radionuclide is selected from Carbon-11 (referred to as 11 C or C 11 ), Fluorine-18 (referred to as 18 F or F 18 ), Technetium-99m (referred to as 99 mTc or Tc 99 m), Indium-111 (referred to as 111 In or In 111 ) and Iodine-123 (referred to as 123 I or I 123 ), preferably 11 C or 18 F. For example, the CK1 tracer compound of the invention is the compound of Formula I selected from any of the following:
[0000]
[0000] in free or salt form.
[0087] In another embodiment of the ninth aspect, the invention provides CK1 tracer compounds comprising halonium salt of a compound selected from the following:
[0088] a) a compound of Formula I:
[0000]
[0000] wherein:
(i) R 3 is F 18 ; and (ii) R 1 and R 2 together form a piperazine ring wherein said piperazine is optionally substituted with a C 1-6 alkyl;
in free or salt (e.g., pharmaceutically acceptable salt) form;
[0091] b) a compound of Formula II:
[0000]
[0000] wherein:
(i) R 1 , R 2 , R 3 and R 4 are independently F 18 or I 123 ; (ii) A is C 1-4 alkylene (e.g., methylene or ethylene); (iii) B is a monocyclic or bicyclic aryl or heteroaryl (e.g., phenyl, naphthyl or pyridyl), optionally substituted with —N(H)(R a ), wherein R a is —C(O)—C 1-6 alkyl (e.g., —C(O)CH 3 );
in free or salt (e.g., pharmaceutically acceptable salt) form; and
[0095] c) a compound of Formula III:
[0000]
[0000] wherein:
(i) R 1a , R 1b , R 1c , R 1d and R 1e are independently F 18 ; (ii) R 2a , R 2b , R 2c and R 2d are independently selected from the group consisting of H, C 1-4 alkyl (e.g., methyl, ethyl, tert-butyl, alkynyl, i.e., —CCH) and C 1-4 alkylcarbonyl (e.g., —C(O)—CH 3 ), provided R 2a is not methyl; (iii) R 3 is selected from the group consisting of H, hydroxy and —NH 2 ; (iv) provided that when R 1a , R 1b , R 1c , R 1d and R 1e and R 3 are H, then R 2a , R 2b , R 2c and R 2d are independently H or an unsaturated C 2-4 alkyl (e.g., alkynyl);
in free or salt (e.g., pharmaceutically acceptable) form.
[0100] In another embodiment of the ninth aspect, the invention provides CK1 tracer compounds comprising a compound selected from the following:
[0101] a) a compound of Formula I:
[0000]
[0000] wherein:
(iii) R 3 is F 18 ; and (iv) R 1 and R 2 together form a piperazine ring wherein said piperazine is optionally substituted with a C 1-6 alkyl;
in free or salt (e.g., pharmaceutically acceptable salt) form;
[0104] b) a compound of Formula II:
[0000]
[0000] wherein:
(iv) R 1 , R 2 , R 3 and R 4 are independently F 18 or I 123 ; (v) A is C 1-4 alkylene (e.g., methylene or ethylene); (vi) B is a monocyclic or bicyclic aryl or heteroaryl (e.g., phenyl, naphthyl or pyridyl), optionally substituted with —N(H)(R a ), wherein R a is —C(O)—C 1-6 alkyl (e.g., —C(O)CH 3 );
in free or salt (e.g., pharmaceutically acceptable salt) form; and
[0108] c) a compound of Formula III:
[0000]
[0000] wherein:
R 1a , R 1b , R 1c , R 1d and R 1e are independently F 18 ; (vi) R 2a , R 2b , R 2a and R 2d are independently selected from the group consisting of H, C 1-4 alkyl (e.g., methyl, ethyl, tert-butyl, alkynyl, i.e., —CCH) and C 1-4 alkylcarbonyl (e.g., —C(O)—CH 3 ), provided R 2a is not methyl; (vii) R 3 is selected from the group consisting of H, hydroxy and —NH 2 ; (viii) provided that when R 1a , R 1b , R 1c , R 1d , R 1e and R 3 are H, then R 2a , R 2b , R 2c and R 2d are independently H or an unsaturated C 2-4 alkyl (e.g., alkynyl);
in free or salt (e.g., pharmaceutically acceptable) form.
DETAILED DESCRIPTION OF THE INVENTION
[0113] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to limit the scope of the present invention in any way.
[0114] Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the preferred methods, devices and materials are now described. All publications mentioned herein are incorporated by reference for the purpose of describing and disclosing the materials and methodologies that are reported in the publication which might be used in connection with the invention.
[0115] As used herein and in the appended claims, the singular forms “a”, “an”, and “the” include plural reference unless the context clearly dictates otherwise. Thus, for example, reference to the “antibody” is a reference to one or more antibodies and equivalents thereof known to those skilled in the art, and so forth.
[0116] The term “CK1” refers to the polypeptide Casein Kinase 1. The term refers to any and all forms of this polypeptide including, but not limited to, homologs, partial forms, isoforms, precursor forms, the full length polypeptide, fusion proteins containing the CK1 sequence or fragments of any of the above, from human or any other species. Numerous isoforms of CK1 have been identified and include, but are not limited to α, γ1, γ2, γ3, δ, ε1, ε2, and ε3 isoforms. CK1 and its various isoforms are familiar to one of skill in the art as they have been disclosed in the art. It is also contemplated that the term refers to CK1 isolated from naturally occurring sources of any species such as genomic DNA libraries as well as genetically engineered host cells comprising expression systems, or produced by chemical synthesis using, for instance, automated peptide synthesizers or a combination of such methods. Means for isolating and preparing such polypeptides are well understood in the art.
[0117] If not otherwise specified or clear from context, the following terms as used herein have the following meetings:
a. “Alkyl” as used herein is a saturated or unsaturated hydrocarbon moiety, preferably saturated, preferably one to six carbon atoms in length, in some instance one to four carbon atoms in length, which may be linear or branched, and may be optionally substituted, e.g., mono-, di-, or tri-substituted, e.g., with halogen (e.g., chloro or fluoro) or hydroxy. b. “Cycloalkyl” as used herein is a fully or partially saturated or unsaturated nonaromatic hydrocarbon moiety, preferably comprising three to nine carbon atoms, at least some of which form a nonaromatic mono- or bicyclic, or bridged cyclic structure, and which may be optionally substituted, e.g., with halogen (e.g., chloro or fluoro) or hydroxy. c. “Aryl” as used herein is a monocyclic or bicyclic aromatic hydrocarbon, preferably phenyl, optionally substituted, e.g., with alkyl (e.g., methyl), halogen (e.g., chloro or fluoro), haloalkyl (e.g., trifluoromethyl) or hydroxy. d. “Heteroaryl” as used herein is a monocyclic or bicyclic aromatic moiety wherein one or more of the atoms making up the aromatic ring is sulfur, oxygen or nitrogen rather than carbon, e.g., pyridyl or thiadiazolyl, which may be optionally substituted, e.g., with alkyl, halogen, haloalkyl or hydroxy. e. “Optionally substituted” is intended to be substituted or unsubstituted. In one particular embodiment, the substituent is unsubstituted. In another embodiment, the substituent is substituted. For example, the phrase “piperazine is optionally substituted with a C 1-6 alkyl” is intended to cover unsubstituted piperazine or a piperazine substituted with a C 1-6 alkyl.
[0123] The phrase “CK1 inhibitors of the invention” or “the compounds of the invention” refers to any of the compounds disclosed herein, particularly the compounds of formulae I, II and III or any of formulae 1.1-1.3, 2.1-2.16 and 3.1-3.28, in free or salt form. These compounds preferably inhibit CK1, particularly CK1δ and/or CK1ε with a Ki of less than 2 μM, preferably less than 500 nM, more preferably less than 100 nM as described or similarly described in Example 14 or inhibit 50% of CK1 at 10 μM as described or similarly described in Example 15.
[0124] The compounds of the invention may exist in free or salt form, e.g., as acid addition salts. In this specification unless otherwise indicated language such as compounds of the invention is to be understood as embracing the compounds in any form, for example free or acid addition salt form, or where the compounds contain acidic substituents, in base addition salt form. The compounds of the invention are intended for use as pharmaceuticals, therefore pharmaceutically acceptable salts are preferred. Salts which are unsuitable for pharmaceutical uses may be useful, for example, for the isolation or purification of free Compounds of the Invention or their pharmaceutically acceptable salts, are therefore also included.
[0125] The compounds of the invention may in some cases also exist in prodrug form. For example when the compounds contain hydroxy or carboxy substituents, these substituents may form physiologically hydrolysable and acceptable esters. As used herein, “physiologically hydrolysable and acceptable ester” means esters of Compounds of the Invention which are hydrolysable under physiological conditions to yield acids (in the case of compounds of the invention which have hydroxy substituents) or alcohols (in the case of compounds of the invention which have carboxy substituents) which are themselves physiologically tolerable at doses to be administered. As will be appreciated the term thus embraces conventional pharmaceutical prodrug forms.
[0126] Some individual compounds within the scope of this invention may contain double bonds. Representations of double bonds in this invention are meant to include both the E and the Z isomer of the double bond. In addition, some compounds within the scope of this invention may contain one or more asymmetric centers. This invention includes the use of any of the optically pure stereoisomers as well as any combination of stereoisomers.
[0127] As will be appreciated by those skilled in the art, the compounds of the invention, for example, the acyl guanidine compounds of Formula II, may exhibit tautomerization. Therefore, the compounds of the invention are to be understood as embracing both the structures as set forth herein (e.g., the compounds of formula 2.16) as well as their tautomeric variants (e.g., isomers in which the N—N double bond of the guanidine group is located in each possible position).
[0128] The words “treatment” and “treating” are to be understood accordingly as embracing treatment or amelioration of symptoms of disease as well as treatment of the cause of the disease.
[0129] “Subject” refers to any human or nonhuman organism.
[0130] It is contemplated herein that any compound with CK1 inhibitory activity, and not necessarily only those compounds that specifically inhibit only CK1, may prove to be useful therapeutics. For example, mixed CK1 inhibitors (e.g., compounds that can inhibit some isoforms of CK1 but not others) may be useful in the instant invention. Preferably, the compounds of the invention are the compounds that preferentially inhibit CK1δ and/or CK1ε, over the other CK1 isoforms.
[0131] It is contemplated herein that possible CK1 inhibitors may be metabolites of compounds disclosed herein. It is further contemplated that a CK1 inhibitors may be chemically substituted to optimize the activity of the modulator, e.g., to improve solubility, to improve delivery across the blood brain barrier, to improve lipophylicity, and/or to reduce cell toxicity. Chemical modifications of this sort may be achieved according to conventional methods familiar to one of skill in the art.
[0132] Similarly, it is contemplated herein that monitoring CK1 protein levels or kinase activity and/or detecting CK1 gene expression (mRNA levels) may be used as part of a clinical testing procedure, for example, to determine the efficacy of a given treatment regimen in accordance with any of the methods of the invention. For example, Alzheimer's patients undergoing conventional therapy may be evaluated and patients in whom CK1 levels, activity and/or gene expression levels are higher than desired (i.e. levels greater than levels in control patients) may be identified. Based on these data, the patient's dosage regimen may be adjusted and/or the type of drug administered may be modified. It is contemplated herein that monitoring a patient's levels of CK1 as described above may provide a quantitative assessment of a patient's physical and/or mental state.
[0133] Factors for consideration for optimizing a therapy for a patient include the particular condition being treated, the particular mammal being treated, the clinical condition of the individual patient, the site of delivery of the active compound, the particular type of the active compound, the method of administration, the scheduling of administration, and other factors known to medical practitioners. The therapeutically effective amount of an active compound to be administered will be governed by such considerations, and is the minimum amount necessary for the treatment of a CK1 related disorder, preferably Alzheimer's disease.
[0134] The pharmaceutical compositions of the present invention may be prepared using conventional diluents or excipients and techniques known in the galenic art. Thus oral dosage forms may include tablets, capsules, solutions, suspensions, spray-dried dispersions [e.g. Eudragit L100] and the like. The term “pharmaceutically acceptable carrier” as used herein is intended to include diluents such as saline and aqueous buffer solutions. The compounds of the invention may be administered in any convenient manner such as by injection (such as subcutaneous or intravenous), by oral administration, inhalation, transdermal application, intravaginal application, topical application, intranasal, sublingual or rectal administration. Depending on the route of administration, the active compound may be coated in a material to protect the compound from degradation by enzymes, acids and other natural conditions that may inactivate the compound.
[0135] The pharmaceutical compositions disclosed herein useful for treating CK1 related disorders, or disorders associated with abnormally hyperphosphorylated Tau state including Alzheimer's disease, are to be administered to a patient at therapeutically effective doses to treat symptoms of such disorders. A “therapeutically effective amount” is the amount of drug (e.g., CK1 inhibitor) sufficient to treat a CK1 related disorder or a disorder that can be benefited from the inhibition of CK1. For example, a therapeutically effective amount of a CK1 inhibitor may be an amount shown to inhibit, totally or partially, the progression of the condition or alleviate, at least partially, one or more symptoms of the condition. A therapeutically effective amount can also be an amount which is prophylactically effective. The amount which is therapeutically effective will depend upon the patient's size and gender, the condition to be treated, the severity of the condition and the result sought. For a given patient, a therapeutically effective amount may be determined by methods known to those of skill in the art.
[0136] A therapeutically effective dose refers to that amount of the compound that results in amelioration of symptoms in a patient. Toxicity and therapeutic efficacy of such compounds can be determined by standard pharmaceutical procedures in cell cultures or experimental animals.
[0137] Improvements in the physical and/or mental state of an individual suffering from Alzheimer's disease may be measured by techniques and combinations of techniques familiar to one of skill in the art, including but not limited to, Clinical Dementia Rating (CDR) assessment, the mini-mental state exam (MMSE), the mini-cog exam, as well as positron emission tomography (PET), magnetic resonance imaging (MRI) and computed tomography (CT). Further diagnostic tests may include tests of biological fluids and tissues for various biochemical markers and activities.
[0138] CK1 inhibitors may be used in the methods disclosed herein as a sole therapeutic agent, but it is contemplated herein that they may also be used in combination with or for co-administration with other active agents. For example, any one or more CK1 inhibitors may be simultaneously, sequentially, or contemporaneously administered with conventional medications proven useful for the treatment of Alzheimer's disease. These medications include cholinesterase inhibitors such as Razadyne® (formerly known as Reminyl®) (galantamine), Exelon® (rivastigmine), Aricept® (donepezil), and Cognex® (tacrine) as well as Namenda® (memantine), an N-methyl D-aspartate (NMDA) antagonist.
[0139] The inhibitory substances of the present invention can be administered as pharmaceutical compositions. Such pharmaceutical compositions for use in accordance with the present invention may be formulated in a conventional manner using one or more physiologically acceptable carriers or excipients.
[0140] Thus, the compounds and their physiologically acceptable salts and solvates may be formulated for administration by inhalation or insufflation (either through the mouth or the nose) or topical, oral, buccal, parenteral or rectal administration.
[0141] For oral administration, the pharmaceutical compositions may take the form of, for example, tablets or capsules prepared by conventional means with pharmaceutically acceptable excipients such as binding agents (e.g., pregelatinized maize starch, polyvinylpyrrolidone or hydroxypropyl methylcellulose); fillers (e.g., lactose, microcrystalline cellulose or calcium hydrogen phosphate); lubricants (e.g., magnesium stearate, talc or silica); disintegrants (e.g., potato starch or sodium starch glycolate); or wetting agents (e.g., sodium lauryl sulphate). The tablets may be coated by methods well known in the art. Liquid preparations for oral administration may take the form of, for example, solutions, syrups or suspensions, or they may be presented as a dry product for constitution with water or other suitable vehicle before use. Such liquid preparations may be prepared by conventional means with pharmaceutically acceptable additives such as suspending agents (e.g., sorbitol syrup, cellulose derivatives or hydrogenated edible fats); emulsifying agents (e.g., lecithin or acacia); non-aqueous vehicles (e.g., almond oil, oily esters, ethyl alcohol or fractionated vegetable oils); and preservatives (e.g., methyl or propyl-p-hydroxybenzoates or sorbic acid). The preparations may also contain buffer salts, flavoring, coloring and sweetening agents as appropriate.
[0142] Preparations for oral administration may be suitably formulated to give controlled release of the active compound.
[0143] For buccal administration the compositions may take the form of tablets or lozenges formulated in conventional manner.
[0144] For administration by inhalation, the compounds for use according to the present invention are conveniently delivered in the form of an aerosol spray presentation from pressurized packs or a nebulizer, with the use of a suitable propellant, e.g., dichlorodifluoromethane, trichlorofluoromethane, dichlorotetrafluoroethane, carbon dioxide or other suitable gas. In the case of a pressurized aerosol the dosage unit may be determined by providing a valve to deliver a metered amount. Capsules and cartridges of, e.g., gelatin for use in an inhaler or insufflator may be formulated containing a powder mix of the compound and a suitable powder base such as lactose or starch.
[0145] The compounds may be formulated for parenteral administration by injection, e.g., by bolus injection or continuous infusion. Formulations for injection may be presented in unit dosage form, e.g., in ampoules or in multi-dose containers, with an added preservative. The compositions may take such forms as suspensions, solutions or emulsions in oily or aqueous vehicles, and may contain formulatory agents such as suspending, stabilizing and/or dispersing agents. Alternatively, the active ingredient may be in powder form for constitution with a suitable vehicle, e.g., sterile pyrogen-free water, before use.
[0146] The compounds may also be formulated in rectal compositions such as suppositories or retention enemas, e.g., containing conventional suppository bases such as cocoa butter or other glycerides.
[0147] In addition to the formulations described previously, the compounds may also be formulated as a depot preparation. Such long acting formulations may be administered by implantation (for example subcutaneously or intramuscularly) or by intramuscular injection. Thus, for example, the compounds may be formulated with suitable polymeric or hydrophobic materials (for example, as an emulsion in an acceptable oil) or ion exchange resins, or as sparingly soluble derivatives, for example, as a sparingly soluble salt.
[0148] Pharmaceutical compositions suitable for use in the invention include compositions wherein the active ingredients are contained in an effective amount to achieve the intended purpose. The determination of an effective dose is well within the capability of those skilled in the art.
[0149] For any compound, the therapeutically effective dose can be estimated initially using either cell culture assays, e.g., of suitable cells, or animal models. The animal model may also be used to determine the appropriate concentration range and route of administration. A dose may be formulated in animal models to achieve a circulating plasma concentration range that includes the IC 50 (i.e., the concentration of the test compound that achieves a half-maximal inhibition of symptoms). Such information can then be used to determine useful doses and routes for administration in humans.
[0150] With regard to a therapeutically effective dose of a CK1 inhibitor, therapeutic efficacy and toxicity may be determined by standard pharmaceutical procedures in cell cultures or experimental animals, e.g., ED50 (the dose therapeutically effective in 50% of the population) and LD50 (the dose lethal to 50% of the population). The dose ratio between toxic and therapeutic effects is the therapeutic index, and it can be expressed as the ratio, LD50/ED50. Pharmaceutical compositions that exhibit large therapeutic indices are preferred. The data obtained from cell culture assays and animal studies are used in formulating a range of dosage for human use. The dosage contained in such compositions is preferably within a range of circulating concentrations that include the ED50 with little or no toxicity. The dosage varies within this range depending upon the dosage form employed, sensitivity of the patient, and the route of administration.
[0151] The exact dosage will be determined by the practitioner, in light of factors related to the subject that requires treatment. Dosage and administration are adjusted to provide sufficient levels of the active moiety or to maintain the desired effect. Factors that may be taken into account include the severity of the disease state, general health of the subject, age, weight, and gender of the subject, diet, time and frequency of administration, drug combination(s), reaction sensitivities, and tolerance/response to therapy. Long-acting pharmaceutical compositions may be administered every 3 to 4 days, every week, or once every two weeks depending on half-life and clearance rate of the particular formulation.
[0152] Dosages employed in practicing the present invention will of course vary depending, e.g. on the particular disease or condition to be treated, the particular CK1 inhibitor used, the mode of administration, and the therapy desired. CK1 inhibitors for use in the instant invention may be administered by any suitable route, including orally, parenterally, transdermally, or by inhalation, but are preferably administered orally. In general, satisfactory results, e.g. for the treatment of diseases as hereinbefore set forth, are indicated to be obtained on oral administration at dosages of the order from about 0.01 to 10.0 mg/kg (all weights are given as the equivalent of CK1 inhibitor in free form, although the inhibitor may be provided in free or pharmaceutically acceptable salt form). In larger mammals, for example humans, an indicated daily dosage for oral administration will accordingly be in the range of from about 0.75 to 750 mg, e.g., 50-500 mg, conveniently administered once, or in divided doses 2 to 4 times daily, or in sustained release form. Unit dosage forms for oral administration thus for example may comprise from about 0.2 to 250 mg, e.g. from about 0.2 or 2.0 to 50, 75, 100 or 200 mg of CK1 inhibitor, together with a pharmaceutically acceptable diluent or carrier therefor.
[0153] It is intended that the compounds of the invention encompass their stable isotopes. For example, the hydrogen atom at a certain position on the compounds of the invention may be replaced with deuterium. It is expected that the activity of compounds comprising such isotopes would be retained and/or it may have altered pharmacokinetic or pharmacodynamic properties. In addition to therapeutic use, compounds comprising such isotopes and having altered pharmacokinetic or pharmacodynamic properties would also have utility for measuring pharmacokinetics of the non-isotopic analogs.
[0154] It is also intended that the compounds of the invention encompass compounds having chemically bound radionuclide such as those selected from Carbon-11 (referred to as 11 C or C 11 ), Fluorine-18 (referred to as 18 F or F 18 ), Technetium-99m (referred to as 99 mTc or Tc 99 m), Indium-111 (referred to as 111 In or In 111 ) and Iodine-123 (referred to as 123 I or I 123 ), preferably 11 C or 18 F for use as, e.g., PET or SPECT tracer compounds. The radio-labelled compounds may be prepared, for example as follows:
[0000]
[0155] The following examples further illustrate the present invention and are not intended to limit the invention.
EXAMPLES
[0156] The compounds of the invention, in free or salt form may be made using the methods as described and exemplified herein and by methods similar thereto and by methods known in the chemical art. Such methods include, but are not limited to, those described below. In the description of the synthetic methods described herein, it is to be understood that all proposed reaction conditions, including choice of solvent, reaction atmosphere, reaction temperature, duration of the experiment and workup procedures, are chosen to be the conditions standard for that reaction, which should be readily recognized by one skilled in the art. Therefore, at times, the reaction may require to be run at elevated temperature or for a longer or shorter period of time. It is understood by one skilled in the art of organic synthesis that functionality present on various portions of the molecule must be compatible with the reagents and reactions proposed. If not commercially available, starting materials for these processes may be made by procedures, which are selected from the chemical art using techniques which are similar or analogous to the synthesis of known compounds. All references cited herein are hereby incorporated by reference in their entirety.
[0157] The synthetic methods for the compounds of the invention are illustrated below either in the generic synthetic scheme and/or in the specific Examples, which methods are claimed individually and/or collectively. The significances for the substituents are as set forth above unless otherwise indicated.
Example 1
2-(4-Fluorophenyl)-5-(4-methylpiperazin-1-yl)-3-(pyridin-4-yl)pyrazolo[1,5-a]pyrimidine
[0158]
[0159] Step (a)—(Z)-3-Chloro-3-(4-fluorophenyl)-2-(pyridin-4-yl)acrylonitrile: 3-(4-Fluorophenyl)-3-oxo-2-(pyridine-4-yl)propanenitrile (330 mg, 1.37 mmol) is added to POCl 3 (5 mL) at room temperature. The mixture is heated at 120° C. for an hour, and then cooled to room temperature. After excessive POCl 3 is removed under reduced pressure, the residue is treated with dichloromethane and ice, and then basified with 10N NaOH. The organic layer is separated, dried over sodium sulfate and concentrated. The obtained crude product is purified by silica-gel flash chromatography to give 200 mg of (Z)-3-chloro-3-(4-fluorophenyl)-2-(pyridin-4-yl)acrylonitrile as a brown oil (57% yield). MS (ESI) m/z 259.1 [M+H] + .
[0160] Step (b)—3-(4-Fluorophenyl)-4-(pyridin-4-yl)-1H-pyrazol-5-amine: To a solution of (Z)-3-chloro-3-(4-fluorophenyl)-2-(pyridin-4-yl)acrylonitrile (190 mg, 0.74 mmol) in ethanol (5 mL) is added hydrazine hydrate (0.075 mL, 1.5 mmol). The mixture is heated at 100° C. overnight, and then cooled to room temperature. Solvent is removed under reduced pressure to give crude 3-(4-fluorophenyl)-4-(pyridin-4-yl)-1H-pyrazol-5-amine as a redish solid, which is used directly in next step without further purification. MS (ESI) m/z 255.1 [M+H] + .
[0161] Step (c)—2-(4-Fluorophenyl)-3-(pyridin-4-yl)pyrazolo[1,5-a]pyrimidin-5(4H)-one: To a solution of 3-(4-fluorophenyl)-4-(pyridin-4-yl)-1H-pyrazol-5-amine (61 mg, 0.24 mmol) in DMF (4 mL) is added (E)-ethyl 3-ethoxyacrylate (0.053 mL, 0.37 mmol), followed by K 2 CO 3 (47 mg, 0.24 mmol). The mixture is heated at 110° C. for 9 h, and then cooled to room temperature. After filtration, the filtrate is concentrated under reduced pressure. The residue is purified by column chromatography to yield 50 mg of 2-(4-fluorophenyl)-3-(pyridin-4-yl)pyrazolo[1,5-a]pyrimidin-5(4H)-one as a brown solid (68% yield). MS (ESI) m/z 307.1 [M+H] + .
[0162] Step (d)—2-(4-Fluorophenyl)-5-(4-methylpiperazin-1-yl)-3-(pyridin-4-yl)pyrazolo[1,5-a]pyrimidine: 2-(4-Fluorophenyl)-3-(pyridin-4-yl)pyrazolo[1,5-a]pyrimidin-5(4H)-one (15 mg, 0.05 mmol) and K 2 CO 3 (20.6 mg, 0.15 mmol) are suspended in DMF (1.0 mL), and then N-phenyl-bis(trifluoromethanesulfonimide) (35.8 mg, 0.1 mmol) is added. The reaction mixture is stirred at room temperature overnight. 1-methylpiperazine 0.5 mL is added and the mixture is stirred for additional 2 h. After the solvent is removed, the obtained residue is purified by preparative TLC to give 5 mg of 2-(4-fluorophenyl)-5-(4-methylpiperazin-1-yl)-3-(pyridin-4-yl)pyrazolo[1,5-a]pyrimidine as a brown solid (26% yield). MS (ESI) m/z 389.2 [M+H] + .
Example 2
(E)-N-((1H-benzo[d]imidazol-2-ylamino)(amino)methylene)-2-(pyridin-3-yl)acetamide
[0163]
[0164] Step (a) 1-(1H-benzo[d]imidazol-2-yl)guanidine: 0-phenylenediamine (2.2 g, 20 mmol) and dicyandiamide (1.7 g, 20 mmol) are added into 4 mL of conc.HCl. The mixture is heated to reflux with vigorous stirring. After an hour of reflux, the mixture is cooled to room temperature, and then 10N NaOH (5 mL) is added carefully with temperature controlled below 30° C. The resulting precipitate is filtered and dried under vacuum to give 2.5 g of crude product as a tan powder (70% yield), which is used in next step without further purification. MS (ESI) m/z 176.1 [M+H] + .
[0165] Step (b) (E)-N-((1H-benzo[d]imidazol-2-ylamino)(amino)methylene)-2-(pyridin-3-yl)acetamide: 1-(1H-Benzo[d]imidazol-2-yl)guanidine (175 mg, 1.0 mmol), 2-(pyridin-3-yl)acetic acid (165 mg, 1.2 mmol), diisopropylethylamine (222 μL, 1.3 mmol), and O-(Benzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium tetrafluoroborate (TBTU, 385 mg, 1.2 mmol) are added in sequence into 2 mL of DMF. The mixture is stirred at room temperature overnight. The mixture is treated with water (1 mL), and then extracted with dichloromethane three times (3×3 mL). The combined organic phase is dried over sodium sulfate, and then concentrated under reduced pressure. The obtained residue is purified by preparative TLC, followed by HPLC purification to give the final product as a pale yellow powder. MS (ESI) m/z 295.1 [M+H] + .
Example 3
(E)-N-((1H-benzo[d]imidazol-2-ylamino)(amino)methylene)-2-(naphthalen-1-yl)acetamide
[0166]
[0167] The title compound is prepared using a method analogous to that for Example 2 except that 2-(naphthalen-1-yl)acetic acid is added in step (b) instead of 2-(pyridin-3-yl)acetic acid. MS (ESI) m/z 344.1 [M+H] + .
Example 4
(E)-N-((1H-benzo[d]imidazol-2-ylamino)(amino)methylene)-2-(pyridin-4-yl)acetamide
[0168]
[0169] The title compound is prepared using a method analogous to that for Example 2 except that 2-(pyridin-4-yl)acetic acid is added in step (b) instead of 2-(pyridin-3-yl)acetic acid. MS (ESI) m/z 295.1 [M+H] + .
Example 5
2-(4-acetamidophenyl)-N-(6-tert-butylbenzo[d]thiazol-2-yl)acetamide
[0170]
[0171] Step (a) 2-(4-Acetamidophenyl)acetyl isothiocyanate. 2-(4-Acetamidophenyl)acetic acid (1.34 g, 6.9 mmol) is dissolved in 20 mL CH 3 CN and triphosgene (0.69 g, 0.33 mmol) is added under stirring. 6 drops of DMF is added slowly and the mixture is then heated to 60° C. for 1.0 h. After cooling to room temperature, Ammonium isocyanate (1.05 g, 13.8 mmol) is added, and the mixture is stirred over night at room temperature. The crude 2-(4-acetamidophenyl)acetyl isothiocyanate is used directly without any further purification.
[0172] Step (b) 2-(4-acetamidophenyl)-N-(4-tert-butylphenylcarbamothioyl)-acetamide. 4-Tert-butylbenzenamine (149 mg, 1.0 mmol) is dissolved in 1.0 mL CH 3 CN and crude 2-(4-acetamidophenyl)acetyl isothiocyanate, which is prepared as above (3 mL, 1.0 mmol) is dropped in and the yellow mixture is stirred at room temperature. 1.0 h later, the mixture is concentrated and residue is purified by silica gel column chromatography (ethyl acetate: hexanes=1:1) to give product as yellow solid (100 mg, 26% yield). MS (ESI) m/z 384.2 [M+H] + .
[0173] Step (c) 2-(4-acetamidophenyl)-N-(6-tert-butylbenzo[d]thiazol-2-yl)acetamide. 2-(4-Acetamidophenyl)-N-(4-tert-butylphenylcarbamothioyl)acetamide (38 mg, 0.1 mmol) is dissolved into 1.0 mL CH 3 SO 3 H and 0.2 mL glacial CH 3 COOH at room temperature. Under stirring, 3 drops of bromine is added carefully. The red mixture is stirred vigorously for 1.0 h at room temperature and then poured onto ice to quench the reaction. The mixture is extracted with dichloromethane and the organic solution is dried and concentrated. The obtained residue is purified by preparative TLC (ethyl acetate:hexanes=2:1), followed by HPLC purification to give final product as light yellow powder (14 mg, 36% yield). MS (ESI) m/z 382.1 [M+H] + .
Example 6
2-(4-bromophenyl)-N-(6-methylbenzo[d]thiazol-2-yl)acetamide
[0174]
[0175] The title compound is prepared using a method analogous to that for Example 5 except that 2-(4-bromophenyl)acetic acid is used in step (a) instead of 2-(4-acetamidophenyl)acetic acid, and p-toluidine is used instead of 4-tert-butylbenzenamine in step (b). MS (ESI) m/z 361.1 [M+H] + .
Example 7
2-(4-hydroxyphenyl)-N-(6-methylbenzo[d]thiazol-2-yl)acetamide
[0176]
[0177] The title compound is prepared using a method analogous to that for Example 5 except that 2-(4-hydroxyphenyl)acetic acid is used in step (a) instead of 2-(4-acetamidophenyl)acetic acid, and p-toluidine instead of 4-tert-butylbenzenamine in step (b). MS (ESI) m/z 299.1 [M+H] + .
Example 8
2-(4-(dimethylamino)phenyl)-N-(6-methylbenzo[d]thiazol-2-yl)acetamide
[0178]
[0179] The title compound is prepared using a method analogous to that for Example 5 except that 2-(4-(dimethylamino)phenyl)acetic acid is used in step (a) instead of 2-(4-acetamidophenyl)acetic acid, and p-toluidine instead of 4-tert-butylbenzenamine in step (b). MS (ESI) m/z 326.1 [M+H] + .
Example 9
2-(4-acetamidophenyl)-N-(6-ethylbenzo[d]thiazol-2-yl)acetamide
[0180]
[0181] The title compound is prepared using a method analogous to that for Example 5 except that 4-ethylbenzenamine is used instead of 4-tert-butylbenzenamine in step (b). MS (ESI) m/z 354.1 [M+H] + .
Example 10
2-(4-acetamidophenyl)-N-(6-acetylbenzo[d]thiazol-2-yl)acetamide
[0182]
[0183] The title compound is prepared using a method analogous to that for Example 5 except that 1-(4-aminophenyl)ethanone is used instead of 4-tert-butylbenzenamine in step (b). MS (ESI) m/z 368.1 [M+H] + .
Example 11
N-(7-ethynylbenzo[d]thiazol-2-yl)-2-phenylacetamide
[0184]
[0185] The title compound is prepared using a method analogous to that for Example 5 except that starts with 2-phenylacetic acid in step (a) instead of 2-(4-acetamidophenyl)acetic acid, and 3-ethynylbenzenamine instead of 4-tert-butylbenzenamine in step (b). MS (ESI) m/z 293.1 [M+H] + .
Example 12
(S)-2-hydroxy-N-(6-methylbenzo[d]thiazol-2-yl)-2-phenylacetamide
[0186]
[0187] The title compound is prepared using a method analogous to that for Example 5 except that starts with (S)-2-hydroxy-2-phenylacetic acid in step (a) instead of 2-(4-acetamidophenyl)acetic acid, and p-toluidine instead of 4-tert-butylbenzenamine in step (b). MS (ESI) m/z 299.1 [M+H] + .
Example 13
(R)-2-amino-N-(6-methylbenzo[d]thiazol-2-yl)-2-phenylacetamide
[0188]
[0189] The title compound is prepared using a method analogous to that for Example 5 except that starts with (R)-2-amino-2-phenylacetic acid in step (a) instead of 2-(4-acetamidophenyl)acetic acid, and p-toluidine instead of 4-tert-butylbenzenamine in step (b). MS (ESI) m/z 298.1 [M+H] + .
Example 14
[0190] The kinase inhibition assays are conducted by using γ- 33 P-ATP as the radioligand. The targeted kinase is the human CK1δ. The Km for ATP and CK1δ is determined as 70-77 μM at Millipore. The concentration of ATP used in the assays is within 15 μM of the apparent Km for ATP. All experiments are performed as duplicates. Staurosporine is used as the internal reference inhibitor and its IC50 falls between 3.798 μM to 34.18 μM. The exemplified compounds are tested at 10 μM during the initial screening and 1 μM during the confirmation assays. The IC50 value may be converted to Ki values by using methods known to one skilled in the art, such as the Cheng-Prusoff Equation disclosed in Hsien C. Cheng, Journal of Pharmacological and Toxicological Methods (2002) 46:61-71, the contents of which are incorporated by reference in their entirety.
Example 15
[0191] In a final reaction volume of 25 μl, CK1δ (5-10 mU) is incubated with 8 mM MOPS pH 7.0, 0.2 mM EDTA, 200 μM KRRRALS(p)VASLPGL, 10 mM MgAcetate and [γ-33P-ATP] (specific activity approx. 500 cpm/pmol, concentration as required). The reaction is initiated by the addition of the ATP/Mg mix. After incubation for 40 minutes at room temperature, the reaction is stopped by the addition of 5 μl of a 3% phosphoric acid solution. 10 μl of the reaction is then spotted onto a P30 filtermat and washed three times for 5 minutes in 75 mM phosphoric acid and once in methanol prior to drying and scintillation counting.
[0192] The compounds exemplified in formulae 1.3, 2.16 and 3.28 are tested and shown to generally inhibit CK1δ and/or CK1ε with a IC 50 of less than 15 μM, most inhibit CK1δ and/or CK1ε with a IC 50 of less than 2 μM, many less than 500 nM, as described or similarly described in Example 14 or inhibit greater than 70% of CK1δ and/or CK1ε at 10 μM as described or similarly described in Example 15. | The invention provides novel compounds, composition comprising said compounds and methods for inhibiting CK1 as well as methods of treating CK1 related disorders such as Alzheimer's disease comprising administering a therapeutically effective amount of a CK1 inhibitor to a patient in need thereof. | 2 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 09/915,080, filed Jul. 25, 2001, the specification of which is hereby incorporated.
BACKGROUND OF THE INVENTION
[0002] The present invention relates to barrier movement operators and, more particularly, to such operators which respond to both rolling access codes and fixed access codes.
[0003] Automatic garage door openers comprise a door or barrier moving unit such as a controlled motor and intelligent activation and safety devices. The barrier moving unit is typically activated in response to an access code transmitted from a remote transmitter. RF signaling is the most common means of transmitting the access codes. It is important that the access code format transmitted by the remote transmitter is the same format as that expected by the receiver of the actuation equipment. A standard access code may, for example, comprise 20 digits which remain unchanged until the door opening equipment is reprogrammed. A possible security problem exists with fixed codes, since a potential thief might intercept and record a standard fixed access code. Later, the thief could return with a transmitter for producing an identical duplicate of the recorded code and open the barrier without permission. Some garage door opening systems have begun using codes to activate the system which change after each transmission. Such varying codes, called rolling codes, are created by the transmitter and acted on by the receiver, both of which operate in accordance with the same method to predict a next access code to be sent and received.
[0004] A modem barrier movement controller, such as a garage door opener, may respond to multiple different types of transmitters or wall controls. For example, such a system may respond to a portable rolling code transmitter as might be carried in an automobile, a fixed wall control which is wired to a barrier controller and to an external keypad transmitter which is attached outside the area to be closed by a movable barrier. Such a keypad transmitter can be accessed by the general public and accordingly, should provide good protection against improper use. One such keypad is described in U.S. Pat. No. 5,872,513 issued Feb. 16, 1999 to the Chamberlain Group, Inc. The keypad transmitter described in U.S. Pat. No. 5,872,514 uses a rolling code format which incorporates digits entered by user interaction with a keypad into the transmitted rolling code. A receiver of the barrier movement controller then properly validates the rolling code which may include the keypad digits and performs requested barrier operations.
[0005] The keypad type transmitter requires that a user type in a passcode then press a key to initiate the transmission of the rolling code including the typed in digits. This is a difficult task to perform when the user has his or her arms full of items, such as groceries, but wants to gain access to the closed area. What is need is a secure transmitter which permits hands free operation to send enabling security codes to the controller of a barrier movement operator.
SUMMARY OF THE INVENTION
[0006] This need is met as described and claimed herein with a keypad transmitter for mounting outside a controlled area which may respond to the voice or other biometric indicia of users by transmitting validatable codes to a controller of a barrier movement system.
[0007] In accordance with the described embodiments the keypad may be used to send a validatable code or it may be used in a learning operation of the voice responsive portion. The voice responsive portion includes speaker dependent voice analysis for some functions and speaker independent voice analysis for other functions. Before use in the speaker dependent voice analysis, the keypad/voice transmitter must learn to recognize a command of the user's choosing in the user's voice. A plurality of such commands by different users may be learned by the system.
[0008] The keypad/voice transmitter learns a command by performing voice analysis and generating a voice representation which can be stored in a memory of the transmitter. The user also enters a passcode of, for example 4 digits, to be stored in association with the stored speech representation. The passcode may be entered by user interaction with the keypad or by speaker independent voice analysis of the user-saying the passcode digits. When voice operation is activated the user speaks the command and the transmitter searches the stored speech representation for a match. When a matching (within acceptable standards for speech representations) representation is identified, the passcode associated therewith is used to form a security code which is transmitted to the controller of a barrier movement system. The controller validates the received security code and performs a requested action. When the speaker dependent voice analysis system does not recognize a spoken command, it converts to speaker independent operation to receive the spoken digits of a passcode which are then formulated into a security code which is transmitted to the barrier movement controller.
[0009] Further attributes are provided to simplify the hands free operation of the system. In one embodiment the keypad/voice transmitter includes a movable cover for the transmitter which, when the cover is closed, can be pressed by perhaps an elbow to activate voice analysis. When the cover is open a switch on the keypad/voice transmitter may be pressed to activate voice analysis. Also, embodiments are disclosed which improve the safety of the system by enabling speaker independent voice analysis response to perform a limited number of operations. For example, after a security code is transmitted from the keypad/voice transmitter speaker independent voice analysis is activated for a predetermined period of time to respond to any speaker saying one of a limited number of words or phrases to modify door movement (or non-movement) initiated by the preceding command.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] [0010]FIG. 1 is a perspective view of a garage having mounted within it a garage door operator embodying the present invention;
[0011] [0011]FIG. 2 is a block diagram of a controller mounted within the head unit of the garage door operator employed in the garage door operator shown in, FIG. 1;
[0012] [0012]FIG. 3 is a schematic diagram of the controller shown in block format in FIG. 2;
[0013] [0013]FIG. 4 shows a power supply for use with the apparatus; and
[0014] [0014]FIG. 5 is a detailed circuit description of the radio receiver used in the apparatus;
[0015] [0015]FIG. 6 is a circuit diagram of a wall switch used in the embodiment;
[0016] [0016]FIG. 7 is a circuit diagram of a rolling code transmitter;
[0017] [0017]FIG. 8 is a representation of codes transmitted by the rolling code transmitter of FIG. 7;
[0018] FIGS. 9 A- 9 b are flow diagrams of the operation of the rolling code transmitter of FIG. 7;
[0019] [0019]FIG. 10 is a circuit diagram of a keypad transmitter;
[0020] [0020]FIG. 11 is a representation of the codes transmitted by the keypad transmitter of FIG. 10;
[0021] [0021]FIG. 12 is a circuit diagram of a fixed code transmitter;
[0022] [0022]FIG. 13 is a representation of the codes transmitted by the fixed code transmitter of FIG. 12;
[0023] [0023]FIG. 14 is a flow diagram of the interrogation of the wall switch of FIG. 6;
[0024] [0024]FIG. 15 is a flow diagram of a clear radio subroutine performed by a controller of the embodiment;
[0025] [0025]FIG. 16 is a flow diagram of a set number thresholds subroutine;
[0026] [0026]FIG. 17 is a flow diagram of the beginning of radio code reception by the controller;
[0027] FIGS. 18 A- 18 C are flow diagrams of the reception of the code bites comprising full code words;
[0028] FIGS. 19 A-C are flow diagrams of a learning mode of the system;
[0029] FIGS. 20 A-B are flow diagrams regarding the interpretation of received codes;
[0030] FIGS. 21 A-B and 22 are flow diagrams of the interpretation of transmitted codes from keypad type transmitters;
[0031] [0031]FIG. 23 is a flow diagram of a test radio code subroutine used in the system of FIG. 3;
[0032] [0032]FIG. 24 is a flow diagram of a test rolling code counter subroutine;
[0033] [0033]FIG. 25 is a flow diagram of an erase radio memory subroutine;
[0034] [0034]FIGS. 26A and 26B are flow diagrams of a timer interrupt subroutine;
[0035] [0035]FIG. 27 is a flow diagram of a protector pulse received routine;
[0036] [0036]FIG. 28 is a flow diagram of routines periodically performed in the main programmed loop;
[0037] [0037]FIG. 29 is a flow diagram of portions of a travelling down routine;
[0038] [0038]FIGS. 30A and 30B illustrate a keypad/voice transmitter as used in the embodiments with an open cover and closed cover respectively;
[0039] [0039]FIGS. 31A and 31B show cutaway/sectional views of the keypad/voice transmitter to illustrate operation of a switch;
[0040] [0040]FIG. 32 is a flow diagram of a learn mode of the keypad/voice transmitter;
[0041] [0041]FIG. 33 is a flow diagram of the operational mode of the keypad/voice transmitter;
[0042] [0042]FIG. 34 is a representation of memory usage in the keypad/voice transmitter; and
[0043] [0043]FIG. 35 is a flow diagram of an additional embodiment of the keypad/voice transmitter operational mode of FIG. 33.
DETAILED DESCRIPTION
[0044] Referring now to the drawings and especially to FIG. 1, more specifically a movable barrier door operator or garage door operator is generally shown therein and referred to by numeral 10 includes a head unit 12 mounted within a garage 14 . More specifically, the head unit 12 is mounted to the ceiling of the garage 14 and includes a rail 18 extending therefrom with a releasable trolley 2 Q attached having an arm 22 extending to a multiple paneled garage door 24 positioned for movement along a pair of door rails 26 and 28 . The system includes a hand-held transmitter unit 30 adapted to send signals to an antenna 32 positioned on the head unit 12 and coupled to a receiver as will appear hereinafter. An external control pad 34 is positioned on the outside of the garage having a plurality of buttons thereon and communicates via radio frequency transmission with an antenna 32 of the head unit 12 . The external pad 34 , which is generally available to the public also includes speech analysis and speech generation capabilities. A switch module 39 is mounted on an inside wall of the garage. The switch module 39 , is connected to the head unit by a pair of wires 39 a . The switch module 39 includes a light switch 39 b , a lock switch 39 c and a command switch 39 d . An optical emitter 42 is connected via a power and signal line 44 to the head unit. An optical detector 46 is connected via a wire 48 to the head unit 12 .
[0045] As shown in FIG. 2, the garage door operator 10 , which includes the head unit 12 has a controller 70 which includes the antenna 32 . The controller 70 includes a power supply 72 (FIG. 4) which receives alternating current from an alternating current source, such as 110 volt AC, and converts the alternating current to required levels of DC voltage. The controller 70 includes a super-regenerative receiver 80 (FIG. 5) coupled via a line 82 to supply demodulated digital signals to a microcontroller 84 . The receiver 80 is energized by the power supply 72 . The microcontroller is also coupled by a bus 86 to a non-volatile memory 88 , which non-volatile memory stores user codes, and other digital data related to the operation of the control unit. An obstacle detector 90 , which comprises the emitter 42 and infrared detector 46 is coupled via an obstacle detector bus 92 to the microcontroller. The obstacle detector bus 92 includes lines 44 and 48 . The wall switch 39 (FIG. 6) is connected via the connecting wires 39 a to the microcontroller 84 . The microcontroller 84 , in response to switch closures and received codes, will send signals over a relay logic line 102 to a relay logic module 104 connected to an alternating current motor 106 having a power take-off shaft 108 coupled to the transmission 18 of the garage door operator. A tachometer 110 is coupled to the shaft 108 and provides an RPM signal on a tachometer line 112 to the microcontroller 84 ; the tachometer signal being indicative of the speed of rotation of the motor. The apparatus also includes up limit switches 93 a and down limit switches 93 b which respectively sense when the door 24 is fully open of fully closed. The limit switches are shown in FIG. 2 as a functional box 93 connected to microcontroller 84 by leads 95 . It should be mentioned that the limit switches may be replaced with an electronic passpoint system (not shown) in other embodiments.
[0046] [0046]FIG. 4 shows the power supply 72 for energizing the DC powered apparatus of FIG. 2. A transformer 130 receives alternating current on leads 132 and 134 from an external source of alternating current. The transformer steps down the voltage to 24 volts and the reduced feeds alternating current is rectified by a plurality of diodes 133 . The resulting direct current is connected to a pair of capacitors 138 and 140 which provide a filtering function. A 28 volt filtered DC potential is supplied at a line 76 . The DC potential is fed through a resistor 142 across a pair of filter capacitors 144 and 146 , which are connected to a 5 volt voltage regulator 150 , which supplies regulated 5 volt output voltage across a capacitor 152 and a Zener diode 154 to a line 74 .
[0047] The controller 70 is capable of receiving and responding to a plurality of types of code transmitters such as the multibutton rolling code transmitter 30 , single button fixed code transmitter 31 and keypad/voice type door frame mount transmitter 34 .
[0048] Referring now to FIG. 7, the rolling code transmitter 30 is shown therein and includes a battery 670 connected to three pushbutton switches 675 , 676 and 677 . When one of the pushbutton switches is pressed, a power supply at 674 is enabled which powers the remaining circuitry for the transmission of security codes. The primary control of the transmitter 30 is performed by a microcontroller 678 which is connected by a serial bus 679 to a non-volatile memory 680 . An output bus 681 connects the microcontroller to a radio frequency oscillator 682 . The microcontroller 678 produces coded signals when a button 675 , 676 or 677 is pushed causing the output of the RF oscillator 682 to be amplitude modulated to supply a radio frequency signal at an antenna 683 connected thereto. When switch 675 is closed, power is supplied through a diode 600 to a capacitor 602 to supply a 7.1 volt voltage at a lead 603 connected thereto. A light emitting diode 604 indicates that a transmitter button has been pushed and provides a voltage to a lead 605 connected thereto. The voltage at conductor 605 is applied via a conductor 675 to power microcontroller 678 which is a Zilog 125CO113 8-bit in this embodiment. The signal from switch 675 is also sent via a resistor 610 through a lead 611 to a P32 pin of the microcontroller 678 . Likewise, when a switch 676 is closed, current is fed through a diode 614 to the lead 603 also causing the crystal 608 to be energized, powering up the microcontroller at the same time that pin P 33 of the microcontroller is pulled up. Similarly, when a switch 677 is closed, power is fed through a diode 619 to the crystal 608 as well as pull up voltage being provided through a resistor 620 to the pin P 31 .
[0049] The microcontroller 678 is coupled via the serial bus 679 to a chip select port, a clock port and a DI port to which and from which serial data may be written and read and to which addresses may be applied. As will be seen hereinafter in the operation of the microcontroller, the microcontroller 678 produces output signals at the lead 681 , which are supplied to a resistor 625 which is coupled to a voltage dividing resistor 626 feeding signals to the lead 627 . A 30-nanohenry inductor 628 is coupled to an NPN transistor 629 at its base 620 . The transistor 629 has a collector 631 and an emitter 632 . The collector 631 is connected to the antenna 683 which, in this case, comprises a printed circuit board, loop antenna having an inductance of 25-nanohenries, comprising a portion of the tank circuit with a capacitor 633 , a variable capacitor 634 for tuning, a capacitor 635 and a capacitor 636 . A 30-nanohenry inductor 638 is coupled via a capacitor 639 to ground. The capacitor has a resistor 640 connected in parallel with it to ground. When the output from lead 681 is driven high by the microcontroller, the capacitor Q 1 is switched on causing the tank circuit to output a signal on the antenna 683 . When the capacitor is switched off, the output to the drive the tank circuit is extinguished causing the radio frequency signal at the antenna 683 also to be extinguished.
[0050] Microcontroller 678 reads a counter value from nonvolatile memory 680 and generates therefrom a 20-bit (trinary) rolling code. The 20-bit rolling code is interleaved with a 20-bit fixed code stored in the nonvolatile memory 680 to form a 40-bit (trinary) code as shown in FIG. 8. The “fixed” code portion includes 3 bits 651 , 652 and 653 (FIG. 8) which identify the type of transmitter sending the code and a function bit 654 . Since bit 654 is a trinary bit, it is used to identify which of the three switches, 675 , 676 or 677 was pushed.
[0051] Referring now to FIGS. 9A and 9B the flow chart set forth therein describes the operation of the transmitter 30 . A rolling code from nonvolatile memory is incremented by three in a step 500 , followed by the rolling code being stored for the next transmission from the transmitter when a transmitter button is pushed. The order of the binary digits in the rolling code is inverted or mirrored in a step 504 , following which in a step 506 , the most significant digit is converted to zero effectively truncating the binary rolling code. The rolling code is then changed to a trinary code having values 0, 1 and 2 and the initial trinary rolling code is set to 0. It may be appreciated that it is trinary code which is actually used to modify the radio frequency oscillator signal. The bit timing for a trinary code for a 0 is 1.5 milliseconds down time and 0.5 millisecond up time, for a 1, 1 millisecond down and 1 millisecond up and for a 2, 0.5 millisecond down and 1.5 milliseconds up. The up time is actually the active time when carrier is being generated. The down time is inactive when the carrier is cut off. The codes are assembled in two frames, each of 20 trinary bits, with the first frame being identified by a 0.5 millisecond sync bit and the second frame being identified by a 1.5 millisecond sync bit.
[0052] In a step 510 , the next highest power of 3 is subtracted from the rolling code and a test is made in a step 512 to determine if the result is equal to zero. If it is, the next most significant digit of the binary rolling code is incremented in a step 514 , following which flow is returned to the step 510 . If the result is not greater than 0, the next highest power of 3 is added to the rolling code in the step 516 . In the step 518 , another highest power of 3 is incremented and in a step 52 Q, a test is determined as to whether the rolling code is completed. If it is not, control is transferred back to step 510 . If it has, control is transferred to step 522 to clear the bit counter. In a step 524 , the blank timer is tested to determine whether it is active or not. If it is not, a test is made in a step 526 to determine whether the blank time has expired. If the blank time has not expired, control is transferred to a step 528 in which the bit counter is incremented, following which control is transferred back to the decision step 524 . If the blank time has expired as measured in decision step 526 , the blank timer is stopped in a step 530 and the bit counter is incremented in a step 532 . The bit counter is then tested for odd or even in a step 534 . If the bit counter is not even, control is transferred to a step 536 where the bit of the fixed code bit counter divided by 2 is output. If the bit counter is even, the rolling code bit counter divided by 2 is output in a step 538 . By the operation of 534 , 536 and 538 , the rolling code bits and fixed code bits are alternately transmitted. The bit counter is tested to determine whether it is set to equal to 80 in a step 540 . If it is, the blank timer is started in a step 542 . If it is not, the bit counter is tested for whether it is equal to 40 in a step 544 . If it is, the blank timer is tested and is started in a step 544 . If the bit counter is not equal to 40, control is transferred back to step 522 .
[0053] [0053]FIGS. 30A and 30B are perspective views of the exterior of the keypad/voice transmitter 34 . Transmitter 34 may be mounted outside of the garage interior and be generally available to the public. Transmitter 34 includes plurality of push buttons 701 - 713 corresponding generally to a telephone keypad and an activate button 725 . A cover 728 is pivotably attached by a pivot 777 to a housing 772 to provide weather protection for the device. An aperture 727 is present in the cover 728 to allow sounds to pass from a speaker 726 internal to the housing 772 . Similarly, an opening 776 is present in the cover 728 to allow spoken sounds to be picked up by a microphone 729 of the transmitter.
[0054] The activate button 725 is used in a manner discussed below to turn on a voice analysis capability of the keypad/voice transmitter 34 . Advantageously, button 725 is disposed on the transmitter 34 so that the position of cover 728 can control the state of the button. In FIG. 30A the push button 725 is shown mounted to a surface of the housing 772 so that as the cover 728 pivots closed, the cover contacts and controls the state of the push button. FIGS. 31A and 31B are cut away views of the interaction between cover 728 and push button 725 . When the cover is open (FIG. 30A), it is not in contact with button 725 but a user can freely press the button. The cover 728 in a normal closed state (FIG. 31A) rests against button 725 which is held in the non-pressed state by a spring 771 . When pressure is applied to the normally closed cover 728 (FIG. 31B), the cover presses on button 725 to change its state. With the disclosed configuration, the cover 728 can be in the normally closed state (FIG. 31A) and a user can change the state of the activate button 725 by a press against cover 728 . Such permits a user to activate voice analysis by an elbow on shoulder nudge against the cover.
[0055] [0055]FIG. 10 shows an electrical block diagram of a keypad/voice type rolling code transmitter 34 . Transmitter 34 includes a microprocessor 715 and non-volatile memory 717 powered by a switched battery 719 . Also included are 14 keys 710 - 713 and. 725 connected in row and column format. The battery 719 is not normally supplying power to the transmitter. When a button, e.g. 701 , is pressed, current flows through series connected resistors 714 and 716 and through the pressed switch to ground. Voltage division by resistors 714 and 716 causes the power supply 720 to be switched on, supplying power from battery 719 to microprocessor 715 , memory 717 and an RF transmitter stage 721 . Initially, microprocessor 715 enables a power on circuit 723 to cause a transistor 724 to conduct, thereby keeping the power supply 720 active. Microprocessor 715 includes a timer which disables power on circuit 723 a predetermined period of time, e.g. 10 seconds, after the last key 701 - 713 is pressed, to preserve battery life.
[0056] The row and column conductors are repeatedly sensed at input terminals of the microprocessor 715 so that microprocessor 715 can read each key pressed and store a representation thereof. A human operator presses a number of, for example, four keys followed by pressing the enter key 712 , the * key 711 or the # key 713 . When one of the keys 711 - 713 is pressed, microprocessor 715 generates a 40-bit (trinary) code which is sent via conductors 722 to transmitter stage 721 for transmission. The code is formed by microprocessor 715 , from a fixed code portion and a rolling code portion in the manner previously described with regard to transmitter 30 . The fixed code portion comprises, however, a serial number associated with the transmitter 34 and a PIN portion identifying the four keys pressed and which of the three keys 711 - 713 initiated the transmission. FIG. 11 represents the code transmitted by keypad transmitter 34 . As with prior rolling code transmission, the code consists of alternating fixed and rolling code bits (trinary). Bits 730 - 749 are the fixed code bits. Bits 730 - 739 represent the keys pressed and bits 740 - 748 represent the serial number of the unit in which bits 746 - 748 represent the type of transmitter. In some transmitters 34 no * and # keys are present. In this situation the * and # keys are respectively simulated by simultaneously pressing the 9 key and enter key or the 0 key and enter key.
[0057] Microprocessor combines general purpose computation capability with voice analysis and may, for example, be the RSC-300/364 produced by Sensory, Inc. of Santa Clara, Calif. The RSC-300/364 combines an 8-bit processor with neural-net algorithms to provide speaker-independent speech recognition, speaker-dependent speech recognition and speaker verification. The processor also supports speech synthesis and system control. The micro processor 715 is pre-trained, at the time of manufacture, to recognize spoken words in a speaker independent mode. Such words include the numeral digits 0 through 9, enter, pound, star, stop and start. As is described in detail later herein the microprocessor can be taught to recognize other words or phrases in a speaker dependent mode. For example, the unit can be taught to verify the phrase “open sesame” (or any other phrase) spoken by a particular speaker. As is' the nature of speaker dependent voice analysis, the words “open sesame” spoken by another-speaker will not be verified and accordingly will not be-used to control a door function.
[0058] In order to transmit an appropriate code in response to voice commands the transmitter must first be “taught” a voice command and a 4-digit passcode to be transmitted when a learned voice commands is detected. FIG. 34 represents a portion of the memory 717 of controller 715 which is used to store representations of learned voice commands and associated passcodes. To initiate a voice command learn sequence, a user presses a unique combination of keys on the keypad which is recognized by controller 715 as a voice command learn sequence. FIG. 32 represents a voice command learn sequence which begins with a step 1001 . In the learn mode, the processor 715 enables speaker 726 to request the user to speak the phrase to be learned in block 1003 . The phrase is then spoken by the user and received in block 1005 by the controller via microphone 726 . Controller 715 then performs speaker dependent analysis to encode the received phase in block 1007 . The controller 715 then directs the user to enter a 4-digit passcode in block 1009 . The passcode can be entered via the push button keys or by voice. Such passcode entry occurs in either block 1011 for keypad or 1013 for voice. When in the voice passcode mode, the controller 715 successively reminds the user to speak one digit of the passcode until 4 passcode digits have been accumulated. After the passcode is accumulated, either by push button or voice, the speech representation of the spoken command is stored in a memory location 1002 of a table 1006 as shown in FIG. 34 and the learned passcode is stored in direct association with the stored speech representation.
[0059] The voice analysis capability of transmitter 34 can also be used to record temporary passcodes in a manner similar to that shown in FIG. 32. Temporary passcodes require entry of the type of temporary passcode such as number of uses or time and the number of uses or length of time for which the passcode is intended to be active. The phrase representation, passcode and condition for a temporary passcode may be stored in fields 1010 , 1012 and 1014 of a temporary passcode table 1008 . Separate tables are provided for the semiperm and temporary passcodes so that the contents of the tables can be manipulated differently.
[0060] [0060]FIG. 33 is a flow diagram showing the use of speech to initiate the control of the door. The speech access operation begins at step 1021 which is started by pressing push button 725 , either directly or indirectly by pressing on cover 728 . A step 1023 is then performed to enter the speaker dependent mode of operation. While in the speaker dependent mode, a spoken command is received and encoded (step 1025 ) in the same manner that encoding occurred when commands were being learned (FIG. 32). The encoded command generated in block 1025 is then compared with the encoded command representations stored in table 1006 and 1008 (FIG. 34). The comparison is performed one at a time with the representation of the tables by steps 1027 , 1029 and 1031 . When a stored representation compares favorably with the received representation in step 1029 , the received representation is considered verified and the flow proceeds to step 1033 where the passcode stored in association with the stored representation is read from one of the tables 1006 or 1008 . The passcode read is combined with the other previously discussed security code parts (see FIG. 11) and the result is transmitted to the head unit which approves the security code or not as described elsewhere herein. Such approval results in control of the door to open, close or stop.
[0061] When a received speech representation does not compare favorably in step 1029 , sequential comparison with other stored representations is carried out until a step 1031 identifies that no more un-compared stored representations are available. Upon this occurrence, flow proceeds from block 1031 to block 1041 where an announcement is given that the command could not be verified and that a passcode should be entered. Block 1043 is next performed to switch from the speaker dependent analysis mode to the speaker independent analysis mode for the receipt of spoken passcode digits. Passcode-digits can be received from the keypad (block 1051 ) or via spoken commands analyzed in the speaker independent mode in step 1045 . If no proper passcode is received in block 1045 or block 1051 , it is identified in block 1047 and flow proceeds to an end of task 1039 . When a proper passcode is detected in step 1047 flow proceeds to block 1035 where a proper security code is constructed and transmitted to the head-end receiver.
[0062] [0062]FIG. 33 includes an optional step 1049 in which the transmitter 34 verifies that the passcode received in block 1045 or block 1051 is an approved passcode. An approved passcode being a passcode previously learned and stored in table 1006 or 1008 . This latter test provides verification of the transmitted security code before its transmission and may be used to remove the need for the head unit receiver to further verify the passcode of received messages.
[0063] [0063]FIG. 12 is a circuit description of a fixed code transmitter 31 which includes a controller 155 , a pair of switches 113 and 115 , a battery 114 and an RF transmitter stage 161 of the type discussed above. Controller 155 is a relatively simple device and maybe a combination logic circuit. Controller 155 permanently stores 19 bits (trinary) of the 20 bit fixed code (FIG. 13) to be transmitted. When a switch, e.g., 113 , is pressed, current from the battery 114 is applied via the switch 113 and a diode 117 to a 7.1 volt source 116 which powers RF transmitter stage 161 . The 7.1 volt source is also connected to ground via a LED 120 and Zener diode 121 which produces a regulated 5.1 volt source 118 . The 5.1 volt source is connected to power the controller 155 .
[0064] Closing switch 113 also applies battery voltage to series connected resistors 123 and 127 so that upon switch 113 closing, a voltage on a conductor 122 rises from substantially ground to an amount representing a logic “1”. Upon power up, controller 155 reads the logic 1 on conductor 122 and generates a 20 bit (trinary) code from the permanently stored 19 bits integral to the controller and the state of the switch 113 . Controller 155 then transmits the 20 bit code to the RF stage 161 via a resistor 159 and conductor 157 . The code is thus transmitted to receiver 80 . Controller 155 includes an internal oscillator regulated by an RC circuit 124 to control the timing of controller operations.
[0065] [0065]FIG. 13 represents the code transmitted from a fixed code transmitter such as transmitter 30 . The code comprises 20 bits in two 10 bit words with a blank period between the words. Each word is preceded by a sync bit which allows receiver synchronization and which identifies the type of code being sent. The sync bit for the first code word is active for approximately 1.0 milliseconds and the sync bit of the second word is active for approximate 3 milliseconds.
[0066] The wall switch 39 is shown in detail in FIG. 6 along with a portion of microcontroller 85 and the interrogate/sense circuitry interconnecting the two. Wall switch 39 comprises three switches 39 b - 39 d . Switch 39 d is the command switch which is connected directly between the conductors 39 a . Switch 39 b , the light switch, is connected between the conductors 39 a via a 1 microfarad capacitor 386 . Switch 39 c , the vacation or lock switch, is connected between conductors 39 a by a 22 microfarad capacitor 384 . Wall switch 39 also includes a resistor 380 and diode 392 serially connected between conductors 39 a . Microcontroller 85 interrogates the wall switch 39 approximately once every 10 milliseconds to determine whether a button 39 b - d is being pressed. FIG. 14 is a flow diagram of the interrogation. At the beginning (step 802 , FIG. 14) of each test, microcontroller 85 turns on transistor 368 b by a signal applied from pin P 35 to the base of transistor 368 a and at the same time turns a transistor 369 off from pin P 37 . Pins P 07 and P 06 are connected to read the voltage level between conductors 39 a by a conductor 385 and respective resistors 387 and 389 . If pins P 07 and P 06 are low (step 804 ) the command switch 39 d is closed (step 806 ) and a status bit is marked in RAM (step 830 ) to indicate such. Alternatively, if pins P 07 and P 06 are high, further tests (step 803 ) must be performed. First, micro-controller 85 turns transistor 368 b off and transistor 369 on. Then, after a short pause (step 810 ) to allow stay capacitance to discharge, pins P 07 and P 06 are again sensed (step 812 ). If P 07 and P 06 are low, no switches have been closed (step 814 ) and their status in RAM is so set (step 830 ). However, if after the short pause the level of conductor 385 is high, microcontroller 85 waits approximately 2 milliseconds (step 816 ) and again tests (step 818 ) the voltage level of conductor 385 . If the voltage is now low, the light switch 396 has been closed (step 820 ). This assessment can be made since 2 milliseconds is adequate time for the 1 microfarad capacitor 386 to discharge. If the input at pins P 07 and P 06 is still high at the 2 millisecond test, the controller retests (step 824 ) after an additional 16 millisecond delay (step 822 ). If the pins P 07 and P 06 are low after the 16 millisecond delay, the vacation switch 39 c was closed (step 826 ) and, alternatively, if the voltage at pins P 07 and P 06 is high, no switches were closed (step 828 ). At the completion of the wall switch test the status bits of the three switches 39 b , 39 c and 39 d are set to reflect their identified state (step 830 ).
[0067] The receiver 80 is shown in detail in FIG. 5. RF signals may be received by the controller 70 at the antenna 32 and fed to the receiver 80 . The receiver 80 includes a pair of inductors 170 and 172 and a pair of capacitors 174 and 176 that provide impedance matching between the antenna 32 and other portions of the receiver. An NPN transistor 178 is connected in common base configuration as a buffer amplifier. The RF output signal is supplied on a line 200 , coupled between the collector of the transistor 178 and a coupling capacitor 220 . The buffered radio frequency signal is fed via the coupling capacitor 222 to a tuned circuit 224 comprising a variable inductor 226 connected in parallel with a capacitor 228 . Signals from the tuned circuit 224 are fed on a line 230 to a coupling capacitor 232 which is connected to an NPN transistor 234 at its base. The collector 240 of transistor 234 is connected to a feedback capacitor 246 and a feedback resistor 248 . The emitter is also coupled to the feedback capacitor 246 and to a capacitor 250 . A choke inductor 256 provides ground potential to a pair of resistors 258 and 260 as well as a capacitor 262 . The resistor 258 is connected to the base of the transistor 234 . The resistor 260 is connected via an inductor 264 to the emitter of the transistor 234 . The output signal from the transistor is fed outward on a line 212 to an electrolytic capacitor 270 .
[0068] As shown in FIG. 5, the capacitor 270 couples the demodulated radio frequency signal from transistor 234 to a bandpass amplifier 280 to an average detector 282 . An output of the bandpass amplifier 280 is coupled to pin P 32 of a Z86233 microcontroller 85 . Similarly, an output of average detector 282 is connected to pin P 33 of the microcontroller. The microcontroller is energized by the power supply 72 and also controlled by the wall switch 39 coupled to the microcontroller by the lead 39 a.
[0069] Pin P 26 of microcontroller 85 is connected to a grounding program switch 151 which is located at the head end unit 12 . Microcontroller 85 periodically reads switch 151 to determine whether it has been pressed. As discussed later herein, switch 151 is normally pressed by an operator who wants to enter a receiver learn or programming mode to add a new transmitter to the accepted transmitter list stored in the receiver. When the operator continuously presses switch 151 for 6 seconds or more, all memory settings in the receiver are overwritten and a complete relearning of transmitter codes and the type of codes to be received is then needed. Pressing switch 151 for a momentary time after a 6+second press enters the apparatus into a mode for learning a new transmitter type which can be either rolling code type or fixed code type.
[0070] Pins P 30 and P 03 of microcontroller 85 are connected to obstacle detector 90 via conductor 92 . Obstacle detector 90 transmits a pulse on conductor 92 every 10 milliseconds when the infrared beam between sender 42 and receiver has not been broken by an obstacle. When the infrared beam is blocked, one or more pulses will be skipped by the obstacle detector 46 . Microcontroller scans the signal on conductor 92 every 1 millisecond to determine if a pulse has been received in the last 12 milliseconds. When a pulse has not been received, an obstacle is assumed and appropriate action, as discussed below, may be taken.
[0071] Microcontroller pin P 31 is connected to tachometer 110 via conductor 112 . When motor 106 is turning, pulses having a time separation proportional to motor speed are sent on conductor 112 . The pulses on conductor 112 are repeatedly scanned by microcontroller 85 to identify if the motor 106 is rotating and, if so, how fast the rotation is occurring.
[0072] The apparatus includes an up limit switch 93 a and a down limit switch 93 b which detect the maximum upward travel of door 24 and the maximum downward travel of the door. The limit switches 93 a and 93 b may be connected to the garage structure and physically detect the door travel or, as in the present embodiment, they may be connected to a mechanical linkage inside head end 12 , which arrangement moves a cog (not shown) in proportion to the actual door movement and the limit switches detect the position of the moved cog. The limit switches are normally open. When the door is at the maximum upward travel, up limit switch 93 a is closed, which closure is sensed at port P 20 of microcontroller 85 . When the door is at its maximum down position, down limit switch 93 b will close, which closure is sensed at port P 21 of the microcontroller.
[0073] The microcontroller 85 responds to signals received from the wall switch 39 , the transmitters 30 and 34 , the up and down limit switches, the obstruction detector and the RPM signal to control the motor 106 and the light 81 by means of the light and motor control relays 104 . The on or off state of light 81 is controlled by a relay 105 b , which is energized by pin P 01 of microcontroller 85 and a driver transistor 105 a. The motor 106 up windings are energized by a relay 107 b which responds to pin P 00 of microcontroller 85 via driver transistor 107 a and the down windings are energized by relay 109 b which responds to pin P 02 of microcontroller 85 via a driver transistor 109 a.
[0074] Each of the pins P 00 , P 01 and P 02 is associated with a memory mapped bit, such as a flip/flop, which can be written and read. The light can thus be turned on by writing a logical “1” in the bit associated with pin P 01 which will drive transistor 105 a on energizing relay 105 b , causing the lights to light via the contacts of relay 105 b connecting a hot AC input 135 to the light output 136 . The status of the light 81 can be determined by reading the bit associated with pin P 01 . Similar actions with regard to pins P 00 and P 02 are used to control the up and down rotation of motor 106 . It should be mentioned, however, that energizing the light relay 105 b provides hot AC to the up and down motor relays 107 b and 109 b so the light should be enabled each time a door movement is desired.
[0075] The radio decode and logic microcontroller 84 (FIG. 2) of the present embodiment can respond to both, rolling codes as, shown in FIG. 8 and fixed codes as shown in FIG. 13; however, after it has learned one type of code all permissible codes will be of the same type until the system memory is erased and the other type of code is entered and exclusively responded to. When the apparatus is first powered up or after memory control values have been erased in response to a greater than 6 second press of program button 151 , the system does not know whether, it will be trained to respond to fixed or rolling codes. Accordingly, the system enters a test mode to enable it to receive both types of access codes and determine which type of code is being received. In the test mode the apparatus periodically resets itself to receive one of rolling codes or alternatively, fixed codes, until a code of the expected type is received. A short press of switch 151 after the 6+ second press causes a learn mode to be entered. When a code is correctly received in the test mode, and the apparatus is in a learn mode, the type of expected code becomes the code type to be received and the received fixed code or fixed code portion of a received rolling code is stored in nonvolatile memory for use in matching later received codes. In the case of a received rolling code, the rolling code portion is also stored in association with the stored fixed code portion to be used in matching subsequently received rolling codes. After a rolling code has been learned by the system, only additional rolling codes can be learned until a reprogramming occurs. Similarly, after a fixed code is learned, only additional fixed codes can be received and learned until reprogramming occurs.
[0076] From time to time while receiving incoming codes, it is determined that a code being received is not proper and a clear radio subroutine (FIG. 15) is called by microcontroller 85 . A decision step 50 is first performed to determine whether the apparatus is in a test mode or a regular mode. When not in a test mode, flow proceeds to a step 62 to clear radio codes and blank timer after which the subroutine is exited. When decision step 50 identifies the test mode, steps 52 - 60 are performed to arbitrarily select the fixed code or rolling code mode and set up necessary values to seek the selected mode. In step 52 the lowest bit of a continuous timer is selected as a randomizer. The value of the lowest bit is then analyzed in a decision step 54 . When the lowest bit is a “1” the fixed test mode is selected in step 56 and the numeric thresholds needed for receiving fixed codes are stored in a step 60 before clearing the radio codes and exiting in step 62 . When decision step 54 determines that the lowest bit is a “0”, the rolling code mode is selected in step 58 followed by the storage of rolling code numeric threshold values in step 60 . Flow proceeds to step 62 when radio codes are cleared and the clear radio subroutine is exited.
[0077] The set number thresholds subroutine (step 60 of FIG. 15) is shown in more detail in FIG. 16. Initially, a step 180 is performed to identify which mode is presently selected. When the mode is determined to be a fixed code mode, steps 182 , 184 and 186 are next performed to set the sync threshold to 2 milliseconds, the number of bits per word to 10 and the decision threshold to 0.768 milliseconds. Alternatively, when step 180 determines that the rolling code mode is selected, steps 192 , 194 and 196 are performed to set the sync threshold to 1 millisecond, the number of bits per word to 20 and the decision threshold to 0.450 milliseconds. After the performance of either step 186 or 196 the subroutine returns in step 188 .
[0078] The primary received code analysis routine performed by microcontroller 85 begins at FIG. 17 in response to an interrupt generated by a rising or falling edge being received from the receiver 80 at pins P 32 and P 33 . Given the pulse width format of coded signals, the microcontroller maintains active or inactive timers to measure the duration between rising and falling edges of the detected radio signal. Initially, a step 546 is performed when a transition of radio signal is detected and a step 548 follows to capture the inactive timer and perform the clear radio routine. Next, a determination is made in step 550 of whether the transition was a rising or falling edge. When a rising edge is detected, step 552 is next performed in which the captured timer is stored followed by a return in step 554 . When a falling edge is detected in step 550 , the timer value captured in step 548 is stored (step 556 ) in the active timer. A decision step 558 is next performed to determine if this is the first portion of a new word. When the bit counter equals “0” this is a first portion in which a sync pulse is expected and the flow proceeds to step 560 .
[0079] In step 560 , the inactive timer value is measured to see if it exceeds 20 milliseconds but is less than 100 milliseconds. When the inactive timer is not in the range, step 562 is performed to clear the bit counter, the rolling code register and the fixed code register. Subsequently, a return is performed. When the inactive timer is within the range of step 560 , step 566 is performed to determine if the active timer is less than 4.5 milliseconds. When the active timer is too large, the values are cleared in step 568 followed by a return in step 582 .
[0080] When the active timer is found to be less than 4.5 milliseconds in step 566 , a sync pulse has been found, the bit counter is incremented in step 570 and a decision step 572 is performed. In decision step 572 , the active timer is compared with the sync threshold established in the set number thresholds subroutine of FIG. 16. Accordingly, decision step 572 uses a value of 2 milliseconds when a fixed code is expected and a value of 1 millisecond when a rolling code is expected. When step 572 determines that the active timer exceeds the threshold, a frame 2 flag is set in step 574 and a fixed keyless code flag is cleared in step 576 . Thereafter, a return is performed in step 582 . When the active timer is found in step 572 to be less than the sync threshold, a decision step 578 is performed to determine if two successive sync pulses have been of the same length. If not, the keyless code flag is cleared in step 576 and a return is performed in step 582 . Alternatively, when two equal successive sync pulses are detected in step 578 , the fixed keyless code flag is set in step 580 and a return is implemented in step 582 .
[0081] When the performance of step 558 identifies that the bit count is not “0”, indicating a non-sync bit, the flow proceeds to step 302 (FIG. 18A). In the sequence of steps shown in FIGS. 18 A- 18 D, microcontroller 85 identifies the individual code bits of a received code word. In step 302 the length of the active period is compared with 5.16 milliseconds and when the active period is not less, the registers and counters are cleared 5 and a return is performed. When step 302 indicates that the active period was less than 5.16 milliseconds, a step 306 is performed to determine if the inactive period is less than 5.16 milliseconds. If it is less, the step 304 is performed to clear values and return. Alternatively, when step 306 is answered in the affirmative a bit has been received and the bit counter is incremented in a step 308 . In the subsequent step 310 the value of the active and inactive timers are subtracted and the result is compared in step 312 with the complement of the decision threshold for the type of code expected. When the result is less than the complement of the decision threshold, a bit value of “0” has been received and flow continues through a step 314 to step 322 (FIG. 18B) where it is determined whether or not a rolling code is expected.
[0082] When step 312 determines that the time difference is not less than the complement of the decision threshold flow proceeds to decision block 316 (FIG. 18A) where the result is compared to the decision threshold. When the result exceeds the decision threshold, a bit having a value 2 has been received and the flow proceeds via step 318 to the decision step 322 . When decision step 316 determines that the result does not exceed the decision threshold, a bit having a value of 1 has been received and flow continues via step 320 to decision step 322 .
[0083] In step 322 , microprocessor 85 identifies if rolling codes are expected. If not, flow proceeds to step 338 (FIG. 18B) where the bit value is stored as a fixed code bit. When rolling codes are expected, flow continues from block 322 to a decision step 324 where the bit count is checked to identify whether a fixed code bit or a rolling code bit is received. When step 324 identifies a rolling code bit, flow proceeds directly to a step 340 (FIG. 18B) to determine whether this is the last bit of a word. When a fixed bit is detected in step 324 , its value is stored in a step 326 and a step 328 is performed to identify if the currently received bit is an ID bit. If the bit count identifies an ID bit, a step 330 is performed to store the ID bit and flow proceeds to the storage step 338 . When step 328 determines that the currently received bit is not an ID bit, flow continues to step 334 (FIG. 18B) to determine whether the currently received bit is a function bit. If it is a function bit, its value is stored as a function indicator in step 336 and flow continues to step 338 for storage as a fixed code bit. When step 334 indicates that the currently received bit is not a function bit, flow proceeds directly to step 338 . After the storage step 338 , flow for the fixed bit reception also proceeds to step 340 to determine whether a full word has been received. Such determination is made by comparing the bit counter with the threshold values established for the type of code expected. When less than a word has been received, flow proceeds to step 342 to await other bits.
[0084] When a full word has been received, flow proceeds to a step 344 (FIG. 18C), where the blank timer is reset. Thereafter, flow continues to decision step 346 to determine if two full words (a complete code) have been received. When two full words have not been received, flow proceeds to block 348 to await the digits of a new word. When two full words are detected in step 346 , flow proceeds to step 350 (FIG. 18C) to determine whether rolling codes are expected. When rolling codes are not expected, flow continues to step 358 . When rolling codes are expected, flow proceeds from step 350 through restoration of the rolling code in a step 352 to a decision step 354 where it is identified if the ID bits indicate a voice/keypad transmitter, e.g., transmitter 34 . When a voice/keypad transmitter code is detected, a flag is set in step 356 and flow proceeds, to a decision step 362 , discussed below. When step 354 indicates that the code is not from a voice/keypad transmitter, flow continues to the decision step 358 to identify whether a vacation flag is set in memory. The vacation flag is set in response to a human activated vacation switch and when the vacation flag is set, no radio codes are allowed to activate the door open while codes from voice/keypad transmitters such as 34 are permitted to activate the system. Accordingly, if a vacation flag is detected in step 358 , the code is rejected and a return is performed. When no vacation flag has been set, flow proceeds to a step 362 where it is determined if a receiver learn mode is set. Receiver learn modes can be set by several types of operator interaction. The program switch 151 can be pressed. Also, by preprogramming, microprocessor 85 is instructed to interpret the press and hold of the command and light buttons of the wall control 39 while energizing a code transmitter. Additionally, prior radio commands can place the system in a learn mode. The decision at step 362 is not dependent on how the learn mode is set, but merely on whether a learn mode is requested. At this point it is assumed that a learn mode has been set and flow continues to step 750 (FIG. 19A).
[0085] In step 750 , a determination is made concerning the type of code expected. When a fixed code is expected, flow proceeds to step 756 where the present fixed code is compared with the prior fixed code. When step 756 does not detect a match, the present code is stored in a past code register and a return is executed. When step 750 identifies that rolling code is expected, a step 752 is performed to determine if the present rolling code matches the past rolling code. If no match is found, flow proceeds to step 754 where the present code is stored in a past code register and a return is executed. When step 752 determines that the rolling codes match, the fixed portion of the received rolling code is compared with the past fixed portions in step 756 . When no match is detected, the code is stored in a past code register and a return is executed. When step 756 detects a match, flow proceeds to step 758 to identify if the learn was requested from the wall control 39 . If not, flow proceeds to step 766 (FIG. 19B) where the transmitter function is set to be a standard command transmitter. When step 758 determines that the learn mode was commenced from wall control 39 , flow proceeds to step 760 to determine whether fixed or rolling codes are expected. When fixed codes are expected, flow proceeds to step 766 (FIG. 19B) where the function is set to be that of standard command transmitter. When rolling codes are identified in step 760 , flow proceeds to step 762 (FIG. 19B).
[0086] In step 762 it is determined if the light and vacation switches of the wall control 39 are being held. If so, the transmitter is set to be a light switch only in step 763 and flow proceeds to step 768 . When step 762 is answered in the negative, flow proceeds to step 764 to determine if the vacation and command switches are being held. If they are, flow proceeds to step 765 to set the transmitter function as open/close/stop and flow proceeds to step 768 . When step 764 determines that the vacation and command switches are not being held, flow proceeds to step 766 where the transmitter is marked as a standard command transmitter. After step 766 , a step 768 is performed to identify if the received code is in the radio code memory. If the present code is in radio code memory, flow proceeds to step 794 (FIG. 19C). If the received code is not in radio code memory, flow proceeds from step 768 to 780 to determine whether the system is in a permanent or a test mode. When step 780 determines that the system is in a test mode, the current radio mode, either fixed or rolling, is set as a permanent mode in step 782 and flow proceeds to a step 784 to set the current thresholds by storing a pointer to the storage location in ROM into permanent memory.
[0087] After step 784 , flow proceeds to step 786 (FIG. 19B) to determine if the present code is from the keypad transmitter and specifies an input code 0000 . If so, the step 787 is executed where the received code is rejected and a return is executed while remaining in the learn mode. When the code 0000 is not present, flow continues to step 788 to find whether a non-enter key (* or #) was pressed. If so, flow proceeds to step 787 . If not, flow continues to decision step 789 (FIG. 19C) to identify if an open/close/stop transmitter is being learned. When the present learning does not involve an open/close/stop transmitter, flow proceeds to step 792 where the code is written into nonvolatile memory. When step 789 (FIG. 19C) determines that an open/close/stop transmitter is being learned, flow proceeds to step 790 to determine if a key other than the open key is being pressed. If so, flow proceeds to block 789 and if not, flow proceeds to block 792 where the fixed code is stored in nonvolatile memory. After step 792 , step 794 is performed to determine if rolling code is the present mode. If not, flow proceeds to step 799 where the light is blinked to indicate the completion of a learn and a return is executed. When step 794 identifies the mode as rolling code, flow proceeds to step 795 where the received rolling code is written into nonvolatile memory in association with the fixed code written in step 792 . After step 795 , the current transmitter function bytes are read in step 796 , modified in step 797 and stored in nonvolatile memory. Following such storage, the work light is blinked in step 799 and a return is executed.
[0088] The performance of step 799 concludes the learn function which began when step 362 (FIG. 18C) identified a learn mode. When step 362 does not identify a learn mode, flow proceeds from step 362 to step 402 (FIG. 20A). In step 402 the ID bits of the received code are interpreted to identify whether the code is from a rolling code keypad/voice type transmitter, e.g. 34. If so, flow proceeds to step 450 (FIG. 21A). When the ID bits do not indicate a rolling code keypad/voice entry, flow proceeds to a step 404 where a check is made to see if an 8 second window in which a learn mode may be set exists which was entered from a fixed code keypad transmitter. When the learn mode exists, flow proceeds to step 406 to determine if the operator has entered a special “0000” code. If the special code has been entered, flow proceeds from step 406 to step 410 where the learn mode is set and an exit performed. When step 406 does not detect the special “0000” code, flow proceeds to a step 408 , which step is also entered when no 8 second learn mode was detected in step 404 .
[0089] In step 408 the received code is compared with the codes previously stored in nonvolatile memory 88 . When no match is detected, the radio code is cleared and an exit is performed in step 412 . Alternatively, when step 408 detects a match, flow proceeds to step 414 (FIG. 20B) which identifies when rolling codes are expected. When step 414 determines that rolling codes are not expected, flow proceeds to step 428 where a radio command is executed and an exit performed. When step 414 determines that a rolling code is expected, flow proceeds to step 416 to determine if the rolling portion of the received code is within the accepted range. When the rolling portion is out of range, step 418 is performed to reject the code and exit. When the rolling code is within the range, step 420 is performed to store the received rolling code portion (rolling code counter) in nonvolatile memory and flow proceeds to a step 422 , which identifies whether the function bits of the received code identify a light control signal. When a light control signal is identified, flow proceeds to step 424 where the status of the light is changed, the radio is cleared and an exit performed. When the presently received code is not identified in step 422 as a light control, flow proceeds to step 426 to identify if the present code is an open/close/stop command. When step 426 does not identify an open/close/stop command, flow proceeds to the step 428 where a radio command is set and an exit performed.
[0090] When step 426 identifies an open/close/stop command, flow proceeds to step 430 (FIG. 20B) to interpret the command. Step 430 ′ identifies from the function bits of the received code which of the three buttons was pressed. When the open button was pressed, flow proceeds to a step 432 to identify what the present state of the door is. When the door is stopped or at a down limit, step 434 is entered where an up command is issued and exit performed. When step 432 identifies that the door is traveling down, a reverse door command is issued and an exit performed in step 436 . In the third case, when step 432 detects the door to be open, step 440 is entered and no command is issued.
[0091] When step 430 identifies that the close transmitter button was pressed, flow proceeds to step 438 to identify what state the door is in. When step 436 determines that the door is traveling up or at a down limit, the step 440 is performed where no command is issued and an exit performed. Alternatively, when step 438 identifies that the door is stopped at other than the down limit, a down command is issued in a step 442 . When step 430 determines that the stop button was pressed, flow proceeds to step 444 to identify the state of the door. When the door is already stopped, flow proceeds from step 444 to step 448 where no command is issued and an exit performed. When the door is identified in step 444 as traveling, a stop command is issued in step 446 and an exit performed.
[0092] It will be remembered that when step 402 (FIG. 20A) identifies that a rolling code keypad/voice code is received, flow proceeds to step 450 (FIG. 21A). In step 450 the serial number portion of the received code is compared with the serial numbers of those codes stored in nonvolatile memory. When no match is detected, flow proceeds to step 452 where the code is rejected and an exit performed. When step 450 detects a match, flow proceeds to step 454 to identify if the rolling code portion is within the forward window. When the code is not within the forward window, flow proceeds to the step 452 where the received code is rejected and an exit is performed.
[0093] When the received rolling code portion is found to be within the forward window in step 454 a step 456 is performed where the received code is used to update the rolling code counter in memory. This storage keeps the rolling code transmitter and rolling code receiver in synchronism. After step 456 , a step 458 is entered to identify which code reception mode has been set. When normal code reception is identified in step 458 , a step 460 (FIG. 21B) is performed to identify if the user input portion of the received code matches a stored user passcode. When a match is detected in step 460 , flow proceeds to step 470 to identify which of the keypad input keys, *, # or enter, was pressed. When step 470 identifies the enter key, a step 472 is performed in which a keypad/voice entry command is issued and an exit initiated. When the * key is detected in step 470 , flow proceeds to step 476 where the light is blinked and the learn temporary passcode flag is set to identify the learn temporary passcode mode. When step 470 identifies that the # key was pressed, flow proceeds to a step 474 to blink the light and to set a standard learn mode.
[0094] When the performance of step 460 determines that the received user input portion does not match a passcode stored in memory, flow proceeds to step 462 where the received user input portion is compared to temporary user input codes. When step 462 does not discover a match, a step 464 is performed to reject the code and exit. When step 462 identifies a match between a received user input code and a stored temporary password, flow proceeds to step 466 to identify whether the door is at the down limit. If not, flow proceeds to step 472 for the issue of a keypad/voice entry command. When step 466 identifies that the door is closed, a step 468 is performed to identify whether the previously set time or number of uses for the temporary passcode has expired. When step 468 identifies expiration, the step 464 is performed to reject the code and exit. When the temporary passcode has not expired, flow proceeds to step 478 (FIG. 21B) where the type of user temporary passcode, e.g., duration or number of activations, is checked. When step 478 identifies that the received temporary passcode is limited to a number of activations, a step 480 is executed to decrement the remaining activations and a step 472 is executed to issue an entry command. When step 478 identifies that the received keypad/voice passcode is not based on the number of activations (but instead on the passage of time) flow proceeds from step 478 to the issuance of an entry command in step 472 . No special up date is needed for timed temporary passcodes since the microcontroller 85 continuously updates the elapsed time.
[0095] It will be remembered that a step 458 (FIG. 21A) was initiated to identify the reception mode presently enabled. When the learn temporary passcode mode is detected, flow proceeds from step 458 to step 482 (FIG. 22). In step 482 a query is performed to determine the enter key was used to transmit the received code. When the enter key was not used, a step 484 is performed to reject the code and exit. When the enter key was used, a step 486 is performed to determine whether the received user input code matches a passcode already stored in memory. If so, a step 488 is performed to reject the code. When step 486 identifies no matching user passcodes, the new user input code is stored as the temporary passcode in step 490 and flow proceeds to step 492 where the light is blinked and the learn temporary passcode duration learn mode is set for subsequent use. When the learn temporary passcode duration mode is later detected in step 458 , flow proceeds to a step 481 where the user entered passcode is checked to see if it exceeds 255. This is an arbitrary limit to either 255 activations or 255 hours of temporary access. When the user entered code exceeds 255 it is rejected in step 483 . When the user entered code is less than 255, a step 485 is performed to identify which key was used to transmit the keypad/voice code. When the * key was used, the transmitted code is to indicate a time duration for the temporary password the time duration mode is set in step 487 and a time is started in step 491 using the code as the number of hours in the temporary code duration. When step 485 determines that the # key was used to transmit the code, a flag is set in step 489 indicating that the temporary mode is based on the number of activations and the number of activations is recorded in step 491 . After step 491 , the light is blinked and an exit is performed.
[0096] [0096]FIG. 23 is a flow diagram of a radio code match subroutine. The flow begins at a step 862 where it is determined whether a rolling code is expected or not. When a rolling code is not expected, flow proceeds to a step 866 where a pointer identifies the first radio code stored in nonvolatile memory. When step 866 determines that a rolling code is expected, all transmitter type codes are fetched in a step 864 before beginning the pointer step 866 . After step 866 , a decision step 868 is performed to determine whether an open/close/stop transmitter is being learned. If so, a step 870 is performed in which the memory code is subtracted from the received code and the flow proceeds to a step 878 to evaluate the result. From step 878 the flow proceeds to a step 878 to evaluate the result. From step 878 , the flow proceeds to a step 880 to return the address of the match when the result of the subtraction is less than or equal to two. When the result of the subtraction is not less than or equal to two, the flow continues from step 878 to step 882 to determine if the last memory location is being compared. If the last memory was compared, step 884 is performed to return a “no match.”
[0097] When step 868 indicates that the system is not learning an open/close/stop transmitter, flow continues to step 872 to determine if the memory code is an open/close/stop code. If it is, flow proceeds through steps to step 874 where the received code is subtracted from the memory code. Thereafter, flow proceeds through step 878 to either step 880 or 882 as above described. When step 872 determines that the current memory code is not an open/close/stop code, flow proceeds to step 876 . In step 876 the received code is compared with the code from memory and, if they match, step 880 is performed to return the address of the matching code. When step 876 determines that the compared codes do not match, flow continues to step 882 to determine if the last memory location has been accessed. When the last memory location is not being accessed, the pointer is adjusted to identify the next memory location and the flow returns to step 868 using the contents of the new location. The process continues until a match is found or the last memory location is detected in step 882 .
[0098] [0098]FIG. 24 is a flow diagram of a test rolling code counter subroutine which begins at a step 888 in which the stored rolling code counter is subtracted from the received rolling code and the result is analyzed in a step 890 . When step 890 determines that the subtraction result is less than “0”, flow continues to step 892 where the subroutine returns a backward window lockout. When step 890 determines that the subtraction result is greater than 0 and less than 1000, the subroutine returns a forward window indication in step 892 .
[0099] [0099]FIG. 25 is a flow diagram of an erase radio memory routine which begins at a step 686 of clearing all radio codes, including keyless temporary codes. Next, a step 688 is performed to set the radio mode in nonvolatile memory as testing for rolling codes or testing for fixed codes. Step 690 is next performed in which the working radio mode is set as fixed code test and the fixed code number thresholds are set in a step 692 . A return step 694 completes the subroutine.
[0100] [0100]FIG. 26 shows a timer interrupt subroutine which begins at a step 902 when all software times are updated. Next, flow proceeds to a step 904 to determine whether a 12 millisecond timer has expired. The 12 millisecond timer is used to assure that obstructions which block the light beam in protector 90 and cause the absence of a 10 millisecond obstructive pulse, are rapidly detected. When the 12 millisecond timer has not expired, flow proceeds to a step 914 discussed below. Alternatively, when the timer expires, a step 906 is performed to determine if a break flag, which is set at the first missed pulse, is set. If it is not set, flow proceeds to step 910 in which the break flag is set. If the break flag was detected in step 906 , flow continues to step 908 in which an IR block flag, indicative of a plurality of missed 10 millisecond obstruction pulses, is set. Flow then proceeds through step 910 to step 912 where the 12 millisecond timer is reset. Decision step 914 , which is performed after step 912 , determines whether it has been more than 500 milliseconds since a valid radio code has been received. If more than 500 milliseconds has transpired, step 916 is performed to clear a radio currently on air flag and an exit is performed. When step 914 determines that 500 milliseconds has not expired, flow proceeds directly to exit step 918 .
[0101] [0101]FIG. 27 is a flow diagram of an IR pulse received interrupt begun whenever a protection pulse is received by microcontroller 85 . Initially, a step 920 is performed in which the IR break flag is reset and the flow proceeds to step 922 where the IR block flag is reset. This routine ends by resetting the 12 millisecond timer in step 924 and exiting in step 926 .
[0102] The control structure of the present embodiment includes a main loop which is substantially continuously executed. FIG. 28 is a flow diagram showing portions of the loop. Every 15 seconds a step 928 is performed in which the local radio mode is loaded from nonvolatile memory and the number thresholds are set in a step 930 . This activity ends with a return step 946 . Every hour a step 932 is performed to determine if a keypad temporary timer is currently active. If so, flow proceeds to step. 914 where the time is decremented and a return is executed at step 946 .
[0103] Every 1 millisecond a step 936 is performed to determine if the IR break flag is set and the IR block flag is not set. This condition is indicative of the first missed protector pulse. If the determination in step 936 is negative, a return is performed. If step 936 detects only the IR break flag and not the IR block flag, a step 938 is performed to identify if the door is at the up limit. When the door is not at the up limit, a return is performed. When step 938 detects the door at the up limit, a step 940 is performed to identify if the light is on. If the light is on, it is blinked a predetermined number of times in step 942 and a return is executed. When step 940 determines that the light is off a step 944 is performed to turn the light on and set a 4.5 minute light keep on timer. A return is executed after step 944 .
[0104] [0104]FIG. 29 is a flow diagram illustrating the use of the IR protection circuit in door control. At a step 948 a decision is made whether a memory matching keypad type transmitter is on the air. If so, flow proceeds to step 956 to determine if the down limit of door travel has occurred. If the down limit has been reached, a step 958 is performed to set a stopped at down limit state of the door. When step 956 determines that the down limit has not been reached, a step 960 is performed to continue the downward travel of the door. When step 948 is answered in the negative, a step 950 is performed to determine if the command switch is being held down. If it is, flow proceeds to step 956 and either step 958 or 960 as discussed above. When step 950 is answered in the negative, a step 952 is performed in which the IR break flag is checked. If the break flag is set, signalling an obstruction, a step 954 is performed to reverse the door, set the new state of the door and set an obstruction flag. When step 952 does not detect an IR break flag, flow proceeds to step 956 as above described. It should be mentioned that the conditions established in steps 948 and 950 are intended to allow the operator to override the obstruction detector.
[0105] In the preceding embodiments the keypad/voice transmitter 34 , under conditions discussed above, transmits a security code to the head end receiver to initiate door movement. It may be found desirous to have a somewhat less secure arrangement to control door movement for a short period of time after door movement is initiated. FIG. 34 represents an additional function which is enabled to control a moving door for a period of, for example, 20 seconds after a security code is transmitted from the keypad/voice transmitter 34 . It is intended that the capability of FIG. 34 would be provided between steps 1037 and 1039 of the FIG. 33 flow diagram.
[0106] In step 1037 (FIG. 34) a security code is transmitted to which the head unit will respond by moving the door. Next a step 1051 is performed to enter the speaker independent analysis mode. A decision block 1053 is then performed to identify if the word “stop” has been received. If the word “stop” is not received, a, loop is continued which will be terminated after 20 seconds by a step 1055 . When step 1055 identifies the passage of 20 seconds after the transmission of a security code (block 1037 ), a step 1057 is performed to disable speaker independent analysis and the process ends at block 1039 . If the word “stop” by any speaker is detected in step 1053 flow proceeds to step 1059 where a security code to which the head end will respond by stopping or causing the door to raise, is transmitted. The transmitted security code may conveniently be the same security code transmitted in block 1037 with one rolling code iteration. The functions and apparatus represented by FIG. 34 allow, for a brief period, any speaker to change door movement by saying the word “stop”. The preceding capability specifically empowers a user to stop a moving door by speaker independent voice analysis. The transmitter may also be taught to respond to other speaker independent words or phrases to initiate or stop other barrier movement in the interval of time after transmission of a security code.
[0107] While there has been illustrated and described a particular embodiment of the present invention, it will be appreciated that numerous changes and modifications will occur to those skilled in the art, and it is intended in the appended claims to cover all those changes and modifications which fall within the true spirit and scope of the present invention. By way of example, the transmitter and receivers of the disclosed embodiment are controlled by programmed microcontrollers. The controllers could be implemented as application specific integrated circuits within the scope of the present invention. | A keypad transmitter for mounting outside a controlled area which may respond to the voice or other biometric indicia of users by transmitting validatable codes to a controller of a barrier movement system. The keypad may be used to send a validatable code or it may be used in a learning operation of the voice responsive portion. The voice responsive portion includes speaker dependent voice analysis for some functions and speaker independent voice analysis for other functions. | 4 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This present invention relates to solid bleach activator compositions and methods for use and preparation thereof More particularly, the invention pertains to activator compositions that include tetra acetyl ethylene diamine (TAED) and a phosphate salt capable of forming peracetic acid with the hydrogen peroxide component of bleach. Preferably, solid activator and bleach-containing bodies are diluted in separate containers before simultaneous addition to a detergent solution. The solid activator composition may be used in detergent/bleaching agent systems for warewashing, laundry, or general hard surface cleaning.
2. Description of the Prior Art
Oxygen-based bleaching agents have been widely used as an adjunct to detergents for household and industrial dishwashing, laundering, and general hard surface cleaning applications, because of the improved cleaning results that are directly attributable to the bleaching composition. However, in order for the oxygen-based bleaching composition to be effective, it is necessary that the washing temperature be greater than 140° F. At lower temperatures, oxygen-based bleaches, such as the perborates and percarbonates, are in-effective.
It has been well documented that tetra acetyl ethylene diamine (TAED) activates the peroxide carriers of oxygen-based bleaches and provides effective bleaching of stains at temperatures below 140° F. for which the oxygen-based bleaches alone are ineffective. Furthermore, it has been documented that TAED-activated formulations kill bacteria and other microorganisms even at these lower temperatures. However, prior TAED formulations have been in liquid form and are consequently difficult to use with many types of dishwashing and other equipment which typically employ solid cleansing products.
There is accordingly a need in the art, particularly in the industrial laundering area, for substantially homogeneous solid oxygen bleach activator-containing compositions which will readily dissolve in warm or hot water, and provide activation for oxygen-based bleaches at temperatures below 140° F. Furthermore, the solid activator composition should improve the bleaching of stains and demonstrate a significant antimicrobial effect.
SUMMARY OF THE INVENTION
The present invention overcomes the problems outlined above, and provides a solid bleach activator comprising a solid, self-sustaining, monolithic body having therein respective quantities of tetra acetyl ethylene diamine, phosphate sequestering agent and non-phosphate solidifying agent, such ingredients being intimately mixed and formed into a solid body. Preferably, the activator bodies include from about 2-20% by weight tetra acetyl ethylene diamine, from about 20-60% by weight phosphate sequestering agent, from about 2-25% by weight non-phosphate solidifying agent, and from about 10-50% by weight water. The activator compositions of the invention are also normally formulated with effective levels of organic surfactant and other functional ingredients. The solid activator compositions typically have a specific gravity of from about 0.8 to 1.7, and more preferably from about 1.0 to 1.4. Likewise, such solid bodies normally have a hardness such that they melt at temperatures greater than 130° F. In use, the solid activators are subjected to hot water under pressure so as to produce an aqueous activator dispersion which can be combined with a dilute aqueous oxygen-based bleach in a detergent system so as to activate the bleach even at relatively low temperatures.
The solid activator bodies of the invention are advantageously used in conjunction with a solid self-sustaining monolithic body containing a quantity of peroxyhydrate salt bleach. The bleach-containing and activator bodies are then subjected to corresponding quantities of hot water (usually from about 110°-140° F.) for dispersion thereof, thereby producing a bleaching dispersion and an activator dispersion. Such dispersions are then introduced, either simultaneously or seriatim, into the cleaning chamber of equipment such as an industrial dishwasher along with a liquid washing and/or cleaning dispersion. Normally, equipment of this type includes first and second bowls equipped with spray heads; the bleach-containing and activator bodies are placed within a respective bowl and are subjected to hot, pressurized water for creation of the corresponding dispersions. Such dispersions are then introduced via conduits leading to the equipment cleaning chamber.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a schematic representation of the preferred washing and/or cleaning equipment designed to use the solid activator bodies of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In preparing the solid activator bodies of the invention, a quantity of tetra acetyl ethylene diamine (TAED) is first mixed with an amount of water. Desirably, TAED comprises from about 2-20% by weight of the final solid body while water makes up from about 10-50% by weight thereof. This initial formulation is then combined with a sequestering agent such as one or more phosphate salts in amounts of from about 20-60% by weight of the solid body, together with from about 2-25% by weight of non-phosphate solidifying agent. Other optional ingredients such as organic surfactants, dispersing agents, and fluorescent whitening agents may be added. The resultant slurry is then poured into a suitable mold for cooling into a solid body.
The preferred phosphate sequestering agent or salt fraction is a mixture of from about 25-75% by weight of tetrasodium pyrophosphate (more preferably from about 40-60% by weight) and from about 75-25% by weight of pentasodium tripolyphosphate (more preferably from about 65-35% by weight), based upon the total weight of the sequestering agent salt fraction taken at 100% by weight. Sodium hexametaphosphate may be used in place of a portion of the tetrasodium pyrophosphate in amounts up to 10% by weight, based upon the total weight of the sequestering agent. In addition, tetrapotassium pyrophosphate may be substituted for tetrasodium pyrophosphate for faster water solubility in amounts of from about 12.5-37.5% by weight of the sequestering agent salt fraction. While the primary function of the phosphates is to serve as a hard water ion sequesterant to facilitate dispersion of the activator bodies in water, the phosphates also simultaneously may serve as water-absorbing solidifying agents.
A wide variety of non-phosphate solidifying agents can be used in the solid compositions of the invention. The most commonly employed solidifiers are sodium sulfate or sodium chloride and mixtures thereof. The non-phosphate solidifying agent is preferably used at a level of from about 4-20% by weight.
When the solid activator composition is designed to be used with a warewashing or laundry detergent, it is preferably formulated to contain effective amounts of synthetic organic surfactants. The surfactants should be chosen so as to be stable and chemically compatible in the presence of hydrogen peroxide. One class of useful surfactants are the anionic surfactants. Preferred anionic surfactants include alkali metal alkylbenzene sulfonates, alkali metal alkyl ether sulfates, alkali metal alkyl sulfates, alkali metal alpha olefin sulfonates, alkali alkane sulfonates, and mixtures thereof.
Nonionic surfactants may be employed either alone or in combination with the anionic surfactants. This class of synthetic detergents may be broadly defined as compounds produced by the condensation of alkylene oxide groups with an organic hydrophobic compound that may be aliphatic or aromatic in nature. Preferred nonionic surfactants include polyethylene oxide condensates of alkylphenols, polyethylene oxide condensates of primary or secondary alcohols, polyoxyethylene condensates of a hydrophobic polypropyleneoxide/propylene glycol condensate, alkyl polyglucosides, and alkyl amine oxides.
The amount of organic surfactants added to the activator composition varies depending on the intended use of the composition. For example, an effective activator composition can be prepared containing from about 0.5-15% by weight of the surfactant agent.
Dispersing agents, such as sodium polyacrylates, citric acid, ethylenediaminetetraacetic acid (EDTA) or nitrilotriacetic acid (NTA), can also be added to the activator composition. The preferred dispersing agent is sodium polyacrylate because of its effectiveness in the presence of phosphate salts. Furthermore, fluorescent whitening agents can be added so long as they are compatible with oxygen-based bleaches.
A preferred activator composition is prepared as follows, using the ingredients of Table 1.
TABLE 1______________________________________Constituent % by weight______________________________________Water 30.0Sodium polyacrylate (Colloid 207, 45-50%) 5.0Tetra acetyl ethylene diamine (TAED) 8.0Tetrasodium pyrophosphate 18.0Sodium sulfate 11.8Sodium alkylbenzene sulfonate (90%) 3.0Tinopal CBS (Fluorescent whitening agent) 0.2Pentasodium tripolyphosphate 22.0Polyglucoside 625 FE nonionic surfactant 2.0______________________________________
In preparing a solid activator body using the above ingredients, 150 grams of tap water was placed in a mixer and agitation was commenced. Then 25 grams of Colloid 207 was added, followed by 40 grams of TAED. When these ingredients were evenly dispersed in the mixer, 90 grams of tetrasodium pyrophosphate and 59 grams of sodium sulfate were added and agitation was continued until dissolution was nearly complete. Then 15 grams of the sodium alkylbenzene sulfonate and 1 gram Tinopal CBS were added with continued agitation. One hundred ten grams of pentasodium tripolyphosphate were next added, and as soon as an even dispersion was attained 10 grams of the Polyglucoside 625 FE nonionic surfactant were added. When the completed slurry showed signs of a viscosity increase upon further mixing, the slurry was poured into capsules and allowed to cool and harden for 24 hours. At this point the solid activator body was ready for use. In one commercial embodiment, the finished activator body weighs approximately 7 pounds.
When the activators of the invention are used in combination with oxygen-based bleach in detergent systems, peracetic acid is formed in situ in the cleaning or laundry equipment. Peracetic acid is a very powerful antimicrobial, and therefore the activators hereof can be used, e.g., to control potential avenues of infection through the wash water effluent from laundries in hospitals and nursing homes. In one comparative test, the bacteriological contamination of laundry wash water from the garments of incontinent nursing home patients was measured. Use of the activators of the invention reduced the total bacterial colony counts by around 99.9%, while the gram negative organisms were totally eliminated.
The solid activator bodies are stable during storage at ambient temperatures, and surface portions thereof rapidly disperse in water when introduced into standard washing equipment. Preferably, the solid activator bodies are subjected to hot, pressurized water so as to create a dispersion containing from about 0.1-10% by weight activator composition in water, and more preferably from about 0.5-5% by weight thereof. Such dilute dispersions generally contain from about 0.002-2% by weight TAED, and more preferably from about 0.015-0.75% be weight TAED.
FIG. 1 illustrates washing and/or cleaning equipment 10 in accordance with the present invention. Equipment 10 includes timer assembly 12, first spray-equipped bowl 14, second spray-equipped bowl 16, and washing machine 18. Timer assembly 12 has first solenoid valve 20, second solenoid valve 22, and main branched water pipe 24 connected to valves 20 and 22. Water lines 26, 28 respectively extend from valves 20, 22 first and second bowls 14, 16. Conventional piping 30-34 interconnects the outlets of bowls 14, 16 with washing machine 18.
As illustrated, first bowl 14 contains first body 38 including the preferred bleaching composition. Similarly, second bowl 16 contains second activator body 40.
In operation, timer 12 selectively activates first and second solenoid valves 20, 22 on a pre-determined timed basis. Upon activation, the valves 20, 22 open to supply water from water pipe 24 (connected to a water supply) to first bowl 14 by way of line 26 and to second bowl 16 via line 28. Upon receipt of water in the bowls 14,16, bodies 38, 40 begin to dissolve. The effluent from first bowl 14 containing dissolved bleaching composition flows via piping 30, 34 into washing machine 18; similarly, the underflow from bowl 16 passes through piping 32, 34 to machine 18. In particular, the dispersed bleaching and activator compositions are introduced into a conventional washing and/or cleaning solution within the washing chamber of machine 18. In the preferred embodiment, timer 12 opens solenoid valves 20, 22 long enough so that surface portions of bodies 38,40 dissolve to the desired extent, yielding bleach and activator dispersions of appropriate concentration for delivery to machine 18. The introduction of the bleach and activator dispersions can be simultaneous or seriatim.
The following table sets forth approximate broad, preferred and most preferred ranges for the essential and optional ingredients of the solid activator compositions of the invention, where all ranges are given on the basis of percent by weight of the total activator body composition.
TABLE 2______________________________________ Broad Preferred Most Preferred Range Range RangeIngredient (% by wt.) (% by wt.) (% by wt.)______________________________________Tetra acetyl ethylene diamine 2-20 3-15 6-12Phosphate sequestering agent 20-60 25-50 35-45Surfactant 0.5-15 2-10 3-7Non-phosphate solidifying agent 2-25 4-20 8-15Dispersing agent 0.5-10 2-8 3-7Water 10-50 20-40 25-35______________________________________ | Solid activator bodies for activating oxygen-based bleach at relatively low temperatures are provided which preferably include respective quantities of tetra acetyl ethylene diamine (TAED), phosphate sequestering agent, non-phosphate solidifying agent, surfactant and water. The activator bodies are readily dispersable in hot water to form dilute dispersions which can be added directly to cleaning equipment along with oxygen-based bleach. The activator enhances bleaching effectiveness and generates peracetic acid, a potential antimicrobial. | 2 |
BACKGROUND OF THE INVENTION TITLE OF THE INVENTION
The invention relates to a control device for the load-dependent connection of a hydraulic stand-by motor to a base-load motor.
In ground-boring machines with a hydraulic rotational drive, e.g. rock drilling and gimlet machines, it is known to drive the drilling shaft with a rotational drive having two hydraulic motors. Normally, only one of the motors, i.e. the one forming the base-load motor, is activated. If the resistance against rotation increases so that the base-load motor is no longer able to provide the necessary torque, a stand-by motor is switched on which supports the base-load motor in such cases. Usually, both motors are of the same construction and have the same capacity. Both motors are permanently engaged with the same gear wheel of the rods to be rotated. The control device for connecting the stand-by motor consists of a manually operable valve arranged near both engines. In order to operate the control device, the operator must walk up to the control device disposed near the motors and switch it over. If the motors are arranged on a carriage that is displaceable along a derrick, an operator will have to climb the derrick in order to operate the control device. This is not only time-consuming and expensive, but also hazardous.
SUMMARY OF THE INVENTION
It is the object of the present invention to provide a control device of the kind defined in the precharacterising part of claim 1, which works automatically, causes no loss of time during switching and excludes malfunctions.
The object is solved, according to the present invention, with the features of claim 1.
In the control device of the present invention, the stand-by motor is connected in dependence of the working pressure prevailing at the base-load motor, when this working pressure has reached an upper limit value.
In a case where the hydraulic power is provided to the motors by a volume controlled pump that produces a substantially more constant quantity delivered per time unit, the pressure at the base-load motor varies with the load. Since the load existing before and after switching may be assumed to be the same, the working pressure at the base-load motor drops as soon as the stand-by motor is switched on. Supposing that both engines are equal, switching on the stand-by motor will cause the working pressure to sink to half the previous working pressure that prevailed when only the base-load motor had been active. If the control device would always respond to the same limit value only, the base-load motor would be turned off after the switching on of the stand-by motor and the decrease in the working pressure. This would result in a repeated activation and deactivation of the stand-by motor. According to the present invention, the control device shows a hysteretic behavior. In other words: the stand-by motor is turned on upon reaching an upper limit pressure and the deactivation of the stand-by motor is effected at a lower limit pressure that is considerably less than the upper limit pressure.
The control device of the present invention is not only suitable for controlling hydraulic rotary motors, but also for controlling hydraulic linear motors such as piston-cylinder units, for instance. In this case, too, there is the problem that, usually, a single piston-cylinder unit covers the base load and that upon the occurrence of a higher load, however, a further piston-cylinder unit must be joined in.
The present invention allows to use the higher delivery pressures of modern hydraulic pumps to perform a given work which is done by a single base-load motor operating at high working pressures. Only when the output of the base-load motor is insufficient, will the stand-by motor be switched on automatically to support the base-load motor. The deactivation of the stand-by motor is also done fully automatic. In this manner, the aggregate of the pump can be operated at high efficiency and at a good energy exploitation with a comparatively low mass flow of pressure.
In the simplest case, the control device may be designed such that it measures the working pressure at the base-load motor and provides a signal upon reaching either the upper limit pressure or the lower limit pressure. This signal is then processed in dependence of the operational state of the base-load motor in order to generate a control signal for the stand-by motor. This signal processing may be done electrically, i.e. by a microprocessor. Under the rough conditions of implementation with ground-boring devices and the like, a hydraulic control and switching device may be more advantageous since it is less susceptible to troubles and damages than an electric control device.
It is not necessary that the base-load motor is a single motor. The base-load motor may consist of two or even more individual motors that are permanently activated and that may be joined by a stand-by motor in case of need. Further, it is possible to switch on a plurality of stand-by motors in a step-wise manner depending on the working pressure, first activating one stand-by motor upon reaching an upper limit pressure. If the upper limit pressure is again reached with both motors being activated, a second stand-by motor may be switched on.
The control device of the present invention is designed particularly for implementation in ground and rock drilling machines having a drill tool provided at the front end of the drill rod. In this case, the control device is used for the rotary drive of the drill rod.
The following is a detailed description of embodiments of the present invention with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a first embodiment of the control device of the invention with a control slide and a regulating slide at low load and during clockwise rotation;
FIG. 2 is an illustration of the device of FIG. 1 at high load and during clockwise rotation;
FIG. 3 illustrates the control device at low load and during counterclockwise rotation;
FIG. 4 illustrates the control device at high load and during counterclockwise rotation;
FIG. 5 is a diagram for illustrating the dependence between the path of displacement of the control slide and the working pressure for the embodiment of FIGS. 1-4;
FIG. 6 is a second embodiment at low load and during counterclockwise rotation;
FIG. 7 is the second embodiment at high load and during counterclockwise rotation;
FIG. 8 is the second embodiment during clockwise rotation, both at high and at low load; and
FIG. 9 is a diagram for illustrating the dependence between the path of displacement of the control slide and the working pressure for the embodiment of FIGS. 6-8.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the embodiment of FIGS. 1 to 5, a pump 10 supplies pressure fluid from a sump 11 to a pressure conduit 12. A non-pressurized reflux line 13 leads back to the reservoir 11. The conduits 12 and 13 are connected with supply conduits 15 and 16 through a manually operable direction control valve 14. These supply conduits are immediately connected to the base-load motor M1. The base-load motor M1 drives a pinion 17 that meshes with a gear wheel 18 connected with the output shaft 18 that may drive the drill rods of a drilling device for example. Moreover, the gear wheel 18 meshes with the pinion 20 that is coupled to the output shaft of the stand-by motor M2.
When the direction control valve 14 is in its position 14a, as illustrated in FIG. 1, the supply conduit 15 is connected with the pressure conduit 12 and the supply conduit 16 is connected with the reflux conduit 13, which causes the clockwise rotation of the baseload motor M1.
In the position 14b of the direction control valve 14, the pressure line 12 is coupled directly with the reflux conduit 13 and both motors are deactivated.
In the position 14c of the direction control valve 14, the supply conduit 16 is connected with the pressure conduit 12 and the supply conduit 15 is connected with the reflux conduit 13. In this state, the base-load motor M1 will rotate counterclockwise.
The supply conduits 15, 16 are connected with the switching device 21 in order to switch on the stand-by motor. The switching device 21 has a shuttle valve 22, a control slide 23 and a regulating slide 24. The shuttle valve 22 is controlled by the pressures of the supply conduits 15, 16. It connects that supply conduit with a pressure inlet leading to the control slide 23, which holds the higher pressure, and connects the other supply line, the one holding less pressure, to a reflux inlet 26 leading to the control slide.
The control slide 23 is accommodated displaceably within a housing 27 having an elongate bore 28 of constant diameter. Only one end of the housing is provided with a portion 28a of the bore with a larger diameter. The control slide 23 has three blocking surfaces 30, 31, 32 between which passages 33, 34 are arranged in the form of control grooves. In the portion 28a of the bore, there is provided a piston surface 35 of enlargened diameter.
The control slide 23 has a bore 36 going through its entire length. A spring 37 supported in the housing 27 or cylinder urges the control slide 23 towards the portion 28a.
The pressure inlet 25 is connected with the one end of the housing 27 so that both end faces of the control slide 23 are always subjected to the same pressure through the bore 36. Since the piston surface 35 is larger than the end face facing to the spring 37, the hydraulic force is predominant, trying to compress the spring 37.
A conduit 38 leads from the pressure inlet 25 into the cylinder chamber of the control slide. This conduit 38 is interrupted by the blocking surface 30 and is continued by the conduit portion 38a. A further conduit 39 leads from the pressure inlet 25 into the cylinder. This conduit 39 ends in a portion where the passage 33 is located in the rest position. The conduit is continued by the conduit 39a.
A conduit 40 leads from the reflux inlet 26 into the cylinder. In the rest position of the control slide, this conduit 40 meets with the blocking surface 31 and it is continued by a conduit 40a that is connected with the conduit 39a and forms the first control conduit 41.
In the rest position of the control slide, a conduit 42 leads from the reflux inlet 26 to the passage 34 and continues as the conduit 42a connected with the conduit 38a and forming the second control conduit 43.
Further, the reflux inlet 26 is connected with the portion 28a of enlargened diameter so that this portion is permanently non-pressurized.
Since the hydraulic force acting on the end wall 23b facing away from the spring 37 is greater than the hydraulic force acting on the opposite smaller end wall 23a, and since the pressure forces acting in the passages 33 and 34 compensate each other, a force is exerted on the control slide 23 that is proportional to the working pressure at the pressure inlet 25 and which tends to compress the spring 37. Accordingly, the control slide 23 takes a position proportional to the working pressure.
In the rest position, i.e. when no working pressure is present, the blocking surface 30 interrupts the conduit 38 and the blocking surface 31 interrupts the conduit 40. In contrast thereto, the passage 33 connects the conduit 39 with conduit 39a and the conduit 42 with conduit 42a. As a result, the first control conduit 41 is pressurized, as illustrated in FIG. 1, while the second control conduit 43 is non-pressurized.
The two control conduits 41 and 43 control the regulating slide 24 that is displaceable within a housing 44. The control conduit 41 acts on the one end 45 and the control conduit 43 acts on the opposite end 46 of the regulating slide 24. The control conduit with the higher pressure shifts the regulating slide 24 towards the other control conduit. The other hydraulic pressures compensate within the regulating slide 24 so that the regulating slide 24 is urged either in the one or the other direction by the control conduits 41 43 exclusively.
The cylinder chamber 47 in which the regulating slide 24 is displaceable, is provided with control grooves 48, 49, 50 and 51. Its two ends are connected with relief conduits 52. The regulating slide 24 has passages 53 and 54 in the form of control grooves that may connect two of the control grooves of the cylinder, respectively.
The control grooves 49 and 50 are connected with the two connections of the stand-by motor M2, the control groove 48 is connected with the supply conduit 16 and the control groove 51 is connected with the supply line 15.
With a low load at the drill rods 19, the control slide 23 takes the position illustrated in FIG. 1, whereby the control conduit 41 is pressurized and the control conduit 43 is non-pressurized. Thereby, the regulating slide 24 is shifted into the right end position, in which both connections of the stand-by motor M2 are connected through the control grooves 49 and 50. The control groove 48 is non-pressurized, while the control groove 51 is pressurized, however, these grooves are each blocked. Due to the short-circuit of the stand-by motor M2, this motor rotates at idle with the base-load motor M1. Thus, the stand-by motor acts as a pump working at idle, but performing no actual work. The actual work is performed entirely by the base-load motor M1.
When the load moment increases, the pressure to be provided by the quantity-regulated pump 10 increases and the control slide 23 is displaced according to this amount of pressure against the action of the spring 37. In doing so, the blocking surfaces 31 and 32 move into the area of the conduits 39 and 42. No change occurs in the conduits 39a and 42a for they are cut off. The regulating slide thus remains in the position previously taken. Accordingly, the drive is effected by the base-load motor M1 exclusively, as illustrated in FIG. 1.
FIG. 2 illustrates the state in which the pressure at the base-load motor and, accordingly, at the control slide has reached the upper limit pressure. In this state, the conduits 38 and 38a are connected by the control groove 33 and the control conduit 43 is pressurized, while the control conduit 41 is non-pressurized due to the connected conduits 40 and 40a.
Thereby, the regulating slide 24 is urged into the left end position in which the control groove 54 connects the passages 50 and 51, while the control groove 53 connects the passages 48 and 49. Pressure is supplied to the stand-by motor M2 at a conduit 55 via the passage 50 and its other conduit 56 becomes non-pressurized via the passage 49. As illustrated in FIG. 2, the stand-by motor M2 is driven in the same sense of rotation as the main-load motor M1.
In FIG. 5, the ordinate represents the pressure p, whereas the abscissa is representative of the displacement path D of the control slide 23 or the force F of the spring 37. The displacement path D and the force F of the spring extend along the straight line 60. The portion 61 represents the bias of the spring 37. In this portion, the control slide 23 is not displaced. In the portion 62, the control slide 23 is displaced continuously against the action of the spring 37 up to an upper limit pressure p o until the state illustrated in FIG. 2 has been reached, which corresponds to a value of p o =180 bar. Then, the stand-by motor M2 is switched on. Since both motors M1 and M2 are of the same construction, the pump pressure at 63 is instantaneously reduced by half, namely to 90 bar, given that the load moment does not change during the switching. The line 64 represents the case in which both motors M1 and M2 are driven and the load still increases. As a result, the working pressure also rises and it may exceed the upper limit pressure p o defined by the control slide 23 and reach the capacity limit of the pump.
The line 65 is representative of the case in which the load drops again with both motors M1 and M2 activated.
Upon reaching the lower limit pressure p u that is considerably lower than half the upper limit pressure p o , the stand-by motor M2 is deactivated as at 66. This is done when the control slide 23 has again taken the position illustrated in FIG. 1, i.e. at the pressure that is determined by the bias of the spring 37. In the present embodiment, this lower limit pressure p u is 50 bar. Line 67 in FIG. 5 represents the case in which the rotation of the drill rods is again done exclusively by means of the base-load motor M1, as indicated at 62.
The diagram of FIG. 5 has been described for an example in which both motors M1 and M2 have the same capacity. If these motors have different capacities, i.e. the motor M1 has the capacity P 1 and the motor M2 has the capacity P 2 , the lower limit pressure p u must be selected to be smaller than P 1 /(P 1 +P 2 )×p o . This is also true for the case where the base-load motor consists of a plurality of individual motors.
Referring to FIGS. 3 and 4, the following is a description of the conditions for the counterclockwise rotation of the motors, i.e. when the direction control valve 14 is set at the position 14c. In this case, the supply conduit 16 is pressurized, while the supply conduit 15 is not. Thus, the base-load motor M1 is driven in counterclockwise direction first. The direction control valve 22 has the effect that the control slide 23 is operated in the same way as in clockwise rotation.
In the case of a low load, i.e. when the working pressure of the base-load motor M1 is lower than the upper limit pressure p o , the passages 49 and 50 of the housing of the regulating slide 24 are again connected by the control groove 53 of the regulating slide, as illustrated in FIG. 3, whereby the conduits 55 and 56 of the stand-by motor M2 are connected and the stand-by motor runs at idle.
Upon reaching the upper limit pressure p o , the passage 49 is connected with the now pressurized passage 48, as illustrated in FIG. 4, and the passage 50 is connected with the non-pressurized passage 51. Thus, the stand-by motor M2 is driven counterclockwise.
The stand-by motor is deactivated again by the control slide 23 taking the initial position shown in FIG. 3.
In the embodiment of FIGS. 6 to 8, the switching device has a control slide 70 which also has the functions of the regulating slide. This control slide 70 is arranged in a cylindrical housing 71 with a cylindrical bore 72. At the one end of the cylindrical housing 71 the cylindrical bore 72 has a portion 72a of an enlargened diameter. This portion 72a is permanently connected with the reflux conduit, i.e. with the sump 11, via a conduit 73. A spring 74 is supported at the opposite end of the cylindrical housing 71, which presses against the one end of the control slide 70. At the portion 72a, the control slide has an enlargement 75, the end of which facing away from the non-pressurized chamber forms an abutment face A h . In the present embodiment, the control slide 70 is hollow so that the pressure prevailing at its two ends is always equal. The end of the control slide facing toward the spring 74 forms the one end surface A 1 and the end facing away from the spring forms the other end surface which is larger than A 1 and has a dimension of A 1 +A a . The excess surface forms the control surface A a .
An annular groove 76 is formed in the cylindrical housing 71, which may cooperate with radial passages 77 of the control slide 70. The supply conduit 16 leads into the one end of the cylindrical housing 71 and a conduit 78 is connected to the annular groove 76 and the end of the portion 72a that is located on the side which, with respect of the enlargement 75, is opposite the connection of conduit 73. Conduit 78 is connected, on the one hand, to the one connection 79 of the standby motor M2 and, on the other hand, to the inlet of a shuttle valve 80 which is controlled by the pressures from the supply conduits 15 and 16.
When pressure prevails in the supply conduit 16, as in FIG. 6, while the supply conduit 15 is non-pressurized, the shuttle valve 80 is in the position 80a in which the conduit 78 is connected with the conduit 15. Behind the corresponding connection 81 of the shuttle valve 80, a check valve 82 is provided that allows passage of pressure fluid only in the direction from the supply conduit 15 to the conduit 78, while it blocks passage in the other direction. The other connection 83 of the shuttle valve 80 is connected with the supply conduit 16. In the position 80b of the shuttle valve 80, the conduit 78 is connected with the outlet 83 and thus with the supply conduit 16.
The second embodiment operates as follows: in the illustration of FIG. 6, the motor M1 is switched to counterclockwise rotation by the direction control valve 14. The supply conduit 16 is pressurized, whereas the supply conduit 15 is not. At low load and low working pressure, the spring 74 urges the control slide 70 into the right-hand end position. In this case, the passages 77 are spaced from the annular groove so that the conduit 78 is not supplied with pressure. The shuttle valve 80 is in the position 80a. The stand-by motor M2 is in a short-circuit condition. The stand-by motor M2 that is driven at idle by the base-load motor M1 moves hydraulic oil without pressure from its connection 84 through the check valve 82 that is open in this direction and the shuttle valve 80 to the connection 79. This establishes a closed short-circuit loop across the stand-by motor M2. Oil is circulated in this short-circuit loop without pressure.
At a greater load, the working pressure at the supply conduit 16 rises. When the force generated at the control surface A a exceeds the bias of the spring 74, the control slide starts to move against the action of the spring 74. Upon reaching the upper limit pressure, the passages 77 move into the area of the annular groove 76. As indicated in FIG. 7, the conduit 78 is then supplied with pressure from inside the control slide 70, whereby pressure also reaches the abutment face A h . The abutment face A n is larger than the control surface A a . The ratio A h /A a is preferably about 60/40. When the working pressure drops to half the upper limit pressure p o after the stand-by motor M2 has been switched on, the surfaces A h and A a of the control slide 70 supporting each other together still keep the spring 74 in a compressed state.
The pressure in the conduit 78 drives the stand-by motor M2 in the same sense of rotation as the base-load motor M1. The shuttle valve 80 remains in the state it was in before. The pressure at the conduit 78 is blocked at the check valve 82.
Only when the pressure at the control slide 70 becomes so low that the surfaces A h and A a cannot withstand the counterforce exerted by the spring 74, will the control slide 70 move backwards at a lower limit pressure p u . When the passages 77 have left the area of the annular groove 76, no more pressure is available for driving the stand-by motor M2 so that the state illustrated in FIG. 6 is obtained again.
The operation of the switching device of FIG. 6 and 7 is illustrated in FIG. 9. The ordinate represents the pressure p in bar and the abscissa represents the path D of the control slide 70 from its rest position and the force F of the spring 74. The values D and F vary in dependence of the working pressure p, as indicated by the straight line 90, given that the spring has a linear characteristic. The bias of the spring is designated by 91.
Upon an increase of the working pressure along the line 92, the stand-by motor M2 is switched on when the upper limit pressure p o of 180 bar, as indicated at 93, is reached, whereby the working pressure p drops to one half, i.e. 90 bar, given that both motors are equal. Thereafter, both motors operate commonly along line 94, the working pressure possibly also exceeding the upper limit pressure p o to an extent allowed by the pump 10. With the working pressure sinking, i.e. at reduced torque, both motors keep working commonly (line 95) until the lower limit pressure p u of approximately 40 bar is reached. The lower limit pressure is determined by the ratio between the surfaces A a and A h . At 96, the stand-by motor M2 is switched off which leads to an increase in working pressure from 40 to about 70 bar. Subsequently, the operation continues along line 97 only with the base-load motor M1.
The above explanation of the embodiment of FIGS. 6 and 7 only referred to the counterclockwise rotation. When the direction control valve 14 is switched into the position 14a (FIG. 8), the drive rotates clockwise and only with both motors M1 and M2 rotating together. The supply conduit 15 is pressurized and the supply conduit 16 becomes non-pressurized. Thus, the shuttle valve 80 is switched into position 80b in which it blocks the pressure prevailing at its connection 81. The shuttle valve 80 connects the connection 79 of the stand-by motor M2 to the non-pressurized supply conduit 16 via the conduit 83. Thus, the stand-by motor M2 is supplied with pressure at its connection 84 through the supply conduit 15, while the outlet is effected via the connection 79, the shuttle valve 80 and the conduit 83 to the supply conduit 16. | A hydraulic base-load motor (M1) drives a load with the working pressure generated at the motor rising with the load. When the working pressure reaches an upper limit pressure, a hydraulic stand-by motor (M2) is switched on. Since the pressure drops upon switching on the stand-by motor, the control device is designed such that, upon reaching a lower limit pressure, it deactivates the stand-by motor again, the lower limit pressure being less than half the upper limit pressure. This switching hysteresis prevents a repeated switching over of the stand-by motor. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is based upon and claims the benefit of priority of the prior Japanese Patent Application No. 2009-151454, filed on Jun. 25, 2009, the entire contents of which are incorporated herein by reference.
FIELD
The embodiments discussed herein are related to an air conditioning installation and an air conditioning control method that control the quantity of air from an air conditioner.
BACKGROUND
In recent years, a rack is installed in a space called data center or server room. IT devices, such as servers and network devices, are stacked in the rack. Since the IT devices include functional parts, for example, CPUs, the IT devices use power and generate heat. The temperatures of the IT devices have to be maintained at a certain temperature or lower for assurance of the operation. Hence, an air conditioning installation is used. The air conditioning installation cools the IT devices in the rack by blowing cooling air from an air conditioner.
The air circulation by the air conditioning installation will be described below. The air conditioner blows the cooling air, to supply the rack with the cooling air. Fans embedded in the IT devices in the rack suck the cooling air. The cooling air cools the functional parts, for example, CPUs. The cooling air absorbs the heat of the IT devices and becomes the heated air. The heated air at a relatively high temperature is exhausted through exhaustion ports in the back surfaces of the IT devices. Then, the air conditioner takes in the exhausted air.
As the heat density of the IT devices in the rack increases, the heat value per rack tends to increase. A hot spot that may be generated because the exhausted air flows around the rack and the hot spot may be a bottleneck. In particular, a hot spot may be generated in the data center because the quantity of cooling air at a relatively low temperature supplied from the air conditioner is insufficient for the quantity of air to be used for cooling the IT devices. For example, when the supplied air quantity for a rack is insufficient, the insufficiency is covered with the exhausted air at a relatively high temperature from that rack or a rack adjacent thereto. Consequently, the introduction temperature of the rack increases.
A technique that reduces the likelihood of generation of such a hot spot may be a method that reduces the likelihood of generation of a hot spot by installing an additional air conditioner to increase the quantity of cooling air. Alternatively, there is a technique that reduces the likelihood of generation of a hot spot by installing a local air conditioner near the position at which a hot spot is generated (for example, see Japanese Laid-open Patent Publication No. 2006-114669).
Still alternatively, there is another technique that reduces the likelihood of generation of a hot spot by providing an aisle capping to divide an aisle into a cool aisle for circulation of the cooling air and a hot aisle for circulation of the heated air (for example, see Japanese Laid-open Patent Publication No. 2004-184070 and No. 2005-260148). Yet alternatively, there is a technique that reduces the likelihood of generation of a hot spot by combining the local air conditioner with the aisle capping, and providing a closed space in a data center (for example, see International Publication No. WO2004/083743 (corresponding to Japanese Laid-open Patent Publication No. 2006-526205) and International Publication No. WO2005/122664 (corresponding to Japanese Laid-open Patent Publication No. 2008-502082)).
Yet alternatively, there is a technique that monitors the introduction temperature state of the rack, detects the presence of a hot spot through comparison with a re-circulation index or a prepared template value, and controls the quantity and temperature of the air from the air conditioner (for example, see International Publication No. WO2003/089845 (corresponding to Japanese Laid-open Patent Publication No. 2006-504919) and International Publication No. WO2004/107142 (corresponding to Japanese Laid-open Patent Publication No. 2007-505285)).
However, with the technique that provides the additional air conditioner or the local air conditioner, the power consumption may increase because the additional air conditioner or local air conditioner is operated. Consequently, it is difficult to efficiently cool the rack.
With the technique that provides the aisle capping, the aisle is divided into the cool aisle for the circulation of the cooling air and the hot aisle for the circulation of the heated air. Unfortunately, the balance between the quantity of the air to be used for cooling the rack, and the supplied quantity of the air from the air conditioner is not considered. Thus, for example, if the supplied quantity of the cooling air is insufficient, the heated air may flow into the cool aisle. Consequently, the rack may not be properly cooled.
With the technique that monitors the introduction temperature state of the rack, detects the presence of a hot spot, and controls the air quantity, the air quantity is controlled only after the temperature increases. If the temperature rapidly increases, the response may be delayed. It is difficult to properly cool the rack.
SUMMARY
According to an aspect of the invention, an installation for cooling an electronic device provided in a room, includes an air conditioner having an air outlet for blowing cooling air to the room; a first detector adjacent to the air outlet of the air conditioner, for detecting a temperature of the cooling air; a rack accommodating the electronic device, the rack having an air inlet for receiving the cooling air from the air conditioner and an air outlet for exhausting air to the room; a second detector adjacent to the air inlet of the rack, for detecting a temperature of air received through the air inlet of the rack; and a controller for acquiring the temperature detected by the first detector and the temperature detected by the second detector, and controlling a quantity of the cooling air blown from the air outlet of the air conditioner so as to decrease a difference between the temperatures detected by the first and the second detectors.
The object and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the claims.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 is a block diagram of a configuration of an air conditioning installation according to a first embodiment;
FIG. 2 is a block diagram of a configuration of an air conditioning installation according to a second embodiment;
FIG. 3 is a block diagram of a configuration of an air conditioning control unit according to the second embodiment;
FIG. 4 is a flowchart explaining a process of the air conditioning installation according to the second embodiment;
FIG. 5 is a block diagram of a configuration of an air conditioning installation according to a third embodiment; and
FIG. 6 illustrates a computer that executes an air quantity control program.
DESCRIPTION OF EMBODIMENTS
An air conditioning installation, an air conditioning control method, and an air conditioning control program according to embodiments of the invention will be described below with reference to the attached drawings.
First Embodiment
In the following embodiment, a configuration and a process of an air conditioning installation 1 according to a first embodiment will be described, and then advantages attained by the first embodiment will be described.
The configuration of the air conditioning installation 1 according to the first embodiment will be described with reference to FIG. 1 . FIG. 1 explains the configuration of the air conditioning installation 1 according to the first embodiment.
Referring to FIG. 1 , the air conditioning installation 1 of the first embodiment includes an air conditioner 2 that blows cooling air to a rack 3 , the rack 3 that receives the cooling air from the air conditioner 2 and exhausts heated air, temperature detectors 4 A to 4 D that detect temperatures, and an air quantity control unit 5 that controls the quantity of the air from the air conditioner 2 . In FIG. 1 , hatched arrows indicate the flow of the cooling air, and white arrows indicate the flow of the heated air.
The air conditioner blow temperature detector 4 A detects the temperature of the cooling air 51 blown from an outlet (not illustrated in FIG. 1 ) of the air conditioner 2 . The rack introduction temperature detector 4 B detects the temperature of the cooling air 52 when the rack 3 receives the cooling air through an inlet (not illustrated in FIG. 1 ) of the rack 3 .
The air quantity control unit 5 controls the quantity of air from the air conditioner 2 to decrease the difference between the temperature detected by the air conditioner blow temperature detector 4 A and the temperature detected by the rack introduction temperature detector 4 B.
For example, if the temperature of the cooling air when the rack 3 receives the cooling air is higher than the temperature of the cooling air blown from the air conditioner 2 , the air quantity control unit 5 determines that the air quantity is insufficient, and increases the quantity of air from the air conditioner 2 to decrease the temperature difference.
The rack exhaustion temperature detector 4 C detects a rack exhaustion temperature that is the temperature of the heated air 53 exhausted from an exhaust outlet (not illustrated in FIG. 1 ) of the rack 3 , which has received the cooling air 51 blown from the outlet of the air conditioner 2 . The air conditioner return temperature detector 4 D detects an air conditioner return temperature that is the temperature of the heated air 54 when the air conditioner 2 takes in through an inlet (not illustrated in FIG. 1 ) of the air conditioner 2 .
The air quantity control unit 5 controls the quantity of air from the air conditioner 2 to decrease the difference between the rack exhaustion temperature detected by the rack exhaustion temperature detector 4 C and the air conditioner return temperature detected by the air conditioner return temperature detector 4 D.
For example, if the air quantity control unit 5 judges that the rack exhaustion temperature is higher than the air conditioner return temperature, the cooling air may be excessive. The air quantity control unit 5 determines that the cooling air may cool even the heated air that does not have to be cooled, and decreases the quantity of air from the air conditioner 2 to decrease the difference between the rack exhaustion temperature and the air conditioner return temperature.
As described above, since the air conditioning installation 1 can efficiently and properly cool the rack 3 by balancing the quantity of air to be used for cooling the rack 3 and the supplied quantity of air from the air conditioner 2 , the rack 3 can be efficiently and properly cooled by decreasing the waste of the cooling air from the air conditioner 2 .
Second Embodiment
In the following embodiment, a configuration and a process of an air conditioning installation 100 according to a second embodiment will be described, and then advantages attained by the second embodiment will be described.
[Configuration of Air Conditioning System]
The configuration of the air conditioning installation 100 according to the second embodiment will be described with reference to FIG. 2 . FIG. 2 is a block diagram of the configuration of the air conditioning installation 100 according to the second embodiment. Referring to FIG. 2 , the air conditioning installation 100 includes an air conditioner 2 , a rack 3 , an air conditioning control unit 10 serving as an air quantity control unit, temperature detectors 20 A to 20 D, an exhaustion guide path 30 , and an air hole 40 . The air conditioning control unit 10 is connected with the temperature detectors 20 A to 20 D through a LAN.
The air conditioning installation 100 has a double floor structure providing a space below a floor (upper space) and a space above the floor (lower space). The rack 3 is installed on the floor (in the space above the floor). In the air conditioning installation 100 , the cooling air blown from the air conditioner 2 passes through the space below the floor, and is supplied to the rack 3 . In FIG. 2 , hatched arrows indicate the flow of the cooling air, and white arrows indicate the flow of the heated air.
The air conditioner 2 blows the cooling air 51 to the rack 3 from an outlet (not illustrated in FIG. 2 ) of the air conditioner 2 , and takes in the heated air 54 exhausted from the rack 3 through an inlet (not illustrated in FIG. 2 ) of the air conditioner 2 . In particular, the air conditioner 2 supplies the cooling air 52 to the rack 3 installed on the floor (in the space above the floor) by blowing the cooling air 51 to the space below the floor. Since the rack 3 has IT devices mounted thereon, the rack 3 receives the cooling air 52 supplied from the air conditioner 2 through an inlet (not illustrated in FIG. 2 ) of the rack 3 , and exhausts the heated air 53 to the space above the floor through an exhaust outlet (not illustrated in FIG. 2 ) of the rack 3 .
The exhaustion guide path 30 is a structure that separates an aisle into a hot aisle and a cool aisle. The hot aisle is an area included in the space above the floor where the rack 3 is installed. Only the heated air from the rack 3 is collected in this area. In the embodiment illustrated in FIG. 2 , the heated air indicated by the white arrows is circulated in this area. The cool aisle is an area in which only the cooling air blown from the air conditioner 2 is collected. In the embodiment illustrated in FIG. 2 , the cooling air indicated by the hatched arrows is circulated in this area. The air hole 40 is a hole that allows the air in the hot aisle and the air in the cool aisle to be exchanged.
The air conditioner blow temperature detector 20 A detects an air conditioner blow temperature that is the temperature of the cooling air 51 blown from the outlet of the air conditioner 2 to the rack 3 . The rack introduction temperature detector 20 B detects a rack introduction temperature that is the temperature of the cooling air 52 when the rack 3 receives the cooling air through the inlet of the rack 3 . The rack exhaustion temperature detector 20 C detects a rack exhaustion temperature that is the temperature of the heated air 53 exhausted from the exhaust outlet of the rack 3 , which has received the cooling air 52 . The air conditioner return temperature detector 20 D detects an air conditioner return temperature that is the temperature of the heated air 54 when the air conditioner 2 takes in through the inlet of the air conditioner 2 .
The air conditioning control unit 10 controls the quantity of air from the air conditioner 2 in accordance with the temperatures detected by the temperature detectors 20 A to 20 D. Now, a detailed configuration of the air conditioning control unit 10 will be described with reference to FIG. 3 . FIG. 3 is a block diagram of the configuration of the air conditioning control unit 10 according to the second embodiment. Referring to FIG. 3 , the air conditioning control unit 10 includes a temperature judgment unit 10 a and an air quantity control unit 10 b.
The temperature judgment unit 10 a judges whether the rack exhaustion temperature detected by the rack exhaustion temperature detector 20 C is higher than the air conditioner return temperature detected by the air conditioner return temperature detector 20 D. The temperature judgment unit 10 a also judges whether the rack introduction temperature detected by the rack introduction temperature detector 20 B is higher than the air conditioner blow temperature detected by the air conditioner blow temperature detector 20 A.
In particular, the temperature judgment unit 10 a acquires in real time the information of the temperatures detected by the temperature detectors 20 A to 20 D through the LAN. To judge whether the rack exhaustion temperature “Tr_out” detected by the rack exhaustion temperature detector 20 C is higher than the air conditioner return temperature “Tac_in” detected by the air conditioner return temperature detector 20 D, the temperature judgment unit 10 a judges whether a condition “Tr_out”−“Tac_in”>0 is satisfied.
If the temperature judgment unit 10 a judges that the condition “Tr_out”−“Tac_in”>0 is satisfied, the temperature judgment unit 10 a gives the air quantity control unit 10 b an instruction to decrease the quantity of air from the air conditioner 2 . In contrast, if the temperature judgment unit 10 a judges that the condition “Tr_out”−“Tac_in”>0 is not satisfied, in order to judge whether the rack introduction temperature “Tr_in” is higher than the air conditioner blow temperature “Tac_out,” the temperature judgment unit 10 a judges whether a condition “Tr_in”−“Tac_out”>0 is satisfied.
If the temperature judgment unit 10 a judges that the condition “Tr_in”−“Tac_out”>0 is satisfied, the temperature judgment unit 10 a gives the air quantity control unit 10 b an instruction to increase the quantity of air from the air conditioner 2 . In contrast, if the temperature judgment unit 10 a judges that the condition “Tr_in”−“Tac_out”>0 is not satisfied, the temperature judgment unit 10 a does not control the air quantity.
The air quantity control unit 10 b controls the quantity of air from the air conditioner 2 to decrease the difference between the air conditioner blow temperature detected by the air conditioner blow temperature detector 20 A and the rack introduction temperature detected by the rack introduction temperature detector 20 B. Also, the air quantity control unit 10 b controls the quantity of air from the air conditioner 2 to decrease the difference between the rack exhaustion temperature detected by the rack exhaustion temperature detector 20 C and the air conditioner return temperature detected by the air conditioner return temperature detector 20 D.
In particular, if the air quantity control unit 10 b receives the instruction to decrease the quantity of air from the air conditioner 2 from the temperature judgment unit 10 a , which has judged that the rack exhaustion temperature is higher than the air conditioner return temperature, the air quantity control unit 10 b decreases the quantity of air from the air conditioner 2 .
In contrast, if the air quantity control unit 10 b receives the instruction to increase the quantity of air from the air conditioner 2 from the temperature judgment unit 10 a , which has judged that the rack introduction temperature is higher than the air conditioner blow temperature, the air quantity control unit 10 b increases the quantity of air from the air conditioner 2 .
In other words, the air conditioning control unit 10 determines that the cooling air is excessive if it is judged that the rack exhaustion temperature is higher than the air conditioner return temperature. For example, in the embodiment illustrated in FIG. 2 , if the rack exhaustion temperature is higher than the air conditioner return temperature, it may be considered that the air at the rack exhaustion temperature is cooled by the cooling air (indicated by arrow (a) in FIG. 2 ) flowing through the air hole 40 . The cooling air is excessive.
The air conditioning control unit 10 decreases the quantity of air from the air conditioner 2 . Thus, the quantity of the heated air in the hot aisle and the quantity of the cooling air in the cool aisle can be balanced, and the energy can be saved.
In some cases, the temperature of the heated air exhausted from the rack 3 may be decreased before the heated air is taken in by the air conditioner 2 not because of the cooling air flowing through the air hole 40 . It may be judged whether the rack exhaustion temperature “Tr_out” is higher by a predetermined threshold value than the air conditioner return temperature “Tac_in” detected by the air conditioner return temperature detector 20 D.
For example, the air conditioning control unit 10 may set “2° C.” as the predetermined threshold value. In this case, the air conditioning control unit 10 judges whether a condition “Tr_out”−“Tac_in”≧2° C. is satisfied. If the condition “Tr_out”−“Tac_in”≧2° C. is satisfied, the air conditioning control unit 10 decreases the air quantity.
Also, the air conditioning control unit 10 determines that the cooling air is insufficient if the rack introduction temperature is higher than the air conditioner blow temperature. For example, in the embodiment illustrated in FIG. 2 , if the rack introduction temperature is higher than the air conditioner blow temperature, it may be considered that the quantity of the cooling air is insufficient. It may be considered that the air at the rack introduction temperature is heated by the heated air (indicated by arrow (b) in FIG. 2 ) flowing through the air hole 40 . The cooling air is insufficient.
The air conditioning control unit 10 increases the quantity of air from the air conditioner 2 . Thus, the quantity of the heated air in the hot aisle and the quantity of the cooling air in the cool aisle can be balanced, and the rack 3 can be properly cooled.
In some cases, the temperature of the cooling air blown from the air conditioner 2 may be increased before the cooling air is received by the rack 3 not because of the heated air flowing through the air hole 40 . It may be judged whether the rack introduction temperature “Tr_in” is higher by a predetermined threshold value than the air conditioner blow temperature “Tac_out.”
For example, the air conditioning control unit 10 may set “2° C.” as the predetermined threshold value. In this case, it is judged whether a condition “Tr_in”−“Tac_out”≧2° C. is satisfied. If the condition “Tr_in”−“Tac_out”≧2° C. is satisfied, the air conditioning control unit 10 increases the air quantity.
Although the single air conditioner 2 cools the single rack 3 in the embodiment in FIG. 2 , a single air conditioner 2 may typically cool a plurality of racks 3 . In this case, the rack introduction temperature detector 20 B and the rack exhaustion temperature detector 20 C are provided for each rack. The air conditioning control unit 10 acquires in real time the information of the temperatures detected by the rack introduction temperature detector 20 B and the rack exhaustion temperature detector 20 C of each rack.
The air conditioning control unit 10 calculates the average of rack exhaustion temperatures of the respective racks 3 . The air conditioning control unit 10 handles the calculated value as a rack exhaustion temperature. The air conditioning control unit 10 controls the quantity of air from the air conditioner 2 to decrease the difference between the calculated average of the rack exhaustion temperatures and the air conditioner return temperature.
Also, the air conditioning control unit 10 handles the highest rack introduction temperature from among rack introduction temperatures of the respective racks 3 as a rack introduction temperature. The air conditioning control unit 10 controls the quantity of air from the air conditioner 2 to decrease the difference between the highest rack introduction temperatures and the air conditioner blow temperature. That is, if the plurality of racks 3 are provided, the racks 3 are cooled in accordance with the rack 3 at the highest introduction temperature because it is desirable to cool all racks 3 properly.
[Process by Air Conditioning System]
A process by the air conditioning installation 100 according to the second embodiment will be described with reference to FIG. 4 . FIG. 4 is a flowchart explaining the process of the air conditioning installation according to the second embodiment.
Referring to FIG. 4 , the rack exhaustion temperature detector 20 C in the air conditioning installation 100 detects the rack exhaustion temperature “Tr_out” that is the temperature of the heated air exhausted from the rack 3 , which has received the cooling air blown from the air conditioner 2 . In addition, the air conditioner return temperature detector 20 D detects the air conditioner return temperature “Tac_in” that is the temperature of the heated air when the air conditioner 2 takes in (step S 101 ).
The air conditioning control unit 10 judges whether the condition “Tr_out”−“Tac_in”>0 is satisfied (step S 102 ). If the air conditioning control unit 10 judges that the condition “Tr_out”−“Tac_in”>0 is satisfied (YES in step S 102 ), the air conditioning control unit 10 controls the air conditioner 2 to decrease the quantity of air from the air conditioner 2 (step S 103 ).
In contrast, if the air conditioning control unit 10 judges that the condition “Tr_out”−“Tac_in”>0 is not satisfied (NO in step S 102 ), the rack introduction temperature detector 20 B detects the rack introduction temperature “Tr_in” that is the temperature of the cooling air when the rack 3 receives the cooling air. In addition, the air conditioner blow temperature detector 20 A detects the air conditioner blow temperature “Tac_out” that is the temperature of the cooling air blown from the air conditioner 2 to the rack 3 (step S 104 ).
The air conditioning control unit 10 judges whether the condition “Tr_in”−“Tac_out”>0 is satisfied (step S 105 ). If the air conditioning control unit 10 judges that the condition “Tr_in”−“Tac_out”>0 is satisfied (YES in step S 105 ), the air conditioning control unit 10 controls the air conditioner 2 to increase the quantity of air from the air conditioner 2 (step S 106 ). In contrast, if the air conditioning control unit 10 judges that the condition “Tr_in”−“Tac_out”>0 is not satisfied (NO in step S 105 ), the air conditioning control unit 10 does not change the quantity of air from the air conditioner 2 , and the process returns to step S 101 .
Advantages of Second Embodiment
As described above, in the air conditioning installation 100 , the air conditioner blow temperature that is the temperature of the cooling air blown from the air conditioner to the rack is detected; and the rack introduction temperature that is the temperature of the cooling air when the rack receives the cooling air is detected. Then, the air conditioning installation 100 controls the quantity of air from the air conditioner to decrease the difference between the detected air conditioner blow temperature and the detected rack introduction temperature. Thus, the air conditioning installation 100 can efficiently and properly cool the rack by balancing the quantity of air to be used for cooling the rack and the supplied quantity of air from the air conditioner and hence by decreasing the waste of the cooling air from the air conditioner.
Also, in the air conditioning installation 100 according to the second embodiment, it is judged whether the rack introduction temperature detected by the rack introduction temperature detector is higher than the air conditioner blow temperature. If it is judged that the rack introduction temperature is higher than the air conditioner blow temperature, the quantity of air from the air conditioner is increased. That is, if the rack introduction temperature is higher than the air conditioner blow temperature, the quantity of the cooling air is insufficient and hence the heated air flows through the air hole, resulting in the cooling air being heated. The cooling air is insufficient.
The air conditioning control unit 10 increases the quantity of air from the air conditioner 2 . Thus, the rack can be properly cooled by balancing the quantity of air to be used for cooling the rack and the supplied quantity of air from the air conditioner.
Further, in the air conditioning installation 100 according to the second embodiment, when the plurality of racks are provided, the quantity of air from the air conditioner is controlled to decrease the difference between the highest rack introduction temperature from among the plurality of rack introduction temperatures and the air conditioner blow temperature. Accordingly, the waste of the cooling air from the air conditioner can be decreased, and hence the plurality of racks can be efficiently and properly cooled.
Further, in the air conditioning installation 100 according to the second embodiment, the rack exhaustion temperature that is the temperature of the heated air exhausted from the rack is detected, the rack which has received the cooling air blown from the air conditioner; the air conditioner return temperature that is the temperature of the heated air when the air conditioner takes in is detected; and the quantity of air from the air conditioner is controlled to decrease the difference between the rack exhaustion temperature and the air conditioner return temperature. Thus, the air conditioning installation 100 can efficiently and properly cool the rack by balancing the quantity of air to be used for cooling the rack and the supplied quantity of air from the air conditioner and hence by decreasing the waste of the cooling air from the air conditioner.
Further, in the air conditioning installation 100 according to the second embodiment, it is judged whether the detected rack exhaustion temperature is higher than the air conditioner return temperature. If it is judged that the rack exhaustion temperature is higher than the air conditioner return temperature, the quantity of air from the air conditioner is decreased. That is, if the rack exhaustion temperature is higher than the air conditioner return temperature, it may be considered that the air at the rack exhaustion temperature is cooled by the cooling air (indicated by arrow (a) in FIG. 2 ) flowing through the air hole 40 . The cooling air is excessive.
In the air conditioning installation 100 , the quantity of air from the air conditioner is decreased. Thus, the rack can be efficiently cooled by balancing the quantity of air to be used for cooling the rack and the supplied quantity of air from the air conditioner and hence by decreasing the waste of the cooling air from the air conditioner.
Further, in the air conditioning installation 100 according to the second embodiment, when the plurality of racks are provided, the average of the plurality of detected rack exhaustion temperatures are calculated, and the quantity of air from the air conditioner is controlled to decrease the difference between the averaged rack exhaustion temperature and the air conditioner return temperature. Accordingly, the waste of the cooling air from the air conditioner can be decreased, and hence the plurality of racks can be efficiently and properly cooled.
Third Embodiment
While the embodiments of the invention have been described above, the embodiments may be implemented in various forms other than those of the above-described embodiments. Hence, another embodiment included in the invention will be described below as a third embodiment.
(1) Local Air Conditioner
In the second embodiment, the quantity of air from the main air conditioner has been controlled. In this embodiment, it is not limited thereto. If a local air conditioner relatively smaller than the main air conditioner is installed, the quantity of air from the local air conditioner may be controlled.
In this embodiment, a configuration of an air conditioning installation 100 A according to the third embodiment will be described with reference to FIG. 5 as a case in which the quantity of air from a local air conditioner 2 A is controlled. FIG. 5 is a block diagram of the configuration of the air conditioning installation 100 A according to the third embodiment.
Referring to FIG. 5 , the air conditioning installation 100 A according to the third embodiment includes the local air conditioner 2 A installed above a rack. In addition, an exhaustion guide path 30 is provided below the local air conditioner 2 A. The exhaustion guide path 30 divides an aisle into a hot aisle and a cool aisle. The local air conditioner 2 A does not have to be provided above the rack, and may be provided near the position at which a hot spot is generated, so as to increase the cooling performance and air quantity. The processes carried out by the air conditioning control unit 10 and the temperature detectors 20 A to 20 D are similar to those in the second embodiment.
(2) System Configuration
The components of the illustrated devices and units represent concepts of functions. The components do not have to be physically arranged as illustrated. In particular, the specific forms of the devices and units in terms of division and combination are not limited to the illustrated forms. All the devices and units, or part of the devices and units may be functionally or physically divided into smaller devices and units, or combined to define larger devices and units by the desirable unit basis depending on various loads and use conditions to be considered. For example, the temperature judgment unit 10 a may be combined with the air quantity control unit 10 b . Further, all or part of the processing functions carried out by the devices and units may be attained by a CPU or a program that is analytically executed by the CPU. Alternatively, the processing functions may be attained by hardware based on a wired logic.
(3) Program
The processes of the air quantity control unit 5 described in the first embodiment may be attained by executing a predetermined program with a personal computer or a computer system such as a workstation. Now, an example of a computer that executes an air quantity control program 711 serving as an air conditioning control program having a function similar to the first embodiment will be described below with reference to FIG. 6 . FIG. 6 illustrates a computer 600 that executes the air quantity control program 611 .
Referring to FIG. 6 , the computer 600 serving as an air quantity control device includes a RAM 610 , a CPU 620 , a HDD 630 , and a temperature sensor 640 , which are connected with one another through a bus or the like.
The temperature sensor 640 detects a blow temperature of an air conditioner, a return temperature of the air conditioner, a introduction temperature of a rack, and an exhaustion temperature of the rack. The HDD 630 stores information for executing various processes by the CPU 620 . The RAM 610 temporarily stores various pieces of information. The CPU 620 executes various arithmetic processes.
Referring to FIG. 6 , the HDD 630 previously stores the air quantity control program 611 that provides functions similar to those of respective processing units of the air quantity control unit described in the second embodiment. The air quantity control program 611 may be divided, and stored in a storage portion of another computer that is connected to the computer 600 such that communication may be held therebetween through a network.
The CPU 620 reads the air quantity control program 611 from the HDD 630 , and develops the read air quantity control program 611 in the RAM 610 . The air quantity control program 611 reads the various data from the HDD 630 and develops the data in a region of the RAM 610 , the region which is allocated to the air quantity control program 611 . The various processes are executed on the basis of the developed data etc.
The air quantity control program 611 does not have to be previously stored in the HDD 630 . For example, programs may be stored in a “portable physical media” that is inserted into the computer 600 , such as, a flexible disk (FD), a CD-ROM, a DVD, a magneto-optical disk, or an IC card; or “another computer (or server)” that is connected with the computer 600 through a public line, the Internet, a LAN, or a WAN. The computer 600 may read the programs from such a media or computer and execute the programs.
The disclosed system efficiently and properly cools the rack by decreasing the waste of the cooling air from the air conditioner.
All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the invention. Although the embodiments of the present inventions have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention. | An installation for cooling an electronic device includes an air conditioner having an air outlet for blowing cooling air to a room; a first detector adjacent to the air outlet of the air conditioner, for detecting a temperature of the cooling air; a rack accommodating the electronic device, the rack having an air inlet for receiving the cooling air from the air conditioner and an air outlet for exhausting air to the room; a second detector adjacent to the air inlet of the rack, for detecting a temperature of air received through the air inlet of the rack; and a controller for acquiring the temperatures detected by the first and the second detectors, and controlling a quantity of the cooling air blown from the air outlet of the air conditioner so as to decrease a difference between the temperatures detected by the first and the second detectors. | 5 |
BACKGROUND OF THE INVENTION
The area of technical application of the invention is that of textile machines. In this area, the machine involved is in particular a draw frame with calendar equipment following the drafting equipment, consisting usually of two calendar disks facing each other by means of which the fiber sliver is compressed. Both are described in DE 295 10 871 U1 of Jul. 5, 1995. This patent refers to the full contents of this patent application.
As a rule several fiber slivers are doubled into one single fiber sliver before the drafting equipment. The doubled fiber sliver is conveyed into the drafting equipment. During the drafting process, the fiber sliver is spread out into a fiber fleece and is conveyed in this condition from by the pair of delivery rollers of the drafting equipment. The fiber fleece must be formed again into a fiber sliver. This is done by means of the fleece funnel. As the fiber fleece enters the inlet of the fleece funnel, a fiber sliver is formed again.
In the state of the art it is known that a pair of delivery rollers is provided at the output of drafting equipment of a draw-frame (e.g. a fiber processing machine) which conveys this fiber fleece into a fleece funnel. The fiber fleece is gathered together in the fleece funnel and is formed back into a fiber sliver and is conveyed to a fiber sliver channel having a considerable length. At the end of the fiber sliver channel, the fiber sliver is introduced into a fiber sliver funnel which deflects the direction of travel of the fiber sliver by approximately 90° and introduces it between a pair of calendar rollers (calendar disks). Once the fiber sliver has run through the pair of calendar rollers, the fiber sliver which has been compressed therein is conveyed on to the depositing device of the draw frame (see also e.g. EP 593 884 A1, U.S. Pat. No. 4,372,010 or DE-A 26 23 400).
In DD 290 679 the fleece funnel and the sliver funnel are at a considerable distance above a fiber sliver channel. A venting opening (13 therein) allows the air which flows in at the beginning of the collection channel (therein 5) to escape completely before the narrowest point of the sliver funnel in order to build up again a suction stream shortly thereafter which is built up with inflowing compressed air by an injection bore in the fleece channel segment with the smallest diameter.
OBJECTS AND SUMMARY OF THE INVENTION
The invention has as a principal object to bring the beginning of the fiber fleece automatically into the fiber sliver channel between the delivery rollers and the calendar disks and to deposit it directly in front of the nip of the calendar disks, in particular in a manner that is economical of the conveying air. Additional objects and advantages of the invention are set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.
The process according to the invention avoids lateral escape of an air stream which is conveyed in the lateral air-tight guiding channel through at least two nozzle segments of the fiber sliver guiding system. The conveying air which is conveyed free of loss is produced via injection bores which are provided in the cylindrical segment of the sliver funnel, shortly before the nip of the calendar disks, whereby the above-mentioned cylindrical segment merges into a pointed end of the sliver funnel which is located immediately before the nip. The diameter of the cylindrical segment is here considerably smaller than the width of the calendar disks which are calendaring the fiber sliver fed to them.
Hereinafter mention is made of a pair of calendar disks or of the calendar disks, and this term also covers a pair of calendar rollers. This is possible because the invention excludes neither a pair of calendar disks nor a pair of calendar rollers.
The diameter of the cylindrical segment may be less than one third of the width of the calendar disks or, expressed differently, the calendar disks are at least three times wider than the diameter of the narrowest segment of the sliver funnel.
The process functions with a closed nip as well as with an open nip.
In order to enable the sliver funnel and its guiding channel to be placed very close to the nip, the forward end tapers to a point and ends in a line; curved surface segments of the forward end of the sliver funnel which are adapted to the curvature of the surface of the calendar disks also end in this line. The pointed end can correspond to the width of the nip.
Faster and more reliable preparation is ensured through the invention due to the elimination of the long fiber sliver channel of the state of the art, so that the fleece funnel and sliver funnel can be installed directly one after the other. This is the guiding system.
It now becomes possible to accelerate and simplify preparation, i.e. the introduction of the drafted fiber sliver, and to reduce air losses as much as possible. Thanks to the elimination of the fiber sliver channel, the fiber sliver guiding system according to the invention becomes particularly short and compact. Long distances, and thereby technologically undesirable dead times, can be reduced. In spite of its compact construction, the fiber guiding system is easy to handle and even allows for two positions of the interlocking nozzles via the air-tight articulation, one for normal operation and one for preparation. Surprisingly, the compact fiber sliver guiding system can be adjusted easily and is maintenance and service friendly. In spite of the compact construction of the guiding system, it is possible to replace the nozzle inserts in order to make rapid change-over possible in case of a batch change.
The nearly totally loss-free air conveying process from fleece funnel to in front of the nip of the calendar disks is characteristic for the air-guided automatic introduction of the fiber fleece into the fiber sliver guiding channel of the textile machine. The air is conveyed without losses from the fleece funnel (which rolls together the drafted fiber fleece and gathers it) to the sliver funnel (which causes the fiber sliver to be compacted before the pair of calendar rollers). In this area, no lateral opening from which the air could escape is made in the guiding channel; in this area only lateral inflow bores (injection bores) which generate and maintain the air suction stream are present.
Because of the air conveying system which is closed up to the nip, the process for automatic introduction of the beginning of the fiber fleece is very economical in air. At the same time, the process is not sensitive to pressure fluctuations of the air used for the introduction and is able to work reliably within a wide range of compressed air.
Slanted introduction in the direction of fiber sliver movement causes the compressed air to become a suction stream on top.
Mechanical threading of a segment of the fiber fleece into the fleece funnel is entirely omitted. The fiber fleece merely has to be reduced to a smaller width at its forward end and the remaining, narrower segment has to be shortened to a predetermined length determined by the weight of the fiber fleece and the length of the fiber channel and the fleece channel from the fleece funnel to the nip. Brief actuation of a compressed-air generator in order to generate a brief compressed-air impulse produces the threading of the narrowed segment of fiber fleece into the fleece funnel and the conveying of this segment before the nip, where a brief rotational impulse of the calendar disks causes the complete threading or the complete introduction of the fiber sliver between the calendar disks.
The compressed-air impulse can be advantageously coupled with a rotational impulse that is slightly offset in time so that the operator needs to depress the push button only once in order to thread the fiber fleece. In the state of the art, a fiber fleece cannot be presented, introduced and be brought into operating position any more easily, rapidly and reliably.
The suction air stream above the point of compressed-air intake is reliably created when the compressed air is introduced at the point of the fiber sliver conveying channel with the smallest diameter. This is the sliver funnel which is installed in close proximity of the calendar disks. A stream of compressed air fed at this point in the direction of the calendar disks reliably produces a suction air stream above the feed point and going up to the fleece funnel, as no air losses occur there. No openings at a right angle to the guiding channel are provided in the entire guiding segment going from the fleece funnel to the sliver funnel which could make it possible for air to escape. The reliable build-up of the suction air stream starting at the forward end of the conveying path and taking effect back to the point of entry of the spread-out fiber fleece--the fleece funnel--makes it possible to avoid the necessity of bringing any additional air flow into this area, as is normally the case in the state of the art, when an inflow of air is provided at the fleece funnel or directly thereafter, while venting is provided at the sliver funnel or directly thereafter.
With the present invention the fiber fleece is thus taken up at its forward end by the air stream and is then pulled in the form of a fiber sliver along the entire fiber sliver channel and is presented directly in front of the calendar disks. The fiber sliver is not "pushed" by compressed air and is de-aired far before the calendar disks.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 shows the usual configuration of a fiber sliver guiding system with a long fiber sliver channel (left side of drawing) superimposed on a compact construction according to the invention (right side of drawing) with two nozzle inserts 30, 40, 50 60 connected together, of which two nozzle inserts 40, 50 are able to tilt relative to the other two nozzle inserts 30, 60 which are located on a nozzle holder 20 fixedly installed above the calendar disks 100a, 100b. The superimposed drawing serves to illustrate the shortening of the conveying distance. The deflection roller 71 is part of the compact construction shown on the right side of the drawing;
FIG. 2 shows a fiber sliver guiding system according to the state of the art;
FIG. 3 shows the preparation of the fiber fleece F for introduction into the fleece funnel 50;
FIGS. 4a, 4b and 4cshow an enlargement of the sliver funnel 30 of FIG. 1 which feeds the air without losses to a point directly at the nip 100a c;
FIGS. 5a and 5bshow the swiveling of a fleece funnel with nozzle insert 40' and a calendar disk 100b around a common pivot point SP.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Reference will now be made in detail to the presently preferred embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, and not meant as a limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the invention without departing from the scope or spirit of the invention.
The superimposition of FIG. 1 shows the difference with the state of the art which is shown schematically in FIG. 2. The fiber sliver FV which is not yet drafted when it is introduced in the state of the art via drafting rollers 68a, 68b, 69a, 69b and delivery rollers 70a, 70b by means of a fleece funnel 1 into a long guiding channel 8 which lets out in a sliver funnel 9. The sliver funnel deflects the fiber sliver FB by approximately 90° and into the nip of the calendar with its calendar disks 100a, 100b. The calendared fiber sliver KF emerges from the calendar in a vertically downward direction and is stored in a depositing device. This fiber sliver guidance is also shown with the same reference numbers in FIG. 1.
An embodiment of the invention shortens the fiber sliver path and makes it possible to omit the fiber sliver channel 8. An additional deflection roller 71 is used which deflects the direction of travel of the fleece FV by approximately 60° and introduces the fiber sliver into a device consisting of several functional elements forming the fiber sliver channel. The first element is the fleece funnel 50 with a ramp surface 50b and an immediately following funnel section 50a in which the wide, arriving fiber sliver (also called a fiber fleece) folded, doubled and is introduced into a first channel section. The channel section is constituted by an insert 40 which is plugged in on the rear side of the funnel segment 60 and is attached with a screw.
An articulation surface is provided at the forward end of insert 40 and, in the corner position shown in FIG. 1, it makes possible sealing off the guiding channel against the downstream sliver funnel 30.
The articulation surface of the forward, cylindrical segment of the inner insert 40 consists of two constantly curving surface segments tapering towards the rear which engage a matching bearing surface 35 on sliver funnel 30. Swiveling the fleece funnel 50 in direction α into the other end position does not break the radial air-tight seal between fleece funnel and sliver funnel, and air-tight air fiber sliver conveying is obtained in the closed as well as open, swiveled state.
The radial tightness on the articulation surfaces 35 is adjustable. The upper part--above the articulation surface--can be modified for this in axial direction, in particular also in radial direction in its relative position to the lower part. The fixed holder 20 in which the sliver funnel is inserted constitutes the basis for adjustment.
If the fleece funnel 50 is made in two parts--with the insert inserted into the funnel bore of the fleece funnel in a direction opposite to that of fiber sliver movement--the previously mentioned relative adjustment can be made on a grip 51.
The sliver funnel 30 is made in the form of an insert and reaches with a pointed tapered V-shaped end between the calendar disks 100a, 100b directly to the nip 100c. The insert 30 is configured so that it can be inserted axially into a sliver funnel holder 60 and be held there.
The fiber sliver is conveyed through the fleece nozzle 50, the inner insert 40 and the sliver funnel 30 into the guiding channel up to nip 100c, and for this the fleece 50 is swiveled out. The manually narrowed fiber fleece part F1 is held into the funnel opening 50a and is sucked in via injection bores 34a, 34b, 64a, 64b on the sliver funnel. A brief suction stream of a magnitude in time of approximately 500 m/sec is sufficient in order to convey the narrowed fiber sliver F1 with a minimal expenditure of compressed air until it is in front of the nip 100c, since the articulation bearing surface 35 and the bearing surface of the inner insert 40 are radially sealed off. Mechanical insertion assistance is not required.
In order to introduce first the segment F1 of the fiber fleece, and with it the full width F of the fiber fleece, through the nip in the form of an reshaped fiber sliver, a brief rotational impulse is imparted the calendar disk. It is able to shut itself off automatically after a predetermined suction time, may be superimposed on it, or can be shut off separately, manually.
The form of the sliver funnel 30 is clearly shown in FIG. 4a, and the direction and placement of the injection bores 34a, 34b in the sliver funnel are also shown in enlarged form here. The bores let out into a cylindrical channel 31 constituting the forward end of the fiber sliver channel. The cylindrical segment 31 widens over a conical segment 32 to the diameter of the fiber sliver channel which is determined by the inner insert 40.
The slanted injection bores 34a, 34b may form an angle of approximately 45° with the axis 200b of the sliver funnel insert 30, and they may be parallel-offset in order to impart a twist to the introduced fiber sliver as well as additional strength.
A sliver funnel holder 60 is provided with a centered, approximately cylindrical opening into which the sliver funnel insert 30 is inserted. An annular channel 33 open to the inside extends in circumferential direction in the cylindrical opening and can be supplied with compressed air by two or more cylindrical bores 64a, 64b. Extending from the annular channel, the compressed air introduced from the outside is introduced into the previously mentioned slanted injection bores 34a, 34b when the sliver funnel insert 30 is inserted and lets out in the cylindrical segment 31 of the fiber sliver channel which is located immediately against the nip 100c.
The forward end of insert 30 is V-shaped and has slightly curved V legs which are adapted to the surface curvature of the calendar rollers 100a, 100b. The sliver funnel insert 30 can thus be inserted directly into the slightly curved, narrowing intermediate space between the calendar disks and the cylindrical segment 31 ends with its forward end directly in front of the nip 100c. This becomes especially clear in the side view of FIG. 4c. The diameter d of the cylindrical guiding channel 31 is shown here. The forward, cylindrical segment of the sliver funnel insert 30 is provided here with two surface segments 31a, 31b which taper laterally in an upward direction and have the curvature shown in FIG. 4a. A V shaped opening end results in function of the pointed tapered sliver funnel insert 30 and the cylindrical bore 31 with constant diameter, whereby the air flowing through the injection bores emerges from this opening and conveys the fleece up to the nip.
Because of the width b of the calendar disks in relation to the clearly smaller diameter d of the cylinder guiding channel, the air cannot or only barely or slowly escapes laterally, so that the major portion of the flowing air is conveyed up to the nip and deposits the fiber fleece it carries along at that point.
FIG. 4b shows a top view in which the width b of the two calendar disks 100a, 100b can be seen. Also shown are the injection bores 64a, 64b as feed channels going to the annular channel 33, as well as the parallel-offset, slanted injection channels 34a, 34b in insert 30. At least 2 injection channels are present, so that the fiber sliver is centered and is at the same time imparted a twist.
The compressed air can be used at a pressure of 4 bar, for example, but is adapted to a channel diameter of approximately 3.8 mm in the sliver funnel and approximately 8 mm in the insert 40 of the fleece funnel 50. Tests have shown that even a compressed air blast of approximately 500 m/sec duration is sufficient for secure introduction of the forward end F1 of the fiber sliver up to the nip 100c. The length H1 of the manually narrowed fiber fleece is here adapted to the distance between the fleece funnel 50 and the nip 100c, and thereby to the length of the air-tight fiber sliver channel.
The above-mentioned annular channel 3 may also be made on the insert 30, e.g. by a surrounding notch, in an alternative variant (not shown in the drawings).
FIG. 5a shows a fleece funnel 50 with a nozzle insert 40'. The insert 40' is made in one piece. The insert 40' has a fiber sliver guiding system designed so that it corresponds in a first segment to the fiber guiding system of an insert 40 and in the following segment to the fiber sliver guiding system of a sliver funnel 30 (as in FIG. 4a). FIG. 5a shows such an insert 40' in preparation position, i.e. in a position for the presentation of the fiber fleece into the funnel area 50a. This position shown in FIG. 5a is also assumed by the insert 40' when a backup of fiber fleece has occurred.
The insert 40' can be replaced much quicker than the insert 40 and the sliver funnel 30 as shown in FIG. 1. Readjustment or alignment tasks can be omitted because of the compact (one-piece) configuration of the insert 40'. Furthermore no air-tight swiveling articulation is necessary.
In an advantageous embodiment, a calendar disk 100b and the insert 40' are located in a common support or holder (not shown). The support swivels around a pivot point SP. It is possible to swivel the calendar disk 100b and the insert 40' around the common pivot point SP. Since insert 40' is connected to the fleece funnel 50, both are therefore swiveled. For the sake of simplification only swiveling of insert 40' is mentioned hereinafter. Swiveling provides better access to the operator and allows him to see the insert 40' better. A conveyed fiber fleece can therefore be presented manually in the funnel area 50a in order to thread the beginning of the fiber fleece. The fiber fleece is formed by the fleece funnel into a fiber sliver and is immediately conveyed between the open calendar disks 100a, 100b. For the beginning of stationary operation the insert 40' and the calendar disks 100a, 100b are swiveled back into position as shown in FIG. 5b. This is the position for stationary operation (operating position) of insert 40'.
Another embodiment makes it possible to swivel insert 40' separately and to swivel the calendar disk 100b separately around pivot point SP. This allows the calendar disk 100b to remain in closed position during sliver introduction. Only the insert 40' swivels for the introduction of the sliver start. If it is necessary to open the calendar disks, this can be done separately.
It is also possible to have an embodiment in which the insert 40' does not swivel but is fixed as shown in FIG. 5b. In such a design, the guiding surface LF of the fleece funnel 50 must be pivotable. A pivot axis must be advantageously provided in the lower area of the guiding surface so that said guiding surface LF can be swiveled away only from the funnel area 50a. This makes it possible to swivel guiding surface LF away in case of fiber fleece back-up, so that said fleece is able to move out of the funnel area 50a. Furthermore, the operator is afforded a view of the funnel area 50 thanks to the ability of guiding surface LF to swivel. In this embodiment, a calendar disk 100 can furthermore be supported so as to be able to swivel relative to a pivot point SP.
It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope and spirit of the invention. For example, features illustrated or described as part of one embodiment may be used on another embodiment to yield a still further embodiment. It is intended that the present invention cover such modifications and variations as come within the scope of the appended claims and their equivalents. | A process and device are provided to introduce a fiber fleece through the nip of a pair of calendar rollers. Pressurized air is directed to a cylindrical segment of a sliver guiding system down stream from a tapered conical section so that the pressurized air draws the fiber fleece through the sliver guiding system without requiring lateral venting or expansion of the pressurized air. The pressurized air vents from the front end of the cylindrical section adjacent the nip of the pair of calendar rollers. | 3 |
This appln is a Divisional of Ser. No. 09/838,416 filed Apr. 19, 2001.
BACKGROUND OF THE INVENTION
The present invention relates to an electrical connecting element.
More particularly it relates to an electrical connecting element which can be connected to an electrically insulated end of a wire, wherein the end of the wire during connection of the connecting element is simultaneously bared and reliably mounted in the connecting element.
For connections of connecting elements, such as bushing or electrical plugs, to an electrical wire, conventionally the end of the wire is bared and then connected by means of a clamping or screw connection with a connecting element. There are however applications in which during the process of connection of a connecting element to a wire, the wire to be bared must not be contacted. This is the case for example in the medical field, when for example an external heart pacemaker must be connected to the conductors which are connected with the heart muscles and extend out of the body. In this case the conductors which extend out of the body must not be contacted with its conductive core. A contact of the conductive core of the wire can cause an electrical discharge. Such an electrical discharge can lead to grave heart rhythm distortions up to a heart chamber flicker. In this particular case the connecting element must be connected to the slotted and further electrically insulated end of the wire without removing the insulation of the wire.
So-called clamping plugs are known in the prior art in particular from the company Multi-Contact AG, Basel, Switzerland. In these clamping plugs the insulated wire is clamped in a plug and simultaneously the insulation is removed. These plugs are however relatively expensive, susceptible to failures, voluminous and difficult to operate, since they contain a spring element and a pressure button. Moreover, diverse plug elements for bared wires are known as well.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide an electrical connecting element for connection to an electrically insulated end of a wire, which avoids the disadvantages of the prior art.
More particularly, it is an object of present invention to provide an electrical connecting element for connection to an electrically insulated end of a wire, in which the wire before the connection must not be bared, which is easy to handle, and which has a small size and a simple construction.
In keeping with these objects and with others which will become apparent hereinafter, one feature of present invention resides, briefly stated, in an electrical connecting element having a clamping sleeve in which an end of the wire is insertable and clampable, and an insulation sleeve connected to the clamping sleeve and provided with a connecting contact, so that during connection of the clamping sleeve and the insulation sleeve, the connecting contact of the insulation sleeve is brought in contact with the end of the wire with maintaining of the insulation of the wire, and is held in this position.
When the electrical connecting element is designed in accordance with the present invention, it eliminates the disadvantages of the prior art and provides for the above mentioned advantages. The inventive electrical connecting element is composed of two parts including a so-called clamping sleeve and a so-called insulation sleeve which are connectable with one another. The electrically insulated end of the wire, to which the electrical connecting element must be connective, is first inserted in the clamping sleeve and then preliminarily clamped. For this purpose it can be inserted in a correspondingly formed passage of the clamping sleeve and firmly clamped there. Preferably, this passage is formed so that the end of the wire is inserted in a doubled force unloading loop and held in it.
The clamping sleeve and the insulation sleeve are formed so that, when they are connected with one another for example by screwing, the wire is clamped between them and its insulation eliminated, and a connection contact which is provided in the insulation sleeve is brought in electrical contact with the bared end of the wire.
For providing this clamping and simultaneous insulation removal of the wire end, the clamping sleeve has for example a recess with a diameter which expands toward the connection point. The recess is formed for example as a funnel. The end of the wire is inserted into the clamping sleeve preferably so far that the end of the wire is located substantially at the connecting point between the clamping sleeve and the insulation sleeve. The connecting contact of the insulation sleeve includes a forwardly reducing squeezing contact element, which is formed so that during connection of the clamping sleeve and the insulation sleeve it is forced into the recess of the clamping sleeve. Thereby the end of the wire located there is squeezed against the wall of the recess of the clamping sleeve.
The squeezing contact element can be formed in different ways with consideration of the above described deformation. It can be formed for example from the screw thread, from several disks arranged at a distance from one another and having a reducing diameter, or from several cylinders with a reducing diameter. It is important that during insertion of the squeezing contact element the end of the wire is not upset, but instead is reliably pressed against the wall of the recess of the clamping sleeve, and simultaneously the insulation is removed from the wire end. The outer edges of the squeezing contact element must be formed so sharp that they can remove the insulation of the wire end, but at the same time must not be too sharp that they can cut the wire strand. A further securing against separating of the wire strand is provided by a certain yieldability of the clamping sleeve material.
The connecting contact of the insulation sleeve, in addition to the squeezing contact element also advantageously has a connecting member which is electrically connected with the squeezing contact element. The connecting member can be formed for example as a plug pin or a plug bushing. A correspondingly shaped plug bushing or a plug pin can be connected with the thusly formed connecting member so that an electrical conductor and an electrical wire are connectable with the inventive connecting element. The plug pin or the plug bushing must be insulated from outside, so as to prevent the users contact with the bared wire.
Th clamping sleeve and the insulation sleeve can be connected with one another in a known manner. For example they can be provided for this purpose with matching screw threads or a connection device in form of bajonet lock or a louver lock connector.
The clamping sleeve and the insulation sleeve must be composed of an electrically insulating material. For this purpose for example an impact-resistant plastic which is not flowable at the corresponding application temperatures can be utilized. For the use in the medical field it is advantageous when a synthetic plastic or a similar material is selected so that, it can be easily sterilized for example in ethylenoxide. For preventing erosion in unfavorable application conditions and nevertheless maintaining a good electrical contact, it is advantageous when the electrically conductive parts, such as for example the connection contact of the insulation sleeve, are composed of non-corroding materials, for example high grade steel. Moreover, these materials can be coated, for example brass gilded, for improving the electrical contact.
In accordance with a further preferable embodiment of the present invention, in an electrical connecting element the clamping sleeve and the insulation sleeve can be secured by an arresting clamping from an inadvertent loosening, for example by screwing. The clamping sleeve can be provided with a projection near the outer thread on its outer side, which is insertable into a gap of the periphery of the arresting clamping ring, to produce an arresting connection between the clamping sleeve and the arresting clamping ring.
In accordance with a further preferable embodiment of the present invention, the arresting clamping ring during screwing of the clamping sleeve and the insulation sleeve with one another can overcome the projection by deformation when an arresting torque is exceeded. The projection is dimensioned so that during a further screwing of the both sleeves, it vanishes in the inner thread of the insulation sleeve and has no more alternating action with the arresting ring. The sleeves can be screwed without further resistance and the inserted wire is squeezed.
The insulation sleeve can be provided on its outer side with a peripheral bead and with at least one axially oriented web which forms an abutment for at least one arresting hook arranged on the inner side of the arresting clamping ring, when the clamping sleeve with the arresting clamping ring arrested with it is inserted into the insulation sleeve. The at least one arresting hook is non-releasably arrested over the peripheral bead and thereby prevents an unscrewing of the clamping sleeve and the insulation sleeve.
After mounting of the clamping sleeve and the insulation sleeve, the arresting clamping ring is used so that the insulation sleeve and the clamping sleeve no longer can turn relative to one another and therefore again release from one another. Preferably, the insulation sleeve have four axially oriented webs which form abutments for the four arresting hooks arranged on the clamping ring. Thereby it can be guaranteed that practically no rotary movement of the insulation sleeve relative to the clamping sleeve is possible.
The inventive electrical connecting element is easy to operate, it has a simple construction. It is small, it can be reliably mounted on a not insulated wire, and the user does not come into contact with the electrically conductive part of the wire, so that the inventive electrical connecting element is especially advantageous for use in the medical field, for example for connection of an external heart pace maker.
The novel features which are considered as characteristic for the present invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic exploded view of a cross-section of an electrical connecting element in accordance with the present invention;
FIG. 2 is a view showing the inventive connection element of FIG. 1 in an assembled condition;
FIG. 3 is a view showing another embodiment of a connecting contact of an insulation sleeve of the inventive connection element;
FIG. 4 is a view showing still a further embodiment of the connecting contact of the insulation sleeve of the inventive connection element;
FIG. 5 is a view showing an example of the application of the inventive electrical connection element for connection of a heart pacemaker;
FIG. 6 is a perspective exploded view of a further embodiment of a connection element;
FIG. 7 is a view showing a longitudinal section of the connection element of FIG. 6 in a screwed-on condition and during insertion of a wire; and
FIG. 8 is a view showing a longitudinal section through the connection element of FIG. 6 in the screwed-on condition after the mounting on the wire.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows schematically a cross-section of an inventive electrical connection element. For clear understanding of the individual elements of the connection element, they are shown on an exploded view. The electrical connection element in accordance with the present invention includes two parts, namely a clamping sleeve 10 and an insulation sleeve 20 . An end of a wire 30 which must be connected to the connection element is inserted in the clamping sleeve. For this purpose the clamping sleeve 10 has an opening in which the wire 30 can be inserted. In the shown embodiment the opening is composed of a passage 12 and a funnel-shaped inlet 14 , via which the wire 30 formed as a force unloading loop can be inserted. The clamping sleeve 10 has an expanding opening 16 at its end which faces the insulation sleeve 20 . It is funnel-shaped also. The wire 30 later is firmly clamped in the opening 16 . The wire 30 for this purpose must be inserted into the clamping sleeve 10 so that its end ends substantially at the end of the recess 16 .
A squeezing contact element 22 of a connection contact 21 of the insulation sleeve 20 engages in the recess 16 of the clamping sleeve 10 when the clamping sleeve 10 and the insulation sleeve 20 are connected with one another. It clamps the end of the wire 30 , as can be seen better from FIG. 2 . The squeezing contact element 22 for this purpose has a shape with a forwardly reduced diameter, which is provided with edges. The squeezing contact element 22 in the shown embodiment is formed as a screw.
The connecting contact 21 of the insulation sleeve 20 additionally has a connection member 23 which is electrically connected with the squeezing contact element. The connection member 23 is formed here as a plug pin. A not shown plug bushing can be connected with the plug pin so as to connect the inventive connection element with further electrical wires, which can be used for example for connection of an external heart pacemaker. For preventing contact of the user with the electrical wire, the connection member 23 is preferably insulated from outside. The plug pin which serves here as the connection member 23 is simply guided in an outer sleeve 24 .
The clamping sleeve 10 and the insulation sleeve 20 must be connected with one another. For this purpose the clamping sleeve 10 is provided with an outer thread 18 , while the insulation sleeve 20 is provided with an inner thread 25 , so that the both sleeves can be screwed with one another. Naturally other connections are also possible, such as for example a bajonet lock or an arresting connection.
FIG. 2 schematically shows a cross-section of the connection element of the present invention shown in FIG. 1, in an assembled condition. The clamping sleeve 10 and the insulation sleeve 20 are here screwed with one another and thereby connected with one another. It can be seen that the end of the wire 30 is squeezed between the squeezing contact element 22 and the wall of the recess 16 . The edges of the squeezing contact element 22 here the outer edges of the screw, displace simultaneously the insulation of the wire 30 , so that an electrical contact between the wire 30 and the squeezing contact element 22 is produced, and the electrical wire 30 simultaneous is firmly held between the squeezing contact element 22 and the wall of the recess 16 . At the right end of the insulation sleeve 20 , it can be seen that the connection member 23 which is formed as a plug pin is located in its sleeve 24 .
FIG. 3 shows another embodiment of the connecting contact 21 of the insulation sleeve 20 . The squeezing contact element 22 of the connecting contact 21 is composed here of several disks 26 which are arranged at distances from one another. They have a diameter which reduces forwardly.
FIG. 4 shows still a further embodiment of the connecting contact 21 of the insulation 20 . The squeezing contact element 22 of the connecting contact is composed of several cylinders 27 which are arranged one behind the other. The diameters of the cylinders 27 also reduce forwardly.
FIG. 5 finally shows the use of the inventive connection element for connection of an external heart pacemaker 40 to a heart wire, or in other words a wire 50 which is connected with the heart muscle 52 and extends outwardly beyond the body. The wire 50 is formed as a lead pair. The external heart pacemaker 40 has two connecting conductors 42 which are provided at their ends with plugs 44 . The plugs are connected correspondingly with the connecting conductors 42 of both electrical connection elements 64 formed in accordance with the present invention. The upper inventive connection element 60 is shown in a disconnected position and a lower inventive connection element 60 is shown in the connected position.
FIG. 6 shows the details of a further connection element in accordance with the present invention. All parts, with the exception of the connecting contact 22 , are composed of a synthetic plastic, for example transparent heart polyvinyl chloride, polycarbonate, acrylonitrile butadiene styrene. Alternatively to the sleeve 24 of FIG. 4, here a contact protective cap 80 is provided for the connecting contact 21 . For avoiding its loss it is connected via a connecting web 82 with a holding ring 81 . For improved frictional clamping on the connecting contact 21 , the contact protective cap 80 is composed of a soft material, such as for example PE or PP. When the connection element is used for connection to an external heart pacemaker, the protective cap 80 for marking the implantation position of a pacemaker electrode 30 can be colored to be recognized by the user. The holding ring 81 is displaced into the parts 10 over the outer surface of the funnel-shaped recess 16 for safety reasons. A projection 19 formed as a raised cylinder sector before the outer thread 18 is also provided on this outer surface. The height of the projection 19 is dimensioned so that, it corresponds to the radial thread gap between the outer thread 18 and the inner thread 25 shown in FIG. 7 . Thereby the later screwing mounting is not negatively affected. The peripheral width of the projection 19 corresponds to the width of the gap 72 of an arresting clamping ring 70 for securing the parts 10 and 20 .
In order to assemble the connection element shown in FIGS. 7 and 8, first the clamping ring 70 is clipped on the outer surface of the recess 16 . The projection 19 must be located in the gap 72 . After the insertion of the connecting contact 21 into the insulation sleeve 20 , the outer thread 18 is screwed into the first thread turn of the inner thread 25 . Thereby the arresting hook 71 of the arresting clamping ring 70 engages over a peripheral bead 32 of the insulation sleeve 20 . It can be located between axial webs 28 on the outer surface of the sleeve 20 . The arresting clamping ring 70 prevents in this way an inadvertent unscrewing of the parts 10 and 22 . The axial web 28 prevents via the arresting hook 71 a turning of the arresting clamping ring 70 . After the displacement of the contact protective cap 80 on the connecting contact 21 , the connection element is in condition ready to use, as shown in FIG. 7 .
FIG. 7 also shows how a user displaces a wire, for example the extracarporeal end of an implanted heart pacemaker electrode 30 , through the funnel-shaped inlet 14 on an insertion cone 29 of the connecting contact 21 along an insertion path 31 . The projection 19 of the part 10 is urged in the gap 72 of the arresting clamping ring 70 as shown in FIG. 6 because of the and provides the rotation safety of the arresting clamping ring 70 for an easy screwing safety of the total configuration of the connecting plug. With this screwing safety it is guaranteed that the user after unpacking of the element always holds the connection element in its hands in screwed-on, assembled, mounting-ready condition. After the insertion of the wire 30 or the heart pacemaker electrode, with a force screwing of the both parts 10 and 20 , the fixation by the projection 19 and the gap 72 is overcome, and finally the wire 30 is clamped and bared between the funnel-shaped recess 16 and the squeezing contact element 22 as shown in FIG. 6 .
FIG. 8 shows the connected, operation-ready connection element. Before the insertion in a temporary heart pacemaker machine shown in FIG. 5, the contact protective cap 80 must be withdrawn from the connecting contact 21 . In the embodiment of a connection element with a fixed sleeve 24 for contact projection shown in FIG. 1 and the available corresponding safety bushings on the temporary heart pacemaker, the contact protective cap 80 can be dispensed with.
It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions differing from the types described above.
While the invention has been illustrated and described as embodied in electrical connecting element, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.
Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention. | An electrical connection element for connecting an electrically insulated end of a wire has a clamping sleeve in which an end of a wire is insertable and clampable, an insulation sleeve connectable with the clamping sleeve and provided with a connecting contact arranged so that, during a connection of the clamping sleeve with the insulation sleeve the connecting contact of the insulation sleeve is brought into contact with an end of a wire with removal of an insulation of the wire, and is then held there. | 8 |
[0001] This application is a continuation which claims the benefit of U.S. application Ser. No. 14/506,081 filed Oct. 3, 2014, which is a continuation of U.S. application Ser. No. 14/262,165 filed Apr. 25, 2014, now U.S. Pat. No. 8,894,978, which is a continuation of U.S. application Ser. No. 13/310,455 filed Dec. 2, 2011, now U.S. Pat. No. 8,747,817, which claims priority to Provisional Application No. 61/418,940, filed Dec. 2, 2010, all of which are incorporated by reference herein.
BACKGROUND
[0002] The present invention relates generally to skin care and cosmetic compositions therefor, and more particularly to systems of complementary skin care products designed specifically for children.
[0003] Skin damage accumulates over a lifetime, beginning during infancy and building over childhood and adulthood until the cumulative effects result in serious diseases and disorders like skin cancer and/or serious aesthetic and functional damage to the skin. The main effect of sun damage and neglect, other than hyper-pigmentation and cancer, is to seriously degrade a person's appearance over time.
[0004] Children's skin differs from that of adults and changes over the course of childhood. Infant skin is softer and more prone to irritation and loss of moisture, while older children are prone to acne. It is difficult to get children to follow personal care regimens. Children may not like the appearance, smell, etc. of adult products, which also may not be properly formulated for children and can be harmful to them. Children may lack the motor skill or motivation to follow more complex or time-consuming care regimens.
[0005] Needs exist for improved skin care formulations, systems, and methods.
SUMMARY
[0006] It is to be understood that both the following summary and the detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. Neither the summary nor the description that follows is intended to define or limit the scope of the invention to the particular features mentioned in the summary or in the description.
[0007] In certain embodiments, the disclosed embodiments may include one or more of the features described herein.
[0008] A new skincare system and method utilizes complementary day and night skin cream formulations designed specifically for use by children ages six months to eighteen years. The complementary creams work together to produce a result greater than would be achieved by using either one separately or in conjunction with different products. The creams are formulated without harsh chemicals that could be damaging to the skin of young children and with largely natural ingredients. They and their packaging are designed to have an appearance, feel and scent that is attractive to children across a wide age range and are designed for a simple method of use that works within the existing personal care habits of children. The use of this system and method prevents the accumulation of skin damage over childhood, greatly improving the health and appearance of the skin over the user's lifetime.
[0009] A new system includes day and night skin cream compositions comprising nutrients and antioxidants for use by children between six months and eighteen years of age. The day skin cream composition provides protection from UV radiation and the night skin cream composition contains no sun protection ingredients and elevated levels of nutrients and antioxidants.
[0010] In one embodiment, there is a child-friendly bottle for each composition that can be used by young children without difficulty, both compositions include deionized water, capric triglyceride, shea butter, sunflower seed oil, vegetable glycerin, borage seed oil, cetearyl alcohol and glucoside, glyceryl stearate, xanthan gum, benzyl alcohol, fragrance, Vitamin E, aloe vera barbadensis leaf juice, and blueberry extract, the day composition also includes zinc oxide and T-lite SF-S and has an SPF of at least 20, and the nighttime composition also includes stearic acid. The fragrance is popular with children, and the bottle for the day composition has graphics indicating day-time use and the bottle for the night composition has graphics indicating night-time use.
[0011] In a new method of using the new system, the day composition is applied topically in the morning and the night composition is applied topically at night. In one embodiment, the day composition is applied topically each day to the face after tooth-brushing, and the night composition is applied topically to the face each night after tooth-brushing.
[0012] These and other objectives and features of the invention are apparent in the disclosure, which includes the above and ongoing written specification.
DETAILED DESCRIPTION
[0013] A complementary day/night skin cream system formulation and method will now be disclosed in terms of various exemplary embodiments. This specification discloses one or more embodiments that incorporate features of the invention. The embodiment(s) described, and references in the specification to “one embodiment”, “an embodiment”, “an example embodiment”, etc., indicate that the embodiment(s) described may include a particular feature, structure, or characteristic. Such phrases are not necessarily referring to the same embodiment. When a particular feature, structure, or characteristic is described in connection with an embodiment, persons skilled in the art may effect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.
[0014] Skin is the largest organ of the human body and plays a vital role in preventing infection, protecting the body from radiation, physical trauma, and other environmental hazards, and otherwise maintaining the health of an individual. Of course, skin also presents the outward appearance of a person, and as such is critical to others' perceptions of a person as youthful, beautiful, etc.
[0015] The skin protects the rest of the human body by shielding it and absorbing the damaging effects of physical and environmental trauma. As such, over time the skin tends to accumulate damage and to degrade, as well as to naturally age, developing wrinkles, unattractive marks including scars, blemishes, and hyper-pigmentation, and potentially cancerous cells, and losing elasticity and moisture.
[0016] However, skin health can be maintained in part by application of appropriate topical compositions, including moisturizers and nutrients, which are absorbed into the skin, as well as by proper diet and exercise. Sunscreens help to prevent sun damage, a major cause of skin deterioration. While skin heath tends to be of greatest concern to aging people and to women, in fact skin health is of great importance to people of all ages and races and to both men and women. The accumulation of skin damage begins in childhood. Therefore, to best maintain healthy skin over a lifetime, skin maintenance should begin during childhood.
[0017] A new skin care system and method uses daytime and nighttime formulations and is designed for children from 6 months to 18 years of age, for daily and nightly use to protect the skin from sun damage and maintain skin health. In specific embodiments, the daytime formulation is SPF 21.33 and also includes ingredients to nourish the skin and the nighttime formulation has extra antioxidants to overnourish the skin. The formulations have a consistency, feel, and smell that children like. Daytime formulation ingredients include deionized water, capric triglyceride, shea butter, sunflower seed oil, vegetable glycerin, borage seed oil, cetearyl alcohol and glucoside, glyceryl stearate, xanthan gum, benzyl alcohol, fragrance, Vitamin E, aloe vera barbadensis leaf juice, blueberry extract, zinc oxide, and T-lite SF-S. Nighttime formulation ingredients include the same, with the exception of z-cote and T-lite SF-S (sunscreen ingredients) and the addition of stearic acid, although in differing concentrations. In some embodiments, the nighttime formulation also includes sweet almond oil, cucumber extract, and acai berry extract. In some embodiments, the nighttime formulation also includes coffee bean extract.
[0018] This system starts with children at a young age and teaches them how to take care of their skin and the importance of skin health. Instead of trying to undo the effects of age and sun damage after they have occurred, this system slows the skin's aging process and prevents environmental damage from occurring in the first place. The two-step system of complementary day and night formulations ensures that the optimal formulation is being used at all times. The daytime formulation has SPF factors as well as other skin nutrients, but the nighttime formulation has a much stronger concentration of antioxidants and moisturizers, and does not have the SPF ingredients.
[0019] Typically, sunscreen is applied only during high sun activities such as the beach, pool, etc. While some cosmetics include some SPF protection, generally males do not use such products, and neither do children. Sun damage accumulates on a daily basis from everyday activities like driving or riding in a car, walking to school or to lunch, playing outside, such as at recess, etc. This is when the majority of sun exposure and sun damage occurs.
[0020] In this new daily skin care regimen, the day/night system is applied in the morning before leaving the house and at night when the sun is down and/or the child will not be leaving the house. The formulations are applied topically to the user's face, which is rarely covered by clothing and typically accumulates the most damage, yet is also the most critical to appearance. The formulations may also be applied to other vulnerable areas, such as the backs of the hands or forearms. The day formulation includes SPF for protection against sun damage, while the night formula does not, instead having a stronger concentration of nutrients. Nutrients such as vitamins and antioxidants improve overall skin health and help prevent or repair damage from the sun and from free radicals, maintaining skin elasticity and preventing the development of lines and wrinkles.
[0021] The system makes sense and is extremely practical. The high-antioxidant night crème can be applied by a child in approximately 10 seconds after they brush their teeth at night, and the moderate-SPF day formulation can be applied in the morning after they brush. This provides great skin nourishment and protection to give the user more beautiful skin and protect against one of the fastest occurring cancers today, skin cancer.
[0022] This first daily skin care regimen for children protects, hydrates, and helps prevent skin damage and premature aging. After years of research and development, the formulations have been optimized to provide the very best skin care for youths of all ages. The system delivers protection, hydration, and prevention (PHP) in one simple process utilizing the very best ingredients.
[0023] In certain embodiments, various features of the formulations ensure their attractiveness to children. Scents which have been shown in testing to be popular scents with children are applied to the formulations to ensure that a majority of children like the scent, which is an important factor in getting children to use a product, much more so than for adults. For the nighttime formula graphics of moons and stars are attractive and provide an immediate indication that the product is for bedtime use. For the daytime formula, graphics of the sun provide an immediate indication that the daytime formula is to be used at the start of each day. The bottles are kid-friendly for easy self-application.
[0024] Because application is incorporated into existing morning/bedtime routines, the system becomes part of a child's way of life. Parents can educate their children on the importance of protecting their skin similarly to the importance of brushing their teeth at night before bedtime and when they awake. Establishing a habit of use is very important to delivering PHP for children.
[0025] Due to the complementary nature of the night and day creams, the night cream typically has substantially more water, more antioxidants and nutrients and less skin conditioning agents than the day cream, and unlike the day cream will have no sunscreen ingredients. It also typically requires a higher level of emulsifiers and the like for maintaining the product in solution in a desired texture and appearance. In certain embodiments, the day cream may have about 60% by weight water, about 30-35% skin conditioning agents, about 6% sunscreen ingredients, and less than 0.5% of antioxidant and nutrient-rich ingredients, all by weight. In contrast, the night cream may have about 75% water, 15-20% skin conditioning agents, and about 0.4% to 1% antioxidant and nutrient rich ingredients and no sunscreen ingredients. In certain embodiments, the day cream may have 50-65% water, 20-40% skin conditioning agents, 5-10% sunscreen ingredients, and less than 0.5% antioxidant and nutrient-rich ingredients, while the night cream may have 65-80% water, 10-20% skin conditioning agents, and 0.3 to 1.5% antioxidant and nutrient-rich ingredients. The pH of the night cream may be about 2.5 below that of the day cream. The pH of the day cream may in some embodiments be 7-8 and the pH of the night cream may be 4.5-5.5. The pH of the day cream may be in some embodiments 6.5-8.5 and the pH of the night cream may be 4-6.5.
[0026] Vitamin E, blueberry extract, and acai berry extract can generally be considered antioxidant and nutrient-rich ingredients, while cetearyl alcohol, stearate, xanthan gum, DHA and benzyl alcohol are emulsifiers, surfactants, or preservatives. Capric triglyceride, shea butter, sunflower seed oil, vegetable glycerol, borage seed oil, vitamin E, aloe barbadensis leaf juice, cucumber extract and sweet almond oil are skin conditioners.
Exemplary Formulations & Batching
Day Cream:
[0027]
[0000]
Phase
Ingredient
% by WT
A
Deionized water
58.5500
B
Caprylic/Capric Triglyceride
15.0000
B
Shea Butter
0.5000
B
Sunflower Seed Oil
8.0000
A
Vegetable Glycerin 99.7% USP
6.0000
B
Borage Seed Oil
2.5000
B
Cetearyl Alcohol and Cetearyl Glucoside
0.5000
B
Glyceryl Stearate
0.5000
C
Xanthan Gum
0.5000
D
Benzyl Alcohol/DHA
1.0000
D
Fragrance (Bell-Aire #40534)
0.5000
D
Tocopheryl Acetate (Vitamin E)
0.1500
D
Aloe Vera Barbadensis Leaf Juice
0.1500
D
Blueberry Extract
0.1500
B
Z-Cote (Zinc Oxide)
3.0000
B
T-Lite SF-S (Titanium Dioxide, Hydrated Silica,
3.0000
Dimethicone/Methicone Copolymer and
Almuinum Hydroxide
[0028] Capric triglyceride is an oily liquid made from coconut oil that slows loss of water from the skin by forming a barrier on the skin's surface and alters the thickness of the solution. Shea butter, derived from the sheatree, is a skin conditioning agent and viscosity increasing agent that enhances the appearance of dry or damaged skin by reducing flaking and restoring suppleness and that slows the loss of water from the skin. Sunflower seed oil is a skin conditioning agent that enhances the appearance of dry or damaged skin by reducing flaking and restoring suppleness and that slows the loss of water from the skin. Vegetable glycerol is a sugar alcohol that increases the water content of the top layers of skin by drawing moisture from the surrounding air, and is also a skin protectant and viscosity decreasing agent. Borage seed oil is a plant seed oil that restores moisture and smoothness to dry and damaged skin and reduces inflammation. Cetearyl alcohol and cetearyl glucoside keep an emulsion from separating into its oil and liquid components. Glyceryl stearate acts as a lubricant on the skin's surface, giving the skin a soft and smooth appearance and slowing the loss of water from the skin by forming a barrier. It helps to form emulsions by reducing the surface tension of the substances that are emulsified. Xanthan gum is a binder, emulsion stabilizer, and surfactant and increases viscosity. Benzyl alcohol is a solvent, preservative, and viscosity decreasing agent. DHA is a preservative. Vitamin E is an antioxidant and helps to enhance the appearance of dry or damaged skin by reducing flaking and restoring suppleness. Aloe barbadensis leaf juice helps to enhance the appearance of dry or damaged skin by reducing flaking and restoring suppleness. Blueberry fruit extract contains many antioxidants and nutrients.
Batching:
[0029] 1) Combine phase A and B separately while mixing and heat to 80-85° C.
2) When the oil phase (B) is totally melted, ensure that Z-Cote and T-Lite SF-S is mixed in. Then sprinkle Xanthan Gum (phase C) into the oil phase. 3) Then add Phase A into Phase B/C. Continue to keep the temperature at 85° C. 4) Add back the water (q.s. to 100% by weight to replace water loss from heat) 5) Then homogenize the batch with the homogenizer (lab scale is approx. 3-5 minutes) 6) Switch back to mixing speed at low-medium speed 7) Turn heat off and continue mixing until it cools to 45-50° C. 8) Add Phase D (preservative and Aloe Vera juice) 9) Continue to mix until the batch is homogenous and temperature reaches 35-40° C. Stop mixer and evaluate.
[0038] The resulting product is an opaque emulsified lotion having a pH of 7.00-8.00, % solids of 38.4-42.4% (105 C, 1 hr), viscosity of 9,000-17,000 cps, and specific gravity of 0.940-1.040 gm/ml.
[0039] The most important aspect of the day cream is SPF protection. Sun damage is the single largest cause of skin cancer and of deleterious changes to skin appearance and most children are exposed to the sun daily when playing outside, being driven to activities, etc. The most sun damage accumulates in the face, where appearance is most important. This day cream is formulated to complement a night cream that over-nourishes the skin with large amounts of antioxidants and a low pH over night, freeing the day cream to contain high levels of sunscreen ingredients and resulting in a high SPF while maintaining a desirable appearance and texture and moisturizing properties.
Night Cream:
[0040]
[0000]
Phase
Ingredient
% by WT
A
Deionized water
76.5
B
Caprylic/Capric Triglyceride
4.5000
B
Shea Butter
0.7500
B
Sunflower Seed Oil
3.5000
B
Stearic acid
2.0000
A
Vegetable Glycerin 99.7% USP
4.0000
B
Borage Seed Oil
2.5000
B
Cetearyl Alcohol and Cetearyl Glucoside
2.0000
B
Glyceryl Stearate
1.5000
C
Xanthan Gum
0.9000
E
Benzyl Alcohol/DHA
0.5000
D
Fragrance (Bell-Aire #40534)
0.5000
D
Tocopheryl Acetate (Vitamin E)
0.1000
D
Aloe Vera Barbadensis Leaf Juice
0.1500
D
Blueberry Extract
0.1500
D
Sweet Almond Oil
0.1500
D
Cucumber Melon Extract
0.1500
D
Acai Berry Extract
0.1500
[0041] Stearic acid is a surfactant cleansing and emulsifying agent that cleans skin by helping water mix with oil and dirt so that they can be rinsed away and that helps to form emulsions by reducing surface tension. Cucumber melon extract is a skin conditioning agent that acts as a lubricant on the skin surface and gives the skin a soft and smooth appearance and enhances the appearance of dry or damaged skin by reducing flaking and restoring suppleness. Sweet almond oil acts as a lubricant on the skin surface, giving the skin a soft and smooth appearance. Acai berry extract contains a high level of antioxidants and nutrients.
Batching:
[0000]
1) Add water and glycerin into main beaker. Turn mixer on until a vortex forms.
2) Sprinkle xanthan gum into the vortex. Increase the mixing speed as xanthan gum goes into solution.
3) Continue mixing until xanthan gum is free of clumps and homogenous
4) While mixing, in a separate beaker, add all the content of Phase B (oil phase)
5) Turn heat on and heat both phases up to 60-65° C.
6) Pour the content of oil phase (phase B) into phase A (main beaker)
7) Turn heat off and continue mixing until the main batch cools down to 40-45° C.
8) Then add the content of Phase D. Continue mixing.
9) Then add Phase E, preservative. Continue mixing for approx. 30 minutes or until the batch is homogenous. Stop mixer and take a sample for analysis.
[0051] The resulting product is an opaque emulsified lotion having a pH of 4.5-5.5, % solids of 20.7-22.9% (105 C, 1 hr), viscosity of 9,800-18,000 cps, and specific gravity of 0.910-1.000 gm/ml.
[0052] The night cream over-nourishes the skin with a high concentration of antioxidants and natural nutrients and moisturizes the skin overnight when the body tends to become dehydrated. Because it is for night use only, sunblock does not need to be included, and absorption of antioxidants and nutrients is greatest at night where the ingredients are less prone to deterioration due to exposure to the sun and the elements. Because it is designed to be used with a day cream having a high SPF and neutral pH, but lower levels of antioxidants, the night cream does not need high levels of ingredients to repair sun-damaged or very dry skin, but does need to supply a high level of antioxidants to provide extended protection for the user and has a low pH to rebuild and maintain the user's acid mantle (acidic layer) to protect against acne and other infections. Younger children may not have an acid mantle, and this low pH will help to counteract their greater susceptibility to infection. The cream also maintains the skin's proper moisture level.
[0053] The invention is not limited to the particular embodiments described above in detail. Those skilled in the art will recognize that other arrangements could be devised, for example, using various concentrations of the ingredients and using various ingredient substitutions, subtractions, or additions to achieve varying textures, etc. While the invention has been described with reference to specific illustrative embodiments, modifications and variations of the invention may be constructed without departing from the scope of the invention. | A new skin care system includes day and night skin cream compositions comprising nutrients and antioxidants for use by children between six months and eighteen years of age. The day skin cream composition provides protection from UV radiation and the night skin cream composition contains no sun protection ingredients and elevated levels of nutrients and antioxidants. A child-friendly bottle for each composition can be used by young children without difficulty. A fragrance included in each composition is popular with children, and the bottle for the day composition has graphics indicating day-time use and the bottle for the night composition has graphics indicating night-time use. The day composition is applied topically each day to the face after tooth-brushing, and the night composition is applied topically to the face each night after tooth-brushing. | 1 |
[0001] This application claims the benefit of U.S. Provisional Application No. 60/353323, filed Jan. 30, 2002.
FIELD OF THE INVENTION
[0002] The present invention relates to processes and systems for liquefying natural gas. In one aspect the invention relates to such processes and systems wherein common compression string(s) are used to compress and recycle the refrigerants used in a plurality of individual trains which, in turn, are used for liquefying natural gas.
BACKGROUND OF THE INVENTION
[0003] Various terms are defined in the following specification. For convenience, a Glossary of terms is provided herein, immediately preceding the claims.
[0004] Large volumes of natural gas (i.e. primarily methane) are located in remote areas of the world. This gas has significant value if it can be economically transported to market. Where the gas reserves are located in reasonable proximity to a market and the terrain between the two locations permits, the gas is typically produced and then transported to market through submerged and/or land-based pipelines. However, when gas is produced in locations where laying a pipeline is infeasible or economically prohibitive, other techniques must be used for getting this gas to market.
[0005] A commonly used technique for non-pipeline transport of gas involves liquefying the gas at or near the production site and then transporting the liquefied natural gas to market in specially-designed storage tanks aboard transport vessels. The natural gas is cooled and condensed to a liquid state to produce liquefied natural gas at substantially atmospheric pressure and at temperatures of about −162° C. (−260° F.) (“LNG”), thereby significantly increasing the amount of gas which can be stored in a particular storage tank. Once an LNG transport vessel reaches its destination, the LNG is typically off-loaded into other storage tanks from which the LNG can then be revaporized as needed and transported as a gas to end users through pipelines or the like.
[0006] As will be understood by those skilled in the art, plants used to liquefy natural gas are typically built in stages as the supply of feed gas, i.e. natural gas, and the quantity of gas contracted for sale, increase. Each stage normally consists of a separate, stand-alone unit, commonly called a train, which, in turn, is comprised of all of the individual components necessary to liquefy a stream of feed gas into LNG and send it on to storage. As used hereinafter, the term “stand-alone train” means a unit comprised of all of the individual components necessary to liquefy a stream of feed gas into LNG and send it on to storage. As the supply of feed gas to the plant exceeds the capacity of one stand-alone train, additional stand-alone trains are installed in the plant, as needed, to handle increasing LNG production.
[0007] In typical LNG plants, each stand-alone train includes at least a cryogenic heat exchange system for cooling the gas to a cryogenic temperature, a separator (i.e. a “flash tank”), a “reject gas” heat exchanger, and a fuel gas compressor. As used herein, a “cryogenic temperature” includes any temperature of about −40° C. (−40° F.) and lower. LNG is typically stored at substantially atmospheric pressure and at temperatures of about −162° C. (−260° F.). To reduce the pressure of feed gas during liquefaction, it is typically passed from the cryogenic heat exchange system across an expansion valve or hydraulic turbine in a stand-alone train (i.e. “flashed”) before it is passed into the separator (i.e. the flash tank). As the pressure of the cooled feed gas is reduced to produce LNG, some of the gas flashes and becomes vapor. LNG is removed from the flash tank and is pumped from its respective stand-alone train on to a storage tank for further handling.
[0008] In somewhat greater detail, each stand-alone train is comprised of a cryogenic heat exchange system which, in turn, utilizes two or more refrigerant circuits, acting in series, to cool the feed gas down to the cryogenic temperature needed for liquefaction. Typically, the first circuit carries a first refrigerant (e.g. propane) which is compressed by a first compression string in the stand-alone train and is circulated through a series of primary heat exchangers to heat exchange with and initially cool the feed gas. Typically, the second refrigerant circuit carries a second refrigerant, e.g., a mixed refrigerant “MR” (e.g. nitrogen, methane, ethane, and propane) which is compressed by a second compression string in the stand-alone train and is circulated first through a series of propane heat exchangers and then through a main cryogenic heat exchanger to thereby complete the cooling of the feed gas to produce the LNG. In some cases, the cryogenic heat exchange system utilizes a cascade refrigeration system, a dual mixed refrigerant system, or some other refrigeration system, as will be familiar to those skilled in the art.
[0009] In some cases, the economics of an LNG plant may be improved by driving the compressors in both the first and second compression strings through one or more common shafts. However, this does not overcome all of the disadvantages associated with each stand-alone train in an LNG plant requiring its own dedicated, compression strings. For example, a complete stand-alone train, including two or more compression strings, must be installed in a plant each time it becomes desirable to expand the LNG plant production capacity, which can add significantly to the capital and operating costs of the plant. Further, if any refrigerant compressor, or its driver (e.g., a gas turbine) fails, in a particular stand-alone train, the affected stand-alone train must be shut down until the failed compressor and/or driver can be repaired. LNG production at the plant is significantly reduced during the down time. Still further, anytime a stand-alone train is shut down due to failure of a compression string, the temperature in the main cryogenic heat exchanger of that stand-alone train will rise substantially thereby requiring “recooling” of the main heat exchanger to the cryogenic temperature before the train can be put back into production.
[0010] It is desirable to improve processes and systems for liquefying natural gas to lower the costs of LNG production as much as possible so that LNG can continue to be delivered to market at a competitive price.
SUMMARY OF THE INVENTION
[0011] The present invention provides natural gas liquefaction systems and processes wherein a first refrigerant and a second refrigerant are treated as a utility, and are supplied from a common source to a plurality of dependent trains in an LNG plant. This allows the dedicated, compression strings, which are normally found in each stand-alone train of a multi-train LNG plant, to be replaced by common compression strings which, in turn, supply the refrigerants to more than one dependent train in the plant. As used hereinafter, the term “dependent train” includes any unit in an LNG plant that lacks its own, dedicated compression string.
[0012] More specifically, the present invention relates to an LNG system that is comprised of two or more dependent trains, each of which converts a feed gas into LNG. Each dependent train includes at least a first refrigerant circuit and a second refrigerant circuit, in series, which cool the feed gas to the cryogenic temperature needed for LNG. The first refrigerant (e.g. propane) flows through a series of primary heat exchangers in the first refrigerant circuit to initially cool the feed gas. A second refrigerant (e.g. mixed refrigerant comprised of nitrogen, methane, ethane, and propane) flows through a cryogenic heat exchange system, comprised of one or more individual heat exchangers, in the second refrigerant circuit to further cool the gas and convert it into LNG. This invention is applicable to other types of cryogenic heat exchange systems, including without limitation those with cascade refrigeration systems that use two or more refrigeration systems, those with a dual mixed refrigerant system, or those with some other refrigeration system, as will be familiar to those skilled in the art. For example, without limiting the scope of this invention, this invention is applicable to cascade refrigeration systems with three refrigeration loops in which the refrigeration from one stage is used to condense the compressed refrigerant in the next stage.
[0013] In dependent trains of the present invention, dedicated compression strings for circulating desired refrigerants through their respective circuits are not required. Instead, a set of common compression strings are provided in the present system to supply refrigerants from a common source to more than one of the dependent trains in the LNG plant.
[0014] If more than one set of common compression strings are required due to the increasing size of an LNG plant (i.e. number of dependent trains to be serviced), a plurality of first compression strings are provided and manifolded together so that compressed first refrigerant from the first compression strings can be directed to various dependent trains as needed. Likewise, a plurality of second compression strings can be manifolded together whereby the second refrigerant from the second compression strings can be directed to various dependent trains as needed.
[0015] It will be recognized that by treating all of the refrigerants in an LNG plant as a utility (i.e. a single first refrigerant supply, a single second refrigerant supply, etc.) and by using independent, common compression strings to supply the refrigerants to the respective refrigerant circuits in a plurality of dependent trains, a significant number of benefits will be realized.
DESCRIPTION OF THE DRAWINGS
[0016] The advantages of the present invention will be better understood by referring to the following detailed description and the attached drawings in which:
[0017] [0017]FIG. 1 (PRIOR ART) is a simplified flow diagram of a typical system for liquefying natural gas; and
[0018] [0018]FIG. 2 is a simplified flow diagram of a system for liquefying natural gas in accordance with the present invention.
[0019] While the invention will be described in connection with its preferred embodiments, it will be understood that the invention is not limited thereto. On the contrary, the invention is intended to cover all alternatives, modifications, and equivalents which may be included within the spirit and scope of the present disclosure, as defined by the appended claims.
DETAILED DESCRIPTION OF THE INVENTION
[0020] Referring more particularly to the drawings, FIG. 1 (Prior Art) schematically illustrates a system and process for liquefying natural gas in a typical LNG plant 10 . As shown, plant 10 is comprised of a plurality of stand-alone trains A and B (only two shown) which are basically identical and independent of each other. As will be understood in the art, a typical LNG plant 10 is built in stages (i.e. trains) so that a second train B is installed when feed gas production capacity exceeds that required for the existing train(s), sufficient new LNG sales contracts have been procured to justify construction of an additional train, and so forth, as will be familiar to those skilled in the art.
[0021] Basically, feed gas enters a respective stand-alone train through an inlet line 11 and flows through one or more primary heat exchangers in a first refrigerant circuit R 1 where the feed gas is initially cooled by heat exchange with a first refrigerant, e.g., propane. The first refrigerant is circulated through the first refrigerant circuit R 1 by a first dedicated compression string C 1 , which includes compressor(s) 37 driven by gas turbines or the like (not shown). The cooled feed gas then passes through a cryogenic heat exchange system, comprised of one or more individual heat exchangers, in second refrigerant circuit R 2 where it is cooled to a cryogenic temperature of LNG, typically about −162° C. (−260° F.) by heat exchange with a second refrigerant, e.g., a mixed refrigerant “MR” (e.g. nitrogen, methane, ethane, and propane). The second refrigerant is circulated through the second refrigerant circuit by a second dedicated compression string C 2 , which includes compressor(s) 23 driven by gas turbines or the like (not shown). Once the pressure of the thus cooled feed gas is reduced to about atmospheric pressure, e.g., by being passed through an expansion valve or hydraulic turbine (not shown), and a flash tank (not shown) to separate LNG from unliquefied gas, produced LNG exits stand-alone trains A and B through outlet 45 . Since the details of operation of a typical stand-alone train A or B in an LNG plant 10 are well known to those skilled in the art, a detailed description is not provided.
[0022] Referring now to FIG. 2, the natural gas liquefying system and process of the present invention is schematically illustrated. Basically, the system illustrated is comprised of a plurality of separate dependent trains (only two shown, AA and BB) located in LNG plant 110 . Trains AA and BB differ from typical LNG trains A and B of FIG. 1 in that each of trains AA and BB do not include compression components, rather each consists essentially of a first refrigerant circuit RR 1 and a second refrigerant circuit RR 2 which, in turn, consist essentially of heat exchange components for reducing the temperature of a feed gas to about −162° C. (−260° F.), which heat exchange components are well known to those skilled in the art. A dependent train may comprise two or more refrigerant circuits.
[0023] In the present invention, feed gas (i.e. natural gas) enters a respective train through inlet line 111 and flows through a series of primary heat exchangers (not shown in FIG. 2) in first refrigerant circuit RR 1 . Any suitable primary heat exchanger arrangement may be utilized in first refrigerant circuit RR 1 , as will be familiar to those skilled in the art. In this embodiment, a first refrigerant is circulated through these primary heat exchangers to initially cool the feed gas in the same manner as described above. For example, without limiting this invention, propane may be used as the first refrigerant. The cooled feed gas continues on through the second refrigerant circuit RR 2 where it passes through a cryogenic heat exchange system, comprised of one or more individual heat exchangers. Any suitable primary heat exchanger arrangement may be utilized in second refrigerant circuit RR 2 , as will be familiar to those skilled in the art. The feed gas is cooled in the cryogenic heat exchange system, comprised of one or more individual heat exchangers, by a second refrigerant to cool the feed gas to a cryogenic temperature of about −162° C. (−260° F.). For example, without limiting this invention, mixed refrigerant “MR” (e.g. nitrogen, methane, ethane, and propane), may be used as the second refrigerant. Once the pressure of the thus cooled feed gas is reduced to about atmospheric pressure, e.g., by being passed through an expansion valve or hydraulic turbine (not shown), produced LNG exits dependent trains AA and BB through outlet(s) 145 .
[0024] In this embodiment, the first compression string CC 1 is located at a common point within plant 110 where it can compress and circulate the first refrigerant, e.g. propane, through the respective first refrigerant circuits RR 1 of a plurality of trains such as AA and BB in FIG. 2. First compression string CC 1 includes compressor(s) 37 driven by suitable drivers 38 , such as gas and/or steam turbines, and/or electric motors, and/or the like, as will be familiar to those skilled in the art. Likewise, the second compression string CC 2 is located at a common point within plant 110 where it can compress and circulate the second refrigerant, e.g. MR, through the respective second refrigerant circuits RR 2 of a plurality of trains such as AA and BB. Second compression string CC 2 includes compressor(s) 23 driven by suitable drivers 38 , such as gas and/or steam turbines, and/or electric motors, and/or the like, as will be familiar to those skilled in the art. In certain embodiments of this invention, one or more of the trains may include one or more dedicated compression strings as needed. It is not required that every train in the system be served by common compression strings; i.e., a plant 110 may also include some independent trains.
[0025] First compression string CC 1 may be comprised of a single compressor or it may be comprised of one or more single or multi-stage compressors, as will be familiar to those skilled in the art. Likewise, second compression string CC 2 may be comprised of a single compressor or it may be comprised of one or more single or multi-stage compressors. A set comprised of a first compressor and a second compressor may be driven by a common shaft or may be driven by individual prime movers, e.g. gas turbines, as the case may dictate and as is familiar to those skilled in the art.
[0026] A single set of first and second compressors may be adequate to circulate the respective refrigerants through the refrigerant circuits of all of the trains. If more that one set of common compressors are needed, it can be seen in FIG. 2 that a plurality of first compression strings CC 1 (four shown) are connected together by a manifold system so that the first refrigerant can be directed from any of these first compression strings CC 1 through the first refrigerant circuit of any or all of the plurality of trains (e.g. either or both trains AA and BB in FIG. 2) by selective manipulation of the appropriate valves (not shown) in the supply and return lines 50 , 51 .
[0027] The same is true of a plurality of second compression strings CC 2 which are connected together by a second manifold system which allows any of the second compression strings to circulate a second refrigerant through one or more of the second refrigerant circuits in any of the trains in plant 110 . As seen in FIG. 2, the output from the respective compressors strings flow through the supply lines (e.g., solid lines 50 ) and the return flows back to the respective compression strings through the return lines (e.g., dotted lines 51 ).
[0028] By treating the refrigerants in the plant 110 as a utility (i.e. a single first refrigerant supply and a single second refrigerant supply ) and by using independent, common compression strings to supply these respective refrigerants to the refrigerant circuits in a plurality of trains, a significant number of benefits is realized, some of which are as follows: (1) Significantly less equipment is needed, thereby reducing the capital costs of the LNG plant; (2) A single spare compression string can be installed to back up any of the other common compression strings being used to supply refrigerant to the different trains in the LNG plant; (3) If one compression string fails while circulating a refrigerant to a particular train, the affected train can be immediately switched to a back-up compression string without substantially halting LNG production through that train; and (4) By switching to a back-up second compression string, the cryogenic heat exchange system, comprised of one or more individual heat exchangers, can be kept cold during repair of the compressor(s) which had been supplying MR to the heat exchange system in the affected train.
[0029] While the present invention has been described in terms of one or more preferred embodiments, it is to be understood that other modifications may be made without departing from the scope of the invention, which is set forth in the claims below. For example, refrigerants other than the ones specified herein may be utilized, etc.
GLOSSARY OF TERMS
[0030] cryogenic temperature: any temperature of about −40° C. (−40° F.) and lower;
[0031] dependent train: any unit in an LNG plant that lacks its own, dedicated compression string;
[0032] flash tank: a gas/liquid separator;
[0033] LNG: liquefied natural gas at substantially atmospheric pressure and at temperatures of about −162° C. (−260° F.);
[0034] stand-alone train: a unit in an LNG plant comprised of all of the individual components necessary to liquefy a stream of feed gas into LNG and send it on to storage. | Natural gas liquefaction systems are provided wherein the dedicated compression strings normally found in each liquefaction train of a multi-train LNG plant are replaced by common compression strings which, in turn, supply the respective refrigerants (e.g. propane and mixed refrigerant) to more than one of the multi-trains. This allows the refrigerants to be treated as a utility in that all of the refrigerants are supplied from a respective single source by the common compression strings. | 5 |
CROSS-REFERENCE TO RELATED PATENT APPLICATION
This application claims the benefit of Korean Patent Application No. 10-2005-0069115, filed on Jul. 28, 2005, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a data recording medium and method of manufacturing the same, and more particularly, to a ferroelectric recording medium and method of manufacturing the same.
2. Description of the Related Art
As internet technology develops, demand for recording media which can record a huge amount of information such as moving pictures, in particular, portable recording media, has increased. This demand is an important factor leading the next-generation information recording media market.
Recording media which can record a huge amount of information and devices for recording and reading information in the recording medium are the most essential issues for the information recording media market.
Portable, non-volatile data recording devices are classified into solid-state memory devices, for example, flash memory, and disk type memory devices, for example, hard disks.
Since the capacity of solid-state memory devices will only increase up to several gigabites (GB) in the next several years, solid-state memory devices may not be used as large data recording devices whose capacity must be greater than several gigabites in the near future. However, solid-state memory devices may be used for high speed apparatuses such as personal computers (PC). For the time being, hard disk type memory devices may be used as a main recording apparatus.
A typical magnetic hard disk mounted in a portable apparatus will have a capacity of 10 GB in the near future, but a capacity of more than 10 GB may not be accomplished due to a superparamagnetic effect.
A memory device using a scanning probe technique for recording data and using a ferroelectric material as a recording material has been developed. When using the scanning probe technique, i.e., a scanning probe microscope (SPM) technique, an area of several to tens of nanometers can be probed by a probe. In addition, since a ferroelectric material is used as a recording medium, a superparamagnetic effect will not occur, unlike in a magnetic recording medium. The recording density in the recording device using ferroelectric material can be greater than in the magnetic recording medium.
In the recording medium using an SPM technique, recorded data are defined by the polarity of the polarization of the ferroelectric material.
Due to ferroelectric polarization, an electric field is emanating from the surface. When an appropriate probe is placed into that field, the field induces a charge depletion or accumulation region at the apex of the tip. This in turn induces a capacitance or resistance change of the probe. Depending on the polarity of the ferroelectric polarization, the resistance or capacitance is increased or decreased. Data recorded on a ferroelectric recording medium using the SPM technique can be read by measuring the change in the capacitance or resistance of the probe. Writing is done by locally changing the ferroelectric polarization of the medium. This is done by applying an electric voltage to the probe, where the voltage is high enough to induce ferroelectric switching in the medium.
As described above, a ferroelectric recording medium using an SPM can have higher data recording density than a magnetic recording medium. However, it should be considered that the region of one bit data recording is a polarized area. In order to further increase a data recording density of a ferroelectric recording medium, the size of the bit data recording region in a ferroeletric recording medium should be reduced.
However, since the reduction in the size of the bit data recording region is very much dependent on the reduction of the probe size, a further increase of the data recording density of the ferroelectric recording medium will be difficult unless epoch-making technology for reducing the probe size is developed.
SUMMARY OF THE INVENTION
The present invention provides a ferroelectric recording medium with an increased data recording density.
The present invention also provides a method of manufacturing the ferroelectric recording medium having an increased data recording density.
According to an aspect of the present invention, there is provided a ferroelectric recording medium including: a substrate; a patterned supporting layer which is formed on the substrate, the patterns having at least two lateral surfaces; and data recording layers formed on the lateral surfaces of the patterns.
The data recording layers may include several data recording layers disposed on the lateral surfaces of the patterns of the supporting layer. The patterns of the supporting layer may have a polygonal shape having at least three lateral surfaces or may be a bar type.
A plurality of patterns may be formed on the substrate and disposed at uniform intervals.
The supporting layer may be formed of one or more selected from the group consisting of but not limited to titanium dioxide (TiO 2 ), vanadium dioxide (VO 2 ), niobium dioxide (NbO 2 ), zirconium dioxide (ZrO 2 ), oxides of iron, titanium nitride (TiN), vanadium nitride (VN), niobium nitride (NbN), zirconium nitride (ZrN), iron nitride (Fe 2 N), strontium oxide (SrO), strontium nitride (Sr 2 N 3 ), tantalum oxide (Ta 2 O 5 ) and tantalum nitride (Ta 2 N). The supporting layer may also be formed of one or more selected from the group consisting of titanium (Ti), vanadium (V), niobium (Nb), zirconium (Zr), iron (Fe), strontium (Sr) and tantalum (Ta).
The data recording layers may be formed of one selected from the group consisting of but not limited to lead zirconate titanate (PZT), strontium bismuth tantalate (SBT), strontium bismuth titanate (SBT) lithium titanate (LTO), lithium tantalate (LTO), strontium bismuth niobate (SBN), lead titanate (PTO), bismuth ferrite (BFO), bismuth titanate (BTO), and potassium niobate (KNO).
According to another aspect of the present invention, there is provided a method of manufacturing a ferroelectric recording medium, the method including: forming a supporting layer on a substrate; patterning the supporting layer into patterns having at least two lateral surfaces; forming source material layers on the lateral surfaces of the patterns; and diffusing a source material into the patterns of the supporting layer and reacting the source material with the material of the supporting layer. To trigger the reaction between the source material and the material of the supporting layer, and for diffusion, a temperature of 400° C. or more may be used.
The source material layers may be formed of a material that reacts with the material of the supporting layer to form a layer formed of one selected from the group consisting of but not limited to PZT, strontium bismuth tantalate (SBT), strontium bismuth titanate (SBT), lithium titanate (LTO), lithium tantalate (LTO), strontium bismuth niobate (SBN), PTO, BFO, BTO, and KNO on the lateral surfaces of the patterns. The basis for the source material may be, but is not limited to lead (Pb), potassium (K), bismuth (Bi), or lithium (Li).
According to another aspect of the present invention, there is provided a method of manufacturing a ferroelectric recording medium, the method including: forming a supporting layer on a substrate; forming a mask on the supporting layer to define a portion of the supporting layer; etching the supporting layer around the mask which produces patterns; placing the etched product in a gas atmosphere including a source material gas that reacts with the lateral surfaces of the patterns and diffuses into the pattern to form a ferroelectric lateral layer. To trigger the reaction between the source material and the material of the supporting layer, and for diffusion, a temperature of 400° C. or more may be used.
In the forming of the mask, the supporting layer may be defined into patterns of polygonal shapes having at least three lateral surfaces or may be a bar type.
The supporting layer may be formed of one or more selected from the group consisting of but not limited to TiO 2 , VO 2 , NbO 2 , ZrO 2 , oxides of iron, TiN, VN, NbN, ZrN, Fe 2 N, SrO, Sr 2 N 3 , Ta 2 O 5 and Ta 2 N. The supporting layer may also be formed of one or more selected from the group consisting of but not limited to Ti, V, Nb, Zr, Fe, Sr and Ta.
The source material gas may be a material gas that reacts with the supporting layer to form a layer formed of one selected from the group consisting of but not limited to PZT, strontium bismuth tantalate (SBT), strontium bismuth titanate (SBT), lithium titanate (LTO), lithium tantalate (LTO), SBN, PTO, BFO, BTO, and KNO on the lateral surfaces of the supporting layer. The basis for the source material gas may be, but is not limited to Pb, K, Bi, or Li.
To trigger the reaction between source material and the material of the supporting layer, and for diffusion the fabrication may be performed at 400° C. or more. At the end, a final heat treatment using for example a rapid thermal annealing (RTA) process may be applied.
The ferroelectric recording medium has a high data recording density and offers high speed data recording and reading capabilities.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and other features of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which:
FIG. 1 is a perspective view of a ferroelectric recording medium according to a first exemplary embodiment of the present invention;
FIG. 2 is a perspective view of a ferroelectric recording medium according to a second exemplary embodiment of the present invention;
FIG. 3 is a cross-sectional view of the ferroelectric recording medium taken along the line 3 - 3 ′ of FIG. 1 or 2 ;
FIGS. 4 through 8 are cross-sectional views illustrating steps in a method of manufacturing a ferroelectric recording medium according to a first exemplary embodiment of the present invention;
FIGS. 9 and 10 are cross-sectional views illustrating steps in a method of manufacturing a ferroelectric recording medium according to a second exemplary embodiment of the present invention;
FIG. 11 is a cross-sectional view illustrating access by a probe in a conventional recording medium; and
FIG. 12 is a cross-sectional view illustrating access by a probe in a recording medium according to an exemplary embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the present invention are shown. In the drawings, the sizes and thicknesses of layers and regions are exaggerated for clarity.
A ferroelectric recording medium according to a first exemplary embodiment of the present invention (hereinafter, referred to as a first recording medium) is explained.
Referring to FIG. 1 , the first recording medium includes bar type data recording units S 1 in which data is recorded and which is formed on a substrate 40 . The substrate 40 is used as a lower electrode. The substrate 40 is formed of a predetermined metal, for example, platinum (Pt) or iridium (Ir). Each of the data recording units S 1 may include a supporting layer 42 , and first and second recording layers 44 and 46 . The supporting layer 42 supports the first and second recording layers 44 and 46 . Both lateral surfaces of the supporting layer 42 are vertical. The first recording layer 44 covers one side of the supporting layer 42 and the second recording layer 46 covers another side of the supporting layer 42 .
In FIG. 1 , the first and second recording layers 44 and 46 appear that they are formed on both the lateral surfaces of the supporting layer 42 or that they are adhered to the both lateral surfaces of the supporting layer 42 . However, considering a method of manufacturing the data recording unit S 1 described below, the first and second recording layers 44 and 46 are formed by diffusing a source material into both the lateral surfaces of the supporting layer 42 . Therefore, the first and second recording layers 44 and 46 are disposed in a predetermined depth inward from the lateral surfaces of the supporting layer 42 . The supporting layer 42 is formed of TiO 2 or one or more selected from the group consisting of but not limited to TiO 2 , VO 2 , NbO 2 , ZrO 2 , oxides of iron, TiN, VN, NbN, ZrN, Fe 2 N, SrO, Sr 2 N 3 , Ta 2 O 5 and Ta 2 N.
Alternatively, the supporting layer 42 may be formed of a pure metal. The pure metal may be one or more metals selected from the group consisting of Ti, V, Nb, Zr, Fe, Sr and Ta. The first and second recording layers 44 and 46 may be ferroelectric layers. For example, each of the first and second recording layers 44 and 46 may be formed of one selected from the group consisting of but not limited to PZT, strontium bismuth tantalate (SBT), strontium bismuth titanate (SBT), lithium titanate (LTO), lithium tantalate (LTO), SBN, PTO, BFO, BTO, and KNO. Like this, the first and second recording layers 44 and 46 are ferroelectric layers.
The polarization of the first and second recording layers 44 and 46 is initially aligned in a certain direction. The polarization of the first and second recording layers 44 and 46 is maintained in the initially aligned direction until an external predetermined voltage, which can change the polarization, is applied thereto. The polarization in certain areas of the first and second recording layers 44 and 46 , which may be upward or downward, indicates that a bit of data is recorded in the certain area of the first and second recording layers 44 and 46 .
Accordingly, data recorded on the first and second recording layers 44 and 46 is maintained until a voltage is applied to the first and second recording layers 44 and 46 to change data. A plurality of data recording units S 1 are disposed on the substrate 40 . The data recording units S 1 are disposed parallel to each other and are separated from each other by predetermined intervals.
Next, a ferroelectric recording medium according to a second exemplary embodiment of the present invention (hereinafter, referred to as a second recording medium) is explained. Referring to FIG. 2 , the second recording medium includes data recording units S 2 , in which data is stored, on a substrate 40 . The data recording unit S 2 is similar to the data recording unit S 1 of the first recording medium of FIG. 1 , but the structures are different.
Each of the data recording units S 2 may include a supporting layer 48 and a recording layer 50 . The supporting layer 48 may be composed of the same material as the supporting layer 42 of the first recording medium of FIG. 1 and the recording layer 50 may be composed of the same material as the first or second recording layer 44 or 46 of the first recording medium of FIG. 1 . However, the supporting layer 48 has a polygonal structure, for example, a square pillar or a pillar comprising three lateral surfaces, and the recording layer 50 covers four lateral surfaces of the supporting layer 48 . The relationship between the supporting layer 48 and the recording layer 50 may be the same as the relationship between the supporting layer 42 and the first and second recording layers 44 and 46 of the first recording medium of FIG. 1 .
Since the recording layer 50 covers the four lateral surfaces of the supporting layer 48 of the second recording medium of FIG. 2 , the recording layer 50 can be divided into four portions corresponding to the four lateral surfaces of the supporting layer 48 . Bit data is independently recorded on each lateral surface of the recording layers 50 . Accordingly, the first recording medium of FIG. 1 can record 2-bit data in the data recording unit S 1 , but the second recording medium of FIG. 2 can record 4 -bit data in the data recording unit S 2 . A plurality of the data recording units S 2 are disposed on the substrate 40 of the second recording medium of FIG. 2 , and the data recording units S 2 are separated from each other by equal intervals in the four directions.
According to the first and second recording media illustrated in FIGS. 1 and 2 , a ferroelectric recording medium of an exemplary embodiment of the present invention may be modified in various ways. For example, the supporting layer in the ferroelectric recording medium according to an exemplary embodiment of the present invention may be a pentagonal, a hexagonal or even a circular pillar instead of the square pillar illustrated in FIG. 2 .
FIG. 3 is a cross-sectional view of the first recording medium taken along the line 3 - 3 ′ of FIG. 1 or the second recording medium taken along the line 3 - 3 ′ of FIG. 2 . The resultant structure shown in FIG. 3 may be formed by the methods described below.
First, a method of manufacturing a ferroelectric recording medium according to a first exemplary embodiment of the present invention (hereinafter, referred to as a first manufacturing method) is explained with reference to FIGS. 4 through 8 .
Referring to FIG. 4 , a supporting layer 42 is formed on a substrate 40 . The substrate 40 is used as a lower electrode. The substrate 40 may be formed of a predetermined metal, for example, platinum (Pt) or iridium (Ir). The supporting layer 42 is used to support recording layers. The supporting layer 42 may be formed by depositing TiO 2 on the substrate 40 . Alternatively, the supporting layer 42 may be formed of one or more selected from the group consisting but not limited to TiO 2 , VO 2 , NbO 2 , ZrO 2 , oxides of iron, TiN, VN, NbN, ZrN, Fe 2 N, SrO, Sr 2 N 3 , Ta 2 O 5 and Ta 2 N. The supporting layer 42 may also be formed of one or more selected from the group consisting of Ti, V, Nb, Zr, Fe, Sr and Ta.
The supporting layer 42 may be formed on the substrate 40 . After forming the supporting layer 42 , a mask P 1 defining a predetermined region of the supporting layer 42 is formed on the supporting layer 42 . The mask P 1 may be a photosensitive layer pattern.
Referring to FIG. 5 , the supporting layer 42 is etched until the upper surface of the substrate 40 is exposed. Through the etching process, the portion of the supporting layer 42 not disposed under the mask P 1 is removed.
Next, referring to FIG. 6 , a source material layer 60 is formed to cover exposed surfaces of the supporting layer 42 on the substrate 40 . The source material layer 60 can react with the supporting layer 42 during an annealing process to form a ferroelectric layer. For example, when the supporting layer 42 is a TiO 2 layer, the source material layer 60 may be a lead oxide layer. The source material layer 60 may cover the whole surface of the mask P 1 .
After forming the source material layer 60 , the mask P 1 is removed. The portion of the source material layer 60 formed on the surface of the mask P 1 is removed together with the mask P 1 in this process. Thus, as shown in FIG. 7 , the source material layer 60 is left on the top surface of the substrate 40 and the lateral surfaces of the supporting layer 42 , and the top surface of the supporting layer 42 is exposed. After the mask P 1 is removed, heat treatment for the resultant structure from which the mask P 1 is removed is performed at predetermined temperature ranges. For example, when a rapid thermal annealing (RTA) process is performed, the temperature range may be 400 to 1400° C. or, in an exemplary embodiment, 500° C. or more.
During the annealing process, the source material layer 60 formed on the substrate 40 is removed through evaporation, and the source material layer 60 formed on the lateral surfaces of the supporting layer 42 diffuses into and reacts with the supporting layer 42 . Therefore, first and second recording layers 44 and 46 are formed on the lateral surfaces of the supporting layer 42 , as illustrated in FIG. 8 . For example, each of the first and second recording layers 44 and 46 may be formed of one selected from the group consisting of but not limited to PZT, strontium bismuth tantalate (SBT), strontium bismuth titanate (SBT), lithium titanate (LTO), lithium tantalate (LTO), SBN, PTO, BFO, BTO, and KNO.
Bit data is recorded in the first and second recording layers 44 and 46 . The diffusion rate of the source material layer 60 is controlled by controlling heat treatment conditions such as heat treatment time or heat treatment temperature. Therefore, the widths of the first and second recording layers 44 and 46 are also controlled by controlling the heat treatment conditions. Consequently, the width of a bit data recording region can be controlled by control of the heat treatment conditions and by the thickness of the source material layer.
Next, a method of manufacturing a ferroelectric recording medium according to a second exemplary embodiment of the present invention (hereinafter, referred to as a second manufacturing method) is explained with reference to FIGS. 9 and 10 .
Referring to FIG. 9 , the mask P 1 is formed according to the first manufacturing method. After forming the mask P 1 , the product is placed in a gas atmosphere including a source material gas 70 . The source material gas 70 may be a material gas which can react with the supporting layer 42 to form a ferroelectric layer. For example, when the supporting layer 42 is formed of TiO 2 , the source material gas 70 may be PbO gas. While the supporting layer 42 is placed in the source material gas 70 , the lateral surfaces of the supporting layer 42 contact the source material gas 70 . While the temperature is above a certain value, for example 400 C, reaction of the source material with the supporting material occurs and diffusion into the supporting material takes place.
Referring to the mentioned example, if the source material gas is PbO and the supporting material is TiO 2 , lead titanium oxide (PbTiO 3 ) may be formed in that way. The heating may be obtained in the same way as the above-described heat treatment in the first manufacturing method. During the heat treatment, the source material gas 70 contacting the lateral surfaces of the supporting layer 42 , diffuses into and reacts with the supporting layer 42 as shown on the right of FIG. 9 . Consequently, a ferroelectric layer 95 is formed inward from the lateral surfaces of the supporting layer 42 . In this exemplary embodiment, the mask P 1 should be resistant to the temperature used in this manufacturing process.
Referring to FIG. 10 , the first and second recording layers 44 and 46 formed of the ferroelectric material are thus formed on the lateral surfaces of the supporting layers 42 through the heat treatment. The mask P 1 is removed after the heat treatment.
The difference in operating speeds of a conventional recording medium and a recording medium according to an exemplary embodiment of the present invention will now be described. FIG. 11 is a cross-sectional view illustrating access by a probe in a conventional recording medium. FIG. 12 is a cross-sectional view illustrating access by a probe in a recording medium according to an exemplary embodiment of the present invention.
In the case of a conventional recording medium as illustrated in FIG. 11 , a case when a probe 90 accesses first and second recording layers 80 and 82 will be considered. The probe 90 searches for and accesses the first recording layer 80 , and then a predetermined operation is performed. Subsequently, the probe 90 searches for the second recording layer 82 in order to access the second recording layer 82 . That is, the probe 90 should search for each recording layer one by one in order to access it. However, in the case of a recording medium according to an exemplary embodiment of the present invention, at least the two recording layers 44 and 46 are disposed on opposite surfaces of the supporting layer 42 .
Accordingly, when the probe 90 accesses the recording layer 44 of the two recording layers 44 and 46 , the probe 90 can access the recording layer 46 by only moving across the upper surface of the supporting layer 42 . That is, it is unnecessary to search for the subsequent recording layer when the probe 90 has already accessed one of two adjacent recording layers which are opposite to each other and where the supporting layer 42 exists between the two recording layers 44 and 46 . Therefore, the ferroelectric recording medium according to an exemplary embodiment of the present invention can read and record data faster than the conventional recording medium.
When a portion of the source material layer 60 remains on the lateral surfaces of the supporting layer 42 after the heat treatment process in the first method, the residual portion of the source material layer 60 may be removed. The heat treatment may be performed using various heat treatment apparatuses. In addition, the data recording layer may be formed of other ferroelectric materials which are not described above.
As described above, the ferroelectric recording unit according to the exemplary embodiments of the present invention includes a supporting layer and at least two data recording layers formed on the lateral surfaces of the supporting layer. Bit data is independently recorded in the data recording layers. The data recording density of ferroelectric recording medium according to the present invention is increased by a factor corresponding to the number of lateral recording layers.
In addition, since two data recording layers are formed on opposite sides of a supporting layer in the ferroelectric recording medium according to the exemplary embodiments of the present invention, when a probe accesses a selected one of the two data recording layers, searching for the other data recording layer is not necessary because the location of the other data recording layer is exactly defined from the selected one. That is, in the recording medium of the present invention, the probe can access two data recording layers by searching for only one of the data recording layers. Therefore, the ferroelectric recording medium according to the exemplary embodiments of the present invention has a high operating speed for recording and reading data.
While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims. | Provided are a ferroelectric recording medium and a method of manufacturing the same. The ferroelectric recording medium includes a substrate, a plurality of supporting layers which are formed on the substrate, each of the supporting layers having at least two lateral surfaces; and data recording layers formed on the lateral surfaces of the supporting layers. First and second data recording layers may be respectively disposed on two facing lateral surfaces of each of the supporting layers. The supporting layers may be polygonal pillars having at least three lateral surfaces. A plurality of the supporting layers can be disposed at uniform intervals in a two-dimensional array. | 8 |
TECHNICAL FIELD
[0001] The invention relates to the field of Connectivity Fault Management in a communications network, in particular a network that supports Equal Cost Multiple Paths.
BACKGROUND
[0002] Operations, Administration and Maintenance (OAM) is a term used to describe processes, activities, tools, standards and so on that are involved with operating, administering, managing and maintaining a communication network. OAM requires fault management and performance monitoring, connectivity fault management and link layer discovery.
[0003] CFM is a protocol of OAM that provides Connectivity Fault Management (CFM). The CFM protocol uses Maintenance Domains (MD) for monitoring levels of service providers, core networks or system operators. Each level has Maintenance Associations (MA) dedicated to monitoring specific provider/provider or provider/customer service. Each MA depends on a set of Maintenance Points (MPs) for monitoring. An MA is established to verify the integrity of a single service instance. A Maintenance Association Edge Point (MEP) is an actively managed CFM entity which provides the extent of an MA and is associated with a specific port of a service instance. It can generate and receive CFM Protocol Data Units (PDUs) and track any responses. It is an end point of a single MA, and is an endpoint for each of the other MEPs in the same MA.
[0004] CFM PDUs are transmitted by a MEP in order to monitor the service to which the transmitting MEP belongs. A problem arises in Equal-Cost Multiple Paths routing (ECMP) networks where CFMs cannot be guaranteed to take the same path as the data.
[0005] ECMP routing is a forwarding mechanism for routing packets along multiple paths of equal cost. An aim of ECMP is to equalise distributed link load sharing. Referring to FIG. 1 , there is illustrated schematically a very simple network architecture in which data sent between two endpoints 1 , 2 can be sent via intermediate nodes 3 or 4 at equal cost.
[0006] Some data packets are sent via intermediate node 3 and others are sent via intermediate node 4 . In this way the load on the network is balanced.
[0007] Shortest Path Bridging (SPB) enables the use of link state protocols (IS-IS) for constructing active topologies within a Bridged Network. For more information, see IEEE Std 802.1aq-2012, Shortest Path Bridging. Recent standardization work within IEEE802.1 enhances SPB by enabling ECMP support on SPBM services that use the same VID identifier, as described in P802.1Qbp/D1.0 Equal Cost Multiple Path (ECMP). P802.1Qbp discusses the services supporting ECMP connectivity and, in particular, defines two types of ECMP connectivity. One is associated with point-to-point (PtP) ECMP services provided by ECMP devices that support flow filtering. The other is a generic Virtual LAN (VLAN) service associated with a specific VLAN Identifier (VID) that is mapped to ECMP operation (SPBM VLAN MA in clause 27.18.1 in P802.1Qbp/D1.0 Equal Cost Multiple Path).
[0008] ECMP connectivity paths may use the same Bridging VLAN Identifier (B-VID) in their tags but the service connectivity provided by these paths are different than that associated with frames having the same B-VID and controlled by traditional L2 control protocols like spanning tree or SPB. A typical example of connectivity instances that use the same VID but are not members of a VLAN are Traffic Engineered Service Instances (TESIs) in Provider Backbone Bridges-Traffic Engineering (PBB-TE). ECMP connectivity is similar to that of TESIs but it has a further property that a superset of all ECMP paths identified by the same VID (and endpoints) is not a tree topology. A VLAN on the other hand is always defined in a context of a tree (see clause 7 in IEEE Std 802.1Q-2011, VLAN aware Bridges).
[0009] Shortest Path Bridging-MAC address mode (SPBM) connectivity is different to ECMP connectivity. SPBM connectivity is similar to that of PBB-TE (in that it there is no flooding, no learning, it is symmetric, and uses only explicit entries in a Filtering Database (FDB) for forwarding), which means in practice that CFM enhancements for PBB-TE (described in IEEE Std 802.1Qay-2009 PBB-TE and IEEE Std 802.1Q-2011, VLAN aware Bridges) can be used almost identically for SPBM MAs. Nevertheless, ECMP connectivity differs in that multiple paths are enabled for the same end points. The same VID and correspondingly the ECMP CFM require further changes in order to monitor the associated services. As a result ECMP MAs need to be separated from SPBM MAs, and the associated monitoring protocol tools need to be modified as their operation depends on the type of connectivity that they monitor.
[0010] ECMP Point-to-Point (PtP) path connectivity and the associated monitoring tools are described in P802.1Qbp, but P802.1Qbp does not describe ECMP multipoint monitoring in a consistent manner. In particular, the “SPBM VLAN” connectivity is associated with an overall connectivity identified by the same SPBM VID value. However, an overall SPBM-VID connectivity is meaningless for ECMP, because ECMP creates multiple independent connectivity paths between subsets of nodes that are members of the SPBM-VID. The operational status of each of the ECMP subsets is therefore independent of the operational status of the other ECMP subsets identified by the same SPBM-VID. This ECMP independency means that, when using SPBM OAM mechanisms and an overall SPBM-VID connectivity is reported as being error-free, the connectivity on ECMP subsets could be non-operational. The above connectivity characteristic of the SPBM VLAN Maintenance Association (MA) creates problems for monitoring multipoint ECMP services. In particular, since the SPBM VLAN Continuity Check protocol attempts to monitor the overall “VLAN” service, the scope of propagation of the Continuity Check Message (CCM) PDUs is provided by the use of a broadcast address (constructed using SPBM default Backbone Service Identifier, I-SID). The result of this is that monitored connectivity is different from the connectivity associated with the monitored data traffic. In addition, the operation of Link Trace Messages (LTM) becomes quite difficult and the extent of reachability of the LTMs can be quite different to that defined by the configured ECMP related MAC address entries.
[0011] Furthermore, the placement of the “SPBM VLAN MEP” in parallel to ECMP PtP path Maintenance Association Edge Points (MEPs) breaks the operation of the ECMP path MAs (stopping every ECMP Path CFM PDU on the SPBM-VID as can be seen from FIG. 27-4 in P802.1Qbp/D1.0.)
SUMMARY
[0012] It is an object to provide a mechanism by which Connectivity Fault Management Maintenance Associations can be monitored in an Equal Cost Multiple Paths network.
[0013] According to a first aspect, there is provided a method of monitoring a Maintenance Association (MA) for Connectivity Fault Management (CFM) in a network supporting Equal Cost Multiple Paths (ECMP). A set of ECMP paths is generated for sending data between endpoints in the network. Furthermore, a set of ECMP MAs is created that are used for monitoring the generated ECMP paths between the endpoints. The created set of ECMP MAs is subsequently used for sending monitoring packets. An advantage of this is that ECMP paths MAs conform to existing CFM operation and are compatible with both ECMP point to point path MAs and ECMP multipoint path MAs.
[0014] As an option, each monitoring packet comprises a CFM Protocol Data Unit. An advantage is that the forwarding parameters of the PDU are the same as those for monitored data packets sent using the ECMP paths, and so the monitoring packets will traverse the same path.
[0015] As an option, the method includes generating the set of ECMP paths using ECMP Point to Point paths, wherein the Point to Point paths comprising a set of equal shortest length connectivity paths between the two end points.
[0016] As an alternative option, the method includes generating the set of ECMP paths using ECMP multipoint paths. The multipoint paths include a set of connectivity multipoint paths among the same end points. As a further option, each ECMP path comprises an ECMP multipoint path having N endpoints. Each ECMP multipoint path may be identified using a Group address. As a further option, each ECMP multipoint path associated with the two end points may be identified using a Group MAC address. In this case, the Group MAC address is optionally constructed by applying an operation on Backbone Service Identifier values associated with the ECMP multipoint paths.
[0017] As an option, the method further includes monitoring an ECMP path by sending the monitored packet using the identifier associated with the specific path. Optional examples of such an identifier are a Flow Hash and a Group MAC address identifying the path.
[0018] As an alternative option, the method further includes monitoring a plurality of ECMP paths by sending monitored packets in groups cyclically on each monitored ECMP path, using the identifier associated with each monitored ECMP path.
[0019] According to a second aspect, there is provided a node for use in a communications network supporting ECMP. The node is provided with a processor for generating a set of ECMP path MAs for sending data between end points. The processor is further arranged to create a set of ECMP MAs for monitoring the generated ECMP paths between the endpoints. A transmitter is also provided for sending monitoring packets using the set of generated ECMP paths. An advantage of this is that ECMP paths MAs conform to existing CFM operations, and are compatible with both ECMP point to point path MAs and ECMP multipoint path MAs. The node is optionally implemented in any type of device that implements ECMP.
[0020] As an option, the node is provided with a computer readable medium in the form of a memory for storing information mapping at least one Service Identifier to each generated ECMP path.
[0021] The processor is optionally arranged to generate monitoring packets using ECMP Point to Point paths comprising a set of equal shortest length connectivity paths between the end points.
[0022] As an alternative option, the processor is arranged to generate monitoring packets using ECMP multipoint paths comprising a set of connectivity multipoint paths among a plurality of end points. As a further option, the processor is arranged to identify an ECMP multipoint path monitoring packet using a Group MAC address for each ECMP path. In this case, the processor is optionally arranged to construct each Group MAC address by applying an operation on Backbone Service Identifier values associated with the ECMP multipoint paths.
[0023] According to a third aspect, there is provided a computer program comprising computer readable code which, when run on a node, causes the node to perform the method as described above in the first aspect.
[0024] According to a fourth aspect, there is provided a computer program product comprising a non-transitory computer readable medium and a computer program described above in the third aspect, wherein the computer program is stored on the computer readable medium.
[0025] According to a fifth aspect, there is provided a vessel or vehicle comprising the node described above in the second aspect.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] FIG. 1 illustrates schematically in a block diagram a network architecture showing the principles of Equal Cost Multiple Path routing:
[0027] FIG. 2 is a flow diagram showing steps according to an embodiment;
[0028] FIG. 3 illustrates schematically in a block diagram an exemplary node; and
[0029] FIG. 4 illustrates schematically in a block diagram an exemplary vessel or vehicle.
DETAILED DESCRIPTION
[0030] A consistent way of enabling OAM monitoring for Connectivity Fault Management for both ECMP PtP path MAs and ECMP Multipoint path MAs is provided. “Fate sharing” is guaranteed by using the same forwarding parameters for monitoring packets such as CFM PDUs monitoring the ECMP service as for monitored data frames. In particular, the destination address of CFM PDUs associated with ECMP path MAs is the same address used to reach remote MEPs within the same MA, and is provided by the configuration of the MA itself. Each specific ECMP is identified by a Flow Hash value and any subsets of ECMP paths within the same PtP path are identified by the associated subset of Flow Hash values.
[0031] An ECMP path MA is associated with a connectivity path connecting a specific group of endpoints or with a subset (not necessarily proper) of equal cost paths connecting the same end points. In the latter case, the corresponding CFM PDUs are sent in groups cyclically on every monitored path, using an identifier associated with every monitored path. The number of CFM PDUs in every group depends on the specific CFM PDU: For example, for CCMs, at least four CCMs must be sent on a single monitored path before moving to the next one. For Loopback Messages (LBMs), as many LBMs as provided by the administrator that initiates the LBM are sent. Only one LTM need be sent. This is because CCMs are sent periodically, and a fault is only reported when more than three consecutive CCMs are in error (so we need to send at least four on the same path to be able to check it). The periodicity of LBMs (if any) is configurable and correspondingly the number of LBMs on individual paths must be based on the configuration setting. LTMs are set to identify individual nodes along the path, and so only one LTM on each individual path is required.
[0032] In the case of ECMP multipoint path services, the destination_address parameter of the associated monitoring CFM PDUs is set cyclically to the SPBM Group MAC address associated with the monitored multipoint service. SPBM Group MAC address assignment can be automated.
[0033] In more detail, two ECMP connectivity paths are defined as follows:
[0000] 1. ECMP PtP path: This is the complete set of equal shortest length connectivity paths between two specific end points as constructed by ECMP. In addition to what is described in P802.1Qbp/1.0, LB and LT use the same cyclic methods when a subset of Flow Hash values is provided.
2. ECMP multipoint path: This is the complete set of connectivity multipoint paths among more than two end points as constructed by ECMP. A single multipoint path within an ECMP multipoint path of N endpoints is identified either by:
(a). N Group MAC addresses constructed as follows: the first 3 bytes corresponding to the SPsourceID of the initiating Backbone Edge Bridge (BEB) and the last 3 bytes corresponding to the same I-SID identifying the N endpoint connectivity (this I-SID value may be automated to, for example, be the least backbone I-SID value on the set of I-SID values mapped to an ECMP-VID operation within the Backbone Service Instance table on the terminating BEBs having the least SPsourceID), that is: (SPsourceID[1]-ISID, SPsourceID[2]-ISID, . . . , SPsourceID[N]-ISID); or
(b). A single Group MAC address for all endpoints constructed as follows: the first 3 bytes corresponding to the IEEE 802.1Q Backbone Service Instance Group address OUI (see clause 26.4 in IEEE Std 802.1Q-2011, VLAN aware Bridges) and the last three bytes corresponding to the same I-SID identifying the N endpoint connectivity (this I-SID value chosen could be automated to, for example, be the least backbone I-SID value on the set of I-SID values mapped to an ECMP-VID operation within the Backbone Service Instance table on the terminating BEBs having the least SPsourceID). That is the same group address that is used for all I-SID endpoints corresponding to the Backbone Service instance Group Address.
[0034] The choice between (a) and (b) type of addressing described above is made by configuration. Note that the selection of (a) or (b) depends on how the ECMP multipoint connectivity is set up. Option (a) requires the set up N individual MAC addresses for an N point connectivity, while option (b) requires a single MAC address for an N-point connectivity. Option (a) provides better coverage at the expense of increased complexity.
[0035] Other multipoint paths (up to 16 for each group, a or b) within the same ECMP multipoint connectivity associated with exactly the same N endpoints can be identified by using Group MAC addresses constructed by the above sets by x:oring the I-SID values in (a) or (b) type addressing using tie break masks described in 28.8 in IEEE Std 802.1aq-2012, Shortest Path Bridging.
[0036] In order to enable ECMP operation, an I-SID to path mapping table must be configured for all local I-SIDs that map to the B-VID indicating ECMP operation on the BEBs Backbone Service Instance table. Note that there may be a default configuration set to distribute I-SIDs equally to all ECMP paths. In this case, I-SIDs can be mapped in increasing order to paths. Table 1 below is an example of such a table:
[0000]
TABLE 1
Exemplary mapping of I-SIDs to paths.
I-SID 1 , I-SID 2 , . . . , I-SID k
Path 1
I-SID k+1 , . . . , I-SID k+m
Path 2
I-SID p , . . . , I-SID z
Path 16
[0037] For each subset of I-SID values that are mapped on the same path, the least I-SID low value is identified and all the subsets are ordered on increasing I-SID low values. The I-SID subsets are then mapped to multipoint paths identified by Group MAC addresses constructed as defined above and x:ored in accordance with IEEE std 802.1aq-2012 in increasing order. Table 2 illustrates an I-SID distribution table when addressing method (a) is used:
[0000]
TABLE 2
Exemplary mapping of I-SIDs to paths
1000, 40000, 3443
Path 1
999, 104000
Path 2
39000, 1010
Path 3
800000, 995
Path 4
[0038] An exemplary automated constructed Group MAC for a node identified by SPSourceID 5 (having the appropriate multicast address bit set) is shown in Table 3.
[0000]
TABLE 3
Exemplary automated constructed Group MAC
800000, 995
5-995
999, 104000
5-(995 x:ored 0x01)
1000, 40000, 3443
5-(995 x:ored 0x02)
39000, 1010
5-(995 x:ored 0x03)
[0039] The method described above provides a way to automate the allocation of identifiers of individual paths within ECMP multipoint path connectivity.
[0040] The address used by CFM PDUs to reach remote MEPs within the same ECMP path MA is provided by the configuration of the MA itself. In the case of the ECMP multipoint path MAs it is an SPBM Group Address associated with the monitored service. The above method describes a way to automate the distribution of Group addresses based on the I-SID ECMP configuration tables. In the case of a single path with the ECMP path MA, the CFM PDUs use the MAC address associated with it. In cases where more then one path is monitored, the CFM PDUs are cyclically destined to the associated Group MAC addresses.
[0041] The associated ECMP path MEPs are placed on a Customer Backbone Port (CBP) by using the TESI multiplex entities and using the associated Group MAC address identifiers
[0042] The techniques described above enable automated configuration of ECMP multipoint path MAs in a way that does not require alterations to existing CFM operations, and is compatible with ECMP PtP paths MAs.
[0043] Turning now to FIG. 2 , there is shown a flow diagram showing steps of an exemplary embodiment. The following numbering corresponds to that of FIG. 2 .
[0000] S 1 . ECMP multipoint paths are generated and are identified by a set of SPB Group Addresses as described above.
S 2 . ECMP PtP and multipoint path MAs are determined in order to monitor the ECMP paths. The ECMP path MAs can be associated with a connectivity path connecting a specific group of endpoints or with a subset (not necessarily proper) of equal cost paths connecting the same end points. Each ECMP PtP individual path is identified by a Flow Hash value, while each ECMP multipoint individual path is identified by an SPB Group Address as described above.
S 3 . CFM PDUs are sent and processed on those MAs determined in step S 2 . When multiple paths are used, the corresponding CFM PDUs are sent in groups cyclically on every monitored path, using the identifier associated with every monitored path. The number of CFM PDUs in every group depends on the specific CFM PDU. For example, for CCMs there should be sent at least 4 CCMs on a single monitored path before moving to the next one. For LBMs, as many LBMs as provided by the administrator that initiated the LBM are sent. For LTMs, only one LTM is sent.
[0044] As described above, there are various ways in which I-SID subsets that define paths can be mapped to Group MAC addresses.
[0045] Turning now to FIG. 3 , there is illustrated a node 5 for use in a communications network. Examples of implementations of the node 5 are any types of device that implement ECMP. This includes a VLAN aware bridge that implements IS-IS SPB and all the ECMP related functionality as described by P802.1Qbp. The node 5 may also be implemented in any device (virtual or physical), such as a router or a virtual machine, that implements the ECMP related functionality as described in P802.1Qbp.
[0046] The node 5 is provided with a processor 6 for generating the ECMP paths and applying them to data and CFM PDUs. A transmitter 7 and receiver 8 may also be provided. Note that this may be in the form of a separate transmitter and receiver or in the form of a transceiver. A non-transitory computer readable medium in the form of a memory 9 may be provided. This may be used to store a program 10 which, when executed by the processor 6 , causes the node 5 to behave as described above. The memory 9 may also be used to store tables 11 , such as Tables 1 to 3 described above for mapping I-SID values and Group MAC addresses to paths. Note that the memory 9 may be a single physical memory or may be distributed or connected remotely to the node 5 . In the example of FIG. 2 , the memory is shown as being located at the node 5 .
[0047] Note also that the computer program 10 may be provided on a further non-transitory computer readable medium 12 such as a Compact Disk or flash drive and transferred from the further memory 12 to the memory 9 or executed by the processor 6 directly from the further memory 12 .
[0048] A node such as a Bridge network node supporting ECMP can typically support a plurality of other service types (such as VLAN, Traffic Engineered services, Backbone tunnel services, etc). In an embodiment, the network is a Provider Backbone network where its edges (the endpoints described above) are Backbone Edge Bridges (which can encapsulate and decapsulate received frames) while transit Bridges are called Backbone Core Bridges which do not have encapsulation/decapsulation capabilities. The network needs to run Shortest Path Bridging in MAC mode (SPBM) which is used to create shortest paths between the edges. ECMP further updates SPBM in order to enable multiple paths among the same edges. A node performing ECMP typically has processing capabilities and requirements associated with the ECMP service monitoring. That is, ECMP MEPs need to be instantiated at the BEBs (in particular CBPs (Customer Backbone Ports within the BEBs) in order to initiate and process CFM PDUs associated with the ECMP services, and ECMP MIPs need to be instantiated at BCBs in order to process received CFM PDUs and respond.
[0049] Turning to FIG. 4 herein, there is illustrated a vessel or vehicle 13 , examples of which include a ship, a train, a truck, a car, an aeroplane and so on. The vessel/vehicle 13 is provided with the node 5 described above.
[0050] It will be appreciated by the person of skill in the art that various modifications may be made to the above described embodiments. For example, the functions of the network node are described as being embodied at a single node, but it will be appreciated that different functions may be provided at different network nodes.
[0051] The following abbreviations have been used in this specification:
BEB Backbone Edge Bridge
B-VID Bridging VLAN Identifier
CBP Customer Backbone Port
CCM Continuity Check Message
CFM Connectivity Fault Management
ECMP Equal Cost Multiple Paths
FDB Filtering Database
IS-IS Intermediate System to Intermediate System
I-SID Backbone Service Identifier
LBM Loopback Message
LTM Link Trace Message
MA Maintenance Association
MEP Maintenance Association Edge Point
OAM Operations, Administration and Maintenance
PBB-TE Provider Backbone Bridges-Traffic Engineering
PDU Protocol Data Unit
[0052] PtP Point to point
SPB Shortest Path Bridging
[0053] SPBM Shortest Path Bridging-MAC address mode
TESI Traffic Engineered Service Instance
VID VLAN Identifier
[0054] VLAN Virtual LAN | Methods and apparatus are disclosed for monitoring a Maintenance Association (MA) for Connectivity Fault Management (CFM) in a network supporting Equal Cost Multiple Paths (ECMP). A set of ECMP paths is generated for sending data between endpoints in the network. Furthermore, a set of ECMP MAs is created that are used for monitoring the generated ECMP paths between the endpoints. The created set of ECMP MAs is subsequently used for sending monitoring packets. ECMP path MAs therefore conform to existing CFM operation and are compatible with both ECMP point to point path MAs and ECMP multipoint path MAs. | 7 |
BACKGROUND OF THE INVENTION
The subject invention is directed to a welding process for drawn arc stud welding, as well as a drawn arc stud welding device for execution of the process.
In the well known drawn arc stud welding process, the part which is to be welded together with a work piece is initially placed on the work piece by means of a welding head, which can be designed as a stud welding gun. After switching on a pre-sparking or pilot current of approximately 10 to 100 A, the part is lifted off the work piece, so that a pilot electric arc is formed. Following the drawing of the pilot electric arc, the amperage is increased by a multiple up to the current level for the main current electric arc (I>100 A). After ignition of the main current electric arc, and following observance of a predetermined welding waiting time, the part is moved toward the melted work piece surface and plunged into the melted puddle. After plunging, the welding current is turned off and welding is finished.
In practical application, however, it has been shown that with stud welding, weldings of unsatisfactory quality occur particularly when there are impurities on the surfaces of the parts which are to be welded together. This involves mostly oil or grease residues on the work piece, which may, for example, be sheet plate produced by a drawing process, that is coated with a drawing lubricant.
Furthermore, similar problems occur with welding of coated, for example galvanized, parts. The presence of rust or a primer on the surfaces to be welded can likewise result in detrimental influences on the welding quality.
Therefore, it has also been known for quite some time to superimpose on the pilot arc pulses with high peak current intensities, in order to burn off impurities which may be present on the surfaces of the parts which are to be welded together (see, for example, U.S. Pat. No. 3,496,325).
It was, however, considered as a drawback, that the purification pulses were activated either manually or automatically with each welding, independent of the quality of the surfaces to be welded together.
For that reason, the control device for stud welding described in European Patent EPO 241 249 was developed. A pilot arc monitoring voltage is converted to a correction voltage by means of a set-point comparator and is superimposed on a control voltage for principally controlling a high-frequency modulated switching mode power supply unit, in accordance with the thus corrected control voltage, that adjusts its output current during the respective welding operation to the resistance value of the pilot arc as established by the monitoring voltage. In this fashion, recognition of the quality of the surfaces to be welded is achieved through measuring of the voltage of the pilot arc (as was already known from German Patent 3130389C2). Thereafter, cleaning of surfaces can be obtained through an increase of the pilot current for a given period of time.
This process in essence is based upon the teaching from German Patent 3130389C2, that a heavily soiled, for example greasy surface, exercises a clearly measurable influence upon the voltage of the pilot arc, while the voltage of the main current electric arc remains practically unaffected thereby.
Since with these known welding processes the attained quality of the finished welding is to be appraised based on the voltage of the pilot arc, relative uncertainty results in the evaluation of the obtained welding quality, inasmuch as it is true that inadequately prepared or soiled surfaces are being recognized, but it is not possible to control the actually achieved improvement through altering of the welding current (pilot current--and/or the main current electric arc) and/or the activation of purification pulses.
Proceeding from the above-discussed state of the art, the invention is based on the objective to create another welding process for drawn arc stud welding, which makes it possible to recognize inadequately prepared surfaces to be welded and which reduces, through appropriate measurements, their impact upon the quality of the finished welding. In addition, the invention is directed to a device for the execution of the process.
SUMMARY OF THE INVENTION
Inadequately prepared or soiled surfaces are identified in the process according to the invention by measuring the voltage of the main current electric arc. The impact of such surfaces upon the finished welding is reduced through appropriate control or regulation of the current flow of the main current electric arc.
The invention proceeds from the knowledge, contrary to the previously held opinion (German Patent 3130389C2), that inadequately prepared or soiled surfaces also exercise an influence on the voltage of the main current electric arc, to an extent that the same can be reliably measured by test methods and evaluated according to the invention.
In one specific embodiment of the invention, the mean voltage over a brief time interval is measured immediately after the ignition of the main current electric arc, and dependent thereon, the current flow of the continued main current electric arc and/or the plunging movement of the parts which are to be welded, are regulated or controlled.
Taking a measurement of the mean voltage results in the advantage of higher accuracy and reproducibility of the measured value. Needless to say, in taking such measurements, the time interval during which the mean voltage is determined, for instance through scanning of voltage in equal intervals, must be short enough so that there remains sufficient time for influencing the continued main current electric arc, without, however, excessively high welding times resulting therefrom.
In the preferred specific embodiment of the invention, an initially predetermined flow of the main current electric arc is altered upon exceeding or failing to reach a predetermined threshold voltage value, through measuring of mean voltage. The change of the initially predetermined flow is preferably made dependent upon the deviation rate of mean voltage from the previously set threshold voltage value.
In the preferred specific embodiment of the invention, upon exceeding the threshold voltage, the main current is increased by an adequate amount for the duration of a purification pulse with steep pulse flanges (positive pulse) or reduced (negative pulse) or initially reduced, subsequently increased to a higher value in comparison with the initial value, and at the end of the period, the negative/positive purification value is reduced once again to the initial value, in order to bring about by the thereby produced excess voltage, a purification of the surfaces which are to be welded together. In so doing, it turned out that a positive edge of the welding current is particularly suitable for cleaning the surfaces which are to be welded together.
Instead of the negative/positive pulse, a positive/negative pulse can also be employed, where the current is initially increased, subsequently lowered and finally increased again to the initial value.
After generating a purification pulse, the mean voltage of the main current electric arc is preferably measured once again in order to determine whether the desired cleaning effect was attained in adequate measure. If an excessively high mean voltage of the main current electric arc is detected, the same as before, the process of generating a purification pulse with subsequent renewed control of the main current electric arc voltage is repeated until the mean measured voltage is below the threshold voltage value or until a previously determined number of purification pulses has been reached.
This process guarantees the benefit that the energy contents of a single purification pulse, even with heavily soiled surfaces, can be kept relatively small. An excessive impairment of the flow of the main current electric arc or the welding process can thus definitely be avoided.
If the predetermined number of purification pulses has been reached, with the mean voltage of the main current electric arc, measured after the last pulse, positioned below the pre-established threshold voltage value, then the welding process is preferably continued, inasmuch as based on the initially already relatively high current of the main current electric arc, a melting start of the surfaces which are, to be welded together has already taken place.
Additionally, in cases like this, a warning signal can be produced, or the welding process can be recorded with a corresponding error registration. This results in the advantage that with welding on the same work piece, or with comparable work pieces, appropriate statistical data can be obtained through simple evaluation of the protocol, and, separately from this, suitable measures can be undertaken such as pre-cleaning of surfaces or changes in the welding parameters. The protocol, naturally, can also be kept by memory storage of measured values or data derived from said values.
In one specific embodiment of the invention, in order to achieve the highest positive edge, it is possible automatically select either a positive or negative purification pulse, whereby a positive purification pulse is produced if a pre-set initial main welding current lies below a predetermined value, and a negative purification pulse, if the predetermined initial main welding current lies above a predetermined value.
A negative/positive or a positive/negative purification pulse can, needless to say, also be employed independent from an initial main welding current. Thereby, the bottom current value, with a positive/negative purification pulse, is limited by the bottom limitation of the range for the main welding current of the main welding current source, which frequently is designed separately from the current source for generating the pilot arc current.
In the preferred specific embodiment of the invention, the flow of the main current electric arc is corrected subject to the number and the positive or negative energy contents of the purification pulses and, if necessary, energy contents contained in time segments between two purification pulses. This will guarantee that the energy contents of the actually executed welding process will not exceed, or fall short of, in an excessively high manner, the energy contents according to the originally pre-set welding parameters and/or the preset welding curve.
In the simplest case, correction can be made in that the amperage of the main current electric arc, following completion of the purification pulses, with constant duration of the main current electric arc, is increased or lowered, or the duration of the main current electric arc, with constant current intensity of the main current electric arc, following completion of the purification pulse, is lengthened or shortened.
In one specific embodiment of the invention, the main current electric arc, by taking a single or multiple measurement of the mean voltage can be ignited by means of a constant initial current intensity, which is independent of the subsequent current intensity of the main current electric arc. This results in the benefit that with fixed ceiling--and/or bottom limitations for the current intensity of a purification pulse, there is produced the same height of pulse edge, which, essentially, is responsible for the intensity of the cleaning effect. In addition, there is the advantage that the threshold voltage need not be adapted to varying initial current intensities of the main current electric arc, which, basically, would be possible, for instance through the employment of an appropriate characteristic curve.
In the preferred specific embodiment of the process according to the invention, there is derived, from the deviation of the last measured mean voltage of a nominal voltage, a value or, in general, some information relative to the quality of the finish welding.
This results in the benefit that following execution of surface cleaning, the effectiveness of this measure can be checked and insofar as other known processes are concerned, a more reliable statement can be made regarding quality of the finished welding.
Said value is preferably shown on a display which is visible to the operator of the welding apparatus. Naturally, it can also be recorded instead or in addition as a value pertaining to the respective welding.
Additional specific embodiments of the invention result from the dependent claims.
Still other advantages and benefits of the invention will become apparent to those skilled in the art upon a reading and understanding of the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention may take physical form in certain parts and arrangements of parts, a preferred embodiment and method of which will be described in detail in this specification and illustrated in the accompanying drawings which form a part hereof, and wherein:
FIG. 1 is a schematic illustration of a stud welding device;
FIGS. 2a-2b are diagrams with curves showing the welding current and the arc voltage during welding, pursuant to a first specific embodiment of the welding process in accordance with the invention; and
FIGS. 3a-3b are diagrams with curves showing the welding current and the arc voltage during welding according to another specific embodiment of the stud welding process in accordance with the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings wherein the showings are for the purposes of illustrating the preferred embodiment of the invention only and not for purposes of limiting same, the stud welding device 1, illustrated in FIG. 1 is comprised of a control apparatus 3 connected with a stud welding head 5 which, as shown in FIG. 1, can be designed as a stud welding pistol of any of a variety of known types.
The stud welding head 5 has in its anterior region a stud holder 7, in which is held a stud 11, which is to be welded to a work piece 9, and which is connected with a first electrode 13, supplying welding current. The stud holder 7 with stud 11 held therein, is arranged within a cylindrical pipe 15, which on the one hand serves as a limit stop for positioning the weld head 5 on the surface of the work piece 9, and, on the other hand serves as a guard against contact with the electrically live components.
For execution of a stud welding process according to the drawn arc stud welding process, the stud, after placement of welding head 5 on the surface of the work piece 9 and switching on of pilot welding current I, is lifted off the work piece surface by means of the stud holder 7, so that an electric arc with relatively low intensity (Up to approximately 100 A)--the so-called pilot arc--is drawn. For supplying the pilot welding current I, the stud welding head 5, designed in form of a stud welding gun has a trigger 17, which closes, for example, a switch (not shown). The closing of the switch is detected by a current supply and control unit 19 of control apparatus 3, via control lines (not shown) between the stud welding head 5 and the control apparatus 3.
After detecting the start signal for a stud welding process, the stud holder 7 with stud 11 is lifted off work piece 9 by means of a solenoid 21 arranged in the stud welding head. To that end, the current supply and control unit 19 is connected with the stud welding head via connecting lines 23.
Prior to activating the solenoid 21 by the current supply and control unit 19, immediately after generating the starting signal S, the pilot current I is switched on by the trigger 17. Current I initially flows from the current supply and control unit 19 through a path including first electrode line 25, stud 11, work piece 9, second electrode line 27, and back to the origin of the current supply and control unit 19. This generation of the pilot arc thus occurs in known fashion.
The current supply and control unit 19 of the control apparatus 3 comprises all necessary components for generating, controlling and regulating the welding current. In addition, the current supply and control unit 19 contains, needless to say, components for setting and storing of welding parameters, welding curves and when necessary, a memory for the registration of data concerning one or several welding processes.
In addition, the control apparatus 3 includes a measuring and control unit 29, for taking measurements of and for evaluation of the U-voltage of the arc during a welding process, which homes in on the current supply and control unit 19 in the subsequently described manner and which cooperates with same. In the simplest case, for measuring of the electric arc voltage, the U-voltage can be collected at the origin of the current supply and control unit 19, connected via electrode lines 25 and 27, and can be supplied to the measuring and control unit 29. In this instance, the measuring and control unit 29 can naturally also measure the U-voltage at times outside of a welding process, so that in this manner hazardous voltages and voltages caused by malfunction of the apparatus, can be detected by the operator. In such case, the measuring and control unit 29 can home in on the current supply and control unit 19, so that an emergency shut-off of the entire control apparatus 3 will occur, or at the very least, a shut-off of the welding start of the current supply and control unit 19.
The task of the measuring and control unit 29 begins only after the initial main welding current I has been on longer than time t v , in other words after expiration of the pilot time, or after the start of the main welding process (FIG. 2a or FIG. 3a).
After turning on the main current electric arc with the initial main welding current I, and after waiting for a response time, during a measuring time interval `Delta t m `, a measurement is taken of the relevant voltage U of the main current electric arc. In order to increase the measuring accuracy and to improve the reproducibility of the measurement taking, the voltage is averaged U avg during the measuring time interval `Delta t m `. Inasmuch as it is necessary in order to evaluate the measured voltage U to carry out an analog/digital conversion of the measured voltage values, by means of a customarily employed microprocessor, the formation of the mean voltage through scanning of voltage U of the main current electric arc can be done in several equally spaced time intervals and the average value can be established through simple mathematical operations by the microprocessor.
Since the path of the electric arc is to be influenced independent of the measured voltage values, and since the entire main welding process from start of the main current electric arc until the plunging of the stud into the melted area of the work piece lasts only a few milliseconds to some 10 milliseconds, the current supply and control unit 19 must have a welding current source which will guarantee upon switching on the main welding current I or when changing the main welding current I, an extremely high edge steepness.
Inasmuch as the voltage U of the main welding electric arc, according to the knowledge on which the invention is based, permits reaching a conclusion with respect to the surface condition of the parts that are to be welded together, specifically with respect to the work piece, it is possible, following the first initial measurement of the voltage of the main current electric arc U, to adapt the continued main welding process, through targeted influence upon the main welding current I, to the surface conditions of the work pieces which are to be welded together.
Thus, for instance, with upward deviation of actual voltage U of the main current electric arc from a pre-set threshold voltage value U s , the welding time t s can be extended and/or the main welding current I increased, since, in comparison to a case of ideally prepared surfaces, the increased voltage U of the main current electric arc points to contamination of surfaces or coating of surfaces.
Likewise, with falling short of a threshold voltage adapted to average permissible contamination, there may also be a shortening of the welding time t s and/or delay in the main welding current.
Naturally, measurement of the main current electric arc can be repeated several times or can take place quasi-continuously and subject thereto, the current intensity and/or the duration of the main current I electric arc or the current path of the current intensity can be altered.
With the preferred specific embodiment of the process according to the invention pursuant to FIG. 2, when detecting vis-a-vis a threshold voltage U s , an increased voltage (average voltage) a purification pulse can be superimposed on a pre-set course of the main current electric arc. To that end, as indicated in FIG. 2a, immediately after completion and evaluation of measurement taking of voltage U of the main current electric arc, the main welding current I with an extremely steep edge is increased after its start, to an extremely high value, preferably to the maximum value I max which can be supplied by the current supply source (or the pre-set subsequent higher welding current at the welding apparatus), and thereafter immediately brought again down to an initial value I h of the main welding current I. In so doing, the steep edges, specifically the positive edges of the purification pulses produce an excess voltage, which scatters, explosion-like, in all directions, the dirt particles which are present on the surfaces.
FIG. 2b indicates that after completion of the first purification pulse, the measured average voltage of the main current electric arc U, which was again taken during a subsequent time interval `Delta t m `, did, in fact decline compared with the originally measured value, but still lies above the pre-set threshold voltage value U s . With the illustrated welding process, the conclusion can be reached that the surfaces, which are to be welded together still have an excessively high dirt level.
Accordingly, after the second measurement of voltage U of the main current electric arc, a new purification pulse is ignited.
During the third measuring of the voltage U of the main current electric arc, which was done after the above purification pulse, adequate surface quality was detected, since the measured voltage was below the threshold voltage U s . Thus, the remaining portion of the main welding process could be continued and completed with the higher current intensity illustrated in FIG. 2a. This increase of the main welding current intensity, done only after completion of any required purification pulses, has the advantage in that during the time when the surfaces are being cleaned, there will take place only minor melting of the surfaces, as a result of which, impurities can be more easily removed by the excess voltage of the purification pulses than when the impurities have already been trapped in the melted mass.
The superimposition of purification pulses is preferably terminated if, as illustrated in FIG. 2, the voltage U of the main current electric arc, measured after the last purification pulse, lies below the pre-set threshold and/or if a pre-established maximum number of purification pulses has been reached. In the latter case, the welding process is preferably completed even if the last measured voltage of the main current electric arc still lies above the pre-set threshold since interruption of the welding process may result in difficulties when undertaking a new welding process. Moreover, despite the measured "impermissibly high" voltage value of the main current electric arc, there might be produced a welding with adequate stability.
Taking measurement of the voltage after completion of the last purification pulse has the advantage, compared with known processes, that the cleaning effect of the pulses can actually be checked and thus there is a higher accuracy in the statement regarding the quality of the finished welding.
As indicated in FIG. 3, the purification pulse can naturally also be carried out in that instead of the positive purification pulses shown in FIG. 2a, the current of the main current electric arc is at first lowered from an initial value I h to the lowest possible value I min , subsequently, it is immediately increased to a maximum possible value of I max and after that, it is again reduced to the initial value. As a result of such negative/positive purification pulses, the advantage of a significantly higher positive edge is achieved, which contributes to a higher excess pressure and thus to a better cleaning effect. It is also possible to employ a purely negative cleaning pulse or a positive/negative cleaning pulse (at first increase to a higher, then reduction to a lower and finally return to the original value). It turns out, however, that a positive edge with a maximum possible height has achieved better cleaning effect vis-a-vis an equally high negative edge.
Since in the welding process illustrated in FIG. 3, the voltage U measured after the single purification pulse of the main current electric arc, was already below the pre-set threshold voltage U s , it was possible to complete the welding process without performing additional purification pulses.
Inasmuch as both through the purification pulses (at least during their positive segments) as well as during the time intervals `delta t m `, compared with a welding process where no cleaning pulses or measurement-taking is performed, the main current electric arc is supplied with additional energy, this circumstance is taken into consideration during the following part of the welding process, by providing corresponding correction. To that end, there exists for instance the opportunity to determine the additional energy compared with a welding process without purification pulses (only one single measurement is needed for the main current electric arc voltage during a one time interval `delta t m `), up to completion of the last measurement-taking of the main current electric arc voltage and, on the basis thereof, to influence the further course of the main welding process.
In the simplest specific embodiment, the further course of the main welding process could, for example, be influenced in such a way that the energy contents of the actually performed welding process would basically agree with the energy contents of an ideal welding process or would only be slightly higher, since a given energy content was necessary for the removal of the impurities. The energy content of the ideal welding process could for instance be ascertained by calculation of the energy content of a welding process without a purification pulse, in such manner that the ideal current course (which is maintained through control of the welding current) is multiplied with the ideal voltage course, and from said chronological course of performance, the energy contents is determined through integration.
By way of the voltage course, the first measured voltage value can be determined, taking into account the known functional dependency of the welding voltage upon welding current, or, the voltage can be continuously measured with the measuring and control unit 29.
In the simplest case, the additional energy content which was ascertained in the above described manner, can be corrected by reduction or extension of welding time or by increasing or lowering the main welding current to the remaining welding time or any combination of the above.
Thus, the invention provides, with minor hardware expense, a realizable possibility for automatic adaptation of welding parameters or of the entire welding process to varying conditions of surfaces that are to be welded together.
The invention has been described with reference to the preferred embodiment. Obviously, modifications and alterations will occur to others upon a reading and understanding of this specification. It is intended to include all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof. | The invention relates to a welding process for drawn arc stud welding wherein after ignition of the main current electric arc, the latter's voltage (U) is measured and, depending upon the measured voltage, the current flow of the continued main current electric arc and/or the dipping movement of the parts which are to be welded together, is regulated or controlled. | 1 |
FIELD OF THE INVENTION
The present invention relates to range hood motor housings, and more particularity to an improved motor housing design.
BACKGROUND OF THE INVENTION
Range hoods are used above cooking surfaces to remove grease, common odors and hazardous gases created during the cooking process. Typically, range hoods for domestic use have a pair of motors horizontally installed in a motor housing within the hood body. Each motor drives a fan. The fans draw air from the cooking area below and force it through the motor housing to ventilation piping.
The motor housing defines an enclosure and is mountable within a further enclosure formed by the range hood body. The side walls of the motor housing are substantially vertical and when viewed from above or below appear to generally define a figure-eight pattern. The interior of the housing is separated into two substantially similar, separate chambers. Each chamber has an air inlet and a ventilation hole.
The heated air drawn from the cooking area generally contains some vaporized grease. As the air is forced through the motor housing, some of the grease condenses and is deposited on the inside surfaces of the motor housing. The motor housing is generally shaped to funnel the condensed grease to the bottom of the housing, eventually draining to an external grease cup. However, because the grease is airborne it is therefore important to ensure that the housing is completely sealed, to prevent the grease from escaping into the main range hood body. It is also desirable to be able to access the motor housing interior in order to clean it.
U.S. Pat. No. 5,537,988 shows a typical motor housing constructed using a single piece of metal, suspended from the underside of the range hood body and welded in place. Because the motor housing cannot be removed or disassembled, a person must clean the motor housing by reaching up through the fan opening. The person is working “blind” inside the housing, which makes it difficult to thoroughly clean. Also, a non-metallic motor housing cannot be welded in place on the range hood body. Use of a plastic motor housing, for example, would result in an imperfect seal between the motor housing and range hood thereby allowing grease to escape into the main range hood body.
Another type of motor housing is made from an upper section and a lower section, joined by welding the sides together. The entire housing and the motors are then connected to the range hood body. This construction is difficult and expensive, as it requires careful folding of the metal and expensive welding. Again, the housing cannot be disassembled and is therefore difficult to clean. Furthermore, this form of connection cannot be used for a plastic motor housing as folding and welding of plastic is not an option.
It is therefore an object of the present invention to provide a range hood having a motor housing that may be snugly sealed, preventing condensed grease from escaping into the main range hood body.
It is a further object of the present invention to provide a motor housing for a range hood that may be made of metallic or non-metallic material.
It is a further object of the present invention to provide a motor housing for a range hood that can be easily disassembled and reassembled, to facilitate thorough cleaning and access to the motor housing interior.
Not all aspects of the invention necessarily address each of these objects. Other objects of the invention will be apparent from the description that follows.
SUMMARY OF THE INVENTION
According to the present invention there is provided a motor housing for a range hood. An upper section of the motor housing is snugly joined around its outer edge to a lower section of the motor housing, thereby forming the perimeter side surfaces of the motor housing. The upper and lower sections are snugly joined by inserting the top edge of the lower section into a gap in the lower rim of the top section.
In one aspect the invention comprises a motor housing for mounting within a range hood body used to exhaust gases from above a cooking surface. The motor housing comprises an upper section having a top surface and a first side perimeter surface extending away from the top surface. A lower section having a bottom surface and a second side perimeter surface extends away from the bottom surface. The edge of one of the first or second side perimeter surfaces has cooperating projections with a gap therebetween. The edge of the other of the first or second side perimeter surfaces is adapted to be inserted in the gap between the cooperating projections to be frictionally retained therein.
In another aspect, the first side perimeter surface has the cooperating projections and the edge of the second side perimeter surface is adapted to be inserted in the gap between the cooperating projections to be frictionally retained therein.
In yet a further aspect, the motor housing further comprises a plurality of protrusions on the second side perimeter surface. The protrusions may be spaced from the edge of the second side perimeter surface a maximum distance equal to the depth of the gap between the cooperating projections.
In yet a further aspect, the motor housing further comprises a reinforcing assembly. The reinforcing assembly may take the form of a reinforcing strap and a fastening means. The fastening means comprise a pair of aligned fasteners, one on each section of the motor housing, to which the reinforcing strap may be connected. The fasteners could take the form of a pin and cotter pin, a self-locking pin such as a snap-fit pin, or a bolt and nut. A plurality of reinforcing assemblies may be spaced about the perimeter side surface of the motor housing.
The foregoing was intended as a broad summary only and of only some of the aspects of the invention. It was not intended to define the limits or requirements of the invention. Other aspects of the invention will be appreciated by reference to the detailed description of the preferred embodiment and to the claims.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other features of the invention will become more apparent from the following description in which reference is made to the appended drawings and wherein:
FIG. 1A is a side sectional view of a kitchen range hood, including the preferred embodiment of a motor housing according to the invention, with the right hand portion of the figure providing a deeper sectional view than the left hand portion of the figure;
FIG. 1B is a side section view of a kitchen range hood, including an alternative embodiment of a motor housing according to the invention, with the right hand portion of the figure providing a deeper sectional view than the left hand portion of the figure;
FIG. 2 is a bottom perspective view of the preferred embodiment of the motor housing;
FIG. 3A is an enlarged view of the joint between the upper and lower sections of the motor housing of FIG. 2;
FIG. 3B is an enlarged exploded view of the joint between the upper and lower sections of the motor housing of FIG. 2;
FIG. 4 is a bottom perspective view of an alternate embodiment of the motor housing;
FIG. 5A is an enlarged view of the joint between the upper and lower sections of the motor housing and the reinforcing assembly of FIG. 4;
FIG. 5B is an enlarged exploded view of the joint between the upper and lower sections of the motor housing and the reinforcing assembly of FIG. 4;
FIG. 6A is an enlarged view of the joint between the upper and lower sections of the motor housing and an alternate embodiment of the reinforcing assembly of FIG. 4;
FIG. 6B is an enlarged exploded view of the joint between the upper and lower sections of the motor housing and an alternate embodiment of the reinforcing assembly of FIG. 4;
FIG. 7A is an enlarged view of the joint between the upper and lower sections of the motor housing and a further alternate embodiment of the reinforcing assembly of FIG. 4; and
FIG. 7B is an enlarged exploded view of the joint between the upper and lower sections of the motor housing and a further alternate embodiment of the reinforcing assembly of FIG. 4 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIGS. 1A and 2 show a range hood 10 comprising a range hood body 12 in which a motor housing 42 according to the preferred embodiment of the invention is mounted.
Range hood 10 is designed to be mounted above a home cooking surface, such as a four-burner stove, in order to facilitate the removal of grease laden vapors and the like generated while cooking. The motor housing 14 has top section 16 , bottom section 18 and perimeter side surfaces 20 which define an enclosure 22 and is mountable within a further enclosure 24 formed by the range hood body 12 . The motor housing 14 may be made of metal or a non-metallic material such as plastic. The interior of the housing 14 may be coated with a non-stick material so as to facilitate grease removal.
The assembled housing 14 comprises two chambers (only one of which is visible in FIG. 1 A), each accessible through an air inlet 26 in the underside of the housing 14 . A motor 28 is fitted in each chamber of the housing 14 and is attached to the inside of the upper surface of the range hood body 12 . A fan 30 is secured to each of the motors 28 by fan caps 32 . Fan grill 34 connected to lower panel 36 prevents foreign objects from being inserted through air inlet 26 and into the fan 30 . Lower panel 36 is releasably connectable to the rest of range hood body 12 . When the motors 28 are In operation, each fan 30 rotates and acts to draw grease-laden air through air inlet 26 and into the motor housing 14 where it is forced out the ventilation hole (not shown).
FIG. 3A shows an enlarged view of the joint between the upper section 16 and lower section 18 of the motor housing 14 , while FIG. 3B is an exploded view of the same joint. Cooperating projections 40 at the free end of the side wall of the upper section 16 forms a y-shaped gap within which the outer edge 42 of the side wall of the lower section 18 may be inserted. Cooperating projections 40 are angled inward at the tips of the Y to provide guidance and ensure proper insertion of edge 42 . The gap between the cooperating projections 40 is sized to correspond to the thickness of edge 42 , in order to provide a snug friction fit between the pieces. It will be understood that the exact shape of the joint ends is not critical, as long as the edge fits snugly into the gap.
Preferably alignment pins such as protrusions 44 are spaced at intervals about the perimeter of the motor housing 14 , as shown in FIG. 2 . In the preferred embodiment, the alignment pins 44 are positioned on the outside surface of the edge 42 to provide guidance as to how far the two housing sections 16 , 18 have to be pushed together to ensure a tight fit. The sections are pushed together until the outer one of the cooperating projections 40 abuts alignment pins 44 . The alignment pins 44 also provide a visual guide, allowing visual inspection of the housing to ensure it is properly reassembled. Therefore the maximum distance the alignment pins 44 may be spaced from the edge 42 is equal to the depth of gap 40 .
For simplicity, the description and drawings treat the gap 40 of the joint as extending downwardly from the upper section 16 of the housing 14 , while the top rim of the lower section 18 forms the edge 42 . This is preferred so that any grease draining down the interior of the motor housing does not drain into the gap. However, it will be understood that the joint directions may also be reversed.
Lower section 18 may include a drainage hole in the bottom (not shown). Preferably, lower section 18 has a wall 6 projecting into the chamber and defining an air inlet. When grease funnels to the bottom of the motor housing 14 , wall 6 prevents it from draining through the inlet opening. Instead, the bottom surface of the motor housing is sloped so that the grease drains to the drainage hole and through a hose 58 , where it collects in a grease cup 60 . Grease cup 60 extends below range hood 10 , where it is easily accessible and may be emptied without disassembling the entire range hood.
Tray 4 may be inserted in a gap formed between a downwardly extending projection 8 and wall 6 . The tray acts to direct airflow into the fan and also acts to catch any grease that may drip off the outer circumference of the fan 30 . This tray is releasably connectable to the motor housing allowing easy access to the fan.
In the alternative embodiment shown in FIG. 1A, no tray is present. Because the lower section 118 is removable for cleaning, it is unnecessary to attach a separate tray to the motor housing. Wall 106 depends from lower surface 104 forming an air inlet and acting as a barrier to grease collecting within the housing. Wall 108 in lower panel 36 forms an air inlet and when panel 36 is connected to the hood body 12 of the range hood 100 , wall 108 and wall 106 are in abutment. Since no special fabrication is required to attach a tray to the lower section 118 , lower section 118 may be a simpler piece, decreasing engineering and fabrication costs. However, not having a tray leads to a more involved process to access one of the fans as discussed further below. It is also contemplated that the lower section of the motor housing could be adapted to connect with the tray types of the prior art.
To fully stabilize the joint and provide extra sealing, a sealant such as silicon may be inserted into the gap 40 before the edge 42 is inserted. In order to access the interior of the motor housing and clean out any accumulated grease, it may be desirable to remove the lower section 18 of the motor housing 14 . If the lower section 18 is to be removable, no sealant will be added to the joint prior to assembly of the upper and lower motor housing sections 16 , 18 .
While the friction fit of the joint provides a firm connection of the two motor housing sections, it is also contemplated that further restraints may be incorporated to prevent unwanted separation of the two sections. Such a restraint is shown in an altemative embodiment of the invention is illustrated FIG. 4 . The restraints provide extra support for the motor housing 14 , to ensure that the upper and lower sections 16 , 18 of the housing 14 stay firmly locked in place. Restraints such as reinforcing assemblies may therefore be placed at intervals around the perimeter of the housing 14 , as shown in FIG. 4, and in greater detail in FIGS. 5-7.
Generally, a reinforcing assembly comprises a pair of reinforcing pins 46 integral to the outer surface of the upper and lower sections 16 , 18 of motor housing 14 , and a reinforcing strap 48 with holes 49 . In the preferred embodiment of the invention, shown in FIGS. 5A and 5B, the holes 49 in the reinforcing strap 48 slide over the pins 46 . The reinforcing strap 48 is then locked into place by insertion of cotter pins 50 , or a similar locking mechanism such as a cable tie or twist tie, into grooves in reinforcing pins 46 . It is contemplated that the reinforcing strap could be made of fabric, metal, plastic or any other suitable material that is heat resistant and non-stretching.
In an alternate embodiment, shown in FIGS. 6A and 6B, reinforcing pins 46 may be replaced by self-locking snap-fit pins 52 . The snap-fit pins 52 lock into place once reinforcing strap 48 is attached. Pressure must be exerted against the snap-fit pins in order to disconnect the strap 48 .
In a further alternate embodiment, shown in FIGS. 7A and 7B, bolts 54 may also be used to hold reinforcing strap 48 in place. Nuts 56 cover the exposed ends of the bolts 54 , protecting users from injury and providing esthetic appeal.
In all embodiments, if the motor housing 14 is made of metal, the fastening means (fasteners such as pins 46 , 52 or bolts 54 ) will preferably be welded onto the side of the upper and lower housing sections 16 , 18 . If the housing 14 is made of plastic, the fastening means will preferably be molded and integral to the housing sections 16 , 18 . Such fabrication will provide the strongest fastening means to reinforce the connection between upper section 16 and lower section 18 .
To access the motor housing 14 for cleaning, it is necessary to remove lower panel 36 . After disconnecting hose 58 lower section 18 may be pulled straight down in order to separate it from upper section 16 , and out of the range hood 10 . Lower section 18 may then be cleaned. The cleaning person also has direct access to the entire underside of upper section 16 . The fan may also be easily removed to facilitate cleaning. The motor housing may be reassembled simply by lining up the edges of motor housing sections 16 , 18 and pushing the two halves of the housing 14 together until the cooperating projections 40 meet alignment pins 44 . It may also be advisable to complete a visual inspection, to ensure that the halves are completely and properly joined before reattaching the hose 58 and finally, lower panel 36 .
Should access to only one fan be required, one need simply remove the lower panel 36 and tray 4 . This may be preferable for minor cleaning of the motor housing interior.
If the motor housing is equipped with any of the reinforcing assemblies discussed above, these must be unfastened prior to pulling lower section 18 down to separate it from upper section 16 of the motor housing 14 . To reassemble the motor housing 14 , motor housing sections 16 , 18 are first re-joined then the reinforcing assemblies are fastened. The reinforcing assemblies also provide a check to ensure the two sections 16 , 18 are firmly in place, since reinforcing straps 48 will not fit over the pins unless the motor housing 14 has been reassembled properly.
It will be appreciated by those skilled in the art that the preferred and alternative embodiments have been described in some detail but that certain modifications may be practiced without departing from the principles of the invention. | A range hood with a motor housing having upper and lower sections joined together along their respective side edges. Cooperating projections with a gap therebetween extend from the side edge of one section of the motor housing. The side edge of the other section of the motor housing is adapted to be Inserted in the gap to be frictionally retained therein. Protrusions ensure proper joining of the upper and lower sections. Additional restraint in the form of a reinforcing assembly comprising a reinforcing strap plus fasteners ensures the upper and lower sections stay properly joined. The motor housing may be made of metal or plastic. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a transmission line system that is optimized for low loss. More particularly, the invention relates to a transmission line system and a connector for communicating a coaxial cable of one impedance with a device of another impedance with low losses.
2. Description of the Related Art
A communication industry transmission standard is a 50 ohm impedance for communication systems. A 75 ohm coaxial transmission cable, however, has lower attenuation characteristics and a higher operating frequency than a 50 ohm coaxial transmission cable, thus making the 75 ohm transmission cable a better choice for some broadcast applications and CATV industries. To employ a transmission cable with higher impedance, broadcast systems may require separate matching transformers to convert the impedance back to a typical 50 ohm device and CATV systems require 75 ohm mating connectors and amplifiers to integrate the 75 ohm cables into the respective systems. One specific application is the use of telecommunication cables in the PCS band for mobile telephones. The frequency band for this service is 1850 to 1990 MHz in the United States. This band involves very high frequencies, but not high enough to justify the cost of waveguides or tower loading to lower the attenuation. Therefore, a system is desired that reduces signal loss while having low product and implementation cost.
SUMMARY OF THE INVENTION
The present invention is directed to a communication system comprising a signal on a coaxial transmission line which provides lower attenuation given the frequency of the signal, and a mating connector. The connector includes an integral connector transformer with optimized impedance for matching a low loss cable such as the 70 ohm coaxial transmission line to 50 ohm devices through an interface. The 70 ohm transmission cable typically includes low-density foam and a smooth hollow tube center conductor. A corrugated tube or solid wire could be used depending on the overall diameter of the cable. The outer conductor of the cable is typically made of an annular corrugated copper tube configured to simplify connector installation and provide flexibility. Other designs for the outer conductor are possible, designs such as smooth or helical corrugations. The connector includes means for attaching the connector to the cable as will be discussed further.
In one embodiment, the connector comprises an integral quarter wave transformer designed for the desired frequency of operation and standard means of attaching the connector to cable conductors by providing electrical contacts. In another embodiment, there is a series quarter wave open circuit inner stub that capacitively couples to the hollow center conductor of a coaxial transmission line, along with an integral transformer. Alternatively, the stub is reversed for a solid center conductor with a hollow center conductor of the connector. In yet another embodiment, there is an integral transformer and a series quarter wave open circuit outer stub that capacitively couples to an outer conductor of a coaxial transmission cable. Additionally, there is an embodiment which includes both a series quarter wave open stub inner conductor, a series quarter wave outer conductor, and an integral quarter wave transformer.
The use of the series quarter wave open stub conductors and the integral transformer provide additional tuning to allow a wider frequency band of operation and still have a Voltage Standing Wave Ratio, or VSWR, of less than 1.02:1.
BRIEF DESCRIPTION OF THE DRAWINGS
Other features and advantages of the present invention will be apparent from the following description taken in connection with the accompanying drawings, wherein:
FIG. 1 is a cross sectional view of an embodiment of the invention using a connector coupling design incorporating an integral quarter wave transformer;
FIG. 2 is a cross sectional view of an embodiment of the invention showing a series open circuit outer stub;
FIG. 3 is a cross sectional view of an embodiment of the invention showing a series open circuit outer stub disposed inside the outer conductor of the coaxial transmission line;
FIG. 4 is a cross sectional view of an embodiment of the invention showing a series open circuit inner stub;
FIG. 5 is another configuration of the series open circuit inner stub;
FIG. 6 is a cross sectional view of an embodiment of the invention comprising a series open circuit outer and inner stubs; and
FIG. 7 is a cross sectional view of an embodiment of the invention showing series open circuit outer and inner stubs, and an outer conductor choke.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
An exemplary first embodiment will now be described with reference to the drawings. A cross sectional view of a frequency selective low loss coaxial electrical connector 100 is shown in FIG. 1 . The connector 100 is used to connect a first coaxial transmission line 180 with a first impedance to an electrical device (not shown) with a second impedance. By way of example, the first coaxial transmission line 180 has an impedance of 70 ohms and the electrical device is a second coaxial transmission line with the communication industry standard impedance of 50 ohms. The impedance of coaxial transmission line 180 is selected to provide the minimum attenuation depending on the construction and material used. It is noted that the first coaxial transmission line 180 and the electrical device can take on different impedance values than the ones above.
First coaxial transmission line 180 includes a typically smooth hollow tube center conductor 182 A surrounded by an insulation 184 with a dielectric constant ∈ 1 . The insulation 184 is made of any suitable dielectric, including, for example, solid polyethylene, foamed polyethylene, Teflon (polytetrafluoroethylene), fluorinated ethylene propylene, and foamed fluorinated ethylene propylene, or any material in combination with air. The choice of material and final foamed density will determine the dielectic constant and, therefore, the impedance that provides the lowest attenuation for a given size cable. The dielectric provides support to maintain the inner conductor on the axis of the cable. Surrounding the insulation 184 is an outer conductor 186 . The outer conductor 186 is typically made of an annular corrugated copper sheet to provide flexibility and ease in attaching standard connectors. Surrounding the outer conductor 186 is a protective cover 188 .
First coaxial transmission line 180 is coupled to the connector 100 . The connector 100 comprises a substantially cylindrical body 200 having a spaced first end portion 210 , second end portion 220 , and an elongate center portion 230 including a transformer section 700 . It is noted that the substantially cylindrical body 200 is electrically conductive. The elongate center portion 230 is disposed between the first end portion 210 and the second end portion 220 , and has an axial bore 240 therethrough. Additionally, there is a dielectric bead 250 with a dielectric constant ∈ 2 fixed inside the axial bore 240 at an end of the center portion 230 . As with the insulation 184 of the first coaxial cable 180 , the dielectric bead 250 is made of any suitable dielectric, including, for example, solid polyethylene, foamed polyethylene, Teflon, fluorinated ethylene propylene, and foamed fluorinated ethylene propylene. By way of example, the dielectric bead 250 is made of solid Teflon. The bead 250 may or may not be part of transformer section 700 .
There is a metal member 300 within the dielectric bead 250 and extending coaxially within the axial bore 240 . The metal member 300 , which is an inner conductor of the connector 100 , has first and second end portions 310 and 320 corresponding to the first and second end portions 210 and 220 of the cylindrical body 200 , and a center portion 330 corresponding to the center portion 230 of the cylindrical body 200 . In the axial bore 240 , the metal member 300 is fixed in place and electrically insulated from the cylindrical body 200 by the dielectric bead 250 . The first end portions 210 and 310 interfit with the first coaxial transmission line 180 .
Specifically, the first end portion 210 of the cylindrical body 200 mates with the outer conductor 186 in metal-to-metal electrical contact through a clamping ferrule 590 , and spring-type contacts of the first end portion 310 of the metal member 300 mates with the center conductor 182 A in metal-to-metal electrical contact. There are numerous standard means in the art to connect cable and connectors in metal-to-metal electrical contact that will not be described in detail.
Further, there is a coupling mechanism 500 to mate the coaxial transmission line 180 to the cylindrical body 200 . It is noted that there are numerous standard means in the art to couple cables and connectors, and they will not be described.
The second end portions 220 and 320 are shaped to interfit or mate with an electrical device. By way of example, the second end portions 220 and 320 comprise a standard 7-16 DIN-type cable interface to interfit with the electrical device. In another configuration, the second end portions 220 and 320 comprise a standard N-type cable interface (not pictured).
The center portions 230 and 330 , and the dielectric bead 250 cooperatively provide for a transformer impedance for matching the first impedance of the first coaxial transmission line 180 and the second impedance of the electrical device. To provide a matching impedance, the connector 100 has a characteristic impedance calculated by EQN. 1 below.
Z char =√{square root over (Z i ·Z o )} EQN. 1
wherein Z char is a characteristic impedance of the transformer section in the connector,
Z i is an impedance of a coaxial transmission line; and Z o is an impedance of an electrical device.
In other words, the maximum power is transferred when the load impedance, i.e., impedance of the electrical device, is the complex conjugate of the source impedance, i.e., impedance of the coaxial transmission line.
For the first embodiment, Z char is the transforming impedance of the connector 100 , Z i is the impedance of the first coaxial transmission line 180 , and Z o is the impedance of the electrical device 900 .
The characteristic impedance of a electrically conducting coaxial body is given by EQN. 2.
Z char = 138 ɛ · log ( D d ) EQN . 2
wherein D is an inside diameter of an outer conductor,
d is an outside diameter of an inner conductor, and ∈ is a dielectric constant of a dielectric between the inner and the outer conductors.
By way of example, the inside diameter of the center portion 330 is D and the outside diameter of the center portion 230 is d. The dielectric constant of air surrounding the center portion 230 is ∈. Applying EQN. 2 to the center portions 230 and 330 , and taking into account an impedance imparted by the dielectric bead 250 , provide the relationships between some of the physical dimensions of the center portions 230 and 330 . For example, a D substantially equivalent to the diameter of the outer conductor 186 of the first coaxial transmission line 180 , results in a center portion 330 of the metal member 300 having a d different than the outside diameter of the center conductor 182 A to provide for a Z char satisfying EQN. 1, when using a 70 ohm coaxial transmission line and a 50 ohm electrical device. Alternatively, the center portions 230 and 330 may have different configurations as long as their respective dimensions satisfy EQNS. 1 and 2.
In other words, center portions 230 and 330 , and the dielectric bead 250 comprise a matching transformer section 700 . As shown in FIG. 1 , the components of the matching transformer section 700 , i.e., center portions 230 and 330 , and the dielectric bead 250 are integral to the connector 100 .
To minimize signal losses in the connector 100 , a transforming length L including the center portions 230 and 330 , and the dielectric bead 250 has a value depending on the frequency of the signal carried in the connector 100 . Electrically, the distance of the transforming length L is from a first impedance transition A between the first impedance and the matching impedance, to a second impedance transition B between the matching impedance and the second impedance. For the embodiment shown in FIG. 1 , the first impedance transition A is at the abutting terminal end of the first coaxial transmission line 180 and the second impedance transition B is at a side of the dielectric bead 250 abutting the second end portions 220 and 320 .
By way of example, a 1920 GHz signal requires a transforming length L of 1.014 inches with solid polyethylene filling the complete cavity of transformer length. In comparison, a connector without the dielectric bead 250 included in the transformer length L of one quarter wavelength in air, requires a length of 1.475 inches for a 1920 GHz signal. In effect, the presence of the dielectric bead 250 allows for a shorter transforming length L and therefore a shorter connector. The final length of bead or percentage of dielectric will be determined by mechanical integrity and cost.
By way of example, a quarter wave transformer can provide a VSWR of approximately 1.02:1 for a signal in the frequency band of 1850 to 1990 MHz. VSWR is the result of reflected waves, and a lower VSWR ratio translates into lower levels of undesirable signal reflections resulting from the connection of transmission lines or devices with mismatched impedance. It is noted that in another configuration (not pictured), the transforming length L can comprise an integral multiple of quarter wavelengths depending on the desired bandwidth.
FIG. 2 illustrates another embodiment of the invention. With respect to the embodiment shown in FIG. 1 , this embodiment differs in the following. Instead of a first end portion 210 of the cylindrical body 200 in electrical contact with the outer conductor 186 (FIG. 1 ), there is a series open circuit outer stub 212 A capacitively coupled to the outer conductor 186 . The capacitive coupling is created by the larger inside diameter of the first end portion 210 of the cylindrical body 200 of the connector 100 surrounding the cable 180 . This cavity is preferably lined with a dielectric lining 214 A to maintain the proper alignment of components between the series open circuit outer stub 212 A and the outer conductor 186 and to prevent electrical contact. The dielectric lining 214 A is made of a suitable dielectric material such as polyethylene.
Additionally, the embodiment includes a resilient gland 510 A disposed at a distal end of the dielectric lining 214 A. Specifically, the coupling mechanism 500 has a hollow inner cavity and a step along the inner surface of the hollow inner cavity in which the resilient gland 510 A is disposed. When the connector 102 is coupled to the cable 180 , i.e., when the coupling mechanism 500 is tightened with respect to the cylindrical body 200 and the cable 180 , the resilient gland 510 A is compressed. As the resilient gland 510 A is compressed, the gland 510 A deforms, and protrudes into a corrugation of the outer conductor 186 . In such an arrangement, the resilient gland 510 A grips the corrugated outer conductor 186 of the coaxial transmission line 180 to hold the same in place and provides a moisture barrier.
Another embodiment of the invention is shown in FIG. 3 . This embodiment differs with respect to the embodiment shown in FIG. 2 in the following. Capacitive coupling is created by an inner diameter of the outer conductor 186 of the coaxial cable 180 that is larger than the outside diameter of an open circuit outer stub 212 B of a connector 103 . Similar to the embodiment described in FIG. 2 , the open circuit outer stub 212 B is preferably covered with a dielectric 214 B to maintain the proper alignment of the components. In this embodiment, the outer body of the cylindrical body 200 is substantially spaced apart from the cable outer conductor and the series open circuit outer stub 212 B to create a quarter wave choke. In this embodiment, the center conductor 182 B of the coaxial transmission line 180 is solid and in electrical contact with a center portion 332 A of a metal member 300 .
This stub design requires a special tool to cut the cavity in the foam 184 . This type of tool is common in CATV cable connector installation. Alternatively, in another embodiment, the series open circuit outer stub 212 B is designed to cut the cavity into the foam 184 to eliminate the need for a special tool.
Additionally, there is a conductive member 520 disposed between the resilient gland 510 B and a distal end of the outer body the connector 103 . The conductive member 520 provides a more effective open circuit outer stub 212 B by creating an electrical contact between the outer conductor 186 of the cable 180 , the outer surface of the cylindrical body 200 , i.e., the outer body of the connector. The resilient gland 510 B in this case is conductive to provide electrical contact to the cable 180 .
FIG. 4 illustrates another embodiment of the invention. This embodiment of the connector 104 differs from the embodiment shown in FIG. 1 in the following regard. Instead of a first end portion 310 of the metal member 300 in electrical contact with the center conductor 182 A (FIG. 1 ), there is a series open circuit inner stub 312 A capacitively coupled to the center conductor 182 A. In this embodiment, the outer diameter of the series open circuit inner stub 312 A is less than the inside diameter of the hollow cavity in the center conductor 182 A. Preferably, there is a dielectric sleeve 314 A of suitable material such as polyethylene to maintain the series open circuit inner stub 312 A in proper alignment with respect to the center conductor 182 A and to prevent electrical contact.
Alternatively, an another embodiment is shown in FIG. 5 . This embodiment is different from the embodiment shown in FIG. 1 with respect to the following. In a connector 105 , there is a series open circuit inner stub 332 B at the center portion 330 of the metal member 300 . The series open circuit inner stub 332 B has a hollow cavity in which a projecting solid end portion of an inner conductor 182 B of the coaxial transmission line 180 is disposed. The inside diameter of the hollow cavity is greater than the outer diameter of the solid inner conductor 182 B. A dielectric lining 324 is preferably disposed on the inside surface of the hollow cavity to maintain proper alignment of the components and to prevent electrical contact. This design is applicable to smaller cables that are made with solid center conductors.
FIG. 6 illustrates yet another embodiment of the invention. With respect to the embodiment shown in FIG. 2 , this embodiment differs in the following respect. This embodiment combines the inner capacitive coupling configuration shown in FIG. 4 with the outer capacitive coupling configuration shown in FIG. 2 . In the connector 106 , the impedance property of each of the two stubs 212 C, 312 C will normally need to be modified when the two stubs are combined to maintain the correct impedance to conjugate the reactance of the transformer section 700 over the desired bandwidth.
To impede the flow of radiation and current toward the outside of the outer stub, a yet another embodiment of the invention is shown in FIG. 7 . This embodiment differs from the embodiment described in FIG. 6 with respect to the following. Radially around the series open circuit outer stub 212 D, there is an outer choke 600 , i.e., a short circuit stub. Preferably, the choke 600 is a dielectric layer such as an air gap, preferably, or a dielectric sleeve, that is disposed within first end portion 210 of the cylindrical body 100 of the connector 107 . With an air gap, the choke 600 is physically longer than quarter wavelength dielectric loaded stub. Further, the embodiment includes the conductive member 520 and conductive gland 510 B. The conductivity of the gland 510 B need not be high since the gland 510 B is disposed at a high-impedance position where low current exists. In an alternative embodiment, the resilient gland 510 B may replace the conductive member 520 depending on the conductivity of the resilient gland 510 B.
In all the embodiments shown in FIGS. 2-7 , the length of the series open stub inner conductors and the series open stub outer conductors is electrically one quarter wave long. By way of example, if the dielectric lining 214 C and the dielectric sleeve 314 C shown in FIG. 4 are made of polyethylene, the quarter wave in polyethylene is 1.014 inches long for a 1920 MHz signal. In such a configuration, the inner stub can provide less than 10 ohm impedance and the outer stub will be approximately 25 ohms impedance with a corrugated outer conductor. The exact physical length of the stub is usually determined by test since the volume of cavity created by conductors and connector is a combination of dielectric and air to maintain the slip fit requirement for field installation of connector.
The cable of the present invention has low losses given the state of the art of the materials for cables such as foam polyethylene with densities below 0.18 g/cm utilized to effect the invention. The use of at least one series open circuit stub conductor as in FIGS. 2-7 provides improved bandwidth characteristic over a connector using only a simple quarter wavelength transformer (FIG. 1 ). For example, the series open stubs and the integral transformer as shown in FIG. 6 of the present invention allows for a greater bandwidth covering the worldwide PCS band of 1700 to 2300 MHz with a VSWR of less than 1.02:1. On the other hand, a connector without the series open stubs, i.e., embodiment shown in FIG. 1 , covers a frequency band of 1850 to 1990 MHz with a VSWR of about 1.02:1.
Physically, the incorporation of the series open stub conductor allows for simplified connector installation by allowing for less precise cutting of the coaxial transmission cable and less critical torque requirements to install the connector. The utilization of a non-metallic connector contact through the use of a dielectric sleeve allows the connector to be hand tightened. Furthermore, capacitively coupling both inner and outer conductors eliminates all passive intermodulation (PIM) from the most likely source while eliminating the most expensive and complicated parts of the connector.
In use, the connector only needs to be hand tightened to properly connect the coaxial transmission line to the connector because the use of open circuit stubs reduce the need for precise electrical metal to metal contact between the coaxial transmission line and the connector.
The invention is described in terms of the above embodiments which are to be construed as illustrative rather than limiting, and this invention is accordingly to be broadly construed. The principle upon which this invention is based can also be applied to other frequency bands of interest.
It is contemplated that numerous modifications may be made to the present invention without departing from the spirit and scope of the invention as defined in the following claims. | A frequency selective low loss transmission system for communicating a signal using a coaxial cable of one impedance to a device of different impedance. A connector with a matching transformer is integral to the connector which terminates with a standard interface. The invention also includes a coupling mechanism to couple the coaxial cable with the connector. The invention can also include series open stub conductors for capacitive coupling to the conductors of the coaxial cable. In addition to low losses over a broad frequency range, the connector facilitates connector installation due to the series open stub conductor while reducing cost and complexity of both coaxial cable and connector. | 7 |
BACKGROUND
The present exemplary embodiment relates generally to processing an electronic document file for printing on a select printer. It finds particular application when the electronic document file includes print parameter information associated with a former printer that are at least not fully compatible with a new printer. However, it is to be appreciated that the exemplary embodiments described herein are also amenable to printing any electronic document file that includes print parameter information associated with a different printer than the printer selected for printing.
Traditionally, vendors have a hard time entering into environments where competitors have an established presence. Customers tend to resist changing what already works for them for a variety of reasons. When a customer does change to a different vendor's devices, the new vendor works with the customer in order to provide a smooth transition.
One issue that arises during this transition period is that the customer may find that their documents, which used to print correctly on previous vendor's devices, do not print correctly on the new vendor's devices. The root causes tend to be differences in media sizes, media types, and input tray selection, or differences between vendor-specific features.
Device vendors tend to release printer drivers that allow consistency amongst their own devices and do little to no work to ensure any compatibility between devices from other vendors. In fact, it's often advantageous to promote maximum incompatibility between devices from other vendors in order to make customers reluctant to switch vendors.
The customers do not care what the root causes are, their only concern is that when they printed on the previous vendor's devices, what used to print correctly now does not, forcing them to re-print documents and waste valuable resources. One way to resolve this issue is to limit replacement of current vendor devices to devices from other vendors that are more compatible. With this approach, the customer has to trade off new functionality with compatibility. Another way to resolve the issue is to revise all the customer documents to be compatible with the new vendor's devices. The customer is likely to lose revenue after deciding to switch to another vendor's device even if some of the incompatibility issues are resolved because of the amount of work required in modifying documents. Under these circumstances, the customer may remain with the current vendor and the potential new vendor loses revenue from losing the potential new customer.
INCORPORATION BY REFERENCE
None.
BRIEF DESCRIPTION
In one aspect, a method for processing an electronic document file for printing in provided. In one embodiment, the method includes: a) receiving an electronic document file for printing on a select printer at a print driver for the select printer; b) determining the electronic document file includes at least some different print parameter information associated with a different printer based at least in part on configuration data, wherein the configuration data includes mapping information between different print parameter information associated with the different printer and select printer information associated with the select printer, wherein the different print parameter information and the at least some different print parameter information are at least not fully compatible with the select printer; c) identifying and transforming the at least some different print parameter information to corresponding select print parameter information based at least in part on the mapping information; d) processing document print parameter information associated with the electronic document file received in a), wherein at least a portion of the document print parameter information was transformed from the at least some different print parameter information identified in c); and e) sending a print stream from the print driver to the select printer for printing the electronic document file in a manner consistent with the at least some different print parameter information.
In another aspect, an apparatus for processing an electronic document file for printing is provided. In one embodiment, the apparatus includes: a storage device storing a print driver associated with a select printer and a configuration file accessible to the print driver, wherein the configuration data includes mapping information between different print parameter information associated with a different printer and select print parameter information associated with the select printer, wherein the different print parameter information is at least not fully compatible with the select printer; and a processor in operative communication with the storage device to selectively use the print driver in conjunction with printing an electronic document file on the select printer. In this embodiment, the print driver includes: an input module that receives the electronic document file for printing on the select printer; a filter module in operative communication with the input module and the storage device to access the configuration data, wherein the filter module uses the configuration data to determine the electronic document file includes at least some different print parameter information, wherein the at least some different print parameter information is at least not fully compatible with the select printer; a mapping module in operative communication with the filter module and the storage device to use the configuration data to identify and transform the at least some different print parameter information to corresponding select print parameter information based at least in part on the mapping information; a processing module in operative communication with the filter module and the mapping module to process document print parameter information associated with the electronic document file, wherein at least a portion of the document print parameter information was transformed from the at least some different print parameter information; and an output module that sends a print stream to the select printer for printing the electronic document file in a manner consistent with the at least some different print parameter information.
In yet another aspect, another method for processing an electronic document file for printing is provided. In one embodiment, the method includes: a) generating mapping information between different print parameter information associated with a different printer and select print parameter information associated with a select printer and storing the mapping information in configuration data, wherein the different print parameter information is at least not fully compatible with the select printer; b) receiving an electronic document file for printing on the select printer at a print driver for the select printer; c) determining the electronic document file includes at least some different print parameter information based at least in part on the configuration data, wherein the at least some different print parameter information is at least not fully compatible with the select printer; d) identifying and transforming the at least some different print parameter information to corresponding select print parameter information based at least in part on the mapping information; e) processing document print parameter information associated with the electronic document file received in b), wherein at least a portion of the document print parameter information was transformed from the at least some different print parameter information identified in d); and f) sending a print stream from the print driver to the select printer for printing the electronic document file in a manner consistent with the at least some different print parameter information.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a screen view of an exemplary dialog box associated with an exemplary embodiment of a mapping tool for mapping print parameter information between different printers;
FIG. 2 is a screen view of another exemplary dialog box associated with an exemplary embodiment of a mapping tool for mapping print parameter information between different printers;
FIG. 3 is a screen view of yet another exemplary dialog box associated with an exemplary embodiment of a mapping tool for mapping print parameter information between different printers;
FIG. 4 is a screen view of still another exemplary dialog box associated with an exemplary embodiment of a mapping tool for mapping print parameter information between different printers;
FIG. 5 is a screen view of still yet another exemplary dialog box associated with an exemplary embodiment of a mapping tool for mapping print parameter information between different printers;
FIG. 6 is a screen view of an exemplary dialog box associated with a software application program showing selection of a paper source in conjunction with an exemplary embodiment of a print driver supporting options provided by a select printer;
FIG. 7 is a screen view of an exemplary dialog box associated with a software application program showing selection of a paper source in conjunction with an exemplary embodiment of a print driver supporting options provided by both a select printer and a different printer;
FIG. 8 is a flowchart showing an exemplary embodiment of a process for processing an electronic document file for printing;
FIG. 9 is a block diagram of an exemplary embodiment of a system for processing an electronic document file for printing;
FIG. 10 is a block diagram of another exemplary embodiment of a system for processing an electronic document file for printing that includes an exemplary mapping tool for generating mapping information for use in conjunction with the printing; and
FIG. 11 is a flowchart showing another exemplary embodiment of a process for processing an electronic document file for printing.
DETAILED DESCRIPTION
This disclosure describes various embodiments of methods and systems in which a select print driver can be dynamically configured to allow customers to map information for media sizes, type, media input trays, or any variety of features not specifically supported by a corresponding select printer or family of select printers with which the select print driver is used. Print driver pre-configuration files may be generated before the select print driver is installed and loaded when the select print driver is installed or invoked. The select print driver may automatically make internal adjustments to utilize the information from different print drivers and present options supported by different printers with which the different print drivers are used as if such options were supported by the select printer.
A mapping tool associated with the select printer could be used to allow a user (e.g., Systems Administrator, customer, or sales representative) to examine a different print driver and collect different print parameter information to allow the select print driver to mimic features associated with the different printer. The different print parameter information may include, but not be limited to, display strings used by the different print driver and any required IDs used to correctly select the different specified attributes in the application. Features, such as media size, may also require media dimensions.
The mapping tool may also provide a user interface showing such things as input trays for the different printer and available input trays for the select. For example, the mapping tool may allow users to select a tray for the different printer and a corresponding tray for the select printer to be utilized when the tray for the different printer is selected. The screen shots in FIGS. 1-5 show exemplary dialog boxes associated with an exemplary embodiment of a mapping tool. Once the user is satisfied with the mapping of the different print driver features to the select print driver features, the mappings information may be saved to a configuration file or operating system specific features, such as a Registry, for use by the select print driver.
In order to fully utilize the select print driver, the mapping tool may be used in conjunction with an existing environment with the different printer that is being replaced by the select printer. Additionally, some mechanism may be used to provide the configuration data with the different printer-to-select printer mappings. This mechanism could be as simple as a Windows registry file that is added to a client PC being used for printing. A more complex mechanism could use a server in the “cloud” (e.g., communication network accessible to the client PC via any suitable network and/or gateway) that enables delivery of a preconfigured configuration file along with the select print driver without breaking digital signatures to push the mapping information to the client PC used for printing via an automated process.
Once the configuration data with appropriate mapping information has been made available to the select print driver, the select print driver may automatically configure itself each time it is loaded by the operating system to mimic the different print driver. No additional interaction by the user is required at print time except that which is normally required to print documents.
From a customer's perspective, they can get the improved performance expected from the select print driver without having to determine if any changes to existing documents are required in order for them to be compatible with the select printer. Even though the select printer may provide only select printer options, the UI for the select print driver may present options for both the select printer and the different printer. If possible, the select printer options may be presented first. Some software program applications sort the string for certain print parameter information presented in the print driver UI alphabetically. For these applications, the options for the select printer and the different printer may be intermixed in the display order. The information may be displayed in any suitable manner.
FIG. 6 shows a screen view of an exemplary dialog box associated with Microsoft Word for selection of a paper source in conjunction with an exemplary embodiment of a select print driver supporting options provided only by a select printer. Alternatively, FIG. 7 shows a screen view of an exemplary dialog box associated with Microsoft Word for selection of a paper source in conjunction with an exemplary embodiment of a select print driver supporting options provided by both a select printer and a different printer.
Internally, within the select print driver, constraints and restrictions imposed on the various printing features still apply. As far as the select print driver is concerned, the user is simply utilizing select printer—regardless of whether the user is using the select print driver in conjunction with a software application program to select a feature support by the different printer to print on the select printer. In other words, no special actions are required by the user and printing is accomplished in the same manner with which they were accustomed when using the different printer.
Gradually, customers are expected to migrate to the capabilities of the select printer as they create and/or modify their documents. For example, if possible, each time a document is saved it may be automatically updated to utilize features of the select printer. However, if the customer does not modify a particular document, no further action will be required because the document will continue to print in the same manner as it did before a transition from the different printer to the select printer.
This ability to “mimic” a different print driver may give the vendor for the select printer a distinct advantage over its competitors. For example, this may allow the vendor for the select printer to move into customer sites that have previously been resistant to switch to a new printer. Additionally, the select print driver can be extended to include a variety of other features supported by many different printers. Support costs may go down for the customer because they will not have to be assisted in learning how to map existing document features to features of the select printer. The select print driver could also be used to transition from older versions of printers to an updated version of the printer from the same vendor.
Additionally, customers that decide to switch from the select printer to an environment with a new printer from a previous vendor or yet another vendor may be faced with exactly the same issue and may again use an embodiment of the process described herein to transition again without having to change existing documents that had been setup to print on any previous printers.
In summary, an electronic document file created by a software application (e.g., Microsoft Word) can have printer-specific information for a former printer or family of printers embedded within it. The printer-specific information may include paper sizes, paper trays, and paper types that the former printer or family of printers support. However, the printer-specific information embedded in the electronic document file may not be supported by other printers or families of printers. The various embodiments of methods and apparatus disclosed herein enable a new print driver for a new printer or family of printers can be configured such that the new printer or family of printers can cleanly print an electronic document file with embedded printer-specific information that is compatible with a former printer or family of printers and at least not fully compatible with the new printer or family of printers. In short, this makes the new print driver compatible with the former print driver so that electronic document files created with embedded printer-specific information for the former printer or family of printers can be printed on the new printer or family of printers without having to edit or alter the embedded printer-specific information. This enables printing of documents on the new printer or family of printers that were previously intended to be printed on the former printer or family of printers.
In one embodiment, a user would use a printer information mapping tool to specify how embedded printer-specific information (e.g., paper sizes, paper trays, paper types, etc.) for the former printer or family of printer maps to corresponding printer information for the new printer or family of printers. When the mappings are completed, the mapping tool produces configuration data containing the mappings. The new print driver imports the mapping information associated with the configuration data. The new print driver uses this mapping information to present a combined list that includes printer information for both the new printer and the former printer. When printing a document containing printer information associated with the former printer, the new print driver uses the mapping information to transform the printer information associated with the former printer into corresponding printer information associated with the new printer so that when the electronic document file prints on the new printer the document produced is consistent with documents that would be produced by the former printer.
For example, this facilitates transition of a user's printer or family of printers to another printer or family of printers by providing a means for existing electronic document files to satisfactorily print on the new printer or family of printers. This is especially useful for streamlining installation of a new printer or family of printers with minimal disruption to users.
With reference to FIG. 8 , an exemplary embodiment of a process 800 for processing an electronic document file for printing begins at 802 where an electronic document file may be received for printing on a select printer at a print driver for the select printer. Next, the process may determine the electronic document file includes at least some different print parameter information associated with a different printer based at least in part on configuration data ( 804 ). The configuration data may include mapping information between different print parameter information associated with the different printer and select printer information associated with the select printer. The different print parameter information and the at least some different print parameter information may be at least not fully compatible with the select printer.
At 806 , the at least some different print parameter information may be identified and transformed to corresponding select print parameter information based at least in part on the mapping information. Next, document print parameter information associated with the electronic document file received in 802 may be processed ( 808 ). At least a portion of the document print parameter information may have been transformed from the at least some different print parameter information identified in 806 . At 810 , a print stream may be sent from the print driver to the select printer for printing the electronic document file in a manner consistent with the at least some different print parameter information.
In another embodiment, the process 800 may also include generating the mapping information used in 804 and 806 using a mapping tool. The mapping information may be based at least in part on comparing the different print parameter information to the select print parameter information. In a further embodiment, the comparing and generating may be performed automatically in response to the mapping tool being initiated by a user. Alternatively, in another further embodiment, the comparing and mapping may be performed interactively via a user interface in response to the mapping tool being initiated by a user and the generating of the mapping information may be performed automatically in response to a user activation via the user interface indicating the comparing and mapping is complete. In yet another further embodiment, the comparing and generating may be performed automatically in conjunction with installation of the print driver.
In yet another embodiment of the process 800 , the select printer and the print driver are co-located in a computer system. In a further embodiment, the computer system is a server system. Alternatively, in another further embodiment, the computer system is a stand-alone computer workstation. In still another embodiment of the process 800 , the select printer is a network device associated with a computer network and the print driver is located within a networked computer workstation in operative communication with the select printer via the computer network.
With reference to FIG. 9 , an exemplary embodiment of a system 900 for processing an electronic document file 902 to form a print stream 904 for printing on a select printer 906 may include a storage device 908 and a processor 910 . The storage device 908 may store a print driver 912 associated with the select printer 906 and configuration data 914 accessible to the print driver 912 . The configuration data 914 will include mapping information 916 between different print parameter information associated with a different printer and select print parameter information associated with the select printer 906 . The different print parameter information may be at least not fully compatible with the select printer 906 . The processor 910 may be in operative communication with the storage device 908 to selectively use the print driver 912 in conjunction with printing the electronic document file 902 on the select printer 906 .
In this embodiment, the print driver 912 may include an input module 918 , a filter module 920 , a mapping module 922 , a processing module 924 , and an output module 926 . The input module 918 may receive the electronic document file 902 for printing on the select printer 906 . The filter module 920 may be in operative communication with the input module 918 and the storage device 908 to access the configuration data 914 . The filter module 920 may use the configuration data 914 to determine the electronic document file 902 includes at least some different print parameter information. The at least some different print parameter information may be at least not fully compatible with the select printer 906 . The mapping module 922 may be operative communication with the filter module 920 and the storage device 908 to use the configuration data 914 to identify and transform the at least some different print parameter information to corresponding select print parameter information based at least in part on the mapping information 916 . The processing module 924 may be operative communication with the filter module 920 and the mapping module 922 to process document print parameter information associated with the electronic document file 902 . At least a portion of the document print parameter information may be transformed from the at least some different print parameter information. The output module 926 may send the print stream 904 to the select printer 906 for printing the electronic document file 902 in a manner consistent with the at least some different print parameter information.
With reference to FIG. 10 , another exemplary embodiment of a system 1000 for processing an electronic document file may include a mapping tool 1028 in operative communication with the storage device 1008 to generate mapping information 1016 based at least in part on comparing different print parameter information 1030 to select print parameter information 1032 . The mapping information 1016 may be stored on the storage device 1008 in the configuration data 1016 . In a further embodiment, the mapping tool 1028 may automatically compare the different print parameter information 1030 to the select print parameter information 1032 to generate the mapping information 1016 in response to being initiated by a user. Alternatively, in another further embodiment, the mapping tool 1028 may include a user interface module 1034 to enable the user to interactively compare and map the different print parameter information 1030 to the select print parameter information 1032 . In this embodiment, the mapping tool 1028 may generate the mapping information 1016 in response to a user activation via the user interface 1034 indicating the comparing and mapping is complete. In still another further embodiment, the print driver 1012 may include the mapping tool 1028 . In this embodiment, the mapping tool 1028 may be initiated automatically to compare the different print parameter information 1030 to the select print parameter information 1032 to generate the mapping information 1016 in conjunction with installation of the print driver 1012 on the storage device 1008 .
With reference again to FIG. 9 , in another embodiment of the system 900 , the storage device 908 and processor 910 may be co-located in a computer system. In a further embodiment, the computer system may be a server system. Alternatively, in another further embodiment, the computer system may be a networked computer workstation. In still another further alternate embodiment, the computer system may be a stand-alone computer workstation.
With reference to FIG. 11 , an exemplary embodiment of a process 1100 for processing an electronic document file for printing begins at 1102 where mapping information between different print parameter information associated with a different printer and select print parameter information associated with a select printer may be generated and stored in a configuration file or operating system specific feature, such as a Registry. The different print parameter information may be at least not fully compatible with the select printer. Next, an electronic document file may be received for printing on the select printer at a print driver for the select printer ( 1104 ). At 1106 , the process may determine the electronic document file includes at least some different print parameter information based at least in part on the configuration data. The at least some different print parameter information may be at least not fully compatible with the select printer. Next, the at least some different print parameter information may be identified and transformed to corresponding select print parameter information based at least in part on the mapping information ( 1108 ). At 1110 , document print parameter information associated with the electronic document file received in 1104 may be processed. At least a portion of the document print parameter information may be transformed from the at least some different print parameter information identified in 1108 . Next, a print stream may be sent from the print driver to the select printer for printing the electronic document file in a manner consistent with the at least some different print parameter information ( 1112 )
It will be appreciated that several of the above-disclosed and other features and functions, or alternatives thereof, may be desirably combined into many other different systems or applications. Also that various presently unforeseen or unanticipated alternatives, modifications, variations or improvements therein may be subsequently made by those skilled in the art which are also intended to be encompassed by the following claims. | A method for processing an electronic document file for printing may include receiving an electronic document file at a print driver for a select printer; determining the electronic document file includes different print parameter information for a different printer based on configuration data; identifying and transforming the different print parameter information to select print parameter information based on mapping information; processing document print parameter information associated with the electronic document file, where a portion of the document print parameter information was transformed from the different print parameter information; and sending a print stream to the select printer for printing the electronic document file consistent with the different print parameter information. A related system may include a storage device and a processor. The storage device may include the print driver and configuration data with the mapping information. The print driver may include input; filter; mapping; processing; and output modules. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part application of my copending application, Ser. No. 126,997, filed Mar. 3, 1980 now abandoned, said application being a continuation-in-part application of my copending application, Ser. No. 857,526, filed Dec. 5, 1977, now U.S. Patent No. 4,167,945, said application being a continuation-in-part of my copending application Ser. No. 764,229, filed Jan. 31, 1977, now U.S. Pat. No. 4,061,731, said application being a continuation-in-part application of my copending application Ser. No. 576,858, filed June 4, 1975, now U.S. Pat. No. 4,006,220.
BACKGROUND OF THE INVENTION
Epsilon-aminocaproic acid and structurally related compounds have long been recognized for their antifibrinolytic properties and for treatment of acute bleeding syndromes. These compounds are administered either intravenously or orally. There is no mention of topical administration of these compounds in the clinical literature.
In addition to its use as an inhibitor of fibrinolysis, epsilon-aminocaproic acid has been previously reported as exhibiting anti-inflammatory properties, when administered orally. See Reiss, "The Therapeutic Effect of Epsilon-Aminocaproic Acid with Special Reference to Atopic Dermatitis," British Journal of Dermatology, Vol. 85, Page 76 (1971). According to Reiss et al, "The Therapeutic Effect of ε-Aminocaproic Acid on Anetoderma Jadassohn," Dermatologica, Vol. 146, pp. 357-60 (1973), epsilon-aminocaproic acid can be administered orally for the treatment of anetoderma of Jadassohn.
OBJECTS OF THE PRESENT INVENTION
It is a primary object of the present invention to provide a new and efficient method for the drying and diminution of cutaneous and mucosal lesions including, for example, papulonodular, vesiculobullous and erosive-type lesions.
It is a further object of the present invention to provide a method for the relief of the sensations of burning, pain and/or itching of cutaneous and mucosal surfaces which may or may not accompany the aforementioned lesions.
BRIEF SUMMARY OF THE INVENTION
Briefly, the present invention relates to the drying and diminution of cutaneous and mucosal lesions which comprise the step of topically applying to the situs of the lesion(s), a composition consisting essentially of: (A) a compound selected from the group consisting of: (1) aminocaproic acid, (2) a compound of the formula 4NH 2 CH 2 (CH 2 ) 4 COOH.CaX 2 wherein X is chloride or bromide, or (3)mixtures thereof, and (B) a pharmaceutically acceptable carrier.
The present invention also relates to the relief of the sensations of burning, pain and/or itching of cutaneous and mucosal surfaces which comprises the step of applying the composition to the situs of the condition wherein the active compound is applied in an amount effective to relieve the condition being treated.
DETAILED DESCRIPTION OF THE INVENTION
The term aminocaproic acid, as used in this specification, is intended to include the various forms of aminocaproic acid as well as epsilon-aminocaproic acid which is particularly preferred for the process of the present invention.
According to one embodiment of the present invention, the process of this invention is effectively used for drying and diminution of one or more cutaneous or mucosal surface lesions, which may be of the papulonodular, vesiculobullous or erosive-type, provided that an effective amount of the pharmacologically active ingredient is applied to the lesions in an amount sufficient to cause the drying and diminution of the lesions. By effective amount, it is intended that between about 0.025 and 0.075 grams of said pharmacologically active ingredient be applied to a surface area generally between about 3 mm 2 and 6.45 cm 2 . Thus, from 0.1 to 0.6 ml, and preferably 0.2 ml of a composition comprising between about 0.25 and 0.75 grams of the pharmacologically active compound, the balance being the inert, pharmaceutically acceptable carrier, is applied to a surface area of between about 3 mm 2 and 6.45 cm 2 to effectively control the aforementioned condition with proportionally greater amounts being employed for larger or smaller surface areas.
It is understood that the lesions being treated in accordance with this invention are usually present without associated edema. Edema generally refers to the accumulation of tissue fluids which may arise from several causes, e.g., congestive heart failure, nephritis, varicose veins, cirrhosis, and allergic phenomena. Edema is generally a condition existing beneath a cutaneous or mucosal surface, whereas the lesions being treated in accordance with this invention generally exist on said cutaneous or mucosal surfaces.
In addition, the effective amounts of the active ingredient as well as the amount of the composition used for the relief of the sensation of burning, pain and/or itching which may or may not accompany papulonodular, vesiculo-bullous or erosive-type lesions (erosions, minor lacerations, abrasions, fissures and ulcerations) is an amount effective to diminish said burning, pain and/or itching of the cutaneous or mucosal surface at the situs of such condition. This process may also be used for the relief of the sensation of burning, pain and/or itching not associated with the aforementioned cutaneous or mucosal lesions, but due to heat burn, sunburn, water burn, chemical burn, and contact dermatitis.
It is also noted that erythema of cutaneous and/or mucosal surfaces may, or may not be present when an individual experiences the sensation of burning, pain and/or itching of said surfaces. If erythema is present with the burning, pain and/or itching sensations, the process of this invention tends to diminish the erythema while relieving the burning, pain and/or itching sensation. The amount of the composition used is generally between 0.1 and 0.6 ml of the composition for a surface area between about 3 mm 2 and 6.45 cm 2 with proportionally greater amounts being employed for larger or smaller surface areas.
The term "diminution," as used in this specification, refers to the reduction in size and/or flattening of a lesion, or reduction in degree of sensation, being treated in accordance with this invention.
Carrier materials suitable for use in the instant process include those well-known for use in the medical art as bases for ointments, solutions, lotions, powders, salves, creams, aerosols, gels, and the like. Suitable carriers include, for example, water, liquid alcohols, liquid glycols, liquid polyalkylene glycols, liquid esters, liquid amides, liquid protein hydrolysates, liquid alkylated protein hydrolysates, liquid lanolin and lanolin derivatives, and like materials commonly employed in medicinal compositions. Exemplary carriers herein include alcohols, including both monohydric and polyhydric alcohols, e.g., ethanol, isopropanol, glycerol, sorbitol, 2-methoxyethanol, diethyleneglycol, ethylene glycol, hexyleneglycol, mannitol, and propylene glycol; ethers such as diethyl or dipropyl ether; polyethylene glycols and methoxypolyoxyethylenes (carbowaxes having molecular weight ranging from 200 to 20,000); polyoxyethylene glycerols, polyoxyethylene sorbitols, and stearoyl diacetin. Oil-in-water emulsions such as cold cream bases can also be used.
Preferably, the carrier herein is the pharmaceutically acceptable liquid alcohol containing from about 2 to about 6 carbon atoms. Mixtures comprising from about 0% to 80% by weight of water and about 20% to 100% by weight of said C 2 to C 6 alcohols are also suitable. Suitable alcohols herein include ethanol, isopropanol, hexanol, and the like. Especially preferred carriers herein are water-ethanol (ethyl alcohol) mixtures at a weight ratio of about 1:20 to 5:1. Ethanol containing from about 5% to about 50% by weight of water, especially 40:60 volume (i.e., 33.35% by weight) ethanol-water, is preferred as the carrier.
The compositions herein can also include various agents and ingredients commonly employed in dermatological ointments and lotions. For example, thickening agents, such as carboxymethylcellulose, coloring agents and the like can be present in the compositions to provide a more pleasing aesthetic aspect.
The term "pharmaceutically acceptable carrier," as used herein, is meant to include any liquid, gel, solvent, liquid diluent, fluid ointment base, fluid suppository base and the like, which is suitable for use in contact with living animal tissue without any untoward physiological response and which does not interact with the other components of the compositions in a deleterious manner and which can be used to establish the compositions herein in their preferred liquid form.
It is understood that the process of the present invention also relates to the diminution of erythema sometimes accompanying papulonodular, vesiculobullous, or erosive-type lesions when the active ingredient is used in an amount effective to cause the drying and diminution of these lesions. It is also understood that the treatable erythema need not be associated with the lesions being treated in accordance with this invention.
It is understood that the processes of this invention are to be used for the treatment of the discussed conditions in both animals and humans.
EXAMPLE
A composition of the following ingredients is useful for the relief of burning, itching and pain associated with a small cutaneous laceration (about 5 cm long and 1 mm wide):
______________________________________Epsilon-aminocaproic acid 5 gmsWater 20 ml (approximate)Hydrochloric acid To adjust pH to about 6.8Preservative (benzoyl alcohol) 0.9% by weight of total composition______________________________________
One drop (about 0.2 ml) of the composition was found to decrease pain and burning and decrease erythema of the inflammation associated therewith.
The term "topically applying" as used herein includes the application of the pharmacologically active ingredient to the surface being treated and the impregnation of the surface with the active ingredient. | A method for the drying and diminution of cutaneous and mucosal lesions and the relief of the sensations of burning, pain and itching of cutaneous and mucosal surfaces is discussed. The process comprises the step of topically applying to the situs of the condition being treated, a composition consisting essentially of (A) a compound selected from the group consisting of: (1) aminocaproic acid, (2) a compound of the formula 4NH 2 CH 2 (CH 2 ) 4 COOH.CaX 2 wherein X is chloride or bromide, or (3) mixtures thereof, and (B) an inert, pharmaceutically acceptable carrier. | 8 |
CROSS-REFERENCE TO RELATED APPLICATION
The present invention is an improvement over the invention disclosed and claimed in my prior U.S. Pat. No. 5,941,321, issued Aug. 24, 1999 on a “METHOD AND APPARATUS FOR SHORT RADIUS DRILLING OF CURVED BOREHOLES.”
FIELD OF THE INVENTION
This invention is related to a method and apparatus for boring a hole in the earth, or in material having similar characteristics. More particularly, this invention relates to an apparatus for boring a hole having at least one non-linear segment.
BACKGROUND OF THE INVENTION
Horizontal drilling technology has come a long way in the past 20 years, and is now an accepted drilling method that has numerous benefits for the recovery of hydrocarbons. Horizontal drilling can be used as both an exploration tool and as a completion technique. The benefits of horizontal drilling when used as part of a completion method include increased drainage area, connecting fracture permeability to the well bore, and reducing drawdown pressures. There also is a strong desire in the industry to reduce the surface foot print caused by drilling activities, and horizontal drilling has proven to be an effective means of reducing the number of wells required to develop a field.
Horizontal drilling is critical for exploiting reservoirs that have little to no primary permeability. To achieve maximum productivity, a horizontal well can be oriented in a particular direction to maximize the number of fractures that the well intersects. By connecting fractures to a well bore, horizontal drilling has been able to turn economically unproductive reservoirs into economic successes. Vertical wells have a much lower probability than horizontal wells of repeatedly intersecting fractures, because nearly all fractures are vertically oriented. A properly placed horizontal well also has been shown to dramatically lower the drawdown pressure across the face of the well bore, and, thus, horizontal drilling also can be applied to water drive reservoirs to eliminate coning.
Generally, a horizontal well comprises at least three distinct segments. First, a vertical borehole extends from the surface to a desired depth beneath the surface, at which point a second, non-linear (i.e. “curved”) borehole transitions the vertical borehole to a third borehole segment (i.e. the “horizontal” segment). The orientation of the third borehole segment, though, depends upon the curvature of the second segment. Thus, the third segment is not necessarily horizontal. In principle, the curvature of the second segment can be adjusted to drill a hole to any desired subsurface location or strata. In practice, though, steering a drill bit with sufficient precision to create the desired curvature has proven difficult.
Typical motor-driven, bottom-hole assemblies have a bent housing that tilts the axis of the drill bit to drill a curved borehole. The orientation of the obtuse angle created by the fixed bend is known as “tool face.” The rigid bend in the drill string points the face of the drill bit in a direction that is tangential to the longitudinal axis of the drill string. But because the bent housing is a fixed part of the drill string, a curved hole can be drilled with these conventional devices only when the drill string is not rotating. Consequently, the technique that uses this type of device is commonly referred to as “slide drilling.”
U.S. Pat. No. 5,941,321 (issued Aug. 24, 1999) describes a “rotary steerable” drilling tool that overcomes some of the disadvantages associated with the conventional slide drilling tools, and permits significantly faster penetration rates because of better hole cleaning. The rotary steerable tool is an apparatus for drilling curved boreholes, particularly in applications that require short radius curvatures, commonly referred to in the art as an “aggressive build rate.” The rotary steerable tool of the '321 patent includes a sliding tube mounted for sliding movement within the central bore of the drill pipe sub-assembly. The upper end of the sliding tube is provided with a tapered throat that makes the sliding tube responsive to pressure from fluid flowing through the drill string. Fluid pressure pushes a deflection device against the side of the borehole, urging the lower end of the drill string to be tilted away from the longitudinal axis of the borehole above the drill bit such that the drill bit will tend to drill in a direction away from the longitudinal axis of the borehole. A knuckle joint also can be included in the drill string between the rotary steerable tool and the drill bit, which can decrease the radius of curvature of a non-linear borehole.
While the rotary steerable tool disclosed in the '321 patent overcomes many disadvantages of the conventional slide drilling procedures, there still remains room for improvement. In particular, the tapered throat on the upper end of the sliding tube restricts the flow of drilling fluid as it passes through the drill string. Such a fluid restriction can increase the pressure above the tool and adversely affect the bit hydraulics, requiring more powerful and more expensive fluid pumps to compensate for the restriction. Additionally, the rotation of the drill pipe tends to cause the eccentric sleeve of the tool to rotate within the borehole, which can cause the deflection device to collapse or steer the drill bit in an undesired direction.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a rotary steerable tool that improves the flow characteristics of drilling fluid within the tool, and improves the isolation of the tool from the rotational forces of the drill string.
The invention described in detail below is an improved rotary steerable tool for steering an earth-penetrating drill bit. The improved rotary steerable tool comprises an eccentric sleeve having a cylindrical bore and a piston chamber; a piston spring positioned within the piston chamber so that one end of the piston spring engages the piston chamber; a piston that engages the piston spring; a deflection pad mounted to the piston through a port in the piston chamber; a mandrel positioned in the eccentric sleeve, the mandrel having a slot that exposes a bore in the mandrel to the mandrel's external surface; a control spring positioned in the mandrel; and a control tube positioned in the coiled control spring and the mandrel so that the control spring engages the tube and exerts a force on the control tube that urges the control tube vertically downward. In response to increasing pressure of drilling fluid in the mandrel, the control tube moves upward against the force of the control spring and exposes the piston to the drilling fluid through the slot in the mandrel. In turn, the piston responds to the pressure of the drilling fluid and causes the deflection pad to move outward and engage the borehole wall. Internal bearings isolate the eccentric sleeve and the deflection pad from the mandrel, thus allowing the mandrel to rotate freely without exerting any rotational force on the eccentric sleeve. External bearing assemblies strategically placed above and below the eccentric sleeve further isolate the mandrel and the eccentric sleeve from the borehole surfaces.
Additionally, a guide lug fixed to the control tube engages the slot in the mandrel and an alignment sleeve mounted to the eccentric sleeve. In response to increasing pressure of drilling fluid in the mandrel, the guide lug, so fixed to the control tube, moves upwardly in the slot to a position above the tip of the alignment sleeve, so that the mandrel rotates freely. In response to subsequent decreasing pressure of drilling fluid in the mandrel, the guide lug moves downwardly and engages the alignment sleeve, so that the eccentric sleeve—mounted to the alignment sleeve—rotates to a known position with respect to the mandrel.
BRIEF DESCRIPTION OF DRAWINGS
The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will be understood best by reference to the following detailed description of an illustrative embodiment when read in conjunction with the accompanying drawings, wherein:
FIG. 1 depicts a drill string employing the present invention on the lower end thereof;
FIG. 2 depicts a longitudinal view of a portion of a drill string embodying the present invention;
FIG. 3A depicts a longitudinal sectional view taken along line 3 A- 3 A of FIG. 2 ;
FIG. 3B depicts a longitudinal sectional view taken along line 3 B- 3 B of FIG. 2 ;
FIG. 3C depicts a longitudinal sectional view taken along line 3 C- 3 C of FIG. 2 ;
FIG. 3 A′ depicts a view similar to FIG. 3A showing the changed positions of certain elements as a result of an increased fluid pressure in the drill string;
FIG. 3 B′ depicts a view similar to FIG. 3B showing the changed positions of certain elements as a result of an increased fluid pressure in the drill string;
FIG. 4 is a cross-sectional view taken along line 4 - 4 of FIG. 3A ;
FIG. 5 is a cross-sectional view taken along line 5 - 5 of FIG. 3B ;
FIG. 6A is a cross-sectional view taken along line 6 A- 6 A of FIG. 3B ;
FIG. 6B is a cross-sectional view taken along line 6 B- 6 B of FIG. 3 B′;
FIG. 7A is a top perspective exploded view of the upper mandrel and sliding tube associated with the present invention;
FIG. 7B is a top perspective exploded view of the upper external bearing assembly associated with the present invention;
FIG. 7C is a top perspective exploded view of the eccentric sleeve, deflection device, and alignment mechanism associated with the present invention; and
FIG. 7D is a top perspective exploded view of the lower mandrel and lower external bearing assembly associated with the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
As used herein, “fluid” means a source or means of supplying pressure and shall include without limitation hydraulic fluid, water, high-pressure compressed air, and similar sources of pressure.
Referring now to FIG. 1 , there is shown well bore 1 comprising the vertical borehole 2 , non-linear borehole 3 , and horizontal borehole 4 , described above. Well bore 1 extends downwardly beneath the surface of the ground through numerous and varied subterranean strata, some of which may be oil-bearing. Drill string 5 extends vertically downward in well bore 1 and connects with drill pipe 16 . Drill pipe 16 , in turn, connects to the improved rotary steerable tool 10 of the present invention.
FIG. 2 depicts the improved rotary steerable tool 10 of the present invention, which has been modified and ported in a manner later to be described. Rotary steerable tool 10 has upper mandrel 20 with female threads 12 on one end that mate with male threads 14 on the end of a drill pipe, such as drill pipe 16 . Rotary steerable tool 10 further comprises lower mandrel 50 with male threads 52 on one end that mate with female threads 42 on the end of a second piece of drill pipe, such as drill pipe 54 . Upper mandrel 20 and lower mandrel 50 have an outer cylindrical surface that receives eccentric sleeve 32 . Drill pipes 16 and 54 (not shown in further detail) are a portion of a plurality of vertical drill pipes that have been connected together to make a semi-rigid drill string, familiar to those of ordinary skill in the art. Alternatively, drill pipe 54 can be another drill pipe sub-assembly, or a drill motor, including air-driven hammer motors and fluid-driven progressive cavity pumps (commonly known as “mud motors”). Rotary steerable tool 10 is depicted in use within borehole 1 in earth 22 , and external bearing assemblies 27 and 45 (described in detail below) isolate drill pipe 54 and rotary steerable tool 10 from borehole 1 .
The interior of upper mandrel 20 is hollow, forming an upper bore 24 . The end of upper bore 24 adjacent to female threads 12 is funnel shaped in the current embodiment. Alignment lug 26 is inserted into hole 56 (not shown), which communicates with upper bore 24 . Upper external bearing assembly 27 encircles upper mandrel 20 . Eccentric sleeve 32 encircles the lower end of upper mandrel 20 and the upper end of lower mandrel 50 . Deflection pad 36 rests in recess 100 . Retaining bolts 38 attach pistons 40 to the underside of deflection device 36 . The upper end of lower mandrel 50 directly below eccentric sleeve 32 has two holes 44 (only one of which is visible). Lower external bearing assembly 45 encircles lower mandrel 50 .
FIG. 3A depicts the upper portion of rotary steerable tool 10 . The hollow interior of upper mandrel 20 forms part of mandrel channel 25 , which comprises upper bore 24 and lower bore 158 . The diameter of upper bore 24 is less than the diameter of lower bore 158 , so that mandrel shoulder 160 is formed where upper bore 24 meets lower bore 158 in mandrel channel 25 . Alignment lug 56 is located near the joint between rotary steerable tool 10 and upper mandrel 20 . Alignment lug 56 extends into mandrel channel 25 and is aligned vertically with deflection pad 36 (see FIG. 2 ) so that an alignment tool lowered from the surface can engage alignment lug 56 and determine the orientation of deflection pad 36 . Control tube 60 is mounted for sliding movement within mandrel channel 25 of upper mandrel 20 , making control tube 60 responsive to pressure from fluid flowing through the drill string, as will be described hereinafter. Control tube 60 is hollow, having tube channel 63 that allows fluid to flow freely through control tube 60 . Upper portion 152 of control tube 60 is shown, with control spring 62 encircling it within lower bore 158 . One end of control spring 62 rests against mandrel shoulder 160 . O-ring 58 prevents leakage between upper portion 152 and upper mandrel 20 . In comparison to prior art devices such as the rotary steerable tool described in the '321 patent, the orientation of control tube 60 improves the fluid dynamics of drilling fluid as it flows from mandrel channel 25 into tube channel 63 because the diameter of tube channel 63 is substantially the same as that of mandrel channel 25 , as seen in FIG. 3A . There is no measurable restriction in the flow of fluid through rotary steerable tool 10 .
FIG. 3B depicts the middle portion of rotary steerable tool 10 , including eccentric sleeve 32 , upper external bearing assembly 27 , and lower portion 154 of control tube 60 . Also seen in FIG. 3B is alignment sleeve 112 , which is fixed rigidly to the inside surface of eccentric sleeve 32 . Upper portion 152 of control tube 60 is attached to lower portion 154 , which has a larger outer diameter than upper portion 152 . The opposing end of control spring 62 rests against tube shoulder 61 , which is formed where lower portion 154 meets upper portion 152 . O-ring 96 prevents leakage between mandrel channel 25 and lower bore 158 . Lower portion 154 has hole 120 in its sidewall. Guide lug 122 is connected to hole 120 through slot 102 . Slot 102 is present in the middle portion of the sidewall of upper mandrel 20 . In the position shown in FIG. 3B , guide lug 122 also is engaged to alignment sleeve 112 so that control tube 60 , upper mandrel 20 , lower mandrel 50 , alignment sleeve 112 , and eccentric sleeve 32 rotate as a single unit with drill pipe 16 . Slot 102 is essentially equal in width to the diameter of guide lug 122 . The outer end of guide lug 122 terminates at or near the inner surface of eccentric sleeve 32 .
FIG. 3B also illustrates components of upper external bearing assembly 27 , which includes first collar 28 , first sleeve 30 , first bearing ring 68 , and second bearing ring 74 . First spacer 72 separates first bearing ring 68 from second bearing ring 74 , and all three components encircle upper mandrel 20 and are enclosed in first sleeve 30 . First collar 28 is engaged to first sleeve 30 . Second bearing ring 74 rests on retaining clip 78 . O-rings 86 , 88 , and 90 prevent leakage between borehole 1 and the internal components of upper external bearing assembly 27 . O-rings used in rotary steerable tool 10 , including upper external bearing assembly 27 , create a substantially frictionless seal. Low-friction O-rings are available from manufacturers such as Bal Seal Engineering Co. of California. Bearing rings 68 and 74 permit upper mandrel 20 to rotate freely with respect to upper external bearing assembly 27 , thereby isolating upper mandrel 20 from borehole 1 .
Referring again to FIG. 3B for illustration, eccentric sleeve 32 , which has thick wall 34 and thin wall 98 , encircles the lower portion of upper mandrel 20 below upper external bearing assembly 27 . Eccentric sleeve 32 also encircles second spacer 84 , which is positioned between eccentric sleeve 32 and upper mandrel 20 . Bearing ring 80 also is positioned between eccentric sleeve 32 and upper mandrel 20 , above second spacer 84 . Together with bearing ring 114 , which is positioned between eccentric sleeve 32 and upper mandrel 20 below alignment sleeve 112 , bearing ring 80 provides a low-friction surface that permits upper mandrel 20 to rotate freely with respect to eccentric sleeve 32 . O-ring 92 prevents leakage between borehole 1 and bearing ring 80 , and O-ring 94 prevents leakage between mandrel channel 25 and bearing ring 80 . Thick wall 34 of eccentric sleeve 32 defines recess 100 , which could be rectangular or circular in cross-section. Deflection device 36 rests within recess 100 and is attached to pistons 40 by retaining bolts 38 , each of which pass through piston chambers in eccentric sleeve 32 . The ends of pistons 40 opposing retaining bolts 38 have a slightly larger diameter than the diameter of the body of pistons 40 themselves, thereby creating a shoulder against which piston springs 104 engage pistons 40 . O-rings 106 encircle the opposing end of pistons 40 , preventing leakage between mandrel channel 25 and the piston chambers. Piston springs 104 encircle pistons 40 , with one end resting against washers 108 , and urge pistons 40 inwardly. Retaining ring 110 secures washer 108 against piston spring 104 .
Alignment sleeve 112 is hollow and has sloped surface 156 encircling the lower portion of upper mandrel 20 and lower portion 154 of control tube 60 . Sloped surface 156 terminates in a tip or point, and in side elevation, appears to be generally elliptical in shape (see FIG. 7C ). O-ring 124 prevents leakage between mandrel channel 25 and bearing ring 114 , and O-ring 126 prevents leakage between borehole 1 and bearing ring 114 . The upper portion of lower mandrel 50 has two holes 44 in its sidewall 180° apart. Holes 44 provide access to recesses 118 present in the lower portion of upper mandrel 20 .
FIG. 3C depicts the lower portion of rotary steerable tool 10 . Lower mandrel 50 is hollow with its upper portion joined to the lower portion of upper mandrel 20 by male threads 142 on upper mandrel 20 and female threads 144 within lower mandrel 50 . O-ring 164 prevents leakage between borehole 1 and mandrel channel 25 . Lower external bearing assembly 45 encircles lower mandrel 50 near the joint between lower mandrel 50 and upper mandrel 20 . Lower external bearing assembly 45 is comprised of components similar to the components of upper external bearing assembly. Lower external bearing assembly includes second collar 46 , second sleeve 48 , third bearing ring 130 , and fourth bearing ring 136 . Second spacer 134 separates third bearing ring 130 from fourth bearing ring 136 , and all three components encircle lower mandrel 50 and are enclosed in second sleeve 48 . Second collar 46 is engaged to second sleeve 48 . Fourth bearing ring 136 rests on retaining clip 140 . O-ring 162 and O-ring 128 prevent leakage between borehole 1 and third bearing ring 130 . O-ring 166 prevents leakage between borehole 1 and fourth bearing ring 136 . Like bearing rings 68 and 74 , bearing rings 130 and 136 permit lower mandrel 50 to rotate with respect to lower external bearing assembly 45 , thereby isolating lower mandrel 50 from borehole 1 . Threads 52 are present on the lower portion of lower mandrel 50 to connect lower mandrel 50 to the upper portion of drill pipe 54 .
FIG. 3 A′ depicts the upper portion of rotary steerable tool 10 in a pressurized state. As used herein, the term “pressurized state” refers to any state in which the pressure of the fluid flowing through mandrel channel 25 is greater than the pressure that control spring 62 exerts on control tube 60 . In operation, fluid is introduced into upper bore 24 of upper mandrel 20 by drill pipe 16 . Once sufficient pressure accumulates to overcome control spring 62 , control tube 60 is pushed towards the upper portion of upper mandrel 20 , compressing control spring 62 .
FIG. 3 B′ also depicts a portion of rotary steerable tool 10 in a pressurized state. As lower portion 154 of control tube 60 translates upward in upper mandrel 20 , guide lug 122 in hole 120 also translates from the lower end of slot 102 to the upper end of slot 102 , and guide lug 122 disengages from alignment sleeve 112 . Moreover, as depicted in FIG. 3 B′, guide lug 122 translates beyond alignment sleeve 112 so that upper mandrel 20 and lower mandrel 50 rotate freely within alignment sleeve 112 and eccentric sleeve 32 . The upward movement of control tube 60 permits pressurized fluid to flow through slot 102 and exert pressure on pistons 40 . Once sufficient pressure is exerted on pistons 40 to overcome the resistance of piston springs 104 , piston springs 104 are compressed between the shoulders of pistons 40 and washers 108 , and deflection pad 36 is pushed out from recess 100 in thick wall 34 of eccentric sleeve 32 . At this point, deflection pad 36 will bear against the side of borehole 1 , locking eccentric sleeve 32 in a fixed lateral position against the side of borehole 1 . Deflection pad 36 pushes thin wall 98 of eccentric sleeve 32 toward the side of borehole 1 opposite deflection pad 36 , thereby causing the lower end of the drill string to tilt away from the longitudinal axis of borehole 1 above rotary steerable tool 10 . Deflection pad 36 also forces external bearing assemblies 27 (see FIG. 3B) and 45 (see FIG. 3C ) toward the side of borehole 1 opposite deflection pad 36 . Since external bearing assemblies 27 and 45 minimize the contact of borehole 1 with drill pipe 16 and the other components of rotary steerable tool 10 , the propensity of rotation forces collapsing deflection pad 36 is reduced in this pressurized state. Moreover, the outer surface of deflection pad 36 can be smooth or grooved, but does not require grooves to keep rotary steerable tool 10 from rotating as the drilling operation proceeds.
Once the back pressure dissipates, control spring 62 returns control tube 60 and guide lug 122 to the positions depicted in FIG. 3B . Alignment sleeve 112 realigns deflection pad 36 and eccentric sleeve 32 into the positions depicted in FIG. 3B as well. Likewise, piston springs 104 return pistons 40 and deflection device 36 to the positions within recess 100 depicted in FIG. 3B . The position of the components depicted in FIG. 3C are unaffected by the presence or absence of back pressure exerted by a fluid within upper bore 24 and lower bore 34 of rotary steerable tool 10 .
FIG. 4 is a cross-sectional view of the upper portion of rotary steerable tool 10 (see FIG. 3A ) in an un-pressurized state. Deflection pad 36 resides within thick wall 34 of eccentric sleeve 32 . Eccentric sleeve 32 and first sleeve 30 isolate upper mandrel 20 from borehole 1 in earth 22 . First collar 28 is attached to first sleeve 30 . Control spring 62 encircles upper portion 152 of control tube 60 .
FIG. 5 is a cross-sectional view of upper mandrel 20 encircled by first sleeve 30 in an un-pressurized state. Deflection pad 36 resides within thick wall 34 of eccentric sleeve 32 . Eccentric sleeve 32 and first sleeve 30 isolate upper mandrel 20 from borehole 1 in earth 22 . Bearings 76 within second bearing ring 74 permit upper mandrel 20 to rotate with respect to first sleeve 30 . First spacer 72 separates second bearing ring 74 from first bearing ring 68 (not shown). Control spring 62 encircles upper portion 152 of control tube 60 .
FIG. 6A is a cross-section of upper mandrel 20 encircled by eccentric sleeve 32 in an un-pressurized state. Deflection pad 36 resides within thick wall 34 of eccentric sleeve 32 . Retaining bolt 38 attaches deflection pad 36 to piston 40 . Piston spring 104 encircles piston 40 and has one end resting against washer 108 . Retaining ring 110 secures washer 108 against piston spring 104 , and O-ring 106 prevents leakage between piston 40 and eccentric sleeve 32 . Eccentric sleeve 32 and second sleeve 48 isolate upper mandrel 20 from borehole 1 in earth 22 . Upper mandrel 20 has slot 102 in its sidewall, which is isolated from mandrel channel 25 by control tube 60 .
FIG. 6B is a cross-section of upper mandrel 20 encircled by eccentric sleeve 32 in a pressurized state. Lower portion 154 of control tube 60 (not shown) has been displaced by fluid pressure, exposing fluid in mandrel channel 25 to slot 102 and sleeve channel 33 . The fluid then exerts pressure on piston 40 , which pushes deflection pad 36 out from recess 100 in thick wall 34 of eccentric sleeve 32 . Deflection pad 36 engages one side of borehole 1 in earth 22 and urges thin wall 98 against the opposite side of borehole 1 , thereby tilting the drill string away from the longitudinal axis of borehole 1 . Retaining bolt 38 attaches deflection pad 36 to piston 40 . Piston spring 104 encircles piston 40 and has one end resting against washer 108 . O-ring 106 prevents leakage between the piston chamber and mandrel channel 25 . Eccentric sleeve 32 and second sleeve 48 isolate upper mandrel 20 from borehole 1 in earth 22 . Alignment sleeve 112 is shown partially encircling upper mandrel 20 . The translation of lower portion 154 of control tube 60 (not visible) has lifted guide lug 122 above tapered end 156 (see FIG. 3 B′), thereby permitting upper mandrel 20 to rotate freely within alignment sleeve 112 and eccentric sleeve 32 .
FIG. 7A is an exploded view of upper mandrel 20 and control tube 60 associated with the present invention. Upper mandrel 20 is hollow with female threads 12 in its interior at one end and male threads 142 on the exterior of the opposing end. Hole 56 is present in its sidewall below female threads 12 for receiving alignment lug 26 (not shown), and slot 102 is present in its sidewall above male threads 142 . Hole 56 and slot 102 are vertically aligned with each other. Control tube 60 has control spring 62 encircling upper portion 152 . One end of control spring 62 rests against tube shoulder 61 on lower portion 154 , which has a larger outer diameter than upper portion 152 . Lower portion 154 has hole 120 in its sidewall for receiving guide lug 122 (not shown). Upper portion 152 is inserted into upper mandrel 20 when rotary steerable tool 10 is assembled.
FIG. 7B is an exploded view of upper external bearing assembly 27 associated with the present invention. First collar 28 has male threads 66 on one end that attach to female threads 64 in one end of first sleeve 30 when rotary steerable tool 10 is assembled. First bearing ring 68 fits below first collar 28 and is separated from second bearing ring 74 by first spacer 72 . Second bearing ring 74 is separated from first sleeve 30 by retainer 78 . Third bearing ring 80 sits above spacer 84 . Third bearing ring 80 separates the upper end of eccentric sleeve 32 from upper mandrel 20 when rotary steerable tool 10 is assembled.
FIG. 7C is an exploded view of eccentric sleeve 32 , deflection pad 36 , and alignment sleeve 112 associated with the present invention. Eccentric sleeve 32 is hollow with recess 100 in thick wall 34 . Eccentric sleeve 32 has thin wall 98 opposite thick wall 34 . Recess 100 receives pistons 40 , piston springs 104 , washers 108 , retaining rings 110 , and deflection pad 36 when rotary steerable tool 10 is assembled. Retaining bolts 38 attach deflection pad 36 to pistons 40 . Piston springs 104 exert pressure against the shoulder of pistons 40 to retain deflection device 36 within recess 100 when eccentric sleeve 32 is un-pressurized.
Alignment sleeve 112 has sloped surface 156 on one end and bearing ring 114 beneath its opposing end. Sloped surface 156 terminates in a point and has a generally elliptical shape when viewed at elevation from its side. Alignment sleeve 112 is attached to the inside of eccentric sleeve 32 by any convenient method, such as welding. Alternatively, alignment sleeve 112 and eccentric sleeve 32 can be machined as a single piece.
FIG. 7D is an exploded view of lower mandrel 50 and lower external bearing assembly 45 associated with the present invention. Lower mandrel 50 is hollow with male threads 52 on the exterior of one end. The end opposite male threads 52 receives male threads 142 of upper mandrel 20 (see FIG. 7A ) when rotary steerable tool 10 is assembled. Third collar 46 has male threads 146 on one end that attach to female threads 148 in one end of sleeve 48 when rotary steerable tool 10 is assembled. Third bearing ring 130 fits below collar 46 and is separated from fourth bearing ring 136 by spacer 134 . Fourth bearing ring 136 is separated from second sleeve 48 by retainer 140 .
With respect to the above description, it is to be realized that the optimum dimensional relationship for the parts of the invention, to include variations in size, materials, shape, form, manner of operation, assembly, and use are deemed readily apparent and obvious to one of ordinary skill in the art. The present invention encompasses all equivalent relationship to those illustrated in the drawings and described in the specification. The novel spirit of the present invention is still embodied by reordering or deleting some of the steps contained in this disclosure. The spirit of the invention is not meant to be limited in any way except by proper construction of the following claims. | The invention is an improved rotary steerable tool. The improved rotary steerable tool comprises a control tube that slides vertical within a mandrel in response to changes in drilling fluid pressure, thereby opening and closing a channel between the mandrel and a piston chamber in a rotationally isolated sleeve. With the channel open, a piston in the piston chamber is exposed to the drilling fluid. When the drilling pressure is sufficient to cause the piston to move, the piston forces a deflection pad outward. After the deflection pad engages a borehole wall, any additional increases in pressure force the opposing side of sleeve toward the opposite wall, thereby tilting the direction of any attached drill bit. An optional guide lug and alignment sleeve orient the deflection pad with respect to other components. | 4 |
RELATED APPLICATIONS
There are no current co-pending applications.
FIELD OF THE INVENTION
The present invention is directed to roofing materials and supplies. More particularly, this invention relates to self-sealing roofing fasteners having a pointed fastener shaft, a fastener head, and a sleeve with a rupturing shell that contains a volume of sealant and which is disposed over the shaft and adjacent the head.
BACKGROUND OF THE INVENTION
One (1) of America's major economic activities is construction. Buildings need to be planned, financed, erected, torn down, moved, wired, re-wired, refurbished, remodeled, and enlarged. Anyone involved in the physical aspects of construction can testify to just how strenuous construction is, whether it is carpentry, bricklaying, foundation work or just about any other task associated with construction.
One (1) particularly difficult and dangerous construction task is roofing. A roofer typically carries heavy loads, endures high temperatures, and climbs steep ladders and roofs at dangerous elevations. A roofer usually lays a protective coated paper underlay over wood flooring and then lays shingles or other roofing material over the coated paper. The various layers are typically nailed down using roofing fasteners such as nails. One (1) task that must often be performed is sealing the roofing fasteners with tar after they have installed the various roofing materials. Sealing is not only messy, but takes time, which results in lost profits. Should the roofing fasteners not be properly sealed roof leaks may result, causing warranty work and unhappy customers.
Accordingly, there exists a need for self-sealing roofing fasteners that can be quickly and easily installed. Such self-sealing roofing fasteners would automatically seal nail holes when the fastener is installed. This would eliminate having to stop and seal the nail holes or to go back and seal them afterwards. That would save time and money, resulting in a higher quality job with minimal work. Beneficially self-sealing fasteners would be suitable for use with both existing nail guns and hammers, would be available in a range of different lengths and styles, and would reduce the mess of sealing nail holes.
SUMMARY OF THE INVENTION
The principles of the present invention provide for self-sealing roofing fasteners that automatically seal nail holes when the self-sealing roofing fasteners are installed. Such roofing fasteners can be implemented for use with existing nail guns and hammers and can be made available in a range of different lengths and styles.
A self-sealing fastener that is in accord with the present invention includes a fastener head, a fastener shaft that extends from the fastener head, and a sealing sleeve around the fastener shaft and adjacent the fastener head. The sealing sleeve includes an outer shell that retains a sealant. The self-sealing fastener maybe a hollow, cylindrical plastic form having an inner diameter that is dimensioned to fit snugly and permanently over the fastener shaft to restrict the flow of the sealant on the shaft. The sealant is beneficially an air-curable liquid sealing material such as tar or an adhesive.
A self-sealing fastener system that is in accord with the present invention includes a plurality of fasteners, each having a fastener shaft that extends from a fastener head and a sealing sleeve that is located around the fastener shaft and adjacent to said fastener head. Each sealing sleeve includes an outer shell that retains a sealant. A pair of parallel coil wires connects the plurality of fasteners into a coil of fasteners. Each sealing sleeve is a hollow, cylindrical plastic form having an inner diameter that is dimensioned to fit snugly and permanently over a fastener shaft to restrict the flow of the sealant on the shaft. The sealant is beneficially an air-curable liquid sealing material such as tar or an adhesive.
An alternative self-sealing fastener that is in accord with the present invention includes a fastener head, a fastener shaft that extends from the fastener head, a sealant over the fastener shaft and adjacent the fastener head, and a coating over the sealant. The coating is preferably a sprayed on plastic material. The sealant is beneficially an air-curable liquid sealing material such as tar or an adhesive.
An alternative self-sealing fastener system that is in accord with the present invention includes a plurality of fasteners, each having a fastener head, a fastener shaft that extends from the fastener head, a sealant over the fastener shaft and adjacent the fastener head; and a coating over the sealant. A pair of parallel coil wires connects the plurality of fasteners into a coil of fasteners. In practice the coating is a sprayed on plastic material. The sealant is beneficially an air-curable liquid sealing material such as tar or an adhesive.
BRIEF DESCRIPTION OF THE DRAWINGS
The advantages and features of the present invention will become better understood with reference to the following more detailed description and claims taken in conjunction with the accompanying drawings, in which like elements are identified with like symbols, and in which:
FIG. 1 is a perspective view of a coiled configuration of self-sealing fasteners 10 that are in accord with the principles of the present invention;
FIG. 2 a is a section view of a self-sealing fastener 10 taken along section line A-A of FIG. 1 ;
FIG. 2 b is section view of the self-sealing fastener 10 of FIG. 2 a after installation;
FIG. 3 is a perspective view of a spray coated fastener 120 embodiment that is in accord with the principles of the present invention; and,
FIG. 4 is a sectional view of the spray coated fastener 120 shown in FIG. 3 .
DESCRIPTIVE KEY
10 fastener
30 fastener shaft
32 fastener head
34 coil wire
40 sealing sleeve
42 outer shell
44 sealant
100 structure
120 spray-coated fastener
122 spray-coating
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The best mode for carrying out the invention is presented in terms of its preferred embodiment, which is depicted in FIGS. 1 , 2 a , and 2 b and in terms of an alternate embodiment, which is depicted in FIGS. 3 and 4 . However, the invention is not limited to the described embodiment, and a person skilled in the art will appreciate that many other embodiments of the invention are possible without deviating from the basic concept of the invention and that any such work around will also fall under scope of this invention. It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope.
The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced items.
Referring now to FIG. 1 , the principles of the present invention provide for self-sealing fasteners 10 that automatically seal respective penetration areas during installation of the fasteners 10 . The fasteners 10 are envisioned as taking the form of a roofing nail or similar fastener that is susceptible to producing a leak within a structure 100 (see FIG. 2 b ) after installation.
As shown in FIG. 1 , a plurality of fasteners 10 can be configured in the form of coiled roofing nails such as those used with standard pneumatic nail guns. As shown, each fastener 10 is welded to a pair of parallel coil wires 34 . Each fastener 10 comprises a sealing sleeve 40 that is inserted onto a fastener shaft 30 of the fastener 10 and positioned immediately adjacent a fastener head 32 . The sealing sleeve 40 aids in sealing holes made by the fastener 10 during installation. Referring now to FIG. 2 a , each fastener 10 is also envisioned as being made available as individual nails rather than as part of a spool. This enables a user to install the fasteners 10 with a hammer or similar tool.
Referring now to FIGS. 2 a and 2 b , the fastener 10 generally takes the form of a common roofing nail. The fastener 10 has a pointed cylindrical fastener shaft 30 and a perpendicularly extending fastener head 32 . While FIGS. 2 a and 2 b show rather plain nails, it should be understood that fasteners 10 may incorporate features such as ribbed or threaded fastener shafts, specialized fastener heads, and the like.
Still referring to FIGS. 2 a and 2 b , the fastener 10 also includes a sealing sleeve 40 having a hollow cylindrical shape with an inner diameter dimensioned to fit snugly and permanently over the fastener shaft 30 to restrict the flow of the sealant on the shaft. The sealing sleeve 40 has an outer shell 42 which provides containment and encapsulation of a core comprised of a sealant 44 . That sealant is envisioned as being an air-curable liquid sealing materials such as tar, various industrial adhesives, and the like. The outer shell 42 forms a thin and easily ruptured sealed barrier. It is envisioned that the outer shell 42 is made from polyvinylidene chloride, polyethylene, or the like. The sealing sleeve 40 is positioned immediately adjacent the fastener head 32 on the fastener shaft 30 .
Referring to FIG. 2 b , as the fastener 10 is driven through a structure 100 by the pneumatic nail gun or by a hammer, the outer shell 42 of the sealing sleeve 40 ruptures and deforms to release the contained sealant 44 . The sealant 44 seals the fastener head 32 and the structure 100 so as to provide a waterproof protective seal that prevents leakage over time.
Beneficially a plurality of the fasteners 10 may be configured for use with existing unmodified nail guns to perform new roofing jobs, replacement roofing jobs, as well as a variety of projects designed to cover a structure 100 .
Referring now to FIGS. 3 and 4 , perspective and section views of an alternate spray-coated embodiment 120 according to an alternate embodiment of the present invention, are disclosed. In lieu of the outer shell 42 to contain the sealant 44 , the spray-coated embodiment 120 provides a spray-coating 122 that contains and positions the sealant 44 . The spray-coating 122 comprises a sprayed-on or similarly applied material such as latex, vinyl, various sprayed adhesives, or the like. The spray-coating 122 is thin enough to enable rupturing to release the sealant 44 .
It is envisioned that other styles and configurations of the present invention can be easily incorporated into the teachings of the present invention, and only one particular configuration shall be shown and described for purposes of clarity and disclosure and not by way of limitation of scope.
The preferred embodiment of the present invention can be utilized by the common user in a simple and effortless manner with little or no training. After initial purchase or acquisition of the fastener 10 , it would be installed as indicated in FIG. 1 or alternately in FIG. 4 .
The method of utilizing the preferred embodiment of the fastener 10 may be achieved by performing the following steps: procuring the fastener 10 in a desired fastener style and individual or coiled format based upon a particular building project and fastener driving method; utilizing the fastener 10 to secure materials such as shingles, metal roofing, cedar shakes, rolled roofing, siding, and other building materials, in a conventional manner to a structure 100 comprising sheathing, wall coverings, and the like; providing a sealing of the materials and structure 100 via the coincidental collapsing of the sealing sleeve 40 and the penetration of the fastener 10 into the structure 100 ; and, benefiting from avoidance of possible damage due to leakage commonly associated with penetrating installation of fasteners. The method of utilizing the alternate spray coated embodiment 120 may be accomplished in like manner as the preferred embodiment 10 described above.
The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. | A self-sealing roofing nail for reducing or preventing roof leaks. The self-sealing roofing fastener includes a pointed fastener shaft and a fastener head. A small sleeve having a rupturing shell containing a volume of sealant is disposed over the fastener shaft and adjacent the fastener head. When the self-sealing roofing fastener is driven into a structure using a hammer or a nail gun, the shell ruptures and releases the sealant between the fastener head and a structure. The released sealant seals the puncture caused by driving the roofing fastener into the structure. | 4 |
This application is related to issued U.S. Pat. No. 6,622,720 entitled “Using Capillary Wave Driven Droplets to Deliver a Pharmaceutical Product”, and patent application Ser. No. 09/739,989 entitled “A Method of Using Focused Acoustic Waves to Deliver a Pharmaceutical Product”. All Applications were filed on Dec. 18, 2000 and all Applications are assigned to the same Assignee.
BACKGROUND OF THE INVENTION
Many pharmaceutical products or drugs that provide relief from nasal or lung ailments are delivered through the respiratory system. In order to deliver these drugs, typically, the drug is compressed in a container. Users release the compressed pharmaceutical by opening a valve for a brief interval of time near the user's mouth or nose. Pump mechanisms may also be used to directly spray the pharmaceutical into the user's mouth or nose. The user may then draw a breath to further inhale the pharmaceutical product.
These techniques for delivering pharmaceuticals pose several problems. The first problem is that the droplet size produced is typically too large to be carried in an air stream generated by a normal intake of breath. Thus, in order to transport the larger droplets of pharmaceutical products, the product is propelled into the orifice. This may be done by using compressed air or by expelling the pharmaceutical product into the orifice at a high speed.
Unfortunately, a fast moving particle, defined as a particle that is moving much faster than the accompanying airstream, cannot easily travel around bends that occur in the human respiratory system. Thus, when the traditional means of injecting pharmaceuticals into the mouth are used, much of the pharmaceutical product is deposited on the back of the mouth or in the throat. The deposited pharmaceutical product may then be ingested into the digestive tract instead of the respiratory system. The ingested pharmaceutical product represents lost or wasted medication.
A second problem is that the varying amounts of lost pharmaceutical product makes it difficult to control dosages. Wasted droplets of medication that are deposited on the back of the throat makes it possible that the patient will receive insufficient medication. Determining the amount wasted and trying to compensate for the wasted medication is a difficult and inexact process.
Thus an improved method and apparatus of delivering pharmaceutical products to a patient's respiratory system is needed.
SUMMARY OF THE INVENTION
In order to more efficiently deliver pharmaceutical products, acoustic ink printing (AIP) technology has been adapted for use in delivering medications to a patient. In one embodiment of the invention, a liquid medication is distributed over several acoustic ejector drivers. The drivers are inserted into or placed in close proximity to an orifice of the patient such as the mouth or the nose. A power source provides energy to each driver. The drivers convert the energy into focused acoustic waves that cause small droplets of medication to be ejected into the orifice. Air currents distribute the medication throughout the patient's respiratory system.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a cross section of a droplet ejector in an array of droplet ejectors ejecting a droplet of pharmaceutical product.
FIG. 2 shows ejection of droplets using capillary action.
FIG. 3 shows one embodiment of forming an inhaler that uses a single transducer to drive multiple droplet sources.
FIG. 4 shows an example distribution of droplet ejectors on an inhaler head.
FIG. 5 shows a cross sectional side view of one embodiment of an inhaler designed for insertion into the mouth of a patient.
FIG. 6 shows the inhaler in use by a patient.
DETAILED DESCRIPTION OF THE INVENTION
An inhaler system that adapts acoustic ink printing technology to output small droplets of pharmaceutical product at a low velocity is described. The droplets are preferably less than 10 micrometers in diameter. Small droplet size and an output speed approximately matching the rate of airflow into the respiratory system maximizes the quantity of medication administered to a patient's lungs.
FIG. 1 shows an array 160 of droplet sources such as droplet sources 100 , 101 , 102 , 103 for use in an inhaler 144 . Each droplet source 100 , 101 , 102 , 103 is capable of outputting droplets of pharmaceutical product. Inhaler 144 is designed such that the combined output of all droplets sources in array 160 over a predetermined period of time are sufficient to deliver a desired volume of pharmaceutical product to a patient. The pharmaceutical product is typically liquid that contains organic compounds for deposition in the lungs of the patient.
FIG. 1 includes a cross sectional view of one example droplet source 100 in array 160 . The cross sectional view also shows a distribution of a reservoir of pharmaceutical product 108 shortly after ejection of a droplet 104 and before a mound 112 on a free surface 116 has relaxed. A radio frequency (RF) source 120 provides a RF drive energy to a driver element such as a transducer, typically a piezo-electric transducer 124 , via bottom electrode 128 and top electrode 132 . The acoustic energy from the transducer passes through base 136 into an acoustic lens 140 . Acoustic lens 140 focuses the received acoustic energy into a focused acoustic beam 138 that terminates in a small focal area near free surface 116 . In the illustrated embodiment, each droplet source in array 160 of droplet sources includes a corresponding acoustic lens and transducer to form an array of acoustic lenses and transducers.
Traditional acoustic ink printers usually use RF drives with frequencies of around 100 to 200 Megahertz (MHz). However, when droplet sources are used in inhalers, higher frequencies are preferred because higher frequencies generate smaller droplets that are more easily carried by air currents into the respiratory tract. Droplet sizes are typically on the order of the wavelength of the bulk acoustic wave propagating in the pharmaceutical product. This wavelength may be determined by dividing the velocity of sound for bulk wave propagation in the pharmaceutical product by the frequency of the bulk acoustic wave. Thus by increasing frequency, droplet size can be reduced A RF drive frequency exceeding 300 MHz typically results in the generation of droplets smaller than 5 micro-meters in diameter. Thus inhalers that directly eject droplets preferably operate in frequency ranges exceeding 300 MHz.
Higher frequencies used in inhaler droplet sources also result in higher power losses. Power losses in a droplet source are approximately proportional to the square of the frequency. Power losses in a droplet source are also proportional to the distance “d” from the top surface 141 of acoustic lens 140 to free surface 116 of the pharmaceutical product reservoir. In order to compensate for increased power losses due to the increased operating frequencies, distance “d” may be reduced compared to traditional AIP print heads. In inhaler applications, a distance “d” less than 150 micrometers may be used to conserve power.
A more detailed description of the droplet source or “droplet ejector” operation in a traditional AIP printhead is provided in U.S. Pat. No. 5,565,113 by Hadimioglu et al. entitled “Lithographically Defined Ejection Units” issued Oct. 15, 1996 and hereby incorporated by reference.
FIG. 1 uses focused acoustic energy to directly eject a droplet. FIG. 2 shows an alternative method of generating droplets using capillary action. When generating capillary wave-driven droplets, the principle mound 204 does not receive enough energy to eject a droplet. Instead, as the principle mound 204 decreases in size, the excess liquid is absorbed by surrounding capillary wave crests or side mounds 208 , 212 , 216 , 220 . These wave crests eject a mist corresponding to droplets 224 , 228 , 232 , 236 . In order to generate capillary action droplets instead of focused, single ejection droplets, each ejector transducer generates shorter pulse widths at a higher peak power. Example pulse widths are on the order of 5 microseconds or less when the transducer provides a peak power of approximately one watt or higher per ejector.
One advantage of using capillary action is the lower frequencies that can be used to create smaller droplets. The diameter of capillary generated droplets is similar in magnitude to the wavelength of capillary waves. The wavelength of capillary waves can be determined from the equation: wavelength=[2*Pi*T/(ro*f^2)]^(⅓) wherein T is the surface tension of the pharmaceutical fluid, ro is the density of the pharmaceutical fluid and f is the frequency output of the transducer. This equation and a more detailed explanation are provided on page 328 of Eisenmenger, Acoustica, 1959 which is hereby incorporated by reference. At typical densities and surface tensions, frequencies of below 15 MHz are typically used. Frequencies of 10 Megahertz (MHz) typically generate a capillary wavelength of 1.5 micrometers and a frequency of 1 MHz typically generates a capillary wavelength of 6.8 micrometers. Thus it is possible to generate approximately 5 micrometer diameter droplets at RF frequencies about two orders of magnitude smaller than the bulk waves used to generate “conventional” AIP droplets.
In capillary wave droplet systems, the lower frequencies used allows more flexibility in materials and tolerances used to fabricate transducers and acoustic lenses used to form the array of droplet sources. For example, plastics are not as lossy at the lower frequencies. The lower loss levels allow relatively inexpensive molded plastic spherical lenses to be used as acoustic lenses.
A second method of minimizing the cost of fabricating an array of droplet sources is to replace the plurality of transducers with a single transducer, the energy from the single transducer distributed to multiple lenses corresponding to multiple droplet sources. FIG. 3 shows an example of such a single transducer structure. In FIG. 3 , each droplet source corresponds to an acoustic lens such as acoustic lenses 308 , 312 , 316 . The acoustic lenses are positioned over a single large transducer 304 . Each acoustic lens independently focuses a portion of the bulk planar wave produced by single large transducer 304 to create droplets across a free surface 320 . Using a single transducer instead of the multiple transducers shown in FIG. 1 substantially reduces the cost associated with multiple transducers and the electronics to drive multiple transducers.
The number of droplet sources in an array of droplet sources may vary and typically depends on the dosages that will be administered. A typical five micron diameter drop of pharmaceutical product contains about 0.07 picoliters of fluid. Assuming a repetition rate of 200 KHz, a rate easily achievable with the typical ejector, each droplet source will deliver approximately 14 microliters per second. To administer medication at the rate of 100 milliliters per second, a typical number of ejectors may be around 7,000.
FIG. 4 shows a top view 404 of an example distribution of droplet sources 408 . Typically, the droplet sources are mounted on a circular head 412 over a distance of approximately 10 centimeters to facilitate insertion into an oral cavity. Alternative configurations of droplet sources may be designed for insertion into a nasal cavity. Although a circular pattern of droplet sources best utilizes the surface area of circular head 412 , in high viscosity pharmaceutical products, the flow of the product evenly across a circular pattern may prove difficult. Thus, in an alternate embodiment, a more linear pattern of droplet sources may be used.
Prevention of contamination, both from airborne particulate matter as well as organic matter such as bacteria is an important concern with the inhaler. Typically, openings 414 in circular head 412 are substantially larger than the droplet size ejected. For example, a typical opening size for ejection of a 10 micron diameter droplet may be approximately 100 microns. When droplet sources are not activated, the pharmaceutical product is maintained within the circular head 412 via surface tension across opening 414 . The relatively large exposed surface area of opening 414 may allows dust and other particulate matter to enter the openings and contaminate the pharmaceutical product.
A cover 413 that fits over the circular head 412 helps minimize particulate contamination. In one embodiment opening and closing cover 413 may switch on and off the inhaler. An alternate method of avoiding contamination uses micro electromechanical structure (MEMS) covers 416 positioned over each opening. MEMS cover 416 may open for a short time interval allowing droplets to be ejected and remain closed during other time periods. In one embodiment, the cover, whether a large area cover or a MEMS covers, may be electronically controlled such that the ejection of droplets causes the cover to automatically retract out of the path of the ejected droplets. Such electronic control may be achieved by synchronizing a cover control with the electrical impulse driving the transducers.
Besides particulate contamination, bacterial contamination should also be minimized. One method of controlling bacterial contamination is to regularly sterilize the ejector head using UV radiation. However, may patients do not have the discipline to regularly sterilize the ejector head. One method of forcing a regular sterilization schedule is to automatically expose the ejector heads to UV radiation whenever the inhaler power supply is being recharged.
Often, even with sterilization and covers, some contamination of the ejector heads over time is inevitable. Furthermore, when Fresnel zone plates are used as acoustic lenses, the ejector may be hard to clean making it difficult to use the same ejector head with several different medications. Plastic spherical lenses are easier to clean and can be used at lower frequencies, such as are typically associated with a capillary action droplet ejector. In systems where several different medications are being administered or where the ejector becomes otherwise contaminated, the ejector head 420 detaches from a body of the inhaler and can be replaced by a replacement head or a disposable ejector head. A clip-on or other fastener mechanism attaches ejector head 420 to the body. In one embodiment of the invention, an ultraviolet (UV) radiation source 430 sterilizes ejector head 420 .
FIG. 5 shows a cut away side view of one embodiment of inhaler 500 including ejector head 504 and body 508 . Electrical conductors 512 connect each piezoelectric element 516 in ejector head 504 to a power source 520 when a switch 524 is closed. The power source may be a battery such as an alkaline or nickel/cadmium battery.
A typical ejector uses approximately two nanojoules of acoustic energy at the liquid surface per drop of liquid ejected. Multiplying the power needed at the liquid surface by the loss factor of the ejector results in an approximate power requirement of 20 nanojoules per ejector at the ejector head. The total power used is calculated by multiplying the power per ejector at the ejector head by the total number of ejectors. To deliver a 100 microliter dose five times a day, the total power requirement is approximately 140 joules which is well within the power capabilities of most batteries, including most rechargeable nickel/cadmium batteries.
In one embodiment of the invention, a handle 527 of the AIP inhaler includes a container that stores a reservoir 525 of medication. When the ejector head is attached to the inhaler body, a pipe 529 , typically a hypodermic needle punctures a seal 531 that seals the reservoir 525 of medication. Typically, seal 531 is a rubber gasket that covers a section of the container of medication. A second pressurization needle 533 also punctures the rubber gasket and pumps gas into reservoir 525 slightly pressurizing the medication. The applied pressure should be sufficient to force the medication up pipe 529 ; however, the pressure should not be excessive such that it breaks the surface tension at the openings of the ejector head. Breaking the surface tension will prematurely force medication from the openings of the ejector head. Pressure detection system 535 monitors the pressure differential between the ambient surroundings and the pressure inside reservoir 525 and maintains the desired pressure to keep fluid in the ejector head without breaking the surface tension of each opening.
When drops are to be ejected, ejection switch 524 is closed. Closing ejection switch 524 activates the ejectors on ejector head 504 for a predetermined time interval. In one embodiment the invention, switch 524 is a trigger 526 . After the droplet ejectors are placed in close proximity to an oral cavity, a patient presses trigger 526 closing of switch 524 . Closing switch 524 cause the ejection of medication. In a second implementation of a switch control, an airspeed detector 527 controls the closing of switch 524 . In particular, when an inhalation by the patient causes the speed of air around the ejectors to approximately match the expected speed of ejected droplets, the airspeed detector closes switch 524 . The matched air speed provides an optimal air current for carrying droplets from the ejector into a patient's lungs.
Dosage setting switch 528 allows the user to adjust the dosage of medication provided by adjusting the duration of ejector operation after switch 524 is closed. In the illustrated embodiment, dosage setting switch 528 controls timer 532 . Timer 532 determines a time duration over which power is provided to piezoelectric 516 . The time interval is typically proportional to the dosage set on dosage setting switch 528 . When all ejectors are fired, the time interval is typically the dosage divided by the total output of ejectors on ejector head 504 per unit time.
When small dosages are desired, the dosage setting switch 528 may be programmed to reduce the number of ejectors fired on ejector head 504 by adjusting a control signal. The control signal switches ejectors in drive circuit 536 . Reducing the number of ejectors fired reduces the output of pharmaceutical product per unit time. The duration of ejector firing may also be selected based on the droplet ejector switching mechanism. When an airspeed detector 527 is used, extension of the pharmaceutical discharge time may be undesirable. Instead, it may be desirable to maximize the ejection of droplets during a very short time interval to take advantage of the optimal air speed, thus typically all ejectors will fire for a fraction of a second. However, in trigger based or manual operation, it may be desirable to extend the time interval slightly to allow for imprecise synchronization between ejection of droplets and inhalation.
Drive circuit 536 provides the drive signal to the ejectors on ejector head 504 . In a simple implementation of drive circuit 536 , all ejectors are simultaneously activated. Thus, in one embodiment of the invention, all ejectors may be connected in parallel such that closing switch 524 results in simultaneous ejection of droplets from all ejectors. However, circumstances may dictate that all ejectors not be fired at once. For example, when power source 520 is low on energy and needs recharging, the electric current provided may be insufficient to fire all ejectors simultaneously. In such cases, the drive circuit may detect the lower power output and fire different ejectors at different times or switch some ejectors off altogether with a corresponding increase in time duration to allow dispensing of the recommended dosage. As previously described, a request for a very low dosage may also result in firing of less than all of the ejectors at once. System design my also dictate that not all ejectors are fired at once. Typically, RF power is power is switched on to a group of ejectors for a time duration, on the order of microseconds, and then switched off for several microseconds. In order to minimize the peak power requirements of the inhale when the RF power is switched off to the group of ejectors, a second group of ejectors may receive RF power. Thus in one embodiment, the drive circuit 536 includes a multiplexing circuit that may alternately switch groups of ejectors on and off and avoid overlapping firing times.
FIG. 6 illustrates the use of the inhaler by a human subject. In the illustrated embodiment, the patient 600 inserts the applicator or ejector head 604 of the inhaler 608 into an oral cavity 612 . After insertion of inhaler 608 , a finger such as a pointer or trigger finger 616 applies pressure to a switch 620 . Alternately, the inhalation of air causes an airspeed indicator to detect the airspeed in aperture 624 and trigger a switch when the airspeed reaches a desired value. Under either implementation, the switch closes at a particular point in time causing power to be provided to the ejectors for a preset time duration and the ejection of a mist of medication into oral cavity 612 .
As the mist of medication is produced, the patient deeply inhales. The inhalation causes air currents 628 to carry the droplets 632 of pharmaceutical product to the patient's lungs 636 where the pharmaceutical product is absorbed. The matching of the ejection speed of droplets 632 with the speed of air currents 628 and the small size of droplets 632 maximizes the percentage of pharmaceutical product that reaches lungs 636 and minimizes the percentage of pharmaceutical product deposited on the back of the throat 640 .
While the preceding invention has been described in terms of a number of specific embodiments, it will be evident to those skilled in the art that many alternatives, modifications and variations may be performed while still remaining within the scope of the teachings contained herein. For example, specific power consumption of ejectors, ejector arrangements, methods of switching on the ejectors and methods of maintaining sterility of the inhaler have been described. However, such details should not be used to limit the scope of the invention and are merely provided to serve as examples for performing the claimed invention and lend clarity to the description. Accordingly, the present invention should not be limited by the embodiments used to exemplify it, but rather should be considered to be within the spirit and scope of the following claims and its equivalents, including all such alternative, modifications and variations. | An improved method and apparatus for delivering medication to the lungs is described. Acoustic ink printing technology is modified to operate as an inhaler that generates tiny droplets near a patient's nose or mouth. The tiny droplets are easily carried by air currents into the patient's lungs. The inhaler itself is preferably a battery operated portable device that can be easily carried and easily cleaned to avoid contaminating the medication. | 0 |
REFERENCE TO RELATED APPLICATIONS
[0001] This application is based on and claims priority to U.S. patent application Ser. No. 09/871,032, which claims priority to German Patent Application No. 10026788.2 filed May 31, 2000, and German Patent Application No. 10100273.4, filed Jan. 4, 2001. The entire content of each of these applications is incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The invention relates to an apparatus for controlling and monitoring aircraft cabin systems, for example the functions of the information, audio, video, lighting, door, water supply, or wastewater systems, and further relates to a method for operating the apparatus.
[0004] 2. Discussion of the Background
[0005] The operation and status of present day aircraft cabin systems are typically controlled and monitored from operating devices having simple input key panels and relatively small liquid crystal displays. With such operating devices, the functionality of the display and of the input keys is quite limited, or even strictly fixed to a respective single assigned function. In other words, there is little or no flexibility or adaptability of the present day conventional operating devices to accommodate changes of the respective cabin systems that are to be controlled or monitored. Therefore, the technical possibilities with regard to the expansion, flexibility, and adaptation to the most modem technologies are completely exhausted. There is a need to provide a more versatile, adaptable, user-friendly, and intuitively operable device for monitoring and controlling aircraft cabin systems.
SUMMARY OF THE INVENTION
[0006] In view of the above, it is an object of the invention to provide a device or arrangement of the above mentioned general type, which can be adapted to various prescribed requirements existing in any given application, for controlling and monitoring a variety of aircraft cabin systems from a single compact input and display arrangement. It is another object of the invention to provide a method for operating such a control and monitoring arrangement, which is user-friendly, intuitive, adaptable and reprogrammable to accommodate variations of the systems to be controlled and monitored. The invention further aims to avoid or overcome the disadvantages of the prior art, and to achieve additional advantages, as apparent from the present specification.
[0007] The above objects have been achieved according to the invention in a flight attendant operating device in the form of an input and display arrangement or interface panel comprising a liquid crystal display screen and a touch sensitive surface input arrangement. The liquid crystal display screen comprises a basic layout including a general display area as well as touch sensitive input keys embodied or provided with respective system and function symbols respectively associated with these input keys. The symbols may be words, letters, graphical icons, or any other identifying indicia. At least two system menus, which are respectively associated with two respective cabin systems, are provided as subordinate to the basic layout and can be displayed selectively on the general display area of the basic layout for selecting, controlling and monitoring the functions of the respective associated cabin system. As such, the respective individual system menus each operate as a system-specific window that can be selectively brought up in the display area of the basic layout. The system menus are thus virtual menus that may include virtual display areas and/or virtual input areas, and that may be selectively brought up and displayed in the display area of the basic layout.
[0008] All of the various menus or other features that are to be displayed in the display area of the basic layout can be generated, selected, arranged, and manipulated in any conventionally known manner by means of appropriate software and/or hardware, operating in the context of a computer system, which may be the general aircraft computer system, or a portion thereof, or a separate cabin system control computer. In response to the user inputs received from the inventive device, the computer then sends corresponding control command signals to the respective cabin systems to effectuate the desired control functions in any known manner.
[0009] According to further detailed embodiments, the invention provides for a main menu that can be displayed on the display area of the basic layout and that indicates the cabin status, i.e. the status of various systems or components within the cabin. Thereby, the main menu is provided or hierarchically arranged between the basic layout and the system menus. The main menu displays the essential information regarding the various cabin systems so that one or more of the cabin systems may be selected from a menu page of the main menu. The invention further preferably provides that the basic layout additionally includes, across the top of the basic layout, a header line or bar that identifies the respective active menu.
[0010] The above objects have further been achieved according to the invention in a method of operating the above described arrangement, including the following steps: p 1 a) an operator or user such as a flight attendant first touches or presses a desired system symbol on the basic layout or on the main menu so as to select and call up the respective associated main menu or subordinate system menu;
[0011] b) as a result, the selected main menu or system menu will be displayed on the general display area of the liquid crystal display screen; and
[0012] c) the operator then touches or presses respective pertinent function symbols displayed on the selected main menu or system menu, whereby these function symbols are respectively associated with prescribed operating functions of the pertinent selected system, in order to thereby select and/or adjust the desired operating functions of the respective associated selected cabin system.
[0013] The invention thus provides an apparatus whereby the flight attendant operating device may advantageously be universally adapted to various different respective requirements, by making use of touch sensitive screen technology. In other words, the display area of the basic layout is embodied as a touch sensitive screen, and can have various menus or windows displayed selectively thereon. The input keys of any system menu are essentially virtual input keys that can be displayed as needed for the various subsystems in the display area of the basic layout. Respective touch sensitive areas of the touch sensitive screen respectively in registration with the virtual displayed input keys will receive the touch inputs of the user.
[0014] Thereby, any given portion or area of the basic layout is not strictly dedicated to a particular function, but instead the display and input functions can be variably indicated or arranged on the basic layout as needed. Moreover, a required change of the display and/or input functions to accommodate a change or difference in the respective aircraft cabin systems can be achieved by simply reprogramming the software that generates the various displays and input functions. Such universal adaptability is directly linked to the required flexibility. Furthermore, the inventive arrangement provides a single, compact, versatile operator interface that makes it possible to control and monitor all of the relevant aircraft cabin systems from this single compact unit.
[0015] The inventive operating device or operator interface provides the following advantages:
[0016] a) easy user recognition of known functions and processes or sequences;
[0017] b) intuitively correct user inputs without requiring specialized training;
[0018] c) the possibility of reallocation and reuse of the same individual elements such as input keys, symbols, display fields, etc. to various different systems and/or functions;
[0019] d) by using a color display screen, it becomes possible to maintain a consistent color scheme or philosophy, i.e. using the same colors universally in connection with the same purpose, condition, status, or result to be achieved;
[0020] e) the display properties of the device can be adjusted or adapted to maintain good visibility under varying lighting conditions within the aircraft cabin; and
[0021] f) use of the fewest possible submenu planes for achieving a relatively flat hierarchy of the sub-menus or sub-windows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order that the invention may be clearly understood, it will now be described in connection with an example embodiment, with reference to the accompanying drawings, wherein:
[0023] [0023]FIG. 1 schematically shows the basic layout of an operating device according to the invention, including a liquid crystal display screen and a touch sensitive surface input arrangement;
[0024] [0024]FIG. 2 is a schematic diagram representing the interrelationships of the menu structure of the main menu and several subordinate system menus;
[0025] [0025]FIG. 3 schematically shows the appearance of the arrangement during a booting phase;
[0026] [0026]FIG. 4 schematically shows the main menu with five graphically displayed examples of subordinate cabin systems that can be selected;
[0027] [0027]FIG. 5 schematically shows a system menu associated with an audio system of the aircraft;
[0028] [0028]FIG. 6 schematically shows a system menu associated with a lighting system of the aircraft;
[0029] [0029]FIG. 7 schematically shows a system menu associated with all aircraft doors of the aircraft;
[0030] [0030]FIG. 8 schematically shows a system menu associated with the water supply and wastewater system of the aircraft;
[0031] [0031]FIG. 9 schematically shows a system menu for indicating the status of all of the cabin systems; and
[0032] [0032]FIG. 10 schematically shows a system menu for programming various functions of the cabin systems.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0033] [0033]FIG. 1 schematically shows the basic layout 1 of the operator surface or user interface of a flight attendant operating device, comprising a liquid crystal display screen in combination with a touch sensitive surface input arrangement, for example embodied together as a touch sensitive screen. The basic layout 1 is preferably divided into three parts or areas. Namely, the basic layout 1 comprises a general display area 2 , pressure sensitive or touch sensitive input keys 3 respectively provided with system and functional symbols, and a header line or bar 4 for identifying the respective active menu. The available menus, which can be selected and displayed individually or together in any conventionally known single window or multiple window format, include a main menu 10 (see FIG. 2) and at least two or more system menus 11 to 19 (see FIG. 2). The selected menu is respectively displayed on the general display area 2 of the basic layout 1 .
[0034] The main menu 10 displays the cabin status and the respective essential information or data regarding the various cabin systems so that a respective desired one of the cabin systems can be selected on a menu page of the main menu 10 , for example by simply touching the touch sensitive screen in an area corresponding to the display of the respective cabin system information or symbols, or by touching one of the touch input keys 3 that is associated with that system. Once a respective one of the cabin systems is selected, the respective associated system menu will be displayed on the general display area 2 of the basic layout 1 . The several system menus 11 to 19 are each respectively adapted for selecting, controlling and monitoring the functions of the respective associated cabin system. Thereby, the respective system menu is subordinate to the basic layout 1 and is displayed on the display area 2 when it is selected. Advantageously, the touch input keys 3 of the basic layout 1 are accessible and usable for an operator of the device regardless of the particular menu being displayed, i.e. for each display of a respective menu on the display area 2 .
[0035] As can also be seen in FIG. 1, the device further includes, incorporated in the basic layout 1 , an information key 5 , a help key or button 6 , a key or switch 7 for directly calling up the main menu regardless of the presently active state of the display area 2 , and a locking switch or key 8 for switching off and/or locking the display screen. Particularly, from any screen or menu or display, the information key 5 will provide context-sensitive further information for the operator of the apparatus, while the help key 6 will provide context-sensitive operating instructions and further help for operating the apparatus. For example, if the lighting system menu 12 is being displayed, the information key 5 would provide further detailed technical information, status information and the like regarding the various lighting system components, while the help key 6 would provide instructions or guidance as to the appropriate lighting selections and how to enter the desired lighting selections in the context of the lighting system menu 12 .
[0036] A scroll bar 9 is arranged above the keys 3 for the system and function symbols, whereby this scroll bar 9 shows an operator of the device that further menu sets are available. Preferably, the length of the elements of the scroll bar 9 approximately indicate the number of the subsequent menu sets. By operating the scroll bar, the successive available menu sets can be scrolled through, for example by scrolling the respective associated virtual labels or indications of the system or functional symbols indicated on the respective touch sensitive keys 3 . This is achieved, for example, by touching the scrolling arrow keys at the two ends of the strip of touch sensitive input keys 3 .
[0037] The menu structure represented in FIG. 2 shows the main menu 10 and several subordinate system menus 11 to 19 . The main menu key 7 for calling up the main menu, the system and function symbol keys 3 and the header line 4 of the basic layout 1 will be maintained on the basic layout 1 during and regardless of the call-up and display of any selected one of the several menus in the display area 2 . This is schematically indicated in that these elements are consistently shown in each one of the illustrated menus 11 to 19 . The main menu 10 is conceptually arranged between the basic layout 1 and the several system menus 11 to 19 , whereby any desired one of the system menus 11 to 19 can be selected and called up by an operator by manually touching the touch input keys 3 provided with the corresponding system and function symbols, or simply by touching the depiction of a corresponding system icon or symbol on the active main menu 10 being displayed on the touch sensitive general display area 2 of the basic layout 1 . As an alternative, the system menus 11 to 19 can be automatically successively called up and displayed in the display area 2 of the basic layout 1 , for example according to a prescribed succession plan or display sequence.
[0038] The linkages between the several system menus and the main menu are illustrated by corresponding arrows in FIG. 2. For example, from any system screen being displayed in the display area 2 of the basic layout 1 , the operator can return directly to the main menu 10 by pressing the main menu key 7 , also called the cabin status key 7 . Similarly, from any displayed menu, the operator can directly select a different desired system menu by pressing the corresponding touch input key 3 labeled with the appropriate corresponding system symbol or label. The scroll arrow touch input keys will, for example, scroll to the next successive or the previous system menu. In any event, once the selected main menu or system menu is displayed on the display area 2 of the basic layout 1 , the touch sensitive display screen becomes active with the appropriate touch sensitive input areas associated with the respective displayed menu. Thereby, the operator can select or control desired operating conditions of the respective displayed cabin system associated with the selected one of the system menus 11 to 19 by simply touching the appropriate corresponding function symbols being displayed on the associated menu on the display area 2 of the basic layout 1 .
[0039] Further details of the individual menus respectively shown in FIGS. 4 to 10 will be discussed below. In the context of the following discussion, several advantages of the invention will become apparent. The invention allows a reduction of the number of individual or separate operating devices. Namely, a single operating device is provided for monitoring and controlling all of the pertinent cabin systems. This in turn leads to a weight and cost reduction, savings with regard to the costs and effort needed for installation and cable connections, and makes simplified networking of the device possible. The inventive apparatus fulfills the specifications and other requirements for the control and monitoring of aircraft cabin systems especially in the newest high capacity aircraft, for example in connection with a complex lighting control or climate control, as well as providing an open interface for server applications and software download capabilities. The inventive apparatus can be readily adapted to accommodate the requirements of various customers of the aircraft manufacturer, i.e. the various airlines purchasing the aircraft. This is especially true because essentially all of the adaptations can be achieved simply by changes of the software and/or parameters in the cabin allocation or assignment module. An adaptation of the hardware (devices or accessories) is no longer necessary. All expansions and provision of new functions can be achieved simply by updating the software and/or the parameters in the cabin allocation or assignment module. It is therefore also possible that each customer airline can carry through its own individual company identity with special functions, options, displays, logos, messages, color schemes, or the like.
[0040] The simple schematic view of FIG. 3 represents the appearance of the overall apparatus or device during booting up of the overall system software, as shown with a so-called progress bar showing the progress of the boot-up procedure, for example. Note that the liquid crystal display screen is otherwise blank or empty. This demonstrates the preferred embodiment in which the entire user interface is embodied as a versatile, adaptable touch sensitive display screen, on which all of the touch input keys, display areas and the like are virtually generated and displayed as necessary for the particular situation. None of the input keys needs to be a permanent hard-wired element. After completion of the boot-up process, preferably the main menu 10 shown in FIG. 4 will be displayed on the general display area 2 of the basic layout 1 .
[0041] As shown in FIG. 4, the main menu 10 provides a general overview of the overall cabin status and includes the essential information or data regarding the various cabin systems to allow the desired pertinent cabin system to be selected. For example, the main menu 10 shows the cabin status of five different cabin systems relating to the system menus 11 to 15 , namely for the cabin audio system 11 , the cabin lighting system 12 , the aircraft doors 13 , the water supply and wastewater system 14 , and the temperature or air-conditioning system 17 . These several systems are respectively displayed with a corresponding graphical display of the relevant aspects of the cabin layout on the display area 2 , and from there the respective corresponding system menus can be directly selected and called-up by means of the touch sensitive screen technology, namely by simply touching the area of the display screen 2 on which the selected system image is displayed.
[0042] The system menu 11 shown in FIG. 5 is for controlling and monitoring the aircraft cabin audio system, namely with respect to selecting and playing previously recorded announcements as well as adjusting or selecting the on-board music channel. In this context, selection of the music channel and the volume is carried out by means of the respective corresponding +/− keys 111 in a virtual keyboard grouping on the left side of the system menu 11 . The currently existing status of these adjustments, i.e. the actually selected music channel and volume, is respectively indicated in corresponding display fields, namely a channel indicator 113 and a volume indicator 114 within a graphical aircraft symbol 112 .
[0043] On the other hand, passenger information and instruction announcements can be selected in a virtual display and keypad screen on the right side of the system menu 11 , for example through selection or input of the corresponding associated number of the announcement via the numerical key pad 115 . Then, by pressing the enter key 116 , the presently entered announcement number may be confirmed and selected, while on the other hand the clear key 117 may be touched in order to erase or clear the entered number. The arrow keys 118 can be used to scroll through the available recorded announcements in order to find one or more desired announcements in a targeted manner, to be queued in a view window or memo window 120 . The start key 119 can then be used to play the next selected announcement, while the clear key 117 can be used to clear the preselection. The “start-all” key 119 A can be touched to begin a sequential playing of all of the selected or stored announcements, while the list or sequence of stored announcements to be played is indicated in the memo window 120 , and the number of the currently playing announcement is displayed in the indicator field 120 A above the memo window 120 . In order to interrupt the playing of the announcement or announcements, a stop key is also provided.
[0044] Additional functions pertinent to the audio system can also be displayed and selected via virtual displays and keys, for example to adjust the PA level, to reset the call buttons, to inhibit call chimes, or the like. This is merely an example demonstration of various different functions and features that can be displayed and selected based on the needs of the individual application, simply by appropriate program adjustments.
[0045] The system menu 12 shown in FIG. 6 controls the cabin lighting system in the aircraft cabin. For example, this cabin lighting system can include separate lighting arrangements for the door entry zones, separate cabin zones, and/or individual independent partitioned areas, spaces or cabins within the aircraft, which may all be individually controlled and monitored from the system menu 12 . In this regard, the system menu 12 includes several sets or groups of touch input keys 121 , 122 , 123 and 124 , which each allow selection or adjustment of the desired lighting brightness level in respective different cabin areas. Preferably, in the cabin entry zones, any desired one of three brightness steps, namely bright or full illumination, dimming stage 1 , and dimming stage 2 can be selected. The current, actually selected lighting adjustments are displayed in a graphical aircraft symbol 125 , which is advantageously divided into the various lighting zones. Various other display features and/or input keys can be provided on the screen display of this system menu 12 , as needed for any particular application. For example, a fine-tuned brightness or dimness adjustment is possible by selecting a particular percentage of the maximum full brightness with corresponding arrow scroll keys. The functions of the other exemplary keys shown in FIG. 6 are self-explanatory in the context of aircraft cabin lighting systems.
[0046] [0046]FIG. 7 shows a system menu 13 , which shows the actual present status of all cabin doors and hatches. For example, a graphical aircraft symbol 131 includes a clearly visible graphical indication 131 A of each door, emergency exit hatch, emergency slide, and the like, as well as the respective status thereof. For example, the display or status indication can provide information whether each respective door or hatch is closed or open, pressure-tight or not pressure-tight, locked or unlocked, etc.
[0047] The system menu 14 shown in FIG. 8 is associated with the water supply and wastewater systems of the aircraft. The system menu 14 includes, on the right side, a graphical aircraft symbol 141 , in which the location of each galley and each restroom or toilet is indicated. It is also indicated whether the galley or restroom is properly functional and active, or inactive due to a malfunction or error. In the upper part of the menu 14 , graphical images of supply water and wastewater tanks 142 also show the current actual existing water level or volume of water in each tank. Arrows or other indicators can mark prescribed volume values or warning levels or the like. Furthermore, a display screen 143 allows the current actual existing status values of the above mentioned components to be displayed. Input and selection keys can also be provided to allow an operator to control these components.
[0048] Accordingly to FIG. 9, the inventive apparatus further provides a system menu 15 , which displays status values of various cabin systems, and which is preferably called-up before take-off of any flight. An automatic call-up and display of this menu 15 is also advantageous during any flight phase, if the flight crew of the aircraft requires information or status data regarding any of the individual systems. For example, the display can include display fields for status information regarding the cabin intercommunication data system (CIDS), the ice or freeze protection devices, or the electric power supply system. By touching a selection key associated with each respective display field, the operator can then obtain detailed status information regarding the particular selected system.
[0049] The system menu 16 shown in FIG. 10 is provided to allow programming of the cabin systems, for example with regard to various parameters in different cabin zones. In the illustrated example, a graphical aircraft symbol 161 shows the several cabin zones, for example in respective seat row ranges or areas, and various touch input key fields 162 , 163 and 164 for inputting programming commands for the associated functions in relation to the respective cabin zones or areas. For example, the display and input key field 164 allows a programming of the cabin areas in which smoking will be allowed and those cabin areas in which smoking will not be allowed, e.g. by illuminating the corresponding appropriate smoking or non-smoking indicators in the respective associated cabin areas.
[0050] Although the invention has been described with reference to specific example embodiments, it will be appreciated that it is intended to cover all modifications and equivalents within the scope of the appended claims. It should also be understood that the present disclosure includes all possible combinations of any individual features recited in any of the appended claims | A method of monitoring and controlling a plurality of aircraft cabin systems using a user interface having a touch sensitive display and a plurality of input keys corresponding to the plurality of aircraft cabin systems. The method includes activating one of the input keys corresponding to a first system of the plurality of aircraft cabin systems to display a first system graphical menu having status information and operating functions of the first system, and touching a touch sensitive input area of the first system graphical menu to perform at least one of selection and control of the operating functions of the first system. Another one of the input keys corresponding to a second system of the plurality of aircraft cabin systems can be activated to display a second system graphical menu having status information and operating functions of the second system, and a touch sensitive input area of the second system graphical menu can be touched to perform at least one of selection and control of the operating functions of the second system. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a divisional of U.S. Application Ser. No. 13/274,947, filed on Oct. 17, 2011, which is a non-provisional of U.S. Provisional Application No. 61/500,914, filed on Jun. 24, 2011, both of which is hereby incorporated herein by reference in its entirety for all purposes.
BACKGROUND
[0002] Offshore oil and gas operations often utilize a wellhead housing supported on the ocean floor and a blowout preventer stack secured to the wellhead housing's upper end. A blowout preventer stack is an assemblage of blowout preventers and valves used to control well bore pressure. The upper end of the blowout preventer stack has an end connection or riser adapter (often referred to as a lower marine riser packer or LMRP) that allows the blowout preventer stack to be connected to a series of pipes, known as riser, riser string, or riser pipe. Each segment of the riser string is connected in end-to-end relationship, allowing the riser string to extend upwardly to the drilling rig or drilling platform positioned over the wellhead housing.
[0003] The riser string is supported at the ocean surface by the drilling rig. This support takes the form of a hydraulic tensioning system and telescoping (slip) joint that connect to the upper end of the riser string and maintain tension on the riser string. The telescoping joint is composed of a pair of concentric pipes, known as an inner and outer barrel, that are axially telescoping within each other. The lower end of the outer barrel connects to the upper end of the aforementioned riser string. The hydraulic tensioning system connects to a tension ring secured on the exterior of the outer barrel of the telescoping joint and thereby applies tension to the riser string. The upper end of the inner barrel of the telescoping joint is connected to the drilling platform. The axial telescoping of the inner barrel within the outer barrel of the telescoping joint compensates for relative elevation changes between the rig and wellhead housing as the rig moves up or down in response to the ocean waves.
[0004] According to conventional practice, various auxiliary fluid lines are coupled to the exterior of the riser tube. Exemplary auxiliary fluid lines include choke, kill, booster, and hydraulic fluid lines. Choke and kill lines typically extend from the drilling rig to the wellhead to provide fluid communication for well control and circulation. The choke line is in fluid communication with the borehole at the wellhead and may bypass the riser to vent gases or other formation fluids directly to the surface. According to conventional practice, a surface-mounted choke valve is connected to the terminal end of the choke conduit line. The downhole back pressure can be maintained substantially in equilibrium with the hydrostatic pressure of the column of drilling fluid in the riser annulus by adjusting the discharge rate through the choke valve.
[0005] The kill line is primarily used to control the density of the drilling mud. One method of controlling the density of the drilling mud is by the injection of relatively lighter drilling fluid through the kill line into the bottom of the riser to decrease the density of the drilling mud in the riser. On the other hand, if it is desired to increase mud density in the riser, a heavier drilling mud is injected through the kill line.
[0006] The booster line allows additional mud to be pumped to a desired location so as to increase fluid velocity above that point and thereby improve the conveyance of drill cuttings to the surface. The booster line can also be used to modify the density of the mud in the annulus. By pumping lighter or heavier mud through the booster line, the average mud density above the booster connection point can be varied. While the auxiliary lines provide pressure control means to supplement the hydrostatic control resulting from the fluid column in the riser, the riser tube itself provides the primary fluid conduit to the surface.
[0007] A hose or other fluid line connection to each auxiliary fluid line coupled to the exterior of the riser tube is provided at the telescoping joint via a pipe or equivalent fluid channel. The pipe is often curved or U-shaped, and is accordingly termed a “gooseneck” conduit. In the course of drilling operations, a gooseneck conduit may be detached from the riser, for example, for maintenance or to permit the raising of the riser through the drilling floor, and reattached to the riser to provide access to the auxiliary fluid lines. The gooseneck conduits are typically coupled to the auxiliary fluid lines via threaded connections.
SUMMARY
[0008] A gooseneck conduit system for use with a telescoping joint of a subsea riser is disclosed herein. In one embodiment, a riser telescoping joint includes a tube and a gooseneck conduit assembly affixed to the tube. The gooseneck conduit assembly includes a gooseneck conduit extending radially from the tube, and a tenon projecting from a rear face of the gooseneck conduit. The width of the tenon increases with distance from the rear face. The riser telescoping joint also includes a mortise channel extending lengthwise along the tube. The mortise channel interlocks with the tenon to laterally secure the gooseneck conduit assembly to the tube.
[0009] In another embodiment, a gooseneck conduit unit includes a plate, a gooseneck conduit, and a bumper. The gooseneck conduit is removably mounted to the plate. The bumper is coupled to a rear face of the gooseneck conduit. The bumper includes a tenon that guides the gooseneck conduit unit into position on a telescoping joint.
[0010] In a further embodiment, a system includes a telescoping joint. The telescoping joint includes an alignment ring and a gooseneck conduit assembly. The alignment ring is circumferentially coupled to a tube of the telescoping joint. The alignment ring includes a longitudinal mortise channel. The gooseneck conduit assembly is coupled to the alignment ring. The gooseneck conduit assembly includes a gooseneck conduit and a tenon. The tenon slidingly engages sides of the mortise channel to secure the gooseneck conduit assembly to the alignment ring.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011] For a detailed description of exemplary embodiments of the invention, reference will now be made to the accompanying drawings in which:
[0012] FIGS. 1A-1B show a drilling system including a gooseneck conduit system in accordance with various embodiments;
[0013] FIG. 2 shows a telescoping joint in accordance with various embodiments;
[0014] FIG. 3 shows a top view of a plurality of gooseneck conduit assemblies in accordance with various embodiments;
[0015] FIG. 4 shows an elevation view of a support collar and gooseneck conduit assemblies in accordance with various embodiments;
[0016] FIG. 5 shows a perspective view of a support collar and gooseneck conduit assemblies in accordance with various embodiments; and
[0017] FIG. 6 shows a cross sectional view of a support collar and gooseneck assemblies in accordance with various embodiments.
NOTATION AND NOMENCLATURE
[0018] Certain terms are used throughout the following description and claims to refer to particular system components. As one skilled in the art will appreciate, companies may refer to a component by different names. This document does not intend to distinguish between components that differ in name but not function. In the following discussion and in the claims, the terms “including” and “comprising” are used in an open-ended fashion, and thus should be interpreted to mean “including, but not limited to . . . .” Also, the term “couple” or “couples” is intended to mean either an indirect or direct connection. Thus, if a first device couples to a second device, that connection may be through a direct connection, or through an indirect connection via other devices and connections.
DETAILED DESCRIPTION
[0019] The following discussion is directed to various embodiments of the invention. The drawing figures are not necessarily to scale. Certain features of the embodiments may be shown exaggerated in scale or in somewhat schematic form and some details of conventional elements may not be shown in the interest of clarity and conciseness. Although one or more of these embodiments may be preferred, the embodiments disclosed should not be interpreted, or otherwise used, as limiting the scope of the disclosure, including the claims. It is to be fully recognized that the different teachings of the embodiments discussed below may be employed separately or in any suitable combination to produce desired results. In addition, one skilled in the art will understand that the following description has broad application, and the discussion of any embodiment is meant only to be exemplary of that embodiment, and not intended to intimate that the scope of the disclosure, including the claims, is limited to that embodiment.
[0020] The size and weight of the gooseneck conduits, and the location of the attachment points of the conduits to the telescoping joint and the auxiliary fluid lines, makes installation and/or retrieval of the conduits a labor-intensive process. Consequently, gooseneck conduit handling operations can be time consuming and costly. Embodiments of the present disclosure include a gooseneck conduit system that reduces handling time and enhances operational safety. Embodiments of the conduit system disclosed herein can provide simultaneous connection of gooseneck conduits to a plurality of auxiliary fluid lines with no requirement for manual handling or connection operations. Embodiments include hydraulically and/or mechanically operated locking mechanisms that secure the conduit system to the telescoping joint and the auxiliary fluid lines. The conduit system may be hoisted into position on the telescoping joint, and attached to the telescoping joint and the auxiliary fluid lines via the provided locking mechanisms. Thus, embodiments allow gooseneck conduits to be quickly and safely attached to and/or removed from the telescoping joint.
[0021] FIGS. 1A-1B show a drilling system 100 in accordance with various embodiments. The drilling system 100 includes a drilling rig 126 with a riser string 122 and blowout preventer stack 112 used in oil and gas drilling operations connected to a wellhead housing 110 . The wellhead housing 110 is disposed on the ocean floor with blowout preventer stack 112 connected thereto by hydraulic connector 114 . The blowout preventer stack 112 includes multiple blowout preventers 116 and kill and choke valves 118 in a vertical arrangement to control well bore pressure in a manner known to those of skill in the art. Disposed on the upper end of blowout preventer stack 112 is riser adapter 120 to allow connection of the riser string 122 to the blowout preventer stack 112 . The riser string 122 is composed of multiple sections of pipe or riser joints 124 connected end to end and extending upwardly to drilling rig 126 .
[0022] Drilling rig 126 further includes moon pool 128 having telescoping joint 130 disposed therein. Telescoping joint 130 includes inner barrel 132 which telescopes inside outer barrel 134 to allow relative motion between drilling rig 126 and wellhead housing 110 . Dual packer 135 is disposed at the upper end of outer barrel 134 and seals against the exterior of inner barrel 132 . Landing tool adapter joint 136 is connected between the upper end of riser string 122 and outer barrel 134 of telescoping joint 130 . Tension ring 138 is secured on the exterior of outer barrel 134 and connected by tension lines 140 to a hydraulic tensioning system as known to those skilled in the art. This arrangement allows tension to be applied by the hydraulic tensioning system to tension ring 138 and telescoping joint 130 . The tension is transmitted through landing tool adapter joint 136 to riser string 122 to support the riser string 122 . The upper end of inner barrel 132 is terminated by flex joint 142 and diverter 144 connecting to gimbal 146 and rotary table spider 148 .
[0023] A support collar 150 is coupled to the telescoping joint 130 , and the auxiliary fluid lines 152 are terminated at seal subs retained by the support collar 150 . One or more gooseneck conduit assemblies 154 are coupled to the support collar 150 and to the auxiliary fluid lines 152 via the seal subs retained by the support collar 150 . Each conduit assembly 154 is a conduit unit that includes one or more gooseneck conduits 156 . A hose 158 or other fluid line is connected to each gooseneck conduit 156 for transfer of fluid between the gooseneck conduit 156 and the drilling rig 126 . In some embodiments, the connections between the hoses 158 and/or other rig fluid lines and the gooseneck conduits 156 are made on the rig floor, and thereafter the gooseneck conduit assembly 154 is lowered onto the telescoping joint 130 .
[0024] The gooseneck conduit assembly 154 includes locking mechanisms that secure the conduit assembly 154 to the telescoping joint 130 . The conduit assembly 154 can be lowered onto the support collar 150 using a crane or hoist. In some embodiments, the conduit assembly 154 can be connected to hydraulic lines that actuate the locking mechanisms. Thus, embodiments allow the gooseneck conduits 156 to be quickly and safely fixed to and/or removed from the telescoping joint 130 while reducing the manual effort required to install and/or remove the gooseneck conduits 156 .
[0025] FIG. 2 shows the telescoping joint 130 in accordance with various embodiments. The auxiliary fluid lines 152 are secured to the telescoping joint 130 . The uphole end of each auxiliary fluid line 152 is coupled to a seal sub 206 at the support collar 150 . The support collar 150 is coupled to and radially extends from the telescoping joint 130 . In some embodiments, the support collar 150 includes multiple connected sections (e.g., connected by bolts) that join to encircle the telescoping joint 130 .
[0026] The gooseneck conduit assembly 154 includes one or more locking mechanisms, and a plurality of gooseneck conduits 156 . As the gooseneck conduit assembly 154 is positioned on the support collar 150 , each gooseneck conduit 156 engages a seal sub 206 and is coupled to an auxiliary fluid line 152 . The locking mechanisms secure the gooseneck conduit assembly 154 to the support collar 150 , and secure each gooseneck conduit 156 to a corresponding auxiliary fluid line 152 . In some embodiments, the locking mechanisms are hydraulically operated. In other embodiments, the locking mechanisms are mechanically operated. The locking mechanisms may be either hydraulically or mechanically operated in some embodiments. The gooseneck conduits 156 may include swivel flanges 208 for connecting the conduits 156 to fluid lines 158 .
[0027] FIG. 3 shows a top view of a plurality of gooseneck conduit assemblies 154 in accordance with various embodiments. Each gooseneck conduit assembly 154 includes one or more gooseneck conduits 156 . Each gooseneck conduit assembly 154 includes a top plate 302 and fasteners 312 that connect the top plate 302 to underlying structures explained below. The gooseneck conduit assembly 154 includes a projection or tenon 306 for aligning and locking the gooseneck conduit assembly 154 to the telescoping joint 130 . Some embodiments of the gooseneck conduit assembly 154 include a tenon 306 coupled to each gooseneck conduit 156 . In some embodiments, the tenon 306 may be trapezoidal, or fan-shaped to form a dove-tail tenon. Other embodiments may include a differently shaped tenon 306 . The tenon 306 may be formed by a bumper attached to the rear face 318 of the gooseneck conduit 156 , with the bumper, and thus the tenon 306 , extending along the length of the rear face 318 . In some embodiments, the tenon 306 may be made of bronze or another suitable material. In some embodiments, the tenon 306 may be part of the gooseneck conduit 156 .
[0028] An alignment guidance ring 316 is circumferentially attached to the telescoping joint 130 . The alignment guidance ring 316 includes channel mortises 304 that receive, guide the gooseneck conduits 156 into alignment with the seal subs 206 , and retain the tenons 306 as the gooseneck conduit assembly 154 is lowered onto the telescoping joint 130 . Consequently, the mortises 304 are shaped to mate with and slidingly engage the tenons 306 (i.e., a trapezoids, dove-tails, etc). The channel mortises 304 may narrow with proximity to the support collar 150 (with proximity to the bottom of the alignment ring 316 ). Similarly, the tenons 306 may narrow with distance from the top plate 302 (with proximity to the bottom of the rear face 318 of the gooseneck conduit 156 ). The tenons 306 and mortises 304 are dimensioned to securely interlock.
[0029] The gooseneck conduit assembly 154 includes locking mechanisms that secure the gooseneck conduit assembly 154 to the telescoping joint 130 . Embodiments may include one or more locking mechanisms that are mechanically or hydraulically actuated. For example, embodiments may include a primary and a secondary locking mechanism. Hydraulic secondary backup locks 308 are included on some embodiments of the gooseneck conduit assembly 154 . The hydraulic secondary locks include a hydraulic cylinder that operates the lock. Other embodiments include mechanical secondary backup locks 310 . In some embodiments, the secondary backup locks secure the primary locking mechanisms into position. Lock state indicators 314 show the state of conduit assembly locks. For example, extended indicators 314 indicate a locked state, and retracted indicators 314 indicate an unlocked state.
[0030] FIG. 4 shows an elevation view of the support collar 150 and gooseneck conduit assemblies 154 in accordance with various embodiments. The gooseneck conduit assembly 154 A includes two gooseneck conduits 156 , and is unlocked and separated from the telescoping joint 130 , and positioned above the support collar 150 . The gooseneck conduit assembly 154 B includes three gooseneck conduits 156 , and is secured to the telescoping joint 130 and associated seal subs 206 . Each gooseneck conduit 156 is replaceably fastened to a lower support plate 404 by bolts or other attachment devices. The upper support plate 302 is attached to the lower support plate 404 . The support collar 150 retains the seal subs 206 via clamps 412 attached to the support collar 150 by bolts or other fastening devices.
[0031] The alignment and guidance ring 316 is secured to the telescoping joint 130 . The alignment and guidance ring 316 may be formed from a plurality of ring sections joined by bolts or other fastening devices. The alignment and guidance ring 316 includes a locking channel 406 . The gooseneck conduit assembly 154 B rests on surface 502 ( FIG. 5 ) of the alignment and guidance ring 316 , and as discussed above, the tenons 306 interlock with the mortises 304 to laterally secure the gooseneck conduit assembly 154 B. The locking member 408 extends from the gooseneck conduit assembly 154 B into the locking channel 406 to prevent movement of the gooseneck conduit assembly 154 B upward along the telescoping joint 130 .
[0032] FIG. 5 shows a perspective view of the support collar 150 and the gooseneck conduit assemblies 154 as arranged in FIG. 4 .
[0033] FIG. 6 shows a cross-sectional view of the support collar 150 and gooseneck conduit assemblies 154 as arranged in FIG. 4 . Embodiments of the gooseneck conduits assemblies 154 may include any combination of hydraulic and mechanical primary and secondary locks. The gooseneck conduit assembly 154 B includes a hydraulic primary lock 618 and a hydraulic secondary lock 308 . The components of the hydraulic primary lock 618 are disposed between the upper and lower support plates 302 and 404 . The hydraulic primary lock 618 includes a hydraulic cylinder 612 coupled to the locking member 408 for extension and retraction of the locking member 408 .
[0034] The components of the hydraulic secondary lock 308 are secured to the upper plate 302 by hydraulic cylinder support plate 606 . The hydraulic secondary lock 308 includes a hydraulic cylinder 602 coupled to a locking pin 604 for extension and retraction of the locking pin 604 . When the locking member 408 has been extended, extension of the locking pin 604 secures the locking member 408 in the extended position. In some embodiments, the locking member 408 includes a passage 608 . The locking pin 604 extends into the passage 608 to secure the locking member 408 in the extended position.
[0035] The gooseneck conduit assembly 154 A includes a hydraulic primary lock 618 and a mechanical secondary lock 310 . As described above, the components of the hydraulic primary lock 618 , including the hydraulic cylinder 612 , and the locking member 408 , are disposed between the upper and lower support plates 302 and 404 . In some embodiments, the locking member 408 may be retracted by mechanical rather than hydraulic means. For example, force may be applied to the state indicator 314 to retract the locking member 408 from the locking channel 406 . The mechanical secondary lock 310 comprises an opening 624 that allows a bolt or retention pin to be inserted into the passage 608 of the locking member 408 when the locking member 408 is extended.
[0036] An upper split retainer 626 and a lower split retainer 622 are attached to the support collar 150 to reduce support collar 150 radial loading. The upper split retainer 626 is bolted to the upper side of the support collar 150 , and the lower split retainer 622 is bolted to the lower side of the support collar 150 . Each split retainer 626 , 622 comprises two sections. The two sections of each retainer 626 , 622 abut at a position 90° from the location where the support collar sections are joined. The upper split retainer 626 includes a tapered surface 628 on the inside diameter that retains and positions the support collar 150 on the telescoping joint 130 . The support collar 150 also includes a key structure (not shown) for aligning the support collar 150 with a keying structure of the telescoping joint and preventing rotation of the support collar 150 about the telescoping joint 130 .
[0037] Each gooseneck conduit 156 includes an arcing passage 614 extending through the gooseneck conduit 156 for passing fluid between the auxiliary fluid line 152 and the hose 158 . The gooseneck conduit assembly 156 may be formed by a casting process, and the thickness of material between the passage 614 and the exterior surface of the gooseneck conduit 156 may exceed the diameter of the passage 614 (by 2-3 or more times in some embodiments) thereby enhancing the strength and service life of the gooseneck conduit 156 . The gooseneck conduit 156 includes a socket 630 that sealingly mates with the seal sub 206 to couple the gooseneck conduit 156 to the auxiliary fluid line 152 . The socket 630 includes grooves 616 for holding a sealing device, such as an O-ring, that seals the connection between the gooseneck conduit 156 and the sealing sub 206 .
[0038] The above discussion is meant to be illustrative of the principles and various embodiments of the present invention. Numerous variations and modifications will become apparent to those skilled in the art once the above disclosure is fully appreciated. It is intended that the following claims be interpreted to embrace all such variations and modifications. | A gooseneck conduit system for use with a telescoping joint of a subsea riser. In one embodiment, a riser telescoping joint includes a tube and a gooseneck conduit assembly affixed to the tube. The gooseneck conduit assembly includes a gooseneck conduit extending radially from the tube, and a tenon projecting from a rear face of the gooseneck conduit. The width of the tenon increases with distance from the rear face. The riser telescoping joint also includes a mortise channel extending along the length of the tube. The mortise channel is interlocks with the tenon and laterally secures the gooseneck conduit assembly to the tube. | 4 |
BACKGROUND
1. Field of the Invention
The present invention is concerned with a novel process for the manufacture of quinone derivatives, especially of compounds of the vitamin K series and of ubiquinones. The invention is also concerned with novel starting materials and intermediates in this process.
2. Description
The hitherto known processes for the manufacture of such compounds normally start from hydroquinones or monoacylated hydroquinones and are therefore technically unsatisfactory, since a relatively large number of reaction steps must be carried out. Technically practicable processes starting from, for example, menadione itself or a readily accessible derivative thereof are hitherto unknown. This gap has now been closed by means of the process in accordance with the invention, since this permits vitamins of the K series as well as ubiquinones to be manufactured in one or two steps starting from readily accessible starting materials. Moreover, the process in accordance with the invention is of particular interest, since, in contrast to many previously known processes, it terminated with practically complete retention of the configuration of the double bond(s) in the side-chain.
SUMMARY OF THE INVENTION
The present invention concerns a process for preparing quinone derivatives. The inventive process comprises reacting a compound of the formula: ##STR4## wherein R 1 and R 2 each are methoxy or taken together are --CH═CH--CH═CH--,
with a compound of the formula ##STR5## wherein R 3 is a leaving group and R 4 is 3,7,11-trimethyldodecane or a group of the formula ##STR6## in which n is an integer from 0 to 12, and, if desired, converting a thus-obtained compound of the formula ##STR7## wherein R 1 , R 2 and R 4 have the significance given above, into a compound of the formula ##STR8## wherein R 1 , R 2 and R 4 have the significance given above.
DETAILED DESCRIPTION OF THE INVENTION
The present invention is concerned with a novel process for the manufacture of quinone derivatives, especially of compounds of the vitamin K series and of ubiquinones. The invention is also concerned with novel starting materials and intermediates in this process. More particularly, the present invention concerns a process for producing an intermediate of the formula ##STR9## wherein R 1 and R 2 each are methoxy or when taken together are --CH═CH--CH═CH, and R 4 is 3,7,11-trimethyl-dodecane or a group of the formula ##STR10## in which n is an integer from 0 to 12.
In accordance with the present invention, a compound of the formula ##STR11## wherein R 1 and R 2 are as above, is reacted with a compound of the formula ##STR12## wherein R 3 is a leaving group and R 4 is as above, thereby to produce compound IV.
If desired compound IV can be converted to a compound of the formula ##STR13## wherein R 1 , R 2 , and R 4 are as above.
Formula V represents compounds of the vitamin K series, such as K 1 , K 2 (5), K 2 (10) etc. or ubiquinones, which are known compounds with known utility.
As used herein, the term "leaving group" denotes any conventional leaving groups which are commonly used in chemistry. More particularly, "leaving group" includes especially halogen such as fluorine, chlorine, bromine and iodine, with bromine and chlorine being preferred, or groups such as the mesyloxy group, the tosyloxy group, the acetate group and the like.
Alkali metal denotes lithium, sodium, potassium and rubidium.
In the pictorial representations of the compounds, the notation " " signifies that the corresponding residue is situated above the plane of the molecule.
Unless otherwise indicated, all pictorial representations of appropriate compounds include cis/trans mixtures as well as corresponding cis and trans compounds.
The process in accordance with the invention permits the manufacture of trans/cis mixtures of the compounds of formulae IV and V, as well as the practically pure (E)- or (Z)-isomers depending on the configuration of the starting materials of formula II. Thus, for example, when a compound of formula II is used in the pure (E)-form, there can be obtained the corresponding compounds of formulae IV and V in practically pure (E)-form. When a compound of formula II is used in a cis/trans mixture, there can be obtained the corresponding compounds of formulae IV and V in cis/trans form.
The reaction of a compound of formula I with a compound of formula II can be carried out in an inert organic solvent which is inert under the reaction conditions and in the presence of a strong base. As solvents there come into consideration not only polar solvents but also apolar solvents. Apolar aprotic solvents such as, for example, aliphatic or aromatic hydrocarbons such as hexane, benzene, toluene and the like are preferred. The preferred polar protic solvent is tert.butanol. Mixtures of these solvents are also preferred. As strong bases there come into consideration in the scope of the present invention especially organic bases such as, for example, amides such as alkali metal amides (Li, Na K) or lithium dialkylamides, alcoholates such as alkali metal tert.butylates or hydrides such as sodium hydride or potassium hydride and the like. The reaction can be carried out at a temperature of about -20° C. to about +30° C., preferably at about -5° C. to about +10° C. and especially at about 0° C. to +5° C.
The compounds of formula IV are novel and also form an object of the present invention.
The conversion of a compound of formula IV into a compound of formula V is a retro-Diels-Alder reaction and can accordingly be carried out in a manner known per se. The heating can be carried out in the absence or in the presence of an inert solvent, for example at a temperature of about room temperature (about 23° C.) to about 200° C. preferably at a temperature of about 70° C. to about 120° C.
The compounds of formula II which are used as starting materials are known and can be prepared in a known manner.
The compounds of formula I which are used as starting materials in the process in accordance with the invention are novel and also form an object of the present invention. They can be prepared, for example, by reacting a quinone of the formula ##STR14## wherein R 1 and R 2 have the significance given above, with cyclopentadiene. This reaction can be carried out in an inert organic solvent and preferably at a temperature of about 0° C. to about 40° C., especially at room temperature. An organic acid such as, for example, acetic acid, propionic acid and the like is preferably used as the solvent.
The following examples illustrate the manufacture of the compounds provided by the invention and the preparation of starting materials. Unless otherwise stated, percentages and ratios relating to solvent mixtures are expressed in volume, purity data determined by gas chromatography are expressed in area %, and the remaining percentages and ratios are expressed in weight. Temperatures are in degrees Celsius (°C.), normal pressure is about 1 atmosphere, and room temperature is about 23° C. Unless indicated otherwise, the examples were carried out as written.
EXAMPLE 1
50 ml of tert.butanol/toluene (4:1) and 1.65 g (42 mmol) of potassium were placed under argon in a sulphonation flask equipped with a stirrer, a reflux condenser and argon gasification and heated at reflux for 1 hour. Thereupon, the mixture was cooled to 0° C. and treated with 5 g (21 mmol) of 1,4,4aα,9a-tetrahydro-9aα-methyl-1α,4α-methanoanthraquinone. The red solution obtained was stirred at 0° C. for a further 5 minutes. 8.7 g (1.15 eq.) of trans-phytyl bromide in 10 ml of tert.butanol/toluene (4:1) were subsequently added dropwise during about 15 minutes and the mixture was stirred at 0° C. for 1 hour. Thereupon, 15 ml of 3N HCl were added dropwise and the resulting yellow solution was stirred at room temperature for 0.5 hour. Thereupon, a 25% ammonia solution was added until the solution was orange. The solution was then concentrated on a rotary evaporator and extracted twice with hexane. The organic extracts were washed with saturated NaCl solution, dried over Na 2 SO 4 , filtered and concentrated. There were obtained 12.5 g of a brown oil which was chromatographed on a 400 g SiO 2 column with hexane/ethyl acetate (19:1). In this manner there were obtained 10.1 g of 1,4,4a,9a-tetrahydro-9aα-methyl-4aα-[3,7,11,15-tetramethyl-2-hexadecenyl]-1α,4α-methanoanthraquinone in the form of a yellow oil.
10.1 g (19.6 mmol) of the previously obtained yellow oil were dissolved in about 25 ml of toluene and heated at reflux under argon in the dark for 15 minutes. The mixture was then cooled and concentrated on a rotary evaporator. There were obtained 9 g of a yellow oil which was chromatographed on a 300 g SiO 2 column with hexane/ethyl acetate (19:1). There were thus obtained 8.1 g of trans-vitamin K 1 in the form of a yellow oil.
HPLC: ratio trans/cis=96.1:3,9.
The 1,4,4aα,9a-tetrahydro-9aα-methyl-1α,4α-methanoanthraquinone used as the starting material was prepared as follows:
103.6 g (0.6 mol) of menadione in 400 ml of acetic acid were placed in a flask. 126 ml (1.53 mol) of 1,3-cyclopentadiene were then added and the mixture was stirred at room temperature. All had dissolved after about 2.5 hours. After 4 days at room temperature the solution was concentrated on a rotary evaporator at 50° C., the residue was recrystallized at 0° C. from 280 ml of methanol, the crystals were filtered off and dried for 3 hours at 35° C. in a water-jet vacuum. There were obtained 121.6 g of 1,4,4aα,9a-tetrahydro-9aα-methyl-1α,4α-methanoanthraquinone with a melting point of 95°-97° C.
In a manner analogous to the foregoing, starting from 1.8 g (7.5 mmol) of 1,4,4aα,9a-tetrahydro-9aαmethyl-1α,4α-methanoanthraquinone and 3.5 g (1.3 eq.) of cis-phytyl bromide there were obtained 1.83 g of cis-vitamin K 1 in the form of a yellow oil. HPLC content: 99% cis.
EXAMPLE 2
40 ml of tert.butanol and 1.65 g (42 mmol) of potassium were added under nitrogen to a 200 ml sulphonation flask equipped with a stirrer, a reflux condenser and argon gasification and heated at reflux for 1.5 hours. Thereupon, the mixture was cooled to room temperature and treated with 10 ml of toluene. The mixture was then cooled to +3° C. by means of an ice-bath. 5 g (21 mmol) of 1,4,4aα,9a-tetrahydro-9aα-methyl-1α,4α-methanoanthraquinone (prepared in accordance with Example 1) were then added and the mixture was stirred at +3° C. for 5 minutes. Thereupon, 9.8 g (27.3 mmol) of trans-phytyl bromide in 10 ml of tert.butanol/toluene (4:1) were added dropwise within 20 minutes at about 5° C. and the mixture was stirred at about +3° C. for a further 0.5 to 1 hour. 15 ml (45 mmol) of 3N HCl were subsequently added. The mixture was then warmed to +25° C. with a warm water-bath and stirred intensively at room temperature for 0.75 hour. Thereupon, 25% ammonia solution was added dropwise until the colour of the solution changed from pale yellow to orange. The solution was then concentrated on a rotary evaporator at 25°-30° C. The residue was taken up twice in 300 ml of hexane, washed once with semi-saturated NaCl solution and once with saturated NaCl solution and subsequently dried over Na 2 SO 4 . There were obtained 12.9 g of a yellow oil.
This oil was subsequently dissolved in 25 ml of toluene and heated at reflux for 15 minutes under argon in the dark. The mixture was then cooled and concentrated on a rotary evaporator at 35° C. There were obtained 12.5 g of a yellow-red oil which was chromatographed on 430 g of SiO 2 with hexane/ethyl acetate (19:1). There were obtained 8.6 g of trans-vitamin K 1 in the form of a yellow oil. HPLC: ratio trans/cis=96.6:3.4.
In a manner analogous to the foregoing, with the use of trans/cis-phytyl bromide there was obtained trans/cis-vitamin K 1 . HPLC: ratio trans to cis=77 to 23.
EXAMPLE 3
In a manner analogous to Example 1 or 2, by reacting 1,4,4aα,9a-tetrahydro-9aα-methyl-1α,4α-methanoanthraquinone with
(a) trans-phytyl chloride there was obtained trans-vitamin K 1 .
HPLC: ratio trans to cis=98.3 to 1.7.
(b) with trans/cis-phytyl chloride there was obtained trans/cis-vitamin-K 1 .
HPLC: ratio trans to cis=75 to 25.
EXAMPLE 4
4.7 g (42 mmol) of potassium tert.butylate in 40 ml of tert.butanol/toluene (4:1) were placed in a sulphonation flask equipped with a stirrer, a reflux condenser and argon gasification. After cooling the mixture to 0° C. 5.0 g (21 mmol) of 1,4,4aα,9a-tetrahydro-9aα-methyl-1α,4α-methanoanthraquinone (prepared in accordance with Example 1) were added. The dark red mixture was subsequently stirred at 0° C. for a further 10 minutes. Thereupon, 3.4 g (22.8 mmol) of dimethylallyl bromide in 10 ml of tert.butanol/toluene (4:1) were added dropwise within 15 minutes and the mixture was stirred at 0° C. for a further 30 minutes. 20 ml of water were then added and the mixture was concentrated on a rotary evaporator. The residue was poured into 300 ml of semi-saturated NaCl solution, extracted with hexane, then washed with saturated NaCl solution, subsequently dried over Na 2 SO 4 and then concentrated. There were obtained 6.5 g of 1,4,4a,9a-tetrahydro-9aα-methyl-4aα-(3-methyl-2-butenyl)-1.alpha.,4α-methanoanthraquinone in the form of yellow crystals.
For the recrystallization, these crystals were dissolved in 20 ml of ethanol, the solution was cooled firstly to 0° C. and then to -20° C. The separated crystals were filtered off and washed with ice-cold ethanol. The crystals were subsequently dried for 1 hour at 40° C. in a water-jet vacuum. There were obtained 4.4 g of pale yellow crystals with a melting point of 105°-106° C.
4.4 g of the previously mentioned pale yellow crystals were dissolved in 20 ml of toluene and heated at reflux under argon for 15 minutes. The mixture was subsequently cooled and concentrated on a rotary evaporator. There were obtained 4.1 g of a yellow oil which was chromatographed on a 125 g SiO 2 column with hexane/ethyl acetate (19:1). In this manner there were obtained 3.5 g of vitamin K 2 (5) as a yellow oil. HPLC content: 99%.
EXAMPLE 5
The following compounds were manufactured in a manner analogous to Example 4 starting from 1,4,4aα,9a-tetrahydro-9aα-methyl-1α,4α-methanoanthraquinone:
By reaction with geranyl bromide the 4aα-[(E)-3,7-dimethyl-2,6-octadienyl]-1,4,4a,9a-tetrahydro-9aα-methyl-1α,4α-anthraquinone with a melting point of 68°-69° C., and therefrom vitamin K 2 (10) as yellow crystals with a melting point of 55°-56° C.; HPLC content: 99.4%,
by reaction with farnesyl bromide with 1,4,4a9a-tetrahydro-9aα-methyl-4aα-[(all-E)-3,7,11-trimethyl-2,6,10-dodecatrienyl]-1α,4α-anthraquinone, and therefrom vitamin K 2 (15) as a yellow oil. HPLC content: 97.5%.
by reaction with geranylgeranyl bromide the 1,4,4a,9a-tetrahydro-9aα-methyl-4aα-[(all-E)-3,7,11,15-tetramethyl-2,6,10,14-hexadecatetraenyl]-1α,4α-methanoanthraquinone, and therefrom vitamin K 2 (20) in the form of yellow crystals with a melting point of 37° C. HPLC content: 96.3%.
by reaction with geranylfarnesyl bromide the 1,4,4a,9a-tetrahydro-9aα-methyl-4aα-[(all-E)-3,7,11,15,19-pentamethyl-2,6,10,14,18-eicosapentaenyl]-1α,4α-methanoanthraquinone as a yellow oil, and therefrom vitamin K 2 (25) as yellow crystals with a melting point of 43.5° C. HPLC content: 99.7%.
EXAMPLE 6
1.3 g (11.6 mmol) of potassium tert.butylate in 10 ml of tert.butanol/toluene (4:1) were placed under argon in a sulphonation flask equipped with a stirrer, a reflux condenser and argon gasification. Thereupon, the mixture was cooled to 0° C. and treated with 1.2 g (4.84 mmol) of 1,4,4a,8aα-tetrahydro-6,7-dimethoxy-4aα-methyl-1α,4.alpha.-methanonaphthalene-5,8-dione in 5 ml of tert.butanol/toluene (4:1). 2.3 g (6.3 mol) of trans-phytyl bromide in 5 ml of tert.butanol/toluene (4:1) were then added dropwise to the red solution obtained at 0° C. within 30 minutes. 10 ml of water were subsequently added to the mixture and the resulting mixture was evaporated on a rotary evaporator. The residue was extracted once with 200 ml of hexane, the extract was washed once with water, then dried over sodium sulphate, filtered and the filtrate was concentrated. There were obtained 2.1 g of a brown oil which was chromatographed on a 70 g SiO 2 column with hexane/ethyl acetate (4:1). There were thus obtained 600 mg of 1,4,4a,8a-Tetrahydro-6,7-dimethoxy-4aα-methyl-8aα-[(E)-3,7,11,15-tetramethyl-2-hexadecenyl]-1α,4α-methanonaphthalene-5,8-dione.
440 mg (0.84 mmol) of the previously obtained oil were dissolved in 3 ml of toluene and heated at reflux under argon for 15 minutes. The mixture was then cooled and concentrated on a rotary evaporator. 390 mg of a red oil were obtained. This oil was chromatographed on a 15 g SiO 2 column with hexane/ethyl acetate (4:1). There were thus obtained 340 mg of phylloubiquinone as a red oil. HPLC content: 89%.
The 1,4,4a,8aα-tetrahydro-6,7-dimethoxy-4aα-methyl-1α,4.alpha.-methanonaphthalene-5,8-dione used as the starting material was prepared as follows:
1.0 g (5.49 mmol) of 2,3-dimethoxy-5-methyl-benzoquinone in 4 ml of acetic acid were placed in a flask. 1.4 ml (16.5 mmol) of 1,3-cyclopentadiene were then added and the mixture was stirred at room temperature. Thereupon, the solution was concentrated at 40° C. on a rotary evaporator, the residue was extracted twice with 200 ml of ether each time, the ether extract was washed three times with water and once with saturated sodium bicarbonate solution, then dried over Na 2 SO 4 , filtered and concentrated. There were obtained 1.5 g of 4aα,5,8,8a-tetrahydro-8aα-methyl-2,3-dimethoxy-5α,8.alpha.-methanonaphthoquinone in the form of an orange coloured oil. This oil was chromatographed on a 45 g SiO 2 column with hexane/ethyl acetate (2:1). This gave 1.23 g of pure 1,4,4a,8aα-tetrahydro-6,7-dimethoxy-4aα-methyl-1α,4.alpha.-methanonaphthalene-5,8-dione.
EXAMPLE 7
The following compounds were manufactured in a manner analogous to Example 6 starting from 1,4,4a,8aα-tetrahydro-6,7-dimethoxy-4aα-methyl-1α,4.alpha.-methanonaphthalene-5,8-dione:
by reaction with geranyl bromide the 4aα-[(E)-3,7-dimethyl-2,6-octadienyl]-1,4,4a,8a-tetrahydro-6,7-dimethoxy-8aα-methyl-1α,4α-methanonaphthalene-dione and therefrom 2,3-dimethoxy-5-methyl-6-[3,7-dimethyloctadien(2,6)-yl]benzoquinone-(1,4). HPLC purity: 100% trans,
by reaction with geranylgeranyl bromide the 1,4,4a,8a-tetrahydro-6,7-dimethoxy-4aα-methyl-8aα-[(all-E)-3,7,11,15-tetramethyl-2,6,10,14-hexadecatetraenyl]-1α,4α-methanonaphthalene-5,8-dione and therefrom 2,3-dimethoxy-5-methyl-6-[3,7,11,15-tetramethyl-hexadecatetraen(2,6,10,14)-yl-(1)]-benzoquinone-(1,4). HPLC purity: 100% all-trans.
by reaction with geranylfarnesyl bromide the 1,4,4a,8a-tetrahydro-6,7-dimethoxy-4aα-methyl-8aα-[(all-E)-3,7,11,15,19-pentamethyl-2,6,10,14,18-eicosapentaenyl]-1α,4α-methanonaphthalene-5,8-dione and therefrom 2,3-dimethoxy-5-methyl-6-[3,7,11,15,19-pentamethyl-eicosapentaen-(2,6,10,14,18)-yl-(1)]-benzoquinone-(1,4). HPLC purity: 95.6% all-trans.
by reaction with solanesyl bromide the 1,4,4a,8a-tetrahydro-6,7-dimethoxy-8aα-methyl-4-aα-[(all-E)-3,7,11,15,19,23,27,31,35-nonamethyl-2,6,10,14,18,22,26,30,34-hexatriacontanonaenyl]-1α,4α-methanonaphthalene-5,8-dione and therefrom 2,3-dimethoxy-5-methyl-6-[3,7,11,15,19,23,27,31,35-nonamethyl-hexatrikontanonaen-(2,6,10,14,18,22,26,30,34)-yl-(1)]-benzoquinone-(1,4). HPLC purity: 98.7% all-trans. | A novel process for the manufacture of quinone derivatives is described.
In this process a compound of the formula ##STR1## is reacted with a compound of the formula ##STR2## and the resulting compound of the formula ##STR3## is subjected to a retro-Diels-Alder reaction. The substituents R 1 , R 2 , R 3 and R 4 have the significance given in the description. | 2 |
BACKGROUND OF THE INVENTION
This invention relates to semiconductor devices and in particular, to bipolar semiconductor devices and means of stabilizing same.
High frequency bipolar transistors, such as those typically used with Emitter Coupled Logic (ECL) circuits, have a tendency of being conditionally stable. Measurements have shown that this conditional stability appears as a negative real part of the input impedance which can cause undesirable oscillations. One solution to this problem is the addition of a resistor in series with the base to cancel the negative resistance and thereby increase stability. This solution can significantly increase the response time of the transistor. Other solutions are to increase the collector resistance, which adversely affects response time, or to significantly increase the collector-base capacitance, which also adversely affects response time. Another solution is to add the series combination of a resistor and transistor between the base and collector of the transistor whose operation is to be stabilized. This solution is very expensive in terms of the added silicon area needed for the implementation thereof.
It would be desirable to be able to compensate for transistor instability without significantly affecting transistor response time, fanout capability, or the physical size of the transistor structure.
SUMMARY OF THE INVENTION
A solution of the above-described problem is attained in an illustrative embodiment of the invention comprising a bipolar transistor having a collector comprising at least first and second regions that are of one conductivity type but are of different impurity concentrations, and a base region of the opposite conductivity type having an active portion through which essentially all collector-emitter conduction occurs and a nonactive portion which is in contact with the first region of the collector region. The first region of the collector has a greater conductivity than the second region of the collector. An emitter region having the same conductivity type as the collector region is located within a portion of the base region. Electrical contacts are made to the base, emitter and collector.
The geometry and resistivity of the nonactive portion of the base determine the value of the effective resistance which is added between the base and the collector. The impurity concentration of the nonactive base and the first region of the collector, as well as the contact area between the nonactive base and the first region, determine the effective capacitance which is in series with the effective resistance between the base and collector. The proper selection of the values of the added series resistance and capacitance negates the negative resistance effect and thus helps insure stable operation.
These and other features of the invention will be better understood from a consideration of the following detailed description taken in conjunction with the following drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates a transistor structure in accordance with one embodiment of the invention; and
FIG. 2 illustrates another transistor structure in accordance with another embodiment of the invention.
DETAILED DESCRIPTION
Referring now to FIG. 1, there is illustrated a cross-sectional view of a semiconductor structure comprising a bipolar transistor 10. Transistor 10, while illustrated as an n-p-n transistor, could also be a p-n-p transistor.
Transistor 10 is illustrated with a p-type substrate 12 and an n+ type buried collector layer 14 with an n+ type deep collector region 18 being in contact therewith. N-type active collector region 20 of transistor 10 is typically a portion of an epitaxial layer. Base region 22 is p-type having an active portion 22A, and a nonactive portion 22B. Regions 24 and 26 are p+ type regions in base regions 22 which allow low resistance ohmic contact thereto. An n++ type collector contact region 32 within region 18 allows low resistance ohmic contact thereto. An n++ type emitter region 28 is illustrated located between regions 24 and 26. Another n++ type region 30 is illustrated within the base region 22 and to the right of region 26. This serves as a passive collector region which forms a p-n junction with the nonactive portion of the base. Region 34 is a p+ type isolation region which extends all around transistor 10. Metal contacts 36, 38 and 40 are illustrated contacting regions 24, 28, and 26, respectively. Metal contact 42 makes low resistance ohmic contact to regions 30 and 32 and serves as the collector contact of transistor 10. Metal contact 42 does not make any contact to the relatively low impurity p-type base 22 or to the relatively low impurity n-type collector 22. An oxide layer (not illustrated) may be used between metal contact 42 and the portions of base 22 and collector 20 that 42 crosses. This provides improved electrical isolation. Alternatively regions 24 and 26 may be parts of an annular region surrounding region 28. Metal contacts 36 and 40 are electrically connected together and serve as the base contact of transistor 10. Metal contact 38 serves as the emitter contact of transistor 10.
During conduction through transistor 10 essentially all of the current flow occurs between emitter 28 and collector 20. Portion 22A of base region 22 (that region near and around emitter 28) is the region through which essentially all transistor emitter-collector conduction occurs and is denoted as the "active base." Portion 22B of base region 22 (that region between regions 26 and 30 and near and around region 30) is denoted as the "nonactive base." There is essentially no conduction from region 30 through 22B to collector 20.
Dashed-lined resistor R1 represents the resistance between base contacts 36 and 40 and passive collector region 30. Dashed-lined capacitor C1 represents the capacitance associated with the p-n junction between regions 22B and 30. As is illustrated, R1 and C1 are essentially serially connected between base contact 40 and collector contact 41. Thus an AC impedance path comprising the series combination of R1 and C1 exists between base contact 40 and collector contact 42 of transistor 10. This electrical path adds a positive ohmic value of R1 to the equivalent series input resistor (not shown) of transistor 10.
It is known that at high frequencies the input impedance looking into the base of a bipolar transistor operating in a circuit can have a negative real part (i.e., resistive part). This could result in undesirable oscillations. The transistor structure 10 of FIG. 1 adds a positive resistance to the normal transistor input resistance and thus effectively cancels the negative input resistance which occurs at high frequencies. This tends to prevent the possibility of oscillations occuring.
The ohmic value of R1 can be controlled by: (1) varying the distance between regions 26 and 30, (2) varying the resistivity of all of base 22; (3) varying the resistivity of base region 22B independently of region 22A; and (4) varying the geometry of region 22B. The capacitive value of C1 can best be controlled by varying the junction area between regions 30 and 22B and/or impurity concentration of region 30. Values for R1 and C1 are selected to compensate for essentially any negative input resistance of transistor 10 at essentially any frequency. This compensation facilitates the stable operation of transistor 10.
The structure of FIG. 1 has been fabricated on a p-substrate of <100>-type silicon material having a resistivity 15 ohms/cm. The sheet resistivity of the material of regions 14, 18, and 20 is approximately 20, 5 and 700 ohms per square, respectively. The sheet resistivity of the material of regions 24, 26, and 22, and regions 28, 30 and 32 is approximately 100, 100, 520, 10, 10, and 10 ohms per square, respectively. The spacing between region 26 and region 30 is 10 microns. Region 30 is 11 microns wide by 29 microns long and has a diffusion depth of about 0.54 microns. The value of R1 is approximately 600 ohms and the value of C1 is approximately 0.4 pF.
Measurements of the input resistance of the fabricated transistor versus frequency indicated that the input resistance stayed positive. The fabricated transistor when used in an emitter follower configuration and connected to emitter coupled logic circuitry exhibited no oscillations under any input conditions. The fabricated transistor is only twenty percent larger than a transistor fabricated using the same design rules but without the added n++ type region in the base.
In standard bipolar transistors, which use a deep heavily doped buried collector, the lightly doped portion of the collector contracts the base and the capacitance of the collector-base junction is generally insufficient to provide a low AC path between the base contact and the collector contact. In addition, the resistance of the base which is in series with the capacitor of the collector-base junction is of insufficient magnitude to provide for cancellation of the negative input resistance which can result during transistor operation. Thus many standard bipolar transistors tend to be conditionally stable.
Now referring to FIG. 2 there is illustrated a cross-sectional view of another semiconductor structure comprising a bipolar transistor 100. Transistor 100 is similar to transistor 10 of FIG. 1 and corresponding regions have the same numerical designation except that an extra 0 is added to the end of each numerical designation. Transistor 100 differs from transistor 10 in that region 30 has been eliminated and region 180 (corresponding to region 18 of FIG. 1) is shifted to the left to a position that coincides with that of region 30 of FIG. 1. In addition, base region 220B is shortened to end at region 180. Transistor 100 is typically thirty percent smaller than transistor 10 of FIG. 1 and ten percent smaller than a standard transistor fabricated using the same design rules. The series combination of R10 and C10 performs the same function as R1 and C1 of FIG. 1.
It is to be understood that the embodiments described herein are merely illustrative of the general principles of the invention. Various modifications are possible within the scope of the invention. For example, region 22B can be terminated at the left edge of region 30 or continued so as to partially surround region 30. Still further, region 30 can be of a different impurity concentration than regions 28 or 32. Still further, region 30 can partially or wholly merge into regions 18 and/or 32. It should be understood that this transistor can be part of an integrated circuit device. | A bipolar transistor structure consists of a standard structure and in addition consists of a low resistance-high impurity concentration region in the collector which contacts a nonactive portion of the base. The resistance between the base contact and the low resistance-high impurity concentration region of the collector, coupled with the capacitance between the two regions, results in the equivalent of a series R-C network between the base contact and the collector contact. The values of resistance and capacitance of this network are selected to insure "absolute" stability of the transistor when operated in a circuit. | 7 |
This application is a division of application Ser. No. 07/467,485, filed Jan. 19, 1990.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to molten metal pumps and, more particularly, to a molten metal pump having an attached filter.
2. Description of the Prior Art
In the course of processing molten metal, it often is necessary to transfer the molten metal from one vessel to another or to circulate the molten metal within a given vessel. Molten metal pumps commonly are used for these purposes. The pumps also can be used for other purposes, such as to inject purifying gases into the molten metal being pumped. A variety of pumps as described are available from Metaullics Systems, 31935 Aurora Road, Solon, Ohio 44139, under the Model designation M12 et al.
In the particular case where molten metal is melted in a reverberatory furnace, the furnace is provided with an external well in which a pump is disposed. The pump draws molten metal from the furnace and either circulates the molten metal through the external well (from which it is re-introduced into the furnace), or it transfers the molten metal out of the well to another vessel. Typically, a thermocouple will be placed in the well in order to feed back the temperature of the molten metal to the furnace for appropriate control of the furnace.
A problem with the foregoing arrangement is that foreign material such as dross, solids, or semi-solids (hereinafter referred to as "particles") contained in the well can be drawn into the molten metal pump. If large particles are drawn into the pump, the pump can be jammed, causing catastrophic failure of the pump. Even if catastrophic failure does not occur, the particles can degrade the performance of the pump or negatively affect the quality of a casting made from the molten metal.
In addition to the problems posed by drawing large particles into the pump, a problem also exists with respect to drawing small particles, on the order of 100 microns or less, into the pump. Although small particles cannot cause catastrophic failure of the pump, they still can negatively affect the quality of a casting made from the molten metal. There is a need to positively filter the molten metal prior to using the molten metal in a casting process. While so-called "downstream" filters have been used to filter the molten metal prior to its introduction into a mold, the filtration burden imposed on downstream filters will be lessened if the molten metal has been fine-filtered at some upstream location. In view of the drawbacks associated with unfiltered molten metal pumps, it has become desirable to attempt to remove particles from the molten metal prior to passage of the molten metal through the pump.
One approach that has been attempted is a so-called gate filter. A gate filter is a porous barrier that is interposed between the furnace and the external well immediately upstream of the pump. In theory, a gate filter will remove particles being circulated out of the furnace, thereby avoiding ingestion of those particles into the pump. In practice, several difficulties have arisen. First, it has been found difficult to install the filter, in part because a frame must be provided for the filter at the junction between the furnace and the well. Second, the filter tends to be lifted by the molten metal, thereby permitting particles to flow into the well underneath the raised filter. Third, a thermal gradient can exist in the metal across the filter from the "hot" side to the "cold" side. The temperature of the molten metal in the well can be lower than the temperature in the furnace on the order of 50°-752° F. Because the temperature sensor for the furnace often is located in the well, the lowering of the temperature of the molten metal in the well causes the control system for the furnace to unnecessarily activate the combustion system for the furnace. In turn, excessive heat generated by the furnace causes even more particles to be formed. An additional problem is that oxides and dross formed in the pump well can be drawn into the pump.
Another approach that has been attempted is to suspend the pump within a liquid-permeable filter basket. In effect, the basket acts as a filter for the pump. A drawback of the basket approach is that it is difficult to properly position the pump relative to the basket. The basket must be rested on, or adjacent to, the floor of the well, and the pump must be properly suspended within the basket. Additionally, the basket must be relatively large in order to extend completely above the upper surface of the molten metal. Because the basket extends out of the molten metal, it must be insulated in some manner in order to minimize heat losses through the upper surface. Also, because the basket is so large, its cost is greater than desired.
One approach that has been effective is disclosed in U.S. Pat. No. 4,940,384, issued Jul. 10, 1990 to L. H. Amra, et al., entitled "Molten Metal Pump with Filter," (hereinafter referred to as the "Pump Filter Patent"), the disclosure of which is incorporated herein by reference. In the Pump Filter Patent, a filter is attached to a base of a pump so as to surround the inlet of the pump. Preferably, the filter is made of a porous, bonded (fired or sintered), refractory substance such as silicon carbide and/or alumina. The surface area of the pump is quite large relative to the inlet area of the pump. Due to the configuration of the filter, a large cavity is created that is defined by the interior of the filter and the bottom surface of the pump.
Due to the configuration of the filter and its relationship to the pump, the filter can have a very low porosity, for example, approximately 35-38 percent. The filter not only filters coarse particles that can ruin the pump, but it also filters fine particles that can negatively affect a casting. The filter can be cleaned easily and, when cleaning no longer is feasible, it can be removed and replaced without difficulty. The compactness of the filter minimizes installation difficulties and it also minimizes the expense of the filter.
Despite the advantages of the filter arrangement disclosed in the Pump Filter Patent, certain problems have not been addressed. One of those problems relates to the strength of the filter and the integrity of the filter-pump attachment. Desirably, the filter would be as strong as possible, and it would be attached to the pump in a manner that not only would enhance the strength of the filter, but it also would provide additional support for the base of the pump. Another problem not addressed by the Pump Filter Patent is the possible removal of an impeller and supporting shaft for purposes of repair or replacement without disturbing the attachment between the filter and the pump. Desirably, the filter would be constructed such that the filter could remain attached to the pump while permitting the impeller and shaft to be removed for purposes of repair or replacement.
In view of the approaches that have been described, there remains a need for an effective technique for filtering molten metal being passed through a molten metal pump. It is hoped that any such technique would be inexpensive, easy to work with, and would avoid the drawbacks and address the noted problems of the approaches described above.
SUMMARY OF THE INVENTION
The present invention provides a new and improved technique for filtering molten metal being pumped by a molten metal pump. In one embodiment, the invention includes a filter that is attached to the base of the pump so as to surround the inlet of the pump. As in the Pump Filter Patent, the filter is made of a porous, bonded (fired or sintered), refractory substance such as silicon carbide and/or alumina. The surface area of the filter is quite large relative to the inlet area of the pump. Due to the configuration of the filter, a large cavity is created, which cavity is defined by the interior of the filter and the bottom surface of the pump.
The filter according to the invention is an improvement over the filter disclosed in the Pump Filter Patent. The filter according to the invention includes, in cross-section, an end wall having a plurality of corrugations. A plurality of tabs project from the corrugated sections disclosed closest to the pump. The tabs are in contact with the base member, and are secured there by means of a cemented connection. The corrugations not only increase the surface area of the filter for more effective filtering action, but the cemented connection between the tabs and the base member enhances the strength of the filter and the filter-base member connection.
As in the Pump Filter Patent, the filter can have a very low porosity, for example, approximately 35-38 percent. The filter not only filters coarse particles that can ruin the pump, but it also filters fine particles that can negatively affect a casting. The filter according to the invention can be cleaned easily and, when cleaning no longer is feasible, it can be removed and replaced without difficulty. The compactness of the filter minimizes installation difficulties, and it also minimizes the expense of the filter.
In an alternative embodiment of the invention, the base member includes an inlet along one side and an opening along a bottom surface through which access to the impeller may be had. In this alternative embodiment, the filter is a semi-toroidal structure defined by an outer wall, an inner wall, and an end wall connecting the outer and inner walls. The filter is connected to the base member by cemented connections made at the ends of outer and inner walls. The diameter of the inner walls is such that a portion of the bottom surface of the base member is exposed, which exposed portion includes the opening through which access may be had to the impeller. The filter not only surrounds the pump's inlet as in the first-described embodiment, but it also enables the impeller and its associated shaft to be removed from the bottom of the base member without disturbing the filter-base member connection. Accordingly, the filter provides effective filtering action as in the first-described embodiment, and it also permits the impeller and its associated shaft to be removed conveniently from the pump for purposes of repair or replacement.
The foregoing and other features and advantages of the invention are illustrated in the accompanying drawings and are described in more detail in the specification and claims that follow.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic, perspective view of the external well of a reverberatory furnace into which a molten metal pump has been immersed;
FIG. 2 is a cross-sectional view of the pump of FIG. 1;
FIG. 3 is a cross-sectional view of an alternative embodiment of the pump of FIG. 1;
FIG. 4 is an enlarged cross-sectional view of the lower portion of the pump of FIG. 3; and
FIG. 5 is an enlarged cross-sectional view of the pump of FIG. 3 taken along a plane indicated by line 5--5 in FIG. 4.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIGS. 1 and 2, a molten metal pump according to the invention is indicated generally by the reference numeral 10. The pump 10 is adapted to be immersed in molten metal contained within a vessel 12. The vessel 12 can be any container containing molten metal, although the vessel 12 as illustrated is the external well of a reverberatory furnace.
It is to be understood that the pump 10 can be any type of pump suitable for pumping molten metal. Generally, however, the pump 10 will have a base member 14 within which an impeller 16 is disposed. The impeller 16 includes an opening 17 along its bottom surface that defines a fluid inlet for the pump 10. The impeller 16 is supported for rotation within the base member 14 by means of an elongate, rotatable shaft 18. The upper end of the shaft 18 is connected to a motor 20. The motor 20 can be of any desired type, although an air motor is illustrated.
The base member 14 includes an outlet passageway 22. A riser 24 is connected to the base member 14 in fluid communication with the passageway 22. A flanged pipe 26 is connected to the upper end of the riser 24 for discharging molten metal into a spout or other conduit (not shown). The pump 10 thus described is a so-called transfer pump, that is, it transfers molten metal from the vessel 12 to a location outside of the vessel 12. As indicated earlier, however, the pump 10 is described for illustrative purposes and it is to be understood that the pump 10 can be of any type suitable for the pumping of molten metal.
The base member 14 includes a shoulder portion 28 about its lower periphery. The shoulder portion 28 circumscribes the fluid inlet 17 defined by the impeller 16. The base member 14 is circular in plan view and, thus, the shoulder portion 28 is circular. If the base member 14 were to be of a non-circular cross-section, then the shoulder portion 28 should conform to the shape of the base member 14.
A generally cylindrical, cup-like filter 30 is connected to the base member 14 so as to completely surround the fluid inlet 17. The filter 30 includes a cylindrical side wall 32 and a corrugated end wall 34. In cross-section, the end wall 34 is defined by alternating straight portions 36 having rounded ridges 38 and rounded troughs 40. Tabs 42 project from the ridges 38 and contact the bottom surface of the base member 14. The tabs 42 are spaced so as to define openings 44 therebetween. The openings 44 permit filtered molten metal to be drawn into the fluid inlet 17. The side wall 32 is adapted to mate tightly with the shoulder portion 28, and to be secured there by means of refractory cement such as that sold under the trademark FRAXSET by Metaullics Systems of Solon, Ohio. FRAXSET refractory cement has exceptional strength and resistance to corrosion in molten aluminum and zinc applications. Similarly, the tabs 42 are attached to the base member 14 by means of FRAXSET refractory cement.
It is expected that the filter 30 will be a porous structure formed of bonded or sintered particles such as 6-grit silicon carbide or alumina. A suitable filter made of 6-grit silicon carbide or alumina is commercially available from Metaullics Systems of Solon, Ohio. The filter 30, when manufactured of 6-grit silicon carbide or alumina, has a porosity of approximately 35-38 percent. Other grit sizes may be employed for finer or coarser filtration as may be desired, it being recognized that changing the grit size will affect the flow rate of the filter 30. The filter 30 is refractory due to the material from which it is made, and thus it will withstand the temperatures encountered in the processing of molten, non-ferrous metals.
The size of the filter 30 will depend upon the pumping capabilities of the pump 10. As illustrated, the side wall 32 is approximately 7.0 inches high and has an outer diameter of approximately 14.125 inches. The side wall 32 projects approximately 6.0 inches beyond the lowermost portion of the base member 14 (the distance from the bottom of the base member 14 to the bottom of the troughs 40). The filter 30 has a uniform wall thickness of approximately 1.0 inch. For the dimensions given, the filter 30 has an external surface area of about 525.5 square inches.
The filter 30 defines a portion of a cavity 46, which cavity 46 is bounded by the interior surface of the side wall 32, the interior surface of the end wall 34, and the bottom surface of the base member 14. The inlet area of the pump is approximately 4.75 square inches (as measured by the internal diameter of the impeller 16). Accordingly, the ratio of the exterior surface area of the filter 30 to the area of the pump inlet is approximately 110.63.
Using the exterior surface area of the filter 30 as a reference, and assuming that the molten metal being pumped has a 12-inch head, and further assuming a flow capacity of 240 pounds per minute per square foot per inch-head, the theoretical flow rate of the filter 30 is approximately 10,510 pounds per minute. In practice, the pump 10 has a flow rate with a 12-inch head of approximately 750 pounds per minute. Accordingly, the filter 30 provides a safety factor of approximately 14 to 1 in operating flow rate capability.
An Alternative Embodiment
Referring to FIGS. 3-5, another molten metal pump according to the invention is indicated generally by the reference numeral 50. The pump 50 is quite similar to the pump 10, and is intended to be used for the same purposes and under the same conditions. Where appropriate, the same reference numerals will be carried over from FIGS. 1 and 2 to FIGS. 3-5 in order to indicate components that are identical, or substantially identical.
The pump 50 includes a base member 52 that is configured differently than the base member 14. In particular, the base member 52 includes three laterally extending openings 54 that define fluid inlets for the pump 50. The openings 54 are located near the upper portion of the base member 52. An impeller 56 is disposed within the base member 52 and is supported for rotation therein by an impeller shaft 57. The base member 52 includes an opening 58 in its lower surface that closely matches the outer diameter of the impeller 56. A pair of optional refractory posts 59 (FIG. 5) provide support for the base member 52. The posts 59 are used with certain molten metal pumps but not with others, depending upon the design of the pump, as is known to those skilled in the art.
A pumping chamber 60 is included as part of the base member 52. The impeller 56 is disposed within the pumping chamber 60. An outlet passageway 62 is in fluid communication with the pumping chamber 60 and discharges pumped molten metal to the riser 24 and the flanged pipe 26. The impeller 56 includes a plurality of openings 64 that provide fluid communication between the openings 54 and the pumping chamber 60. Upon rotation of the impeller 56, fluid will be drawn through the openings 54, into the impeller 56, and thereafter will be pumped out of the pumping chamber 60 through the outlet passageway 62.
A semi-toroidal filter 70 is connected to the base member 52 so as to completely surround the fluid inlet 54. The filter 70 includes a cylindrical outer side wall 72, a cylindrical inner side wall 74, and an annular end wall 76 that closes the side walls 72, 74. The filter 70 defines a portion of a cavity 78, which cavity 78 is bounded by the interior surfaces of the side walls 72, 74, the end wall 76, and the bottom and side surfaces of the base member 52.
As with the filter 30, the size of the filter 70 will depend upon the pumping capabilities of the pump 50. As illustrated, the side wall 72 is approximately 9.0 inches high and has an outer diameter of approximately 19.0 inches. The inner side wall 74 is approximately 4.0 inches high and has an inner diameter of approximately 9.0 inches. Accordingly, the outer surface of the side wall 72 has a radius approximately 5.0 inches greater than the radius of the outer surface of the side wall 74. As with the filter 30, the filter 70 has a uniform wall thickness of approximately 1.0 inch.
For the dimensions given, the filter 70 has an external surface area of about 840 square inches. The inlet area of the pump is approximately 6.95 square inches (as measured by the smallest area of the inlet openings 54). Accordingly, the ratio of the exterior surface area of the filter 70 to the area of the inlet openings 54 is approximately 120.9
Using the external surface area of the filter 70 as a reference, and assuming that the molten metal being pumped has a 12-inch head, and further assuming a flow capacity of 240 pounds per minute per square foot per inch head, the theoretical flow rate of the filter 70 is approximately 1,680 pounds per minute. In practice, the pump 50 with a 12-inch head has a flow rate of approximately 3,000 pounds per minute. Accordingly, the filter 70 provides a safety factor of approximately 5.6 to 1 in operating flow rate capability.
As with the filter 30, the filter 70 is tightly fitted to the side of the base member 52 and is secured there by means of FRAXSET refractory cement. It is expected that the filter 70 will be constructed of the same material of the filter 30 and, therefore, the specifications provided earlier for the filter 30 apply equally to the filter 70.
The present invention provides significant advantages compared with gate filters or basket filters. Because the filter 30 is integral with the base member 14, the pump 10 can be positioned as desired without concern for maintaining a proper relationship between the base member 14 and the filter 30. The position of the filter 30 relative to the vessel 12 can be adjusted simply by raising or lowering the pump 10. It is expected that the end wall 34 will be positioned approximately two or three inches from the bottom of the vessel 12, although any desired spacing can be chosen. The corrugated end wall 34 not only provides more surface area than the filter disclosed in the Pump Filter Patent, but it also is stronger due to (a) the inherent strength arising from a corrugated end wall configuration, and (b) the support provided by the tab-base member connection.
Because the filter 30 is completely immersed within the molten metal, it does not conduct heat out of the bath as is the case with a gate filter or a basket filter. Thermal gradients often associated with gate filters are eliminated because the filter is integral with the pump and a fully open passageway is maintained between the furnace and the external well. Further, the characteristics of the filter 30 not only enable exceedingly fine as well as coarse particles to be filtered, but the permeability of the filter is such that the pump's flow capability can be maintained. Due to the particular configuration of the filter 30 and due to the material from which it is made, the filter 30 can be cleaned easily and, when replacement is necessary, the cost to the user will be less than with a gate filter or a basket filter.
In the particular case of the filter 70, the central opening defined by the inner side wall 74 enables the impeller 56 and the shaft 57 to be removed as a unit upon disconnecting the upper end of the shaft 57 from the drive motor 20. The shaft 57 and the impeller 56 can be removed from the bottom of the base member 52 through the opening 58 without disturbing the attachment between the base member 52 and the filter 70. This feature represents an advantage compared with the filter 30, because it is necessary to remove the filter 30 in order to provide access to the impeller 16 for purposes of inspection or replacement. While the filter 30 is relatively inexpensive and easy to remove and replace, nevertheless it can be an advantage under certain circumstances to be able to remove the impeller 56 and the shaft 57 without disturbing the connection between the base member 52 and the filter 70.
Although the invention has been described in its preferred form with a certain degree of particularity, it will be understood that the present disclosure of the preferred embodiment has been made only by way of example and that various changes may be resorted to without departing from the true spirit and scope of the invention as hereinafter claimed. It is intended that the patent shall cover, by suitable expression in the appended claims, whatever features of patentable novelty exist in the invention disclosed. | A molten metal pump includes a filter that prevents ingestion of foreign material such as dross from molten metal within which the pump is immersed. The filter is a large structure that is secured to the base of the pump surrounding the pump's inlet. The filter forms a cavity adjacent the pump's inlet. The ratio of the surface area of the filter to the inlet area of the pump is very large due in part to a corrugated end wall included as part of the filter. The filter has a low porosity while maintaining a high flow rate for the pump. | 5 |
CROSS REFERENCE
This application is a continuation-in-part of the United States patent application entitled “Receiver Based Method for DeSpreading of Spread Spectrum Signal,” filed on Nov. 13, 2003, having a U.S. application Ser. No. 10/712,643.
FIELD OF INVENTION
The present invention relates to spread spectrum communications, and in particular, to methods and receiver despreader architectures for despreading spread spectrum signals.
BACKGROUND
Spread spectrum communications system spread information over bandwidths much larger than those actually required to transmit the information. The spread spectrum technologies have been widely used both in military and commercial wireless communication systems such as the Global Positioning System (GPS), IS2000 mobile communications systems, and applications based on the emerging IEEE 802.15.4 standard. The advantages of using the spread spectrum approach are many. Spread spectrum systems are very robust with respect to noise and interferences due to the spreading gain. These systems are also inherently secure where multi-path fading has a lesser impact.
In the IEEE 802.15.4 standard, the transmitted data stream are grouped into 4 bits as a symbol and mapped and spreaded, i.e., encoded into 16 ary Psuedo Noise (PN) spreading codes where each of the 16 possible symbols is represented by a 32 bit PN code. Table 1 shows the 16 spreading PN codes defined by the IEEE 802.15.4 standard (“original PN codes”) where Symbol 0 through Symbol 15 is mapped into Codes 1 through 16. Each code is 32-bit long and represents 4 binary digits. The codes are designed to have the following properties: (1) Codes 2 to 8 are obtained by cyclicly shifting right 4, 8, 12, 16, 20, 24, 28 bits of the first code (symbol 0); and (2) Codes 9 to 16 are the inversion of odd-indexed chip value of codes 1 to 8.
TABLE 1
Original PN Code
SYM
ORIGINAL PN CODES
0
11011001110000110101001000101110
1
11101101100111000011010100100010
2
00101110110110011100001101010010
3
00100010111011011001110000110101
4
01010010001011101101100111000011
5
00110101001000101110110110011100
6
11000011010100100010111011011001
7
10011100001101010010001011101101
8
10001100100101100000011101111011
9
10111000110010010110000001110111
10
01111011100011001001011000000111
11
01110111101110001100100101100000
12
00000111011110111000110010010110
13
01100000011101111011100011001001
14
10010110000001110111101110001100
15
11001001011000000111011110111000
In order to utilize the full potential of spread spectrum systems, spreading codes such as the original PN codes are constructed to have good auto- and cross-correlation properties. That is, with correlation during despreading, one code can effectively differentiate itself from the other codes under noisy conditions. FIG. 1 shows the cross-correlation properties of the original PN codes for the 2.4 GHz band between Code 1 and Codes 0-15. The first point represents the code correlating to Code 1 and its auto-correlation output. The correlation peak ( FIG. 1 , Code Index 1, value 32) appears when Code 1 correlates to itself. The second point represents the code correlating to Code 2 and its cross-correlation output and so on.
The spreaded PN codes are modulated using minimum shift keying (MSK) modulation schemes before transmission. MSK modulations schemes have many robust features and have been adopted in standards such as GSM, Bluetooth, and DECT.
A spreaded spectrum receiver has to demodulate and then despread the received signal with spreading codes. A typical implementation of these processes is shown in FIG. 2 . Here, the received signal is first demodulated ( 22 ). Then, the demodulated signal is processed ( 24 ) using the spreading codes to generate the despread output by multiplying the demodulated received code with the spreading codes ( 26 ) and accumulating the products of the multiplication ( 28 ). The despread output is then used for bit or symbol decision-making or as input for error correction processing.
The receiver demodulation of MSK modulated signals can be either coherent or non-coherent demodulation. However, the receiver architecture of coherent demodulation is more complex and is more expensive to implement. In addition to data path match filtering, despreading and demapping, the coherent receiver requires carrier recovery and timing recovery circuits to determine the phase and frequency of carrier and timing clock in order to successfully recover the data stream. Therefore, coherent demodulation scheme of MSK signals are seldom adopted in industry due to the high cost in implementation.
The use of differential demodulation, a non-coherent demodulation, as the MSK demodulation scheme eliminates the necessity of carrier recovery circuits. Differential demodulation converts carrier frequency offset into DC offset thus requiring only DC removal circuits that are much simpler than carrier recovery circuits.
However, the unique properties of original PN codes are lost and changed after differential demodulation. The differential demodulated signals will require a new set of differential encoded PN codes for despreading with the use multiple correlators.
U.S. patent application Ser. No. 10/712,643 provides a novel receiver transformer that transforms the received demodulated signal. It also transforms the original PN sequence into a transformed differential encoded PN codes (“Differential Encoded PN Codes”) as shown in Table 2 for subsequent processing of the transformed received signal. With special setting on the initial condition of the differential encoded PN sequence, this Differential Encoded PN Codes have better properties than the original PN codes. The new codes have the following superior properties: (1) Code 2 (symbol 1) to Code 8 (symbol 7) are obtained by cyclicly shifting right 4, 8, 12, 16, 20, 24, 28 bits of the first code (symbol 0); and (2) Codes 9 (Symbol 8) to Codes 16 (Symbol 15) are the inversion of Codes 1 to 8. These new, superior properties allow a simple despeader/demapper implementation.
TABLE 2
Differential Encoded PN Codes
SYM
DIFFERENTIAL PN CODES
0
11100000011101111010111001101100
1
11001110000001110111101011100110
2
01101100111000000111011110101110
3
11100110110011100000011101111010
4
10101110011011001110000001110111
5
01111010111001101100111000000111
6
01110111101011100110110011100000
7
00000111011110101110011011001110
8
00011111100010000101000110010011
9
00110001111110001000010100011001
10
10010011000111111000100001010001
11
00011001001100011111100010000101
12
01010001100100110001111110001000
13
10000101000110010011000111111000
14
10001000010100011001001100011111
15
11111000100001010001100100110001
However, the despreading of Table 2 differential encoded PN codes is customarily accomplished using 16 correlators, one for each code of the differential encoded PN codes. Each received code of a demodulated transformed received signal has to be correlated with the 16 correlators to determine the maximum value of the correlation in order to determine the corresponding symbol for that received code. The hardware implementation of this method of despreading is very expensive and has to occupy a lot of ASIC area. In addition, this method of despreading requires the use of timing recovery circuits to address the timing shift caused by the sampling clock mismatch between the transmitter and the receiver.
Therefore, it is desirable to have innovative methods for despreading spread spectrum signals to overcome the shortcoming of prior art technologies.
SUMMARY OF INVENTION
It is therefore an object of the present invention to provide simple methods for despreading of spread spectrum signals.
It is another object of the present invention to provide methods for generating correlation codes such that only one correlator is required for the despreading of spread spectrum signals.
It is another object of the present invention to provide methods for despreading spread spectrum that is robust to timing frequency shifts generated between the transmitter and receiver clocks.
This invention provides novel methods for the despreading and demapping of demodulated signals, transformed and mapped into a set of Differential Encoded PN Codes, into its original symbols by the use of a single correlation code. Novel single correlation codes are generated from one of the symbols that has been mapped into the Differential Encoded PN Codes. Each received code of a received spreaded signal is correlated with said generated single correlation code to obtain despreading output samples of the despreading output. The index for the maximum positive or negative peak of the despreading output samples is identified, and then mapped into a symbol corresponding to the transmitted information.
This invention also provides novel receiver despreader architecture for each code of despreading received spreaded signals comprising of shift registers with taps attached to the inputs of said shift registers. Received samples of each received spreaded code are inputted into the shift registers. An embodiment of the receiver despreader architecture operates to calculate the despreading output samples of the despreading output by accumulating the products of the multiplication of the input to the shift registers with predetermined values associated with the taps. The predetermined value associated with a tap corresponds to the value of the correlation samples of the generated correlated codes. The despreading output index for the maximum of the absolute values of the despreading output samples is identified and then mapped into a symbol corresponding to the transmitted signal.
An advantage of the present invention is that it provides simple methods for despreading of spread spectrum signals.
Another advantage of the present invention is that it provides methods for generating correlation codes such that only one correlator is required for the despreading of spread spectrum signals.
Another advantage of the present invention is that it eliminates the need for timing recovery circuits to track sampling clock frequency mismatches between the transmitter and receiver.
DESCRIPTION OF DRAWINGS
The foregoing and other objects, aspects and advantages of the invention will be better understood from the following detailed description of preferred embodiments of this invention when taken in conjunction with the accompanying drawings in which:
FIG. 1 illustrates the cross-correlation properties of the original PN codes for the 2.4GHz band between Symbol 0 and Symbols 0-15.
FIG. 2 illustrates a typical implementation of the despreading process.
FIG. 3 illustrates a presently preferred despreading architecture of the present invention.
FIG. 4 is an illustration of a despreading output of an embodiment.
FIG. 5 shows the despreading output indexes.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
This invention provides innovative methods and receiver architectures for the despreading and demapping the codes of demodulated signals into its original symbols by the use of a single correlation code. These demodulated signals have been transformed and mapped into a set of a set of differential encoded PN codes before the despreading process. Methods for generating these single correlation codes are developed by exploiting the unique functional inter-relationships between the different codes in the set of differential encoded PN codes. These methods of despreading also eliminate the necessity of timing recovery circuits and the use of multipliers at the same time.
After demodulation, a received signal contains codes to be despreaded for symbol decision-making. Each received spreaded code r x is series of received samples r x (k) where r x (k) denotes the kth received sample of the received code that is being despreaded and k is the received index of said received sample.
The initial clock timing and PN code phase are acquired during signal detection of preambles such that the despreader know where to start despreading the incoming received signals. The method for despreading a received code involves the use of a single correlation code and comprises of the following steps:
generating a despreading output as a function of said received spreaded code and said single correlation code;
identifying the despreading output index of the maximum of the absolute value of said despreading output, k max ; and
mapping k max into a symbol of a set of symbols corresponding to the transmitted signal.
The following embodiment illustrates the method and despreader architecture for the despreading of 64-sample received codes corresponding to a transmitted signal whose symbols have been spreaded and mapped into the Differential Encoded PN Codes of Table 2.
The Generation of A Correlation Code
The first step in this despreading is to generate a correlation code by utilizing the functional relationships between the codes in the set of differential encoded PN codes Once this single correlation code is generated, it is used for the despreading of all received spreaded codes. The following preferred embodiment generates a correlation code, C 128 , for a received spreaded code having 64 received samples that have been spreaded and mapped into the Differential Encoded PN Codes of Table 2. It can be generated by using Symbol 0 corresponding to Code 1. For received spreaded codes that has been transformed and mapped into the 16 ary Differential PN Codes, correlation codes corresponding to the other 15 codes can be similarly constructed. However, only one correlation code needs to be generated since only one is needed for the despreading.
Here, C 128 has 128 samples. It is generated by Symbol 0 of Table 2 that has been upsampled twice, repeated, and shifted by 4 samples and mapped. If the 32 bits of Symbol 0 is denoted by [d 0 . d 1 , d 2 , d 3 , . . . d 29 , d 30 , d 31 ], the correlation code with 128 samples is generated as follows:
(1) Symbol 0 is mapped into a 32 sample code denoted by: [c 0 , c 1 , c 2 , . . . c 29 , c 30 , c 31 ] where c i =d i =1 when d i =1, and c i =−1, when d i =0 where c i is the ith sample of the mapped function and d i denotes the ith bit in Symbol 0;
(2) This mapped function is upsampled by inserting zeroes after each c i to form a 64 sample code denoted by [c 0 , 0, c 1 , 0, c 2 , 0, . . . c 29 , 0, c 30 , 0, c 31 , 0];
(3) The above code is repeated to form a 128 sample code denoted by: [c 0 , 0, c 1 , 0, c 2 , 0, . . . c 29 , 0, c 30 , 0, c 31 , 0, c 0 , 0, c 1 , 0, c 2 , 0. . . c 29 , 0, c 30 , 0, c 31 0];
(4) The last 4 samples of this 128 sample code is then cyclicly shifted right to become the first 4 correlation code samples of the correlation code C 128 having 128 correlation code samples represented by:
C 128 =[c 30 , 0, c 31 , 0, c 0 , 0, c 1 , 0, c 2 , 0, . . . c 29 , 0, c 30 0, c 31 , 0, c 0 , 0, c 1 , 0, c 2 , 0, . . . c 29 , 0]
For the correlation code generated with Symbol 0,
C 128 = [ - 1 0 - 1 0 1 0 1 0 1 0 - 1 0 - 1 0 - 1 0 - 1 0 - 1 0 - 1 0 1 0 1 0 1 0 - 1 0 1 0 1 0 1 0 1 0 - 1 0 1 0 - 1 0 1 0 1 0 1 0 - 1 0 - 1 0 1 0 1 0 - 1 0 1 0 1 0 - 1 0 - 1 0 1 0 1 0 1 0 - 1 0 - 1 0 - 1 0 - 1 0 - 1 0 - 1 0 1 0 1 0 1 0 - 1 0 1 0 1 0 1 0 1 0 - 1 0 1 0 - 1 0 1 0 1 0 1 0 - 1 0 - 1 0 1 0 1 0 - 1 0 1 0 1 0 ] .
Generation of Despreading Output by Multiplying and Accumulating the Received Spreaded Code with the Correlation Code
One method to calculate the despreading outputs of a received code is by accumulating the multiplication of the correlation codes samples of the correlation code with the received samples of the received code. In the embodiment where the received code has 64 received samples and r x (n) is the nth sample of the received signal where 1≦n≦64, one method to calculate r c (k), the kth sample of the 64 sample despreading output, also called the correlation output, is to accumulate the multiplied products of the received code with the correlation code C 128 . That is, the (n+k)th correlation code sample of the correlation code, C 128 (n+k), is multiplied by the nth received sample of the received code, r x (n), for each of the 64 received samples of the received code and the products of the multiplication for all 64 samples are accumulated to become r c (k). This process can be represented mathematically as follows:
r c ( k ) = ∑ n = 1 N r x ( n ) C 128 ( k + n ) ,
1 ≤ k ≤ N where N = 64 Equation ( 1 )
Identifying k max , the Despreading Output Index of the Maximum of the Absolute Value of said Despreading Output
The 64 samples of the despreading output, r c (k), for each k between 1 and 64 can be calculated using Equation (1) for 1≦k≦64. The maximum of the absolute value of the despreading output, i.e., the positive peak or the negative peak of the despreading output can be found. This maximum despreading output identifies the despreading ouput index k max corresponding to the either the positive or negative peak of the despreading output samples, r c (k). Mathematically k max is defined by the following equation.
r c ( k max ) = max 1 ≤ k ≤ N r c ( k ) Equation ( 2 )
Symbol Decision Making by Mapping k max into a Symbol in a Set of Symbols Corresponding to the Transmitted Information
Once k max , is identified, it can be used to map the received code to the original symbols, i.e., the original symbols of the transmitted signal in a set of symbols that have been mapped into said set of Differential Encoded PN codes. The despreading outputs have 64 despreading output samples and each 8 despreading output samples of the despreading output can be mapped to one symbol. Since, the PN codes contain 16 symbols to despread, the unique feature of these differential encoded spreading codes is needed to identify the received output for the symbols 8 through 15. In the differential encoded PN codes, the first 8 codes are exactly the inverse of the last 8 codes. If a code among the last 8 symbols is received, the received output r c (k) will be a negative peak. Therefore, positive peaks in the despreading outputs map to first 8 symbols while the negative peaks map to last 8 symbols. In other words, if r c (k max )>0, when 1≦k max ≦8, the received spreaded code is despreaded and mapped into Symbol 0. When 9≦k max ≦16, the received spreaded code is despreaded and mapped into Symbol 1, and so on. If r c (k max )<0, when 1≦k max ≦8, the received spreaded code is despreaded and mapped into Symbol 8, when 9≦k max ≦16, the received spreaded code is despreaded and mapped into Symbol 9, and so on. Ideally, for perfect received code with no frequency mismatch, k max , the despreading output indexes of the maximum of the absolute value of the despreading output samples are at 5, 13, 21, 29, 37, 45, 53, and 61. They correspond to the symbols 0, 1, 2, 7 if r c (k max )>0 and correspond to symbols 8, 9, . . . 15 when r c (k max )<0 With timing frequency offset, the peaks of the despreading outputs will move from those perfect positions because the sampling phase offset.
Another method to map the symbol corresponding to the received code is to compute an index m with the following equation:
m = ( 9 - ⌈ k max 8 ⌉ ) mod 8 if r c ( k max ) ≥ 0 Equation ( 3 ) m = ( 9 - ⌈ k max 8 ⌉ ) mod 8 + 8 if r c ( k max ) ≤ 0. Equation ( 4 )
Index “m” denotes the corresponding number of the symbol that has been mapped into the PN codes. In other words, for r c (k max )>0, and 1≦k max ≦8, then m=0 and the code received corresponds to Symbol 0. Similarly, m corresponds to the Symbol m for 1+8* m≦k max ≦8*(m+1) for r c (k max )>0.
The above-described methodology can similarly be used to despread multiple codes in the received signal. Thus, if r x (n,l) denotes the nth sample of the lth code of the received codes, and r c (k,l) denotes the kth sample of the despreading output samples for the for the lth code, then the following equations defines k max , l, the despreading output index for the lth code, and m (l), the index for the lth code corresponding to the number of the symbol for the lth code as listed in the Table 2.
r
c
(
k
,
l
)
=
∑
n
=
1
N
r
x
(
n
,
l
)
C
128
(
k
+
n
)
1
≤
k
≤
N
,
where
N
=
64
Equation
(
1
a
)
r
c
(
k
max
,
l
,
l
)
=
max
1
≤
k
≤
N
r
c
(
k
,
l
)
Equation
(
2
a
)
m
(
l
)
=
(
9
-
⌈
k
max
,
l
8
⌉
)
mod
8
if
r
c
(
k
max
,
l
)
≥
0
Equation
(
3
a
)
m
(
l
)
=
(
9
-
⌈
k
max
,
l
8
⌉
)
mod
8
+
8
if
r
c
(
k
max
,
l
)
≤
0
Equation
(
4
a
)
Examples of despreading outputs obtained by the method in this embodiment is illustrated in FIG. 4 where the y axis denotes the despreading output samples r c (k,l) for different despreading output indexes for each code “l” on the x axis. The thin lines are the noise floors, i.e., r c (k,l) for each k and l where the despreading output is not at its maximum while the thick line is the maximum values for the despreading outputs, i.e.,
r c ( k max , l , l ) = max 1 ≤ k ≤ N r c ( k , l ) .
The noise floor for this example is high as the signal to noise ratio, SNR, is 8 dB. However, even with this high SNR, and the maximum values of the despreading output, r c (k max , l) is not far from other spreading output r c (k, l) where k≠k max , the symbol decision making can be accomplished correctly after despreading, as long is the maximum still occurs with the 8 sample window of k max .
Despreader Architecture
FIG. 3 illustrates a despreader architecture for the despreading method described in the above embodiment. The shift registers, Z −1, s, have 128 unit delays and 64 taps. The taps are positioned at the inputs of every other register. The operation of the shift register starts when 64 incoming samples of the inputs of the received code r x occupy the first 64 shift registers. Each tap multiplies the value of the received sample being received in the shift register with a predetermined value related to the correlation code, C 128 where the predetermined value associated with the ith tap is the value of the (2 i−1)th correlation code sample. The despreading output sample, r c (k) with despreading output index k is calculated as the sum of the products of multiplication at all taps. After this computation, the data/samples are then shifted by one and the computation repeated. The data/samples will keep on shifting and the output of the addition tree is captured until the maximum of the absolute value of the despreading output is obtained. Whenever the maximum value of the output is captured, the index position of the sample in the shift register is recorded and that information will be used to determine k max and decide on the despread symbols as indicated in Equations 2 and 3. Using the unique feature of the differential encoded PN codes, if a received signal among the last 8 symbols is received, the output is a negative peak. Therefore, positive outputs map to the first 8 symbols while the negative peaks map to last 8 symbols. For example, where the maximum value of the output is positive and the index is among first 8 samples, then the despread symbol is Symbol number 0 (ZERO). If the maximum value happens among samples number 9 to sample number 16, the despread symbol is determined to be the Symbol 1 and so on.
With the superior properties of the new code set, the demapping algorithm is very easy to implement in hardware and is described in Equations 3 and 3a. In other embodiments where the alternate samples of the correlation code is not zero, taps can be inserted at the inputs of every shift register of the above-described despreader architecture so that the multiplication process is performed at all registers instead of every other register.
Symbol Timing Track
Sampling clock mismatch can reach as high as +/−40 ppm as allowed by the original PN codes. Therefore, if a transmitter has a +40 ppm sampling clock frequency error and a receiver has a −40 ppm sampling clock error, the total frequency error is 80 ppm. This sampling clock frequency mismatch between the transmitter and the receiver causes the sampling phases of the received signals to continually change, and, at times, some samples are dropped or repeated. As a result, at the receiver side, some mechanism has to be built to compensate and track the timing phase changes. In some applications, it is possible to remove the frequency error before despreading by using closed loop timing recovery circuits. However, the designs of these closed loop recovery circuits are difficult. They are power sensitive and require a lot of fine tuning making them expensive for many applications.
Embodiments of this invention do not require the use of closed loops since their inherent properties build in tolerances to sampling clock mismatch. Therefore, hardware implementation of this despreading method is much easier and cheaper. In generating the despreading correlation code from Symbol 0 of the differential encoded PN code, the last 4 samples of the correlation code is cyclicly shifted right such that, when there the incoming signals are perfect and there is no noise, the despreading output indexes for the 16 symbols start at 5 and are separated by 8. That is, for perfect incoming signals, the despreading output indexes are at 5, 13, 21, 29, 37, 45, 53, 61, 69, 77, 85, 93, 101, 109,117, and 125. The perfect symbol position for Symbol 0 is adjusted to occur at 5 to take into account that the timing drift can occur in both directions. With timing frequency offset, the peaks of the despreading outputs will move from those perfect positions because of the sampling phase offset. However, for short burst, these peaks do not move much with limited timing frequency offset.
For example, with the maximum timing frequency offset of 80 ppm in this embodiment with the longest burst of 127 bytes payload, the number of samples that can be moved with changes in the sampling phase is calculated to be:
80 e− 6*(1064/4*32*2)=1.3619 samples
where 80e−6 is the PPM value; 1064, i.e., (127*8+32+8+8), is the number of bits transmitted; the factor 4 accounts for the bits to symbol conversion; the factor 32 accounts for the spreading ratio; and the factor 2 is the up-sampling rate during despreading for the chips.
The outputs of the despreading output indexes are shown in FIG. 5 . The underlined numbers are assumed to be perfect signal position of the despreading output indexes. The phase offset will cause the despreading output indexes to shift from the perfect signal position. However, since perfect signal positions of the symbols are separated by 8, as long as the peak indexes do not move more than 3 samples, a correct decision on the symbol that is transmitted is still made. This is expressed in equations 3 and 3a with cover timing phase offset of ±3 samples. PN despreading is also robust if the PN code phase is within half chip interval since the correlation code derived from Symbol 0 are 2 times upsampled.
While the present invention has been described with reference to certain preferred embodiments, it is to be understood that the present invention is not limited to such specific embodiments. Rather, it is the inventor's contention that the invention be understood and construed in its broadest meaning as reflected by the following claims. Thus, these claims are to be understood as incorporating not only the preferred embodiments described herein but also all those other and further alterations and modifications as would be apparent to those of ordinary skilled in the art. | In a spread spectrum system, methods and despreader architectures for despreading the received spreaded codes with the use of a single correlator and a single correlation code is provided. Before despreading the incoming received spreaded codes, a single correlation code is generated using a symbol from a set of symbols that has been mapped into a set of differential encoded PN codes. Despreading output samples for each received spreaded code are obtained by correlating the received spreaded code with this single correlation code. Correlation is accomplished by multiplying each received sample of the received spreaded codes with the correlation code samples and accumulating the products of this multiplication. After correlation, the index for the maximum or minimum peak of the despreading output samples for each code is identified. This index can then be mapped into a symbol corresponding to the transmitted information. Corresponding despreader architectures comprise of a number of taps attached to a series of shift registers. Received samples of each received spreaded codes are inputted into the shift registers. The despreader architectures accumulates the products of multiplication of the value of the shift register with a predetermined value associated with each tap to produce the despreading output samples of a received spreaded code. It identifies the despreading output index producing the maximum of the absolute value of the despreading output and maps said index into a symbol corresponding to the transmitted information. | 7 |
BACKGROUND OF THE INVENTION
This invention relates to the utilization of advantages offered by an economizer cycle to provide effective continuous and gradual variability in the control of multiple operating parameters in a refrigerant system.
Refrigerant systems typically operate to provide heating or cooling for various applications. In a refrigerant cycle of a standard refrigerant system, a compressor compresses a refrigerant. The compressed refrigerant is delivered to a condenser, and from the condenser to an expansion valve. From the expansion valve the refrigerant is delivered to an evaporator, and then back to the compressor.
One way to improve efficiency of modern refrigerant cycles is the use of an economizer cycle. In the economizer cycle, a portion of the refrigerant is tapped downstream of the condenser, and passes through an auxiliary expansion device. Passing this tapped refrigerant through the auxiliary expansion device cools the refrigerant. The main flow of refrigerant is passed through an economizer heat exchanger along with this tapped cold expanded refrigerant. Thus, the main flow is cooled in the heat transfer interaction with this tapped refrigerant flow. This subcooled main refrigerant flow thus has a greater cooling capacity when it reaches the evaporator. A similar process, although generally reversed, can be utilized in heating mode for providing a similar economizer function. For purposes of this application, the invention will be described in a cooling mode, however, a worker of ordinary skill in the art will recognize its parallel application in a heating mode.
Generally, known economizer cycles have either been on or off to vary system capacity. The prior art has utilized a continuous modulation valve, located in the liquid region upstream of the economizer heat exchanger. However, this continuous modulation valve has not been utilized to achieve anything other than a preset superheat value of refrigerant entering the compressor or to flood the compressor with additional liquid refrigerant to cool the compressed vapor within the internal compression process.
The present invention recognizes that the use of an economizer circuit provides the refrigerant circuit designer with a good deal of flexibility and overall system control.
SUMMARY OF THE INVENTION
In the disclosed embodiment of this invention, the amount of refrigerant passing through the economizer tap is modulated, or varied, to achieve various control strategies. It is also known in the prior art to use an adjustable valve to maintain a preset superheat value of refrigerant entering the compressor either on the suction or economizer line to flood the compressor with additional liquid refrigerant to cool the compressed vapor within the internal compression process. Thus, the present invention achieves several control possibilities, by modulating the amount of refrigerant passed through the economizer circuit for the reasons other than maintaining preset superheat or flooding the compressor with liquid refrigerant.
A number of different control strategies can be developed by modulating the economizer cycle. Some specific examples, however, will now be given.
As one example, head pressure can be controlled. Head pressure control is important during operation in low ambient temperature environments. In the prior art, head pressure control has been achieved with some undesirable tradeoffs. However, by modulating the amount of economizer flow, gradual adjustment of the head pressure can be achieved with minimal effect on evaporator performance and overall system efficiency. Thus, should it be desired to control head pressure, the amount of fluid flowing through the liquid portion of the economizer tap line can be adjusted to achieve a gradual adjustment of head pressure. The economizer tap line can, for example, be provided with a variable expansion valve whose opening position can be modulated continuously from being fully open to being fully closed. This method can be employed on its own, or in addition to existing techniques for head pressure control, such as, for example, shutdown of the condenser fans.
Another control strategy deals with maintaining discharge temperature within acceptable limits. The discharge temperature control is critical for compressor reliability (discharge temperature should not exceed a certain specified value). Since the normally cooler economizer flow is combined with the partially compressed main refrigerant flow (inside the compressor) cooling the latter, management of the economizer superheat by modulation of the expansion device to other than a preset value can effectively control compressor discharge temperature, particularly at high pressure ratio condition or minimum refrigerant flow conditions. Also during a high mass flow operation through a condenser, it can be advantageous to reduce the amount of mass flow through the economizer branch of the system. In this case, the reduction in the mass flow through the economizer branch of the system by modulation of the expansion valve would result in a drop in discharge pressure. The drop in the discharge pressure would lead to reduction of the discharge temperature.
Also, at the maximum load conditions (primarily occurring in high ambient temperature environments) compressor power can be limited (by the motor strength or compressor structural limitations). In such circumstances, while the system capacity is needed the most, nuisance shutdowns may occur as the system would trip on internal system protection and customers lose all cooling. In such circumstances, it would be desirable to unload the compressor before the shutdown would occur, and the economizer flow modulation approach offers such an opportunity. Continuous reduction in the economizer flow rate limits the required compressor power and prevents such shutdowns from happening in the most efficient manner (in comparison to other unloading techniques, such as switching between economized and non-economized modes of operation or bypassing a portion of the refrigerant flow to the compressor suction port), since a shutdown threshold can be easily determined. Additionally, power grid load during the peak load times can also be minimized.
Furthermore, the undesirable accumulation of ice on the evaporator coils can be minimized, under certain conditions, by increasing the saturated temperature of the refrigerant flowing through the evaporator coil. The increase in the evaporator coil temperature is achieved by gradually unloading the evaporator coil by decreasing the amount of subcooling entering the evaporator. The amount of subcooling in turn is decreased by gradually decreasing the amount of the expansion valve opening.
One advantage of the above control strategies is that they can easily be applied to tandem compressors operating in parallel with each other and sharing common condenser, evaporator and economizer heat exchanger. In this case, a common expansion valve located downstream of the economizer heat exchanger will control the amount of flow in the economizer line that is shared by both compressors.
System efficiency and life-cycle cost are the two essential ingredients of the unit design and acceptance ion the market. These parameters can be noticeably improved by the economizer modulation technique, since the number of start-stop compressor cycles is significantly reduced. As a result, temperature control, humidity control and compressor reliability are also improved.
It should be noted that all the techniques outlined above could be selectively implemented for each circuit in the multiple circuit system, which would enhance the overall unit operation and control.
These and other features of the present invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiment. The drawings that accompany the detailed description can be briefly described as follows.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a refrigerant cycle incorporating the present invention.
FIG. 2 is a simplified flowchart of the basic invention.
FIG. 3 illustrates unit capacity variation with respect to the opening of an expansion device.
FIG. 4 is a schematic view of a refrigerant cycle incorporating the present invention for the case of two tandem compressors.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows a refrigerant cycle 20 having a compressor 22 delivering a refrigerant to a condenser 24 . From condenser 24 the refrigerant passes to a main expansion device 26 , and then to an evaporator 28 . As is known, a bypass valve 30 may provide communication between a suction line 31 , and an economizer return line 33 . Economizer shutoff valve 32 may be placed on the return line 33 . The refrigerant from the return line 33 enters the compressor 22 through intermediate port 44 . A tap line 34 branches of from a main refrigerant flow in line 36 leading to the main expansion device 26 . Tap line 34 passes through an auxiliary or economizer expansion device 38 . The tapped refrigerant, after having passed through the expansion device or valve 38 , passes through an economizer heat exchanger 40 along with the main refrigerant flow line 36 . While the tapped and main refrigerant flows are illustrated, for simplicity, flowing in a common direction, it is preferred that the two flows have a counter-flow arrangement. A control 42 controls the shut-off valve 32 and/or the expansion device 38 . It should be understood that the expansion device 38 is variably controllable. It should he understood that control 42 may be a conventional control although provided with the ability to perform additional control functions as will be disclosed below, and in particular controlling the expansion device 38 . Thus, and as the specific functions are mentioned below, it should be understood that the control would communicate with temperature sensors, pressure sensors, etc. as are known in the art to achieve the varying steps of control.
As disclosed in the flowchart of FIG. 2 , the control monitors a desired condition or state for a value of performance characteristic in the refrigerant system. If the control determines that a particular condition would be desirable, the amount of refrigerant passing through the economizer tap 34 may be modulated to achieve this desired state. A worker of ordinary skill in the art would recognize that by modulating the amount of refrigerant passing through the tap 34 a wide variety of controls can be achieved. As examples, some specific applications are disclosed, however, a worker of ordinary skill in the art would recognize that other control features can be achieved by modulating the economizer flow.
As one example, head pressure can be controlled. Head pressure control is important during operation in low ambient temperature environments. Control 42 modulates the amount of economizer flow, and gradual adjustment of the head pressure can be achieved with minimal effect on the evaporator performance and overall system efficiency. When control 42 determines it is desired to change head pressure, the amount of fluid flowing through the economizer tap line is adjusted to achieve a gradual adjustment of head pressure. This adjustment is made by controlling the amount of valve opening between completely open and completely closed. This method can be employed on its own, or in addition to existing techniques for head pressure control such as, for example, shutdown of the condenser fans.
By varying the amount of expansion device 38 opening, the compressor discharge temperature or refrigerant temperature entering the intermediate compression port can be controlled. The discharge or intermediate port temperature control is achieved by controlling the amount of economizer flow returned to the compressor through line 33 . Again, this control can be achieved gradually and through an infinite number of steps by control of expansion device 38 . Also, since there is a relationship between the amount of refrigerant passing through the intermediate compression port and the refrigerant temperature entering the economizer intermediate port, other system conditions affected by the refrigerant flow through the intermediate port can be controlled by assessing the changes in the refrigerant temperature entering the intermediate compression port.
Further, under certain conditions or operating parameters, and in particular high load conditions, compressor 22 and its motor may be approaching extreme conditions that otherwise might result in shutdown of the compressor due to overloading the motor. Such would be undesirable. Rather than shutting down the compressor due to motor overload, the modulation of the amount of economizer flow provides the ability to reduce the load on the motor, and thus potentially avoids the need to shut off the compressor. By reducing the amount of cycling, the life of the compressor can be extended, and its reliability can also be enhanced.
The variable shutoff of the expansion device also provides additional benefits in gradual capacity control by allowing the capacity to be varied without cycling the unit. FIG. 3 provides an illustration of how an operating condition, namely unit capacity, can be gradually controlled for a specific operating parameters by changing the amount of expansion device opening anywhere in the range from 0% to 100% opening. At 0% opening (the valve is shut off) and the unit capacity is at the lowest value. As the valve opening is increased, the unit capacity also gradually increases up to a maximum capacity reached at 100% opening (the valve is fully open). Similar graphs can also be developed for other operating conditions discussed above, such compressor discharge temperature, refrigerant temperature at the intermediate port, motor power draw, head pressure, etc.
Furthermore, the undesirable accumulation of ice on the evaporator coils can be minimized by increase in the evaporator coil temperature by gradually unloading the evaporator coil by decreasing the amount of subcooling entering the evaporator. The amount of subcooling in turn is decreased by gradually decreasing the amount of the expansion valve opening.
Advantages of the above control strategies are that they can easily be applied to tandem compressors operating in parallel with each other and sharing common condenser, evaporator and economizer heat exchanger. In this case, a common expansion valve located downstream of the economizer heat exchanger will control the amount of flow in the economizer line that is shared by both compressors. FIG. 4 illustrates this arrangement. In FIG. 4 , numeral references similar to FIG. 1 are utilized.
The control of the various features as mentioned above, and which are achieved by modulating the auxiliary expansion device, have been provided in the past by modulating other components of the refrigerant system. Thus, a worker of ordinary skill in the art would know how to modulate the auxiliary expansion device to achieve these functions. What is novel is using the auxiliary expansion device to achieve these functions Moreover, the feedback which is to be sent to the control 42 is generally known in the prior art, and a worker of ordinary skill in the art would recognize how to provide such feedback to the control 42 .
Although preferred embodiments of this invention have been disclosed, a worker of ordinary skill in the art would recognize that modifications would be within the scope of this invention. For that reason the following claims should be studied to determine the true scope and content of this invention. | A refrigerant cycle is provided with an economizer circuit. The amount of refrigerant passing through the economizer circuit can be gradually modulated by an expansion device whose position can be easily adjusted from fully open to fully closed or disengaged. In the past, economizer circuits have either been fully engaged or fully disengaged. Modulation of economizer flow allows for variable capacity operation. This improves unit operating efficiency, minimizes unit cycling and prevents compressor overloading at extreme of operating conditions. It also allows for head pressure and discharge temperature control. | 5 |
CROSS REFERENCES TO CO-PENDING APPLICATIONS
This patent application is a continuation-in-part of Ser. No. 08/484,072 entitled "Small Intracorneal Lens" filed on Jun. 7, 1995, which is a continuation of Ser. No. 08/026,597, entitled "Small Intracorneal Lens" filed on Mar. 5, 1993, by the same inventor, both now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is for an intracorneal lens, and more particularly, pertains to a small intracorneal lens with two regions of focality.
2. Description of the Prior Art
Three prior art patents, Choyce (U.S. Pat. No. 4,607,617), Grendahl (U.S. Pat. No. 4,624,669) and Lindstrom (U.S. Pat. No. 4,851,003), for intracorneal lenses describe large lenses or do not teach a bifocal or multifocal effect.
Barrett et al. (U.S. Pat. No. 5,196,026) describe a small intracorneal lens that does not significantly impede nutrient flow through the cornea and only involves a small optical region of the cornea. The region of cornea that surrounds the perimeter of the device of Barrett et al. is not optically affected by their lens. Barrett disclose a "bull's-eye" intracorneal lens that contains a hole drilled out of the center of the lens which will allow flow of nutrients through the cornea. One does not know from the Barrett et al. description if the aperture made in the lens should be a pin hole or if it should be large in comparison to the optical zone of the cornea. Barrett et al. teach a smaller lens that does not require an aperture and does not impede nutrient flow due to its small diameter size.
Shepard (U.S. Pat. No. 4,994,080) discloses a lens that has an aperture in it, but it is not suitable for an intracorneal inlay. Shepard describes an optical lens that has application for a contact lens, a corneal overlay, or as an artificial implanted lens replacement. The lens has at least one, but can contain several, small pin holes, which are referred to as stenopaeic openings. These openings are intended to pass only those light beams that are parallel to the central axis of the stenopaeic opening back onto the retinal portion of the eye. This method of light focusing through pin holes can be very limiting in terms of field of view and limits the size of image that can be adequately focused. It is furthermore doubtful that such a lens would have any application as an intracorneal inlay due to the anticipated growth of corneal stromal tissue into the pin hole of Shepard's device, thereby limiting its usefulness as an intracorneal lens.
The present intracorneal inlay device is designed to overcome the limitations of prior art devices and provide for multifocality.
The present invention overcomes the disadvantages of the prior art by providing a small intracorneal lens where the intracorneal lens provides two focal regions of specific configuration. The central region provides adequate area for imaging at one focal length, and the surrounding area provides imaging at a second focal length. The transition is designed to minimize distortion of the image.
SUMMARY OF THE INVENTION
The invention comprises an intracorneal lens that is inserted between stromal layers of the cornea and provides two distinct regions of focality. The primary embodiment discloses two distinct regions of the disc-shaped lens comprising a central region with a specific thinner wall thickness configuration and its associated focality and a surrounding region with a thicker wall thickness configuration and a second focality. The central region can be constructed such that it provides some optical correction to the central region or it can be made so that it provides no additional correction or change to the normal focal length provided by the cornea. The surface configuration for either the central or surrounding region on either the anterior or posterior side of the lens can be concave, convex or planar. The transition from the thinner central region to the thicker surrounding region can be made gradual to avoid edge effects that may distort the image. The transition can also consist of a sharp step change in thickness or it can be rounded. The entire lens can be constructed of a permeable material, such that oxygen and other nutrients can flow through the cornea at the lens implant site. The central region can be constructed from a material of different refractive index from that of the surrounding region. The central region can be configured such that the thickness is completely reduced to zero providing an open central region with a focality provided entirely by the natural cornea.
Having thus described embodiments of the present invention, it is the principal object of the present invention to provide an intracorneal lens which provides two regions of focality.
One object of the present invention is to provide a small intracorneal lens where the cornea, along with the central region of the lens, provides one focal plane, and the surrounding region of the intracorneal lens and the cornea provides a second focal plane. The central region is contiguous with the surrounding region forming a transition region between them that does not distort the image due to edge effects. The central region can have a thinner lens configuration than the surrounding region, and the surfaces of either the central region or the surrounding region can be either convex, concave or planar. The diameter of the central region can range from 1.0 to 2.5 mm, with a preferable diameter of 1.5 to 2.0 mm. The diameter of the surrounding region can range from 2.5 to 4.5 mm, with a preferable diameter of 3.0 to 4.0 mm. A similar bifocal or multifocal effect can also occur with the use of a single lens structure with one focality occurring through the lens and another focality occurring around the lens and through the cornea alone. This is not the intent of the present invention which provides bifocality from the central and surrounding regions of the present lens in combination with the cornea. The present lens can be used to form three regions of focality wherein two focal regions are provided by the central and surrounding regions of the present lens in combination with the cornea, and a third region of focality is formed in the region of the cornea surrounding the lens. The three regions of focality could be used to provide near, middle and far range of vision, for example.
Another object of the present invention is a small intracorneal lens in which the cornea alone provides for one focal plane in the central region, and the surrounding region of the lens with the cornea provides a second focal plane. Here the thickness of the lens in the central region has been reduced to zero and eliminated. Consideration of edge effects at the transition between central and surrounding regions and the diameters of the central region and the surrounding region are the same as described in the first object of the present invention.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects of the present invention and many of the attendant advantages of the present invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings, in which like reference numerals designate like parts throughout the figures thereof and wherein:
FIG. 1 illustrates a plan view of a small intracorneal lens;
FIG. 2 illustrates a cross-sectional view of the small intracorneal lens taken along line 2--2 of FIG. 1;
FIG. 3 illustrates a plan view of a first alternative embodiment of a small intracorneal lens;
FIG. 4 illustrates a cross-sectional view of the first alternative embodiment taken along line 4--4 of FIG. 3; and,
FIG. 5 illustrates a cross-sectional view of a second alternative embodiment of a small intracorneal lens.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
An intracorneal lens with bifocality is needed to provide those patients with myopia, presbyopia, hyperopia or other visual ailments of the eye an opportunity to image objects both near and far using different regions of the intracorneal lens in combination with their natural cornea. In the current invention, the central region of the lens is configured with an optical surface with a specific wall thickness configuration. Generally, the wall thickness configuration of the central region is thinner than the wall thickness configuration of the surrounding region of the lens, although this is not a requirement. The central region wall thickness configuration can also be such that lens material is completely absent from the central region of the intracorneal lens. The central region is contiguously joined to the surrounding region by a transition region. The thickness configuration of the transition region provides minimal distortion to the image due to edge effects that can occur at the edge of or within the transition region.
The patient with such a bifocal intracorneal lens can view an object at one focal length using the focality provided by the central region of the lens plus the cornea and can view an object at a second focal length using the focality provided by the surrounding region of the lens plus the cornea. Either the central region or the surrounding region can provide a greater or lesser focal length than the other region. This is achieved by altering the surface geometry of the intracorneal lens in the central region and the surrounding region independently. Considering that the normal cornea has a convex/concave outer and inner surface geometry, respectively, the intracorneal lens can have a surface geometry for either the central region or the surrounding region and for either the anterior or posterior surface that is either convex, concave or forms a planar surface. The amount of concavity and convexity can also be modified within the geometrical constraints of the human eye anatomy and can have more or less geometrical convexity or concavity than that found in the normal cornea.
The intracorneal lens can also provide for yet a third region for focality around the outside of the surrounding region.
The small intracorneal lens 30 is to treat low hyperopia and myopia. The powers of the lens can range from -0.50 diopters to -10 diopters and +0.50 diopters to +10 diopters. One purpose is for low corrections, particularly -0.50 to -5 diopters to +0.50 to +5 diopters. Especially, the small intracorneal lens can be used for the correction of presbyopia. The lens has two regions of different focal length, thereby providing two different corrections, one for the central region and another for the surrounding region.
FIGS. 1 and 2 illustrate a small intracorneal lens 30 with a central region 10 having a central diameter 18 that can range from 1.0 to 2.5 mm but preferably is from 1.5 to 2.0 mm. This diameter is large enough to allow adequate passage of light to form a usable image on the retina. The surrounding region 12 has an outer diameter 16 that ranges from 2.5 to 4.5 mm but preferably ranges from 3.0 to 4.0 mm. The transition region 14 is contiguous with the central region and the surrounding region and has a transition width 20 that ranges from zero to 1.0 mm but preferably ranges from 0.1 to 0.5 mm. The central region 10 has an outer surface 22 and an inner surface 24 either of which can be concave, convex or planar. In FIG. 2, the outer surface 22 is shown to be concave and the inner surface 24 is shown to be planar. The surrounding region 12 of the lens has an outer surface 26 and an inner surface 28 either of which can be concave, convex or planar. As shown in FIG. 2, the outer surface 26 is convex and the inner surface 28 is concave. The amount of convexity and concavity for the inner surface or outer surface can differ from each other and can vary depending upon the optical needs of the patient. This lens, for example, could be used to treat a patient with hyperopia wherein the central region makes only slight correction for distant vision and the surrounding region corrects optically for close vision. Alternately, the lens can be used to correct for myopia vision with bifocality occurring between the central region and the surrounding region. The lens can allow corrections of up to positive 10 diopters or negative 10 diopters depending upon the configurations of the lens surfaces and the thickness of the lens. The thickness 32 of the surrounding region 12 can range from 0.1 to 1 mm, with a preferred thickness of 0.3 to 0.6 mm. The thickness 34 of the central region 10 can range from zero to 1 mm, with a preferred thickness of 0.2 to 0.5 mm. The small intracorneal lens can be constructed from a suitable material such as PMMA, polycarbonate, polysulfone, hydrogel, silicone or other polymer material. The outer edge of the surrounding region is rounded and smooth.
FIGS. 3 and 4 illustrate a first alternative embodiment of the intracorneal lens, labeled 30a, with all other numbers indicative of the same lens components and dimensions as found in FIGS. 1 and 2. Here the transition region 14 has been omitted and an abrupt transition is shown without gradual tapering from the central region 10 to the surrounding region 12, although tapering could occur between regions. Here the central region 10 is shown with a convex outer surface 22 and a concave inner surface 24. The surface configuration for the inner or outer surface can be convex, concave or planar. The central region 10 can be constructed of a material of the same refraction properties as that of the surrounding region 12 or it can be made form a material of different refractive index. The central region 10 can also be omitted, thereby providing an open aperture and refractive index representative of the cornea alone, as illustrated in FIG. 5, next described.
FIG. 5 illustrates a second alternative embodiment of the intracorneal lens, labeled 30b, with the central region 10 omitted, thereby providing an open circular aperture 10a for providing an optical focality derived solely from the cornea alone. All other numerals in FIG. 5 are indicative of the same lens components and dimensions as found in the other drawing figures and as previously described.
Various modifications can be made to the present invention without departing from the apparent scope hereof. | An intracorneal lens that is inserted between stromal layer of a cornea of an eye, and provides two distinct regions of focality. The lens includes a central region with a thinner wall and a surrounding region with a thicker wall. | 0 |
TECHNICAL FIELD OF THE INVENTION
[0001] This invention relates in general to high-frequency circuits and, more particularly, to high-frequency circuits which utilize a pulse with a very narrow width.
BACKGROUND OF THE INVENTION
[0002] In high-frequency circuits, there is often a need for a pulse having a very narrow width. As one example, there are low-noise, phase-locked microwave oscillators which effect phase sampling with a solid-state phase detector. In a known system, the sampling phase detector uses a step recovery diode (SRD) to generate a pulse which has a fairly narrow width, and which is used to clock a diode bridge mixer-phase detector. In particular, the voltage across the SRD is differentiated, in order to generate a pulse that corresponds to a time interval when the SRD voltage has a fairly high slew rate. Although circuits of this type have been generally adequate for their intended purposes, they have not been satisfactory in all respects.
[0003] More specifically, the narrow pulses generated by differentiating an SRD voltage have a width of approximately 22 to 50 picoseconds. While this is sufficiently narrow for many systems, there are other systems which operate at very high frequencies, where even this narrow pulse width is too large, and can produce undesirable effects such as jitter, and/or limits on the gain-bandwidth product.
SUMMARY OF THE INVENTION
[0004] From the foregoing, it may be appreciated that a need has arisen for a method and apparatus which avoid at least some of the disadvantages of pre-existing techniques. According to one form of the invention, a method and apparatus are provided to address this need, and involve: providing a circuit having a first portion which includes a resonant tunneling device, and a second portion which includes a differentiator; applying to the first portion an input signal; causing the resonant tunneling device to respond to the input signal by effecting a quantum jump in magnitude of an electrical signal characteristic from a first value to a second value, the second value being substantially different from the first value, and the quantum jump in magnitude from the first value to the second value taking an interval of time; and causing the differentiator to respond to the quantum jump of the electrical signal characteristic from the first value to the second value by producing a narrow pulse having a duration which is approximately equal to the interval of time.
[0005] A different form of the invention involves: providing a circuit having a first portion which includes a resonant tunneling device, and a second portion which includes a sampling portion with a sampling input; applying to the first portion an input signal; applying to the sampling input a signal to be sampled; causing the resonant tunneling device to respond to the input signal by effecting a quantum jump in magnitude of an electrical signal characteristic from a first value to a second value, the second value being substantially different from the first value, and the quantum jump in magnitude from the first value to the second value taking an interval of time; and causing the sampling portion to respond to the quantum jump in magnitude of the electrical signal characteristic from the first value to the second value by sampling the signal at the sampling input during a time period which is approximately equal in duration to the interval of time.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] A better understanding of the present invention will be realized from the detailed description which follows, taken in conjunction with the accompanying drawings, in which:
[0007] FIG. 1 is a schematic circuit diagram of an apparatus which is a sampling phase detector circuit that embodies aspects of the present invention;
[0008] FIG. 2 is a graph of a curve that shows how a current flowing through a resonant tunneling diode in the embodiment of FIG. 1 will vary in response to variation of a voltage applied across it;
[0009] FIG. 3 depicts two related graphs, the upper graph showing how the voltage across the resonant tunneling diode will vary over time as the current through it is progressively increased and then progressively decreased, and the lower graph showing an output voltage that a differentiating portion of the circuit of FIG. 1 will produce over time in response to the voltage shown in the upper graph;
[0010] FIG. 4 is a schematic circuit diagram of an apparatus which is an alternative embodiment of the apparatus of FIG. 1 , and which embodies aspects of the present invention;
[0011] FIG. 5 is a schematic circuit diagram of an apparatus which is another alternative embodiment of the apparatus of FIG. 1 , and which embodies aspects of the present invention;
[0012] FIG. 6 is a graph which depicts a power spectral density in relation to frequency of an output of a resonant tunneling diode in the embodiment of FIG. 5 ;
[0013] FIG. 7 is a schematic circuit diagram of an apparatus which is still another alternative embodiment of the apparatus of FIG. 1 , and which embodies aspects of the present invention; and
[0014] FIG. 8 is a schematic circuit diagram of an apparatus which is yet another alternative embodiment of the apparatus of FIG. 1 , and which embodies aspects of the present invention.
DETAILED DESCRIPTION
[0015] FIG. 1 is a schematic diagram of an apparatus which is a sampling phase detector circuit 10 . The circuit 10 includes an input portion 12 , a differentiating portion 13 , and a sampling portion 14 . The circuit 10 has a reference input defined by a pair of terminals 16 and 17 in the input portion 12 , a sample input defined by a pair of terminals 18 and 19 in the sampling portion 14 , and an output defined by a pair of terminals 21 and 22 in the sampling portion 14 .
[0016] The input portion 12 includes a transformer 26 with an input coil 27 and an output coil 28 . The ends of the input coil 27 are each coupled to a respective one of the input terminals 16 and 17 , and the input terminal 17 is also coupled to ground. The input portion 12 includes a resonant tunneling diode (RTD) 31 of a known type, which is coupled between two nodes 32 and 33 of the circuit. The ends of the output coil 28 of the transformer 26 are each coupled to a respective one of the two nodes 32 and 33 . The input portion 12 also includes a resistor 36 and a capacitor 37 , which are coupled in parallel between the node 32 and ground, and a resistor 38 and a capacitor 39 , which are coupled in parallel between the node 33 and ground. The resistors 36 and 38 are substantially equivalent, and the capacitors 37 and 39 are substantially equivalent.
[0017] The differentiating portion 13 has two capacitors 46 and 47 , which are substantially equivalent, and which effectively serve as a differentiator. The capacitor 46 has one end coupled to the node 32 , and its opposite end coupled to a node 48 . The capacitor 47 has one end coupled to the node 33 , and its opposite end coupled to a node 49 .
[0018] The sampling portion 14 includes two Schottky diodes 51 and 52 , which are equivalent. The diodes 51 and 52 are coupled in series between the nodes 48 and 49 , and a further node 56 is defined between the diodes 51 and 52 . The diodes 51 and 52 are oriented so that the cathode of diode 51 is coupled to the node 48 , and the anode of diode 52 is coupled to the node 49 . The sampling portion 14 has three resistors 61 - 63 which are coupled in series with each other between the nodes 48 and 49 . The resistors 61 and 63 have substantially the same resistance. The resistor 62 is a variable trim resistor, with a slider coupled to the terminal 22 of the output. The resistor 62 can be adjusted so as to maintain balance within the illustrated circuit.
[0019] In the sampling portion 14 , the terminal 18 of the sample input is coupled to ground. A capacitor 71 is coupled between the node 56 and the terminal 19 of the sample input. A resistor 72 is coupled between the node 56 and the terminal 21 of the output, and a capacitor 73 is coupled between the terminal 21 and ground.
[0020] The RTD 31 is a device of a known type, with operational characteristics which are known in the art. Nevertheless, to facilitate an understanding of the present invention, the operational characteristics of the RTD 31 are discussed briefly here.
[0021] FIG. 2 is a graph of a curve that shows how a current flowing through the RTD 31 will vary in response to variation of a voltage applied across the RTD 31 . It will be noted that the current has a resonant peak at 81 , and has a further and larger resonant peak at 82 , which is not visible in its entirety in FIG. 2 . There is a valley 83 between the two peaks 81 and 82 .
[0022] Although the curve in FIG. 2 can be viewed as a representation of how current varies as a function of a variation in voltage, it can conversely be viewed as a representation of how voltage varies as a function of a variation in current. In this regard, it will be noted that, as the current through the RTD is progressively increased to a value of I 1 from a value of zero, the voltage progressively increases to a value of V 1 from a value of zero, as indicated diagrammatically at 86 .
[0023] Then, as soon as the current exceeds I 1 the voltage suddenly makes a quantum jump at 87 from a value of V 1 at the top of the resonant peak 81 to a value of V 2 at a point along the leading edge of the resonant peak 82 . As is known in the art, this significant change in voltage from V 1 to V 2 occurs extremely rapidly, for example as fast as 1.5 to 2.0 picoseconds. Then, as the current continues to progressively increase above I 1 , the voltage progressively increases above V 2 , as indicated diagrammatically at 88 .
[0024] Assume that the current is thereafter progressively decreased. The voltage also progressively decreases, as indicated diagrammatically at 91 . The decreasing current eventually reaches a value of I 2 , which corresponds to a voltage V 3 . As soon as the current is decreased below the value I 2 , then the voltage very rapidly makes a quantum jump at 92 from the voltage V 3 to the voltage V 4 , and then continues to progressively decrease, as indicated at 93 . The change at 92 from the voltage V 3 to the voltage V 4 occurs very rapidly, for example in about 1.5 to 2.0 picoseconds. The time intervals of 1.5 to 2.0 picoseconds mentioned above are typical time intervals, but both are determined by the structural configuration of the RTD, and either or both can be varied by adjusting the structural configuration of the RTD.
[0025] The curve shown in FIG. 2 represents a relationship between a positive current and a positive voltage for the RTD 31 . For a negative current and negative voltage, and as is known in the art, there is a similar curve for the RTD 31 , which is a mirror image of the curve shown in FIG. 2 , reflected about the origin point at the intersection of the two axes.
[0026] During normal operation, a reference voltage V REF is applied between the input terminals 16 and 17 . For purposes of the present discussion, this input signal is assumed to be a sine wave, but it could alternatively be some other type of waveform. The transformer 26 responds to this input signal by causing a current to flow through the RTD 31 , where the variation in current flow through the RTD conforms to a sine function.
[0027] FIG. 3 shows two related graphs. The upper graph shows an example of how the voltage across the RTD 31 varies over time, as the current through the RTD 31 is first progressively increased, and then progressively decreased. In this regard, the curve shown in FIG. 3 has segments 106 - 108 and 111 - 113 , which respectively correspond to 86 - 88 and 91 - 93 in FIG. 2 . For clarity in the present discussion, the curve segments 106 , 108 , 111 and 113 are assumed to correspond to portions of the sine wave where the rate of change is relatively constant, and they are therefore shown in FIG. 3 as straight lines.
[0028] The curve segment 107 represents the rapid quantum jump in voltage from V 1 to V 2 , and the curve segment 112 represents the rapid quantum drop in voltage from V 3 to V 4 . As discussed above, it is an inherent characteristic of the RTD 31 that the voltage changes at 107 and 112 each occur very rapidly, for example in about 1.5 to 2.0 picoseconds. The voltage across the RTD 31 , such as that shown in the upper graph in FIG. 3 , serves as the input to the differentiating portion 13 in the circuit of FIG. 1 , which includes the capacitors 46 and 47 .
[0029] The lower graph in FIG. 3 shows the output voltage that the differentiating portion 13 will produce over time between the nodes 48 and 49 , in response to the voltage shown in the upper graph in FIG. 3 . In effect, the curve shown in the lower graph of FIG. 3 represents the derivative of the curve shown in the upper graph of FIG. 3 . It will be noted that the rapid voltage change at 107 in the upper graph produces a large positive pulse 121 of very narrow width, and the voltage change at 112 produces a large negative pulse 122 of very narrow width. In the disclosed embodiment, the widths 123 and 124 of the pulses 121 and 122 are each in the range of approximately 1.5 to 2.0 picoseconds, for example about 1.7 picoseconds. Due to the polarity of the diodes 51 and 52 , the diodes recognize one of the pulses 121 and 122 and ignore the other thereof, such that only one of these pulses actually appears at the node 56 which is located between the diodes 51 and 52 .
[0030] A signal which is to be sampled is applied between the terminals 18 - 19 of the sample input, and is referred to here as V SAMPLE . This signal is an alternating current (AC) signal, and is applied to the storage capacitor 73 through the coupling capacitor 71 and the resistor 72 . The voltage across the storage capacitor 73 determines the output voltage V OUT at the output terminals 21 - 22 . When the node 56 receives a large and narrow pulse from the differentiating portion 13 through the diodes 51 and 52 , the diodes 51 and 52 effectively couple in the load resistors 61 - 63 , SO that a portion of the energy introduced at the sample input 18 - 19 is absorbed in the load resistors 61 - 63 . This deprives the storage capacitor 73 of a portion of the charge that would otherwise end up on the capacitor 73 . Consequently, the pulse from the differentiating portion 13 causes the output voltage V OUT to be different than it otherwise would have been, which represents a form of sampling of the sample signal V SAMPLE during the time duration of the narrow pulse received from differentiating portion 13 .
[0031] FIG. 4 is a schematic diagram of an apparatus 140 , which is an alternative embodiment of the apparatus 10 of FIG. 1 . The apparatus 140 includes an input portion 142 which is different from the input portion 12 of FIG. 1 , and also includes a differentiating portion 13 and a not-illustrated sampling portion which are respectively identical to the differentiating portion 13 and the sampling portion 14 of FIG. 1 . In FIGS. 1 and 4 , equivalent parts are identified with the same reference numerals, and the following discussion addresses the differences between these embodiments.
[0032] The input portion 142 in FIG. 4 includes the input terminals 16 and 17 of the reference input, and also includes the RTD 31 . The input portion 142 has two terminals 146 and 147 , to which are applied respective direct current (DC) bias voltages +V and −V, which are equal and opposite in magnitude. A field effect transistor (FET) 148 has its source coupled to the terminal 146 , and its drain coupled to one end of a resistor 149 . The other end of the resistor 149 is coupled to the node 32 between the capacitor 46 and the RTD 31 . The gate of the FET 148 is coupled to the node 32 .
[0033] A further field effect transistor (FET) 151 has its source coupled to the node 33 between the capacitor 47 and RTD 31 , and its drain coupled to one end of a resistor 152 . The other end of the resistor 152 is coupled to the terminal 147 . The gate of the FET is coupled to the terminal 16 . In the embodiment of FIG. 4 , the FETs 148 and 151 are equivalent, and the resistors 149 and 152 have the same resistance. The FET 148 and resistor 149 effectively serve as a current source, and the FET 151 and the resistor 152 effectively serve as a current sink.
[0034] A reference signal is applied to the reference input terminals 16 - 17 , in the form of a voltage which causes dynamic variation in the conductivity of the FET 151 , thereby effecting dynamic variation of the amount of current flowing through the FET 148 , the resistor 149 , the RTD 31 , the FET 151 , and the resistor 152 . Thus, the voltage at the terminals 16 - 17 is effectively converted into a varying current through the RTD 31 , which causes the RTD 31 to produce a voltage between the nodes 32 and 33 which is similar to the voltage shown in the upper graph of FIG. 3 . The differentiating portion 13 and not-illustrated sampling portion of the embodiment of FIG. 4 operate the same as their counterparts in the embodiment of FIG. 1 , and are therefore not described here in detail.
[0035] FIG. 5 is a schematic diagram of an apparatus 160 which is another alternative embodiment of the apparatus 10 of FIG. 1 . The apparatus 160 includes an input portion 162 which is different from the input portion 12 of FIG. 1 , and also includes a differentiating portion 13 and a not-illustrated sampling portion which are respectively identical to the differentiating portion 13 and the sampling portion 14 of FIG. 1 . In FIGS. 1 and 5 , equivalent parts are identified with the same reference numerals, and the following discussion addresses the differences between these embodiments.
[0036] In the input portion 162 of FIG. 5 , the node 33 between the RTD 31 and the capacitor 47 is coupled to one end of a resistor 164 , and the other end of the resistor 164 is coupled to ground. A resistor 166 has one end coupled to the node 32 between the capacitor 46 and the RTD 31 , and its other end coupled to a node 167 . The resistors 164 and 166 have the same resistance. The FET 151 has its source coupled to the terminal 146 , its drain coupled to the node 167 , and its gate coupled to the terminal 16 . The terminal 17 is coupled to ground. A further FET 171 has its source coupled to the node 167 , its drain coupled to the terminal 147 , and its gate coupled to its own drain. The FET 171 is equivalent to the FET 151 . The FET 171 serves as a form of constant current source, which operates substantially independently of changes in the voltage applied across it. Since the current flowing through the FET 171 is constant but the current flowing through the FET 151 is not, variation of the current through the FET 151 operates through the resistor 166 to vary the current flowing through the RTD 131 .
[0037] As in the input portions of the other embodiments discussed above, the circuitry of the input portion 162 takes the voltage of the reference signal applied at the terminals 16 - 17 of the reference input, and converts it into a corresponding current flow through the RTD 31 . This causes the RTD 31 to generate between the nodes 32 and 33 a voltage comparable to that shown in the upper graph of FIG. 3 . The differentiating portion 13 and the not-illustrated sampling portion of the embodiment 160 operate in the same manner as their counterparts in the embodiment of FIG. 1 , and their operation is therefore not described here in detail.
[0038] FIG. 6 is a graph which depicts an operational characteristic of the circuit of FIG. 5 . In particular, FIG. 6 shows the power spectral density of the output of the RTD 151 (vertical axis), in relation to frequency (horizontal axis). This characteristic is determined mathematically by multiplying the Fourier transform of the voltage across the RTD by its complex conjugate. The units along the X-axis represent frequency/200 MHz. The units along the Y-axis are dBc, or in other words Decibels relative to the power in the input carrier to the circuit. The curve of FIG. 6 corresponds to application of a 10 GHz sine wave to the input of the FET 151 . The two FETs 151 abd 171 serve as a non-inverting buffer of this signal, and the buffered output is applied to the resistor 166 . The resistor 166 converts this voltage into a current, which is used as a sinusodial bias current to the RTD.
[0039] As evident from FIG. 6 , the effective output of the RTD is rich in harmonics, up to and above 200 GHz. In particular, these harmonics are seen in the plot as strong, discrete peaks in the power spectral density at various frequencies. Peaks are visible at the fundamental frequency (10 GHz), and at even and odd harmonics up to 190 GHz. Actually, the slow drop in spectral power with increasing frequency shows that the RTD waveform provides a very narrow pulse that will approximate an ideal impulse generator, running at the frequency of the input (which in this example case is 10 GHz). The harmonics are desirable for certain applications, for example where a circuit of the type shown in FIG. 5 is used as part of a low noise, phase-locked microwave oscillator. The harmonics permit phase lock to be accurately and reliably achieved at frequencies which are multiples of the fundamental frequency.
[0040] FIG. 7 is a schematic diagram of an apparatus 180 , which is still another alternative embodiment of the apparatus 10 of FIG. 1 . The apparatus 180 includes an input portion 182 , which is different from the input portion 12 of FIG. 1 , and also includes a differentiating portion 13 and a not-illustrated sampling portion, which are respectively identical to the differentiating portion 13 and the sampling portion 14 of FIG. 1 . IN FIGS. 1 and 7 , equivalent parts are identified with the same reference numerals, and the following discussion addresses the differences between these embodiments.
[0041] In the input portion 182 of FIG. 7 , a reference input defined by terminals 186 and 187 is provided in place of the reference input terminals 16 - 17 of FIG. 1 . The reference input voltage V REF is applied to the terminal 186 , and its complement is applied to the terminal 187 .
[0042] A resistor 191 has a first end coupled to the node 33 between the capacitor 47 and the RTD 31 , and has its other end coupled to the terminal 187 . An additional RTD 192 has one end coupled to the node 32 between the capacitor 46 and the RTD 31 , and has its other end coupled to one end of a resistor 193 . The other end of the resistor 193 is coupled to the terminal 186 . A reference current source 196 is coupled between the node 32 and ground. The RTDs 31 and 192 are equivalent, and the resistors 191 and 193 are equivalent.
[0043] Like the input portions of the other embodiments described above, the input portion 182 takes the reference input signal and converts it into a corresponding current flow through the RTD 31 , so that the RTD 31 produces between the nodes 32 - 33 a voltage of the type shown in the upper graph of FIG. 3 . The differentiating portion 13 and the not-illustrated sampling portion of the apparatus 180 operate in the same manner as their counterparts in the apparatus 10 of FIG. 1 , and their operation is therefore not discussed here in detail.
[0044] FIG. 8 is a schematic diagram of an apparatus 210 , which is an alternative embodiment of the apparatus 10 of FIG. 1 . The apparatus 210 includes an input portion 212 which is different from the input portion 12 of FIG. 1 , and also includes a differentiating portion 13 and a not-illustrated sampling portion which are respectively identical to the differentiating portion 13 and the sampling portion 14 of FIG. 1 . In FIGS. 1 and 8 , equivalent parts are identified with the same reference numerals, and the following discussion addresses the differences between these embodiments.
[0045] In the input portion 212 , the input terminals 16 - 17 and the transformer 26 of FIG. 1 have been replaced with a photodiode 216 and a light source 218 . The photodiode 216 is a component of a known type, such as a PIN photodiode or a metal-semiconductor-metal (MSM) photodiode. The photodiode has its anode coupled to the node 32 , and its cathode coupled to the node 33 . The light source 218 is a periodic pulsed laser of a type known in the art, such as a mode-locked laser, or a fiber-ring laser. Alternatively, the light source 218 could be a continuous laser with a mechanical shutter, or some other device that produces a periodic optical signal. The light source 12 outputs a varying optical signal 221 , which serves as a clock signal that varies in a periodic manner. The optical clock signal 221 causes the photodiode 216 to alternate between conducting and non-conducting states. When the photodiode is in its conducting state, it effectively creates an electrical short across the RTD 31 , so that the voltage across the RTD 31 is very low or zero. When the photodiode switches to its non-conducting state, current from the bias arrangement will cause a current to develop throught the RTD 31 , and the voltage across the RTD 31 will under a quantum jump such as that shown at 87 in FIG. 2 . In other respects, the operation of the circuit of FIG. 8 is generally similar to the operation of the circuit 10 of FIG. 1 , and is therefore not described here in further detail.
[0046] The present invention provides a number of advantages. One such advantage results from the generation of a pulse of very narrow width through use of a resonant tuning diode with a high slew rate, where the slew rate is on the order of about 3 picoseconds per volt. This is five to ten times faster than the slew rate of the step recovery diodes (SRDs) used in pre-existing systems. Therefore, when the voltage across the RTD is differentiated, the result is a pulse with a very narrow width, which can be as much as {fraction (1/35)} of the width of the typical pulse produced in pre-existing systems using SRDs. The ability to generate a very narrow pulse is advantageous in a variety of applications. As one example, when used in the context of a very fast sampling phase detector for a low-noise phase-locked microwave oscillator, the narrow pulse provides more accurate sampling, along with a reduction in jitter and an increase in bandwidth, where the bandwidth can be as much as five to ten times better than in comparable pre-existing systems which utilize SRDs. By using an RTD to generate a narrow pulse, sampling can occur at frequencies of 100 GHz to 200 Ghz, which was not possible with the wider pulses generated in pre-existing systems using SRDs.
[0047] Although several selected embodiments have been illustrated and described in detail, it will be understood that various substitutions and alterations can be made without departing from the scope of the present invention. That is, the depicted circuits are merely exemplary, and it is possible to add, delete, and/or rearrange components, or to utilize different circuit configurations, while still realizing the present invention. Other substitutions and alterations are also possible without departing from the spirit and scope of the present invention, as defined by the following claims. | A circuit includes a resonant tunneling device which is responsive to an input signal for causing an electrical signal characteristic to undergo a quantum jump in magnitude that takes an interval of time. According to one feature, a differentiator responds to the quantum jump in magnitude by producing a narrow pulse with a duration which is approximately the interval of time. According to a different feature, a sampling portion responds to the quantum jump in magnitude by sampling a signal during a time period having a duration which is approximately the interval of time. | 1 |
FIELD OF THE INVENTION
[0001] The present invention relates to a tool for optimising airplane flight trajectories and visualising the optimised trajectories in quasi real time.
BACKGROUND OF THE INVENTION
[0002] The operation of current commercial aircraft is highly automated, with the mission and trajectories flown being managed by a Flight Management System (FMS). Consequently, FMSs are programmed with flight plans generated by the aircraft operator, one of which will be chosen, adapted or input directly by the crew to be flown by the aircraft for the particular flight. The flight plans will normally have been designed in a manner to be advantageous to the aircraft operator from an economic perspective. Parameters such as climb, cruise and descent speeds, as well as operating altitudes, define the time of flight and fuel burn on the particular mission and these parameters are usually selected according to operational costs and other constraints (such as aircraft scheduling) in order to accommodate the aircraft operator's interests and needs. The flight plan will normally be submitted to the relevant Air Navigation Service Provider (ANSP) and is agreed upon prior to the start of the mission.
[0003] An aircraft, however, rarely flies according to the agreed flight plan without any alterations. This is because tactical variations from the flight plan invariably occur. Such variations may be due to factors such as operational delays, changes in aircraft operating weight, variations in weather conditions and new air traffic constraints. Factors such as delays, weight, ATC constraints and winds normally effect the vertical profile of a flight plan, resulting in changes in the aircraft's speed and altitude schedules, whilst air traffic constraints and bad weather often also result in deviations in the plan path flown.
[0004] Tactical deviations from the flight plan often result in a penalty in terms of fuel burn, emissions and operating costs. The penalties arise from limitations in current technology and practice.
[0005] Airline operators often use what is referred to as the Cost Index (CI) to establish the preferred operating point (speed, time of flight and thus trip fuel burn) of a particular flight. The CI is an arbitrary parameter that relates time-related costs with fuel costs. By selecting a particular CI, the operator will be selecting the time of flight and one programmed in the FMS, the system will schedule the operating speeds and altitudes according to the operating weight and reported winds and temperatures entered into it. Due to the nature of the concept, the CI is often set for a particular flight or group of flights and is often not altered during their progress. This, naturally, may result in the aircraft effectively being flown less efficiently than possible.
[0006] Whilst the CI is a useful tool that allows the operator to select advantageous operating points of the aircraft, current methods that generate flight profiles based on this concept are limited in their ability to identify the most advantageous flight profiles that need to be flown in the prevailing conditions operating conditions. This is due to a number of factors, including the limited processing power on current technology flight management systems, which results in methods used being simple and approximate in nature.
[0007] Air Traffic Control (ATC) constraints may also introduce operational and cost penalties. ATC is primarily concerned with ensuring safe separation between aircraft and, accordingly, issue tactical instructions that constrain the flight path of aircraft when this is necessary. While ATC may be sensitive to expeditious routing, it does not explicitly take the operational costs of airlines into account. Tactical instructions, such as lateral deviations in the planned path and speed and altitude constraints are issued that, with current technology, do not allow sufficient time for the re-planning of the flight by the aircraft operator or pilot in a way to reduce the impact of these instructions on the operating costs of the flight.
SUMMARY OF THE PRESENT INVENTION
[0008] From a performance perspective, it is understood that by improving the planning of a flight, at both strategic and tactical levels, significant reductions of fuel burn and emissions can be achieved, the former of the order of several percentage points over current levels.
[0009] Current operating practices and supporting technology, therefore, can be considered unsatisfactory and need to be complemented by a means that can enable better selection of flight trajectories and operating points for specific flight conditions at both tactical and strategic levels, thus allowing the aircraft to be flown more advantageously in terms of a selected criterion (such as cost) or criteria. The present invention is intended to mitigate at least some of the difficulties associated with current systems and practices.
[0010] Accordingly, the present invention, discloses a method and system that generates data pertaining to flight trajectories that are optimized according to one or a plurality of criteria (also referred to as objectives) whilst taking into account up-to-date information regarding the operating conditions. In this way, used by pilots, AOCs and ATC, flight trajectories that are more advantageous to the operator can be successfully flown.
[0011] The subject matter of the present application recognizes the previously unmet need and provides tools, systems and methods that can calculate an advantageous flight profile that takes into account developing operational conditions, air traffic constraints and aircraft performance in a timely manner that can allow tactical flight plan changes to be incorporated without unduly introducing operational or financial penalties to the operator.
[0012] Current practice focuses on using the CI to balance fuel cost with all other time dependent costs to find the best operating point for the operator (i.e. balance between time of flight and cost of fuel for faster flights). Aircraft today are flown on a selected cost index, which in turn defines the speed and vertical profile of the aircraft. Due to the limited processing power of current flight management systems, algorithms generating the speed and vertical profiles are relatively simple and cannot generate outputs that are sufficiently close to a theoretical optimal output. Accordingly, known methods of operation do not provide the best gains.
[0013] Operationally, in order to operate at the optimal operating point, the flight trajectory and schedule needs to be known. These factors, however, are often tactically altered by air traffic constraints. Currently, air traffic controllers do not plan restrictions sufficiently early to support the efficient planning of optimal flight. As a result, aircraft operators may plan for aircraft to fly optimally, only for their plans to be changed by tactical instructions by ATC. There is value therefore, in enabling the planning of ATC restrictions in advance so that, in conjunction with the generation of flight trajectories closer to the theoretical optimum, aircraft can be flown in a more efficient manner.
[0014] Also, consistently rising fuel prices have driven airlines into rethinking their business models, adopting approaches that reduce costs, as well as the impact of their operations on the environment. An approach that offers great potential and has attracted the attention of the aviation industry is the management of trajectories for “green” operations.
[0015] The Flight Trajectory Optimization and Visualization Tool which is the subject of the present application is capable of optimising the trajectories of aircraft, thus allowing the tool to be used by various stakeholders, such as pilots in the cockpit and air traffic controllers and staff in airline operating centres on the ground.
[0016] In order to be used as a ground based ATC tool or airline operations centre (AOC) tool, data pertaining to the aircraft and operating conditions (e.g., weight and cost index) may need to be obtained from the AOC and/or the flight crew. Output profiles generated by the tool when used on the ground can then be communicated to the aircraft in a plurality of ways, such as under existent procedures via voice radio or via the use of digital data links. This may be done either in direct communication with the aircraft or via the AOCs.
[0017] The present invention is intended to mitigate at least some of the difficulties associated with current systems. For the purposes of this invention, the flight trajectories of interest are expected to primarily be the climb and descent although other phases of flight, including cruise, are also included.
[0018] Typical inputs to the present invention may include aircraft weight, time of flight or cost index, weather conditions (including wind), ATC constraints and the intended flight plan. The output of the tool is an optimized trajectory profile that identifies salient points along the trajectory profile, such as top of climb and top of descent points and other operational factors, such as the speed schedule and flight constraints.
[0019] The merits of a ground-based optimization tool become evident when considering the operational environment, as well as certification aspects of technology. For example, currently ATC instructs a flight crew with constraints that are based on the need for aircraft separation and naturally upset the CI calculations and business model of the aircraft operator. More seriously, often ATC currently do not have objective means to introduce constraints that are sensitive to the airline business model and, as a result, often issue constraints that impact the operator negatively. Consequently, an ATC tool that is sensitive to such issues would be highly beneficial. This approach, whilst conceptually enabling ATC, also avoids the complications of aircraft certification besides that of equipage. Furthermore, the present invention is designed to integrate seamlessly with current operational practices, which is advantageous.
[0020] The Flight Trajectory Optimization and Visualization Tool can also be provided as an auxiliary tool on a tablet (or similar device) for the flight crew to use during flight. Pilots already carry and use tables for planning purposes today and the Flight Trajectory Optimization and Visualization Tool will be in line with current practices so as to be usable on such devices.
[0021] In an example embodiment, the Flight Trajectory Optimization and Visualization Tool provides a method and system that identifies, in a timely manner, an optimized flight trajectory and profile to allow flight crews to fly more efficient trajectories, thus overcoming at least some of the limitations of prior art.
[0022] In an example embodiment, there is provided a method that determines, during pre-flight and/or flight, an optimized trajectory and associated operating point of an aircraft, according to aircraft performance indicia, operating conditions and operational constraints.
[0023] By taking into account aircraft performance and up-to-date operating conditions and operational constraints simultaneously, the method is capable of determining more advantageous flight trajectories and profiles according to criteria set by the operator, such as fuel burn, time of flight, noise, emissions or cost index.
[0024] The operating conditions considered may include, but are not limited to, atmospheric conditions such as temperature, pressure, wind and other weather conditions, as well as aircraft weight.
[0025] The operational constraints considered may include, but are not limited to, air traffic constraints, any routing constraint, flight time and ability to fly particular flight profiles. Advantageously, the flight plan or path followed by the aircraft may be stored in a database and/or memory that may contain waypoint, speed, heading and altitude data.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] An exemplary embodiment of the invention will now be described with reference to the accompanying drawings, in which:
[0027] FIG. 1 illustrates an example embodiment of a system that includes the Flight Trajectory Optimization and Visualization Tool;
[0028] FIG. 2 shows an example embodiment of the computing device in which the tool in FIG. 1 may be installed and executed;
[0029] FIG. 3 shows an example graphic generated by the graphical user interface of the tool in FIG. 1 ;
[0030] FIG. 4 shows an example graphic generated by the graphical user interface of the tool in FIG. 1 , showing a fuel-optimized flight plan created in accordance with the functions of the tool of FIG. 1 ;
[0031] FIG. 5 illustrates an example graphic generated by the graphical user interface of the tool in FIG. 1 , showing the profiles pertaining to the optimised trajectory of a flight;
[0032] FIG. 6 is a flowchart of an example process of optimizing trajectories via the tool of FIG. 1 ; and
[0033] FIG. 7 presents a flowchart of an example optimization process of step of FIG. 6 using a pseudo-spectral technique to optimise flight trajectories.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0034] Various example embodiments will now be described more fully with reference to the accompanying drawings in which some example embodiments are shown.
[0035] Detailed illustrative embodiments are disclosed herein. However, specific structural and functional details disclosed herein are merely representative for purposes of describing example embodiments. This invention may, however, be embodied in many alternate forms and should not be construed as limited to only the embodiments set forth herein.
[0036] Accordingly, while example embodiments are capable of various modifications and alternative forms, the embodiments are shown by way of example in the drawings and will be described herein in detail. It should be understood, however, that there is no intent to limit example embodiments to the particular forms disclosed. On the contrary, example embodiments are to cover all modifications, equivalents, and alternatives falling within the scope of this disclosure. Like numbers refer to like elements throughout the description of the figures.
[0037] Although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and similarly, a second element could be termed a first element, without departing from the scope of this disclosure. As used herein, the term “and/or,” includes any and all combinations of one or more of the associated listed items.
[0038] When an element is referred to as being “connected,” or “coupled,” to another element, it can be directly connected or coupled to the other element or intervening elements may be present. By contrast, when an element is referred to as being “directly connected,” or “directly coupled,” to another element, there are no intervening elements present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between,” versus “directly between,” “adjacent,” versus “directly adjacent,” etc.).
[0039] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms “a,” “an,” and “the,” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes,” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
[0040] It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures unless otherwise indicated. For example, two figures shown in succession may in fact be executed substantially concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
[0041] Specific details are provided in the following description to provide a thorough understanding of example embodiments. However, it will be understood by one of ordinary skill in the art that example embodiments may be practiced without these specific details. For example, systems may be shown in block diagrams so as not to obscure the example embodiments in unnecessary detail. In other instances, well-known processes, structures and techniques may be shown without unnecessary detail in order to avoid obscuring example embodiments.
[0042] In the following description, illustrative embodiments will be described with reference to acts and symbolic representations of operations (e.g., in the form of flow charts, flow diagrams, data flow diagrams, structure diagrams, block diagrams, etc.) that may be implemented as circuits, program modules or functional processes include routines, programs, objects, components, data structures, etc., that perform particular tasks or implement particular abstract data types and may be implemented using existing hardware. The operations be implemented using existing hardware in existing electronic systems (e.g., display drivers, System-on-Chip (SoC) devices, SoC systems, electronic devices, such as personal digital assistants (PDAs), smartphones, tablet personal computers (PCs), laptop computers, etc.). Such existing hardware may include one or more Central Processing Units (CPUs), digital signal processors (DSPs), application-specific-integrated-circuits (ASICs), SoCs, field programmable gate arrays (FPGAs), computers, or the like, configured as special purpose machines to perform the functions described herein as well as any other well-known functions of these elements. In at least some cases, CPUs, SoCs, DSPs, ASICs and FPGAs may generally be referred to as processing circuits, processors and/or microprocessors.
[0043] Although a flow chart may describe the operations as a sequential process, many of the operations may be performed in parallel, concurrently or simultaneously. In addition, the order of the operations may be re-arranged. A process may be terminated when its operations are completed, but may also have additional steps not included in the figure. A process may correspond to a method, function, procedure, subroutine, subprogram, etc. When a process corresponds to a function, its termination may correspond to a return of the function to the calling function or the main function.
[0044] As disclosed herein, the term “memory,” “memory unit,” “storage medium,” “computer readable storage medium,” and the like, may represent one or more devices for storing data, including read only memory (ROM), random access memory (RAM), magnetic RAM, core memory, magnetic disk storage mediums, optical storage mediums, flash memory devices and/or other tangible machine readable mediums for storing information. The term “computer-readable medium” may include, but is not limited to, portable or fixed storage devices, optical storage devices, and various other mediums capable of storing, containing or carrying instruction(s) and/or data.
[0045] Unless specifically stated otherwise, or as is apparent from the discussion, terms such as “processing” or “computing” or “calculating” or “determining” or “displaying” or the like, refer to the action and processes of a computer system, or similar electronic computing device, that manipulates and transforms data represented as physical, electronic quantities within the computer system's registers and memories into other data similarly represented as physical quantities within the computer system memories or registers or other such information storage, transmission or display devices.
[0046] Furthermore, example embodiments may be implemented by hardware, software, firmware, middleware, microcode, hardware description languages, or any combination thereof. When implemented in software, firmware, middleware or microcode, the program code or code segments to perform the necessary tasks may be stored in a machine or computer readable medium such as a computer readable storage medium. When implemented in software, a processor or processors will perform the necessary tasks.
[0047] A code segment may represent a procedure, function, subprogram, program, routine, subroutine, module, software package, class, or any combination of instructions, data structures or program statements. A code segment may be coupled to another code segment or a hardware circuit by passing and/or receiving information, data, arguments, parameters or memory contents. Information, arguments, parameters, data, etc. may be passed, forwarded, or transmitted via any suitable means including memory sharing, message passing, token passing, network transmission, etc.
[0048] In an example present embodiment, the Flight Trajectory Optimization and Visualization Tool (hereinafter “the tool”) is described for use on the ground by Air Traffic Control personnel. It is understood, however, that variations of the tool can be implemented for use on the ground by airlines (such as AOCs), as well as airborne on the flight deck. For example, the tool can be provided on a portable computing device, such as a tablet, mobile telephone, laptop computer (or other similar device) for the flight crew to use during flight.
[0049] Certain parameters and constraints associated with the optimization process, such as ATC constraints or aircraft operating weight may need to be communicated verbally via voice radio or via datalink between the AOC, ATC and the flight deck. Furthermore, in the case of use of the tool by the AOC or on the flight deck, the flight crew will need to request new clearances from ATC to execute an optimal trajectory that may deviate from that for which the aircraft is cleared to fly. It is understood that this exchange of information, whether verbal or in digital format, is carried out via one or a plurality of datalinks as shown in FIG. 1 . It is also contemplated herein that the subject matter of the present application may be integrated in a FMS and linked with the automatic guidance system of the aircraft. When this is not the case, pilots will need to program the flight guidance system to follow the trajectory profile they identify (and not follow the FMS).
[0050] As shown in FIG. 1 , a present embodiment of the flight trajectory optimization and visualization tool 1 (hereinafter “the tool”) organised as a ground-based tool used for optimising aircraft trajectories comprises part of a system 100 that includes a computing device 90 , the user 200 , the ownship (the aircraft for which the trajectory is being optimised) and other aircraft 210 , as well as other agencies 220 providing data, such as meteorological offices. It is understood that other agencies 220 is also considered to include ATC and AOCs, which may provide traffic and other data to the computing device 90 . In an example embodiment, the computing device 90 on which the tool 1 is installed is a personal computer (PC) that may further form part of a ground based ATC or AOC tool.
[0051] It is understood that in another embodiment, the tool 1 may be installed as an airborne tool, either integrated in aircraft systems or used using portable computational devices such as laptops and tablets. It is also understood that this and other embodiments may comprise a subset of the embodiment of FIG. 1 . For example, when the tool is used to optimise only one aircraft's (the ownship's) flight trajectory, other aircraft 210 may not form part of the system. Likewise, the system may be ‘stand-alone’ and not linked to other agencies 220 . By way of a non-limiting example, the following figures and embodiments describe a ground based tool, as it essentially comprises a super-set of the airborne embodiment.
[0052] FIG. 2 is a diagram illustrating an example embodiment of the computing device 90 in which the tool 1 may be installed and executed. It is understood that the computing device 90 may physically comprise of a plurality of physical computational devices such as PCs or high performance computers. In another embodiment, the computing device 90 is a portable computing device such as a tablet, laptop computer, etc. Referring to FIG. 2 , in a present embodiment, the computing device 90 includes a data bus 11 ; an data input unit 15 that may include one or a plurality of devices such as, but not limited to, a keyboard, mouse, tracker ball, touch screen and/or other input devices such as wired and/or wireless data network devices and associated sub-systems that connect the computing device 90 to other systems external to the computing device 90 such as other agencies 220 ; a processor 13 ; a memory 17 that may comprise volatile memory (RAM), non-volatile memory (ROM) and a storage device; a display 19 ; and a data output unit 18 that can output data in digital format to other systems and sub-systems external to the computing device 90 , including other agencies 220 . It is understood that the data output unit 18 may include one or a plurality of devices such as, but not limited to, wired and wireless I/O devices and sub-systems. The data input unit 15 , processor 13 , memory 17 , display 19 , and data output unit 18 may send a receive data to one another via the data bus 11 .
[0053] The data input device 15 is a device that includes the necessary hardware and/or software for receiving data including, for example, user input data and traffic data, via one or more wired and/or wireless connections to one or more internal and/or external data sources. The processor 13 may be, for example, a microprocessor capable of executing instructions included in computer readable code. The term ‘processor’, as used herein, may refer to, for example, a hardware-implemented data processing device having circuitry that is physically structured to execute desired operations including, for example, operations represented as code and/or instructions included in a program. Examples of the above-referenced hardware-implemented data processing device include, but are not limited to, a microprocessor, a central processing unit (CPU), a processor core, a multi-core processor; a multiprocessor, an application-specific integrated circuit (ASIC), and a field programmable gate array (FPGA).
[0054] The memory 17 may be any device capable of storing data including magnetic storage, flash storage, or similar, including for example, RAM, ROM, Flash memory, hard disk, or other known storage device. The display 19 may be any device capable of displaying data including, for example, a computer monitor, a tablet or personal device display, or similar. The display 19 may also include a touch screen capable of receiving user input commands, which touch screen may form part of the data input device 15 .
[0055] It is understood that the data input device 15 and data output unit 18 include all necessary devices and sub-systems necessary for the disclosed functions of data input and output. For example, in the case of wireless networks, the data input device 15 and data output unit 18 include all of the necessary wireless communication subsystems including wireless transmitters and receivers, whilst for wired systems the data input device 15 and data output unit 18 include all of the infrastructure for wired communications.
[0056] The tool 1 in the system 100 may further comprise a plurality of subsystems including, but not limited to, an optimizer module 8 , an output subsystem 6 , a graphical user interface (GUI) 10 that includes various modules and units, a database subsystem 12 , a models subsystem 14 , a weather subsystem 20 , an ATC subsystem 22 , a datalink subsystem 24 and a traffic subsystem 26 .
[0057] The database subsystem 12 may include a plurality of databases in which data pertaining, but not limited to, the aircraft and its flight path, are stored. In a present embodiment, one of the databases includes detailed aerodrome information such as, but not limited to, airspace characteristics, name, runway properties, runway heading, altitude, a list of waypoints surrounding the aerodrome, and departure and arrival procedures. Another database contains aircraft-related data, which includes information such as the manufacture name, aircraft type, model and registration or tail number. Yet another database contains the flight plan, including departure, en route and arrival information and a fourth database contains a list of specific aircraft performance and engine models (referred to as the APEM database) that reside in the models subsystem 14 . These and other databases as will be further described are in communication with the GUI 10 . It is understood that other data can be stored in the database subsystem 12 and that data can be organized differently or in different databases in the database subsystem 12 .
[0058] In an example embodiment, an AGTD database may be provided to link an aircraft with its respective aircraft and engine models via the APEM database. The AGTD database may be designed, for example, in SQL to provide the link. The AGTD database may contain fleet information for different airlines that collaborate with ATC in using such an optimization tool to generate optimized trajectories. The AGTD database is organized with a table for each such airline. Each table includes, for example, aircraft information specifying the aircraft manufacturer, general type (referred to as the aircraft model), series for each general type, and the aircraft registration which is unique to each aircraft and is used as the primary key. Each aircraft specified within the AGTD database relates to a particular entry in the APEM database and thus a link is created to the particular aircraft performance and engine models within the models subsystem 14 that mathematically describes the chosen aircraft. The aircraft performance and engine model parameters, which may be general for the aircraft type or subtype or specific for the particular tail number, are then passed to the optimizer 8 of the tool 1 so that each optimization process is specific to an aircraft or aircraft type.
[0059] In an example embodiment, an airspace database in the database subsystem 12 contains data that defines the airspace surrounding the aerodrome, in which trajectories are to be optimized according to the criteria of interest, such as fuel burn or emissions. The database may include, for example, a table listing a sector name, lower and upper airspace limits and the airspace area shape, which, in turn, defines the edges of the airspace area. The corners of the area are defined in latitude and longitude, with the last in the series being connected to the first to close the polygon. The position of the standard entry and exit points of the airspace may also specified, these typically marking the start and end of airways, Standard Terminal Arrival Routes (STARs) and Standard Instrument Departures (SIDs).
[0060] In an example embodiment, an aerodrome configuration database may be provided in the database subsystem 12 . This database contains information that defines a particular aerodrome, the airspace surrounding the aerodrome, and the arrival and departure routes of the aerodrome. The information includes, for example, a table containing the name of the airport together with the IATA code and the ICAO code, the geographic aerodrome reference point (ARP) specified in latitude and longitude in decimal degrees, the aerodrome elevation above mean sea level (AMSL), the runway designation which identifies the runways at the aerodrome and their orientation, the latitude and longitude co-ordinates at the runway thresholds, the elevation above mean sea level (AMSL) at the threshold of each runway and the country name and identifier as allocated by the International Telecommunications Union (ITU). The SIDs and STARS are also defined in detail within the aerodrome database. Data associated with these includes the route name, the type (whether arrival, departure or approach) and whether it should be followed according to specific procedures such as RNP-AR. The route is defined by a series of waypoints, each specified in latitude and longitude and may include speed and altitude constraints and the path termination at each waypoint as defined by the ARINC-424 database stored in the ATC subsystem.
[0061] The models subsystem 14 includes, but is not limited to, the afore-mentioned aircraft performance and engine models and an atmospheric model that models the International Standard Atmosphere (ISA) and allowing for temperature and other parameter deviations that are, in a present embodiment, either input by the user 200 or obtained from other agencies 220 via the input data unit 15 .
[0062] The weather subsystem 20 stores and handles weather data including, for example, actual or forecast wind and temperature data. This data may, for example, be input by the user 200 or obtained from other agencies 220 via the input data unit 15 . Typically such data would span from ground level up to 40,000 feet for the region of interest around the flight trajectory being optimised and allows the consideration of variations in parameters that affect aircraft and engine performance. Because the manual inputting of data is generally cumbersome, data is preferably retrieved via weather forecasts or reports in electronic format from other agencies 220 such as meteorological stations or other aircraft 210 that can relay weather information in the system 100 via the input data unit 15 .
[0063] The ATC subsystem 22 contains and handles data that includes, but is not limited to, ATC constraint information pertaining to the trajectory or trajectories being optimised. Such constraints may be, but are not limited to speed, altitude and time-of-arrival constraints.
[0064] The datalink subsystem 24 is a subsystem by which the tool 1 sends and receives electronic transmissions via the data input unit 15 and data output unit 18 . In a present embodiment, the said electronic transmissions include those associated with weather information and flight plans. The datalink subsystem 24 is connected to the weather, ATC and traffic subsystems 20 , 22 and 26 , as well as with the GUI 10 within the tool 1 . The datalink can be wired (in the case of land-based communication) or wireless. In the present embodiment for ATC use, the datalink subsystem 24 within the tool 1 resides in a PC 90 that is electronically equipped to transmit and receive data over a wired ETHERNET communication link that further connects to standard industrial hardware providing wireless communication with other aircraft 210 .
[0065] The traffic subsystem 26 stores and handles information regarding traffic in the vicinity of or within the aerodrome or area of interest obtained from other aircraft 210 or other agencies 220 via the data input unit 15 and datalink subsystem 24 . The provided information may include, but is not limited to, aircraft call sign, position, speed, altitude and heading, which may be displayed on the graphical user interface (GUI) 10 and used to select particular aircraft for which the trajectory is to be optimised or to formulate constraints in the optimization process.
[0066] In an example embodiment, the GUI 10 is designed to support manual as well as automatic entry of all the data required for optimization of flight trajectory. The GUI 10 includes control of and interaction with the optimization process carried out by the optimizer module 8 and provides for the visualisation of trajectories and other features relevant to the user such as the position of other traffic and geographical features. In an example embodiment, flight path information can be obtained directly from the database subsystem 12 and other data, such as weather (wind and temperature) information can be obtained automatically through communication with the relevant subsystems 12 , 14 , 20 , 22 and 26 .
[0067] The GUI 10 includes a selection module 3 , a data input module 4 and a visualization module 5 . The selection module 3 enables a user 200 of the tool 1 to select relevant parameters such as the model of a specific aircraft and a flight plan for optimization from the database subsystem 12 from the database subsystem 12 . The GUI 10 also allows the user, through the data input module 4 , to input or vary any necessary data or parameter that may be specific to a particular trajectory segment of flight plan to be optimised and is that not stored in the database subsystems such as the database subsystem 12 , the weather subsystem 20 , traffic subsystem 26 and ATC subsystem 22 . In addition, the data input module 4 also allows data entered manually into the tool 1 and stored in the said subsystems 12 , 20 , 22 and 26 .
[0068] The visualization module 5 of the GUI 10 provides for the visualisation of trajectories and other features relevant to the user such as the position of other traffic and geographical features. Accordingly, the visualization module is capable of displaying the trajectory 54 of the flight plan selected from the database subsystem 12 overlayed graphically on a geographic map 59 that is stored within the database subsystem 12 . An example visualisation graphic 58 is shown in FIG. 3 . Typically, a trajectory is defined by a plurality of waypoints 56 stored in the database subsystem 12 . Specific parts of the trajectory to be optimised can be selected by the user through the graphical selection of two (the initial and final) waypoints via the use of an input device such as a mouse, touch screen or tracker ball. The data pertaining to the selected part of the trajectory are then passed from the visualisation module 5 to the selection module 3 , which handles data pertaining to the selected part of the trajectory to be optimised. In a present embodiment, the visualisation module 5 is also capable of displaying traffic data received from the traffic subsystem 26 on the display as represented by visualisation graphic shown in FIG. 3 . The visualisation module 5 is also capable of graphical manipulations that are known, such as panning and zooming which may be achieved by selecting the appropriate icons 50 and 52 via an input device such as a mouse, touch screen or tracker ball, that forms part of the data input unit 15 . It is understood that various forms of display features associated with, but not limited to, panning, zooming and rotation of the graphic or parts thereof form part of the disclosure.
[0069] In an example embodiment, details pertaining to the flight plan may also be displayed in textual format on a side pane 46 of the graphic 58 . Data pertaining to the initial and final operating conditions of the selected section of flight path to be optimised are displayed on a second side pane 48 , what those pertaining to the aircraft are displayed on a third side pane 44 . It is understood that this and other data may be displayed in other configurations and formats. The textual data displayed on the graphic 5 generated by the visualisation module may be altered by the user 200 via an input device such as a keyboard, touch screen, mouse or tracker ball within the data input unit 15 and the newly entered data is then stored within the database subsystem 12 . In a present embodiment, on side pane 46 , data pertaining to the section of the flight plan selected for optimization is displayed in a colour that is different from that used to display data relating to the rest of the flight plan.
[0070] In an example embodiment, parameters in the optimization process, such as aircraft weight and, potentially, cost index, are considered to be included in the flight plan data, which may be updated in real-time by the aircraft 210 to reflect more recent estimates of aircraft actual weight. In one embodiment, the side pane 46 incorporates a flight plan table 46 that lists waypoints 56 in sequential order and allows the deletion and addition of waypoints 56 by the user to alter the plan path of the trajectory to be optimized. Time, speed and altitude constraints can be defined by the user at different waypoints on the flight plan table in side pane 46 and this information is stored in the ATC subsystem 22 . In an example embodiment, constraints can take the form of AT OR ABOVE, AT OR BELOW, or AT a specific threshold or value.
[0071] The optimizer module 8 within the tool 1 optimises the section of the flight plan selected for optimization by the user 200 . The optimizer 8 uses optimization algorithms, such as those using evolutionary techniques and optimal control theory. In a present embodiment, the optimizer module 8 accesses the necessary models within the models subsystem 14 (such as those pertaining to aircraft performance) as well as weather information from the weather subsystem 20 , ATC constraints from the ATC subsystem 22 and traffic information from the traffic subsystem 26 .
[0072] The optimizer module 8 optimises the flight trajectory for one or a plurality of objectives that are entered by the user 200 in the data input module 4 or visualisation module 5 of the GUI 10 . For example, one objective may be the minimisation of fuel burn. Another objective may be the minimisation of flight time. A further objective may be the minimisation of emissions. Yet another objective may be the minimisation of perceived noise generated by the aircraft. For example, a trajectory may be optimized for minimum fuel burn or minimum flight time, or a balance between the two. Alternatively, flight time may be defined as an ATC constraint in the ATC subsystem 22 , in which case the optimizer 8 may generate speed and altitude schedules for minimum fuel burn for the specified flight.
[0073] When the optimization process for the selected section of the flight plan is complete, the optimization module 8 outputs the result to the output unit 6 of the tool 1 . The output unit 6 formats the optimised trajectory in a format that can be used by the user 200 or the aircraft 210 . Example formats of an optimised trajectory, which is useful for pilots and systems on board the aircraft 210 involve speed and altitude schedules, as this allows pilots a simple way to program aircraft systems such as the flight guidance and flight management systems. It is understood that the output unit 6 can re-format the optimised trajectory in different ways as may be appropriate for the particular application. For example, the output unit 6 also formats the data in tabular format for display by the visualisation module 5 in tabular format as shown in FIG. 4 and in graphical formats as shown in FIG. 5 . Example data input to the optimizer 8 includes track miles to be flown in the trajectory segment to be optimized and trajectory segment start and end point altitudes. Such data may be extracted or derived from the flight plan.
[0074] Constraints along the trajectory, such as those pertaining to speed and altitudes at specific points on the trajectory, are retrieved from the relevant databases of the database subsystem 12 . It is understood that different trajectory parameters may be retrieved, that trajectory profiles may be described in different formats and other criteria, such as emissions may be included in the optimization in different embodiments of the present invention. In the present embodiment, these computations are based on pseudospectral techniques.
[0075] In an example embodiment, the optimizer 8 generates a trajectory defining the speed and altitude schedules along the plan path, as well as, where applicable, salient points such as Top of Climb (ToC) or Top of Descent (TOD). These points are transferred to the output unit 18 that handles the data and formats it into forms compatible with other internal subsystems and external systems. For example, the output unit 18 formats data for display of the trajectory on the GUI 10 on the display 19 . This supports the visualization of the optimized trajectory by the user 200 . The output unit 18 may also format the data in a way that is compatible with existent ATC formats or other datalink formats that allow transfer of the data to an aircraft. The output unit 18 further transfers data to other agencies 220 via the datalink subsystem 24 and data output unit 18 .
[0076] The tool 1 can be configured to operate in one or a plurality of operating environments, such as in the cockpit, in an AOC or within ATC. This may result in variations of the described embodiment. For example, in a present embodiment for use by pilots on the flight deck, the computing device 90 is a tablet and therefore the traffic subsystem may not be implemented as it is not used. In such an embodiment, the user 200 is the pilot or pilots who manually enter the data via the touch screen of the tablet, which forms part of the data input unit 15 and reads the speed and altitude schedules of the optimised trajectory generated by the optimizer module 8 and displayed by the visualisation module 5 to then program the flight management system or the autopilot of the aircraft 220 or fly the aircraft 220 manually.
[0077] It is understood that in yet other embodiments the tool 1 within the computing device 90 may connect with the systems of the aircraft 220 via a wired or wireless link implemented in the data input unit 15 and the data output unit 18 . This would allow the automatic transfer of data pertaining to, for example, flight management and air data. Likewise, the computing device 90 may also communicate with other agencies 220 via the data input unit 15 and data output unit 18 which, in such an implementation, may include other aircraft or weather stations for the collection of weather data, ATC for ATC constraints and clearances, and the AOC for information purposes.
[0078] When the tool 1 is configured to operate as a ground-based tool, either within an AOC or ATC, the user 200 may communicate data pertaining to the optimised flight trajectory such as speed and altitude schedules to the pilot or pilots on board the aircraft 210 via voice radio. Alternatively, the computing device 90 may communicate with the systems on board the aircraft 220 via a wireless data link implemented in the data input unit 15 and data output unit 18 and with other agencies (which may include ATC in the case the tool is used by an AOC and vice versa) via a wired or wireless link.
[0079] In an example embodiment the GUI 10 as shown in FIG. 3 , a menu bar 42 with a movable map 40 with zoom and pan functions are controlled by pan buttons 50 and zoom buttons 52 , respectively. Different aircraft (traffic) 59 may be displayed and one or more aircraft may be selected by an input device such as a mouse to display its planned plan path 54 defined by the flight plan. In an example embodiment, placing a cursor or other pointing device on an aircraft symbol 59 will temporarily display information such as call sign, type, etc. on the map 40 adjacent to the said aircraft symbol. The optimizer 8 may also be initiated by the GUI GUI 10 . In an example embodiment, the GUI 10 may include a graphical or virtual button to initiate the optimizer 8 .
[0080] If the tool 1 is being used by an AOC, it may be relevant to transmit the optimized trajectory to ATC (agency 220 ), as well as the associated aircraft 210 to allow pilots to fly the proposed trajectory. When the tool 1 is used by ATC, data may be transmitted to the AOC and relevant aircraft, whilst when the tool 1 is used on the flight deck, data may be transmitted to ATC and the AOC. It is also possible that if the tool 1 is installed on a portable device on the flight deck, the tool 1 would transmit data to appropriate aircraft systems, such as the Flight Management System (FMS). Alternatively, the pilot may input relevant data pertaining to the optimized trajectory manually into the FMS. In the case of the tool 1 being on the ground, data pertaining to the optimized trajectory, such as operating speed and other salient information such as altitudes or the ToC or TOD points may be relayed to the pilots via voice radio and the pilots can then program the FMS accordingly.
[0081] In an example embodiment, the GUI 10 can also display speed and altitude schedules and other information such as expected time of arrival (ETA) for various waypoints and other salient points pertaining to the optimized trajectory. An example display is shown in FIG. 4 . The GUI 10 may also display data pertaining to the optimized trajectory in graphical format such as that shown in FIG. 5 .
[0082] The process of optimising a flight trajectory using the tool 1 and system 100 as presented in a present embodiment is shown in FIG. 6 . According to example embodiments, each of steps illustrated in FIG. 6 may be performed by a combination of inputs by the user 200 and execution of processes by the tool 1 operating in the system 100 , where the memory 17 stores executable instructions corresponding to the relevant steps illustrated in FIG. 6 , and the processor 13 performs the operations corresponding to the steps illustrated in FIG. 6 . According to example embodiments, received data, including weather, traffic, etc., from databases/subsystems may be received through the data input module 4 , and data produced as a result of performing the steps illustrated in FIG. 6 may be output to an external entity via the data output unit 18 and/or displayed on the display unit 19 .
[0083] The steps illustrated in FIG. 6 may be embodied in the form of computer code stored in a tangible non-transitory computer readable medium including, for example, an optical disc, flash drive, HDD, or other known types of such computer readable media. The computer code includes instructions capable of causing a computer to perform operations corresponding to the steps illustrated in FIG. 6 .
[0084] In the first step of the optimization process shown in FIG. 6 (step 80 ), the tool 1 automatically collects the latest updated data pertaining to weather and traffic from other agencies 220 and stores it in the memory 17 . Weather data, obtained from weather agencies, includes, but is not limited to, ambient temperature, pressure, wind speed and direction at different altitudes and geographic positions and is handled by the weather subsystem 20 . Traffic data is obtained from ATC or AOC systems and is handled by the traffic subsystem 26 and includes a list of aircraft from which the user 200 can select the aircraft for which a segment of the trajectory will be optimised; together with associated data pertaining to each aircraft and its flight such as its weight, position, altitude, speed and flight plan. The flight plan of each aircraft is stored in the database subsystem 12 . The selection module 3 of the GUI 10 generates a table of aircraft from which the user 200 can select one on which the trajectory optimization process will be performed. Traffic data is, in a present airborne embodiment of the tool 1 , only related to the ownship and this is obtained from the systems of the aircraft 210 such as the flight management system and air data system. Alternatively, the user 200 may enter the data, or parts thereof, manually using the data input device 15 and the input module 4 of the GUI 10 . The visualisation module 5 is capable of displaying the traffic overlayed on a map in the format as shown in FIG. 3 using symbols 59 to represent traffic.
[0085] Next, in step 82 , the user 200 selects the aircraft of interest from the table generated by the selection module 3 of the GUI 10 . This can be done by either selecting the aircraft of interest from the table generated by the selection module 3 or by graphically selecting (using, for example a mouse 15 ) the relevant aircraft symbol 59 displayed on the map generated by the visualisation module 5 ( FIG. 3 ). In the latter case, the user 200 has the opportunity to pan and zoom on the map using the virtual buttons 50 and 52 to bring the aircraft of interest into view.
[0086] Once the aircraft of interest is selected, the tool 1 seeks the flight plan associated with the selected aircraft (step 84 ) in the database subsystem 12 and loads it into the memory unit 17 (step 88 ). If, for any reason, the flight plan is not found in the database subsystem 12 , the user is prompted by the data input module 4 to manually enter the flight plan details via the GUI 10 (step 86 ). This can be done via the data input module 4 or via the side pane 46 of the graphic 58 generated by the visualisation module 5 ( FIG. 3 ). Flight plan details entered generally include a waypoint name and the time, altitude and speed at/with which the aircraft will overfly it. The tool 1 may then automatically generate the distance to the next waypoint and ground track resulting from the leg joining two successive waypoints and display these data on the side pane 46 . Once the flight plan is entered manually it is stored in the database subsystem 12 . Furthermore, once a flight plan is identified, it is displayed on the graphic 58 generated by the visualisation module 5 as shown in FIG. 3 .
[0087] Next, the user 200 needs to select the segment of the flight that is to be optimised (step 90 ) via the graphic 58 generated by the visualisation module 5 . This can be achieved using a mouse to select respective initial and final waypoints that are either displayed on the map (such as waypoint 56 in FIG. 3 ) or else as listed in the side pane 46 . In a present embodiment, by selecting (by, for example clicking with a mouse or touching the touch screen on) the region of ‘Initial WPT’ and ‘Final WPT’ in side pane 48 will cause the visualisation module 5 to display drop-down menus to allow the user 200 to textually enter the initial and final waypoints and associated operating conditions (such as speed, altitude and time) via a keyboard.
[0088] Once the segment of the flight that is to be optimised is identified, the user 200 can then also manually introduce constraints at each waypoint in the flight plan in pane 46 (step 92 ). This is of relevance because such constraints will condition the solutions generated by the optimizer module 8 . The tool 1 may also automatically introduce additional constraints held within the AC subsystem 22 .
[0089] The tool 1 then loads weather information (such as wind speed, direction, temperature and pressure along the flight path at various relevant altitudes) stored in the weather subsystem 20 , whilst the user 200 also has the opportunity to enter such information manually via the data input module 4 .
[0090] Next, the tool 1 selects the correct models relevant to the selected aircraft from a selection of models held in the models subsystem 14 . It is recalled that the models subsystem 14 holds models for different aircraft types and the tool 1 selects the models (such as engine and aircraft performance models) relating to the specific aircraft for which the trajectory is to be optimised by linking the aircraft type to the relevant models via relational databases stored in the database subsystem 12 . The selected models are retrieved from the models subsystem 12 and loaded into the memory unit 17 (step 96 ). At the end of step 96 , the optimization setup is complete with all the necessary models selected and relevant data available, and is ready for execution of the optimization process.
[0091] The tool 1 then waits for the user 200 to start the optimization process. This is achieved through the GUI 10 via an input device in the data input unit 15 . In a present embodiment, the GUI 10 generates a pop-up window asking the user to click on (or touch, with a touch screen) a virtual button to initiate the optimization process once step 96 is complete.
[0092] The tool 1 then performs the optimization process 98 via the optimiser module 8 . At the end of this process, the optimiser module 8 will have generated an optimised trajectory according to the selected optimization criterion or combination of criteria, thereby allowing the aircraft 220 to be operated with improved fuel efficiencies and economies, for example.
[0093] The data pertaining to the optimised trajectory is stored in the memory unit 17 . In a present embodiment, the data pertaining to the optimised trajectory includes speed and altitude schedules that also define salient points in a flight path such as the position of the bottom and top of climbs and descents.
[0094] The tool 1 then displays data pertaining to the optimised trajectories via the visualisation module 5 of the GUI 10 . In a present embodiment, the data is listed in tabular format in side panes 46 and 48 of the graphic 58 shown in FIG. 4 and is also displayed graphically according to FIG. 5 . It is understood that these are example embodiments and that variations in the method of displaying the information can be made within the context of the current invention. For example, for a present embodiment for use by pilots on the flight deck, the data for an optimised descent includes distance, in track miles, the top of descent point from the nearest waypoint on the flight plan and this may also be displayed and highlighted in the side pane 46 .
[0095] The user 200 can then use the displayed information to either, in the case of a ground-based embodiment, relay the information to the pilot of the aircraft 210 via, for example but not limited to, wireless (radio) voice communication, or, in the case of an airborne embodiment where the user 200 is the pilot, or fly the aircraft according to the optimised trajectory. This can be done in a number of ways such as manually programming the flight management system or the autopilot of the aircraft 220 or manually flying the aircraft 220 .
[0096] Optionally, the tool 1 also transfers data pertaining to the optimised trajectory to other parts of the system 100 that are external to the computing device 90 in step 102 . In a present embodiment, the tool 1 , in step 102 , transfers the data to other agencies 220 . It is understood that the tool 1 may likewise transfer data to systems such as the autopilot or flight management system on board the aircraft 210 , allowing the said aircraft to automatically fly the optimised trajectory and thus affording improved fuel efficiencies and economies.
[0097] The process ends at step 104 .
[0098] The optimization process executed in step 98 can involve one or a combination of a plurality of optimization techniques such as those based on evolutionary (eg. genetic algorithms) and optimal control techniques. In a present embodiment, the optimization process uses pseudo-spectral techniques, which form a sub-set of optimal control techniques. FIG. 7 presents a flow chart of the steps involved in the process of optimising a flight trajectory using pseudo-spectral techniques in a present embodiment.
[0099] Accordingly, the process first involves the optimiser module 8 generating an initial trajectory of the selected flight path segment obtained from step 90 (step 120 ). Advantageously, the initial trajectory is taken directly to be that of the flight plan resident in the database subsystem 12 which may have been altered by the user 200 via the GUI 10 .
[0100] The optimiser module 8 then fits pseudo-spectral polynomials to the aircraft states (such as altitude and speeds at arbitrary points on the trajectory) and controls in step 125 . Aircraft controls are the inputs that dictate the states of the aircraft and, in a present embodiment, include thrust setting and elevator position. Other controls such as, but not limited to, aileron and spoiler position may be used as controls. Polynomials are fitted using known techniques which, in a present embodiment uses the least squares mathematical method.
[0101] Next, in step 130 , the aircraft and atmospheric models obtained from the models subsystem 14 in step 96 , together with data such as that pertaining to the weather and operational constraints obtained in steps 94 and 92 respectively, are used to check whether the polynomials representing the aircraft controls generated in step 125 result in a trajectory with the aircraft states defined by the polynomials representing the aircraft states, also generated in step 125 . This step is carried out to ensure that the polynomials are coherent.
[0102] If the polynomials are found to be coherent (step 132 ), then the process checks, in step 135 , whether the trajectory defined by the polynomials of the aircraft states falls within the path constraints obtained from step 92 . If this is the case, the process proceeds to step 140 , in which the cost of the optimization objective or combination of objectives is calculated. In a present embodiment, the optimization objective is the minimisation of fuel burn. In this embodiment, therefore, in step 140 the total amount of fuel that will be burnt in the flight segment being optimised is calculated.
[0103] Once the cost of the objective is computed, the process proceeds to step 145 . In this step, the process determines whether the optimization process is complete or otherwise according to pre-defined stopping criteria. Stopping criteria may include, but are not limited to, a maximum number of iterations or the improvement in objective cost achieved over the previous iteration being below a minimum threshold.
[0104] If the stopping criteria are not met, the process stores the trajectory in the memory unit 17 and generates a new trajectory with a smaller cost function in step 155 . The new trajectory is generated using known non-linear programming (NLP) solvers and this trajectory is then used in a repeat process that starts again at step 125 , thus creating an iterative loop that is typical and known in numerical optimization processes.
[0105] If the stopping criteria are met in step 145 , the process ends and the final trajectory calculated is a trajectory that is optimised, according to the expected operating conditions (such as wind, temperature, operating weight, and ATC constraints) to minimise the cost the selected optimization criterion or combination of criteria. This trajectory is the output of the optimizer module 8 in step 98 of the process described in FIG. 6 .
[0106] While the present invention has been described and illustrated herein with reference to the preferred embodiments thereof, it will be apparent to those skilled in the art that various modifications and variations can be made therein without departing from the spirit and scope of the invention. Thus, it is intended that the present invention covers the modifications and variations of this invention that come within the scope of the appended claims and their equivalents. | A method and system and tools for optimizing an aircraft flight trajectory that determine an advantageous flight profile that takes into account developing operational conditions, air traffic constraints and aircraft performance in a timely manner that can allow tactical flight plan changes to be incorporated without unduly introducing operational or financial penalties to the operator. | 6 |
FIELD OF THE INVENTION
The invention relates to methods for recycling waste corrugated paperboard. In particular, the invention relates to a method of producing bleachable grade pulps using a mixture of recycled cellulosic materials and wood chips.
BACKGROUND OF THE INVENTION
Previous efforts to recycle cellulosic materials, such as waste corrugated materials, boxcuts (i.e., waste similar to cereal boxes or soda cases/cartons), old newspapers, have focused on various methods to treat the cellulosic material before it is reused by itself or mixed with virgin pulp. For example, U.S. Pat. No. 3,440,134 to Murphy discloses a method for producing an acceptable grade of paper utilizing waste corrugated cardboard and corrugated paper. The method of Murphy comprises the steps of comminuting waste corrugated material, forming a water slurry with said waste, adjusting the solids content of the waste in slurry form to approximately 20%, digesting the comminuted waste slurry with caustic soda in an amount consisting of 10% by weight of the waste, heating the slurry with direct steam to approximately 160° C. for about 3 hours, pulping the digested slurry at a temperature of approximately 35° C. for 3 to 5 minutes, increasing the solids content of the resulting pulp to approximately 30%, and bleaching the pulp as required to achieve a desired brightness.
U.S. Pat. No. 5,147,503 to Nguyen discloses a process and an apparatus for recycling waste cellulosic material including corrugated paperboard to produce a cellulosic fiber pulp. The process involves the steps of cooking the waste cellulosic material, for example, corrugated paperboard, in an aqueous alkaline cooking liquor to produce a brown stock pulp having a kappa number lower than that of the waste material. The recycled pulp can be employed as the sole pulp component of brown paper products, or can be bleached to provide a pulp for white products. The brown stock can be mixed with virgin pulp.
As disclosed in the Nguyen patent, paperboard is typically produced from virgin pulp. The production of virgin pulp involves reacting or cooking wood chips with an alkaline cooking liquor at an elevated temperature. Lignin is a component of the wood chips which is dissolved by the cooking liquor in the manufacture of cellulose pulp. The character of the pulp produced is dependent on the extent of lignin removal from the wood chips, and hence on the residual lignin content of the final pulp. The kappa number represents a measure of residual lignin content. Higher kappa numbers indicate higher residual lignin levels. The kappa number of a brown stock pulp obtained from cooking softwood in a kraft liquor is typically 50 to 100, and such a pulp is used for making linerboard of corrugated paperboard. The kappa number of a brown stock pulp obtained from cooking hardwood in a kraft liquor is typically 130 to 160, and such a pulp is used for making the corrugated medium of the corrugated paperboard. The kappa number of a hardwood brown stock pulp would need to be reduced to about 10 to 15, and that of a softwood brown stock pulp to about 25 to 35 to provide a pulp suitable for bleaching to produce white paper products. Corrugated paperboard waste comprising linerboard and corrugating medium has a kappa number of 80 to 120.
U.S. Pat. No. 4,191,610 to Prior discloses the manufacture of corrugated boxes from a corrugated medium consisting of virgin semichemical pulp, corrugated clippings, old corrugated boxes or mixed waste material using waste liquor.
U.S. Pat. No. 3,925,150 to Marsh discloses a method of recycling corrugated paperboard of the type comprising a fluted layer sandwiched between layers of linerboard. The fluted layer is usually made from relatively low grade and short-fibered pulp, such as neutral sulfite semichemical pulp and short-fibered kraft pulp. The liners are commonly made of a good grade of kraft pulp. When corrugated board is pulped for use as waste paper stock, the high-grade kraft constituents of the liners and the relatively lower-grade fiber constituents of the corrugating medium are thoroughly mixed, and the resulting furnish is no longer suitable as liner stock. The Marsh patent discloses a method for separating used corrugated board into two fractions, one being kraft fiber suitable for use as virgin kraft pulp and the other fraction containing the majority of the semichemical pulp and other short-fibered constituents of the corrugated medium.
Canadian Patent No. 1,110,411 discloses a method for recycling waste consisting of paperboard which has been previously impregnated with waxes or resins in a previous converting process, such as wet strength packaging or furniture component manufacture. To avoid the expense of using original kraft cooking liquor (white liquor) to digest the waste paperboard, Canadian Patent No. 1,110,411 proposes to use the effluent by-product of a prior pulping process, i.e., the weak black liquor from the kraft (sulfate) process for making pulp by cooking wood chips under heat and pressure in a solution of sodium hydroxide and sodium sulfide.
None of the aforementioned prior art discloses or suggests to co-pulp waste cellulosic material with wood chips
SUMMARY OF THE INVENTION
The present invention is a method for recycling cellulosic materials, such as waste corrugated materials, boxcuts and newspapers. In accordance with this method, the waste cellulosic material is used as an alternative fiber source during chemical pulping to replace a fraction of the wood chips. Reusing waste cellulosic materials such as corrugated cardboard and corrugated paper has the benefit of recycling this material and using less wood products in the production of acceptable grades of paper. Utilizing waste cellulosic material also helps minimize the impact of escalating prices and limited availability of wood chips.
In accordance with the method of the invention, the waste cellulosic material is shredded and then fed to the digester along with wood chips. The waste cellulosic material need not be repulped or slurried prior to digestion. The wood chips may be any species of hardwood or softwood. Alternatively, the waste cellulosic material can be co-pulped with non-wood fibrous material, e.g., bagasse. When corrugated material is used as the cellulosic material, normal chemical pulping charges, temperatures and cooking times applied in the case of 100% wood chip pulping can be used for co-pulping the corrugated material and wood chips. After the cooking operation, the pulp is processed as usual for chemical pulping, including the steps of blowing the digester, washing and thickening the brown stock, and bleaching the brown stock under the normal conditions used for the wood or non-wood component co-pulped with the waste cellulosic material. Further screening or cleaning steps may be required to remove debris from waste cellulosic material.
Co-pulping of wood chips and waste cellulosic material provides recycled fiber content in consumer products and enables the cost-effective use of scrap waste cellulosic mate-rial in bleachable grade pulps. Unexpectedly, co-pulping of waste cellulosic material with wood chips gave a higher pulp yield than that obtained using wood chips alone.
Co-pulping in accordance with the method of the invention provides the capability to vary pulp properties by varying the amount of waste cellulosic material used. Co-pulping of waste cellulosic material with wood chips can be accomplished using existing batch or continuous wood chip digesters using pulping conditions established for 100% wood chip pulping. This allows flexibility in the amount of waste cellulosic material combined with the wood chips and provides the critical process robustness essential for routine commercial use. Finally, the use of waste cellulosic material may provide a lower raw material cost than the cost of the wood chips which the waste cellulosic material replaces.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram showing the essential components of a conventional kraft pulp manufacturing system.
FIG. 2 is a graph of total screened yield (%) for various corrugated material contents (%) used in laboratory co-pulping of corrugated material clippings and southern hardwood.
FIG. 3 is a graph of total screened yield (%) for various corrugated material contents (%) used in laboratory co-pulping of corrugated material clippings and southern hardwood with various additives or pretreatment: (♦) prewetting the corrugated material with water; () prewetting the corrugated material with black liquor; (x) prewetting the corrugated material with black liquor and using anthraquinone in the cook; (□) prewetting the corrugated material and the southern hardwood with water and using anthraquinone in the cook.
FIG. 4 is a graph showing tear strength versus tensile strength for handsheets made from a furnish containing various amounts of corrugated clippings (CC) and softwood chips.
FIG. 5 is a graph showing tear strength versus tensile strength for handsheets made from a furnish containing various amounts of corrugated clippings (CC) and hardwood chips.
FIG. 6 is a graph showing tear strength versus tensile strength for handsheets made from a furnish containing various amounts of boxcuts (BC) and softwood chips.
FIG. 7 is a graph showing tear strength versus tensile strength for handsheets made from a furnish containing various amounts of newsprint (NP) and hardwood chips.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIG. 1, the present invention is practiced using a conventional kraft pulp manufacturing system comprising a kraft pulp digester 2 into which wood chips are introduced via line 22, shredded waste cellulosic material is introduced via line 24 and white cooking liquor is introduced via line 26. The shredded waste cellulosic material may be fed to the digester dry or wet with water or other pulping chemicals (e.g., white liquor, black liquor, green liquor, alkaline sulfite liquor, sodium hydroxide solution, sodium sulfide solution, anthraquinone solution [soluble or dispersion] or any combination of these) . The shredded waste cellulosic material can be wetted either prior to or while being fed to the digester 2, thereby increasing the amount of waste cellulosic material per volume for pulping.
In the case of corrugated waste material, the wetting process will decrease the consistency and flatten the fluting in the corrugated material. However, corrugated material will retain its shredded form and will not become a defibered slurry. Wetting, pre-steaming or steam packing of the digester will allow pulping of more corrugated material per volume than dry corrugated material without these treatments. Shredded corrugated material may be detrashed in a wet or dry state.
The waste cellulosic material content may vary from 1 to 99 wt. %, with the remainder being wood chips. The wood chips may be any species of hardwood or softwood. The waste cellulosic material can also be co-pulped with non-wood fibrous materials, e.g., bagasse. The digester feed material may be fed as is, exposed to pre-steaming before entering the digester or steam packed in the digester.
The digester may be operated in a continuous or batch mode. Inside the kraft pulp digester 2, the wood chips and shredded waste cellulosic material are cooked for a period of time under heat and pressure to separate the fibers to produce kraft pulp. Normal chemical pulping charges, temperatures and cooking times applied in the case of 100% wood chip pulping are used for the co-pulping of waste cellulosic material and wood chips. Modification of these conditions may be necessary with varying amounts and types of waste cellulosic material. In particular, as the weight percent of waste cellulosic material in the digester is increased, one or more of the following parameters can be decreased: cooking temperature, cook duration and amount of active chemical (e.g., sodium hydroxide) in the cooking liquor. At the end of the cook, the contents of the digester including pulp and spent cooking liquor (weak black liquor) are discharged through line 28 into a blow tank 4 for temporary retention.
From the blow tank 4 the pulp and black liquor are discharged as unwashed pulp through line 30 into a brown stock washer 6. The function of the brown stock washer 6 is to wash the spent chemicals and impurities out of the pulp, the resultant solution being called "weak black liquor". In a conventional kraft system there are usually a series of brown stock washers with the pulp going from a first washer (e.g., washer 6 indicated in FIG. 1) to successive washers. The pulp is washed in progressively cleaner water, with the wash water moving countercurrently against the progression of the pulp from washer to washer so that the cleanest pulp is washed with the cleanest water in the last washer and the dirtiest pulp is washed with the dirtiest water in the first washer. After washing, the brown stock may be thickened and bleached under the normal conditions used for the wood or non-wood component being co-pulped with the waste cellulosic material. Further screening or cleaning steps may be required to remove debris from the brown stock.
The weak black liquor from washer 6 passes through a conduit 32 into a weak black liquor storage tank 8. From the storage tank 8, the weak black liquor is transferred by a pump 10 through a line 34 into an evaporator 12, from which it emerges through line 36 as concentrated black liquor ready for burning to produce heat energy and recovered sodium chemicals for re-use as original cooking liquor.
The types of waste cellulosic material suitable to practice this invention include, but are not limited to, clean corrugated clippings, old corrugated containers or wax- or resin-treated corrugated material, as well as other cellulosic scrap paper (i.e. newspaper, wet-strength packaging, etc.). The waste cellulosic material may be in the form of clippings, scraps or pellets. Binders for pelletizing the waste cellulosic material include water, pulping liquor, black liquor (or spent liquor for processes other than kraft), green liquor, sodium hydroxide solution, anthraquinone solution, oxidized or partially oxidized white liquor or any combination of the above. Pelletizing will increase the corrugated material weight per volume. Pellets may have consistencies ranging from 40 to 95%.
The process of co-pulping waste cellulosic material and wood chips may be accomplished using a kraft pulping process or some other chemical pulping process, such as acid sulfite, neutral sulfite, alkaline sulfite, soda, kraft-polysulfide and any modification of these processes using pulping catalysts and additives such as anthraquinone and surfactant type digester aids.
EXPERIMENTAL DATA
Laboratory Co-Pulping of Corrugated Clippings and Southern Hardwood. In the first experiment, the feed to the digester consisted of 50% dry corrugated material (brown boxes) and 50% hardwood chips (ratio by oven dry weight). The dry corrugated material was shredded into 1.5-inch square clippings. The hardwood chips consisted of mixed species Southern hardwood chips screened to have a thickness of 2 to 6 mm. The pulping process was carried out in a laboratory digester. The corrugated material and hardwood chips were mixed in the digester basket. Kraft pulping was carried out at 16% active alkali on wood (as Na 2 O), 28.9% sulfidity, 5:1 liquor-to-digester feed ratio, and a time/temperature profile of 60 minutes from 100° C. to 170° C. and 60 minutes at 170° C. After pulping, the basket was removed from the digester and the material in the basket was cooled and washed with tap water. The respective cooked corrugated material and hardwood chips were then separated, fiberized by mechanical means and processed separately to measure various data for the individual components of the cook. Measurement of data for the combined cook was done after the separated pulps were recombined according to their individual yields.
The pulps were tested for kappa number, screened yield, percentage rejects and viscosity. The black liquor was tested for pH and residual alkali. Table 1 shows data for various ratios of corrugated material (CM), i.e., clippings, and southern hardwood (HW) chips. These results show that co-pulp has a higher yield (combined yield in Table 1) than hardwood chips alone. The efficacy of the practice of this invention is shown in FIG. 2, where the combined screened yield is shown to increase generally proportionally to the increase in the corrugated material content and achieves a maximum yield at about 25% hardwood and 75% corrugated material.
Laboratory Co-Pulping of Corrugated Clippings and Southern Hardwood with Additives or Pretreatments. Table 2 includes the results of further experiments performed in a laboratory digester, including prewetting of the CM with black liquor or water, with and without anthraquinone in the cook. Data for different ratios of corrugated material and hardwood chips with pretreatment or additives are shown in Table 2. FIG. 3 again shows that the combined screened yield increases generally proportional to the increase in the corrugated material content and achieves a maximum yield at about 25% hardwood chips and 75% corrugated material.
Pilot Digester Co-Pulping of Corrugated Clippings and Wood Chips. Further experiments were carried in a pilot digester. Corrugated box clippings were recooked in the digester along with wood chips to make an acceptably bright, clean and strong fiber furnish. Box factory corrugated clippings were mixed with Northern wood chips and cooked in the pilot digester. Nine pilot digester cooks were performed: four using softwood chips and four using hardwood chips. One cook recooked 100% corrugated clippings. Kraft pulping of the corrugated clippings/hardwood chips mixture was carried out at 16% active alkali on wood (as Na 2 O). Kraft pulping of the corrugated clippings/softwood chips mixture was carried out at 20.65% active alkali on wood (except for cook #5). All of these mixtures were cooked at a temperature of 170° C. for 115 minutes. These pilot digester studies showed the following: (1) pulp from digester cooks containing corrugated clippings and hardwood chips was slightly stronger and cleaner than pulp made from 100% hardwood chip digester cooks; and (2) pulp from digester cooks containing corrugated clippings and softwood chips was slightly weaker but of comparable brightness and cleanliness levels as pulp made from 100% softwood chip digester cooks. Tables 3 and 4 list the handsheet strength results for the hardwood and softwood pilot digester cooks, respectively. The L, a and b values indicate the shade and lightness of the sample. They were measured using a Hunter L, a, b meter. The values listed for the entry "Ball Mill" refer to the amount of refining the samples received.
The results of recooking corrugated clippings with softwood chips (listed in Table 3) showed that corrugated clippings required less white liquor to cook than did softwood chips, as evidenced by the lower resultant kappa number with increased percentages of corrugated clippings. The softwood chip yield was 44.5%. The yield from recooked corrugated clippings was 66.5%. Compared to pulp made from 100% softwood chips, pulp made from 90% softwood chips and 10% corrugated clippings had comparable kappa numbers, brightness, L, a, and b values, and dirt counts. Handsheet strength values were slightly lower. FIG. 4 shows that as the percentage of corrugated clippings increases, the tear strength v. tensile strength relationship for the handsheet decreases.
The results of recooking corrugated clippings with hardwood chips (listed in Table 4) showed that corrugated clippings required more white liquor to cook than did hardwood chips, as evidenced by the higher resultant kappa number with increased percentages of corrugated clippings. The hardwood chip yield was 45.1%. The yield from recooked corrugated clippings averaged 70.3%. Compared to pulp made from 100% hardwood chips, pulp made from 90% hardwood chips and 10% corrugated clippings had a slightly higher kappa number, slightly lower brightness, comparable L, a, and b values, and much less dirt. Handsheet strength improved as the percentage of corrugated clippings increased, as shown in FIG. 5.
Digester Co-Pulping of Corrugated Clippings and Softwood Chips. Two separate digester trials were conducted to investigate co-pulping of corrugated clippings and softwood chips. The first trial examined the effect of recooking one bale of corrugated clippings in a digester with softwood chips. The second trial examined the effect of recooking 3.5 bales of corrugated clippings in a digester with softwood chips. The bales of corrugated clippings were loosened by hand and then manually placed on the chip belt. The clippings were not shredded. The corrugated clippings were placed on a cross haul belt for Trial 1 and on a chip conveyor for Trial 2. The chip screens were bypassed during trial 2. Pulp samples from the blow line sampler and from the final brown stock washer (BSW) were collected, tested and compared to pulp samples collected from digester cooks that did not contain corrugated clippings. These trials showed that cooking one bale and 3.5 bales of corrugated clippings in a digester along with softwood chips had no significant impact on resultant pulp properties.
For Trial 1, the weight of the corrugated clippings was 0.75 ton/digester and the weight of the wet softwood chips was 64.75 tons/digester (est.), giving a weight percentage of 1.2 wt. % corrugated clippings in the digester. The resultant fiber included 0.44 ton/cook from the corrugated clippings and 14.46 tons/cook from the softwood chips, i.e., 3.0% corrugated clipping fiber. For Trial 2, the weight of the corrugated clippings was 2.63 tons/digester and the weight of the wet softwood chips was 62.37 tons/digester (est.), giving a weight percentage of 4 wt. % corrugated clippings in the digester. The resultant fiber included 1.54 tons/cook from the corrugated clippings and 14.04 tons/cook from the softwood chips, i.e., 9.9% corrugated clipping fiber.
Table 5 shows the results for Trial 1. Cook #7 contained one bale of corrugated clippings. Cooks #5 and #6 contained no clippings. There were no significant differences between these cooks, i.e., the kappa number, L, a and b values, dirt counts and handsheet strength properties were all similar.
Table 6 shows the results for Trial 2. Cook #6 contained 3.5 bales of corrugated clippings. Cook #7 contained no corrugated clippings. Both cooks had lower than targeted kappa numbers. Compared to each other, cook #6 and cook #7 were very similar. Cook #6, which had the clippings, had a slightly higher kappa number, slightly lower L value, and lower dirt counts. Handsheet strengths of cook #6 and cook #7 were similar. Compared to the softwood averages for Trial 1, both of cooks #6 and #7 in Trial 2 had lower kappa numbers, higher L values, lower dirt counts and lower pulp strength values. All of these differences were due to cooks #6 and #7 being overcooked.
Pilot Digester Co-Pulping of Boxcuts and Softwood Chips. Wood substitutes other than corrugated clippings were also co-pulped with wood chips. Boxcuts were mixed with softwood chips and the materials were recooked in a pilot digester at various weight percentages. After cooking, the pulp was evaluated for its color and strength properties. Table 7 shows the cook conditions and the pulp quality results for each of four cooks. As seen from the data in Table 7, the cooks involving boxcuts had higher kappa numbers and slightly lower rejects (% shives) than the cook with 100% softwood. The pulp from the 100% softwood furnish and the pulp from the 95% softwood/5% boxcuts furnish had comparable L, a, and b color values and 60-minute ball mill results (see FIG. 6). However, the tensile strength and fiber length were slightly higher for handsheets made of pulp from the 95% softwood/5% boxcuts furnish and the tear strength was about 3-4% lower. The boxcuts had a higher crude yield at 65%, compared to 48% for softwood chips. The handsheet strength test results suggest that the addition of one bale of boxcuts to each softwood chip cook, corresponding to a weight percentage of 1.5%, would have little or no adverse effects on the pulp quality.
Pilot Digester Co-Pulping of Newsprint and Hardwood Chips. In other trial cooks, newsprint was mixed with hardwood chips and the materials were recooked in a pilot digester at various weight percentages. After cooking, the pulp was evaluated for its color and strength properties. Table 8 shows the cook conditions and the pulp quality results for each of six cooks. As seen from the data in Table 8, the cooks involving newsprint had higher kappa numbers and considerably lower rejects than the cook with 100% hardwood. Excluding the 100% newsprint trial, all of the newsprint cooks had lower tensile and tear (0-min. ball mill) strengths than the 100% hardwood cook (see FIG. 7). This arises from the shorter fiber lengths in the newsprint cooks (Kajaani). The L and b color values and the brightness were higher for the newsprint cooks than for the 100% hardwood values. All of the handsheet strength results for the 2.5% newsprint cook are comparable to the values for the 100% hardwood cook. The yields for the newsprint trials were the same as those for the boxcuts trials (newsprint--65%; hardwood--48%). The handsheet strength test results suggest that the addition of one bale of newsprint to each hardwood chip cook, corresponding to a weight percentage of 1.5%, would have little or no adverse effects on the pulp quality.
Co-Pulping of Wax-Coated Corrugated Material and Softwood Chips. In accordance with a further aspect of the present invention, the waste cellulosic material to be co-pulped may be wax-coated material, e.g., wax-coated corrugated clippings. When wax-coated corrugated clippings are co-pulped with wood chips (e.g., softwood chips) in a digester, the fat of the wax will be dissolved by turpenes in the black liquor, by pitch dispersant and by defoamer. The wax will also be broken down by heat and sodium hydroxide in the digester. In accordance with the method of the present invention, the wax is washed out in the brown stock washers utilizing a wax dispersant, which is added to the brown stock washers. Alternatively, wax dispersant can be added to the digester or the clippings can be pre-treated with wax dispersant before the clippings are fed to the digester. The wax dispersant used will depend on the specific wax impregnating the clippings.
In accordance with one preferred method, bales of wax-coated corrugated clippings are shredded in both a low-speed shredder and a high-speed shredder. The shredded clippings are then sent to a cuber to be densified. These pellets are then added to the softwood chip pile. The pellets and softwood chips follow the normal path to the digester. The digester parameters will be the same as those for a typical softwood cook. However, the temperatures of the brown stock washers, the screen room and the wet lap machine are increased to keep the wax in a liquified form. All the pulp is wet lapped, i.e., made into large thick folded sheets or rolls still containing a large amount of moisture. The pulp usually contains from 35 to 55% by weight of air dry pulp.
The preferred embodiments of the invention have been disclosed for the purpose of illustration. Variations and modifications of the disclosed preferred embodiments which fall within the concept of this invention will be readily apparent to persons skilled in the art of pulp manufacturing. All such variations and modifications are intended to be encompassed by the claims set forth hereinafter.
TABLE 1__________________________________________________________________________Results of Laboratory Co-Pulping of Corrugated Material (CM) Clippingsand Southern Hardwood (HW) Black Liquor % Total Residual % HW % CM Combined HW CM Combined CM Combined Effective % Total% % Screened Screened Screened Viscosity Viscosity Viscosity HW Kappa Kappa Kappa Alkali CombinedHW CM Yield Yield Yield (cP) (cP) (cP) Number Number Number Na.sub.2 O/liter) Rejects__________________________________________________________________________100 0 42.8 -- 42.8 50.6 -- 50.6 16 -- 16 8.4 0.09100 0 44.4 -- 44.4 59.9 -- 59.9 16.1 -- 16.1 13 0.1875 25 43.1 67.1 49.1 44.5 14.4 33.3 14.9 23.6 17.4 9.9 0.1150 50 40.8 63.8 52.3 37.8 13.9 18.7 13.1 19.1 16.6 13 0.0850 50 40.1 65.2 52.7 38.2 13 26.1 13.1 20.2 17.5 12.4 0.0125 75 39.3 66.7 59.9 31.5 11.3 12.1 12.8 17.2 16.4 7.1 0.040 100 -- 58.7 58.7 -- 6.9 6.9 -- 15.6 15.6 11.5 0.02__________________________________________________________________________
TABLE 2__________________________________________________________________________Laboratory Co-Pulping of CM and Southern HW With Additives orPretreatment Black Liquor Residual % Total Effective % HW % CM Combined HW CM Combined HW CM Combined Alkali % Total% % Screened Screened Screened Viscosity Viscosity Viscosity Kappa Kappa Kappa (g Combined O/HW CM Yield Yield Yield (cP) (cP) (cP) Number Number Number liter) Rejects__________________________________________________________________________50 50 40.6 64.7 52.7 37.4 11.9 17.2 12.8 17.3 14.3 11.2 0.03 Presoaked with Black Liquor50 50 41.6 67.8 54.7 26 8 12.5 12.4 17.3 15.8 14.3 0.03 Presoaked with Black Liquor50 50 41.8 65.3 53.5 36.1 9.2 15.8 13.1 18.2 15.7 11.2 0.13 Presoaked with Black Liquor and 0.05% Anthra- quinone (on o.d. CM)50 50 42.7 68.4 55.5 38.8 11 17.4 13.6 18 16.9 10.9 0.25 Presoaked with Water and 0.05% Anthra- quinone (on o.d. CM)75 25 43.4 68.9 49.7 47 12 30.4 15.4 23.2 17.7 9.9 0.18 Presoaked with Black Liquor75 25 43 65 48.5 44.5 13.2 29.3 14.5 23.9 17.3 9.3 0.11 Presoaked with Water and 0.05% Anthra- quinone (based on o.d. CM)75 25 42.1 69.4 48.9 44.6 12.4 28.4 14.3 22.5 16.9 17.1 0.2 Presoaked with Water and 0.05% Anthra- quinone (based on o.d. CM and wood chips)__________________________________________________________________________
TABLE 3__________________________________________________________________________COOK No. #4 #1 #2 #3 #5WT % SOFTWOOD CHIPS 100% 90% 90% 50% 0%WT % BOX CLIPPINGS 0% 10% 10% 50% 100%__________________________________________________________________________SW RECOOKING RESULTSK No. 28.2 28.3 26.4 17.2 16.8TOTAL YIELD, % 44.5 49.6 49.45 55.2 67CLIPPING YIELD, % -- 95.5 94 65.9 67(ASSUMING A 44.5% WOOD YIELD)BRIGHTNESS 25.6 25.5 24.5 27.2 26.4L value 60.16 59.98 59.92 61.35 60.77a value 5.25 5.08 5.31 4.61 4.58b value 12.8 12.98 12.83 12.28 12.04IA DIRT, PPM 208 423 319 209 205THIL DIRT 781 550 852 332 171SW HANDSHEET STRENGTH RESULTSBALL MILL, MIN. 0 0 0 0 0FREENESS 855 860 860 840 805TENSILE 24.5 17 15.6 16 16.7MULLEN 121 80 74 74 63TEAR 273 315 329 274 250DENSITY 5.8 5.1 5.1 5.5 5.8POROSITY 0 0 0 0 0FIBER LENGTH 2.18 2.22 2.22 2 1.68BALL MILL, MIN. 60 60 60 60 60FREENESS 750 745 750 650 555TENSILE 33.4 31.1 30.1 26.5 23.4MULLEN 166 147 148 127 109TEAR 180 204 183 178 170DENSITY 8.9 8.4 8.6 8.5 8.5POROSITY 17 11 14 38 59FIBER LENGTH 2.03 2.01 1.96 1.79 1.49SW RECOOKING CONDITIONSACTIVE ALKALI, % 20.65% 20.65% 20.65% 20.65% 17.00%COOK TEMP, F. 342 342 342 342 342CYCLE TIME, MIN 115 115 115 115 115__________________________________________________________________________
TABLE 4______________________________________WT % HARDWOOD CHIPS 100% 90% 75% 50%WT % BOX CLIPPINGS 0% 10% 25% 50%______________________________________HW RECOOKING RESULTSK No. 11.8 13.3 16.8 15.1TOTAL YIELD, % 45.1 52.2 49.1 62.3CLIPPING YIELD, % -- 116.1 61.1 79.5(ASSUMING A 45.1% HWWOOD YIELD)BRIGHTNESS 30.3 28.6 27.3 27.3L value 61.92 60.69 59.6 60.5a value 3.76 3.9 4.69 4.3b value 9.55 10.03 10.05 11.5IA DIRT, PPM 1943 783 559 188THIL DIRT 253 165 117 27HW HANDSHEET STRENGTH RESULTSBALL MILL, MIN. 0 0 0 0FREENESS 820 800 820 800TENSILE 12.2 14 13.2 15.1MULLEN 33 45 46 57TEAR 89 135 162 216DENSITY 5.3 5.7 5.4 5.6POROSITY 0 0 0 0FIBER LENGTH 0.72 0.73 0.75 0.79BALL MILL, MIN. 60 60 60 60FREENESS 625 630 600 530TENSILE 33.4 31.1 29.3 26.3MULLEN 153 143 132 118TEAR 131 152 160 157DENSITY 9.8 9.6 9 8.9POROSITY 49 42 45 62FIBER LENGTH 0.64 0.67 0.71 0.75HW RECOOKING CONDITIONSACTIVE ALKALI, % 16.00% 16.00% 16.00% 16.00%COOK TEMP, F. 344 344 344 344CYCLE TIME, MIN 115 115 115 115______________________________________
TABLE 5______________________________________Trial Results from Recooking 1 Bale Corrugated Clipping withSoftwood Chips______________________________________Cook No. #5 #6 #7______________________________________Digester No. 3 2 1Bales Corrugated Clippings 0 0 1% Active Alkali 16.6 16.6 16.6Top Temperature 340 343 340H-Factor 1000 1000 1000Species SW SW SW______________________________________Digester BSW Digester BSW Digester BSW______________________________________K Number 25.0 22.1 25.6 22.6 26.1 22.9L Value 59.26 61.8 59.49 61.47 59.20 61.30a value 4.88 4.69 4.92 4.67 5.02 4.75b value 12.40 13.90 12.52 13.07 12.31 13.24Brightness 24.2 26.4 24.4 25.8 24.5 25.5Dirt ImageAnalysisSpeck Count 83 131 80 143 86 86TAPPI, ppm 132 276 134 264 102 129ThilmanyCount 29 37 32 33 -- 37TAPPI, ppm 310 714 333 530 -- 411% Hardwood 0% 0% 1% 1% 2% 1%Refining, 0 0 0 0 0 0minutesFreeness 845 850 850 855 850 850Tensile 17.7 14.5 17.2 15.5 13.5 14.4Mullen 72 93 73 75 63 65Tear 270 271 253 253 286 291Density 5.3 5.0 5.1 5.0 4.8 5.0Porosity 0 0 0 0 0 0Fiber Length 2.20 2.24 2.21 2.22 2.23 2.17Refining, 60 60 60 60 60 60minutesFreeness 670 735 700 750 680 720Tensile 30.6 30.5 28.9 29.3 28.2 29.0Mullen 135 149 142 148 133 142Tear 162 186 153 169 171 177Density 9.3 8.8 9.3 8.9 9.0 8.9Porosity 82 23 50 18 50 29Fiber Length 1.90 1.99 1.95 2.00 1.92 1.91______________________________________
TABLE 6______________________________________Trial Results from Recooking 3.5 Bale Corrugated Clipping withSoftwood Chips______________________________________Cook No. #5 #6 February______________________________________Digester No. 4 3 AverageBales Corrugated Clippings 3.5 0 0% Active Alkali 16.3 16.2 16.7Top Temperature 344 343 --H-Factor 1000 1000 1000Species Softwood Softwood Softwood______________________________________Digester BSW Digester BSW Digester BSW______________________________________K Number 20.5 17.2 17.4 147 23.7 --L Value 60.17 63.60 61.29 64.45 -- 61.16a value 4.67 4.31 4.53 4.05 -- --b value 12.69 13.17 11.96 12.65 -- --Brightness 25.6 28.3 27.0 29.9 -- --Dirt ImageAnalysisSpeck Count 64 62 120 102 -- --TAPPI, ppm 393 226 196 321 -- --ThilmanyCount 16 12 21 20 -- 38TAPPI, ppm 179 111 299 191 -- 417% Hardwood 3% 3 1% 1% -- --Refining, 0 0 0 0 0 0minutesFreeness 835 835 850 855 -- --Tensile 16.4 13.5 14.6 13.3 -- --Mullen 72 60 69 59 -- --Tear 269 295 259 295 -- --Density 5.2 5.4 5.2 5.3 -- --Porosity 0 0 0 0 -- --Fiber Length 2.04 2.06 2.11 2.02 -- --Refining, 60 60 60 60 60 60minutesFreeness 680 700 635 690 -- 700Tensile 24.6 24.3 26.9 25.7 -- 29.4Mullen 118 126 123 122 -- 134Tear 183 196 160 190 -- 181Density 8.8 8.9 9.2 9.1 -- --Porosity 27 43 79 38 -- 46Fiber Length 1.78 1.86 1.65 1.78 --______________________________________ --
TABLE 7______________________________________RESULTS FROM BOXCUT/SWD TRIAL COOKSOD WT % SWD 100% 97.5% 95% 90%OD WT % BC 0% 2.5% 5% 10%______________________________________ACTIVE ALKALI % 21% 21% 21% 21%TOP TEMP, F. 342 342 342 342COOK TIME, MIN 115 115 115 115K No. 21.9 29.8 24 23.9CRUDE YIELD % 47.21% 56.69% 51.79% 50.85%% SHIVES 9.69% 6.23% 6.66% 6.38%HANDSHEETPROPERTIESBALL MILL,0 MINUTESFREENESS 830 860 840 850TENSILE 18.1 12.4 13.8 14.9MULLEN 80 53 63 66TEAR 301 273 311 260DENSITY 5.9 4.6 4.6 5.2POROSITY 0 0 0 0KAJAANI 2.08 2.39 2.16 2.24BALL MILL,60 MINUTESFREENESS 765 740 750 750TENSILE 26.9 25.7 27.7 26.8MULLEN 135 122 141 128TEAR 194 186 187 184DENSITY 8.7 8.5 9.2 9.1POROSITY 21 9 22 38KAJAANI 1.85 2.04 1.9 1.92COLORL VALUE 61.5 58.12 62.7 63.73A VALUE 4.8 5.14 4.43 4.51B VALUE 12.33 14.81 13.77 13.56BRIGHTNESS 27.2 21.3 27.7 28.4______________________________________
TABLE 8__________________________________________________________________________OD WT % HDWD 100% 97.5% 95% 90% 85% 0%OD WT % NP 0% 2.5% 5% 10% 15% 100%__________________________________________________________________________RESULTS FROM NEWSPRINT/HDWD TRIAL COOKSACTIVE ALKALI % 18% 18% 18% 18% 18% 18%TOP TEMP, F. 12.6 342 342 342 342 342COOK TIME, MIN 115 115 115 115 115 115K No. 12.6 13.5 13.1 13.3 13.9 17CRUDE YIELD % 48.63% 47.85% 50.02% 49.96% 51% NA% SHIVES 6.41% 5.03% 1.93% 1.4% 5.4% 0%HANDSHEET PROPERTIESBALL MILL, 0 MINUTESFREENESS 845 820 830 820 800 200TENSILE 9 8.7 8.2 10.8 11 19.8MULLEN 25 25 23 28 30 76TEAR 81 70 73 91 95 181DENSITY 5.2 5.3 5.1 5.2 5.6 8.3POROSITY 0 0 0 0 0 122KAJAANI 0.87 0.66 0.75 0.71 0.67 1.43BALL MILL, 60 MINUTESFREENESS 645 660 670 565 560 190TENSILE 28.8 28.7 24.9 26.2 25.3 19.9MULLEN 125 112 102 107 107 76TEAR 135 134 125 123 124 107DENSITY 9.5 9.5 9.7 9.3 9.3 10.1POROSITY 35 19 17 28 46 1133KAJAANI 0.74 0.57 0.62 0.61 0.58 1.2COLORL VALUE 61.08 67.74 65.18 66.44 66.07 54.96A VALUE 4.47 3.27 3.83 3.72 3.83 2.77B VALUE 10.44 11.46 10.99 11.06 10.74 9.36BRIGHTNESS 28.6 34.5 31.3 33.5 34.2 23.2__________________________________________________________________________ | A method wherein waste cellulosic material is used as an alternative fiber source during chemical pulping to replace a fraction of the wood chips. The waste cellulosic material is fed to the digester along with wood chips. The waste cellulosic material need not be repulped or slurried prior to digestion. The wood chips may be any species of hardwood or softwood. Normal chemical pulping charges, temperatures and cooking times applied in the case of 100% wood chip pulping may be used for the co-pulping of waste cellulosic material and wood chips. Thereafter, the pulp is processed as usual for chemical pulping, including the steps of blowing the digester, washing and thickening the brown stock, and bleaching the brown stock under the normal conditions used for the component co-pulped with the waste cellulosic material. Further screening or cleaning steps may be required to remove debris from waste cellulosic material. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to irons and, more particularly, to an iron having an improved skirt.
2. Prior Art
Currently, irons produced by manufacturers who have the desire and/or need to have a metal/metalized looking skirt use what is known as a "shell" to achieve this look. This shell is typically a metal part which is stamped out in the configuration of the outer profile of the skirt. This shell is then placed over the plastic skirt and fastened by a number of different means and becomes the outer surface appearance. There are several limitations and/or disadvantages to this method. The stamping is typically limited to a very simplistic shape. Complex curves and angles of the skirt effectively limit the design of the stamping as is attributed by all the models currently available with a metal shell for a skirt. In each case, the industrial design of these shells is extremely simple. The stamped shell becomes an additional part which must be procured or fabricated and inventoried, thus increasing product cost. Tooling to fabricate the shell is also necessary and will need constant maintenance and periodic replacement; again increasing product cost. Dimensional fits between the shell and the skirt will always be a concern when you try to get two visual parts to align perfectly. Scrap and/or rework costs will increase as a result of this option. Secondary buffing operations that are necessary on some alternatives must be tightly controlled in order not to damage the coating, thus increasing scrap and costs. Black & Decker (U.S.) Inc. offers an iron for sale with a metal skirt (model F63D, The Classic Iron). In this iron the metal shell doubles as the actual skirt as well as an aesthetic, appearance item.
SUMMARY OF THE INVENTION
In accordance with one embodiment of the present invention, an iron is provided having a housing with a skirt, a soleplate connected to the housing, and means for heating the soleplate. The skirt has a molded body comprised of dielectric material. The body has a downwardly extending perimeter rim. The rim has a metal plating adhered directly onto the rim to give an appearance of a metal skirt.
In accordance with another embodiment of the present invention, an electric iron skirt is provided comprising a body and a coating. The body is made of molded dielectric material. The body has a first section and a second section. The coating is applied only to the second section wherein the coating is not applied to the first section.
In accordance with one method of the present invention, a method of manufacturing a skirt for an iron is provided. The method comprises steps of molding a skirt body from a dielectric material; and applying a coating to the skirt body.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing aspects and other features of the invention are explained in the following description, taken in connection with the accompanying drawings, wherein:
FIG. 1 is a perspective view of an iron incorporating features of the present invention;
FIG. 2 is a cross-sectional view of the skirt shown in FIG. 1;
FIG. 3 is a cross-sectional view similar to FIG. 2 of an alternate embodiment of a skirt;
FIG. 4 is a cross-sectional view similar to FIG. 2 of another alternate embodiment of a skirt; and
FIGS. 5a-5c are cross-sectional views similar to FIG. 2 illustrating an alternate method of manufacturing for a skirt.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to FIG. 1, there is shown a perspective view of an iron 10 incorporating features of the present invention. Although the present invention will be described with reference to the embodiments shown in the drawings, it should be understood that features of the present invention may be incorporated into various different types of alternate embodiments of irons. In addition, any suitable size, shape or type of elements or materials could be used.
The iron 10 generally comprises a soleplate 12, a housing 14, a temperature control knob 16, a spray button 18a and a surge button 18b. The soleplate 12 includes a heating element 13 integrally molded therein. The heating element is electrically connected to electronic circuitry 15 in the rear of the iron and a thermostat 17 connected to the temperature control knob 16. The iron 10 further includes a skirt 20 that is located directly above the soleplate 12. Referring also to FIG. 2, a cross-sectional view of the skirt 20 is shown. The skirt 20 preferably comprises a one-piece body member 21 made of a molded high temperature plastic or polymer material which is also a dielectric. The body 21 has a downwardly extending perimeter rim 22 along its two elongate sides and its rear side. In the embodiment shown, the rim 22 has been plated with a chrome plating 24. The chrome plating 24 extends along the outside surface 26, the inside surface 28, and the bottom surface 32 of the rim 22. The chrome plating 24 is adhered directly to the body 21. As evident in FIG. 1, the top side 38 and bottom side 40 of the skirt body 21 are covered by the housing 14 and the soleplate 12, respectively. Thus, only chrome plated portions of the iron 22 are visible to the user.
The method of chrome plating preferably comprises a series of chemical cleaning steps whereby the plastic skirt body 21 is prepared for the chroming process. After the chemical cleaning steps are complete, a copper strike or layer is applied to substantially cover the entire body 21. Application of the copper layer on a plastic substrate is necessary to the chroming process in order to have the chrome permanently plated onto that surface. A laser is then used to scribe or burn lines through the copper layer, down to the body 21, at areas 34 and 36 on the top side and bottom side of the skirt. Thus, scribe lines are formed through the copper layer at areas 34 and 36. The chroming process is then accomplished by clamping electrodes on the copper at the rim 22 outside of the scribe lines. In the chroming process, chrome will be deposited only on those surfaces containing copper that are electrically connected to the electrodes (i.e.: that are on the outside of the scribed lines). The surfaces containing copper which are on the inside of the scribe lines at areas 34 and 36 are not electrically connected to the electrodes because of the electrical break at the scribe lines. The copper inside the areas 34, 36 are chemically etched away during the chroming process leaving only the plastic material of the body 21 again. This is along a majority of the top side 38 and bottom side 40 of the body 21.
The process of scribing and coating only selected areas is done for two reasons. First, by eliminating the copper in selected areas, such as the underside of the skirt, we eliminate the need for electrically insulating all the electrically conductive materials located beneath the skirt. This electrical insulation would be necessary since chrome is electrically conductive and there are regulatory requirements to maintain certain gaps between electrical/electrically conductive components. Since the scribing and subsequent chroming processes prevent any conductive material from getting where you do not want it, you eliminate the need for costly electrical insulation. Second, by eliminating the copper in selected areas, such as the top and bottom of the center section of the skirt where it is not visible to the consumer, you eliminate additional chrome material. Thus, the cost is reduced. The result of the chroming process on the plastic skirt body is a completed one-piece part void of any need for secondary operations.
This invention has several advantages. It eliminates the need for a metal/metallic shell to provide a highly polished surface. It adds no additional costs for tooling. It allows for complex shapes of the skirt since the plating is adhered directly to the skirt body. Dimensional fit issues are non-existent since the plating is extremely thin and is applied directly to the skirt. No secondary buffing operations are necessary.
Some alternative embodiments include the following alternatives. Areas of the body could be masked off, rather than laser scribed, for areas of the body that you do not want to have chrome plated. Another alternative could include chrome plating the entire skirt and electrically insulating all necessary electrical components to comply with regulatory requirements. FIG. 3 shows a cross-sectional view of such an alternate embodiment wherein the body 21 has a chrome plating 24a on the entire skirt. A metal shell could be used and fixedly attached on the skirt body. Rather than chrome plating, the skirt body could be sprayed with a high temperature silver or metal-looking paint that is electrically non-conductive. FIG. 4 shows a cross-sectional view of such an alternate embodiment wherein the body 21 has a sprayed or dipped layer of electrically non-conductive paint 24b.
FIGS. 5a-5c illustrate a further alternate embodiment wherein a vacuum metalizing process is used to deposit a metal such as aluminum on body member 21 of skirt 20. Initially, as illustrated in FIG. 5a, a base coat 25a is applied to rim 22 of body member 21. The base coat is preferably a high temperature reflector urethane resin, identified by Redspot Paint & Varnish Co., Inc. as resin SM2113R2. The top and bottom surfaces of member 21 are preferably masked so that only rim 22 is coated. The base coated skirt is baked at an elevated temperature to dry and cure the coating. The baking temperature is within a range of 250°-300° F. and preferably is about 275° F. The baking time is about 2 hours.
After baking and curing, a metal 25b is deposited on the coated rim 22. The metal is preferably aluminum and is deposited via a standard vacuum metalizing process.
A urethane top coat 25c is then sprayed or otherwise deposited on the coated rim 22. The skirt is then rebaked at an elevated temperature to dry and cure the top coat. The baking temperature is within a range of 155-190° F. and preferably is about 170° F. The baking time is about one hour.
It should be understood that the foregoing description is only illustrative of the invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the scope of the invention. Accordingly, the present invention is intended to embrace all such alternatives, modifications and variances which fall within the scope of the appended claims. | An iron having a housing with a skirt, a soleplate, and a heating element in the soleplate. The skirt has a molded body comprised of dielectric material. The body has a downwardly extending perimeter rim. A metal plating is adhered directly onto the rim to give an appearance of a metal skirt. The rim includes a base coat, the metal layer and a top coat. The base and top coats on the skirt being baked at particular temperatures and for particular amounts of time for curing and drying. | 3 |
[0001] This invention acts to prevent damage to footwear worn by a motorcycle rider which is caused by shifting the transmission of the motorcycle.
BACKGROUND OF THE INVENTION
[0002] To date, motorcycles are equipped with a manually shiftable gear transmission. Typically, shifting of the transmission is done by manipulation of a lever with a foot of the driver. Motorcycle transmission levers are, to date, universally on the left side of the transmission case, so it is manipulated with the left foot. The gear shift lever is positioned so the gear shift lever is engaged by the top of the rider's foot, at a location adjacent or rearward of the knuckle of the big toe. The left shoe or boot of a motorcycle rider is accordingly worn in a characteristic pattern by manipulating the gear shift lever.
[0003] A simple footwear protective device that is widely used by practical motorcycle riders is simply a large athletic sock that is big enough to pass over the rider's footwear. Often, the rider cuts the sock to leave a band of fabric of 3″ or so wide, or of sufficient width to extend from about the knuckle of the big toe to or intermediate any shoe lacings. There are many problems with socks as shoe protectors. They don't stay on the foot well at all because the only thing holding them on is the elasticity of the sock fabric and because they tend to roll up. Socks used in this manner quickly become unsightly because they get so dirty they cannot be washed and they unravel.
[0004] In response to this problem, a number of footwear protective devices have been proposed in the prior art, as shown in U.S. Pat. Nos. 5,168,644; 5,855,078; 5,873,185 and 6,286,234. A similar structure is found in U.S. Pat. No. 3,126,651.
SUMMARY OF THE INVENTION
[0005] The motorcycle riding universe, like most others, is not a monolithic group in which all are alike. There is a segment of rough and tumble types, a segment of older middle class riders, a segment of riders of what are known as sport bikes, and others. In one sense, this invention is aimed at sport bike riders. Sport bike riders are characterized by being well dressed and being interested in the appearance of both the motorcycle and the rider and are accordingly a natural group of buyers of footwear protective devices to prevent damage to the rider's left boot or shoe.
[0006] In this invention, a footwear protective device comprises a sole of water impermeable material, an upper of bodily flexible material and a strap for holding the device on the user's footwear. The sole is preferably of rubber like material and is relatively stiff compared to the upper. The sole accordingly makes the device quite durable. The sole extends rearwardly on the rider's footwear to a location short of the heel of the rider's shoe or boot. The sole is preferably rather thin so the rider can walk with the footwear protector in place without noticing it is being worn.
[0007] The upper is preferably a fabric which tends to shed water and provides for air circulation around and/or through the protective device. In a preferred embodiment, an open toe allows air passage through the protective device cooling the rider's foot and allowing the upper to dry if it has become wet. The open toe also provides considerable flexibility so the upper conforms to shoe or boots of different design. The preferred embodiment also preferably provides a layer of insulation, at least on the side facing the transmission which acts to keep the rider's foot cool during long rides. Other embodiments provide greater air circulation and less insulation. The strap is designed to hold the protective device comfortably on the rider's footwear with a minimum of bother.
[0008] It is an object of this invention to provide an improved protector that is used to prevent damage to footwear of a motorcycle rider.
[0009] A further object of this invention is to provide a footwear protector for motorcycle riders which is inexpensive, durable, washable and acts to prevent damage to the rider's gear shifting shoe or boot.
[0010] Another object of this invention is to provide a footwear protective device that may be made of different colors and/or different textures to provide an attractive accessory for a motorcycle rider.
[0011] These and other objects and advantages of this invention will become more apparent as this description proceeds, reference being made to the accompanying drawings and appended claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a top view of a footwear protective device of this invention;
[0013] FIG. 2 is a front view of the footwear protective device of FIG. 1 , showing an adjustable strap splayed outwardly so it can be seen;
[0014] FIG. 3 is a side view of the footwear protective device of FIGS. 1 and 2 ;
[0015] FIG. 4 is a cross-sectional view of the footwear protective device of FIG. 1 , taken along line 4 -- 4 , as viewed in the direction indicated by the arrows;
[0016] FIG. 5 is an enlarged cross-sectional view of the footwear protector of this invention, taken substantially along line 5 -- 5 of FIG. 1 , as viewed in the direction indicated by the arrows;
[0017] FIG. 6 is a top plan view of another embodiment of this invention;
[0018] FIG. 7 is a top plan view of another embodiment of this invention; and
[0019] FIG. 8 is a top plan view of another embodiment of this invention.
DETAILED DESCRIPTION
[0020] Referring to FIGS. 1-5 , a footwear protective device 10 of this invention is illustrated. The device 10 comprises, as major components, a sole 12 , an upper 14 and an adjustable strap 16 for securing the device 10 to a motorcycle rider's boot or shoe 18 . The motorcycle rider's boot or shoe 18 is of conventional type including a sole 20 , a heel 22 , and an upper 24 . As will be more fully apparent hereinafter, an important feature of this invention is the sole 12 of the device 10 terminates substantially forward of the heel 22 of the rider's footwear 18 .
[0021] The sole 12 is made of a durable, water impermeable material typical of shoe soles in general, such as leather, soft plastic, rubber or the like and is preferably a pair of thin flat rubber or rubber like sheets or sections 26 , 28 . As shown best in FIG. 5 , the upper 14 is sewn to the uppermost sole section 26 by a row of stitches 30 and the sewn assembly is glued or otherwise attached to the lowermost sole section 28 . As will become more fully apparent hereinafter, the sole 12 is considerably more rigid than the upper 14 and is of the same order of stiffness as normal shoe soles.
[0022] The upper 14 is made of a bodily flexible material, preferably a pair of fabric layers 32 and an interior foam insulating layer 34 as shown in FIG. 5 . The fabric layers 32 are preferably smooth and inelastic so the device 10 more easily slips onto the footwear of the rider. The foam layer 34 provides thermal insulation thereby minimizing heat transfer from the transmission to the rider's foot. As shown in FIGS. 1-4 , the upper 14 is made of a central panel 36 and two lateral panels 38 , 40 sewn together along seams 44 , 46 . It will accordingly be seen that the upper 14 provides a rearwardly open receptacle receiving the forward end of the rider's footwear as shown in dashed lines in FIG. 3 . Preferably, the upper provides an open toe 50 allowing air to flow through the receptacle, around the rider's footwear thereby cooling the rider's foot and promoting rider comfort. Suitable sewn seams 52 , 54 terminate the edges of the upper 14 in a conventional manner.
[0023] The adjustable strap 16 may be of any suitable type or configuration to secure the protective device 10 to the rider. A preferred arrangement is shown in FIGS. 1-4 where the strap 16 includes a first section 56 attached to one side of the upper 14 and a second section 58 attached to the other side of the upper 14 . The first strap section 56 includes a long piece 60 sewn to the upper 14 and extending generally parallel to the sole 12 . A short diagonal piece 62 sewn to the long piece 60 and to the upper 14 at a location above the terminus of the long piece 60 . A pair of hood-and-loop connectors 64 are provided to tie down the end of the long piece 60 as will become more fully apparent hereinafter. The strap 16 is adjustable in any suitable manner, as by making the connectors 64 of considerable length, as will become more fully apparent hereinafter.
[0024] The second strap section 58 includes a first piece 66 sewn to the upper 14 and generally parallel to the sole 12 . A second shorter diagonal piece 68 is sewn between the upper 14 and the first piece 66 . A pair of D-rings 70 are sewn into the end of the first piece 66 so the end of the strap section 56 can be looped through the D-rings 70 . By passing the end of strap section 56 through the D-rings 70 so the connectors 64 abut, a loop is formed by the strap 16 around the back or heel of the upper 24 of the footwear 18 shown in FIG. 3 . The size of the loop is adjustable because the connectors 64 are of considerable length and thus can be overlapped to one degree or other. It will be seen that the loop lies along a line 72 on the back of the footwear 18 and the sole 12 terminates well forward of the heel 22 . Thus, the sole 12 terminates about midway between the toe end of the device 10 and the heel 22 , by which it is meant that the sole 12 extends between about 30-70% of the distance between the toe end of the device 10 and the line 72 . As seen best in FIGS. 1-4 , the pieces 62 , 68 may comprise opposite ends of a length of strap passing under and sewn to the seam 54 .
[0025] Use of the footwear protective device 10 should now be apparent. The rider puts his left foot into the receptacle provided by the upper 14 so the toe of the shoe or boot 18 extends to or through the open toe 50 . The strap 16 is threaded through the D-rings 70 to provide a loop extending around the heel of the rider's shoe 18 and then cinched up. The upper 14 covers the area from the rider's big toe and to where the rider's leg begins. Thus, as shown in FIG. 3 , there is plenty of room and plenty of material to abut and manipulate the gear shift lever 74 . It will be seen that the upper 14 is perforate to allow easy air flow through the receptacle and around the rider's footwear 18 .
[0026] Referring to FIG. 6 , there is illustrated another embodiment of a footwear protective device 76 of this invention. The device 76 is substantially identical to the device 10 except the upper 78 is made of a combination fabric/foam insulating material 80 on the left and a large mesh fabric 82 on the right. The material 80 provides protection to the rider's footwear and the mesh fabric 82 supports the edge of the material 80 and provides for air circulation around the rider's footwear.
[0027] Referring to FIG. 7 , there is illustrated another embodiment of a footwear protective device 84 of this invention. The device 84 is substantially identical to the device 76 except the mesh fabric 82 has been replaced by a series of straps 86 sewn to the sole. The combination fabric/foam insulating material 88 provides protection to the rider's footwear and the straps 86 support the edge of the material 88 and provide for air circulation around the rider's footwear.
[0028] Referring to FIG. 8 , there is illustrated another embodiment of a footwear protective device 90 of this invention. The device 84 is substantially identical to the device 76 except the upper 92 comprises a large mesh fabric 94 spanning the sides of the sole 96 and a leather or heavy vinyl pad 98 bonded to the mesh fabric 94 . The pad 98 provides protection to the rider's footwear and the mesh fabric 94 supports the pad 98 and provides air circulation around the rider's footwear. The device 90 conveniently provides an open toe assisting the mesh fabric 94 to conform to the shape of the rider's footwear.
[0029] Referring to FIG. 9 , there is illustrated another embodiment of a footwear protective device 100 of this invention having a sole 102 , an upper 104 and an adjustable strap 106 . The device 100 may be substantially identical to any of the devices 10 , 76 , 84 , 90 except the strap 106 is designed to pass under the rider's footwear 108 rather than past the rider's heel. Most shoes and boots with heels 110 have soles 112 that are slightly concave thereby providing a recessed location 114 for the strap 106 . The strap 106 provides a pair of legs 116 , 118 connected to spaced locations on the upper 104 . One of the legs 116 includes one or more D-rings 120 for receiving an end of a strap section 122 connected in a similar manner to the opposite side of the device 100 .
[0030] It will be seen that the soles of the various footwear protective devices 10 , 76 , 84 , 90 , 100 are generally flat in the sense that the soles lack a heel of a thickness greater than the heels 22 , 110 of the shoe or boot with which the protective devices are used. Partially for this reason, a rider can walk wearing the protective devices and not be aware of wearing them.
[0031] Although this invention has been disclosed and described in its preferred forms with a certain degree of particularity, it is understood that the present disclosure of the preferred forms is only by way of example and that numerous changes in the details of operation and in the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as hereinafter claimed. | A device for protecting footwear of a motorcycle rider comprises a sole of a water impermeable material, an upper of bodily flexible material and an adjustable strap for securing the device to footwear of the rider. The device is typically worn on the left foot of the rider because motorcycle transmissions are shifted by the left foot, leaving a characteristic wear pattern on the left shoe or boot of the rider. The upper allows substantial air movement around the rider's footwear and may be partially or wholly insulated with a foam layer in the upper. Some embodiments provide greater air circulation and less insulation. Two types of adjustable straps are shown. | 0 |
This is a continuation of application(s) Ser. No. 08/533,318 filed on Sep. 25, 1995 and which designated the U.S. Pat. No. 5,667,754.
FIELD OF THE INVENTION
The field of the present invention relates to tests for determination of Chemical Oxygen Demand (COD) in aqueous samples. More particularly, it relates to a method of removal of chloride ion from COD test samples, so that the chloride ion does not cause an erroneous high sample reading.
BACKGROUND OF THE INVENTION
Oxygen demand is an important parameter for determining the effect of organic pollutants on receiving water. As microorganisms in the environment consume these materials, oxygen is depleted from the water. This can have an adverse effect on fish and plant life.
There are three main methods of measuring oxygen demands: directly, by biochemical oxygen demand (BOD) and/or chemical oxygen demand (COD), and indirectly by total organic carbon (TOC) procedures. BOD, because it uses microorganisms for oxidation, gives the closest picture of the biological processes occurring in a stream. However, results are not available for five days, and the BOD test is inadequate as an indicator of organic pollution when used with industrial waste water containing toxic materials which poison the microorganisms and render them unable to oxidize wastes.
Unlike BOD, the two other methods do not use biological processes, and are therefore faster and not affected by toxic materials. A strong oxidizing agent or combustion technique is used under controlled conditions in the TOC method to measure the total amount of organic material in a sample. The results obtained may not be as accurate as the results reached through the COD or BOD method in predicting environmental oxygen demand because oxygen demands may differ between compounds with the same number of organic carbons in their structures. The difference in oxygen demand between two compounds containing the same amount of organic carbon can be seen in the following equations showing the oxidation of oxalic acid and ethanol: ##STR1##
Each molecule of ethanol uses up six times as much oxygen as an equivalent amount of oxalic acid, and thus would have a much greater effect on the dissolved oxygen present in a receiving water. Estimating environmental oxygen demand (as with BOD and COD) requires complete oxidation of carbon and hydrogen present in the organic matter. Thus, while TOC is a more direct expression of total organic content than BOD or COD, it does not provide the same kind of information. An empirical relationship can exist between TOC, BOD and COD, but the specific relationship must be established for a specific set of sample conditions.
Currently, the COD test has a fairly specific and universal meaning: the oxygen equivalent of the amount of organic matter oxidizable by potassium dichromate in a 50% sulfuric acid solution. Generally, a silver compound is added as a catalyst to promote the oxidation of certain classes of organics. Typically, a mercuric compound may be added to reduce interference from the oxidation of chloride ions by the dichromate which will give false high COD readings. The end products of organic oxidations are carbon dioxide and water.
After the oxidation step is completed, the amount of dichromate consumed is determined either titrimetrically or calorimetrically. Either the amount of dichromate reduced (Chromium III) or the amount of unreacted dichromate (Chromium VI) remaining can be measured. If the latter method and colorimetry are chosen, the analyst must know the precise amount of dichromate added and be able to set the instrument wavelength very accurately, since readings are routinely taken on the "shoulder" of the Chromium VI absorbance peak. Wavelength settings must be reproduced precisely in order to avoid errors when using a previously generated calibration curve.
Dichromate was first used in the COD test over 50 years ago. Before that time, potassium permanganate was the oxidant of choice. Analysts have tried many other reagents, such as potassium persulfate, cerium sulfate, potassium iodate and oxygen itself. Generally these other oxidants have not been satisfactory.
A prior case of this same inventor; U.S. Ser. No. 08/475,187, filed Jun. 7, 1995, and entitled "Manganese III Method For Chemical Oxygen Demand Analysis", relates to a new COD test that eliminates the use of dichromate in sulfuric acid and replaces it with another COD test reagent containing Mn +3 ions and of improved performance. The subject matter of that application is incorporated herein by reference.
As mentioned previously, the current state of the art involves the addition of mercuric compounds added to reduce interference from the oxidation of chloride ions by the dichromate. The addition of mercuric salts, while satisfactory to eliminate interference from chloride ion in aqueous COD samples, is itself unsatisfactory because mercury is a pollutant and known toxicant, which makes it undesirable for use in COD analysis. Mercury has its own polluting and environmental risks. There is, therefore, a present and continuing need for the development of a means of removing potentially interfering chloride ions from aqueous COD samples which avoids use of mercury salts, and which does not in any way interfere with the accuracy of the COD analytical procedure. This invention has as its primary objective the fulfillment of this need.
An additional objective is to provide a cartridge device which can be provided in a kit for chemical COD analysis that can be conveniently used by operators to conduct a pretreatment chloride removal step prior to analysis of an aqueous COD sample.
The method and means of accomplishing each of the above objectives will become apparent from the detailed description of the invention which follows.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective and exploded view of the cartridge of the present invention with the inner and outer sections aligned for mating relationship.
FIG. 2 shows the inner and outer sections in mating relationship.
FIG. 3 shows in cross section a complete cartridge unit inserted in a test tube.
FIG. 4 shows a bottom view of the inner cartridge.
FIG. 5 shows a bottom view of the outer cartridge.
SUMMARY OF THE INVENTION
The invention relates to a method of pretreating aqueous COD samples to remove interference from chloride ions. Bromide and iodide ions are also removed, but they are not normally present in aqueous COD samples in concentrations high enough to constitute significant interference. In the method, the aqueous sample is acidified with a mineral acid, preferably sulfuric acid, and then passed through a source of bismuthate or other pentavalent Bismuth-containing ion or compound, preferably in solid form. After this pretreatment the sample is then used for COD analytical testing. In another aspect of a related invention, the process is conducted using inner and outer cartridges adapted to matingly fit within each other to form a cartridge unit. Both cartridges are made of materials that are inert to acidified test samples, any chloride present or chlorine generated, and not retain any organics present in the test sample and have open upper ends and a porous lower end. The outer cartridge contains solid form sodium bismuthate which may be mixed with a filter aid, and the inner cartridge contains a removable filter which may be removed and added to the COD test sample so that solid organics filtered out during the pretreatment process are recombined with the liquid portion of the sample so that the COD test results represent the total of soluble plus insoluble organic compounds and/or mixtures, yielding a test result representative of the total COD of the sample.
DETAILED DESCRIPTION OF THE INVENTION
In accordance with the process of this invention, a typical aqueous COD test sample is pretreated to remove interference from chloride ion. The pretreatment involves materials which avoid the conventional prior art treatment with mercury salts as used to complex chloride ion and render it unavailable for reaction in the COD test. In the present process the pretreatment involves reacting an acidified aqueous COD sample with a source of bismuthate ion or other pentavalent bismuth source.
The source of bismuthate or pentavalent bismuth ion is not critical, and it may be bismuth tetroxide, bismuth pentoxide, free bismuthic acid, or, more preferably, a Group I or Group II bismuthate salt. The most preferred are Group I bismuthate salts, and particularly sodium bismuthate and potassium bismuthate. In the process of the reaction, the Bi +5 is reduced by any chloride ion to Bi +3 and the chloride ion is oxidized to free chlorine. In this way, the chlorine escapes as the free gas.
While the bismuthate ion may be added as an aqueous solution since it has some level of solubility, it is much preferred that it be used in solid form as explained below. Since the bismuthate reaction with chloride ion is believed to be a surface reaction, the reaction is facilitated if the bismuthate, for example, in the form of solid sodium bismuthate, is mixed with a filter aid to increase available surface area of the bismuth compound for reaction with chloride and facilitate flow of the liquid sample through the matrix. Any such filter aid, if used, must be inert to acidified test samples, any chloride present or chlorine generated, and not retain or contribute any organic compounds. Numerous filter aids are available and can be used, but the most preferred are inert high-density glass beads of 40 micron average size. Suitable glass beads are obtained from 3M and sold under the trademark Empore™ 400.
It is preferred that a mixture of the bismuthate ion or pentavalent bismuth source, such as sodium bismuthate, and the inert filter aid be 1:1 on a volume basis. While this is not critical, a 1:1 relationship does seem to perform satisfactorily in that it allows the acidified test sample to freely flow through the solid form bismuthate reagent, while at the same time providing intimate contact. Other ratios have been tested and found to be satisfactory, and may be desirable due to cost or other important factors. It is conceivable that other inert filter aids such as clays like diatomaceous earth, etc., may be employed as well.
The aqueous COD sample is acidified prior to contacting it with the solid form bismuthate or other pentavalent bismuth source. Any non-halogen mineral acid is suitable, such as sulfuric, phosphoric or nitric acids. The acid concentration for sulfuric acid should be within the range of from 3% to 50%, and generally from 8% to 25% is preferred. This corresponds to normalities of from about 1 normal to 18 normal, and preferably from 3 normal to 9 normal. The current procedure operates at about 10% sulfuric acid (approximately 3.5 normal to 4 normal) which is easily obtained by combining 1 part concentrated sulfuric acid, with 9 parts of sample. If the acid is more dilute than about 1 normal, the bismuthate oxidation-reduction reaction will not occur fast enough, and if it is much more concentrated than 18 normal, the bismuthate or pentavalent bismuth will attack organic compounds either directly or through the generation of intermediate oxidizing agents.
Applicant does not wish to be bound by any theory of operation, but notes that it is surprising that chloride is selectively oxidized in the presence of organics which one might also expect to be oxidized but apparently are not. It is believed that the reaction occurs on the surface of the bismuthate compound particles.
The pretreatment step can be conducted in a variety of ways, but the preferred way is in conjunction with the cartridge unit herein described. In this way there is a pretreatment with solid form bismuthate in a manner that does not remove any organics, which of course need to be retained in order to get an accurate COD analysis.
Turning to FIG. 1, it shows the device in perspective and exploded view. The device or composite cartridge unit 10 is comprised of an outer cartridge 12 and an inner cartridge 14. Looking first at outer cartridge 12, it has an open top end 16 and a perforated bottom end 18 joined by circular wall 20 to form a cylindrical shape. Top end 16 has a shoulder portion 22 and rim 24. Positioned over the perforated bottom end 18 is fixed porous filter 26 (see FIG. 2) and held in place in some manner such as a press fit or welded configuration. Positioned on filter 26 is a mixture of solid form bismuthate and filter aid 28. Positioned on or above mixture 28 is a fixed porous filter 30.
The inner cartridge 14 has an open top 32 and a perforated bottom 34, joined by a similar circular wall 36. Positioned on perforated bottom 34 is a removable press fit porous filter 38. The diameter of inner cartridge 14 is such that it can matingly fit inside of the open top 16 of outer cartridge 12 encapsulating the reagent mixture 28 as shown in FIG. 2. Outer cartridge 12 can then be inserted in the top of test tube 40 as illustrated in FIG. 3.
Both outer cartridge 12 and inner cartridge 14 are made of materials that are inert to the acidified sample and reaction products such as chlorine gas. Numerous materials can be employed, but a very suitable inert material is polypropylene. Other polymeric alpha olefins such as polyethylene could also be utilized. The precise material is not critical, as long as it is inert to the acidified sample and reaction products. Filter 38 must additionally be inert to the COD reagent under test conditions (oxidizing acid media at elevated temperature).
In actual operation, the analytical test using the outer and inner cartridges containing the reagent and filters assembled together as a unit 10 is conducted in the following manner. A test sample is mixed with the mineral acid, preferably sulfuric acid, to the concentrations previously specified. The COD test reagent, the prior art dichromate reagent or the Manganese III reagent of the previously incorporated by reference Miller application, is placed in test tube 40. A 0.60 milliliter sample of the aqueous COD material diluted 1:9 with the sulfuric acid solution previously referred to is inserted into the open mouth or top of the previously-described cartridge unit 10. The test tube 40 is then, for example, placed in a centrifuge and centrifuged to draw the acidified aqueous COD sample through press fit filter 38, the perforated bottom 34 of cartridge 14, the fixed filter 30, through the mixture of bismuthate and filter aid 28, through fixed filter 26, perforated bottom 18 of cartridge 12 and down into test reagent 42 in test tube 40. As the acidified aqueous COD sample is pulled through the cartridge unit by centrifugal action, the previously referred to oxidation-reduction reaction occurs. Bismuthate Bi +5 is reduced to Bi +3 ion, and chloride (Cl - ) is oxidized to free chlorine which escapes as a gas. As can be seen, any chloride ion is removed by the process. In order to recover any organics that may have been removed as solid particles by filter 38, it is removed from inner cartridge 14 and added to the reagent 42 in test tube 40. Thereafter the COD analysis occurs in conventional fashion.
The amount of time that the acidified aqueous COD sample is in contact with the reagent in the cartridge must be adequate for the reaction to occur. The amount of time for the centrifugation must be adequate to both allow time for the reaction to occur and for the sample to pass as completely as possible through the cartridge and the reagent it contains. The rate at which the sample flows through the cartridge is also a function of the pore size, thickness and composition of the filters selected for the cartridge unit. Filters composed of glass fiber or polymeric materials have been found to be suitable, provided they are inert to acidified test samples, any chloride present or chlorine generated, and not retain or contribute any organic compounds. A restriction on filter 38 is that it must be inert to the digestion process that occurs in solution 42 in test tube 40. An additional restriction on filters 26 and 30 is that they must be inert to the bismuthate reagent 28.
The rate is also a function of the design of the centrifuge unit, specifically, the radius of the arc traveled by the unit in the test tube and the rate of travel (rpm), which together dictate the g-force on the unit and the sample it contains. When centrifugation is employed, suitable results can be obtained in a fixed time between 1 and 5 minutes, depending on the design of the centrifuge, the rpm setting as previously described and the composition of the filters. An Eppendorf Model 5416 centrifuge gave satisfactory results when samples were spun at 2500 rpm for 3 minutes. Equally satisfactory results were obtained using a 2-step centrifugation process where the first step occurs at a slower speed and duration (500 rpm for 2 minutes) adequate to allow time for the aqueous solution to be in contact with the bismuthate, and a second step which utilizes a higher speed (2500 rpm for 1 minute) to force as much of the aqueous sample out of the cartridge unit and into the test tube as possible. The 2-step centrifugation has different flow requirements than the previously described single-step process, and, hence, uses a different combination of filter materials, typically glass fiber filters only, though some polymer filters may also be acceptable.
Filters 26 and 30 have been described here as separate pieces, but it is possible for both inner cartridge 14 and outer cartridge 12 to have integrally welded filters. With respect to inner cartridge 14, filter 30 would be positioned above perforated bottom end 34 and below press fit filter 38. The preferred method of forcing aqueous COD samples through the cartridge is by centrifugation. Equally satisfactory results were obtained with vacuum filtration. In this method, the sample would be pulled via vacuum through the solid bismuthate. Another alternative is to force the acidified aqueous sample through the cartridge under pressure.
The following examples are offered to further illustrate, but not limit, both the process and the device of the present invention. In the test as outlined below, in order to test efficacy of chloride removal, a blank containing no chloride was used, and thereafter, controls with added amounts of 200 ppm of chloride, 500 ppm of chloride and 1000 ppm of chloride were made. The blank was COD tested using a Hach Company Model DR3000 spectrophotometer and an average value for 9 trials was obtained of 1.470 absorbance. Thereafter, the known test samples containing 200 ppm, 500 ppm and 1000 ppm of chloride were tested. Absorbance readings were thereafter taken. Generally, for the Hach system as the absorbance reading goes down, the COD value increases. Thus, the objective is to keep the reading as close as possible to the blank. If this is accomplished, it shows that the chloride is not interfering to give a false high reading.
In accordance with the process, cartridges were prepared as previously described. Outer cartridge 12 contained 0.2 cubic centimeters of sodium bismuthate mixed with filter aid on a 1:1 volume ratio. Concentrated sulfuric acid, 36 normal, and samples were mixed in a 1:9 ratio, and 0.6 ml of this mixture was pipetted into the inner cartridge 14 of the assembled unit. Thereafter, it was placed in a centrifuge and spun for 2 minutes at 500 rpm followed by 1 minute at 2500 rpm. Thereafter, the press fit filter 38 was taken out and added to the reagent 42 in test tube 40 followed by COD testing using the Hach Model DR 3000 spectrophotometer.
As indicated for the blank sample with 9 trials, the average absorbance value was 1.470. Table I below shows the values of the blank and of five separate measurements for samples containing 200 ppm, 500 ppm and 1000 ppm chloride and one value for each showing the results of testing in the presence of chloride without benefit of the pretreatment process. As can be seen from the table, deviation from the average value for the blank 1.470 was very small as compared to no pretreatment, indicating that chloride had effectively been removed so that there was minimal chloride interference.
TABLE I______________________________________Absorbance Value Value w/o Value Value Pre-Sample Value 1 2 Value 3 4 Value 5 Avg. Treatment______________________________________1 Blank (9 trials were averaged for this 1.470 "blank" value) →2 Cl-200 1.463 1.462 1.423 1.427 1.458 1.447 1.3753 Cl-500 1.443 1.453 1.481 1.459 1.438 1.455 1.2504 Cl-1000 1.435 1.426 1.425 1.423 1.437 1.429 1.075______________________________________
It therefore can be seen that the invention accomplishes at least all of its stated objectives. | A method of pretreating aqueous chemical oxygen demand (COD) samples to remove the risk of potential chloride ion interference. The method comprises acidifying an aqueous COD test sample, and thereafter passing the acidified sample through a source of pentavalent bismuth (Bi 5+ ) such as sodium bismuthate. | 6 |
This application claims priority under 35 U.S.C. § 119(e) for Provisional Patent Application No. 60/273,953, filed Mar. 8, 2001 hereby incorporated by reference.
FIELD OF INVENTION
This application is directed to a method of coating articles such as superalloy turbine parts with a protective coating which may contain several elements, but will generally contain a significant percentage of aluminum.
BACKGROUND OF THE INVENTION
The life of gas turbine parts which are subjected to the passage of the hot gas stream can be extended by bonding a coating of an oxidation resistant material such as an aluminide material to the surface of the part. Considerable research effort has been directed to the selection of the oxidation resistant material and the process for application of the material. This has resulted in the evolution of gas turbine blades which now have a life in the order of thousands of hours (when coated) compared to a life of only a few hundred hours if the same blades were operated in the hot gas stream in an uncoated condition.
Gas turbine parts which are subjected to the passage of the hot gas stream are required to operate in a hostile environment. Not only must these parts, typically turbine blades and vanes, withstand the intense heat produced in the hot gas stream, but both turbines and vanes are required to deflect the hot gas stream to enable the turbine engine to extract energy from the hot gas stream.
Turbine blades are also subjected to substantial centrifugal forces during operation; the coating must not migrate, peel or crack in the presence of any of the above forces during operation of the turbine.
The hot turbine parts are also subjected to the passage of a hot gas stream which usually contains corrosive materials such as sodium, potassium, sulphur and vanadium which may be present in the turbine fuel. Sometimes the turbine may ingest other substances in the intake air such as seawater salt which when heated can become very corrosive.
Similarly the atmosphere contains particles of dust and other foreign particles which when ingested in the turbine and accelerated in the hot gas stream tend to “sand blast” the surfaces of the turbine blades and vanes to erode the surface thereof.
In addition to the above forces, each turbine blade is subjected to pulsations in pressure during turbine operation which cause deflections and vibrations in the blade which the coating must also endure without peeling, spalling or cracking during the lifetime of the blade.
In the past, turbine parts which must operate in the hot gas stream have been successfully coated with selected metals or metal oxides applied to the surface of the superalloy by various techniques which have evolved over the past forty years. Some methods of coating involve vapour deposition; others utilize a pack cementation process; still others use a slurry deposition process in which a carrier in which particles of selected metals are held in suspension so that the mixture of carrier and metallic particles may be applied to a substrate to form a coating on the substrate.
In a slurry process a powder composed of selected metallic particles is typically suspended in a carrier which performs the function of a fugitive binder, and which carrier functions to carry the suspended metallic particles to the cleaned surface of the substrate to be coated. If the selection of components of the mixture is done correctly, the carrier and suspended particles will form a uniform coating on the surface of the substrate and the carrier will temporarily bind the particles of the metallic material to the surface of the substrate (see U.S. Pat. No. 3,102,044 for example). The carrier is then driven off by some means, usually by heating the substrate to a predetermined temperature. If necessary, the coated substrate may then be subjected to additional heat treatment procedures to bond a continuous uninterrupted coating of a protective material to (the surface of) the substrate.
The carrier for the metallic or metallic oxide particles must be capable of keeping the metallic or metallic oxides in suspension during the deposition process so that a continuous, uniform coating of the metallic or metallic oxide materials results. It is important that the coating process may be controlled so that a uniform coating is deposited on the substrate and under no circumstances will any eventual blistering, cracking, peeling or spalling of the coating occur during heat treatment or during subsequent use.
In addition, the coating comprising the carrier and the selected particles suspended therein should be capable of being applied locally to a previously coated substrate to “repair” places during the application process where the previously applied coating has been applied too sparingly, or the coating on the surface has been impact damaged before heat treating of the coated substrate has begun.
Because the carrier for the selected particles which will ultimately become the coating is usually of a somewhat volatile nature, it must be environmentally acceptable in order to be used with this process in safety.
U.S. Pat. No. 3,102,044 Aug. 27, 1963 Joseph
This is one of the earlier coating patents, which describes a process of application of a coating mixture comprising particles of a metal or metal oxides suspended in a carrier to turbine parts.
The selected particles are suspended in a suitable dispersant which may be alcohols, esters and ketones. The carrier is evaporated by some means and the coated article is subjected to a heat treatment operation to diffuse and permanently fix the metallic dust or powder to the substrate.
U.S. Pat. No. 3,248,251 Apr. 26, 1966 Allen
This patent describes a process for coating substrates such as turbine blades with solid particulate materials such as aluminum powder carried in a phosphates/chromates/metal ion solution. The powder-carrier mixture may be applied by spraying, dipping, rolling or brushing to/on the surface of the substrate to be coated.
The coating may be then heat cured and processed to form a protective coating for the substrate.
U.S. Pat. No. 4,310,574
A lacquer slurry comprising cellulose nitrate carrying silicon powder is deposited on a substrate. The slurry was dried on the substrate and the coated substrate was placed on an aluminum powder pack and heated to 1100° C. to produce an aluminized coating.
SUMMARY OF THE INVENTION
Articles such as turbine vanes and blades are cleaned in preparation for coating as in most of the prior art procedures. A slurry is prepared which comprises a carrier of silicone alkyd paint in which an aluminum (or an aluminum alloy) powder (in this instance Amdry 355) is mixed in the paint in a predetermined ratio ranging from 10 to 80% by weight. Additions of other elemental powders ranging from 0-15% of the mixture may also be added to alter the composition of the finished diffusion coating.
After the slurry is mixed and degassed, the viscosity is checked and if the viscosity is suitable, parts to be coated are dipped in the slurry. Parts are allowed to “drip off” from selected edges or points of the dipped parts and the coating is allowed to cure for at least 60 minutes.
The coated parts may be placed in a suitable oven at a temperature less than 100° C. to drive off the solvent materials of the carrier.
The process is completed by subjecting the partially treated coated parts to treatment at high temperature in a vacuum or inert gas atmosphere. At temperature, a reaction with the substrate to form a metal aluminum compound on the surface of the substrate occurs.
DESCRIPTION OF THE INVENTION
Many patents have issued relating to the production of diffused aluminum coatings for metallic turbine parts which are subjected to high temperature operation in hostile environments. Turbine blades and vanes composed of alloys of chromium, cobalt, molybdenum, aluminum, nickel and traces of other elements usually referred to as “SUPERALLOYS” typically operate in such an environment.
It has been found that the working life of such parts may be drastically extended by the presence of a protective coating formed on and diffused into the superalloy. The process of forming such a coating on the superalloy has been the subject of many patents and technical papers.
This application describes a very simple method of providing an aluminum based coating on a substrate such as a SUPERALLOY by means of applying a coating to the SUPERALLOY part at room temperature and atmospheric pressure without the use of complicated cementation heat pack processes or vapor deposition processes.
Parts to be coated (in this instance, turbine blades) are cleaned by sand blasting (i.e. sand blasting with grit 240).
A slurry is prepared as follows: 50 parts of 12 SiAl powder (Amdry 355, fine powder preferably −350 mesh) Id #3550 is mixed into 50 parts of a carrier (1:1 mass ratio).
The preferred carrier is a commercially available paint manufactured by Benjamin-Moore and is available under designation M66-79 silicone alkyd high heat aluminum paint.
The powdered silicon aluminum mixture is slowly added to the M66-79 paint while mixing continues.
The mixture is repeatedly evacuated to −10 psig for several seconds to remove entrapped air (requires 3-4 applications at about 15-20 seconds per application).
Mixing of the paint and powder continues for 30-50 minutes. At this time, no entrapped air should be found in the mixture.
Mixing continues until no air bubbles or agglomerates are present in the mixture (generally requires 2 hours).
Filter the thoroughly mixed slurry through a 0.5 mm mesh screen.
Coating
Dip the partially coated article in the coating mixture for enough time to allow the coating to wet the surface of the part to be coated. Remove the dipped part from the coating mixture.
Allow the excess of the slurry coating to drip from a preselected “drip point” on the coated part.
Allow the coated part to “air cure” for about one hour at room temperature.
At this time, the coated part may be inspected for coating thickness, coating integrity etc. and repairs to the coating by brushing etc. may be done before heat curing and coating diffusion are done.
Diffusion
The “green” coated articles are next placed in a furnace where the pressure is dropped to less than 1 mm Hg and held at this level for about ½ hour (at room temperature).
The furnace is now filled with Argon at room temperature and pressure.
Heat treatment begins with a temperature ramp of 20° C. per minute to about 840° C. while a slow flow of argon gas passes through the furnace to partially form a diffused coating. This temperature is maintained constant for about ½ hour. Allow coated articles to cool to about 100° C. Inspect coated surfaces of articles.
Place the previously treated articles in a high temperature vacuum furnace. Draw a vacuum and heat tie coated parts at a rate of 10° C./minute to 1080° C. Hold this temperature for about ½ hour. Air quench the heated parts.
The result will be a SUPERALLOY part having a protective silicon containing aluminide coating diffused into its surface. The coating displays all the characteristics of prior art aluminide coatings, that is, enhanced oxidation, corrosion and erosion resistance as well as resistance to cracking, peeling and spalling, etc.
The coating technique is simplistic in nature and relatively inexpensive to apply. No exotic vapor deposition, pack cementation or slurry steps are required. Relatively unskilled personnel are able to perform the steps required to obtain a suitably coated part.
Control of the coating process is rather straightforward and relatively easy to maintain.
Coating equipment is not of the exotic nature as found in some prior art schemes.
The coating process tends to be forgiving in that areas which for some reason or other are not covered satisfactorily, may be repaired prior to heat treating by hand brush coating.
The M66-79 silicone alkyd aluminum paint is the preferred carrier for this process. The paint has excellent “leveling” qualities and the paint cures so that when the cured coating is heated to diffuse the aluminum particulate material into the substrate, no bubbling or cracking of the coating occurs. Although other carriers have been tried, the M66-79 high heat aluminum paint is the preferred carrier.
The previous example illustrates the use of aluminum silicon alloy powders as a basic constituent of the slurry coating. It may be at times advantageous to employ pure aluminum powders or aluminum alloy powders containing other elements known to improve the oxidation resistant behavior of high temperature coatings such as chromium, yttrium, hafnium, rhenium, platinum or palladium, etc.
Similarly, additions of powders of these elements can be made directly to the slurry mixture.
Although other alternatives will be apparent to those skilled in the art, the applicants prefer to limit the scope of this invention to the ambit of the following claims. | A process of coating a refractory turbine part with a protective coating which is ultimately diffusion bonded to the part. A slurry coating material is prepared from a mixture of a silicon alkyd paint and suspended particles of an aluminum or aluminum alloy powder. Parts may be dipped in the slurry and subsequently be heat treated in selected atmospheres and temperatures to diffuse the coating into the surface of the part. | 2 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This is a divisional application of application Ser. No. 11/747,920, filed May 14, 2007.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a driving method for reducing image sticking effect of display images, and more specifically, to a driving method for reducing image sticking effect of images on a liquid crystal display (LCD).
[0004] 2. Description of the Prior Art
[0005] FIG. 1 is a diagram illustrating a cross-sectional view of a conventional liquid crystal display (LCD) 100 . As shown in FIG. 1 , the LCD 100 comprises two glass substrates, G 1 and G 2 , and a liquid crystal (LC) layer L 1 disposed between the glass substrates G 1 and G 2 . A plurality of data lines (not shown) and a plurality of scan lines (not shown) are laid on the glass substrate G 1 and are interwoven each other to form a plurality of the pixel areas. The liquid crystal layer L 1 comprises liquid crystal molecules X, of which the rotation can be controlled by applying voltage. In ideal condition, the LC layer L 1 only contains liquid crystal molecules X only. However, some other particles, namely impurities P, also exist in the liquid crystal layer L 1 . The impurities P, as shown in FIG. 1 , can be ions with positive or negative charges, or neutral molecules with certain polarities.
[0006] FIG. 2 is a diagram illustrating the general driving method of the conventional LCD 100 to display an image. As mentioned above, the pixel areas are formed by interweaving data lined and scan lines and therefore, the pixel areas are indexed as P mn where m and n indicate the number of the data line and scan line which are responsible for driving the pixel P mn . The data voltages carried by the data lines correspond to the displayed image. However, only when the scan line S n turns on, the data voltages on the data line D m is input into the pixel area P mn . For example, the data voltage on the fourth data line D 4 will be input into pixel area P 43 when the third scan line S 3 turns on, and so forth. Therefore, the LC molecules in the pixel P 43 will rotate according to the data voltages on the fourth data line D 4 when the third scan line S 3 turns on. Furthermore, when the scan line turns off, the data voltages on the data lines are not input into the pixels, and the liquid crystal molecules X in this pixel remain the state caused by the previous data voltages on the data lines. There are always data voltages on the data lines but the scan lines will sequentially turn on from G 1 to G n . As a result, an image is fully displayed on the screen while all data voltages on data lines are input into the pixels. The duration which this sequential process takes to display an image is called a “frame time”. Subsequently, the next frame starts while turning on the first scan line S 1 to the last scan line S n to show the next image, and so forth. In general, between two frames, there is a moment when all of the scan line turns off, which is so-called “blanking time”.
[0007] FIG. 3 is a diagram illustrating the relation between the rotation of the liquid crystal molecules X and the data voltages V d on the data lines in more detail. In reality, one end of the pixel areas is connected to the data line where a data voltage V d is applied, and the other end of the pixel is connected to the other glass substrate G 2 where a fixed common voltage V com is applied. Therefore, the actual voltage sensed by the liquid crystal molecules X in the pixel is the relative voltage difference between the data voltage V d and the common voltage V com . This relative voltage difference is the real factor that determines the rotation of the liquid crystal molecules X.
[0008] FIG. 4 is a diagram illustrating the distribution of the impurities P after the conventional LCD 100 displays an image for a period of time. If the data voltages V d on the data lines were perfectly symmetric AC (alternative current) waveform relative to the common voltage V com , the net movement of the impurities P would be zero and their distribution would remain as the initial condition. Nevertheless, the data voltages are slightly asymmetric AC waveforms unavoidably so that a net DC voltage is formed after displaying an image for a period of time. This DC voltage induces the positive-polarized impurities P moving and gradually accumulating at one side of the LC layer L 1 while the negative-polarized impurities P accumulate at the other side of the LC layer L 1 . These accumulated impurities P generate an inner electric field E in the liquid crystal layer L 1 , which shields off the following data voltage to apply on the liquid crystal molecules X. Consequently, the liquid crystal molecules X cannot rotate to the correct direction and the image sticking problem occurs.
[0009] FIG. 5 is a diagram illustrating the distribution of impurities P after the conventional LCD 100 displays images for a period of time. Besides the net DC voltage, the movement of the impurities P are affected by the directions of the liquid crystal molecules X as well. As shown in FIG. 5 , the liquid crystal molecules X points at a specific direction which is determined by the voltage difference V between data voltage V d and common voltage V com . Such a direction causes the horizontal movements of the impurities P other than the vertical movements. The impurities P therefore accumulate to form a “boundary” in the LC layer L 1 if the movements described above remain for a period of time. The impurities-formed boundaries in the LC layer L 1 distort the input voltage so that an abnormal image appears near the boundary which is the so-called line-shape image sticking.
SUMMARY OF THE INVENTION
[0010] The present invention provides a driving method for reducing image sticking associated with images of a liquid crystal display. The liquid crystal display comprises a plurality of data lines, a plurality of scan lines and a plurality of pixel areas. The driving method comprises turning on the plurality of data lines at a first period of time, sequentially turning on the plurality of the scan lines at the first period of time, inputting data of a first image to the plurality of the pixel areas to display at the first period of time, turning on the plurality of data lines at a second period of time, sequentially turning on the plurality of the scan lines at the second period of time, inputting data of a second image to the plurality of the pixel areas to display at the second period of time, turning off the plurality of scan lines between the first period of time and the second period of time, and applying a first voltage to a first set of the plurality of the data lines between the first period of time and the second period of time.
[0011] The present invention further provides a driving method for reducing image sticking associated with images of a liquid crystal display. The liquid crystal display comprises a plurality of data lines and a plurality of scan lines, a plurality of pixel areas. One end of each of the plurality of the pixel areas is connected to a common voltage. The driving method comprises converting a first data to a first voltage and a second voltage according to a first data-to-voltage relation, converting a second data to a third voltage and a fourth voltage according to a second data-to-voltage relation, turning on a first scan line of the plurality of scan lines in a first half of a period of time, applying the first voltage to a first corresponding pixel area of the plurality of pixel areas in a first half of a period of time, turning on the first scan line of the plurality of scan lines in a second half of the period of time, applying the second voltage to the first corresponding pixel area of the plurality of pixel areas in the second half of the period of time, turning on a second scan line of the plurality of scan lines in the first half of the period of time, applying the third voltage to a second corresponding pixel area of the plurality of pixel areas in the first half of the period of time, turning on a second scan line of the plurality of scan lines in the second half of the period of time, and applying the fourth voltage to the second corresponding pixel area of the plurality of pixel areas in the second half of the period of time. Wherein the sum of the difference between the first voltage and the common voltage and the difference between the second voltage and the common voltage is different from the sum of the difference between the third voltage and the common voltage and the difference between the fourth voltage and the common voltage.
[0012] The present invention further provides a driving method for reducing image sticking associated with images of a liquid crystal display. The liquid crystal display comprises a plurality of data lines, a plurality of scan lines, and a plurality of pixel areas. The driving method comprises converting a first data to a first voltage and a second voltage according to a data-to-voltage relation, converting a second data to a third voltage and a fourth voltage according to the data-to-voltage relation, turning on a first scan line of the plurality of scan lines in a first half of a period of time, applying a first voltage to a first pixel area of the plurality of pixel areas through a first data line in the first half of the period of time, turning on the first scan line of the plurality of scan lines in a second half of a period of time, applying a second voltage to the first pixel area of the plurality of pixel areas through the first data line in the second half of the period of time, turning on a second scan line of the plurality of scan lines in the first half of the period of time, applying the third voltage to a second pixel area of the plurality of pixel areas through a second data line in the first half of the period of time, turning on a second scan line of the plurality of scan lines in the second half of the period of time, and applying the fourth voltage to the second pixel area of the plurality of pixel areas through the second data line in the second half of the period of time. Wherein the first pixel areas and the second pixel areas are respectively coupled to a first common voltage and a second common voltage, and the sum of the difference between the third voltage and the second common voltage and the difference between the fourth voltage and the second common voltage is different from the sum of the difference between the first voltage and the first common voltage and the difference between the second voltage and the first common voltage.
[0013] These and other objectives of the present invention will no doubt become obvious to those of ordinary skill in the art after reading the following detailed description of the preferred embodiment that is illustrated in the various figures and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a diagram illustrating a cross-sectional view of a conventional LCD.
[0015] FIG. 2 is a diagram illustrating the general driving method of the conventional LCD.
[0016] FIG. 3 is a diagram illustrating the data voltage is applied on a pixel.
[0017] FIG. 4 is a diagram illustrating the distribution of the impurities P after the conventional LCD displays images for a period of time.
[0018] FIG. 5 is a diagram illustrating the distribution of the impurities P affected by the directions of liquid crystal molecules X after the conventional LCD displays images for a period of time.
[0019] FIG. 6 and FIG. 7 are diagrams illustrating the method for displaying images on a LCD with improved image sticking effect.
[0020] FIG. 8 is a diagram illustrating the LCD displaying images.
[0021] FIG. 9 is a diagram illustrating the method of the present invention applying voltages on the data lines during the blanking area B.
[0022] FIG. 10 is a diagram illustrating the voltages carried on the data lines D of the conventional LCD.
[0023] FIG. 11 and FIG. 12 are diagrams illustrating the present invention utilizing different data-to-voltage relations.
[0024] FIG. 13 is a diagram illustrating the voltage difference between the data lines D trapping the impurity particles P.
[0025] FIG. 14 and FIG. 15 are diagrams illustrating the present invention utilizing different common voltages.
DETAILED DESCRIPTION
[0026] FIGS. 6 and 7 are diagrams illustrating the driving method to improve image sticking for a LCD to display images. As shown in FIG. 6 , because a net DC electric field, which is induced by the imperfectly symmetric data voltages V d , and the specific direction of the liquid crystal molecules X, which is determined by the voltage difference between the data voltage V d and the common voltage V com , the impurities P move three-dimensionally to cross several data lines D in the liquid crystal layer L 1 . Finally the positive-polarized impurities P accumulate in a local region in the LC layer L 1 , and the negative-polarized impurities P accumulate in another local region in the LC layer L 1 . Please refer to FIG. 7 , the present invention applies high voltages on the data lines D to avoid the impurity particles P pass through the data lines D as shown in FIG. 6 . The high voltages applied on the data lines D trap the impurities P to prevent the impurities P from crossing several data lines D. In this way, each data line D will trap some impurities P but the amount of impurities P is inadequate to induce visible image sticking effect. Consequently, the degree of the accumulated impurities P in a local area of the LCD is eased and the image sticking problem is resolved.
[0027] According to FIG. 6 and FIG. 7 , the method of the present invention of trapping the impurity particles P by the data lines is disclosed. In FIG. 7 , positive voltages are applied on some of the data lines D in order to trap the negative-polarized impurities P, and negative voltages are applied on some of the data lines D in order to trap the positive-polarized impurities P. The values of the voltages applied on the data lines D shall be set to effectively trap the impurities P.
[0028] FIG. 8 is a diagram illustrating the conventional driving method for a LCD to display images. And the voltage in FIG. 8 represents the data voltage V d on the data lines D. As mentioned before, as an image is displayed, namely a frame time is completed, there is a moment called “blanking time” before the LCD to display the next image, namely to start the next frame. And all of the plurality of the scan lines turns off during the “blanking time” B. During the frame time, the data lines carry different AC (alternative current) voltage signals that correspond to the data of the displayed images. During the blanking time, the data lines carry a DC (direct current) voltage identical to the common voltage V com which is applied on the glass substrate G 2 . Therefore, the electrical potential in the liquid crystal layer L 1 is identical so that the impurities P are not trapped by the data lines under the conventional driving method for liquid crystal displays.
[0029] Nevertheless, since all of the plurality of the scan lines do not transmit any scan signals during the blanking time, any voltage signals carried by the data lines do not input into the pixels and do not affect the rotation of the liquid crystal molecules X either. Utilizing this characteristic of the blanking time B, the present invention applies high voltages on the data lines during the blanking time B to trap the impurities P.
[0030] FIG. 9 is a diagram illustrating the driving method to improve image sticking for a LCD, which applies high voltages on the data lines during the blanking time B. As shown in FIG. 9 , voltages which are higher than the common voltage Vcom are applied on the data lines D in order to trap the impurities P. However, applying voltages lower than the common voltage Vcom on the data lines D is also feasible to trap the impurities P.
[0031] FIG. 10 is a diagram illustrating the voltages carried on the data lines D of the conventional LCD. Generally, due to the characteristic of the liquid crystal molecules X, the data voltage signals on data lines D are AC (alternative current) signals, meaning the polarity of the data voltages are continuously alternated to prevent the liquid crystal molecules X from damage. It is assumed that a bit of data need a period T to transmit so that in the first half of the period T, the voltage on the data line D is positive with respect to the common voltage V com , and in the second half of the period T, the voltage on the data line D is negative with respect to the common voltage V com . The value of the voltages in the first half and the second half of the period T correspond to the content of the bit of the data. As shown in FIG. 10 , the common voltage Vcom is assumed to be 0 volts, the content of the data F 0 is 0 and the corresponding voltages in the first half and second half of the period T respectively are 0 and 0 volts, the content of the data F 1 is 1 and the corresponding voltages in the first half and the second half of the period T respectively are +1 and −1 volts, the content of the data F 2 is 2 and the corresponding voltages in the first half and the second half of the period T respectively are +2 and −2 volts, and so on. The voltages corresponding to the data F 0 , F 1 , F 2 received by the liquid crystal layer L 1 , in fact, are 0 and 0 volts, +1 and −1 volts, and +2 and −2 volts, because the common voltage Vcom is 0 volts.
[0032] FIG. 11 and FIG. 12 are diagrams illustrating the present invention utilizing different data-to-voltage relations to improve the image sticking. The data-to-voltage relation in FIG. 11 shifts +1 volt compared to the data-to-voltage relation in FIG. 10 . As shown in FIG. 11 , the content of the data F 0 is 0, and the corresponding voltages is 1 volt and 1 volt accordingly. The content of the data F 1 is 1, and the corresponding voltages are 2 volt and 0 volts. The content of the data F 2 is 2, and the corresponding voltages are 3 volt and −1 volt, and so on. The actual voltages received by the liquid crystal layer L 1 , since the common voltage V com is 0 volts, are 1 volt and 1 volt (corresponding to the data F 0 ), 2 volt and 0 volts (corresponding to the data F 1 ), 3 volt and −1 volt (corresponding to the data F 2 ), and so on. The data-to-voltage relation in FIG. 12 shifts −1 volt compared to the data-to-voltage relation in FIG. 10 . As shown in FIG. 12 , the content of the data F 0 is 0, and the corresponding voltages is −1 volt and −1 volt. The content of the data F 1 is 1, and the corresponding voltages are 0 volts and −2 volt. The content of the data F 2 is 2, and the corresponding voltages are 1 volt and −3 volt, and so on. The actual voltages received by the liquid crystal layer L 1 , since the common voltage V com is 0 volts, are −1 volt and −1 volt (corresponding to the data F 0 ), 0 volts and −2 volt (corresponding to the data F 1 ), 1 volt and −3 volt (corresponding to the data F 2 ), and so on. In the conventional LCD, all the data lines are applied with the same data-to-voltage relation for transmitting voltages to the liquid crystal layer so that on average, there is no voltage difference between data lines. In conventional driving method, therefore, it is easy for the impurities P to pass through the data lines in the liquid crystal layer L 1 . The present invention of driving method applies different data-to-voltage relations on the data lines as shown in FIG. 11 and FIG. 12 so that on average, there are voltage differences between data lines in the LCD of the present invention. For example, the first data-to-voltage relation is applied to the first data line D 1 and the second data-to-voltage relation is applied to the second data line D 2 . The first data-to-voltage relation is different from the second data-to-voltage relation and the first data line D 1 is adjacent to the second data line D 2 . As a result, on average, a voltage difference rises between the first data line D 1 and the second data line D 2 , and the voltage difference is set to be capable of trapping the impurities P. To, analogize, if there is always certain voltage difference between the data lines of the LCD, the movement of the impurities P is restricted, which lowers the degree of the accumulation of the impurities P in a local region of the LCD and reduces the image sticking accordingly.
[0033] FIG. 13 is a diagram illustrating the voltage difference between the data lines D trapping the impurity particles P. As shown in FIG. 13 , the voltage difference introduced by the different data-to-voltage relations applying on the adjacent data lines effectively traps the impurity particles P, restricts the movement of the impurities P and lowers the degree of the accumulation of the impurities P in a local region of the LCD.
[0034] FIG. 14 and FIG. 15 are diagrams illustrating the present invention utilizing different common voltages to improve the image sticking effect. The common voltage Vcom1 in FIG. 14 is shifted by +1 volt compared to the common voltage V com in FIG. 10 . As shown in FIG. 14 , the content of the data F 0 is 0, and the corresponding voltages is 0 volts and 0 volts. The content of the data F 1 is 1, and the corresponding voltages are +1 volt and −1 volt. The content of the data F 2 is 2, and the corresponding voltages are +2 volt and −2 volt, and so on. However, since the common voltage Vcom1 is +1 volt, the actual voltages received by the liquid crystal layer L 1 are −1 volt and −1 volt (corresponding to the data F 0 ), 0 volts and −2 volt (corresponding to the data F 1 ), +1 volt and −3 volt (corresponding to the data F 2 ), and so on. The common voltage V com2 in FIG. 15 is shifted by −1 volt compared to the common voltage in FIG. 10 . As shown in FIG. 15 , the content of the data F 0 is 0 and the corresponding voltages is 0 volts and 0 volts. The content of the data F 1 is 1 and the corresponding voltages are +1 volt and −1 volt. The content of the data F 2 is 2 and the corresponding voltages are +2 volt and −2 volt, and so on. However, since the common voltage V com2 is −1 volt, the actual voltages received by the liquid crystal layer L 1 are +1 volt and +1 volt (corresponding to the data F 0 ), 2 volt and 0 volts (corresponding to the data F 1 ), +3 volt and −1 volt (corresponding to the data F 2 ), and so on. In the conventional driving method of a LCD, all the data is converted to the voltage on the data lines according to the same data-to-voltage relation, and one end of all the plurality of the pixels is connected to the same common voltage Vcom ; therefore, on average, there is no voltage difference between data lines. In this conventional driving method, it is easy for the impurities P to pass through the data lines in a LCD. The present invention of driving method introduces different common voltages V com1 and V com2 , which means some of the pixels are connected to Vcom1 while the others are connected to V com2 as shown in FIG. 14 and FIG. 15 ; as a result, on average, there are voltage differences between pixel areas in the LCD of the present invention. For example, the first common voltage Vcom1 is connected to one end of the pixel area P 11 and the second common voltage V com2 is connected to one end of another pixel area P 21 . The first common voltage Vcom1 is different from the second common voltage V com2 and the pixel area P 11 is adjacent to the pixel area P 21 . In this driving method, on average, a voltage difference rises between the first pixel area and the second pixel area. And the voltage difference is capable of trapping the impurity particles P. To analogize, if there is always a certain voltage difference between pixel areas by connecting to different common voltages, the movement of the impurities P is restricted, which lowers the degree the accumulation of the impurities P in a local region of the LCD.
[0035] To sum up, the present invention utilizes: (1) applying voltages which are different from the common voltage during the blanking time, (2) converting data to voltage signals according to different data-to-voltage relations, and (3) connecting one end of the pixel areas to different common voltages, to effectively trap the impurities, restrict the movement of the impurities and lower the degree the accumulation of impurities; consequently, the image sticking effect is reduced and the display quality is ameliorated.
[0036] Those skilled in the art will readily observe that numerous modifications and alterations of the device and method may be made while retaining the teachings of the invention. Accordingly, the above disclosure should be construed as limited only by the metes and bounds of the appended claims. | A driving method with reducing image sticking effect is disclosed. The driving method includes applying a voltage on the data lines for trapping impurities crossing the data lines and lowering the degree of the image sticking effect, and applying different asymmetric waveforms to different data lines for trapping impurities crossing the data lines and lowering the degree of the image sticking effect. | 6 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to an apparatus for shaping a glass substrate, and more particularly, to an apparatus for shaping a glass substrate able to shape a glass substrate to have a three-dimensional (3D) shape while preventing the shape of a vacuum hole from being transferred to the surface of the glass substrate during vacuum shaping.
[0003] 2. Description of Related Art
[0004] Glass products are used in a variety of fields. For example, mobile phones use a cover glass to protect a touchscreen glass. Recently, products, the design of which can be varied using cover glasses having unique shapes according to final makers, are gaining increasing interest.
[0005] Cover glasses that have been used for mobile phones of the related art have a flat shape or curved corners. However, in response to the various functions and designs of mobile phones, curved glasses in which a pair of opposing edges from among the four edges is curved are currently being used for mobile phones.
[0006] A method of fabricating such a cover glass includes: preparing a mold having a shaping recess with a plurality of shaping holes formed on the bottom of the shaping recess; disposing the mold on a heated glass substrate; and applying vacuum, i.e. a force of drawing the glass substrate to the plurality of shaping holes, to the glass substrate through the plurality of shaping holes, thereby shaping the glass substrate to have the shape of the shaping recess. However, in this case, a high-pressure vacuum causes the shape of the vacuum holes to be transferred onto the surface of the shaped glass substrate, thereby leaving marks thereon.
RELATED ART DOCUMENT
[0007] Patent Document 1: Korean Patent No. 10-0701653 (Mar. 23, 2007)
BRIEF SUMMARY OF THE INVENTION
[0008] Various aspects of the present invention provide an apparatus for shaping a glass substrate able to shape at least one edge portion of the four edges of a glass substrate to have a curved surface while preventing the shape of a vacuum hole from being transferred to the surface of the glass substrate during vacuum shaping.
[0009] In an aspect of the present invention, provided is an apparatus for shaping a glass substrate that includes: a molding frame; a shaping recess disposed on one surface of the molding frame; at least one vacuum hole formed in the molding frame below the shaping recess, the at least one vacuum hole being connected to an external vacuum device; and at least one decompression recess defined between the shaping recess and the at least one vacuum hole such that the shaping recess communicates with the at least one vacuum hole. The decompression recess lessens vacuum pressure applied to the glass substrate disposed on the shaping recess through the at least one vacuum hole.
[0010] According to an embodiment of the present invention, the width of the decompression recess may be greater than the width of the at least one vacuum hole.
[0011] The apparatus may include a plurality of the vacuum holes and a plurality of the decompression recesses. Each decompression recess may correspond to each of the plurality of the vacuum holes.
[0012] The apparatus may include a plurality of the vacuum holes. At least two vacuum holes of the plurality of the vacuum holes may be connected to one decompression recess of the at least decompression recess.
[0013] Here, the at least two vacuum holes may be arranged in a row or column, and the apparatus may include a plurality of the decompression recesses, each of which extends along and is connected to the at least two vacuum holes in the row or column.
[0014] In addition, each of the plurality of the decompression recesses may have a trench structure in which the at least two vacuum holes arranged in a row or column is exposed.
[0015] At least one wall surface of the shaping recess may be a curved surface such that at least one edge portion of four edges of the glass substrate is shaped to have a curved surface.
[0016] The vacuum hole may have a first path having one end adjoining to the decompression recess and a second path connected to the other end of the first path. The inner diameter of the second path may be greater than the inner diameter of the first path.
[0017] According to the present invention as set forth above, the decompression hole for reducing a vacuum pressure applied to a glass substrate through the vacuum holes is formed at one side of the vacuum holes that face the glass substrate. With this configuration, a uniform pressure can be applied to one area of the glass substrate that faces the vacuum holes and the other area of the glass substrate, thereby preventing the shape of the vacuum holes from being transferred to the surface of the glass substrate that would otherwise leave marks on the surface of the glass substrate.
[0018] In addition, at least one wall surface of the shaping recess is formed as a curved surface, with which at least one edge portion of the four edges of the glass substrate can be shaped to have a curved surface, i.e. the glass substrate can be shaped to have a three-dimensional (3D) shape.
[0019] Furthermore, the diameter of one portion of each vacuum hole connected to the vacuum device is formed greater than the diameter of the opposite portion of each vacuum hole. This can consequently maximize the vacuum pressure applied to the glass substrate and ensure reproducibility in the shaping of the glass substrate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] FIG. 1 is a partial perspective view illustrating an apparatus for shaping a glass substrate according to a first exemplary embodiment of the present invention;
[0021] FIG. 2 is a cross-sectional view taken along line A-A in FIG. 1 ;
[0022] FIG. 3 is a partial perspective view illustrating an apparatus for shaping a glass substrate according to a second exemplary embodiment of the present invention;
[0023] FIG. 4 is a cross-sectional view taken along line B-B in FIG. 3 ;
[0024] FIG. 5 is a cross-sectional view taken along line C-C in FIG. 3 ;
[0025] FIG. 6 is a partial perspective view illustrating an apparatus for shaping a glass substrate according to a third exemplary embodiment of the present invention; and
[0026] FIG. 7 is an enlarged cross-sectional view of an area “D” in FIG. 7 .
DETAILED DESCRIPTION OF THE INVENTION
[0027] Reference will now be made in detail to an apparatus for shaping a glass substrate according to the present invention, embodiments of which are illustrated in the accompanying drawings and described below, so that a person skilled in the art to which the present invention relates could easily put the present invention into practice.
[0028] Throughout this document, reference should be made to the drawings, in which the same reference numerals and signs are used throughout the different drawings to designate the same or similar components. In the following description of the present invention, detailed descriptions of known functions and components incorporated herein will be omitted in the case that the subject matter of the present invention is rendered unclear.
[0029] Reference will now be made to an apparatus for shaping a glass substrate according to a first exemplary embodiment of the present invention in conjunction with FIG. 1 and FIG. 2 .
[0030] FIG. 1 is a partial perspective view illustrating the apparatus for shaping a glass substrate 100 according to the first embodiment, and FIG. 2 is a cross-sectional view taken along line A-A in FIG. 1 .
[0031] As illustrated in FIG. 1 and FIG. 2 , the apparatus for shaping a glass substrate 100 according the first embodiment is a shaping mold that can shape a glass substrate to have a three-dimensional (3D) shape, i.e. shape at least one edge portion of the four edges of the glass substrate to have a curved surface, using a vacuum. Herein, the shaping process using vacuum, i.e. the vacuum shaping, is a method of shaping a glass substrate (not shown) by heating the glass substrate (not shown) to a preset temperature, bringing the heated glass substrate (not shown) into contact with the shaping mold, and pressing the glass substrate (not shown) against the shaping mold using vacuum pressure. That is, the apparatus for shaping a glass substrate 100 according this embodiment is a shaping mold that shapes the glass substrate (not shown) having the shape of a two-dimensional (2D) flat glass to a 3D curved glass by vacuum shaping.
[0032] For this, the apparatus for shaping a glass substrate 100 according this embodiment includes a molding frame 110 , a shaping recess 120 , vacuum holes 130 and decompression recesses 140 .
[0033] The molding frame 110 forms the outer shape of the apparatus for shaping a glass substrate 100 . For example, the molding frame 110 may have an overall box-shaped structure. The molding frame 110 may be made of a material having superior resistance to abrasion, impacts and heat, such as carbon steel, alloy steel or stainless steel.
[0034] The molding recess 120 is formed inward from one surface of the molding frame 110 , more particularly, one surface of the molding frame 110 that is to face the glass substrate (not shown). Here, since the apparatus for shaping a glass substrate 100 according this embodiment is an apparatus that shapes the glass substrate (not shown) such that the glass substrate (not shown) has a 3D shape, i.e. at least one edge portion of the four edges of the glass substrate (not shown) has a curved surface, at least one wall surface of the shaping recess 120 that determines the shape of the glass substrate (not shown) is formed as a curved surface. In addition, the width of the shaping recess 120 is smaller than that of the glass substrate (not shown) in order to impart the curved surface to the glass substrate (not shown).
[0035] The vacuum holes 130 provide paths through which vacuum pressure generated from an external vacuum device (not shown) is transferred to the glass substrate (not shown) aligned on the shaping recess 120 . When the glass substrate (not shown) is being shaped, vacuum, i.e. a force of drawing the glass substrate (not shown) toward the shaping recess 120 , is applied to the glass substrate (not shown) through the vacuum holes 130 , thereby shaping the glass substrate (not shown) to have the shape of the shaping recess 120 . The vacuum holes 130 are formed in the molding frame 110 below the shaping recess 120 . The vacuum holes 130 may be in the shape of cylinders. In addition, as illustrated in FIG. 1 and FIG. 2 , a plurality of vacuum holes 130 may be provided. The plurality of vacuum holes 130 may be arranged as being aligned in columns and rows in order to cause vacuum pressure to be uniformly applied over the entire surface of the glass substrate (not shown). The plurality of vacuum holes 130 is connected to a vacuum device (not shown) such as a vacuum pump that is disposed outside. For the sake of efficiency, the plurality of vacuum holes 130 may be connected, at one end thereof, to a common path (not shown) through which the plurality of vacuum holes 130 communicates with each other, and the vacuum device (not shown) may be connected to the common path (not shown) in a one-to-one relationship. That is, the plurality of vacuum holes 130 may be connected to the vacuum device (not shown) via the common path (not shown), and vacuum pressure applied from the vacuum device (not shown) may be connected uniformly distributed before being applied to the glass substrate (not shown) via each of the plurality of vacuum holes 130 .
[0036] The decompression recesses 140 are defined between the shaping recess 120 and the vacuum holes 130 such that the vacuum holes 130 communicate with the shaping recess 120 , thereby allowing vacuum pressure applied through the vacuum holes 130 to be transferred to the shaping recess 120 . The decompression recesses 140 are configured to lessen vacuum pressure applied to the glass substrate (not shown) disposed or aligned on the vacuum recess 120 through the vacuum holes 130 . For this, the width of each of the decompression recesses 140 may be greater than the width of each of the vacuum holes 130 . As illustrated in FIG. 1 and FIG. 2 , the decompression recesses 140 may be in the shape of cylinders like the vacuum holes 130 . In addition, the decompression recesses 140 may correspond to the vacuum holes 130 in a one-to-one relationship. When viewed on a plane, one vacuum hole 130 defining a circle is located inside a greater circle defined by one decompression recess 140 . Accordingly, when vacuum pressure is transferred to the glass substrate (not shown) through the narrow vacuum holes 130 , it is lowered through the wider decompression holes 140 before being applied to the glass substrate (not shown).
[0037] As in the related art, when the vacuum holes are in direct contact with the glass substrate (not shown), the shape of the vacuum holes may be transferred to the surface of the glass substrate (not shown) due to high pressure, thereby leaving marks on the surface of the glass substrate (not shown). However, as described above, when the vacuum pressure applied to the glass substrate (not shown) through the vacuum holes 130 is lessened by the decompression recesses 140 , it is possible to reduce the difference between the pressure applied to one area of the glass substrate (not shown) that faces the vacuum holes 130 and the pressure applied to the other area of the glass substrate (not shown) or make uniform pressure be applied to both areas of the glass substrate, thereby preventing the shape of the vacuum holes 130 from being transferred to the surface of the glass substrate (not shown) that would otherwise leave marks on the surface of the glass substrate (not shown).
[0038] Reference will now be made to an apparatus for shaping a glass substrate according to a second exemplary embodiment of the present invention in conjunction with FIG. 3 to FIG. 5 .
[0039] FIG. 3 is a partial perspective view illustrating the apparatus for shaping a glass substrate 200 according to the second embodiment, FIG. 4 is a cross-sectional view taken along line B-B in FIG. 3 , and FIG. 5 is a cross-sectional view taken along line C-C in FIG. 3 .
[0040] As illustrated in FIG. 3 to FIG. 5 , the apparatus for shaping a glass substrate 200 according to the second embodiment includes a molding frame 110 , a shaping recess 120 , vacuum holes 130 and decompression recesses 240 .
[0041] Since the second embodiment is substantially identical to the first embodiment except for the structure of the decompression recesses, like reference numerals will be used to designate the same or like elements, descriptions of which are omitted.
[0042] As illustrated in FIG. 3 to FIG. 5 , according to the second embodiment, a plurality of vacuum holes 130 and a plurality of decompression recesses 240 are provided. Here, at least two vacuum holes 130 are connected to each decompression recess 240 . Specifically, according to this embodiment, each decompression recess 240 extends along a row or column of the plurality of vacuum holes 130 , and a group of vacuum holes 130 of the plurality of vacuum holes 130 arranged in a row or column is connected to each decompression recess 240 and is exposed toward the shaping recess 120 . For example, each decompression recess 240 has a trench structure, with which the corresponding group of vacuum holes 130 is exposed toward the shaping recess 120 . In this case, like the decompression recesses ( 140 in FIG. 2 ) according to the first embodiment of the present invention, the width of each decompression recess 240 is greater than the width of each vacuum hole 130 . Since this structure expands the space, a high-vacuum pressure passing through the plurality of vacuum holes 130 can be lessened, thereby preventing the shape of the vacuum holes 130 from being transferred to the surface of the glass substrate (not shown) that would otherwise leave marks the glass surface.
[0043] Reference will now be made to an apparatus for shaping a glass substrate according to a third exemplary embodiment of the present invention in conjunction with FIG. 6 and FIG. 7 .
[0044] FIG. 6 is a partial perspective view illustrating the apparatus for shaping a glass substrate 300 according to the third embodiment, and FIG. 7 is an enlarged cross-sectional view of an area “D” in FIG. 7 .
[0045] As illustrated in FIG. 6 and FIG. 7 , the apparatus for shaping a glass substrate 300 according to the third embodiment includes a molding frame 110 , a shaping recess 120 , vacuum holes 330 and decompression recesses 140 .
[0046] Since this embodiment is substantially identical to the first embodiment except for the structure of the vacuum holes, like reference numerals will be used to designate the same or like elements, descriptions of which are omitted.
[0047] Each of the vacuum holes 330 according to this embodiment has a two-section structure that includes two sections having different diameters. As illustrated in FIG. 6 and FIG. 7 , each vacuum hole 330 includes a first path 331 having one end adjoining to a corresponding decompression recess 140 and a second path 332 connected to the other end of the first path 331 . The inner diameter of the second path 332 may be greater than the inner diameter of the first path 331 . With this configuration, a vacuum pressure, i.e. a drawing force, applied from a vacuum device (not shown) can be enhanced when it is transferred from the greater space of the second path 332 to the smaller space of the first path 331 , thereby maximizing the vacuum pressure applied to a glass substrate (not shown). This can consequently ensure reproducibility in the shaping of the glass substrate (not shown).
[0048] The foregoing descriptions of specific exemplary embodiments of the present invention have been presented with respect to the drawings. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible for a person having ordinary skill in the art in light of the above teachings.
[0049] It is intended therefore that the scope of the present invention not be limited to the foregoing embodiments, but be defined by the Claims appended hereto and their equivalents. | The present invention relates to an apparatus for molding a glass substrate, and more specifically, to an apparatus for molding a glass substrate capable of forming a glass substrate in a 3D shape and preventing the shape of a vacuum hole from transferring onto the surface of the substrate. To this end, the present invention provides the apparatus for molding a glass substrate comprising: a molding frame; a molding groove formed on one surface of the molding frame; at least one vacuum hole formed on the molding frame at the lower portion of the molding groove and is connected to an external vacuum device; and a pressure-reducing groove, which is formed between the molding groove and the vacuum hole and allows communication between the molding groove and the vacuum hole, for reducing vacuum pressure applied to the glass substrate positioned on the molding groove through the vacuum hole. | 2 |
FIELD OF THE INVENTION
The present invention relates to a method of manufacturing a fine-particle colloid or a magnetic fluid of a metal nitride. More particularly, the present invention relates to a novel manufacturing method which permits the manufacture of a fine-particle colloid or a magnetic fluid of a metal nitride having a uniform particle size and excellent dispersibility.
DESCRIPTION OF THE PRIOR ART
As a method of synthesizing fine particles or a magnetic fluid of iron nitride, the plasma CVD method has been conventionally known. This method comprises introducing iron carbonly, Fe(CO) 5 , vapor into glow discharge plasma, for example, of ammonia gas, NH 3 , producing fine particles of iron nitride through reaction between iron, Fe, atoms produced from dissociation of iron carbonyl, Fe(CO) 5 , in plasma and ammonia, NH 3 , molecules excited by plasma, and entrapping these fine particles into an oily medium containing a surfactant, thereby manufacturing a magnetic fluid. A plasma CVD device for rational and efficient progress of this reaction has already been developed.
However, although this method has a wide scope of application, the reaction proceeds in glow discharge plasma, which is an ionized low-pressure gas, and fine particles of iron nitride formed in the vapor phase continue to fusion-grow while repeating mutual collision during the period until the particles diffuse in the vapor phase and are deposited onto the inner wall of the reactor, and as a result, the size of the fine particles have a large statistical distribution, thereby making it difficult to obtain fine particles of a uniform size.
Another method for synthesizing fine particles or a magnetic fluid of a metal nitride is the vapor-liquid phase reaction method already established by the present inventors. This method comprises heating a non-aqueous solution of a metal carbonyl such as iron carbonyl, Fe(CO) 5 , and a surfactant while pouring ammonia gas, NH 3 , into the solution, thereby causing production of fine particles of the metal nitride such as iron nitride in the non-aqueous solution. According to this method, nuclear formation and growth of fine particles proceed in the solution, so that the size of fine particles is far more uniform than in the above-mentioned plasma CVD method.
However, even in the latter method, when using as the starting material a solution in which a metal carbonyl has been dissolved to a high concentration in an attempt to obtain a high-concentration colloid of fine particles of metal nitride or a fluid with highly saturated magnetization of a metal nitride, fine particles have an extremely large particle size and are non-uniform, and this causes serious impairment of the dispersion stability of the high-concentration colloid. In fact, this method was not suitable for the manufacture of a high-concentration fine-particle colliod. Therefore, when attempting to obtain a high-concentration fine-particle colloid or a fluid with high-saturation magnetization by this method, it is necessary to use a two-step process comprising once synthesizing a low-concentration colloid, and then concentrating the resultant colloid through evaporation of the solvent.
SUMMARY OF THE INVENTION
The present invention relates to method of manufacturing a fine-particle colloid or a magnetic fluid of a metal nitride which comprises introducing a nitrogen-bearing compound in a solvent containing a metal carbonyl and a surfactant, and heating the mixture to cause a reaction. According to this method, one can produce a fine-particle colloid or a magnetic fluid of a metal nitride having a reduced fine particle size and uniform distribution thereof, even when manufacturing a fine-particle colloid or a magnetic fluid with a high concentration of metal nitride.
Another object of the present invention is to provide a vapor-liquid phase reactor which permits efficient and simple manufacture of a fine-particle colloid or a magnetic fluid of a metal nitride without the need for a complicated process.
A further object of the present invention is to provide a method of manufacturing a magnetic fluid of a metal nitride, which permits configuration of a dispersion system in response to a particular purpose of use and application of the magnetic fluid.
These and other objects, features and benefits of the present invention will be more clearly understood by reading the following detailed description and drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a sectional view illustrating an embodiment of the apparatus applicable for the present invention;
FIG. 2 (a) and (b) are sectional views respectively illustrating a flow resistant element; and
FIG. 3 is a sectional view illustrating another embodiment of the apparatus applicable for the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The present invention has a construction based on the clarification of the following reaction mechanism.
In the vapor-liquid phase reaction, iron carbonyl reacts with ammonia, as shown in the following reaction formulae I and II, to form, as a precursor, and iron carbonyl amino complex, Fe(CO) 1 (NH m ) n , which is sequentially dissociated to produce fine particles of iron nitride:
Fe(CO).sub.5 +NH.sub.3 →Fe.sub.3 (CO).sub.9 (NH).sub.2 →Fe.sub.2 (CO).sub.6 (NH.sub.2).sub.2 +CO+H.sub.2 (I)
Fe.sub.2 (CO).sub.6 (NH.sub.2).sub.2 →Fe.sub.3 N+CO+NH.sub.3 +H.sub.2(II).
The reaction I which forms the precursor prevails at a reactor temperature of higher than 70° C., whereas the reaction II in which iron nitride is formed from the precursor occurs at a temperature of higher than 120° C.
In parallel with these reactions, those of direct dissociation without the reaction of Fe(CO) 5 with NH 3 tend to take place simultaneously, as shown in the following formulae III to V:
2Fe(CO).sub.5 →Fe.sub.2 (CO).sub.9 +CO III
3Fe.sub.2 (CO).sub.9 →2Fe.sub.3 (CO).sub.12 +3CO IV
Fe.sub.3 (CO).sub.12 →3Fe+12CO V.
These reactions III to V occurring at a temperature higher than 100° C. are well known, producing generally non-crystalline iron particles, a-Fe.
If Fe(CO) 5 is present upon heating to a temperature of at least 120° C., a-Fe, therefore, is always by-produced in addition to Fe 3 N which is the target of reaction, thus resulting in a decreased reaction yield of iron nitride. Since a-Fe present in mixture not only impairs chemical stability of the magnetic fluid as a whole, but also is precipitated onto the surfaces of Fe 3 N fine particles, Fe 3 N fine particles coagulate together with each other so that fine particles become coarser ones, thus causing the magnetic fluid to lose dispersion stability thereof.
The present inventors, therefore, carried out extensive studies, and found that the above-mentioned problem could be solved by working out the manufacturing method so as to inhibit the sub-reaction III and cause only the main reaction I to occur, thus completing the present invention.
More specifically, in the present invention, when using iron carbonyl, Fe(CO) 5 , for example, as the metal carbonyl, a two-step reaction process is carried out, which comprises synthesizing a precursor substance at a temperature lower than 100° C., and then synthesizing iron nitride from the precursor substance st a higher temperature higher than 120° C. Between these two reaction steps, an appropriate step for the elimination of unreacting Fe(CO) 5 , for example, may be inserted. This step may comprise, for example, distilling the reaction products under a reduced pressure after the completion of the synthesizing reaction of the precursor substance, or using a rational apparatus preventing the reaction products from participating in the subsequent reaction by bringing apart from the reactor in space. When a high-concentration colloid is to be made available, the above-mentioned process may be repeated multiple times.
In an apparatus applicable for the present invention, as shown in FIG. 1, for example, a lid (8) having several air-tight inlet flanges (5), (6) and (7) is hermetically connected to a round-bottomed reactor (4) made of a refractory, or more preferably, of a metal. A rotary shaft is inserted into the inlet flange (5), and a stirrer (9) is attached to the tip of the rotary shaft to permit stirring solution (10). A nitrogen-bearing compound such as NH 3 gas, for example, is introduced through an inlet pipe (11), and an inert gas such as Ar gas, for example, is introduced through another inlet pipe (12). In addition, a thermocouple or a resistance thermometer (13), for example, for measuring and controlling the reaction temperature is inserted into the reactor (4) through the flange (6). A metal carbonyl liquid (14) such as Fe(CO) 5 , for example, is introduced through the inlet flange (7), and a surfactant (16) is added to the reaction system through an inlet port (15). The structure should permit heating the bottom of the reactor (4) by a resistance heater (17).
In this embodiment, a flow resistant element (2) which is low in flow resistance relative to vapor and high in flow resistance relative to liquid is provided at the bottom of a cooler (1), and via this flow resistant element (2), the cooler (1) is connected to a gas discharge port (18) of the lid (8) of the reactor (4). A reservoir (3) is provided at the top of the cooler (1) to discharge waste gas through this reservoir (3) to outside the reaction system.
The flow resistant element (2) having appropriate construction and properties presents the following functions and effects.
During the synthesizing reaction of the precursor substance at a low temperature in the first step, for example, lower than 100° C., i.e., when iron carbonyl, Fe(CO) 5 , has a low vapor pressure, vapor in only a small amount flows up from the bottom through the flow resistant element (2). The liquid of iron carbonyl having been condensed in the cooler (1), therefore, flows down through the flow resistant element (2) into the reactor (4). During the subsequent reaction in the second step for synthesizing iron nitride from the precursor substance, on the other hand, at a higher temperature, for example, at 120° C., the raw material iron carbonyl has a high vapor pressure, so that vapor in a larger amount flows up through the flow resistant element (2). Consequently, the liquid of iron carbonyl having been condensed in the cooler (1) does not flow down, but is pushed up to stay in the reservoir (3), so that the concentration of iron carbonyl in the reactor is kept very low during the progress of the second-step reaction.
When causing the synthesizing reaction of the precursor again at a temperature lower than 100° C. to increase the colloid concentration, iron carbonyl stored in the reservoir (3) flows down again into the reactor (4). Thus, iron carbonyl participates in the reaction while moving reciprocally between the reactor and the liquid reservoir until the entire mass participates in the reaction.
As the flow resistant element (2) having such functions and effects, a structure having an orifice (19) inserted in the middle of the pipe as shown in FIG. 2(a) may be used, or one with multiple orifices as shown in FIG. 2(b) may also be employed. This may also be a hose having an appropriately small inside diameter and an appropriate length. The shape, design and size may be decided appropriately taking account of the flow rate of the flowing vapor, the vapor pressure of metal carbonyl, and viscosity thereof.
By using an apparatus as described above, operation of eliminating unreacting metal carbonyl becomes simpler and easier than in distillation under a reduced pressure, thus enabling to improve operational efficiency. The cooling step for cooling the reaction system, which is required for the distillation under a reduced pressure, is not necessary, thus permitting improvement of the energy efficiency. In addition, this apparatus allows to utilize all unreacting raw materials, and thus to improve the utilization efficiency of raw material.
With the method of manufacturing a magnetic fluid of iron nitride as an example, the reaction process is described below.
Ammonia gas NH 3 , or a mixed gas of ammonia gas, NH 3 , and an inert gas such as Ar is introduced into kerosene solution (10) containing dissolved iron carbonyl, Fe(CO) 5 , and a surfactant, and the mixture is heated to 100° C. while stirring with a stirrer (9). In this process, vapor of iron carbonyl and kerosene condenses at the cooler (1) and flows back to the reactor (4). CO and H 2 generated and NH 3 in excess pass through the cooler (1) and are discharged to outside the system. A precursor of an appropriate concentration is produced in the reactor (4). Then, by heating the reactor during inflow of NH 3 to a temperature of at least 120° C., excess Fe(CO) 5 having a high vapor pressure, which has not participated in the formation of the precursor, is condensed at the cooler (1) and stays in the reservoir (3), whereas the precursor of a low vapor pressure remains within the reactor (4) and is dissociated to form fine iron nitride particles. By repeating this process several times, the raw material Fe(CO) 5 is finally consumed while flowing forward and backward between the reactor (4) and the reservoir (3), reaction being completed.
The magnetic fluid of iron nitride with kerosene as a solvent is thus obtained.
According to this method, it is possible to achieve a uniform particle size of fine iron nitride particles in the dispersed phase and to adjust the particle size to any value within a range of from 6 to 12 nm at an accuracy of 1 nm, with a saturation magnetic flux density of from 400 to 1,000 gauss. Following the above-mentioned reaction, by concentrating the magnetic fluid resulting from the reaction through distillation of part of kerosene in the reactor, a magnetic fluid of iron nitride having a very high performance is available as typically represented by a saturated magnetic flux density of 2,400 Gauss on the maximum.
Kerosene presented as an example in the process as described above, being a solvent of the reaction solution at the start of reaction, becomes a solvent for the magnetic fluid with no change at the end of the reaction. While kerosene does not positively participate in the reaction, it is considered the most suitable for the above-mentioned reaction temperature and distillation temperature because the boiling-point of kerosene distributes at the range of 150° to 250° C.
The present invention allows, on the other hand, one to appropriately change the solvent for the magnetic fluid, depending upon the purpose of use and application.
The vacuum seal of the rotary shaft using the magnetic fluid is widely applied, for example, for a manufacturing apparatus of semiconducting materials, an X-ray generator, and other apparatuses under vacuum. Because the magnetic fluid is directly exposed to vacuum in these apparatuses, the solvent for the magnetic fluid must have a low vapor pressure and be hard to evaporate. Without a sufficiently low vapor pressure, solvent vapor would contaminate the vacuum apparatus, and the solvent for the magnetic fluid would be lost through evaporation. As a result, the magnetic fluid itself would lose fluidity thereof, transforming from sol to gel, and the vacuum seal would be broken. Alkylnaphthalene is widely used in general as a solvent for the magnetic fluid applied in such a vacuum seal.
The dust preventing seal of a rotary shaft using a magnetic fluid is employed in a rotary bearing for a computer hard disk, the mirror of a laser printer, a VCR magnetic head, or various rotating devices in a clean room. As the magnetic fluid works in these apparatuses under atmospheric pressure, it is not necessary for the vapor pressure thereof to be so low as the magnetic fluid for a rotary seal. However, the solvent for the magnetic fluid should have a particularly low viscosity coefficient so as to permit high-speed rotation with a small torque. In a magnetic fluid for such a dust preventing seal, the spindle oil of an olefin is widely applied as the solvent.
When the magnetic fluid is used for an inclination sensor or an acceleration meter, the fluidity and thermal stability must be satisfactory at respective temperatures at which these apparatuses work. When a magnetic fluid is used, on the other hand, as a mechanical part of an actuator or a damper, it should have a sufficient lubricity and should preferably be hardly flammable.
To cope with these diverse uses, the properties of the magnetic fluid should preferably be adjusted for each use.
In the present invention, therefore, after synthesizing a magnetic fluid of a metal nitride with a low-boiling-point liquid such as kerosene as the reaction solvent in the reactor (4), another solvent for replacement is added in the same reactor (4). This solvent should have a boiling point higher than that of the reaction solvent used for synthesis. A receptacle (20) is provided between the reactor (4) and the cooler (1), and ammonia gas or a mixed gas thereof with an inert gas is introduced under the same conditions as in the synthesis of the above-mentioned magnetic fluid carried out while heating the reactor (4) and stirring the contents therein, and is discharged through the cooler (1) to outside the system.
Through this process, the vapor of the reaction solvent having a low boiling-point is carried by the introduced gas, condensed at the cooler (1), and then stored in the receptacle (20). The added solvent having a high boiling-point stays, on the other hand, in the reactor (4), and thus the replacement is completed.
The solvent to be added for replacement may be an oil such as a fatty acid ester, a lubricant oil such as paraffin hydrocarbon oil, a naphthene hydrocarbon oil, an olefin hydrocarbon oil, or a monocyclic or polycyclic aromatic hydrocarbon oil, or a synthetic lubricant oil, such as dimethylsilicone, a pentaerythritol ester, a trimethylopropane ester, a polyolefin, a polybutene, a polyethylene glycol, polypropylene glycol, a tetradecilsilicate, tetraoctylsilicate, 2-ethylhexanol diester, an adipic ester, a sebacic acid ester, a polyphenyl ester, or a propylphenyl phosphate. These solvents should preferably have a vapor pressure lower by about a digit than that of the initial reaction solvent used for the synthesis of the magnetic fluid. By appropriately selecting a combination of two kinds of solvents, it is possible to accomplish a replacement for almost all the kinds solvents. Also, by appropriately adjusting the amount of addition, the concentration can be effected simultaneously with the replacement.
The above-mentioned method is a forced fractional distillation method based on the introduction of a carrier gas. The present invention is not, however, limited to this method. Introduction of the carrier gas is not necessarily required, and the extraction method, for example, is also effective for replacement.
According to the method of the present invention, the following effects are achievable:
1) a fine-particle colloid or a magnetic fluid having a satisfactory dispersibility and hard to aggregate is available;
2) a fine-particle colloid or a magnetic fluid having a low viscosity and high in fluidity is available;
3) a fine-particle colloid or a magnetic fluid having a high concentration is available;
4) a magnetic fluid having a high magnetization is available;
5) fine magnetic particles hard to be oxidized are available; and a magnetic fluid chemically stable even in a humid atmosphere is available;
6) an expensive device or facility is not required for the manufacture;
7) sophisticated knowledge or expertise is not required for the manufacture;
8) a lower-cost raw material is applicable;
9) fewer manufacturing steps are required with an improved operating efficiency;
10) the manufacturing process is simpler with a largely improved manufacturing efficiency;
11) the production quantity per unit time is larger;
12) no toxic substance is produced;
13) the vapor pressure of the magnetic fluid can be adjusted to any of various values;
14) the viscosity coefficient of the magnetic fluid can be adjusted to any of various values;
15) the other properties in respect to any of the magnetic fluids, including, for example, low-temperature fluidity, thermal stability, oxidation stability, hydrolysis stability, hard flammability, lubricity, and adaptability to living organisms, are freely adjustable.
Now, the present invention will be further described in detail by means of examples.
EXAMPLE 1
N-tetraethylenetetraaminopolybutenyl imido succinate in an amount of 23.6 g (molecular weight: approximately 1,300) was dissolved in kerosene in an amount of 50 g as a surfactant. Then, a reaction solution containing iron carbonyl, Fe(CO) 5 , in an amount of 170.5 g was introduced into a reactor made of refractory glass attached with a stirrer, and the mixture was first heated to 80° C. for one hour while introducing ammonia gas, NH 3 , at a rate of 390 cc per minute into the reaction solution to synthesize an iron amino carbonyl compound, which is a precursor substance. Subsequently, unreacting Fe(CO) 5 was distilled under a reduced pressure, and collected in another container, and the remaining reaction solution was heated to a temperature of 130° C. for one hour. Further, Fe(CO) 5 which has previously been collected is added again to the reaction solution, and this process was repeated four times in total, to complete all the reactions through a total consumption of 170.5 g of Fe(CO) 5 .
The obtained iron nitride colloid comprised fine particles having a satisfactory crystallinity of Fe 3 N and Fe 4 N phases, giving a yield of almost 100% as nitride. The fine particles had a uniform size, with an average particle size of 6.5 nm, approximately 90% of the fine particles being within a range of ±1 nm.
EXAMPLE 2
N-tetraethylenetetraaminopolybutenyl imido succinate in an amount of 11.3 g (molecular weight: approximately 1,300) was dissolved in kerosene in an amount of 50.1 g as a surfactant. Then, a reaction solution containing iron carbonyl, Fe(CO) 5 , in an amount of 150 g was introduced into a reactor made of refractory glass attached with a stirrer, and the mixture was first heated to 80° C. for one hour while introducing ammonia gas, NH 3 , at a rate of 800 cc per minute into the reaction solution to synthesize an iron amino carbonyl compound, which is a precursor substance.
Subsequently, the temperature of the reaction solution was increased to 185° C. and further heated for one hour under the same conditions as above. By repeating this process five times, the raw material, Fe(CO) 5 , was totally consumed to form fine iron nitride particles. The obtained iron nitride magnetic fluid was a kerosene-based magnetic fluid comprising kerosene in which fine iron nitride particles were dispersed, having a saturated magnetic flux density of 705 Gauss and a viscosity coefficient of 12.5 mPa.s. Alkylnaphthalene was added in an amount of 35 g to this kerosene-based metal nitride magnetic fluid, and a receptacle was provided at the reaction gas exit of the reactor, as shown in FIG. 3. Under the same conditions as in the reaction, kerosene vapor was forcedly transported through the receptacle to the cooler while introducing ammonia gas at a flow rate of 800 cc per minute into the reactor, and kerosene was collected in the receptacle through fractional distillation. Alkylnaphthalene-based iron nitride magnetic fluid was thus obtained in an amount of 65 cc, which had a saturated magnetic flux density of 900 Gauss, a viscosity coefficient of 200 mPa.s., and excellent dispersibility.
It is needless to say that the present invention is not limited to the above-mentioned cases of iron carbonyl, Fe(CO) 5 , and iron nitride, but is applicable to carbonyls and nitrides of nickel, cobalt, tungsten, molybdenum and any other metals, and the operating conditions such as temperature may be changed in accordance with the kind of metal selected. | A method of manufacturing a fine-particle colloid or a magnetic fluid of a metal nitride through reaction between a metal carbonyl and a nitride-bearing compound, a two-step reaction is performed, comprising a first-step reaction of synthesizing a nitrogen-bearing metal carbonyl which is a precursor substance and a second-step reaction of synthesizing metal nitride from said precursor substance. A step of eliminating unreacted metal carbonyl is provided between the two-step reaction. By repeatedly causing the series of reactions, a fine-particle colloid or a magnetic fluid of the metal nitride is manufactured. For the magnetic fluid, the solvent may be replaced in response to a particular purpose of use of application after production. | 2 |
FIELD OF INVENTION
This invention relates to a liquid dish cleaning composition which is designed to remove stains from surfaces and also disinfect surfaces like dishes, countertops, sponges, while maintaining good foaming grease cutting, rinsing and mildness properties.
BACKGROUND OF THE INVENTION
The present invention relates to novel light duty liquid detergent compositions with high foaming and good grease cutting properties as well as disinfecting properties.
The prior art is replete with light duty liquid detergent compositions containing nonionic surfactants in combination with anionic and/or betaine surfactants wherein the nonionic detergent is not the major active surfactant. In U.S. Pat. No. 3,658,985 an anionic based shampoo contains a minor amount of a fatty acid alkanolamide. U.S. Pat. No. 3,769,398 discloses a betaine-based shampoo containing minor amounts of nonionic surfactants. This patent states that the low foaming properties of nonionic detergents renders its use in shampoo compositions non-preferred. U.S. Pat. No. 4,329,335 also discloses a shampoo containing a betaine surfactant as the major ingredient and minor amounts of a nonionic surfactant and of a fatty acid mono- or di-ethanolamide. U.S. Pat. No. 4,259,204 discloses a shampoo comprising 0.8 to 20% by weight of an anionic phosphoric acid ester and one additional surfactant which may be either anionic, amphoteric, or nonionic. U.S. Pat. No. 4,329,334 discloses an anionic-amphoteric based shampoo containing a major amount of anionic surfactant and lesser amounts of a betaine and nonionic surfactants.
U.S. Pat. No. 3,935,129 discloses a liquid cleaning composition containing an alkali metal silicate, urea, glycerin, triethanolamine, an anionic detergent and a nonionic detergent. The silicate content determines the amount of anionic and/or nonionic detergent in the liquid cleaning composition. However, the foaming properties of these detergent compositions are not discussed therein.
U.S. Pat. No. 4,129,515 discloses a heavy duty liquid detergent for laundering fabrics comprising a mixture of substantially equal amounts of anionic and nonionic surfactants, alkanolamines and magnesium salts, and, optionally, zwitterionic surfactants as suds modifiers.
U.S. Pat. No. 4,224,195 discloses an aqueous detergent composition for laundering socks or stockings comprising a specific group of nonionic detergents, namely, an ethylene oxide of a secondary alcohol, a specific group of anionic detergents, namely, a sulfuric ester salt of an ethylene oxide adduct of a secondary alcohol, and an amphoteric surfactant which may be a betaine, wherein either the anionic or nonionic surfactant may be the major ingredient.
The prior art also discloses detergent compositions containing all nonionic surfactants as shown in U.S. Pat. Nos. 4,154,706 and 4,329,336 wherein the shampoo compositions contain a plurality of particular nonionic surfactants in order to affect desirable foaming and detersive properties despite the fact that nonionic surfactants are usually deficient in such properties.
U.S. Pat. No. 4,013,787 discloses a piperazine based polymer in conditioning and shampoo compositions which may contain all nonionic surfactant or all anionic surfactant.
U.S. Pat. No. 4,450,091 discloses high viscosity shampoo compositions containing a blend of an amphoteric betaine surfactant, a polyoxybutylenepolyoxyethylene nonionic detergent, an anionic surfactant, a fatty acid alkanolamide and a polyoxyalkylene glycol fatty ester. But, none of the exemplified compositions contain an active ingredient mixture wherein the nonionic detergent is present in major proportion which is probably due to the low foaming properties of the polyoxybutylene polyoxyethylene nonionic detergent.
U.S. Pat. No. 4,595,526 comprising a nonionic surfactant, a betaine surfactant, an anionic surfactant and a C 12 -C 14 fatty acid monoethanolamide foam stabilizer.
U.S. Pat. No. 6,147,039 teaches an antibacterial hand cleaning composition having a low surfactant content.
SUMMARY OF THE INVENTION
It has now been found that a liquid dish cleaning composition which has desirable cleaning and foaming properties that can also be antibacterial can be formulated with a sulfonate surfactant, an alkyl sulfate surfactant, a solubilizer, polyethylene glycol, a magnesium inorganic salt, a proton donating agent, hydrogen peroxide, and water.
An object of this invention is to provide a liquid dish cleaning composition that can also be antibacterial which comprises a sulfate anionic surfactant, a sulfonate anionic surfactants, a solubilizer, polyethylene, hydrogen peroxide, a proton donating agent, a magnesium inorganic salt and water, wherein the composition does not contain any silicas, abrasives, acyl isoethionate, 2-hydroxy-4,2′,4′-trichloridiphenyl ether, phosphoric acid, phosphonic acid, boric acid, alkali metal carbonates, alkaline earth metal carbonates, alkyl glycine surfactant, cyclic imidinium surfactant, or more than 3 wt. % of a fatty acid or salt thereof.
Another object of this invention is to provide a liquid dish cleaning composition with desirable high foaming and cleaning properties which kills also bacteria.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.
DETAILED DESCRIPTION OF THE INVENTION
This invention relates to a liquid dish cleaning composition that can also be antibacterial, which comprises approximately by weight:
(a) 16% to 30% of an alkali metal, ammonium or alkaline earth metal salt such as sodium salt of a sulfonate surfactant;
(b) 7% to 16% of an alkali metal or ammonium salt such as sodium of an alkyl sulfate surfactant;
(c) 0 to 5% of a magnesium inorganic salt;
(d) 0 to 10% of a solubilizer;
(e) 0.1% to 5% of a proton donating agent;
(f) 0.05% to 5% of hydrogen peroxide;
(g) 0% to 5% of polyethylene glycol; and
(h) the balance being water, wherein the composition has a pH of 3 to 6, more preferably 3.5 to 5.5 and has a viscosity of 100 to 1,000 cps, more preferably 150 to 500 cps at 25° C. using a #2 spindle at 50 rpm as measured on a Brookfield RVTDV-II viscometer, wherein the composition does not contain any grease release agents such as choline, chloride or buffering system which is a nitrogenous buffer which is ammonium or alkaline earth carbonate, amine oxide surfactants, guanidine derivates, alkoxylalkyl amines and alkyleneamines C 3 -C 7 alkyl and alkenyl monobasic and dibasic acids such as C 4 -C 7 aliphatic carboxylic diacids which do not contain a hydroxy group, boric acid, phosphoric acid, zwitterionic surfactant, amino alkylene phosphonic acid and alkyl polyglucoside surfactants and the composition is pourable and not a gel and has a complex viscosity at 1 rads −1 of less than 0.4 Pascal seconds.
The anionic sulfonate surfactants which may be used in the detergent of this invention are selected from the consisting of water soluble and include the sodium, potassium, ammonium, magnesium and ethanolammonium salts of linear C 8 -C 16 alkyl benzene sulfonates; C 10 -C 20 paraffin sulfonates, alpha olefin sulfonates containing about 10-24 carbon atoms and C 8 -C 18 alkyl sulfates and mixtures thereof.
The paraffin sulfonates may be monosulfonates or di-sulfonates and usually are mixtures thereof, obtained by sulfonating paraffins of 10 to 20 carbon atoms. Preferred paraffin sulfonates are those of C 12-18 carbon atoms chains, and more preferably they are of C 14-17 chains. Paraffin sulfonates that have the sulfonate group(s) distributed along the paraffin chain are described in U.S. Pat. Nos. 2,503,280; 2,507,088; 3,260,744; and 3,372,188; and also in German Patent 735,096. Such compounds may be made to specifications and desirably the content of paraffin sulfonates outside the C 14-17 range will be minor and will be minimized, as will be any contents of di- or poly-sulfonates.
Examples of suitable other sulfonated anionic detergents are the well known higher alkyl mononuclear aromatic sulfonates, such as the higher alkylbenzene sulfonates containing 9 to 18 or preferably 9 to 16 carbon atoms in the higher alkyl group in a straight or branched chain, or C 8-15 alkyl toluene sulfonates. A preferred alkylbenzene sulfonate is a linear alkylbenzene sulfonate having a higher content of 3-phenyl (or higher) isomers and a correspondingly lower content (well below 50%) of 2-phenyl (or lower) isomers, such as those sulfonates wherein the benzene ring is attached mostly at the 3 or higher (for example 4, 5, 6 or 7) position of the alkyl group and the content of the isomers in which the benzene ring is attached in the 2 or 1 position is correspondingly low. Preferred materials are set forth in U.S. Pat. No. 3,320,174, especially those in which the alkyls are of 10 to 13 carbon atoms.
The C 8-18 ethoxylated alkyl ether sulfate surfactants have the structure
wherein n is about 1 to about 22 more preferably 1 to 3 and R is an alkyl group having about 8 to about 18 carbon atoms, more preferably 12 to 15 and natural cuts, for example, C 12-14 or C 12-16 and M is an ammonium cation or a metal cation, most preferably sodium.
The ethoxylated alkyl ether sulfate may be made by sulfating the condensation product of ethylene oxide and C 8-10 alkanol, and neutralizing the resultant product. The ethoxylated alkyl ether sulfates differ from one another in the number of carbon atoms in the alcohols and in the number of moles of ethylene oxide reacted with one mole of such alcohol. Preferred ethoxylated alkyl ether polyethenoxy sulfates contain 12 to 15 carbon atoms in the alcohols and in the alkyl groups thereof, e.g., sodium myristyl (3 EO) sulfate.
Ethoxylated C 8-18 alkylphenyl ether sulfates containing from 2 to 6 moles of ethylene oxide in the molecule are also suitable for use in the invention compositions. These detergents can be prepared by reacting an alkyl phenol with 2 to 6 moles of ethylene oxide and sulfating and neutralizing the resultant ethoxylated alkylphenol. The concentration of the ethoxylated alkyl ether sulfate surfactant is about 1 to about 8 wt. %.
The proton donating agent is selected from the group consisting of inorganic acids such as sulfuric acid and hydrochloric acid and hydroxy containing organic acid, preferably a hydroxy aliphatic acid, which are selected from the group consisting of lactic acid or citric acid, orthohydroxy benzoic acid , salicylic or glycolic and mixtures thereof.
Polyethylene glycol which is used in the instant composition has a molecular weight of 200 to 1,000, wherein the polyethylene glycol has the structure
HO(CH 2 CH 2 O) n H
wherein n is 4 to 52. The concentration of the polyethylene glycol in the instant composition is 0 to 5 wt. %, more preferably 0.1 wt. % to 5 wt. %.
The major class of compounds found to provide highly suitable cosurfactants over temperature ranges extending from 5° C. to 43° C. for instance are water-soluble polyethylene glycols having a molecular weight of 150 to 1000, polypropylene glycol of the formula HO(CH 3 CHCH 2 O) n H wherein n is a number from 2 to 18, mixtures of polyethylene glycol and polypropylene glycol (Synalox) and mono and di C 1 -C 6 alkyl ethers and esters of ethylene glycol and propylene glycol having the structural formulas R(X) n OH, R 1 (X) n OH, R(X) n OR and R 1 (X) n OR 1 wherein R is C 1 -C 6 alkyl group, R 1 is C 2 -C 4 acyl group, X is (OCH 2 CH 2 ) or (OCH 2 (CH 3 )CH) and n is a number from 1 to 4, diethylene glycol, triethylene glycol, an alkyl lactate, wherein the alkyl group has 1 to 6 carbon atoms, 1methoxy-2-propanol, 1methoxy-3-propanol, and 1methoxy 2-, 3- or 4-butanol.
Representative members of the polypropylene glycol include dipropylene glycol and polypropylene glycol having a molecular weight of 150 to 1000, e.g., polypropylene glycol 400. Other satisfactory glycol ethers are ethylene glycol monobutyl ether (butyl cellosolve), diethylene glycol monobutyl ether (butyl carbitol), triethylene glycol monobutyl ether, mono, di, tri propylene glycol monobutyl ether, tetraethylene glycol monobutyl ether, mono, di, tripropylene glycol monomethyl ether, propylene glycol monomethyl ether, ethylene glycol monohexyl ether, diethylene glycol monohexyl ether, propylene glycol tertiary butyl ether, ethylene glycol monoethyl ether, ethylene glycol monomethyl ether, ethylene glycol monopropyl ether, ethylene glycol monopentyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monopentyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monopropyl ether, triethylene glycol monopentyl ether, triethylene glycol monohexyl ether, mono, di, tripropylene glycol monoethyl ether, mono, di tripropylene glycol monopropyl ether, mono, di, tripropylene glycol monopentyl ether, mono, di, tripropylene glycol monohexyl ether, mono, di, tributylene glycol mono methyl ether, mono, di, tributylene glycol monoethyl ether, mono, di, tributylene glycol monopropyl ether, mono, di, tributylene glycol monobutyl ether, mono, di, tributylene glycol monopentyl ether and mono, di, tributylene glycol monohexyl ether, ethylene glycol monoacetate and dipropylene glycol propionate.
The magnesium inorganic salt is selected from the group consisting of magnesium sulfate heptahydrate, magnesium oxide and magnesium chloride and mixture thereof.
The instant light duty liquid nonmicroemulsion compositions can contain about 0 wt. % to about 10 wt. %, more preferably about 1 wt. % to about 8 wt. %, of at least one solubilizing agent selected from the group consisting of a C 2-5 mono, dihydroxy or polyhydroxy alkanols such as ethanol, isopropanol, glycerol ethylene glycol, diethylene glycol, propylene glycol, and hexylene glycol and mixtures thereof and alkali metal cumene or xylene sulfonates such as sodium cumene sulfonate and sodium xylene sulfonate. The solubilizing agents are included in order to control low temperature cloud clear properties.
The instant formulas explicitly exclude alkali metal silicates and alkali metal builders such as alkali metal polyphosphates, alkali metal carbonates, alkali metal phosphonates and alkali metal citrates because these materials, if used in the instant composition, would cause the composition to have a high pH as well as leaving residue on the surface being cleaned.
The final essential ingredient in the inventive compositions having improved interfacial tension properties is water. The proportion of water in the compositions generally is in the range of 10% to 95%.
The liquid cleaning composition of this invention may, if desired, also contain other components either to provide additional effect or to make the product more attractive to the consumer. The following are mentioned by way of example: Colors or dyes in amounts up to 0.5% by weight; bactericides in amounts up to 1% by weight; preservatives or antioxidizing agents, such as formalin, 5-bromo-5-nitro-dioxan-1,3; 5-chloro-2-methyl-4-isothaliazolin-3-one, 2,6-di-tert.butyl-p-cresol, etc., in amounts up to 2% by weight; and pH adjusting agents, such as citric acid or sodium hydroxide, as needed. Furthermore, if opaque compositions are desired, up to 4% by weight of an opacifier may be added.
In final form, the instant compositions exhibit stability at reduced and increased temperatures. More specifically, such compositions remain clear and stable in the range of 0° C. to 50° C., especially 4° C. to 43° C. Such compositions exhibit a pH of 3 to 6, more preferably 3.5 to 5.5. The liquid cleaning compositions are readily pourable and exhibit a viscosity in the range of 100 to 1000 millipascal.second (mPas.) as measured at 25° C. with a Brookfield RVTDV-II Viscometer using a #2 spindle rotating at 50 RPM. Preferably, the viscosity is 150 to 500 mPas.
The following examples illustrate the hand dish cleaning compositions of the described invention. Unless otherwise specified, all percentages are by weight. The exemplified compositions are illustrative only and do not limit the scope of the invention. Unless otherwise specified, the proportions in the examples and elsewhere in the specification are by weight.
EXAMPLE 1
The following composition in wt. % was prepared by simple mixing procedure:
A
B
C
D
Na C14-C17 paraffin sulfonate
22.67
22.67
22.67
22.67
C12-C13 paraffin sulfate
11.33
11.33
11.33
11.33
Dipropylene glycol methyl ether
1.0
1.0
1.0
1.0
Hydrogen peroxide (35%)
0
0.5
0.5
1
Lactic acid
2.5
2.5
2.5
2.5
Polyethylene glycol 600
1.5
1.5
1.5
1.5
MgSO4.7H2O
2.0
2.0
2.0
2.0
Fragrance
0.4
0.4
0.4
0.4
Water
pH
3.5
3.5
4.5
4.5 | An antibacterial liquid dish cleaning composition with desirable cleansing properties comprising an alkyl sulfate, a sulfonate surfactant, a solubilizer, a proton donating agent, polyethylene glycol, hydrogen peroxide, a magnesium inorganic salt and water. | 2 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to quantum cryptography, and in particular to actively stabilized quantum key distribution (QKD) systems.
BACKGROUND ART
[0002] QKD involves establishing a key between a sender (“Alice”) and a receiver (“Bob”) by using either single-photons or weak (e.g., 0.1 photon on average) optical signals (pulses) called “qubits” or “quantum signals” transmitted over a “quantum channel.” Unlike classical cryptography whose security depends on computational impracticality, the security of quantum cryptography is based on the quantum mechanical principle that any measurement of a quantum system in an unknown state will modify its state. As a consequence, an eavesdropper (“Eve”) that attempts to intercept or otherwise measure the exchanged qubits will introduce errors that reveal her presence.
[0003] The general principles of quantum cryptography were first set forth by Bennett and Brassard in their article “Quantum Cryptography: Public key distribution and coin tossing,” Proceedings of the International Conference on Computers, Systems and Signal Processing, Bangalore, India, 1984, pp. 175-179 (IEEE, New York, 1984). Specific QKD systems are described in U.S. Pat. No. 5,307,410 to Bennett (“the '410 patent”) and in the article by C. H. Bennett entitled “Quantum Cryptography Using Any Two Non-Orthogonal States”, Phys. Rev. Lett. 68 3121 (1992), both of which are incorporated by reference herein. The general process for performing QKD is described in the book by Bouwmeester et al., “The Physics of Quantum Information,” Springer-Verlag 2001, in Section 2.3, pages 27-33 (“Bouwmeester”), which is incorporated by reference herein by way of background information.
[0004] The typical so-called “one way” QKD system, such as disclosed in the '410 patent, uses a “shared interferometer” consisting of a pair of unbalanced interferometers with precisely matched differential optical path lengths. The first unbalanced interferometer, located with Alice, splits a single photon into two spatially separated wave packets and the second unbalanced interferometer, located in Bob, brings the two wave packets together and interferes them. Because the two unbalanced interferometers are located remotely from each other, slight mismatches in the differential optical path lengths can arise from local environmental effects, including thermal fluctuations, acoustic noise, and vibrations. A mismatch in the differential optical path lengths result in a phase error that reduces the degree of interference of the single-photon-level optical pulses (“quantum pulses”). This in turn increases the quantum bit-error rate (QBER), which reduces the efficiency of the QKD process.
[0005] A one-way QKD systems needs to be stabilized to maintain the optical path-length balance of Alice and Bob's shared interferometer to within a fraction of the wavelength (e.g., ˜30 nm for 1.5 um light). Generally, this can be accomplished by passing “control” pulses (i.e., multi-photon “classical” optical pulses) through the shared interferometer at one QKD station (e.g., Alice) and detecting it at the output of the other QKD station (e.g., Bob). The QKD system is configured so that the classical optical pulses follow the same optical path traversed by the quantum pulses. Consequently, it is possible to monitor the phase error superimposed upon the qubits by observing the interference of the classical signals at the output of the interferometer. Using error signals generated by these interference patterns, it is possible to produce negative feedback for an actuator adapted to counteract this phase error. In response to the feedback signal, the actuator creates a compensating phase change at a single location (e.g., at Bob) to restore the optical path length balance. An example of an actively stabilized one-way QKD system is described in WIPO PCT Patent Application Publication No. WO2005067189 A1, entitled “Active stabilization of a one-way QKD system,” published on Jul. 21, 2005, which patent application is incorporated by reference herein.
[0006] One prior art approach to actively stabilizing a QKD system uses relatively weak (i.e., on the order of 25 photons) synchronous control signals of the same wavelength as the quantum signal. Since these classical control signals are at the same wavelength as the quantum signals, only time multiplexing can be used to separate them. The control signal intensity must be kept close to the single photon level when using gated-Geiger-mode avalanche photodiodes (APDs) as single photon detectors (SPDs). Since SPDs are still sensitive photo-detectors during the time intervals between gating pulses, any classical signals reaching them generate an enormous number of electrons, some of which become trapped in the APD junction and cause spontaneous avalanches as soon as gating pulses are applied. This causes a very high effective dark count rate. Because of its low intensity, the control signal must also be detected by its own, separate single photon detector(s). The control and quantum signal SPDs both share the same limitations so they are operated at the same repetition rate, namely, one stabilization pulse per quantum bit period.
[0007] Due to the binary output nature of single photon detectors, a meaningful feedback signal useful for compensating for interferometer phase drift can only be made by integrating over a relatively large number of samples (e.g., 100 samples). This increases the signal-to-noise ratio (SNR) at the expense of tracking bandwidth. For a qubit rate of 100 KHz and a 100-sample integration time, the system can be compensated only to 1 ms, which corresponds to rather weak 1 KHz vibrations. If the vibration amplitude is stronger, the system may not be able to track it, which leads to an increase in the QBER.
[0008] Another prior art approach uses a separate wavelength for the control signal. This allows the use of higher power control pulses because wavelength filtering prevents these signals from arriving at the SPDs. Higher power control signals allow the use of linear detection of the control signal, relieving the need to integrate over many periods. However, this approach uses a control signal pulse rate significantly lower than the quantum signal pulse rate (by a factor of 1/10). While this may provide satisfactory operation for laboratory and experimental conditions, it does not provide sufficient bandwidth for a commercially viable QKD system that requires tracking high-frequency, high-amplitude vibrations, such as for example, those coupled into the interferometers by system fan noise.
[0009] Another prior art approach is to use a planar lightwave circuit (PLC) based unbalanced Mach-Zehnder interferometers for Alice and Bob's interferometers. Each interferometer is integrated onto a silica chip that is temperature stabilized to 0.01° C., which provides sufficient stability for low QBER. The main disadvantages of this approach, however, are the higher excess loss of these interferometers compared to fiber based interferometers and the fact these components are not readily available and are difficult to manufacture.
SUMMARY OF THE INVENTION
[0010] The present invention is directed to systems and methods for performing quantum key distribution (QKD) that allow for an improved signal-to-noise ratio (SNR) when providing active compensation of the system's relative optical paths. The method includes generating a train of quantum signals having a first wavelength and interspersing at least one and preferably a relatively large number of strong control signals having a second wavelength in between the quantum signals. Only the quantum signals are modulated when the quantum and control signals travel over the first optical path at Alice. The quantum and control signals are sent to Bob, where only the quantum signals are modulated as both signal types travel over a second optical path at Bob. The control signals are directed to two different photodetectors by an optical splitter. The proportion of optical power detected by each photodetector represents the optical path difference (i.e., phase error) between the first and second optical paths. This difference is then compensated via a control signal sent to a path-length-adjusting (PLA) element in one of the optical paths. The strong control signals provides a high SNR that allows for commercially viable QKD system that can operate with a high qubit rate and a small qubit error rate (QBER) in the face of real-world sources of noise. Example embodiments using a fiber-based, phase-modulated QKD system and a PLA element in the form of an actuator residing in a section of optical fiber and that can change the phase of light passing therethrough, are discussed in detail below.
[0011] Additional features and advantages of the invention will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the invention as described herein, including the detailed description which follows, the claims, as well as the appended drawings.
[0012] It is to be understood that both the foregoing general description and the following detailed description present embodiments of the invention, and are intended to provide an overview or framework for understanding the nature and character of the invention as it is claimed. The accompanying drawings are included to provide a further understanding of the invention, and are incorporated into and constitute a part of this specification. The drawings illustrate various embodiments of the invention, and together with the description serve to explain the principles and operations of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a generalized schematic diagram of an actively compensated QKD system according to the present invention;
[0014] FIG. 2 is a schematic diagram of an example embodiment of Alice of the QKD system of FIG. 1 for carrying out the active-stabilization method of the present invention;
[0015] FIG. 3 is a schematic diagram of an example embodiment of Bob of the QKD system of FIG. 1 for carrying out the active-stabilization method of the present invention; and
[0016] FIG. 4 is a schematic timing diagram of the optical signals as present on the input optical fiber section at Alice's interferometer, illustrating the relatively large number of optically strong control signals for each quantum signal so as to provide a large signal-to-noise ratio (SNR) when measuring the phase error and generating the feedback control signal to correct the measured phase error based on the optical power detected from the classical signals rather than via SPD “clicks.”
[0017] The various elements depicted in the drawing are merely representational and are not necessarily drawn to scale. Certain sections thereof may be exaggerated, while others may be minimized. The drawing is intended to illustrate an example embodiment of the invention that can be understood and appropriately carried out by those of ordinary skill in the art. Where convenient, the same or like elements are given the same or like reference numbers.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0018] FIG. 1 is a schematic diagram of an actively stabilized QKD system 10 according to the present invention. QKD system 10 includes a QKD station Alice and a QKD station Bob that are optically coupled. In the example embodiment of FIG. 1 , Alice and Bob are optically coupled by an optical fiber link FL. Alice and Bob communicate by encoded single-photon-level quantum signals QS having a wavelength λ Q . The encoding may be any type of encoding that changes the state of the photon. Usually, polarization encoding or phase encoding is used, as described in Bouwmeester. The present invention applies to any type of encoding scheme and QKD system that requires active stabilization in order to maintain the qubit error rate (QBER) at an acceptable level. For example, in a polarization-based QKD system, a polarized control signal is sent over the optical fiber link FL and is used to determine changes in the polarization state over the QKD system optical path.
[0019] In the present invention, the active stabilization utilizes classical optical signals as control signals CS that have wavelength λ C ≠λ Q so that strong control signals can be used, as described below.
Phase-Encoding QKD System
[0020] An example embodiment of the active-stabilization method of the present invention is now described in connection with a phase-based QKD system 10 as illustrated in FIGS. 2 and 3 . As mentioned above and as will be apparent to one skilled in the art, the present invention applies to any actively compensated QKD system that employs optical signals separate from the quantum signals to measure system drift and to correct the drift.
Alice
[0021] With reference to FIG. 2 , Alice includes a “quantum light source” 20 adapted to generate quantum signals QS of wavelength λ Q . Alice also includes a classical (i.e., multi-photon) light source 22 adapted to generate control signals CS of wavelength λ C that are used for compensating the shared interferometer, as discussed below.
[0022] In one example embodiment, quantum light source 20 is in the form of a pulsed laser that is optically coupled to an attenuator 24 that attenuates output laser pulses P 0 to create quantum signals QS in the form of weak pulses (i.e., one photon or less, according to Poissonian statistics). In another example embodiment, quantum light source 20 is a single-photon light source that generates true single-photon quantum signals QS (which in this case are the same as output laser pulses P 0 ). For the case where the output of quantum light source 20 is already at the single photon level, attenuator 24 is not needed.
[0023] Alice further includes a wavelength division multiplexer (WDM) 40 A optically coupled to quantum light source 20 and to control signal light source 22 . WDM 40 A is also optically coupled to Alice's unbalanced interferometer 50 A via an input optical fiber section FA IN . Interferometer 50 A further includes an optical splitter 56 A to which optical fiber section FA IN is coupled and that forms two interferometer arms 62 A and 64 A that each includes a faraday mirror FM. A phase modulator MA is arranged in arm 64 A and an optical delay loop ODL A is arranged in arm 62 A forming an associated first differential optical path length ΔL A that can change due to environmental effects at Alice. The splitter 56 A splits each input pulse and upon exiting the interferometer one of the pulses is time delayed by ΔT=2·n·ΔL A /c where n is the index of refraction of the fiber, c is the speed of light in vacuum, and the factor of “2” is the result of the double pass through the delay loop. Modulator MA is adapted to impart a randomly selected phase to the quantum signal QS as part of the QKD process. Interferometer 60 A is optically coupled at optical splitter 56 A to optical fiber link FL via an output optical fiber section FA OUT and a second WDM 70 A. A synchronization light source 80 is also optically coupled to optical fiber link FL via WDM 70 A and generates synchronization signals SS that serve to synchronize the operation of Alice and Bob.
[0024] Alice also includes a controller CA that is electrically coupled to modulator MA, quantum light source 20 , control light source 22 , synchronization light source 80 and optical attenuator 24 , if such is present. An optical isolator 82 is arranged between optical splitter 56 A and WDM 70 A to ensure that light travels only one way from optical splitter to WDM 70 A.
Bob
[0025] Bob includes a WDM 70 B optically coupled at its input end to optical fiber link FL and at its output end to a synchronization detector 100 and to Bob's interferometer 50 B. Detector 100 is used to detect synchronization signals SS.
[0026] Bob's interferometer 50 B includes an optical splitter 56 B that, like Alice, has associated therewith input and output optical fiber sections FB IN and FB OUT . Optical splitter 56 B forms two interferometer arms 62 B and 64 B that each includes a Faraday mirror FM. Interferometer 60 B has associated therewith a second differential optical path length ΔL B formed by the presence of ODL B arranged together with an electronically controlled path-length-adjusting (PLA) member 110 in arm 62 B, such as an actuator. PLA member 110 is used to adjust the differential optical path length ΔL B in response to a feedback control signal S C . A phase modulator MB is arranged in arm 64 B and is used to impart a randomly selected phase to the quantum signal QS as part of the QKD process. Optical splitter 56 B has two outputs, with one output going to a first SPD SPD 1 and a first photodetector PD 1 via fiber section FB IN , a circulator 120 and a multiplexer 130 . The other output goes to a second SPD SPD 2 and a second photodetector PD 2 via FB OUT and multiplexer 132 .
[0027] The differential optical path length ΔL B of interferometer 50 B is required to exactly match ΔL A of interferometer 50 A to ensure ideal interference of the quantum signals. The actual values of ΔL A and ΔL B can vary as a function of the different environmental effects at Alice and Bob. However, at least one of the optical paths (here, the optical path at Bob) must be actively adjusted so that ΔL A =ΔL B .
[0028] Bob also has a controller CB, which in an example embodiment includes a processing unit 140 , a computer readable medium 141 , and other processing electronics (not shown) such as, for example, a field-programmable gate array (FPGA), adapted to control the operation of Bob (e.g., gating SPD 1 and SPD 2 ) in a manner that is synchronized with the operation of Alice. Controller CB is operably coupled to SPD 1 , SPD 2 , PD 1 , PD 2 , synchronization detector 100 , modulator MB, and PLA member 110 . The instructions for controlling the operation of Bob can be stored, for example, on computer-readable medium 141 , which in an example embodiment constitutes part of an FPGA.
Method of Operation
[0029] With reference to FIG. 2 and FIG. 3 , system 10 operates as follows. Controller CA sends a control signal S 80 to synchronization light source 80 , which in response thereto emits synchronization signals SS. Synchronization signals SS are multiplexed onto optical fiber link FL via WDM 70 A and travel over to Bob, where they are demultiplexed by WDM 70 B and detected by sync detector 100 . Sync detector 100 generates an electrical synchronization signal S 100 that is received by Bob's controller CB and is processed by processing unit 140 to establish the system timing and synchronization.
[0030] Alice sends control signals S 20 and S 22 to quantum light source 20 and control light source 22 , respectively, to cause these light sources to generate respective quantum signals QS and control signals CS. Here, control signals CS are not relatively weak (e.g., tens of photons) but rather are relatively strong (e.g., a thousand, many thousands, tens of thousands or millions of photons per signal). The allowable intensity of these pulses is dependent on the isolation provided by multiplexers 130 and 132 (which serve as filters), as well as the responses of the two SPDs.
[0031] Quantum and control signals QS and CS enter WDM 40 A and are multiplexed thereby and enter Alice's interferometer 50 A. Interferometer 50 A serves to split each optical pulse that enters it into two pulses separated by time delay ΔT=2·n·ΔL A /c where n is the index of refraction of the fiber, c is the speed of light in vacuum, and the factor of “2” is the result of the double pass in the delay loop. The quantum and control pulses then exit interferometer 50 A via output fiber FA OUT .
[0032] FIG. 4 is a schematic diagram illustrating the quantum and control signals QS and CS as multiplexed onto the input optical fiber section FA IN of interferometer 50 A. The quantum signals QS, with period T Q , have a low duty cycle which allows one or more control signals CS to fit between each quantum signal QS and be synchronous therewith. In an example embodiment, a relatively large number of control signals CS (e.g., greater than about 50, and preferably between from 50 to 100) are used when the time interval between the quantum signals permits. The selection of the control signal pulse period T CS is dependent on the time delay ΔT induced by interferometer 50 A and in the cleanest implementation is set so that T CS >2·ΔT. This condition prevents one pulse from overlapping the previous delayed pulse upon exiting Alice's or Bob's interferometer.
[0033] Interferometer 50 A also contains a phase modulator MA which is able to modulate the relative phase between any of the two time delayed pulses. For the security of the quantum key exchange it is vital that the phase modulation is applied only to the quantum signals. If the same phase encoding information were also imparted upon the control signals, then an eavesdropper could easily gain knowledge of the quantum key by measuring these classical signals while producing no indication of eavesdropping.
[0034] To prevent this, controller CA controls the output timing of the quantum and control signals QS and CS so that they do not overlap. Furthermore, the control signal transmission is interrupted for a brief period of time associated with the modulator activation at Alice and Bob called the modulator timing window TW (i.e., this signal lies outside of the timing window provided by modulator activation signal S A ). This is so that control signals CS are not passing through the modulators MA or MB while they are being activated to modulate the quantum signal QS. Quantum signal QS thus becomes a once-modulated quantum signal QS′ having received a phase modulation φ modA . The total phase difference between the two time delayed quantum signal pulses exiting Alice is Δφ Q =4π·n·ΔL A /λ Q −φ modA . The corresponding phase shift seen by the control signals which are not modulated is Δφ C =4π·n·ΔL A /λ C .
[0035] Control signals CS and the associated once-modulated quantum signal QS′ exit interferometer 50 A on output optical fiber section FA OUT and are optically coupled onto optical fiber link FL via WDM 70 . The quantum signal QS and the associated control signals CS then travel over to Bob via optical fiber link FL.
[0036] The quantum signal QS and the associated control signals CS enter Bob's interferometer 50 B via input optical fiber section FB IN . The once-modulated quantum signal QS′ is modulated again, receiving phase φ modB by modulator MB via a corresponding timed modulator activation signal SB provided by controller CB, thereby forming a twice-modulated quantum signal QS″. The total phase difference between the two interfering quantum pulses upon reaching coupler 56 B and interfering is Δφ Q =(4π·n·ΔL A /λ Q −φ modA )−(4π·n·ΔL B /λ Q −φ modB )=4π·n·(ΔL A −ΔL B )/λ Q +φ modB −φ modA . Again, the timing window TW leaves the control signals unmodulated so the phase difference between the interfering control pulses is simply Δφ C =4π·n·(ΔL A −ΔL B )/λ C . The operation of the control signal ensures that ΔL A −ΔL B =0 and remains stable which is accomplished by maintaining Δφ C at a constant value and checking the condition Δφ C =Δφ C when φ modB −φ modA =0.
[0037] Twice-modulated quantum signal QS″ and the associated control signals CS exit interferometer 60 B either via FB IN or FB OUT , depending on the overall phase modulation imparted to quantum signal QS″. For constructive interference, quantum signal QS″ is directed by optical splitter 56 B via fiber section FB IN to circulator 120 , which directs this signal to WDM 130 and to SPD 1 . Upon detecting a photon, SPD 1 in turn generates a first detection signal (click) SD 1 that is provided to controller CB. Likewise, for destructive interference, quantum signal QS″ is directed by optical splitter 56 B to output optical fiber section FB OUT , which directs this signal to WDM 132 and to SPD 2 . SPD 2 in turn generates a second detection signal (click) SD 2 that is provided to controller CB.
[0038] The many control signals CS associated with the quantum signal QS are directed equally by optical splitter 56 B to FB IN and FB OUT and to photodetectors PD 1 and PD 2 associated therewith when the OPL A =OPL B . To the extent OPL A ≠OPL B , then the amount of optical power directed to photodetectors PD 1 and PD 2 depends on the relative phase difference imparted to the control signals CS as they traversed the two interferometers. Corresponding photodetector signals SP 1 and SP 2 are provided to controller CB and are representative of the corresponding amounts of optical power detected at photodetectors PD 1 and PD 2 from the control signals CS. The detected control signals are then used to establish the phase error between interferometers 50 A and 50 B and to generate control (feedback) signal SC that causes PLA member 110 to compensate for the measured phase error.
[0039] The relatively large optical power associated with control signals CS, combined with their relatively large number per quantum signal, provides a very high SNR for the control signals. Since these signals are used to generate control signals SC to PLA member 110 as feedback signals, the high SNR makes the feedback process more robust and thus is able to better maintain a high extinction ratio for the coupled interferometers 50 A and 50 B. It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit and scope of the invention. Thus it is intended that the present invention cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. | Systems and methods for performing quantum key distribution (QKD) that allow for an improved signal-to-noise ratio (SNR) when providing active compensation for differences that arise in the system's relative optical paths. The method includes generating at one QKD station (Alice) a train of quantum signals having a first wavelength and interspersing one or more strong control signals having a second wavelength in between the quantum signals. Only the quantum signals are modulated when the quantum and control signals travel over the first optical path at Alice. The quantum and control signals are sent to Bob, where only the quantum signals are modulated as both signal types travel over a second optical path at Bob. The control signals are directed to two different photodetectors by an optical splitter. The proportion of optical power detected by each photodetector represents the optical path difference between the first and second optical paths. This difference is then compensated for via a control signal sent to a path-length-adjusting element in one of the optical paths. The control signals provides a high SNR that allows for commercially viable QKD system that can operate with a high qubit rate and a small qubit error rate (QBER) in the face of real-world sources of noise. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to an image forming apparatus which conducts image recording on a recording paper (a recording sheet) based on digital image information obtained by the use of a document image reading apparatus provided with an automatic document conveyance function. More specifically, the present invention relates to an image forming apparatus in which, if the above-mentioned recording paper is jammed, image recording can be resumed immediately utilizing image information stored in a storing means without re-reading the document image.
In the above-mentioned digital image forming apparatus, when copying is conducted using an ADF (automatic document feeder), if jamming occurred before a recording paper on which an image is recorded is discharged to outside the apparatus, in the same manner as in a so-called analogue image forming apparatus in which, by means of a reflected beam from the document, the surface of the photoreceptor is subjected to scanning and exposed, and then, an image formed on the surface of the photoreceptor is transferred onto the recording paper to be recorded, conventionally, before resuming copying after removing a jammed paper, the document corresponding to image recording onto the jammed paper must be returned to the start position of conveyance from the ADF. Therefore, there might occur errors during the return of the document to the ADF or the front surface and the rear surface of the recording paper might be mishandled so that operation was troublesome.
In addition, when recording images on both sides, if jamming occurred, it was necessary to re-read images for both sides.
SUMMARY OF THE INVENTION
The present invention was contrived for overcoming the above-mentioned problems on a digital image forming apparatus. According to the invention, copying is conducted using an ADF, if jamming occurs before a recording paper on which aforesaid images are formed is discharged to outside the apparatus, when copying is resumed after removing jammed paper, it is not necessary to return the document corresponding to image recording onto the jammed paper. It is an object of the invention to provide an image forming apparatus having favorable operability and copying efficiency and to provide a control method therefor.
Another objective is to provide an image forming apparatus having favorable operability and copying efficiency wherein, when double-sided copying is conducted, even if jamming occurs, image formation on the following document is conducted without re-reading an image for a double-side which has already been read and and makes it unnecessary to return the document when jamming occurs.
The above-mentioned objectives are attained by an image forming apparatus comprising a document conveyance means which successively conveys plural number of documents, a reading means which reads image information of aforesaid document, a storing means which temporarily stores double-sided image information by inputting image information from aforesaid reading means, plural toner image forming means which forms toner images on both sides of recording paper based on image information from the above-mentioned reading means or a storing means, a recording paper conveyance means which conveys a recording means, plural transfer means which transfers toner image on both sides of recording paper, a fixing means which heats collectively a recording paper in which toner images are formed on the above-mentioned both sides and fixes, a paper discharging means which discharges aforesaid recording paper outside the apparatus, a jamming detection means which detects jamming of recording paper conveyed by means of the above-mentioned recording paper conveyance means, a paper discharging means which informs paper discharging of the above-mentioned recording paper, a displaying means which informs the occurrence of jamming based on detection information of the above-mentioned jamming detection means and a copying control means which controls all of the above-mentioned means based on copying starting operation and which controls in such a manner that, when jamming detection information is inputted from the above-mentioned jamming detection means, image formation onto the first recording paper based on copying resumption operation thereafter is conducted based on image information for both sides which has been recorded onto a jammed paper stored in the above-mentioned storing means or which was planned to be recorded and temporary storing by the above-mentioned storing means is maintained until the above-mentioned paper discharging detection means detects discharging of the recording paper in which images of image information on both sides are formed.
In addition, the above-mentioned objectives are attained by a control method for controlling an image forming apparatus comprising a document conveyance means which successively conveys plural number of documents, a reading means which reads image information of aforesaid document, a storing means which temporarily stores double-sided image information by inputting image information from aforesaid reading means, plural toner image forming means which forms toner images on both sides of recording paper based on image information from the above-mentioned reading means or a storing means, a recording paper conveyance means which conveys a recording means, plural transfer means which transfers toner image on both sides of recording paper, a fixing means which heats collectively a recording paper in which toner images are formed on the above-mentioned both sides and fixes, a paper discharging means which discharges aforesaid recording paper outside the apparatus, a jamming detection means which detects jamming of recording paper conveyed by means of the above-mentioned recording paper conveyance means, a paper discharging means which informs paper discharging of the above-mentioned recording paper, a displaying means which informs the occurrence of jamming based on detection information of the above-mentioned jamming detection means and a copying control means which controls all of the above-mentioned means based on copying starting operation, wherein, when jamming detection information is inputted from the above-mentioned jamming detection means, image formation onto the first recording paper based on copying resumption operation thereafter is conducted based on image information for both sides which has been recorded onto a jammed paper stored in the above-mentioned storing means or which was planned to be recorded and temporary storing by the above-mentioned storing means is maintained until the above-mentioned paper discharging detection means detects discharging of the recording paper in which images of image information on both sides are formed.
Namely, in the above-mentioned image forming apparatus and its control method, image recording for the both sides of the initial recording paper after copying is resumed after jammed paper is removed is conducted based on image information from the temporary storing in the storing means until discharging of the recording paper on which an image has been recorded is detected by the discharging detection means. Therefore, it is not necessary to return a document which corresponds to image recording on the jammed paper to the starting position of the document.
In addition, the above-mentioned objectives are attained by a control method for controlling an image forming apparatus comprising a document conveyance means which successively conveys plural number of documents, a reading means which reads image information of aforesaid document, a storing means which temporarily stores double-sided image information by inputting image information from aforesaid reading means, plural toner image forming means which forms toner images on both sides of recording paper based on image information from the above-mentioned reading means or a storing means, a recording paper conveyance means which conveys a recording means, plural transfer means which transfers toner image on both sides of recording paper, a fixing means which heats collectively a recording paper in which toner images are formed on the above-mentioned both sides and fixes, a paper discharging means which discharges aforesaid recording paper outside the apparatus, a jamming detection means which detects jamming of recording paper conveyed by means of the above-mentioned recording paper conveyance means, a copying set number setting means, a paper discharging means which informs paper discharging of the above-mentioned recording paper, a displaying means which informs the occurrence of jamming based on detection information of the above-mentioned jamming detection means and a copying control means which controls all of the above-mentioned means based on copying starting operation, wherein, when jamming detection information is inputted from the above-mentioned jamming detection means, image formation onto the first recording paper based on copying resumption operation thereafter is conducted based on image information for both sides which has been recorded onto a jammed paper stored in the above-mentioned storing means or which was planned to be recorded and, when plural copying sets are set in the above-mentioned copying set number setting means, the above-mentioned storing means stores image information for both sides until the number of discharging recording paper detected by above-mentioned discharging detection means reaches the set number set in the above-mentioned copying set number setting means, images onto the recording paper for the second sheet and thereafter are formed based on image information stored in the above-mentioned storing means and the above-mentioned storing means stores image information for both sides until the number of discharging recording paper detected by above-mentioned discharging detection means reaches the set number set in the above-mentioned copying set number setting means.
Namely, in a control method of the above-mentioned image forming apparatus, double-sided image information onto the first recording paper after copying is resumed after jammed paper was removed is conducted based on image information stored by a storing means which has already recorded images on the jammed paper or which planned to record images on the jammed paper. Images are recorded based on image information from temporary storing by a storing means until discharging of the final recording paper of the copying set is detected by discharging detection means. Therefore, it is not necessary to return the document in which images were recorded on the jammed paper to the document starting position.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a cross sectional view of the first embodiment of an image forming apparatus of the present invention.
FIG. 2 shows side cross sectional view of an image carrier in FIG. 1.
FIG. 3 is a cross sectional view showing a constitution of an image reading device in FIG. 1.
FIG. 4 is a block diagram showing a control system of the first embodiment.
FIGS. 5(a) and 5(b) are illustrations showing formation status of double-sided toner.
FIGS. 6(a) and 6(b) are illustrations showing formation status of a single-sided toner image.
FIG. 7 shows an operation timing graph of each section of an image forming apparatus when copying set number is one.
FIG. 8 shows a cross sectional view of the second embodiment of an image forming apparatus of the present invention.
FIG. 9 shows an operation timing graph of each section of an image forming apparatus when copying set number is two.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Hereinafter, the embodiment of the present invention will be explained. Description of the following sentences does not limit technical scope or meaning of the terminology of Claims. In addition, definitive explanation of the embodiment of the present invention exhibits the best mode, and limits neither the meaning of terminology of the present invention nor the technical scope.
(Embodiment 1)
Overall and individual mechanisms of an image forming process of the first embodiment of an image forming apparatus of the present invention will be explained employing a color double-sided image forming apparatus of FIGS. 1 through 7. FIG. 1 shows a cross sectional view of a color double-sided image forming apparatus of the first embodiment of an image forming apparatus of the present invention. FIG. 2 shows a cross sectional side view of an image carrier of FIG. 1. FIG. 3 is a cross sectional view showing one example of an image reading device in FIG. 1. FIG. 4 is a block circuit diagram showing an example of a control system of the image forming apparatus in FIG. 1. FIGS. 5(a) and (b) and FIGS. 6(a) and (b) are drawings respectively showing toner formation status in the case of double-sided copying and single-sided copying. FIG. 7 shows a timing graph of operation of each section in the image forming apparatus when one set of documents are copied.
An image forming apparatus of FIG. 1 is provided with document conveyance section 5A which is an document conveyance means (ADF) operating automatically, document reading device 5 which is a reading means composed of scanning optical type document reading means 5B and image processing section 67, image memory 3 which is a storing means, image recording section composed of writing section 1A and image formation transfer section 1B having a toner image formation means, transfer means, a separation means, a fixing means and a cleaning means. In addition, it is constituted of transfer paper conveyance section and is provided with a selection means which selects the double-sided copy mode and the single-sided copy mode.
In a color double-sided image forming apparatus of Embodiment 1, image data which is image information of an document for each color is read by document reading device 5 provided above the apparatus main body of FIG. 1.
First, reading of an document will be explained.
In document reading device 5 in FIG. 3, documents D to be copied are stacked on document loading stand 50 from the lower side as page proceed while the front surfaces face downward. Due to operation of conveyance rollers 51 and fanning rollers 52, document D at the lowermost layer is conveyed to conveyance path 53 individually.
Conveyed document D removes guide tray G biased to a position exhibited by a continuous line to a position exhibited by a dashed line. Aforesaid document is fed onto a transparent platen glass 55 through conveyance belt 54. Aforesaid document temporarily stops at an document reading position while the front surface faces downward.
The surface image on document D on platen glass 55 is subjected to photo-scanning by means of illuminating and reading operation of first mirror unit 61 composed of illuminance lamp 63 constituting document reading section 5B and first mirror 64a at the speed of V and by means of movement of angled second mirror unit 62 in the identical direction as the movement of first mirror unit 61 at the speed of V/2. Aforesaid image is focused on three CCD line censors 66(B), 66(G) and 66(R) through dichroic prism 65 by means of image pickup lens 64. Image data which is image information of blue (B), green (G) and red (R) surface image focused on CCD line sensors 66(B), 66(G) and 66(R) after being subjected to color separation by dichronic prism 65 is converted to a digital signal by means of an analogue/digital conversion at image processing section 67. Following this, aforesaid signal is subjected to image processing such as a illuminance/density conversion, a filter processing, an expansion/reduction processing and a γ conversion and to conversion processing to image data of each color of yellow (Y), magenta (M), cyan (C) and black (B). Image data subjected to conversion processing is outputted to each exposure unit 12 in writing section 1A as an electrical signal by means of a control by copying control section 20 so that image formation for the first page is conducted on photoreceptor drum 10. Aforesaid image data are temporarily stored and housed in image memory 3 which is a storing means in FIG. 4.
If double-sided copying mode is selected and reading and forming images on double sides are conducted in document reading device 5, when image recording for the surface image (an image on the first page) for the first page of document D is finished, the head and the reverse of the document is reversed by means of a temporary reverse rotation of conveyance belt 54 through reversal paper feeding path 58 by means of control of copying control section 20, and then aforesaid document is fed onto platen glass 55 through conveyance belt 54 after passing conveyance path 53. Aforesaid document temporarily stops at an document reading position while the second page faces downward.
The image on the reverse surface (image on the second page) of document D located on platen glass 55 is read by the above-mentioned document reading section 5B, and then aforesaid image is subjected to the above-mentioned image processing in image processing section 67 in FIG. 4. Following this, image formation for the second page is conducted on photoreceptor drum 10. Image data on the second page is stored and housed in image memory 3 in the same manner as image data on the first page. Document D in which reading of double-sided image has been finished is discharged onto discharging tray 57.
When one-sided copying mode is selected and reading and forming of an image on one-side is conducted, an image on one side of document D on platen glass 55 is read by the above-mentioned document reading section 5B and aforesaid image is subjected to image processing by means of image processing section 67. Following this, aforesaid image is formed on photoreceptor drum 10. Aforesaid one-sided image data is stored and housed in image memory 3. Document D in which reading of one-sided image is finished is discharged onto discharging tray 57.
FIG. 4 is a block diagram showing a control system of the present embodiment. In FIG. 4, numeral 5 represents the above-mentioned document reading device, numeral 8 represents a copy control section having a key for designating either double-sided mode or a single-sided mode, a copy start button and a display section, numeral 20 represents a copy control section using a micro-computer which controls the entire image forming apparatus, numeral 21 represents an ROM which houses an image forming process program of each mode. Numeral 22 represents an RAM housed in copy control section 20. 23 represents a selector circuit A which selects one from image data directly sent from image processing section 67 or image data read from image memory 3 and sends it to the following circuit. 24 represents a mirror conversion circuit which converts image data for forming a mirror image. 25 represents selector circuit B which selects one from image data sent from selector circuit A23 or image data sent from mirror conversion circuit 24 and to sends it to writing section 1A.
Image memory has storage capacity for at least one sheet (2 pages) of document. When the double-sided copy mode is selected, image formation for the front surface and the rear surface is conducted on the first recording medium. Simultaneously with this, image data on the front surface and the rear surface are stored in image memory 3. Image data read by document reading section 5B is outputted to each exposure unit 12 of writing section 1A through selector circuit A23, mirror circuit 24 and selector circuit B25.
Based on image data read due to aforesaid process, an image on odd page of document D (the front surface image) or an image on even page surface (rear surface image) is formed on photoreceptor drum. 10. Aforesaid images are transferred on the front surface and the rear surface of the first recording medium P fed from paper feeding cassette 71A or 71A. Thus, copying cycle for the first page is finished. Recording medium P on which toner image is carried on the front surface and the rear surface is collectively fixed by a fixing device 17. Aforesaid recording medium is discharged on tray 22 located out of the apparatus. Aforesaid recording medium is stacked on a recording medium discharged in advance in paper order.
Image data on the front surface and the rear surface stored in image memory 3 is erased due to the control of copy control section 20 by means of information about judgment that recording medium P on which toner image formed based on aforesaid image data has been transferred and fixed has been discharged to out of the machine.
In image reading device 5, document D in which image reading has been finished is discharged onto tray 57 through discharging roller 56 due to the movement of conveyance belt 54.
In accordance with a copy mode instructed and set in operation section 8 in FIG. 4, by selecting an image forming method of a color double-sided image forming apparatus, i.e., either a double-sided copy mode or a single-sided copy mode, one copy mode selected from either program P1 which corresponds to the double-sided copy mode housed in ROM 21 through copy control section 20 or program P2 which corresponds to the single-sided copy mode is called in RAM 22. Control of the process of a color double-sided image forming apparatus as shown in FIG. 1 and execution are conducted.
Next, constitution of a color double-sided image forming apparatus in FIG. 1 and a color image forming method by means of a double-sided copy mode will be explained.
Toner image receiving body 14a described later is rotated in a dashed line arrowed direction a with the shaft of driving roller 14d as the center as shown in FIG. 1. The following image formation is conducted while aforesaid toner image receiving body 14a is separated from photoreceptor drum 10.
Photoreceptor drum 10, which is an image carrier, comprises a cylindrical substrate formed by a transparent member such as glass or transparent acrylic resin and provided thereon with a transparent conductive layer and a photosensitive layer such as an a-Si layer or an organic photosensitive layer (OPC) on the circumference of aforesaid substrate.
As shown in FIG. 2, photoreceptor drum 10 is sandwiched by front flange 10a and rear flange 10b. Front flange 10a and rear flange 10b are respectively provided on fixed shaft 110 through rollers 110a and 110b. Gear G provided on the circumference of rear flange 10b is engaged with a gear for driving (not illustrated). Due to force therefrom, photoreceptor drum 10 is rotated clockwisely as shown by an arrow in FIG. 1 while the transparent conductive layer is grounded.
In the present embodiment, the photoconductive layer on the photoreceptor drum may have exposure light amount capable of providing a suitable contrast. Therefore, light transmissive ratio of the transparent substrate of the photoreceptor drum in the present embodiment is not necessarily be 100%. It is allowed that a certain extent of light may be absorbed when exposed light transmits. As a material for a translucent substrate, those employ acrylic resin, specifically methacrylic acid methylester monomer for polymerization are excellent in terms of transparency, strength, accuracy and surface property. In addition, various translucent resins such as acrylic resin, fluoride resin, polyester resin, polycarbonate resin and polyethylene terephthalate resin which are ordinarily used for optical members are usable. They may be colored if they have translucency on exposed light. As a translucent conductive layer, indium tin oxide (ITO), tin oxide, lead oxide, indium oxide and copper iodide and metallic thin membrane composed of Au, Ag, Ni and Al which maintain translucency are used. As a casting method, a vacuum depositing method, an active reaction depositing method, each spattering method, each CVD method, a dip coating method and a spray coating method are utilized. As a photoconductive layer, an amorphous silicon (a-Si) alloy photosensitive layer, an amorphous selenium alloy photosensitive layer and each organic photosensitive layer (OPC) can be used.
Scorotron chargers 11, used as charging means, are used for image forming process for each of yellow (Y), magenta (M), cyan (C) and black (K). Aforesaid scorotron chargers are mounted in a direction perpendicular to photoreceptor drum 10, which is an image carrier, facing photoreceptor drum 10. By the use of a control grid kept at a prescribed potential against the above-mentioned organic photosensitive layer in photoreceptor drum 10 and a saw-tooth-shaped electrode, by means of corona discharge having the same polarity as the toner, charging is conducted (in the present embodiment, negative charge), giving uniform potential to photoreceptor drum 10. As a discharging electrode 11a, a wire electrode may be used.
Exposure position of exposure units 12, as an image exposure means for each color, are located between discharging electrode 11a of scorotron charger 11 and developing position of developing device 13 and upstream in the rotation of photoreceptor drum 13 compared with developing sleeve 131.
In exposure unit 12, bar-shaped exposure element 12a, in which several LED (light emission diode) as an image exposure light emission element arranged in a primary scanning direction parallel to shaft 110 of photoreceptor drum 10 in an array state, and Selfoc lens 12b, as a life size focusing element, are mounted on holder 12c. On cylindrical or prism-shaped retention member 20 provided integral to the apparatus main body, exposure unit 12, uniform exposure device 12C and exposure device 12D which functions simultaneously with transferring are mounted and housed in a substrate of photoreceptor drum 10.
As an exposure element, plural light emission elements such as FL (fluorescent light emitter), EL (electro-luminescence), PL (plasma discharger) and LED (light emission diode), which are aligned array shape for forming a bar-shape, are used. The range of light emission wavelength of light emission element used in the present embodiment is preferably 680-900 nm in which transmissivity of Y, M and C toners are ordinarily high. However, in this case, since image exposure is conducted from the rear surface, wavelength shorter than aforesaid wavelength range which has not sufficient transparency on color toner.
Each developing device is provided in accordance with the order of color formation in which images are formed. In the present embodiment, based on photoreceptor drum 10, Y and M developing devices 13 are located at the left side of aforesaid photoreceptor drum 10. C and K developing devices 13 are located at the left side of aforesaid photoreceptor drum 10. Y and M scorotron chargers 11 are located above of developing casing 138. C and K scorotron chargers 11 are located at the below of aforesaid developing casing 138.
Developing devices, which are developing means for each color, respectively house yellow (Y), magenta (M), cyan (C) and black (K) one-component or two-component developers. Aforesaid developing devices respectively provided a developing sleeve, formed by a cylindrical and un-magnetic material, made of stainless steel or aluminum, whose thickness is 0.5-1 mm and whose outer-diameter is 15-25 mm rotate in the identical direction as that of photoreceptor drum 10 at the developing position, while keeping a prescribed gap with photoreceptor drum 10, respectively.
Each developing device is kept un-contact with photoreceptor drum 10 having gap of a prescribed value, for example, 100-1000 μm, due to a pushing roller (not illustrated). When conducting developing operation by means of developing devices 13 for each color, development bias voltage (D.C. voltage or A.C. voltage was added to D.C. voltage) is impressed and, thereby jumping development by means of a one-component or two-component developer housed in developing device 13. Bias voltage in which A.C. voltage was superimposed on D.C. bias voltage having the same polarity as toner (in the present embodiment, a negative polarity) was impressed to photoreceptor drum 10 having a negative load in which a transparent conductive layer is grounded.
Each of the above-mentioned developing device 13 reversally develops electro-static latent image, on photoreceptor drum 10, formed by means of charging due to the above-mentioned scorotron charger 11 and image exposure due to exposure units 12 by the use of toner having the same polarity as charge polarity (in the present embodiment, photoreceptor drum 10 is negatively charged, therefore toner is negative polarity) under non-contact status by means of a non-contact developing method in which the above-mentioned development bias voltage is impressed.
When copying (image recording) is started due to depressing of copying starting button in operation section 8, toner image receiving body 14a (described later) is rotated in a direction shown by a dot arrow a with the shaft of driving roller 14d as the center. While aforesaid toner image receiving body is separated from photoreceptor drum 10, the photoreceptor driving motor (not illustrated) starts so that gear G provided on rear flange 10b on photoreceptor drum 10 is actuated through a gear for driving. Photoreceptor drum rotates clockwise in an arrowed direction as shown in FIG. 1. Simultaneously, provision of potential is started to photoreceptor drum 10 due to charging effect of Y scorotron charger 11 located upstream of developing casing of yellow (Y) developing device 13 at the left side of photoreceptor drum 10.
Simultaneously, in image reading device 5, insertion of document D into a document reading position is started. Image information on the surface (1st page) read from an image of document D which has stopped at the reading position is subjected to image processing to produce image data for Y, M, C and K colors. Aforesaid image data are directly inputted to exposure unit 12 as an electrical signal in such a manner that the image is exposed on a portion where the above-mentioned potential is provided. Simultaneously with this, image data for each color are temporarily stored in image memory 3.
Namely, after potential was provided on photoreceptor drum 10, in Y exposure unit 12, exposure by means of an electrical signal which corresponds to the first color signal, i.e., Y image data starts. Due to rotation scanning by the drum, an electro-static latent image which corresponds to Y image of document image on the photosensitive layer on the surface of the photoreceptor drum.
By means of Y developing device 13, the above-mentioned latent image is reversally developed while a developer on the development sleeve is in uncontact. In accordance with the rotation of photoreceptor drum 10, yellow (Y) toner image is formed.
Next, potential was provided on the above-mentioned yellow toner image on photoreceptor drum 10 due to charging operation by magenta (M) scorotron charger 11 located at the left side of photoreceptor drum 10, downstream of yellow (Y) developing device and upstream of developing casing 138 of magenta (M) developing device 13. Exposure by means of the second color signal, i.e., M image data, in M exposure unit 12 is conducted. Due to un-contact reversal development by means of M developing device 13, magenta (M) toner image is successively formed on the above-mentioned yellow (Y) toner image.
Cyan (C) toner image corresponding to the third color signal is formed on aforesaid yellow (Y) toner image due to cyan (C) scorotron charger 11 located at the right of photoreceptor drum 10 and above developing casing 138 of developing device 13, C exposure unit 12 and C developing device 13, and then black (K) toner image corresponding to the fourth color signal is formed on aforesaid cyan (C) toner image due to black (K) scorotron charger 11 located at the right of photoreceptor drum 10 and below developing casing 138 of developing device 13, K exposure unit 12 and K developing device 13. Thus, within one rotation of photoreceptor drum 10, color toner image is formed on the circumference thereof.
Exposure on the organic photosensitive layer by means of the above-mentioned Y, M, C and K exposure units 12 is conducted from inside of the drum through the above-mentioned transparent substrate. Accordingly, exposure of images corresponding to the second, third and fourth color signals does not receive influence from toner images formed in advance. Therefore, electro-static latent image identical to that of an image corresponding to the first color image can be formed. Due to heating of each exposure optical system 12, temperature inside photoreceptor drum 10 may rise. In order to stabilize temperature and prevent rise of temperature, materials having favorable heat transmissivity are used for the above-mentioned retention member 20, and a heater or a heat pipe is provided inside aforesaid retention member 20A. When the temperature is too low, a heat is used. When the temperature is too high, a heat pipe is used for releasing heat to outside the apparatus. Due to this, temperature can be inhibited so as not to cause trouble.
Next, toner image receiving body 14a is rotated in a dot arrow b with driving roller 14d as the center, and then is brought into contact with photoreceptor drum 10.
On the above-mentioned photoreceptor drum 10 (the first image carrier means), a color toner image, in which toner images are superposed, which will be an image on the first page is formed. The color toner image, which is an image for the first page, on photoreceptor drum 10 is collectively transferred on toner image receiving body 14a (the second image carrier means) by means of transfer device 14c in which voltage having an opposite polarity (in the present embodiment, a positive polarity) is impressed in transfer area 14b. In this occasion, in order to provide favorable transfer, uniform exposure by means of transfer-simultaneous-exposure device 12d is conducted using a light emission diode.
After the transfer, toner remained on the circumference of photoreceptor drum 10 is subjected to charge-eliminating by means of image carrier AC charge-eliminator 16. Following this, aforesaid toner is moved to cleaning device 19, where it is scraped out into cleaning device 19 by means of cleaning blade 19a composed of rubber material which is brought into contact with photoreceptor drum 10. By means of screw 19b, aforesaid toner is collected by a container for discharged toner (not illustrated).
In order to remove after-effect of the photoreceptor up to the former copying, charge on the photoreceptor from which remaining toner is removed by means of uniform exposure device 12c in which a light emission diode is employed.
Toner image receiving body 14a is rotated in a direction shown by dot arrow "b" in FIG. 1 with the shaft of driving roller 14d as the center, again. While aforesaid toner image receiving body 14a is separated from photoreceptor drum 10, an image on the second page, which is an image of an even page of the first sheet of a superposed color toner image, is formed on photoreceptor drum 10, being with an image on the first page formed on aforesaid toner image receiving body 14a. With regard to an image on the second page, it is necessary to modify image data in such a manner that the image on the second page forms a mirror with an image on the first page. Image data subjected to mirror conversion by means of mirror conversion circuit 24 due to copying control section 20 is sent to writing section 1A through selector circuit B25.
When an image on the second page is formed, toner image receiving body 14a is rotated in a direction shown by dot arrow "a" with the shaft of driving roller 14d as the center so that it is brought into contact with photoreceptor drum 10.
Recording paper P having a size designated by operation section 8 is fed from paper feeding cassette 71A or 71B due to control by copying control section 20, and is conveyed to timing roller 74 through feeding roller 73.
Recording paper P is fed to transfer area 14b due to driving of timing roller 74, while the color toner image for the second page carried on photoreceptor drum 10 is synchronized with the color toner image for the first page carried on toner image receiving body 14a. Recording paper P is charged to the polarity the same as the toner by means of paper charger 14f. Recording paper P is adsorbed by toner image receiving body 14a to be fed to transfer area 14b. By providing paper charging at the same polarity as toner, to pull with the toner image on toner image receiving body 14a or photoreceptor drum 10 each other is prevented, and thereby preventing the disturbance of the toner image.
By means of transfer device 14c which is the first transfer means on which voltage having the opposite polarity (in the present embodiment, a positive polarity) is impressed, images on the second page on the circumference of photoreceptor drum 10 are collectively transferred onto the upper surface of recording paper P. Here, the images for the first page on the circumference of toner image receiving body are not transferred onto recording paper P, remaining on aforesaid toner image receiving body 14a. By means of rear-surface transfer device 14g which is the second transfer means on which voltage having the opposite polarity (in the present embodiment, a positive polarity) is impressed, images on the first page on the circumference of toner image receiving body 14a are collectively transferred onto the lower surface of recording paper P. When transferring using transfer device 14c, in order to complete favorable transferring, uniform exposure, by the use of transfer-simultaneous-exposure device 12d using a light emission diode provided inside photoreceptor drum 10, which faces transfer device 14c, is conducted.
Since toner image for each color are superposed each other, in order to realize collective transfer, it is preferable that the toner on the upper layer(s) and that on the lower layer(s) are charged with the same charge amount and to the same polarity. Accordingly, in the case of double-sided image formation in which the color toner image formed on toner image receiving body 14a is subjected to inversion by means of corona discharge or in which the color toner image formed on the image carrier is subjected to inversion by means of corona discharge, toners on the lower layer(s) are not sufficiently charged so that transfer becomes insufficient.
To repeat reversal development on the image carrier, to collectively transfer color toner image in which toners having the same polarity are superposed for forming color toner onto toner image receiving body 14a without changing polarity and to collectively transfer aforesaid color toner image onto recording paper P without changing the polarity is preferable since it contributes to improvement of transfer property of image formation for the first page. For image formation for the second page, to repeat reversal development on the image carrier and to collectively transfer color toner image in which toners having the same polarity are superposed for forming color toner onto toner image receiving body 14a without changing polarity is preferable since it contributes to improvement of transfer property of image formation.
In the present image formation, a double-sided image formation method in which a color toner image is formed on the front surface of recording paper P by operating the first transfer means and a color toner image is formed on the rear surface of recording paper P by operating the second transfer means using the image forming method for the front surface and the rear surface for the above-mentioned recording paper P is preferably adopted.
Toner image receiving body 14a is made of an endless rubber belt having a thickness of 0.5-2.0 mm, composed of a silicone rubber or a urethane rubber semi-conductor substrate having a resistance value of 10 8 -10 12 Ω cm and provided thereon with a fluorine-coated anti-toner-filming layer having thickness of 5-50 μm. It is preferable that the upper layer also has similar semi-conductivity. In place of a rubber belt substrate, semi-conductive 0.1-0.5 mm width polyester, polystyrene, polyethylene and polyethylene terephthalate may be used.
Charge on recording paper P in which color toner images are formed on both surface is eliminated by means of paper separation AC charge-eliminator 14h as transfer separation use. Aforesaid recording paper P is separated from toner image receiving body 14a, and then conveyed to fixing device 17, as a fixing means, constituted on two rollers each having a heater inside both rollers. Between fixing roller 17a and pressure roller 17b, heat and pressure are applied. Due to this, adhered toners on the front surface and the rear surface of recording paper P are fixed. Aforesaid recording paper P (copy) in which images have been recorded on both surfaces is discharged to tray 76 outside apparatus.
The toner remained on the circumference of toner image receiving body 14a after transferring is subjected to cleaning by means of toner image receiving body cleaning device 14i. Toner remained on the circumference of photoreceptor drum 10 after transferring is subjected to charge-elimination by means of image carrier AC charge-eliminator 16. Following this, aforesaid toner moves to cleaning device 19, where aforesaid toner is scraped out into cleaning device 19 by cleaning blade 19a composed of rubber material which is brought into contact with photoreceptor drum 10 so that aforesaid toner is collected into a waster-toner container (not illustrated) by screw 19b. Photoreceptor drum 10 on which remaining toner is removed by means of cleaning device 19 is subjected to uniform charging by means of scorotron charger 11, and toner image receiving body 14a is rotated in a direction shown by dot arrow "a" in FIG. 1 with the shaft of driving roller 14d as the center, and then enters into the next image forming cycle while aforesaid toner image receiving body 14a is separated from photoreceptor drum 10.
The above-mentioned procedure shows a method of images forming on one sheet in a double-sided mode. When plural number of sheets, for example, n sheets are copied in the double-sided copying mode, as shown in FIG. 5(a), a color toner image on an even page formed on photoreceptor drum 10 and a color toner image on an odd page formed on toner image receiving body 14a are transferred on the front side and the rear side of recording paper P for producing a double-sided image. As shown in FIG. 5(b), the first sheet of double-sided copy is discharged on which the first page faces downward. The second sheet of copy is stacked on the first page copy. The final sheet of copy is stacked on the uppermost surface with (2n)th page toner image surface facing upward. Due to this, if documents D are stacked as page proceed from the bottom while the surface faces downward on document loading stand 50 of image reading device 5, copied recording papers P (copy) are stacked as pages proceed from the bottom while the surface faces downward.
In the case of color image formation in the single-sided copy mode, simultaneously as reading a single-sided image, images on one side is formed. In image memory 3, image data on one side are stored. When forming an image on a single-sided mode, a method to transfer and fix toner image carried on photoreceptor drum 10 (the first image carrier means) onto recording paper P by means of the above-mentioned toner image forming means, and then discharge aforesaid recording paper P onto tray 76 located outside he apparatus while facing the toner image surface upward is simple. I this occasion, toner image is formed only on photo-receptor drum 10, but not formed on toner image receiving body 14a.
When plural number, for example, n number of cop is conducted by a single-sided copy mode, as shown in FIG. 6(a), the first sheet of copy is discharged on tray 76 with color toner image facing upward. On aforesaid paper, second sheet of copy is discharged, and finally, (n)th sheet of copy is discharged on the uppermost side with the color toner image surface facing upward. Accordingly, copied papers are stacked in the reversal page number order. Therefore, in aforesaid single-sided copy mode, as shown in FIG. 6(b), documents D are loaded on document loading stand 50 as pages proceeds while facing the image surface upward, image reading starts from the final page. The copied papers are discharged as pages proceed while the toner image faces upward. Therefore, control becomes easier.
If s paper discharge switching means is provided at the discharging port of copy and thereby the front side and the rear side of copy paper is reversed to be discharged in the case of a single-sided copy mode, it is possible to stack and discharged as pages proceed in the normal page number order, both in double-sided copying and single-sided copying.
In the present embodiment, paper discharge sensor S1, which is a paper discharging detection means which detects discharge of the recording paper is provided in the vicinity of the discharging port for recording paper P. Discharging of recording paper P is detected by the falling of a recording paper detection signal from paper discharging sensor S1. Receiving a discharging signal of recording paper P from paper discharging sensor S1, copy control section 20 causes image memory 3 to erase an image signal on an image recorded on recording paper P stored when reading the document image.
As jamming detection means covering along with the conveyance path from the recording paper feeding section in cassette 71A or 71B to the discharging port of the recording paper, recording paper sensors S2 and S3 which detect passing of the recording paper and the above-mentioned paper discharging sensor S1 are provided. Copying control section 20 measures time until recording paper sensor S2 or S3 detects recording paper P which has been started conveyance and time until recording paper P detected by recording paper sensor S2 or S3 is detected by paper discharging sensor S1. If the measured times are respectively a prescribed time or more, it is judged to be that jamming has occurred. Displaying that aforesaid problem has occurred is shown in the display section of operation section 8. Operation on the upstream of the sensor which has detected the jamming of recording paper P is immediately stopped. With regard to the downstream side, operation is stopped after recording paper P existing inside the apparatus is discharged to out of the apparatus. Together with this operation, copying control section 20 stops the operation when document D fed from document loading stand 50 is discharged to document receiver 57 for document conveyance section 5A, when reading sequence of document D located on platen glass 55 is finished for document reading section 5B, when reading operation for one image is finished for writing section 1A for image recording section 1 or when photoreceptor drum 10 rotates one rotation additionally after writing operation of writing section 1A is finished for image forming and transfer section 1B, respectively.
When the operator removes jamming paper from recording paper conveyance section 7 and resumes copying operation by depressing a copying starting button in operation section 8, as shown in FIG. 7, even if feeding of document D onto platen glass 55 is conducted by document conveyance section 5A, document reading section 5B does not read the document immediately. Image data of an image which was recorded on a jammed paper stored in storing means 3 or which was planned to be recorded are called to be inputted in writing section 1A. Based on aforesaid image data, image forming and transferring section 1B, in the same manner as above, forms a toner image on photoreceptor drum 10. Aforesaid toner image is transferred onto recording paper P fed as if it is brought into contact with photoreceptor drum 10 by a recording paper conveyance section 7 to be fixed. Aforesaid recording paper is discharged to outside the apparatus.
When paper discharging sensor S1 detects that recording paper P after copying operation is resumed has been discharged to outside the apparatus, copying control section 20 erases image data stored in storing means 3, reads the next document on platen glass 55, conducts copying in image recording section 1 based on image data and records image data read in the following document onto storing means 3.
Embodiment 2
Image forming process and each mechanism of the second embodiment of the double-sided image forming apparatus of the present invention will now be explained referring to FIGS. 8 and 9. FIG. 8 shows cross sectional view of a color double-sided image forming apparatus, which is a second embodiment of a double-sided image forming apparatus of the present invention. FIG. 9 shows an operation timing graph of each section of an apparatus when the number of copying is two in the second embodiment.
In the same manner as in the first embodiment, an image forming apparatus of the second embodiment is an image forming apparatus provided with an image reading apparatus above the apparatus. Aforesaid image forming apparatus employs a semi-conductor laser emission element for an exposure unit and is provided with a key for inputting number of copying in operation unit 8. By means of aforesaid key and copying control section 20, a copying number setting means is constituted. With regard to other sections, they have the same functions and structures as of: the first embodiment. Therefore, those members having the same function and the structure as the first embodiment are provided with the same numerals and detailed explanation is omitted.
Next, the constitution of a color double-sided image forming apparatus and a color image forming method as shown in FIG. 8 are explained.
Toner image forming body 14a bridged between driving roller 14d and driven roller 14e is rotated in a direction shown by dot arrow in FIG. 8 with the shaft of driving roller 14d as the center, and the following image formation procedure is conducted while aforesaid toner image receiving body 14a is separated from photoreceptor drum 10.
Photoreceptor drum 10, an image forming body, comprises a cylindrical substrate inside thereof and provided thereon with photosensitive layers such as a conductive layer, a-Si layer or an organic photosensitive layer (OPC). While being grounded, aforesaid photoreceptor drum 10 is rotated clockwise as shown by an arrow in FIG. 8.
Photoreceptor drum 10, as an image forming body, is driven to be rotated. After-effect of the photoreceptor up to the former copying, charge on the photoreceptor from which remaining toner is removed by means of uniform exposure device 121a, as a charge-elimination means, composed of a light emission diode is eliminated so that charge in previous printing is eliminated.
Scorotron chargers 11, used as charging means, provide charging effect by means of corona discharge having the same polarity as the toner by the use of a control grid kept at a prescribed potential against the above-mentioned organic photosensitive layer in photoreceptor drum 10 and a saw-tooth-shaped electrode, charging is conducted (in the present embodiment, negative charge), giving uniform potential to photoreceptor drum 10.
After the circumference of photoreceptor drum 10 is uniformly charged, image exposure is conducted by an image signal due to exposure unit 121 as an image exposure means so that a latent image is formed on photoreceptor drum 10.
Exposure unit 121, as an image exposure means in writing section 1A is composed of a semi-conductor laser as a light emission element (not illustrated), rotation polygonal mirror 121b which rotates and scans laser light emitted from a semi-conductor laser, fθ lens 121c and reflection mirror 121d. Laser beam emitted from the semi-conductor laser (no illustrated) is subjected to rotational scanning by means of polygonal mirror 121b. The resulting beam conducts image exposure based on image data in the primary scanning direction parallel to the rotation axis of photoreceptor drum 10 which rotates through fθ lens 121c and reflection mirror 121d. In addition, due to secondary scanning of the rotation of photoreceptor drum 10, a latent image is formed on photoreceptor drum 10 due to secondary scanning by the rotation of photoreceptor drum 10.
On the circumference of photoreceptor drum 10, developing devices 13 for each color respectively containing a developer composed of yellow (Y), magenta (M), cyan (C) and black (K) toner and carrier are provided. In the same manner as in the first embodiment, first, development for the first color (for example, yellow) is conducted by development sleeve 131.
Following above, on the above-mentioned yellow (Y) toner image on photoreceptor drum 10, magenta toner image which corresponds to the second color signal, cyan (C) toner image which corresponds to the third color signal and black (K) toner image which corresponds to the fourth color signal are superposed to be formed during plural rotations.
Image forming and transfer section 1B is provide d with chargers 11 which uniformly charge photoreceptor drum 10, developing devices 13, first transfer device 14c, rear surface transfer device 14g which is the second transfer device, eliminator 14h which is a paper separation AC charge-eliminator, fixing device 17 and cleaning device 19. The above-mentioned toner image formed on photoreceptor drum 10 is transferred on the upper surface of recording paper P which has been fed in such a manner that it is brought into contact with photoreceptor drum 10 by means of recording paper conveyance section 7, which is the second page, by means of transfer device 14c. In this occasion, an image for the first page located on toner image receiving body 14a is not transferred onto recording paper P, and exists on toner image receiving body 14a. Next, by means of rear surface transfer device 14g, which is the second transfer means, in which voltage having an opposite polarity (in the present embodiment, a positive polarity) is impressed, an image for the first page located on the circumference of toner image receiving body 14a is collectively transferred onto the lower surface of recording paper P.
Recording paper P in which a double-sided copy mode is selected and a color toner image is formed on both sides of recording paper P is subjected to charge-elimination by means of paper separation AC charge eliminator 14h, and separated from toner image receiving body 14a. Aforesaid recording paper P is conveyed to fixing device 17 composed of two rollers each having a heater inside thereof. Between fixing roller 17a and pressure roller 17b, heat and pressure are applied. Due to this, toners adhered on the front surface and the rear surface of recording paper P are fixed so that images are recorded on both surfaces thereof. Aforesaid recording paper P (copy) is discharged to tray 76 outside the apparatus.
Toner remained on the circumference of toner image receiving body after the toner has been transferred is cleaned by toner image receiving body cleaning device 14i. Toner remained on photoreceptor drum 10 after the toner has been transferred is subjected to charge elimination by means of image carrier AC charge eliminator 16. Following this, aforesaid toner moves to cleaning device 19, and is scraped out into cleaning device 19 by cleaning blade 19a composed of rubber material which is brought into contact with photoreceptor drum 10. Aforesaid toner is collected by a waste toner container (not illustrated) by screw 19b. Photoreceptor drum 10 in which remaining toner has been removed by cleaning device 19 is subjected to uniform charging by scorotron chargers 11. Toner image receiving body 14a is rotated in a direction shown by dot arrow "a" in FIG. 1 with the shaft of driving roller 14d as the center, and then enters into the next image forming cycle while aforesaid toner image receiving body 14a is separated from photoreceptor drum 10.
In the present embodiment, paper discharge sensor S1, which is a paper discharging detection means which detects discharge of the recording paper is provided in the vicinity of the discharging port for recording paper P. Discharging of recording paper P is detected by the falling of a recording paper detection signal from paper discharging sensor S1. When detection frequency by paper discharging sensor S1 becomes equivalent to the number of copying set in operation section 8, copying control section 20 erases image data about an image recorded on recording paper P stored in image memory 3.
When copying number in the copying section is set in operation section 8, image reading of document D is not conducted when copying the second sheet. By outputting image data from the above-mentioned image memory 3 stored simultaneously with image reading, an image is formed. Due to the control by copying control section 20, image are transferred on an image on the odd page and on an image on the even page on the front surface and the rear surface of each recording paper P for the second sheet and thereafter fed from paper feeding cassette 71A or 71B which house recording paper P having a designated size. Recording paper P on which toner images are maintained on an even page and an odd page is fixed. Following this, in the same manner as in the above-mentioned embodiment 1, recording papers are stacked on recording paper ascendingly.
Copying control section 20 measures time until recording paper sensor S2 or S3, which are provided between recording paper P feeding point in cassette 71A or 71B, detects recording paper P and time until recording paper P detected by recording paper sensor S2 or S3 is detected by paper discharging sensor S1. If the measured times are respectively a prescribed time or more, it is judged to be that jamming has occurred. Aforesaid copying control section 20 displays that aforesaid problem has occurred is shown in the display section of operation section 8. Operation on the upstream of the sensor which has detected the jamming of recording paper P is immediately stopped. With regard to the downstream side, operation is stopped after recording paper P existing inside the apparatus is discharged to out of the apparatus. Together with this operation, copying control section 20 stops the operation when document D fed from document loading stand 50 is discharged to document receiver 57 for document conveyance section 5A, when reading sequence of document D located on platen glass 55 is finished for document reading section 5B, when reading operation for one image is finished for writing section 1A for image recording section 1 or when photoreceptor drum 10 rotates one rotation additionally after writing operation of writing section 1A is finished for image forming and transfer section 1B, respectively.
When the operator removes jamming paper from recording paper conveyance section 7 and resumes copying operation by depressing a copying starting button in operation section 8, as shown in FIG. 9, even if feeding of document D onto platen glass 55 is conducted by document conveyance section 5A, document reading section 5B does not read the document immediately. Image data of an image which was recorded on a jammed paper stored in image memory 3 or which was planned to be recorded are called to be inputted in writing section 1A. Based on aforesaid image data, image forming and transferring section 1B, in the same manner as above, forms a toner image on photoreceptor drum 10. Aforesaid toner image is transferred onto recording paper P fed as if it is brought into contact with photoreceptor drum 10 by a recording paper conveyance section 7 to be fixed. Aforesaid recording papers are repeated to be discharged to outside the apparatus. When copying control section 20 recognizes that the sum of the number of recording paper P discharged and the number of recording paper P before jamming is equal to the number of coping set in advance, image data on the front surface and the rear surface stored in image memory 3 are erased. By means of control by copying control section 20, reading of the next document on platen glass 55, copying operation (image recording operation) in image recording section 1 based on aforesaid image data and storage of the image data on the next document read onto image memory 3 are conducted.
According to an example shown in FIG. 9, it is not necessary to return documents corresponding to an image recording onto jammed paper. (copying operation after jamming is conducted by means of image data stored in image memory 3. In image memory 3, updated image data (for 2 pages for the double-sided copying mode, and for 1 page for the single-sided copying machine) read by document reading device 5 is stored. Aforesaid storage is erased by discharging detection information of set number of recording paper P in which an image based on the same image data is recorded. On the erased memory portion, next document image information read by document reading device 5 is stored. Therefore, image memory 3 may have a memory capacity for 2 pages. If image memory 3 has capacity capable of storing 3 or 4 pages, it is possible to read the next document for storing during recording an image. Thus, processing speed can be enhanced. Anyway, aforesaid apparatus can be composed at inexpensive cost.
In the above-mentioned explanation, image memory 3 stores image data of the next document on a space where updated image data has been erased. However, the following type may be used. Namely, in image memory 3, by storing image data of the next document on the updated image data, updated image data are substantially erased, and image data on the next document are newly stored.
In FIG. 9, timing between copying start or copying restart and start of feeding in document or recording paper P by means of ADF 5A and recording paper conveyance section 7, finish of discharge of recording paper P by means of recording paper conveyance section 7 and erasing of storage in image memory 3 and finish of reading data by means of document reading device 5 and start of feeding in document D by means of ADF 5A are coincide not because they are conducted simultaneously. It shows that there are cause-effect relationships that the latter are conducted since the former was conducted. In order to simplify explanation, FIG. 9 shows an operation timing graph of each section in the apparatus when copying number is 2. However, the mechanism is the same when the copying number is 3 or more.
In the present embodiment too, selection either a double-sided copying mode or a single-sided copying mode are conducted as explained in Embodiment 1. Depending upon modes adopted, image forming and discharging methods similar to those explained in FIGS. 5 and 6.
In the same manner as in Embodiment 1, in the double-sided copying mode, as shown in FIG. 5, when copying is conducted for n pages and plural sets, to make a double-sided image by transferring images formed on photoreceptor drum 10 and images formed on toner image receiving body 14a on the front surface and the rear surface of recording paper P of the first page is repeated for plural times. Accordingly, copies for the first page are discharged onto plural of different trays. In the same manner, copies for the 2nd page are discharged onto plural of different trays ascendingly.
In a single-sided image forming mode in which recording papers P to which copying has already been applied are discharged onto tray 76 with toner image surface facing upward, in the same manner as in Embodiment 1, the following simple method is used. Namely, toner images are formed only on photoreceptor drum 10, but not formed on toner image receiving body 14a.
The present invention was applied to a color double-sided image forming apparatus. However, the present invention can also be applied to a monochrome double-sided image forming apparatus.
As explained above, in an image forming apparatus of the present invention, an image can be formed in which an image can be recorded on a recording paper on a real-time basis with reading document image. Therefore, image recording speed (copying speed) is speedy. In addition, when jamming has occurred on a recording paper, the document for jammed recording paper may not be returned to the ADF document loading stand when copying is resumed. Therefore, there must not occur forgetting to return the document to the ADF document loading stand or erroneous returning. Without them, easily, copying operation can be resumed. In addition, in an image forming apparatus of the present invention, storing capacity of a storing means which stores image information is allowed to be small. Therefore, the cost for manufacturing aforesaid apparatus may be inexpensive.
According to a control method of the present invention, a similar effects as the above-mentioned image forming apparatus can be provided. In addition, it is sufficient that the capacity of the image memory may store image data for 2-4 pages even when double-sided copying is conducted. Therefore, processing speed can be enhanced.
According to a control method of the image forming apparatus of the present invention, even when plural copying sets are set, copying speed is so high. In addition, when jamming occurred on a recording paper, forgetting to return the document to the document loading stand can be prevented when resuming copying after removing jammed paper. Copying operation can be resumed easily. | An apparatus for forming images on at least one surface of a sheet includes a reader for reading image information on documents, a memory for storing image signals output by the reader, and an image forming unit for selectively forming one of: (i) two page toner images corresponding to the image signals of two pages of the documents separately on two image carrying members, and (ii) a single toner image on one of the two image carrying members. A jam detector detects a jammed sheet, and a delivery detector detects delivery of a copied sheet to outside the apparatus. Image signals are eliminated from memory in accordance with a progression of image formation. If the jam detector detects the occurrence of the jammed sheet, a control unit prohibits the memory from eliminating the image signals until the delivery detector detects a next sheet delivered from the apparatus, so that the selected image expected to be formed by the image forming unit on the jammed sheet may be properly formed on a following sheet based on the image signals retained in the memory. A selector is provided for selecting one of a both-surface copy mode and a single-surface copy mode, wherein the control unit controls the memory to store the image signals corresponding to two pages of the documents when the both-surface copy mode is selected and to store the image signals corresponding to the single page of the documents when the single-surface copy mode is selected. | 7 |
FIELD OF THE INVENTION
[0001] The present invention relates to a method and a system for notifying information, and more particularly to a method and a system for notifying presence information.
BACKGROUND OF THE INVENTION
[0002] At present, the presence service is in increasingly wide use. The presence service is a communication service that collects and issues presence information. Many people want to obtain presence information of a user of presence service, including the family and friends of the user, or even a stranger. However, much of the presence information may be the user's privacy. The presence service enables the user to utilize various terminals to look for a chat pal, to inquiry about the status information of the chat pal or the like beyond the restriction of space and time, so as to achieve an instant text and multimedia information exchange. A presence server is capable of presenting and managing the status of users. A user may know from the presence information whether the opposite party is online, what he is engaged with (e.g. a meeting, a dinner, etc.), his mood, client capability, hobbies or other information. The user may send invitations to other users to share media contents, such as a ring, a picture, a file, etc.
[0003] FIG. 1 illustrates a structure of a system for notifying presence information in the prior art. The system includes a presentity client or presentity application server, a presence server, a watcher client or watcher application server, and a presence XDMS (XML Document Management System). A presentity is a logical entity that has Presence Information associated with it. This Presence Information may be composed of a multitude of Presence Sources. A presentity is most commonly a reference for a person, although it may represent a role such as “help desk” or a resource such as “conference room #27”. The presentity is identified by a SIP URI (as defined in [RFC3261]), and may additionally be identified by a pres URI (as defined in [RFC3859]). A watcher is any uniquely identifiable entity that requests presence information about a presentity, from the presence service.
[0004] The presentity client or presentity application server is the source of presence information. When its presence information changes, the presentity client or presentity application server sends a PUBLISH message initiatively to the presence server, to publish the presence information.
[0005] The watcher client or watcher application server sends to the presence server a SUBSCRIBE message subscribing for the presence information from the presentity, and receives NOTIFY messages from the presence server.
[0006] The presence XDMS (XML Document Management System) stores authorization rules of the presentity (e.g. subscription authorization rules, content authorization rules, etc.), etc.
[0007] The presence server is the core of the system. It is capable of presenting and managing the status of users. It includes a subscription processing component, a storage component and a publication and notification processing component.
[0008] After receiving the SUBSCRIBE message from the watcher client or watcher application server, the subscription processing component obtains subscription authorization rules set in the presence XDMS by the corresponding presentity, determines the result of the subscription in accordance with the subscription authorization rules, and if the subscription is allowed, saves the subscription relationship in the storage component.
[0009] The storage component stores information including the subscription authorization rules, the subscription relationship, published content, etc.
[0010] After receiving a publish request sent from the presentity client or presentity application server, the publication and notification processing component retrieves a certain subscriber (a watcher) from the storage component and relevant rules set by the presentity and the watcher, processes the presence information in accordance with the relevant rules, and notifies the watcher client or watcher application server of the processed (composed, transformed, content-filtered, etc.) presence information.
[0011] The publication and notification processing component is the most important component in the presence server. Its structure is as illustrated in FIG. 2 . The publication and notification processing component further includes a presence information composition unit, a content authorization rules checking unit, a watcher filtering unit, a partial notification processing unit, and a presence information publication unit, all of which are connected sequentially.
[0012] The presence information composition unit is adapted to receive published information sent from the presentity client or presentity application server, and compose the presence information which is newly published with the presence information stored in the presence server.
[0013] The content authorization rules checking unit is adapted to filter off the information which is not allowed for publication in accordance with the rules set by the presentity client or presentity application server (e.g., rules that specify what information is allowed for publication with respect to a certain watcher client or a watcher application server).
[0014] The watcher filtering unit is adapted to filter off undesired presence information content (e.g., the watcher requires only the presence information related to the status of the user, other presence information will be filtered off) in accordance with an Event Notification Filtering rules set by the watcher (e.g., rules that specify which information of a certain presentity client or presentity application server is undesired).
[0015] The partial notification processing unit is adapted to filter off the information that is not subscribed in accordance with the rules set by the watcher client or presentity application server upon subscription (e.g., only subset of presence information relevant to the position of the user is subscribed).
[0016] The presence information publication unit is adapted to notify the watcher client or watcher application server of the processed presence information.
[0017] The above rules used by the publication and notification processing component are existing rules. The content authorization rules checking unit, the watcher filtering unit and the partial notification processing unit are all optional, and the connection sequence between them may be altered arbitrarily. If the presentity or the watcher hasn't set certain rules, the corresponding unit(s) may be omitted. Furthermore, the above rules in the prior art are all content related processing rules.
[0018] In the above system, the presentity application server and the watcher application server may be configured as one application server or may be configured separately as required.
[0019] The watcher client or watcher application server and the presentity client or presentity application server may be a SIP (Session Initiation Protocol) capable mobile terminal, such as a mobile phone, a PDA (Personal Digital Assistant), an intelligent terminal (e.g., a digital set-top box) or the like, or may be a fixed terminal capable of SIP. An application for presence information subscription is provided on the watcher client or watcher application server. A user may use this application to select information to be subscribed. After the information to be subscribed is determined, the watcher client or watcher application server may send such information to the presentity server along with the identity of the user.
[0020] According to the above solution, SUBSCRIBE and PUBLISH are both SIP messages. The field “From” in the SIP head of SUBSCRIBE indicates the identity of the watcher, and the field “To” indicates the identity of the presentity. If the message body is empty, all the presence information will be subscribed, and if the message body contains a partial subscription XML document, that document will specify the information to be subscribed. The subscription authorization rules in the prior art is described with an XML document including elements such as <Condition>, <Action> and <Transformation>. The element <Condition> represents matching conditions, including 1) Identity: identity of user, e.g., “sip:zhangsan@163.com”; 2) Domain, e.g., “@163.com”; the presence information, such as the status of an activity (e.g., in a meeting, a dinner, etc.), may be published for the users who match the condition <Condition> after they have subscribed successfully. The element <Action> represents an action to be performed when matched, including Allow, Block, Polite-Block (which returns the information of successful subscription, but never notifies the watcher any presence information. In other words, this is a friendly refusal with the same effect as Block) and Confirm (wait for confirmation). The element <Transformation> represents which information is allowed to be published for a watcher when the watcher has subscribed successfully. This is effective only during the publication and is controlled by the presentity, and determines which present information elements are allowed for publication and which are not allowed in accordance with only the pre-configuration of the presentity for the presence information. As a result, it is difficult to achieve dynamic control. For example, it is difficult to allow the notification of presence information in accordance with the status of the watcher or the presentity.
[0021] In the prior art, there are two solutions for the determination of presence information, i.e. partial subscription and event notification filter. The partial subscription means to specify the scope of presence information to be subscribed upon subscription, such as which type(s) of presence information to be subscribed, which part(s) of this type(s) of presence information to be subscribed, etc. The event notification filter refers to some filtering set by the watcher for the contents of presence information. For example, only presence information elements in compliance with a certain namespace may be received, etc.
[0022] A subscription request includes two parts, i.e., a “message head” and a “message body”. Here, the “message head” indicates the information of the watcher, the presentity, etc., and the “message body” contains an event notification filtering rules indicating the subscription scope (whether to subscribe all or partial of information of a certain type) of presence information. The event notification filtering rules are optional.
[0023] In the above solutions, the presence XDMS is separated from the presence server, and various rules are stored in the presence XDMS. The XDMS settings are presented and various rules are modified by the presentity client by using the XCAP protocol via an Aggregation Proxy, or by the presentity application server by using the XCAP protocol directly, or by the user via a human-machine interaction interface (e.g., a webpage). In the prior art, the presence XDMS may also be integrated with the presence server, and thus, various rules may be stored in the presence server.
[0024] A method for notifying presence information in the prior art will be described in detail with reference to FIG. 3 .
[0025] 1) A presentity A first sets some content-related processing rules at a presence XDMS, such as subscription authorization rules (which users are allowed for subscription), content authorization rules (what information is allowed for publication), etc. A presence server may obtain these rules through the XCAP protocol. Alternatively, if the presence server has subscribed for the notification of any change in these rules, the presence XDMS will notify the presence server when any of these rules is changed. The subscription authorization rules and the content authorization rules are stored in an XML file. The XML file includes three important elements <Condition>, <Action> and <Transformation>. The <Condition> represents a matching condition, and the <Action> represents a matching result (Allow, Block, Polite-Block and Confirm). The combination of <Condition> and <Action> constitutes the subscription authorization rules, and are utilized to process a subscription request from the watcher in accordance with the rules set by the presentity. The <Transformation> constitutes the content authorization rules, and is utilized to filter off or adapt the information which is not allowed for publication in accordance with the rules (what information is allowed to be published for a certain watcher) set by the presentity. For example, <namespace> used in the event notification filter indicates that the presence information in compliance with this namespace is subscribed, and <include> used in <what> indicates the presence information field(s) to be subscribed (Only some of event notification filtering conditions are described here as examples).
[0026] 2) A watcher B sends a SUBSCRIBE message to the presence server to subscribe the presence information of the presentity A.
[0027] 3) The presence server receives the SUBSCRIBE message from the watcher B, and then retrieves from the presence XDMS the subscription authorization rules set by the presentity A, and determines the subscription result in accordance with the subscription authorization rules. If the subscription is allowed, this subscription relationship may be stored.
[0028] 4) The presentity A sends a PUBLISH request to the presence server.
[0029] 5) The presence server receives the PUBLISH request sent from the presentity A, gets a certain subscriber (the watcher B) according to subscription relationship, retrieves the content-related processing rules set by the presentity A and the watcher B, and then publish in accordance with the content-related processing rules.
[0030] The process of publishing the presence information by the presence server in accordance with the content-related processing rules upon receiving the PUBLISH request sent from the presentity A includes the following steps:
[0031] 51) composing the presence information newly published and the presence information stored in the server;
[0032] 52) filtering off the information disallowed for publication in accordance with rules set by the presentity (e.g., rules that specify the information which is allowed to be published for a certain watcher client);
[0033] 53) filtering off the information beyond the scope of the subscription in accordance with rules set by the watcher upon subscription (e.g. rules that only the subset of the presence information related to the location of a user is subscribed); filtering off the undesired information in accordance with rules set by the watcher (e.g. a rule that specifies the undesired information from a certain presentity). For instance, the watcher desires only the presence information related to the status of a user, and other information will be filtered off;
[0034] 54) notifying watcher B of the processed presence information.
[0035] The above prior art solution has a drawback that the presentity cannot set notification conditions. It may be desirable for the presence user to set some authorization rules to further control the subscription and publication rather than just the content of presence information. In addition to a blacklist and a white list (e.g., users A and B are allowed, and user C is disallowed), the authorization rules may further include the number of times that the presence information is allowed to be published, the number of times that the presence information is allowed to be subscribed, etc. The presence information from the user cannot be obtained after a condition relevant to the number of times is exceeded. In particular, users may be charged for subscription of presence information published by a nonhuman presentity, such as a radio program, weather broadcast, a stock market information, etc. It may be desirable for the nonhuman presentity to set a free trial number of times (e.g. 100 pieces for free) or a free trial period (e.g. 8:00˜18:00, each day of Aug. 1, 2005˜Sep. 1, 2005) for publishing the presence information, as well as a number of times that the presence information is allowed to be subscribed (e.g. three times). For instance, if a watcher subscribes the presence information for the first time, the watcher may receive the presence information for free within a predetermined number of times that the information is allowed to be published or subscribed. However, when the number of times has been exceeded, and the watcher has not established a subscription relationship with a charge plan, the provision of the presence information may be terminated or the subscription may be blocked automatically, while the watcher may be added to the blacklist.
[0036] In addition, the presentity may wish not to publish the presence information to the watcher during some periods of time, which, however, would be impracticable in the prior art. For example, a boss has subscribed the presence information on the location of an employee, while the employee may desire to publish the presence information to the boss only during the working hours (e.g., effective from 8:00 to 18:00).
[0037] Furthermore, the presentity may also wish not to publish the presence information to the watcher when the presentity is in a particular status, which is also impracticable in the prior art. For example, the boss has subscribed the presence information on the location and the status of an employee. When the presentity is playing a game, he may change his presence status to the status “In Game”, and may have set in advance that the presence information in such a way that his status “In Game” will not be transmitted to the boss. Therefore, although the presentity publishes the presence information to the presence server, the presence server will not send the presence information to the subscriber, i.e. the boss, in accordance with the setting of the presentity.
SUMMARY OF THE INVENTION
[0038] The present invention provides a method and a system for notifying presence information, which may enable a presentity to set a publication period and a validity period for the presence information, a number of times that a subscriber may receive the information, a number of times that the subscriber may subscribe the information, and a presence server may determine whether to send notifications to a watcher in accordance with such conditions.
[0039] An embodiment of the present invention provides a method for notifying presence information which may include: transferring, by a presence server, to either one of a watcher client or watcher application server the presence information that is conformable to notification rules set by a presentity as well as content-related processing rules set by a watcher and the presentity, when receiving the presence information sent from either one of a presentity client or presentity application server.
[0040] Optionally, the notification rules may include: allowing presence information to be notified when notification time of the presence information is within a validity term and/or a prescribed publication period.
[0041] Optionally, the notification rules may include: allowing presence information to be notified when a receipt number of times of a watcher subscribing the presence information does not exceed a limit on number of times and/or a receipt frequency of the watcher does not exceed a transfer frequency.
[0042] Optionally, the notification rules may include: determining whether to publish the presence information in accordance with a status of the presentity.
[0043] Optionally, the content-related processing rules may include a maximum subscription times, and the presence information is allowed for subscription when the number of subscription is less than the maximum subscription times.
[0044] Optionally, the content-related processing rules set by the presentity may include: allowing a watcher to receive presence information when a receipt frequency and/or a receipt period of the watcher is within a scope.
[0045] Another embodiment of the present invention provides a system for notifying presence information which may include a presentity client or presentity application server, a presence server, a watcher client or watcher application server, and a presence XDMS (XML Document Management System). The presence server is adapted, upon receiving presence information sent from the presentity client or presentity application server, to transfer to the watcher client or watcher application server the presence information that is conformable to notification rules in the presence server or the presence XDMS by the presentity and content-related processing rules in the presence server or the presence XDMS by the presentity.
[0046] Optionally, the presence server may include a publication and notification processing component and notification rules processing component, and the publication and notification processing component is adapted to determine a watcher for receiving the presence information in accordance with the subscription relationship, to send to the notification rules processing component a query whether a presentity publishing the presence information has set notification rules, and to process the presence information in accordance with the content-related processing rules and a response returned from the notification rules processing component; and the notification rules processing component is adapted to, upon receiving the query sent from the publication and notification processing component whether the presentity publishing the presence information has set notification rules, determine whether the presentity has set the notification rules, and if yes, determine whether the notification rules are met in accordance and send the response to the publication and notification processing component.
[0047] Optionally, the notification rules may include: allowing presence information to be notified when notification time of the presence information is within a validity term and/or a prescribed publication period.
[0048] Optionally, the notification rules may include: allowing presence information to be notified when a receipt number of times of a watcher subscribing the presence information does not exceed a limit on number of times and/or a receipt frequency of the watcher does not exceed a transfer frequency.
[0049] Optionally, the notification rules may include: determining whether to publish the presence information in accordance with a status of the presentity.
[0050] Optionally, the content-related processing rules may include a maximum subscription times, and the presence information is allowed for subscription when the number of subscription is less than the maximum subscription times.
[0051] Optionally, the content-related processing rules may include: allowing a watcher to receive presence information when a receipt frequency and/or a receipt period of the watcher is within a scope.
[0052] Another embodiment of the present invention provides a presence server including a publication and notification processing component and a notification rules processing component. The publication and notification processing component is adapted to determine a watcher for receiving the presence information in accordance with the subscription relationship, to send to the notification rules processing component a query whether a presentity publishing the presence information has set notification rules, and to process the presence information in accordance with the content-related processing rules and a response returned from the notification rules processing component; and the notification rules processing component is adapted, upon receiving the query sent from the publication and notification processing component whether the presentity publishing the presence information has set notification rules, to determine whether the presentity has set the notification rules, and if yes, whether the notification rules are met in accordance with the notification rules, and to send the response to the publication and notification processing component.
[0053] Optionally, the notification rules may include: allowing presence information to be notified when notification time of the presence information is within a validity term and/or a prescribed publication period.
[0054] Optionally, the notification rules may include: allowing presence information to be notified when a receipt number of times of a watcher subscribing the presence information does not exceed a limit on number of times and/or a receipt frequency of the watcher does not exceed a transfer frequency.
[0055] Optionally, the notification rules may include: determining whether to publish the presence information in accordance with a status of the presentity.
[0056] Optionally, the content-related processing rules may include a maximum subscription times, and the presence information is allowed for subscription when the number of subscription is less than the maximum subscription times.
[0057] Optionally, the content-related processing rules may include: allowing a watcher to receive presence information when a receipt frequency and/or a receipt period of the watcher is within a set scope.
[0058] A further embodiment of the present invention provides a presence XDMS applicable to a system for notifying presence information, and the presence XDMS may include a reading unit and a storage unit. The reading unit is adapted to forward received external input data to the storage unit, and when receiving a data retrieval signal sent from an external component, read corresponding data in the storage unit in accordance with type of the signal, and output the data to the external component that has sent the data retrieval signal, the external input data comprises a notification rules; and the storage unit is adapted to receive and store the data input from the reading unit.
[0059] In the embodiments of the present invention, the resources of a presence server may be utilized more appropriately and the publication of presence information is enabled to be more rationalized and humanized. A user may determine whether to receive the published information and what published information to receive according to the actual requirement.
BRIEF DESCRIPTIONS OF THE DRAWINGS
[0060] FIG. 1 is a structural diagram of a system for notifying presence information in the prior art;
[0061] FIG. 2 is a structural diagram of a publication and notification processing component in the prior art;
[0062] FIG. 3 is a flow chart of a method for notifying presence information in the prior art;
[0063] FIG. 4 is a structural diagram of a system for notifying presence information according to an embodiment of the present invention;
[0064] FIG. 5 is a flow chart of a method for notifying and publishing according to an embodiment of the present invention;
[0065] FIG. 6 is a structural diagram of a publication and notification processing component according to an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0066] The embodiments of the present invention will be further described with reference to the drawings.
[0067] Referring to FIG. 4 , similar to the presence system in the prior art, an improved system for notifying presence information includes a presentity client or presentity application server, a presence server, a watcher client or watcher application and a presence XDMS. The difference lies in that a notification rules processing component is added in the presence server. In other words, the presence server includes a subscription processing component, a storage component, a publication and notification processing component and a notification rules processing component.
[0068] The subscription processing component receives a SUBSCRIBE message from the watcher client or watcher application server, retrieves a subscription authorization rules set by the corresponding presentity in the presence XDMS, and determines the subscription result for the watcher client or watcher application server in accordance with the subscription authorization rules, and if the subscription is allowed, stores the subscription relationship in the storage component.
[0069] The storage component stores the information on subscription relationship, publish content, etc.
[0070] The publication and notification processing component receives a publish request sent from the presentity client or presentity application server, and gets a certain subscriber (a watcher) from the storage component, and retrieves content-related processing rules and notification rules set by the presentity and the watcher from the presence XDMS, then sends a query to the notification rules processing component, processes the presence information in accordance with the content-related processing rules set by the presentity and the watcher and a response returned from the notification rules processing component, and notifies the watcher client or watcher application server of the processed (combined, composed, content-filtered, etc.) presence information.
[0071] The notification rules processing component receives the query sent from the publication and notification processing component whether the presentity has set a notification rules, then determines whether there is any notification rules set by the presentity, and if there is, determines in accordance with the notification rules whether a notification condition is met, and then returns a response to the publication and notification processing component.
[0072] The subscription processing component and the storage component in the presence server may be identical to those in the prior art, and therefore will not be described here.
[0073] The presence XDMS is adapted to store authorization rules (e.g. subscription authorization rules, content authorization rules, etc.) set by the presentity, and is also adapted to store notification rules set by the presentity. The presence XDMS includes a reading unit and a storage unit.
[0074] The reading unit is adapted to forward received external input data to the storage unit, and upon receiving a data retrieval signal sent from an external component, reads corresponding data in the storage unit in accordance with the type of this signal, and outputs the corresponding data to the external component that sends the data retrieval signal. The external input data includes the notification rules.
[0075] The storage unit is adapted to receive and store the data input from the reading unit.
[0076] In the system for presenting information, the presentity client or presentity application server and the watcher client or watcher application server are identical to those in the prior art, and therefore will not be described here.
[0077] Referring to FIG. 5 , a flow of a method for notifying presence information will be described hereinafter. Presentity A represents a presentity client or presentity application server, and watcher B represents a watcher client or watcher application server:
[0078] 1) The presentity A sets content-related processing rules and notification rules;
[0079] 2) The watcher B sends a subscription request to a presence server, to subscribe the presence information of the presentity A;
[0080] 3) The presence server processes in accordance with subscription authorization rules stored in a presence XDMS. If the subscription authorization is not passed, the subscription fails, otherwise, the presence server stores the subscription relationship;
[0081] The above content-related processing rules may include subscription authorization rules. For example, the presence information will not be allowed for publication unless the number of times that the presence information has been published is below a maximum number of times. The content-related processing rules may also include rules that the watcher is allowed to receive the presence information only when a receipt frequency or receipt period of the watcher is within a scope;
[0082] 4) The presentity A publishes presence information to the presence server;
[0083] 5) The presence server determines the watcher B in accordance with the subscription relationship, and determines whether the presentity A has set notification rules, and if there is notification rules, determines whether the watcher B meets the notification rules and continues to execute step 6), or if there is no notification rules, proceeds in accordance with the presence method in the prior art;
[0084] In this step, the process that the presence server determines whether the watcher B meets the notification rules includes:
[0085] (a) determining whether it is within the validity period, such as Oct. 1, 2005˜Sep. 1, 2005; if it is not within the validity period, blocking the notification of presence information to the subscriber, otherwise, determining in accordance with other rules;
[0086] (b) determining whether it is within a prescribed notification period, such as 8:00˜18:00 of each day; if it is not within the prescribed notification period, blocking the notification of presence information to the subscriber, otherwise, determining in accordance with other rules. For example, the presentity has set a prescribed notification period such as 8:00˜18:00 of each day, if the time the presence server receives publish information is 9:00, it meets the requirement of the rules;
[0087] (c) determining whether the number of times that the watcher B has received information exceeds an upper limit; if it exceeds the upper limit, blocking the notification of presence information to the subscriber, otherwise, determining in accordance with other rules. The presentity A may set a limit to the number of times that the watcher B receives information. For example, the total number of times is 1000 with 10 times for each day, then a counter may be set for the total number and the number for each day. Then, the counter for the total number is increased by one each time information is received, and the counter for each day counts from zero every day, and is increased by one each time information is received. Prior to sending a notification, it may be determined whether the current total number of times exceeds 1000 and whether the number of times for the current day exceeds 10, and if information transfer is allowed, both the total number and the number for the current day are increased by one. On the next day, the counter for each day is reset to zero; but the counter for the total number is not reset to zero;
[0088] (d) determining whether the receipt frequency that the watcher B receives information is above a set transfer frequency; if the receipt frequency is above the transfer frequency, blocking the notification of presence information to the subscriber, otherwise, determining in accordance with other rules. There may be two ways to set the transfer frequency: (1) once every ten minutes. For example, if starting from 8:00, between 8:00˜8:10, the presence server may choose to either process the most recently published information and notify the watcher of the processed information at the time of 8:10, or combine the presence information published several times within these ten minutes and publish the combined information to the watcher; (2) no more than ten pieces of information within one minute; in this case, once the publish information is received, the presence server processes the information and notifies the watcher of the processed information, and counts; the information beyond the limit of ten pieces will be dropped; The above notification rules for the presence server to determine whether the watcher B meets the notification rules may include one or more rules, and further the order of determinations may be set arbitrarily. When all the rules have been referred to, the process proceeds to step 6);
[0089] 6) When the watcher B meets the notification rules, the presence server performs processing for publication (including information composition, content authorization, event notification filtering, and the like, the content authorization an the event notification filtering are optional), and publishes the presence information to the watcher B. If the watcher B does not meet the notification rules, the presence server aborts the notification of presence information to the watcher B.
[0090] In one embodiment according to the present invention, the notification rules may be set by a user client in the presence XDMS or in the presence server. The notification rules processing component in the presence server may retrieve the rules from the presence XDMS or the presence server for further processing. The notification rules may be modified and set by the presentity client through the XCAP protocol in the XDMS, or may be modified and set in any other ways. For example, the presence server may provide the presentity with a WEB interface to view the notification rules set by the presentity, and allow the presentity to initially set or modify its notification rules via the WEB interface.
[0091] It shall be noted that in addition to the rules content mentioned in the above embodiments, the notification rules may also include other rules contents, such as determining whether to publish presence information in accordance with the status of the presentity.
[0092] Although in the above embodiment the notification rules processing component is located in the presence server and separated from the publication and notification processing component, the notification rules processing component with the same functions may be located in the publication and notification processing component in another embodiment. The structural diagram of this publication and notification processing component is as shown in FIG. 6 , the method for notifying presence information is similar to the above embodiment and the descriptions thereof will not be repeated here.
[0093] In an alternative embodiment, the watcher B may subscribe the presence information directly from the presentity A without setting subscription authorization rules. It may be determined flexibly where to store the subscription authorization rules, the subscription relationship, etc. For example, they may be stored in the presence server or in the presence XDMS.
[0094] It shall also be noted that the content-related processing rules and the notification rules are set and stored in the presence XDMS, and in another embodiment, they may be set and stored in the presence server. Moreover, the notification rules may also be included in the content-related processing rules.
[0095] In the present embodiment, both the watcher and the presentity may be presentity client or application server, and the application server may include a game server or a server with similar functions, and may also include an instance message server (e.g. an ICQ/MSN server) etc.
[0096] It shall further be noted that in the above flow, it may be determined that the notification rules are met if there is no limiting condition. Thus, there is no limit to the processing order of the procedure of determining the notification rules and publication (involving the processes of the presence information composition component, the content authorization rules checking component, the watcher filtering component, the partial notification processing component and the presence information publish component). The objects of the present invention may be attained no matter how the order would be. The various conditions may be stored and processed in the form of database.
[0097] It shall be noted that those skilled in the art may easily implement each operational step and the setting of each rules or policy concerned in the embodiments of the present invention by means of programming techniques in the prior art.
[0098] Some application embodiments will be described hereinafter.
[0099] 1. A traffic information service may provide presence information on road conditions for all weather, 24 hours a day, but with a charge. The service may be free for a new user with some limiting conditions. For example:
[0100] (1) The presence information may be received for free for 1000 times.
[0101] (2) The period for free receipt may be limited to 8:00˜12:00 each morning.
[0102] (3) The service may be tried out twice for free. In other words, a user may subscribe and try the service again when a limiting condition for free usage expires, but has to pay when the limiting condition for free usage expires again.
[0103] A new user with a free subscription may receive the presence information during only a limited period each morning, and the service will become invalid after 1000 times of receipt. The new user has to subscribe again for another free tryout. However, the service can no longer be tried out if it becomes invalid again unless the user pays.
[0104] In this embodiment, the traffic information service server is a presentity, and the user is a watcher.
[0105] The specific implementation of this embodiment will be described hereinafter.
[0106] The notification rules in this embodiment may be included in the content authorization rules, and in another embodiment, may be a rule file newly created instead of being included in the content authorization rules.
[0107] The subscription authorization rules (with a principle of precise matching, i.e., a general field will not be matched if a specific user has been matched):
Limit on subscription Watcher ID Result number of times zhangsan@future.com BLOCK 2 *@163.com ALLOW 2
[0108] the content authorization rules may be:
Information on number of times Watcher ID road conditions for receipt Receipt period *@163.com ALLOW 1000 8:00˜12:00
[0109] When the watcher ID has a field “@163.com”, the watcher may be allowed for subscription twice (the limit on subscription number of times is decreased by one automatically when the subscription succeeds once, and the subscription is disallowed when the limit on subscription number of times reaches zero). If there is no limiting condition set on the limit on subscription number of times, the default number of times of the presence server may be one, or alternatively, it may be default that there is no limit on the subscription number of times, and the default number of times may be set by the presence server. Here, the subscription generally refers to an initial subscription of a watcher, not including the number of times for refreshing the subscription. If a subscription without timely refresh has expired, when re-subscribing, the subscription number of times is increased by one. In fact, it may be sufficient to limit the amount of information obtained by the watcher through only the condition of the receipt number of times, in that the watcher may have to re-subscribe due to various reasons, such as instability of a network or client, powering on or off, etc., and thus, the limit on the subscription number of times will not be appropriate. For example, when the traffic information service publishes information at the time of 9:00 am., the ID “@163.com” may be matched, and the result may be allowed for subscribing information on road conditions, and the notification rules may specify that the watcher with a matched ID may be allowed to receive the information for 1000 times, and the receipt period may be 8:00˜12:00 each day. The presence server determines whether the number of times the watcher has received the information is no more than 1000 and whether the time of 9:00 is within the scope of 8:00˜12:00. If that number of times is no more than 1000, and that time is within the that scope, the result of the notification rules may be ALLOW, and the presence server will send the information on road conditions to the watcher, and the number of times that the watcher has received the information will be increased by one.
[0110] The above notification rules may be described as follows in the XML format.
<conditions> <identity> <domain domain=“163.com”/> </identity> <period> <from>T08:00:00.000+08:00</from> <until>T12:00:00.000+08:00</until> </period> <subscribe-counts limit=“2”>1</subscribe-counts> <receive-counts limit=“1000”>88</receive-counts> </conditions>
[0111] The limit on period is designated in the element <period> including a starting time <from> and an ending time <until> of the period, and the format of time includes year, month, date, minute, second, time zone, etc. If the presence server detects only the absence of year information, it indicates that a yearly period has been set. If the presence server detects the absence of year and month information, it indicates that a monthly period has been set. If the presence server detects the absence of year, month and date information, it indicates that a dayly period has been set, and so on. The starting and ending times may also be used as attributes of the element <period>. The limit on subscription number of times is designated in the element <subscribe-counts>, in which the limit attribute indicates an allowed subscription number of times, and the value of the element <subscribe-counts> indicates the number of times that the subscription has been performed. The same may apply to the element <receive-counts> which indicates the limit on receipt number of times.
[0112] When the actual subscription number of times and receipt number of times change, the presence server will update the values of the elements <subscribe-counts> and <receive-counts>. If the actual subscription number of times and receipt number of times are recorded in an authorization rules file, the presence server will further modify that authorization rules file stored in the XDMS in synchronization with the change of the values of the elements. Preferably, the actual subscription number of times and receipt number of times may be stored separately from the limits on number of times. In other words, the limit on subscription number of times and the limit on receipt number of times may be stored in the authorization rules file, which may be retrieved by the presence server from the presence XDMS, while the actual subscription number of times and receipt number of times may be stored locally into the presence server instead of the presence XDMS. The presence server may create for each watcher user a record of subscription/receipt number of times, and update the record when the number of times changes. Thus, the authorization rules file will not have to store a large number of records resulted from the different actual subscription/receipt number of times of respective watchers, and it will be unnecessary to frequently synchronize the authorization rules buffered in the presence server with the authorization rules file stored in the presence XDMS. As in the following authorization rules file, the presentity may set the same limit on number of times for all watchers or the watchers within a certain domain:
<conditions> <identity> <domain domain=“163.com”/> </identity> <subscribe-counts limit=“2”/> <receive-counts limit=“1000”/> </conditions>
[0113] The presence server records the actual numbers of times for different watchers, for example:
subscription receipt number of number of Watcher ID Presentity ID times times User1@163.com traffic@service.com 1 88 User2@163.com trafFic@service.com 2 101
[0114] Upon detecting the actual receipt number of times of a watcher with a matched ID exceeds the limit on receipt number of times designated in the authorization rules, the presence server blocks the transfer of the corresponding presence information.
[0115] 2. User A may wish to publish his own presence information to his collogues during working period (8:00˜18:30 each day), and not to publish his presence information to his collogues during other periods.
[0116] The user may set a limit, with respect to *@163.com, to the period that a watcher obtains the presence information, while setting no limit to the receipt number of times and the subscription number of times.
[0117] The subscription authorization rules (with the principle of precise matching, i.e., a general field will not be matched if a specific user has been matched):
Watcher ID Result Priority zhangsan@163.com BLOCK 1 *@163.com ALLOW 2
[0118] The content authorization rules:
A number of Location Game times for Receipt Watcher ID information information receipt period *@163.com ALLOW BLOCK No limit 8:00˜18:30
[0119] When the ID of a watcher has the field “@163.com” which is not “zhangsan@163.com”, the watcher may be allowed for subscription. When user A publishes presence information at the time of 9:00, the presence server determines that there is no limit on receipt number of times in the notification rules, and the publication period is 8:00˜18:30, the result is ALLOW, and the content is ALLOW for receipt of location information, but is BLOCK for receipt of game information. The presence server distributes the location information to all watchers with the ID “@163.com” except “zhangsan@163.com”, and thereafter the receipt numbers of times of respective watchers will be increased by one respectively.
[0120] 3. A presentity may wish not to publish his presence information to a watcher when the presentity is in a special status. For example, a boss has subscribed the presence information related to the location and status of an employee. When playing a game, the presentity (the employee) changes his presence status to “In Game”, and he has set in advance not to send the presence information on the location and the status “In Game” to the boss when the presentity is in such a status. As a result, though the presentity transmits the information to the presence server, the presence server will not send the presence information to the subscriber, i.e. the boss, in accordance with the setting of the presentity.
[0121] Notification Rules:
Watchers allowed for Watchers disallowed for Status or location Action notification notification In Game Limit the group to be notified *@game.com boss@163.com of presence information At Work Do not send work-related *@163.com *@game.com information to a game team In Travel Do not notify company colleagues zhangsan@future.com *@163.com of location information lisi@sina.com
[0122] As obvious from the above notification rules, when the employee (presentity) is in the status “In Game”, the presence information is allowed to be notified to *@game.com, but disallowed to be notified to boss@163.com. When the employee (presentity) is in the status “At Work”, the presence information is allowed to be notified to *@163.com, but disallowed to be notified to *@game.com. When the employee (presentity) is in the status “In Travel”, the presence information is allowed to be notified to zhangsan@future.com and lisi@sina.com, but disallowed to be notified to *@163.com.
[0123] In a preferred embodiment according to the present invention, the notification rules may include determining the receipt statuses of all watchers and performing corresponding processes as follows: the notification rules processing component determines the receipt statuses of all watchers. For example, in accordance with whether a watcher is online. If each of the watchers is in a status incapable of receiving the presence information, the publication and notification processing component in the presence server will notify the presence client or application server not to publish presence information during this period. When there is a watcher in a status capable of information receipt, the presence server may notify the presentity to proceed with publication.
[0124] While the embodiments in which a presentity sets notification rules have been described as above, a watcher may also set receipt rules. The receipt rules may be set in the presence XDMS or the presence server, or may be set through a SUBSCRIBE message upon subscription. The receipt rules may be stored in the presence server or the presence XDMS. The watcher may set validity term for subscription, subscription period, receipt number of times and a receipt frequency in the receipt rules. A corresponding receipt rules processing component may be employed to determine in the same way as the notification rules whether it is within the validity term for subscription, the subscription period, or the receipt number of times, and to determine whether the condition is met in accordance with the receipt frequency. Moreover, the presence server may process in accordance with the receipt frequency, the receipt period and the receipt status, and then notify the presentity client to control the rate/frequency and the period for publication information. In the system, the notification rules set by the presentity may be processed first, and then the receipt rules set by the watcher may be processed. Subsequently, the publication and notification processing component processes publish information in accordance with the content related processing rules set by the presentity and the watcher, and transfers the processed information to the watcher. The processing flow and means are similar to those used to process the rules set by the presentity as described above, the descriptions thereof will not be repeated here. Those skilled in the art may implement the solutions provided according the embodiments of the present invention by means of various technologies in the prior art without any inventive effort.
[0125] While some preferred embodiments of the present invention have been described above, the scope of the present invention shall not be limited thereto. Those skilled in the art may make various changes and modifications without departing the scope of the present invention. It is thus intended that all these changes and modifications shall fall within the scope of the present invention as defined in the appended claims. | A method for notifying presence information is disclosed. The method includes: setting, by a presentity, notification rules; when receiving the presence information sent from a presentity client or presentity application server, transferring, by a presence server, to a watcher client or watcher application server the presence information that is conformable to the notification rules as well as content related processing rules set by a watcher and the presentity. The present invention further discloses a system for notifying presence information, a presence server and a presence XDMS. Compared with the prior art, the present invention takes advantages of resources of a presence server more appropriately and enables the publication of presence information to be more rationalized and humanized. Thus a user may determine whether to receive the published information and what published information to receive according to the actual requirement. | 7 |
This application is a continuation of U.S. patent application Ser. No. 08/166,590, filed on Dec. 14, 1993 now abandoned.
FIELD OF THE INVENTION
The invention relates generally to a support bearing and more particularly to a liquid-filled support bearing having a hydraulic damping device and two fittings The support bearing may be used, for example, as a support for the engine of an automobile.
BACKGROUND OF THE INVENTION
Such a bearing is disclosed by German Unexamined Patent Application 38 20 805. The two fittings are made up of an inner and an outer cylinder, there being essentially three hollow spaces provided on both sides of the inner cylinder in the direction in which vibrations are introduced. One of the hollow spaces, which is adjacent to the inner cylinder, is liquid-filled. It is subdivided into a working chamber and a compensation chamber by means of a partition wall, which consists of inflexible material and is suspended in a way that allows it to vibrate. The working chamber and the compensation chamber are in fluid communication with one another, the working chamber being bounded by the elastic spring element and the compensation chamber by a bellows-type membrane. It is worth noting, however, that the bearing consists of a plurality of individual parts and, as a result, is not very satisfactory from a standpoint of economics and production engineering. Moreover, the massive form of the partition wall makes it problematic to isolate higher-frequency vibrations.
SUMMARY AND ADVANTAGES OF THE INVENTION
An object of the invention is to provide a bearing so as to produce a considerably simplified structure and better working properties with respect to isolating or damping vibrations lying within at least two frequency ranges.
Another object of the invention is to provide a bearing which is able to be adapted quite easily to the particular conditions of the application case.
The present invention therefore provides a liquid-filled bearing which provides damping of vibrations caused by movement in a moving direction comprising: an inner fitting; an outer fitting surrounding the inner fitting and spaced apart from the inner fitting, at least one fitting having a gap extending essentially parallel to the moving direction; an elastic spring element of elastomer material connecting the inner fitting and the outer fitting so as to form at least two chambers, the chambers being filled with liquid, the gap being open to at least one chamber; and at least one movable partition wall disposed in said gap in a rolling diaphragm-type profile.
Therefore, it is provided for at least one fitting to have a gap extending essentially parallel to the direction of movement and open in the direction of at least one of the two chambers and for the partition wall to consist of elastomer material and to join together the surfaces defining the gap in the area of the wall extremities as the result of a rolling-diaphragm-type profile. The profile preferably has an S-shaped design.
The advantageous refinement of the partition wall makes it possible for this wall to be adapted quite favorably to the particular conditions of the application case. The length of the gap can be selected essentially independent of the shape of the fittings and extend virtually within the entire extent of the outer fitting. Because of its simple structure, the bearing can be produced inexpensively and adapted to any application case at all, for example, simply by exchanging the fitting that is provided with the gap. Because of the way the partition wall is arranged inside the gap, it is only able to move at essentially right angles to the moving direction of the introduced vibrations. In conjunction with the S-shaped profile and the fixing to the surfaces defining the gap, this leads to an especially low-noise operation of the bearing. When higher-frequency, small-amplitude vibrations are introduced, the partition wall vibrates freely between the adjacent surfaces, without coming in contact with them in the area between their extremities. When low-frequency, large-amplitude vibrations are damped, the partition wall comes to rest against one of the surfaces, section by section and also gradually, in dependence upon which of the two chambers has the comparatively higher pressure. To minimize impact noises, the partition wall can be at least partially contoured in the area of its top surfaces. In the same way, the adjacent surfaces can be additionally or alternatively contoured. This effect is enhanced further, because the surfaces defining the gap preferably do not run parallel to the top surface of the partition wall. This refinement makes it possible to reliably rule out any cavitation in the vicinity of the gap. In accordance with one advantageous refinement, at least one limit stop can be configured next to the partition wall to restrict deflection movements.
According to one advantageous refinement, the partition wall and the elastic spring element can be designed to blend into one another in one piece. This refinement further simplifies the manufacturing of the bearing.
With respect to attaining a further damping maximum and, thus, broader damping, two gaps and two partition walls can be provided within the bearing. The two partition walls are preferably distinguished from one another by differing inertial masses and/or spring constants. For example, one of the partition walls can be designed to be comparatively thin-walled with respect to insulating higher-frequency vibrations and, as a result, have a smaller inertial mass. Because the wall would then be able to be easily shifted back and forth when high-frequency vibrations are introduced, such relative movements executed by this separation wall can be compensated. When such vibrations are introduced, virtually no pressure changes occur within the adjacent chambers, so that the introduced vibrations cannot be transmitted to the attached component part.
To damp low-frequency vibrations, the two chambers can be in fluid communication with one another through a restrictor duct that functions as the damping device. The length and the cross-section of the restrictor duct is preferably adjusted so as to allow vibrations within the frequency range of 5 to 15 Hz to be damped as the result of a resonant vibration of the liquid column inside the damping duct.
The simple design of the bearing can be enhanced by having the restrictor duct be delimited by an outer plate bearing the rubber member and by an outer pot surrounding the outer plate. In this case, the outer fitting is designed as an outer pot.
The following explanations pertain to the functioning of the bearing:
When low-frequency, large-amplitude vibrations are introduced in the range of 5 to 15 Hz, the partition wall comes to rest gradually and section by section, with its top surface, which is arranged in the lower-pressure chamber, against the adjacent surface of the fitting defining the gap. When the partition wall comes to rest against the surface, a hardening of the bearing sets in. The low-frequency vibrations are damped by way of the restrictor duct interconnecting the two liquid-filled chambers. Comparatively higher-frequency vibrations, for example in the range of 15 to 100 Hz, are insulated as a result of the capability of the partition wall to move freely back and forth between the stop faces and as a result of the opposite-phase vibrations of the liquid components in the gap area. These effects improve for example the idling performance of motor vehicles when the bearing supports an automobile engine. When at least one additional gap with a partition wall arranged therein is employed, additional damping maxima can be achieved. These can be adapted quite favorably to the particular conditions of the application case due to the mobility of the partition wall and the refinement of the gap.
A stop buffer that projects into at least one chamber in the moving direction of the vibrations can be provided on at least one of the fittings, the stop buffer being preferably provided with a protective rubber layer that is designed in one piece with the elastic spring element. With respect to an improved service life, it is possible for the protective rubber layer to be provided in the area of its stop faces with a comparatively inflexibly designed reinforcement. Extreme deflections, which are restricted by the stop buffer, do not cause the elastic spring element to be overstretched. The protective rubber layer between the stop faces of the two fittings can be provided, if needed, with at least one depression, in order to effect, in this manner, a limit-position damping with further minimization of generated noise.
The moving direction and the gap preferably form an angle of less than 20°. The rolling-diaphragm-type partition wall and its arrangement parallel to the moving direction of the introduced vibrations prevent instances of fluid vorticity inside the bearing as in the case of limit-stop contact between the partition wall and the adjacent surfaces. The bearing is sealed off in a fluid-tight manner at its front extremities from the environment, and delimited by moldable, rubber-elastic front walls, which are likewise designed in one piece with the elastic spring element. The front walls are preferably shaped so as not to permit any significant tensile stresses, even when the inner fitting experiences extreme deflections relative to the outer fitting. As a result, the advantageous working properties can be retained over a long service life.
BRIEF DESCRIPTION OF THE DRAWINGS
The subject matter of the invention will be described further with reference to the following drawings:
FIG. 1 shows a support bearing in a cross-sectional representation;
FIG. 2 shows a longitudinal cross-section through a support bearing similar in most respects to the bearing of FIG. 1 and approximately in accordance with the line of intersection A--A;
FIG. 3 shows a cross-sectional representation of another embodiment of a support bearing, similar to the exemplified embodiment of FIG. 1, in which two gaps, each having a partition wall, are provided inside the inner fitting;
FIG. 4 shows a longitudinal cross-section through a support bearing similar in most respects to the bearing of FIG. 3 and approximately in accordance with the line of intersection A--A;
FIG. 5 shows a third exemplified embodiment, in which the partition wall is only partially arranged inside the surfaces delimiting the gap;
FIG. 6 shows the bearing of FIG. 5 in a representation in longitudinal section approximately along the line D--D;
FIG. 7 shows the bearing of FIG. 5 in a cut-off representation along the line F--F;
FIG. 8 shows a further exemplified embodiment, similar to the embodiment of FIG. 5 in which the inner fitting has a modified stop face;
FIG. 9 shows the bearing of FIGS. 8 in a representation in longitudinal section along the line G--G.
DETAILED DESCRIPTION
The bearings 1 depicted in FIGS. 1-9 comprise two fittings 3, 4, which surround one another and are braced against one another by means of an elastic spring element 5 of elastomer material. The fittings 3, 4 consist in these exemplified embodiments of a metallic material, whereby in each of the exemplified embodiments, the inner fitting 3 has a longitudinal bore hole 22 and at least one gap 12, a partition wall 11 being arranged inside the gap 12. In these exemplified embodiments, the partition wall 11 is designed to blend in one piece with the elastic spring element 5 and also with a protective rubber layer 21 of a stop buffer 20 of inner fitting 3. The partition wall 11 connects with the elastic spring element at extremities 15, 16. The inner fitting 3 has limit stops 9, 10 configured next to the partition wall to restrict deflection movements of the partition wall 11. Two liquid-filled chambers 7, 8 are in fluid communication with one another by way of a restrictor duct 17, which is designed as a damping device 2. The elastic spring element 5 is affixed to an outer plate 18, which is designed as an end-window tube and is made of a metallic material. The outer plate 18 is supported so as to render it immovable and liquid-tight in the outer fitting 4. The inner and the outer fittings 3, 4 are designed to be assembled with parts of a machine, i.e., with the chassis and the body of a motor vehicle. The elastic spring element 5 is joined, on the one hand, by means of direct prevulcanization, to the inner fitting 3 and, on the other hand, to the outer plate 18. The outer plate 18 is surrounded by outer pot 19 of the outer fitting 4. In a moving direction 6 of the introduced vibrations, the inner fitting 3 is provided on both sides of longitudinal bore hole 22 with stop buffers 20, which project in the direction of the chambers 7, 8 and are each provided with protective layer 21 of rubber elastic material, which is designed in one piece with the elastic spring element 5. When vibrations of a larger amplitude are introduced which require damping, the partition walls 11 of the bearings depicted here come at least partially in contact with the surfaces 13, 14 delimiting the gap 12 and, as a result, effect a hardening of the bearing. When the partition walls 11 come at least partially to rest against the surfaces 13, 14, liquid components are pressed through the restrictor duct 17 into that chamber 7, 8 in which the comparatively lower pressure prevails. This results in an excellent damping effect. This damping effect can be based on the utilization of the restrictor or on absorption effects, in dependence upon the particular formation of the damping opening. The prerequisites for making such adjustments are known to one skilled in the art and are not a subject of the present invention.
When the two fittings 3, 4 experience extreme deflections in relation to one another, the stop buffers 20 can strike with their rubber-elastic protective layer 21 against the adjacent inner side of the outer fitting 4. The elastic flexibility of the protective layer 21 largely prevents unwanted impact noises from occurring.
In FIG. 1, the partition wall 11 only extends within the gap 12, which is delimited by the surfaces 13, 14 of the inner fitting. An advantage here is that undesired, substantial deformations of the partition wall 11 are reliably prevented, even when impact stresses and resulting pressure peaks occur inside the chambers 7, 8. In dependence upon the particular conditions of the application case, one can provide for a reinforcement inside the partition wall. This is generally superfluous, however, in the case of a refinement in accordance with FIG. 1.
FIG. 2 shows a longitudinal section through a bearing 1 essentially similar to that of FIG. 1 along the section A--A. As proceeds from this drawing, the restrictor duct 17 has an annular shape and extends along the outer periphery of the bearing 1.
In FIG. 3, a bearing 1 is shown whose design is similar to that of the bearing 1 of FIG. 1. To attain a further damping maximum, however, an additional gap 12.2 is provided in this exemplified embodiment. This gap 12.2 is likewise arranged inside the inner fitting 3, the two gaps 12.1, 12.2 having essentially a symmetrical design. The function of the partition wall 11.1 inside the gap 12.1 corresponds to the function of the two parts of FIG. 1, while a second partition wall 11.2 inside the second gap 12.2 exhibits a relatively increased material strength and, as a result, a greater inertial mass and spring constant. To damp low-frequency vibrations in the range of, for example, 10 Hz, both of the two partition walls 11.1, 11.2 are positioned against one surface each of the gaps 12,1, 12.2, in dependence upon the pressure difference prevailing between the two chambers 7, 8.
Fluid is exchanged between the two neighboring chambers 7,8 through the restrictor duct 17. This refinement makes it possible for comparatively higher-frequency vibrations within a broad frequency range to be damped/insulated.
In FIG. 4, a bearing 1 essentially similar to that of FIG. 3 is depicted in a longitudinal section approximately along the line B--B.
FIG. 5 illustrates another exemplified embodiment of a bearing, in which the partition wall 11 is able to be positioned against the surfaces 13, 14 of the gap 12 in one partial section only. The advantage of the bearing according to the invention can be seen in its universal applicability. When the external dimensions remain unchanged, the working properties can be advantageously influenced by varying the refinement of the inner fitting 3 with the gap 12 provided therein and the partition wall 11. In this exemplified embodiment, the partition wall 11 can be reinforced, particularly in the transition region where it emerges from the gap 12 of the inner fitting 3, to avoid the unacceptably large deformations that can occur when it is subjected to pressure peaks. Diverging from this refinement, the shape of the membrane can be varied to such an extent and, for example, shortened in length, so that a nearly U-shaped profile will result from the essentially S-shaped profile. Besides a change in the length, deviations in the flexural stiffness of the partition wall 11 can advantageously influence the working properties of the bearing.
In FIG. 6, the bearing depicted in FIG. 5 is shown in a representation in longitudinal section along the line of intersection D--D.
FIG. 7 depicts the bearing of FIG. 5 along the section F--F. One can recognize the one-piece inner fitting with its gap, and the partition wall arranged inside the gap.
FIG. 8 depicts a fourth exemplified embodiment of the bearing according to the invention, in which the inner fitting 3 exhibits the duct-type gap 12, which is sealed off by the partition wall 11 in the direction of the chamber 7. The surfaces 13, 14, which are provided as stop faces, extend on both sides along the essentially U-shaped partition wall 11 and are allocated to adjoin this wall with clearance. In this exemplified embodiment, the surfaces 13, 14 and the partition wall 11 are profiled over their entire surface area to reliably rule out impact noises and cavitation during operation of the bearing.
FIG. 9 illustrates the bearing of FIG. 8 along the section G--G.
The bearings 1 according to the exemplified embodiments 1 through 9 are each shown in a non-installed state that is conditional upon manufacturing. In relationship to the outer fitting 4, the longitudinal bore hole 22 exhibits an eccentricity, which can be reduced or completely eliminated after installation through the application of a static preload.
While the present invention has been disclosed with respect to the above-described embodiments, it is contemplated that other embodiments may fall within the scope of the present invention. | A liquid-filled bearing having a hydraulic damping device and two fittings which surround one another and are joined by an elastic spring element of elastomer material, there being at least one movable partition wall disposed between two liquid-filled chambers. At least one of the fittings has a gap extending essentially parallel to a moving direction and open in the direction of at least one of the two chambers. The partition wall consists of elastomer material and joins together surfaces defining the gap as the result of a rolling-diaphragm-type profile. | 1 |
BACKGROUND OF THE INVENTION
The present application for a Patent of Invention relates, as indicated in its title, to "AN IMPROVED ANTI-PINCHING SYSTEM BASED ON MODIFICATION OF THE LIGHT CONDUCTIVITY OF AN OPTICAL FIBRE FOR AUTOMATIC CAR WINDOWS", whose new characteristics of construction, form and design fulfil with maximum reliability and efficacy the purpose for which it has specifically been designed.
The invention relates more specifically to the design of a new anti-pinching system using a light transmission means to detect obstacles between the perimeter of the car window and the frame of the door and of said window.
A plurality of systems exist on the market, and may therefore be regarded as prior art, which are capable of detecting an obstacle when a car window ascends in its frame in response to pressure exerted by the user on the window control button.
Said systems which may regarded as prior art may be divided into two broad groups, direct systems and indirect systems. The first thereof consist of sensors which, owing to their sensitivity, permit direct detection of the obstacle and send the appropriate signal to the electric motor whose role it is to actuate the various components involved in raising the window in such a way that the latter is stopped and its operation is reversed, such that it descends.
The indirect systems act in the normal manner on the motor and analyse the operation thereof in such a way that, when the window encounters an obstacle, a variation is produced in the current circulating through the electric motor or a modification is produced in the speed of rotation thereof, which is detected by the appropriate sensors incorporated in the electric motor. That is to say, it is through this variation in current or speed that the system detects the presence of an obstacle between the window and its frame, causing the motor to stop and reverse its direction of rotation.
Although the above systems represent considerable progress with respect to early arrangements which did not provide said anti-pinching and obstacle-detection systems, they exhibit severe limitations since they are subject to frequent breakdowns and in some cases they interpret modifications in the environment in which the window is displaced as obstacles, for example hardening of the guideways or the rubber seals disposed in the door frame in many cases causes an increase in the resistance encountered by the window as it ascends in the frame, which the sensors interpret as the unexpected presence of obstacles, such that they stop the motor and reverse its rotation, obliging the user to return to the dealer so that the problem can be solved by reprogramming of the various systems so as to prevent said disadvantages.
On another technical plane, the above-described systems are in many cases incapable of sensing pinching at the sides, that is to say not only pinching which occurs between the upper part or edge of the window and the frame but also pinching which occurs between the side edges of the window and the side frames thereof, which is something which may happen with the rear windows in many car models and may cause serious injury to persons but cannot be detected by the above-described systems owing to the limitations thereof. This situation has been amply described in publications and journals relating to the industry.
The gravity of the above-described situations has caused even the authorities of the European Union to publish appropriate standards to ensure that the force with which the automatic windows are raised does not exceed critical values since, if this is not the case, such windows may cause very serious injuries to fingers, arms, the neck and other parts of the body which may become trapped between the upper or side edges of the window and those of the door frames or structures covering the latter.
DESCRIPTION OF THE INVENTION
The subject matter of the proposed invention is the design of an anti-pinching system for automatic car windows, which is intended to be capable of overcoming the above disadvantages in that it is capable of detecting obstacles directly by means of a light sensor disposed along the entire length of the window frame, the operation of which light sensor is based on the arrangement of an optical fibre conductor around the entire perimeter of said frame.
Said optical fibre conductor acts as a sensor and may be integrated into a special covering or directly into the covering of the frame, it being possible in some cases even to reduce the cost of the construction of said covering by incorporating that belonging to the insulating means with that belonging to the sensor means.
Tests carried out using this new anti-pinching system demonstrate that when the window to be raised in the door frame by suitable means encounters an obstacle, pressure is exerted on the covering and the proposed sensor in such a way that the latter reduces the amount of light it transmits, this reduction being analysed by the appropriate electronic systems provided with sufficient memory for comparing a normal light transmission value with a modified value, this comparison being used to interpret that said variation is caused by an obstacle encountered during raising of said window and the electric motor which actuates raising of said window then being commanded to stop, after which rotation of said motor is reversed, resulting in lowering of the window.
The proposed system combines great simplicity with low cost, by using commercially available components which do not therefore have to be newly designed, and with great ease of manufacture, since it may either be integrated into a special covering or, if necessary, be integrated into any of the surfaces of the covering of the door frame or the structure thereof.
The field and laboratory trials carried out with said system have demonstrated that higher sensitivity values may be obtained for the optical fibre conductor, that is to say a greater improvement of the system with respect to obstacles, by arranging the optical fibre conductor in loops, for which it is necessary to redesign the system in such a way that it includes both a rubber profile, which permits arrangement of said optical fibre in loops, and a new system of sensors which make it possible for the reference value not to have to be stored prior to operation of the system.
The proposed rubber profile, which is located inside the window frame and which is installed inside the seal located in the window frame, is designed in such a way that it comprises a series of incisions which permit arrangement of the optical fibre in undulating form, in such a way that, in said arrangement, said optical fibre protrudes therefrom, and in this way the angle of refraction in the case of deformation increases in magnitude and therefore increases the sensitivity of the system when the latter detects an obstacle, the upper edge of the window deforming said loops.
The incisions formed in the profile for passage of the optical fibre conductor and the arrangement thereof in looped form make it possible that, once positioning has been effected inside by suitable means, they are covered with adhesives or welded to keep covered the areas protected by the sealing profile, in such a way that all this permits wholly automated production.
The above-described profile is included inside the general seal which covers the whole window frame and which is situated at the upper part of the door.
In addition to the different arrangement of the optical fibre described above, another aim of the present invention is to modify the system for detecting obstacles so that it changes the reference value, that is to say the 30 millisecond value relating to the absence of obstacles, prior to raising the window, that is to say at the same moment in which the user presses the button to close the open window the improved system emits a signal for detecting the optical fibre transmission value at that moment, without any type of obstacle being present and before the window even starts its upward movement.
When the window, upon ascent, encounters an obstacle, the latter is pressed by the upward force thereof against the profile and the frame seal, which, in the system proposed in the main patent, changes the light conductivity value, and the sensor detects from said modification and reduction in transmission that an obstacle is present and causes the motor to stop and reverse its direction of rotation in such a way that the window descends and releases the obstacle from the upper edge of the window and the window frame.
By providing an instantaneous value which is not previously stored, the modification in the system for detecting the reference value thus allows the improved anti-pinching system to which the present invention relates to be independent of the variations in voltage which may occur in the car, that is to say when, for whatever reason, the car finds itself without power, whether because an electric circuit has been cut or because the battery is flat or for any other reason, it is not necessary, as happens with anti-pinching systems constituting the prior art, to reprogram the anti-pinching system and re-store the reference values so that the system may operate.
Therefore, given that in the systems which constitute the prior art said reference value differs depending on the model of car since different models exhibit differences with respect to the motor, the window length, the weight, the length of the seals and amount of friction, said improved anti-pinching system may be used in all types of cars and doors, whatever their structure, configuration and length, the weight of the windows and any other variant which a change of car model entails.
The incisions formed in the profile for passage of the optical fibre conductor and the arrangement thereof in looped form allow that, once said conductor is positioned therein by suitable means, the incisions are covered with adhesives or welded to keep covered the areas protected by the profile, in such a way that all this permits wholly automated production.
The above-described system with the improvements proposed in the present invention will be used to prevent pinching in doors, the bonnet and the boot, as well as in sunroofs.
Other details and characteristics of the invention will become clear from a reading of the description given below, which refers to the drawings accompanying this specification and in which the details referred to are shown schematically. These details are given by way of example, referring to one possible practical embodiment which is not limited to those details described here; therefore, this description should be regarded as an illustration, not limiting in any way.
BRIEF DESCRIPTION OF THE DRAWINGS
There follows a detailed list of the various elements cited in the present invention, (10) door, (11) inner side, (12) frame, (13) frame covering, (14) sensor, (15) sensor covering, (16) electric motor, (19) relay, (20) meter, (21) window, (22) cable, (23) guideway, (24) support, (25) sensor, (26) profile, (27) incisions, (28) mouth, (29) passageway, (30) cavity, (31) optical fibre, (32) end, (33) end, (34) loops.
FIG. 1 is a schematic front elevational view of a car door (10) viewed from the inside, in which the conventional components are arranged which permit raising and lowering of a window (21).
FIG. 2 is a partially cross-sectional elevational view of a frame (12) of a door (10), in which is located the proposed system.
FIG. 3 is a front elevational view of the sensor (25) formed by the profile (26) and the optical fibre conductor (31), forming a series of loops (34).
FIG. 4 is an upper plan view of the profile (26) with the proposed arrangement.
DESCRIPTION OF THE DRAWINGS
In one of the embodiments which may be regarded as prior art and which may be seen in FIG. 1, a door (10) takes the form of a sheet which has been duly machined into shape and is provided at its upper part with an appropriate frame (12) which, as may be seen in FIG. 2, is covered on the inside with a covering (13) which may become attached to a conventional window when the latter is raised, in such a way that when pressure is exerted on the upper part of said covering (13) a perfect seal is produced between the outer part and the inner part of the car.
FIG. 1 also shows the various components which are conventionally used for raising said window (21), such as an electric motor (16) which is supplied with power by a power source, not shown in the Figures, via a cable (22) and a guideway or guideways (23) which allow(s) vertical displacement of a support (24) located at the lower part of the window (21) and which, by means of the above-described components together with others of electrical nature, such as a relay (19) and a meter (20), form a system for detecting and reversing the movement of said window (21) in the frame (12) of the door (10).
FIG. 2 shows (13) the covering of the frame (12)-(13) in turn incorporates another covering (15), which has the sensor (14) incorporated within it.
The sensor (14) takes the form of an optical fibre conductor (31), which extends over the whole length of the frame (12) or part thereof.
Operation of the system is as follows: when the window is raised and lowered by means of the above-described components without any problems, there passes through the inside of the conductor (31) a quantity of light determined in accordance with the characteristics of the system and the particular characteristics of the optical fibre conductor, which is detected continuously by an electronic system not shown in the Figures.
When the window encounters any type of obstacle at its upper or side edges and said obstacle is pressed by the vertical ascending action of the window (21) against the covering (13) of the frame (12), the covering (15) of the sensor (14) receives pressure which is transmitted in turn to said conductor (31), consequently restricting and reducing the conduction and quantity of light, which is determined and detected by suitable electronic means programmed to carry out periodic checks such that any variation in the conduction of light will be interpreted to denote the presence of an obstacle.
By means of these suitable programming means, any variation in the conduction of light in the conductor (31) may be interpreted as a modification in the environmental conditions, that is to say any damage to the covering (13) or (15) caused by external means, aging or by poorly effected repairs to the door (10) of the car.
Embodiments may be considered equivalent which introduce the presence of an optical fibre conductor (31) not over the entirety of the length of the frame (12) but only over part thereof, better to suit the configuration and characteristics of said frame and car door (10).
An embodiment of the proposed system is one in which the covering of the door frame in turn incorporates another covering, the appropriate sensor being arranged therein, which sensor takes the form of an optical fibre conductor in wholly lengthwise arrangement, the length of said conductor covering all or part of the length of the window frame.
Said arrangement has been improved by the subject matter of the present, in such a way that said covering has been modified so that it may include a substantially prismatic profile (26), which exhibits regularly spaced incisions (27).
As may be seen in FIG. 4, each incision (27) comprises a mouth (28) which allows the optical fibre conductor (31) to be pressed into position by any known means so that it may slide through the passageway (29) until it (31) is situated in the cavity (30), in such a way that loops (34) are formed, as may be seen in FIG. 4, forming a complete circuit, in such a way that the ends of the conductor (31), (32 and (33), may be connected by suitable means to the unit which the system includes for measuring light conductivity.
Once the optical fibre (31) is positioned inside the cavity (30), via the mouth (28) of the passageway (29), any known system is used to position an adhesive or to effect subsequent welding, in such a way that said optical fibre conductor (31), in the form shown in FIG. 1, cannot be displaced.
An additional aim of the present invention is that the anti-pinching system should dispense with a reference value stored permanently prior to actuation of the system, that is to say that the anti-pinching system operates between a reference value, which will be that measured in the instant prior to raising the window, not shown in the Figure, and the modified value obtained when said value is modified by the imprisonment of an object between the upper edge of the window and the window frame.
The arrangement of the optical fibre conductor (31) in loops (34) inside the profile (26), see FIG. 4, allows easier detection of any pressure thereon which may result from trapping an object between the upper edge of the door frame and the upper edge of the window than when the optical fibre conductor (31) of the main patent is disposed along the frame.
Once the optical fibre conductor (31) has been positioned inside the profile (26), the latter and the incisions (27) are covered with adhesive or welded, so as to be subsequently introduced by suitable means into the internal covering of the frame.
The subject matter of the present Patent has been adequately described, in relation to the attached drawings, and it will be understood that any modifications in detail may be made to the same which are considered advantageous as long as the proposed variations do not alter the essence of the invention. | A system which takes direct action to reverse the rotation of the window driving motor includes an optical fiber conductor arranged inside a substantially prismatic profile forming loops at the points where said conductor enters and exits from a series of incisions formed at regular intervals in the lateral areas of said profile. The profile is fitted inside a covering in the frame of a door. The incisions comprise a mouth for insertion of the conductor through a passageway which ends in the cavity wherein the conductor is retained by an adhesive or the like. The optical fiber conductor may be arranged continuously over the entire length of the perimeter of the frame or over parts thereof. | 4 |
REFERENCE TO RELATED APPLICATION
[0001] This application is a continuation-in-part of application Ser. No. 08/973,696, filed Dec. 8, 1997 to the same inventor and entitled VALVE CONTROLLED FLOW INTO A TUBE.
BACKGROUND OF THE INVENTION
[0002] This invention relates to a method and apparatus for attaching a probe in a non-invasive manner to the skin of a patient. The invention also involves the control of pressure/vacuum internally or externally of the tube, for example, the controlled reduction of vacuum in the tube. In one specific arrangement, the invention relates to a non-invasive medical probe in which a suction cup is secured to a patient's skin, for example the scalp of a foetus, and a method of using the probe.
[0003] In EP-A-0525021 there is described a non-invasive medical probe for monitoring a patient's condition. The probe comprises a source of suction, which may be a bellows, or other type of pump, connected by a tube to a resilient walled suction cup for application to a patient's skin. With the suction cup in contact with the patient's skin, the bellows or other pump is actuated to apply vacuum through the tube to secure the cup to the patient's skin. Mounted within the cup is an electrode for making contact with the patient's skin following evacuation of the cup, the resilience and form of the cup being such that the resilient wall deforms so that the electrode is drawn down relative to the peripheral rim of the cup and makes the required contact with the patient's skin. A signal is thereby obtained at the skin surface which is responsive to a varying condition of the patient. In the particular embodiment described, the suction cup is for attachment to the scalp of a foetus with the rim of the cup in sealing contact with the surface of the scalp.
[0004] A relatively high vacuum is required to secure the suction cup. The probe needs to remain attached for long durations, e.g. hours, but this creates a red mark on the skin the size of the suction cup. While not harmful, the mark is unsightly and may take up to a day to fade away. It is thus undesirable.
[0005] However, it has been found that the level of vacuum which is necessary to maintain the cup in place even during movements of the foetus head can be substantially lower than the initial vacuum necessary to secure the cup.
SUMMARY OF THE INVENTION
[0006] According to the invention there is provided a method of controllably reducing vacuum in a non-invasive medical probe having a source of vacuum interconnected with a suction cup by a resilient walled tube, comprising creating a valve aperture in the wall of the tube at a desired location through which aperture no appreciable leakage will occur when vacuum is applied and the tube is in a relaxed state, whereby with the suction cup secured by vacuum on a patient's skin, application of a force to the tube wall will open the aperture and permit a controlled reduction of vacuum in the suction cup to a specified amount, and releasing the force will permit the aperture to close so that lower vacuum is maintained and the suction cup continues to be secured on the patient's skin.
[0007] The step of maintaining lower vacuum mentioned throughout includes either constant or varying vacuum consistent with the suction cup or other applicator remaining secured.
[0008] In the preferred embodiment of the invention the probe is adapted for application to the scalp of a foetus with the rim of the suction cup in sealing contact with the surface of the scalp.
[0009] The invention also provides a method of enabling a controlled flow into a resilient walled tube inside which the pressure is lower than outside the tube, comprising creating a valve aperture in the wall of the tube in a desired location through which no appreciable leakage will occur when the tube is in a relaxed state, but which aperture will open on application of a force to the tube wall and permit a controlled flow therethrough into the tube, and which aperture will close when the force is released.
[0010] The invention further provides a method of controlling flow into a resilient walled tube inside which the pressure is lower than outside the tube, which tube has in its wall a preformed valve aperture capable of opening and closing when a force on the tube is respectively applied and released, the method comprising applying said force to open the aperture and to permit a controlled flow therethrough into the tube, and releasing said force so that the aperture closes and the flow stops.
[0011] The term controlled flow means flow which can be accurately interrupted at predetermined levels of pressure inside or outside the tube and/or the magnitude of the flow can be accurately adjusted. Such interruption is effected by releasing said force to allow the aperture to close, and adjusting the flow is effected by varying the applied force.
[0012] In one embodiment, the tube contains a vacuum, and upon opening the valve aperture the vacuum in the tube is controllably reduced so that lower vacuum is maintained in the tube. Preferably the tube interconnects a source of vacuum and a suction applicator.
[0013] Alternatively, upon opening the valve aperture, an overpressure outside the tube is controllably reduced or a controlled flow into the tube is generated. Preferably the portion of the tube containing the valve aperture is located or adapted for location in a chamber containing a fluid at said higher pressure. In this case, the force to open the valve aperture may be remote controlled from outside the chamber.
[0014] Preferably the vacuum reduction/pressure flow occurs at a substantially constant rate and/or amount.
[0015] It is also preferred that said force on the tube wall is applied by bending. Preferably the bending force acts through the valve aperture thereby opening the valve aperture.
[0016] The valve aperture may be created by piercing the tube wall radially, e.g. by a needle having an end which is chamfered to a V-shape to form a line end. Preferably the line end of the needle is orientated transversely to the axis of the tube.
[0017] Slicing transversely through a resilient tube to a depth which reaches the inside is known for creating a valve which opens when the tube is bent and shuts when the tube returns to a relaxed state, but the ingress of air during bending of the tube cannot be controllably stopped at a specific level or the rate of flow adjusted, especially when a relatively small quantity of fluid is involved.
[0018] The invention still further provides a non-invasive medical probe comprising a source of vacuum interconnected with a suction cup by a resilient walled tube, the cup being adapted to be secured by vacuum on a patient's skin, wherein means are provided for controllably reducing the vacuum to a specified amount, after which lower vacuum can be maintained until the cup is removed.
[0019] Preferably the control means are provided in a tube and preferably is a valve aperture in the wall of the tube at a desired location through which aperture no appreciable leakage will occur when vacuum is applied and the tube is in a relaxed state, whilst with the suction cup secured on the patient's skin application of a force to the tube wall will open the aperture and permit a controlled reduction of vacuum in the suction cup to the specified amount, and releasing the force will permit the aperture to close so that lower vacuum is maintained and the suction cup continues to be secured on the patient's skin.
[0020] The source of suction is preferably a bellows attached to one end of the tube.
[0021] For bending the tube in a specific manner and location to open the valve aperture, the tube is preferably provided with finger holding means, preferably adapted to be used single-handedly.
[0022] Means may be provided for measuring the reduction in vacuum. The measuring means may be a calibrated elongate member, which in the case of the source of suction being a bellows or other expandable means for creating suction extends longitudinally of the suction means.
[0023] The invention still further provides a non-invasive medical probe comprising a suction cup adapted to be secured by vacuum to a patient's skin and supporting an electrode, a source of vacuum, and a resilient walled tube structure connecting the source of vacuum to the suction cup, wherein the source of vacuum comprises a resilient bellows operative when fully compressed then released to apply to a predetermined low level of vacuum to the suction cup and means for enabling the bellows to be further extended manually in order to increase the vacuum applied to the suction cup to a higher level.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] The invention will now be described further, by way of example, with reference to the accompanying drawings, in which:
[0025] [0025]FIG. 1 is a perspective view of a non-invasive medical probe having a bellows interconnected to a suction cup by a resilient walled tube;
[0026] [0026]FIG. 2 illustrates the bellows fully compressed prior to securing the suction cup on a patient's skin and the tube portion adjacent to the bellows in a relaxed state;
[0027] [0027]FIG. 3 shows the suction cup secured to the head of a foetus and the bellows partially expanded;
[0028] [0028]FIG. 4 shows the tube portion bent and the vacuum reduced to a specified amount, the bellows still being partially contracted;
[0029] [0029]FIG. 5 is a detail of the tube portion in the vicinity of the slit aperture provided for controllably reducing the vacuum;
[0030] [0030]FIG. 6 is a similar view to FIG. 5, showing the tube portion bent and the slit aperture open;
[0031] [0031]FIG. 7 illustrates a needle for creating the slit aperture in the tube portion; and
[0032] [0032]FIG. 8 is a view generally similar to that of FIG. 1 showing an alternative embodiment of the invention.
DETAILED DESCRIPTION
[0033] The embodiments described below are non-invasive probes of the same general type as the probe described in EP-A-0525021.
[0034] Referring to the drawings, the probe has a suction cup 10 intended for attachment to the head 11 of a foetus for the purpose of monitoring characteristics of the foetus. However, the suction cup is also capable of being applied to a patient's skin more generally, and the invention is not limited to the application of the suction cup on a foetus.
[0035] The suction cup 10 has a resilient wall 12 and a peripheral rim 13 whereby vacuum from a vacuum source secures the cup in the desired location. In this embodiment, the vacuum source is a bellows 14 interconnected to the suction cup by a tube 15 .
[0036] Mounted within the suction cup is an electrode 16 for making electrical contact with the foetal skin. A second electrode formed of coiled wire 17 is provided outside the suction cup for making contact with the vaginal wall. Both electrodes are connected by wiring 18 to diagnostic monitoring apparatus 19 .
[0037] Therefore, as described in EP-A-0525021, the probe is used by holding the suction cup 10 in contact with the head 11 of a foetus with one hand, whilst preferably holding the bellows 14 fully contracted (FIG. 2) with the other hand. Allowing the bellows to expand will apply vacuum within the suction cup 10 which causes the resilient wall of the cup to deform by bending and to draw down the electrode 16 into contact with the scalp of the foetus as the cup becomes secured on the foetal head (FIG. 3).
[0038] At this stage, the bellows 14 is still partly contracted because a relatively high vacuum, typically between 300 and 500 millibars, has been applied to secure the probe in position. It is often required that the probe is kept secured for some time, perhaps a few hours, and such a level of vacuum can create a temporary marking of the foetal skin which is undesirable. However, it has been found that a lower vacuum of, say, 40 to 100 millibars is sufficient to retain the cup 10 in place despite movements of the head of the foetus.
[0039] For the purpose of reducing the level of vacuum to a specified amount, there are provided tubular valve control means which will now be described in detail. The valve means comprises a short intermediate tube portion 19 between the tube 15 and the bellows 14 . The intermediate tube portion 19 is impermeably sealed to a funnel 20 of the bellows at one end, and to the adjacent end of the tube 15 at the other end. In this embodiment, the internal diameter of the tube portion 19 is greater than the diameter of the tube 15 and is thus constructed separately from the tube 15 . Mounted on the tube portion 19 is a finger holding means 21 adapted to be held between two fingers and thumb of the user's hand which has previously actuated the bellows to apply the vacuum. In this embodiment, the finger holding means are two individual parts mounted at either end of the tube portion 19 .
[0040] Between the finger recesses 22 , 23 on one side of the tube portion 19 , and therefore on the opposite side from the thumb pusher 24 , there is created a transversely orientated narrow slit aperture 25 which extends radially through the tube wall. In this embodiment the slit 25 is formed by a needle 26 having an end 27 chamfered by grinding on opposite sides to a V-shape (FIG. 7). The end 27 is thereby pointed with a line edge 28 , and for creating the slit 25 the needle is orientated with the line edge transversely to the axis of the tube portion 19 . It has been found that use of such a needle in this manner creates an aperture 25 which will not leak, at least to an appreciable extent, when vacuum is applied and the tube portion 19 is in a relaxed state (FIG. 5). However, when inward finger/thumb pressure is applied, the tube portion 19 will bend and the slit 25 opens (FIG. 6). Vacuum within the tube portion 19 is thereby reduced, and the bellows 14 will expand by a corresponding amount.
[0041] Attached to the part of the finger holding means 21 adjacent the bellows 14 is a calibration stick 29 extending parallel to the bellows. At the free end of the stick 29 , markings 30 are provided which are calibrated to show the user the extent by which the bellows 14 has expanded and thus the extent by which the vacuum has reduced.
[0042] Alternatively, other measuring means may be provided which essentially comprises a non-expanding elongate member which remains stationary relative to a part of the bellows or other expandable means for creating suction, such as a syringe, whereby it is capable of measuring expansion of the bellows or other suction means.
[0043] In use, the vacuum tends to constrict the valve slit 25 . Hence as the vacuum becomes less, the slit will open further for a given degree of bending of the tube portion 19 . This compensates for the reduced draw of the reduced vacuum, and thus results in a flow rate and a vacuum reducing rate which are substantially constant. The rate of flow and thus the rate of vacuum reduction can be controlled by varying the amount of bending.
[0044] When the vacuum has been reduced to a specified amount, the thumb pressure is removed, and the tube portion 19 returns to its relaxed state whereby the slit recloses. The lower vacuum, which is sufficient to retain the cup 10 secure on the foetus head, is maintained until the probe is removed by dislodging the cup either by further bending of the tube portion 19 to reopen the valve means or by depressing the bellows 14 . Indeed at any time whilst the probe is still secured, a further reduction of vacuum could be achieved, if desired, by repeating the cycle of bending and releasing the tube portion 19 so that the slit opens and closes again.
[0045] The resilient material of which the tube portion 19 is formed is suitable for piercing to achieve the slit aperture 25 which is capable of opening and closing immediately so that when the slit is closed the level of applied vacuum is maintained in the cup 10 . The material is also chosen so that it will not cross-link, i.e. it will not naturally reseal itself. Furthermore, for the medical application described above, a material is selected which is inert to gamma irradiation by which the probe as a whole is sterilised before being packaged, and in the case of use in the U.S.A. the material requires to be a material approved by the Food and Drug Administration (FDA).
[0046] It will be appreciated that the suction probe described above is a disposable item. The vacuum control means thus has to be inexpensive, and in the embodiment described the bellows 14 advantageously acts as a gauge to determine the amount by which the vacuum has been reduced, the expansion of the bellows being measured against the calibrated stick 29 .
[0047] The tube portion 19 preferably has a wall thickness so that it will not buckle when it is bent by the finger/thumb pressure. Also, the fact that the tube portion 19 is relatively short and is held rigidly on either side of the slit aperture 25 , enhances the ability of the slit to open when the free, central part of the tube portion is bent, and to reclose when the tube portion straightens after the finger/thumb pressure has been removed. The slit aperture 25 is thus self-closing.
[0048] An important advantage of the embodiment described above is that the valve aperture 25 allows the total flow of air which would be required to reduce the vacuum from the applied vacuum to zero, to be only a few cc, for example as low as 1 cc.
[0049] The invention is not restricted to the specific details of the embodiment described above. For example, the probe may be used in other applications besides monitoring the characteristics of a foetus.
[0050] Also, the principle of reducing vacuum in a tube to a specified amount in a controlled manner may be employed in other applications in which a source of vacuum is interconnected to a suction applicator by a tube. The term suction applicator includes any environment, e.g. a chamber, in which suction is to be applied. The tube may readily be provided with a resilient walled portion having a valve aperture of a kind which is capable of opening and resealing in the manner described, and preferably has finger holding means for applying the necessary pressure to open the aperture and thereby reduce the vacuum in the tube and the suction applicator. Alternatively, other means may be provided for opening the aperture, which means may be remotely actuated.
[0051] Furthermore, instead of the valve aperture being employed to reduce vacuum in the tube, the same principle can be applied to other situations in which the pressure inside the tube is lower than the pressure outside the tube. In one case, the tube portion containing the valve aperture is located, or adapted for location, in a chamber containing a fluid, e.g. air, at a higher pressure than the pressure in the tube. By bending the tube, the valve aperture can be opened to allow a controlled air flow through the valve aperture into the tube either to lower the pressure in the chamber to a specified amount, or to supply air to the tube from the chamber at a controlled rate and amount. In each case, as explained above, the air flow through the valve aperture will be at a substantially constant rate for a given degree of bending, and can be varied by varying the bending force. On releasing the bending force, the valve aperture will close maintaining lower pressure in the chamber or halting the air flow from the chamber into the tube.
[0052] By way of example, the tube may be bent internally of a sealed chamber by a rod inserted within the tube to the vicinity of the valve aperture in the tube wall, or other remote controlled means.
[0053] [0053]FIG. 8 shows an alternative embodiment of the invention. In the embodiment of FIG. 8, a weak bellows 14 ′ is used in place of the strong bellows of the previously described embodiments. When the bellows 14 ′ is fully compressed and then released only the low suction level is produced. The initial, short-term high suction level is achieved by manually expanding the bellows 14 ′ to a greater extent than achieved by its own elasticity. To this end, the bellows 14 ′ is provided with a thumb ring 200 attached to its closed end and a pair of wings 210 arranged one on each side of its open end to be engaged by the second (index) and third fingers. As an alternative to the wings 210 , rings may be provided to act as finger abutments. After being compressed and positioned to seal on the scalp, the bellows is manually stretched between the thumb and fingers to produce the temporary higher suction level. When the bellows is then released, it returns to a safe low suction level which it maintains by virtue of its own elasticity.
[0054] The embodiment of FIG. 8 offers several advantages over the previously described embodiments. First, the need for a pressure relief valve is avoided thus reducing the manufacturing cost and the number of air-tight joints. Second, the operation is fail-safe because it is not possible for the operator to omit inadvertently to release the suction. Third, the application of the probe and control of the pressure can not only be carried with one hand but the need to move between different hand positions is also avoided. Furthermore, the setting of the lower pressure is predetermined by the elasticity of the bellows and does not require calibration.
[0055] It will be clear that other modifications may be made to the probe within the scope of the invention as set forth in the claims. For example, in addition to, or instead of, using a small protrusion at the centre of the electrode plate, a plurality of small protrusions may be provided on the rim of the plate, to help in making electrical contact with the skin through hair on the scalp. | A non-invasive medical probe includes a suction cup adapted to be secured by vacuum to a patient's skin and supporting an electrode, a source of vacuum, and a resilient walled tube structure connecting the source of vacuum to the suction cup, the source of vacuum including a resilient bellows operative when fully compressed and then released to apply a predetermined low level of vacuum to the suction cup and an arrangement connected with the bellows for enabling the bellows to be further extended manually in order to increase the vacuum applied to the suction cup to a higher level, the arrangement including a thumb ring secured to a closed end of the bellows and a finger abutment at an opposite end of the bellows. | 0 |
BACKGROUND OF INVENTION
1. Field of the Invention
The present invention relates to the field of providing synchronous communication, specifically it relates to achieving synchronous communication with a target based on the context of the calling party.
2. Background of the Invention
Traditional telephony relies on the use of telephone numbers to route call requests to a desired recipient. 800 numbers, 900 numbers, group pickup, call forwarding, all allow a specific desired recipient or group of recipients, to be reached based on digits dialed by the calling party, which then undergo number translation (e.g. to a regional 800 destination), or predetermined fan-out (as in group pickup).
800 numbers are implemented in the Public Switched Telephone (PSTN) system via a lookup on a database resident on a Signaling Control Point (SCP). This database maps an 800 number to a physical telephone number. This is accomplished through Signaling System 7 (SS 7 ) signaling which takes the digits entered by the user, and invokes a lookup on the number translation database. The physical PSTN number that is returned is used to do the connection setup. Lookup for 900 calls is similar except for the charging mechanism. Both 800 and 900 number translations rely on a pre-determined (ignoring dynamic personal state) translation. 800 numbers and 900 numbers require that the calling party dial the digits associated with the desired call recipient.
Call forwarding is a service whereby the terminating switch on the path to the called party replaces the original number with a second number that is programmed by the owner of the original number. Call forwarding is thus another form of number translation that is programmed by the end user. Call forwarding requires that calling party dial the digits associated with the desired call recipient.
Call centers are a way that many operators can respond when customers dial a single phone number. Offered by enterprises, or as a telecom service, an incoming call is routed to an Automatic Call Distributor (ACD) which can then routed the call to one of many physical telephones. The selection of a target telephone may be done by one of many algorithms including longest idle, or skills based routing. Target phones traditionally have been collocated with the ACD, but advances in communication have made distributed call centers feasible. Call centers are generally employed by enterprises or by carriers (e.g. for directory assistance). Call centers are reached when the calling party dials the digits associated with that termination.
Traditional telephony requires that the calling party enter an identification indicating the desired recipient in order to make this connection—either a telephone number, a speed dial sequence such as *n where n is a digit or digit string (usually only one or two digits), a spoken name previously associated with a dial number (e.g. as in voice activated dialing), etc. The advent of VOIP protocols such as H323 and SIP (session initiation protocol) allows this to be extended past the traditional PSTN to internet protocol (IP) addresses or other allowed designations; VOIP protocols extend the telephony paradigm to the IP world. To reach an IP destination, a calling user must provide an indication of the desired party to be reached.
The Telephone Number Mapping standard, called ENUM, is a specification to map telephone numbers from the Internet. For a “voice over IP” (VoIP) call, (which by definition originates on the Internet side) that aims to reach a PSTN user, the VoIP call must terminate at a IP-PSTN gateway. ENUM allows for dynamic selection of such a gateway based on the destination PSTN Number. ENUM lookups are accomplished via DNS; in this case, the DNS (Domain Name System), which is the host/service naming and lookup scheme used in the Internet, maps a PSTN number to the name of the Internet host that serves as a gateway to the desired PSTN number.
CTI or computer-telephony integration refers to programming a PSTN interface connected to a computer; a computer is typically connected to a data network, and thus providing a PSTN interfaced card allows a computer to interact with the PSTN network. CTI basically enables a computer to act as an endpoint of the PSTN network, i.e. it appears to be a phone to the PSTN network. The aim of CTI, as the name suggests, is to enable computer applications to be extended to use services from the PSTN network.
The use of a person's location in communications and computer applications is not uncommon today. Users of cell phones are offered services tailored to the location of the cell phone. Examples include emergency 911 calls, movie listings for local theaters, traffic conditions, nearby gasoline sales, etc. The Hertz Company equips some of its rental cares with an interactive device that uses the rental car's location to offer navigation clues to the driver. Research labs have prototyped electronic tour guides on mobile devices for museums, small cities, and retail stores that also use device location to tailor end user services.
We're also used to communications applications that use the context of the person who is the intended target of a communiquéto influence a communications request. A simple example is the busy signal that we've all heard with we attempt to phone someone who's already on the phone. Newer variations on that theme can be experienced when one attempts to contact a person's mobile communication device. For example Nextel's so called DirectConnect® phones chirp in different ways depending on the state of the target person's device.
Communications applications can also show some information about the calling party. For example many phone services offer a feature known as caller ID that provides the calling parties telephone number.
Data from a myriad of physical sensors can extend context beyond location and device activity. Examples include atmospheric measurements, light level, sound pressure level, audio feature analysis, weight and pressure, motion detectors, magnetic door and window switches, etc. Personal medical sensors can also provide data on a variety of physiological measures including pulse rate, blood pressure, body temperature, electronic impulse activity and resistance, etc. A familiar example of such an application is the so-called lie detector machine.
Context-aware computing has included message and call delivery, based on recipient (eg called party). Two examples are the Etherphone system from Xerox® Parc and Active Badge system from Olivetti®, both of which route an incoming call based on the called party's location. The Active Messenger system (AM) from MIT routes an incoming message to a suitable device near the called party, e.g. pager, phone, fax. However, the routing in these cases is not done based on attributes of the caller.
Traditional telephony requires that the calling party recall numbers or access codes for desired called parties. With many potential called parties this becomes difficult. Speed dialing provides simple access, but still requires that the calling party recall access codes and further requires a prior number selection and association with the speed dialing code. What is needed is a way to simplify access for the calling party to reach appropriate called parties, responsive to current calling party status, such as expected appointments.
Voice calling requires that the calling party recall names or designations of called parties. With many potential called parties, this becomes difficult. What is needed is a way to simplify access for the user to appropriate recipients.
Calendars may be available on different devices including paper calendars, PDA based calendars and so on. These can allow a user to determine the appropriate person to call based on expected appointments, but these may require reading, reentering numbers into a phone, and so on. What's needed is a way of reaching people based on caller context (eg expected appointments).
Further, determining an appropriate person may require an understanding of roles and assignments. What's needed is a way of reaching such called parties based on their roles, independent of their phone number or IP address.
Rules based routing—Calls once received (e.g. at a help desk) may be routed to an appropriate destination (e.g. operator) based on rules such as time of day (for night shutdown), based on perceived content of the call (e.g. based on origination, route to appropriate operator with correct linguistic skills), based on calling line id (eg route to assigned CRM rep for this customer). This mechanism is all called side determined. What is needed is a way to determine a called objective based on callers context.
What is needed is a method and system which makes it easier to use corporate data, such as calendar information, assignment lists, etc. to make more effective voice calls; and which uses the context to both the called and calling parties.
SUMMARY OF INVENTION
Disclosed is a method and system for allowing a user to request a synchronous connection, for example a voice call connection, to an appropriate party determined by the context of the user initiating the call. Whereas the prior art identifies the party to be called by having the call initiator provide an identifying number (for example a phone number or PIN number for the called party), the present invention selects the party to be called based on the caller's identification and awareness of the caller's situation.
In an embodiment of the invention, the connection details are determined by awareness of the calling situation (context). The context of the calling party includes but is not limited to both corporate and personal data obtained from (1) calendars, (2) the location, activity and network address of personal devices such as cell phones, office phones, home phones, laptop and desktop computers, automobiles, etc., (3) special-purpose sensors that detect motion, sound, light, pressure, etc. deployed in spaces frequented by the call participants, and (4) RFID readers that detect the presence of companion devices (for example RFID tags) that have been provisioned with identification numbers associated with the call participants.
In a still another embodiment, the invention permits delivery of the communication responsive to the called party context which may include the same sources as detailed above for the calling party. An object of the present invention is to require a single action from the calling party to completely specify the target and connection details for the call.
Various other objects, features, and attendant advantages of the present invention will become more fully appreciated as the same becomes better understood when considered in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the several views.
BRIEF DESCRIPTION OF DRAWINGS
FIG. 1 illustrates a telephone dialing system according to a conventional dialing system.
FIG. 2 illustrates an inventive system according to an embodiment of the present invention.
FIG. 3 shows a flowchart of an embodiment according to the present invention.
FIG. 4 shows a flowchart for accessing caller context information according to an embodiment of the present invention.
FIGS. 5A and 5B show flowcharts for determining a connection objective according to an embodiment of the present invention.
DETAILED DESCRIPTION
Before a detailed description of the invention, it can perhaps be best understood by a couple of illustrative examples of its use.
EXAMPLE 1
A cell phone user (calling party) in the car wants to join his or her currently calendared conference call. The calling party doesn't know the number. Calling party dials their personal number, and is connected to the call. The inventive system here has received the indication that the calling party has dialed in, has retrieved calendar information, has analyzed the calendar information and determined that the calling party is supposed to be attending a voice conference call, and has initiated the conference call (including entering the password).
EXAMPLE 2
A cell phone user (calling party) has a meeting scheduled with a colleague but is late. The calling party doesn't know the colleague's number. The calling party dials their personal number, and is connected to the call. The inventive system here has received the indication that the calling party has dialed in, has retrieved calendar information, has analyzed the calendar information and determined that the user is supposed to be meeting a specific colleague, has accessed context (e.g. presence information) related to the colleague, has determined a method of reaching the colleague for a synchronous communication, and has initiated the synchronous communication.
EXAMPLE 3
A repairman (calling party) is out in the field and is about to finish his job. He dials his number and is connected to his next appointment. The repairman doesn't know who the appointment is with. The inventive system here has received the indication that the calling party has dialed in, has retrieved assignment information (eg to-do list), has analyzed the assignment information, determined that the number of the next assignment permissible for this time of day (eg if homeowner is only there between 11 and 1, and the time of day is now 12:45, indications are that this one should be skipped and the repairman directed to the next assignment), and has initiated the call.
EXAMPLE 4
An employee is at home working on a cable modem. He is supposed to join a conference call with e-meeting. He dials his number and is connected the conference call; the e-meeting content pops up on his screen. The employee doesn't know the number. The inventive system here has received the indication that the calling party has dialed in, has retrieved calendar information, has analyzed the calendar information and determined that the calling party is supposed to be attending a voice conference call, and has initiated the conference call (including entering the password). Further, presence information regarding the calling party shows that they are “up” on the cable modem and therefore available for the e-meeting data. The data is retrieved (based on the calendar info) and pushed to the screen. Note that a colleague may dial into the same conference, but if the presence information does not indicate the availability of a high bandwidth connection may not receive the e-meeting data, or may receive a transcoded version appropriate to the nature of their connection.
EXAMPLE 5
A patient calls the hospital, or the doctor's office, and identifies and authenticates herself (for example she keys in her identity code and password). Based on her context (for example her medical condition, patient record, her doctor's notation about whether she calls only when necessary, the time of day), she is able to directly reach the physician. When she is connected to the physician, her electronic patient record is transmitted to the doctor's PDA.
In these examples, the calling party is identified by the personal number that is dialed. This is to provide ease of use, but a similar service may also be provided by dialing a common number, Identification of the calling party can be provided via calling line ID (which then restricts callers to a single device), or other means. Some of these means can also be used to provide security. For example, identification may be via speaker identification or other biometric identification, which can also provide authentication information. Further security can be provided by requiring a password. Further, security can be preferentially applied—if a calendar entry is confidential, it may require an authentication step, and otherwise no security may be required.
FIG. 1 shows a functional diagram of a traditional phone dialing system. Element 110 is a device used by the person or PC program initiating the phone call. Element 110 sends out a dialing signal 130 consisting of the phone number (or the IP address) of call target element 120 . The signal format 130 can be SS 7 for PSTN phones, as well as SIP or H323 signaling for VoIP phones and PC softphones. The call network element 150 can perform the possible call routing services 160 (e.g., call forwarding) based on this call target phone number or IP address. The call network element 150 can be TDM circuit switch network or IP network. The call routing service elements 160 can be the TDM circuit switches or the application servers in the IP network. The locations of the routing service elements 160 can be centralized or distributed. The call routing service element 160 can then decide based on internal pre-configured database 190 to route the call to the call target 120 or forwarding the call to the actual called target 170 .
FIG. 2 shows an inventive system 200 according to an embodiment of the present invention. Element 210 is a device used by the person initiating the phone call which is capable using the network element 250 to inform a call manager element 260 of the request to make a phone call. Element 210 can be a wire line or wireless telephone, a laptop or desktop computer with a wired or wireless network connection and telephone software, or any physical object with an embedded telephony capability (for example, automobiles, clock radios, set top boxes, video games, etc.). The call network element 250 is any collection of wireless and wired components capable of communication with the call participant's phone call elements 210 and 230 , and also capable of using the phone call manager service provided by element 260 . Element 260 is a network-based service capable of identifying the initiator of the call, and determining that person's context using another network-based service shown as element 270 . If the call request triggers an associated action, the network service provided by element 260 is capable of managing it. Network service element 260 can be provided by a dedicated or shared computer running appropriate software and having hardware interfaces to network element 250 . Identification of the person initiating the call can use any of the existing methods for this purpose, including individual access number, passcodes and PIN numbers, passwords, biometric data and voice analysis, etc.
Network service element 270 can also be provided by a dedicated or shared computer running appropriate software and having hardware interfaces to network elements 220 and 240 , and provides for the accurate identification, storage, and aggregation of personal data that can be used to remain aware of the context (situation) of the participants in the call. The network elements 220 and 240 include computing and sensing technologies that are aware of the call participant's (1) calendars, (2) the location, activity and network address of personal devices such as cell phones, office phones, home phones, laptop and desktop computers, automobiles, etc., (3) special-purpose sensors that detect motion, sound, light, pressure, etc. deployed in spaces frequented by the call participants, and (4) RFID readers that detect the presence of companion devices (for example RFID tags) that have been provisioned with identification numbers associated with the call participants. Note that element 240 is optional in the inventive system. An embodiment of the present invention can be realized without element 240 . Inclusion of element 240 provides additional opportunity to tailor the communication to the state of the target call participant.
FIG. 3 describes a method according to an embodiment of the present invention. We begin with block 310 , and receive a context communication request. Receiving a context communication request may entail receiving digits or access codes from a telephone handset, wired or wireless. This includes but is not limited to a user dialing a personal communication number (e.g. a 7 or 10 digit number which is the same for all calls), speaking a command, depressing a button or touch screen on such a device. Alternately, it may include receiving a single user action such as clicking a button on a screen, indicating a selection on a PDA.
The context communication request differs from a caller placing a normal call in that the normal call requires the indication of a connection target, or called party. The called party is indicated either by dialing digits representing the called number, by using abbreviated dialing, voice dialing, or in the case of a VOIP connection potentially indicating a VOIP destination IP address. Such digits or other indications differ with the target of the call. However, the context communication request does not change.
We continue with block 320 . Details of block 320 may be found in FIG. 4 . In block 320 we identify the initiating or calling party, and access context information related to the calling party. Such information includes but is not limited to (1) corporate or personal information including calendars, (2) the location, activity and network address of personal devices such as cell phones, office phones, home phones, laptop and desktop computers, automobiles.
In block 330 , responsive to the context accessed in block 320 , we determine a connection objective. Details of this may be found in FIG. 5 . A connection objective includes but is not limited to a conference call, a person, a room, or a role. Determining may be based solely on calling party context, or may include iterative processes based on initial connection objectives and mediated by called enterprise or called party policy, availability, connectivity or other factors. In one embodiment, the connection objective is determined based on calling party calendar. In a second preferred embodiment, the connection objective is dynamically determined based on role and assignment data. That is, in this embodiment, the connection objective may be determined based on enterprise work force practices including optimization of mobile workforce.
In block 335 we determine an action associated with the connection objective. The action may be determined based on connection objective or may be based on at least one of calling party context, history of previous connections between the calling party and the connection objective, called party context (including role), personal or enterprise policy, rules or algorithm. The action may be determined by rules associated with at least one of the calling party, an entity associated with the calling party such as calling party enterprise, a service associated with the calling party. The action may include but is not limited to transmitting data (including image data), transmitting a pointer or URL allowing data access, creating a log record, instigating a notification to the connection objective, instigating a notification to a third party.
As an example, a calendar entry may include the words: “Call Dr. Doe to discuss X-RAY for Jane Smith”. The connection objective would be Dr. Doe, and the associated action, determined by analyzing the calendar entry, would be to transmit the latest x-ray associated with Jane Smith to Dr. Doe in conjunction with completing the connection action. Had the calendar entry specified “Call Mrs. Smith to discuss x-ray of her daughter Jane Smith” the associated action determined would be different.
The associated action may be taken before the connection action, in parallel with the connection action, or after the connection action as determined by the algorithm determining the associated action.
In block 340 we execute a connection action to reach the connection objective determined in block 330 . Once the connection objective is determined, a connection action is further determined. Such an action may be based on table or database lookup or may be mediated by called party context including but not limited to location, called enterprise or called party policy, availability, connectivity, connections status or other factors. A connection action may include but is not limited to dialing a telephone number, initiating a VOIP connection, connecting to a voice mail box, redirecting a call, connecting to a conference or connection service. If the connection action fails, error correction may take place.
Intermediate results may be logged and used for management and maintenance purposes as well as for better resolution of connection objectives for future connections.
FIG. 4 provides details of block 320 . FIG. 4 describes the part of our inventive method that identifies the caller and obtains relevant context about the caller. In block 410 we acquire information to identify and optionally authenticate the caller. Identification information can include calling line identification, identification codes, analysis of voice audio data for the purpose of identification, personal telephone access numbers that are unique for each potential caller, unique codes embedded in personal devices (for example cell phone SIM codes), and biometric measures including fingerprint recognition, face recognition, iris recognition, and hand geometry. The identity of the caller may be authenticated using simple passwords or passcodes, or more elaborate schemes using public key encryption technology (for example digital signatures and certificates). In block 420 the personal identification and authentication data obtained from the caller is compared with a store of registered users that enumerates authorized users and privileges, and can be used to validate the identification and authentication data obtained from the caller. If the caller fails the identification, authentication, and or authorization tests, the call is terminated as shown in block 450 . In an embodiment, calls reaching block 450 may be transferred to an operator, or begin a process which employs alternate identification and authentication methods.
For callers passing the test in block 420 our method next acquires personal context information as shown in block 430 . This includes data from corporate and personal calendars, entries from relevant schedules and job assignment ledgers, and the like. It is noted that this data may be obtained from a single store, or may be aggregated from a set of stores and network services.
In block 440 the caller's context supplement is with real-time sensor data. Relevant data includes but is not limited to (1) the time of day and the caller's time zone, (2) the caller's location as determined by GPS (global positioning system) coordinates, the location of relevant communication network resources (for example TCP/IP subnets), cellular towers, and the like; (3) data from special-purpose sensors that detect motion, sound, light, pressure, etc. deployed in spaces frequented by the caller (for example in the caller's automobile); and (4) personal medical sensors that report the caller's physiological state.
The flowchart returns back now to block 330 of FIG. 3 .
FIG. 5A describes the method for determining a connection objective. In an embodiment, as shown in FIG. 5 , first is considered the user calendar entries as the most important context. Other context is considered after calendar. In another embodiment, a confidence factor, within block 330 , is associated with all connection objectives based on the manner in which they are determined. Only connection objectives exceeding a preset threshold are utilized in forming connections without further user validation.
Beginning with block 505 and using the context information accessed in FIG. 4 , if a calendar entry is available for the current or approaching time period for this caller, we proceed to block 510 . If a calendar entry is not available, we proceed to the A marker, and block 570 on FIG. 5 B.
Block 510 examines the calendar entry. Calendar entries may be freeform or may abide by one of several accepted or ad-hoc standards. Information in the calendar entry may accessible via XML, via keyword or through interpretation of structure. In block 510 we analyze the calendar entry to determine if there is a telephone number target within the entry. If the calendar entry is freeform, then text analysis can be used to identify the telephone numbers within the entry. Note that there may be multiple phone numbers (eg a phone number associated with the secretary that set up the meeting or call). Keyword analysis, semantic analysis, user history and other techniques can be used to identify the correct number from among several which can be dialed for the user to successfully initiate the action referenced by the calendar entry. While we discuss telephone numbers in block 510 , it is clear that IP addresses or other data descriptions can also be used to indicate a destination objective. Analysis in block 510 is intended to refer to not only telephone number determination but also other forms of data address determination, If the decision in block 510 was that a target telephone number is available, we proceed to block 515 and provide the phone number as a connection objective (CO). In block 540 , we return to the process of FIG. 3 and block 340 .
If the decision in block 510 was that a target number was not available, we proceed to block 520 . In block 520 , we analyze the calendar entry to determine if there is a target name or location available in the entry. This can be determined by text analysis techniques of varying sophistication, from looking for capital letters beginning a name, to looking for keywords such as “conference room”, to more sophisticated analysis.
If in block 520 we determine a name or location we proceed to block 525 . Here we associate a connection objective with the name or location found in block 520 . If the target is an employee of the same enterprise, a directory lookup may serve to find the correct connection objective (eg phone number, IP address). Other data sources may be used to match the name or location with a connection objective including but not limited to calling party profile or records, calling party call history, customer records (eg “talk to Harry” may be resolved as a desire to call Harry Jones, a customer assigned to the employee making the call), directory assistance (eg “meet Joe at the Westchester Marriott” may result in determining the phone number for the Westchester Marriott through a commercially available directory assistance service). While we discuss telephone numbers in block 525 , it is clear that IP addresses or other data descriptions can also be used to indicate a connection objective. In addition to phone numbers or IP addresses, the connection objective may be determined to be a connection service. That is, through explicit entry or through corporate policy, the connection objective determined from the calendar entry may resolve to providing connection to an enterprise or third party service which will then complete the required actions. The connection service may be one that actively connects to another target endpoint, or passively waits for others to connect to the service with the same objective, and join all of the callers (as commonly experienced when dialing into a conference call). We proceed from block 525 to block 530 , and provide connection objective information, and then to block 540 . In block 540 , we return to the process of FIG. 3 and block 340 .
If the decision in block 520 was that no name or location is available we proceed to block 550 . Decision block 550 determines if any information is available in the calendar entry. If the entry is blank, we proceed to block 570 .
If the entry is not blank, we proceed to block 555 and examine the entry for keywords. For example, the entry may say “Meeting for project Alpha”, or “Call broker”. Text analysis determines which of these are potential indicators of connection objectives. In a preferred embodiment, terms in calendar entries are checked against a list of keywords. Terms are units of text including but not limited to words, abbreviations, or special symbols. Keywords can be created manually or automatically. Examples of automatic knowledge profile creation from which such keywords can be harvested may be found in the products of companies such as Tacit Knowledge (www.tacit.com).
Proceeding to block 560 and seek to associate a connection objective with the keyword. For example, a group of colleagues may be associated with project Alpha, and a connection objective of a conference call with all of them may be determined. As a second example, while the method may conclude that “broker” is a keyword, no further detail and therefore no connection objective may be determined. As described for block 525 , the connection objective may be a connection service. If in block 560 we have associated a connection objective with at least one keyword found, we proceed to block 525 , and perform the processing already discussed.
If in block 560 we do not associate a connection objective with a keyword, or have found no keywords, we continue to block 570 and access a context hierarchy. If calendar is the only context to be employed in the method, then the hierarchy is empty and we proceed to block 585 .
This hierarchy describes what sources of context are to be examined next in order to determine a connection objective.
For example, in an appliance repair business, “gold” customers may be given a specific appointment, while other customers must wait their turn. The repairmen in such a company have calendars representing appointments they must keep, and when no appointment is scheduled are free to handle the next customer. In this example, to initiate a confirming call before visiting, the inventive method first considers calendar, then role (repairman), location and assignments (to determine the next customer to be seen). While FIG. 5 describes a preferred embodiment of a context hierarchy to be considered, it is clear that an alternate implementation of the inventive method may employ not a hierarchy of context sources, but instead use a rules engine which analyzes data from multiple context sources to determine a connection objective.
In blocks 575 and block 580 we consider the context from the sources established in block 570 , and examine caller context to determine a connection objective. If a connection objective is determined for any of the sources of context, we proceed to block 525 and the processing described. If no connection objective is determined, we continue to block 585 .
In block 585 we set the default connection objective, and in block 590 optionally confirm it with the user. The default connection objective may be established through user profile, corporate policy, or other means. The default connection objective may provide a call termination point for subsequent conferencing. This enables parties with mismatched calendar entries to engage in “meet me” conferencing. That is, if two parties intend to meet, and only one has placed the appointment on the calendar, the inventive method allows the party without the calendar entry to dial in first and later be conferenced with the appropriate colleague. We return to block 525 and processing described.
It is to be understood that the provided illustrative examples are by no means exhaustive of the many possible uses for my invention.
From the foregoing description, one skilled in the art can easily ascertain the essential characteristics of this invention and, without departing from the spirit and scope thereof, can make various changes and modifications of the invention to adapt it to various usages and conditions.
It is to be understood that the present invention is not limited to the embodiments described above, but encompasses any and all embodiments within the scope of the following claims: | A method for routing a communication connection request includes the steps of obtaining context information from a communication connection requestor in response to a communication connection request. The steps further include using the context information to determine a communication connection action, and connecting the communication connection requestor based upon the connection action. | 7 |
BACKGROUND OF THE INVENTION
This application relates to a three-way catalyst for the treatment of exhaust gases.
Three-way conversion (TWC) catalysts are capable of stimulating both the oxidation reactions for hydrocarbons and carbon monoxide (HC and CO) and also the reduction reaction of NO x . Known three-way catalysts contain one or more platinum group metals, dispersed on a base (support) with a well-developed surface of stable oxides, usually γ-Al 2 O 3 with the addition of oxides of Zr or Ce, together with one or more oxides of the alkaline-earth metals Ba, Ca and Sr. For example, see U.S. Pat. No. 4,171,288. The base is coated onto a carrier which can be a ceramic block (e.g. cordierite ceramic of Corning Inc.), or a spirally wound metal foil of Fe-Cr-Al or other corrosion-resisting materials on iron base.
In addition to platinum group metals, three-way catalysts are known which contain one or more oxides of d-elements (see U.S. Pat. No. 4,552,733), which can increase the efficiency of platinum group catalysts by maintaining oxygen availability through the convertible accumulation of oxygen during the current cycle and by suppressing generation of the toxic gases H 2 S and NH 3 .
Commercially available three-way catalysts have two main disadvantages. First, they generally include several precious metals, i.e, Pt, Pd and Rh or sometimes Pt and Rh, which are costly and present serious technical problems for their recovery. Second, modern engines have higher exhaust gas temperatures. This accelerates thermal breakdown of the structure and composition of the catalytic surface, for example in the creation of aluminates, resulting in significant a decrease of catalytic efficiency over time.
U.S. Pat. No. 5,021,389 discloses a three-way catalyst. This catalyst has a four-layer structure formed from an alumina base, a discontinuous coating of lanthanum oxide disposed on the base, a discontinuous coating of palladium disposed cover the lanthanumoxide coated base, and a discontinuous coating of titanium dioxide disposed on over the palladium coated base. This structure is said to provide a synergistic enhancement of the catalytic effectiveness of the Pd, allowing greater efficiency through the use of a low cost material (titanium dioxide) which could at least in theory reduce the cost of the catalyst.
U.S. Pat. No. 5,013,705 discloses a three-way catalyst in which it is possible to use palladium instead of higher-priced platinum by including a high amount of cerium dioxide in the formulation.
The second disadvantage has been overcome to some extent by introducing in the substrate composition, thermo-stimulants such as zircon, alkaline earth metal oxides such as baria, calcia or strontia and/or rare earth metal oxides. See U.S. Pat. No. 4,171,288. In addition, formation of the catalyst in several layers may alleviate this problem, since thermal breakdown of one layer does not destroy the whole catalyst (See, for example, U.S. Pat. No. 5,063,192).
Notwithstanding the numerous improvement which have been made in the field of three-way conversion catalysts, however, there remains a continuing need for a lower cost catalyst which is stable at high temperatures. It is an object of the present invention to provide such a catalyst.
SUMMARY OF THE INVENTION
These and other objects of the invention are achieved by a catalyst comprising a catalyst carrier and first and second catalyst layers formed as discrete layers one over the other on the catalyst carrier with the first layer being formed between the catalyst carrier and the second layer. In the catalyst of the invention, the second layer comprises finely divided nickel needles having a specific surface area in excess of 100 m 2 /g onto which a platinum group metal is deposited. The first layer isolates the catalytic surface from the underlying support and provides an oxygen reservoir, and may advantageously comprise magnetite, cerium oxide and rhenium, and the second layer comprises nickel and a platinum group metal such as rhodium, palladium or preferably platinum. Thus, the invention provides a catalyst which need use only a single platinum group metal, in combination with relatively inexpensive other components.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 shows a three-layer catalyst structure of the invention schematically.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 shows a catalyst in accordance with the present invention schematically. As shown, the catalyst comprises a catalyst carrier 10 and two catalytic layers 11 and 12.
The catalyst carrier 10 in accordance with the invention is advantageously cordierite, a refractory ceramic material.
The first catalytic layer 11 is applied on catalyst carrier 10. This layer isolates the carrier from the second catalytic layer 12 and provides an oxygen reservoir for the catalytic process. Many different compositions are known which can achieve these functions, and these compositions can be used in the present invention.
A preferred composition for the layer 11 comprises iron in the form of magnetite (Fe 3 O 4 ), cerium in the form of cerium oxide (CeO 2 ), and rheniummetal. Each of these materials plays a functional catalytic role in provided effective an effective three-way catalyst.
Magnetite promotes the conversion of CO and, to a certain extent, NO x . In addition, the magnetite helps to form a solid layer, isolating the components of the second layer 12 from the catalyst carrier 10.
Cerium oxide, as well as magnetite is an oxygen carrier that improves the oxidation of CO in rich air-fuel mixtures. Cerium oxide also serves to protect the catalyst from thermal degradation and affects the CO oxidation kinetics, particularly in the low temperature mode, by decreasing the of energy of activation.
The rhenium increases the effectiveness of Pt present in the second layer in the reduction of NO, particularly at temperatures above 500° C. Also, the use of rhenium instead of rhodium commonly used in prior art devices permits a significant reduction in the cost of materials.
Electron microscopy shows that the iron and cerium components of the first layer form a porous coating over the catalyst body. The rheniummetal is deposited in the pores.
The second catalytic layer 12 comprises catalytically active metallic nickel and a platinum group metal. When viewed by electron microscopy, the nickel in the second layer 12 in accordance with the invention is in the form of finely divided needles which are distributed uniformly all over the catalyst surface. The needles are from 0.3 to 1.2 μm, and more commonly 0.7 to 1.0 μm in length, and from about 0.1 to 0.3 μm thick. These needles provide a catalyst with a specific surface area which is much greater than previously known three-way catalysts. In particular, the specific surface area of the catalyst of the invention is at least 100 m 2 /g, more preferably at least 120 m 2 /g.
In a preferred embodiment, the first catalytic layer 11 is applied to the catalyst carrier 10 by first immersing the catalyst carrier 10 in a aqueous solution containing Fe(NO 3 ) 3 , Ce(NO 3 ) 3 and BaReO 4 . The catalyst carrier is immersed in the solution, and then dried. The dried carrier is then heated in a reducing atmosphere to convert the Fe(NO 3 ) 3 to magnetite and the BaReO 4 to metallic rhenium.
The second catalytic layer 12 is formed over the first catalytic layer 11 in two steps. First, the catalyst carrier 10 with the first catalytic layer 11 formed thereon is immersed in an aqueous solution of NiCl 2 and then dried. The wash coated block is then placed in an autoclave in a aqueous solution containing hydrazine, ammonia and optionally thiocarbamide and heated at a temperature of 90° to 100° C. for a period of 2 to 5 hours. The chemical metallization under pressure in an autoclave has two effects. First, it creates a layer having a thickness of about 120-150 μm with Ni content of 25%-40% (from ESCA data). Second, it leads to an accumulation of nickel on the surface by autocatalytic reduction of Ni 2+ . The nickel is in the form of an advanced needle-like coating over the previous layer covering both the external surface of the catalyst carrier and the internal pores thereof. The specific surface area is considerably increased and is suitable for another layer capable of stimulating the conversion of CO, HC, and NO x in lean, stoichiometric and rich air-fuel mixtures in both low and high-temperature modes.
The partially completed catalyst is then washed with water, dried and coated with platinum. The platinum is applied by immersing the catalyst is a solution of H 2 PtCl 6 in Trilon™, a chelating agent used for stabilizing platinum in solution, ammonia and hydrazine. This results in the formation of platinum-coated nickel needles which fully exploit the catalytic synergy of the nickel-platinum compound (permitting the use of minimum amounts of platinum) and further prevents the formation of nickel carbonyl which can easily be carried away in the exhaust gas resulting in deterioration of the catalyst. The number of active sites is also increased, thereby increasing the catalytic action. The specific surface area of the resulting catalyst is greater than 100 m 2 /g and can be as high as about 160 m 2 /g which is significantly greater than the specific surface area of γ-Al 2 O 3 known in the prior art.
Useful catalysts in accordance with the present invention may include the various constituents over a range of amounts, reported here as weight percentages of the catalyst carrier, excluding the later applied coatings. For example, iron (in the form of magnetite) will generally be present in an amount from 1 to 6 percent; cerium (in the form of cerium oxide) in an amount of greater than 1 percent, preferably 2 to 6 percent; rhenium in an amount from 0.02 to 0.1 percent; nickel in an amount from 3 to 40 percent, and platinum in an amount of at least 0.3 percent. The specific combination of components employed can be selected to optimize certain properties of resulting catalyst.
For example, the amount of magnetite influences the conversion temperature for CO and NO as summarized in Table 1. Based on this information, iron amounts of 1 to 6% are suitable, and iron amounts of about 2 to 5% are preferred.
TABLE 1______________________________________Influence of Fe concentration on theconversion temperature of CO and NO. (λ = 1).Fe, wt % of thecatalyst carrier T.sub.conv, NO °C. T.sub.conv. CO °C.______________________________________1 400-500 380-5002 320-400 320-4003 200-250 200-2505 250-300 250-3006 390-450 350-400______________________________________
The concentration of cerium oxide in the catalyst has a substantial effect on the conversion of CO. Thus, as shown in Table 2, increasing cerium oxide concentrations result in greater CO conversion. Preferably, the cerium level will be greater than 1% to achieve conversions of at least 50% of the CO, and more preferably at least 2%.
TABLE 2______________________________________Influence of Ce Concentration on CO ConversionCe, % wt of thecatalyst carrier CO, conversion %______________________________________0.5 481 552 703 754 855 81______________________________________
The use of barium additive BaReO 4 appreciably increases activity of the system during the conversion of NO x and eliminates use of costly rhodium. Furthermore, as shown in Table 3, optimum NO conversion is obtained when the Re to Pt ratio exceeds a mole ratio of about 1:1. Preferred mole ratios are in the range of from 1:1 to 5:1.
TABLE 3______________________________________Influence or the Re/Pt ratioon the conversion efficiency of NO.Re/Pt mole ratio NO, % conversion______________________________________0:1 60.440.5:1 78.281:1 90.422:1 91.235:1 88.45______________________________________
In forming the second layer, the amount of nickel also effects the CO conversion efficiency of the final catalyst. As shown in Table 4, increasing the amount of nickel results in increased CO conversion. Thus, the catalyst of the invention will preferably contain at least 10%, more preferably at least 25% nickel.
TABLE 4______________________________________Influence of Ni concentration on CO conversionNi, % wt of block CO, % conversion______________________________________1 523 755 8110 9015 9425 9930 9940 99______________________________________
The amount of nickel can be controlled by varying the duration of the heat treatment or by varying the amount of NiCl in the original solution. As shown in Table 5, application of an effective quantity of Ni can be achieved with heat treatments of about 2 to about 5 hours.
TABLE 5______________________________________Influence of the duration of heat treatment onNi concentration on the surface of carrier. Ni, % of catalyst carrier byTime (hours) weight______________________________________0.5 2-41 132 353 304 375 406 40______________________________________
A further factor in determining the amount of nickel in the catalyst is the temperature at which the heat treatment is conducted. As shown in Table 6, autocatalytic reduction reaction of Ni 2+ accelerates rapidly after 85° C.
TABLE 6______________________________________Influence of temperature reduction on Ni.sup.2+ reduction(t = 4 hours)T °C. Ni.sub.met , % conversion to metal______________________________________20 040 560 1275 3085 7595 95100 95______________________________________
Example 1
A honeycombed carrier of cordierite (Corning) of 75 mm length was coated by immersion in 1 liter of an aqueous solution containing 45.38 g Fe(NO 3 ) 3 , 40.75 g Ce(NO 3 ) 3 and 0.31 g BaReO 4 . Subsequently it was dried at 120° C. and heated for two hours at 600° C. In order to obtain Fe 3 O 4 and for the reduction of perrhenate to rhenium, the catalyst was heated in a reducing atmosphere of forming gas (N 2 :H 2 =90:10) for four hours at 550° C. to 600° C.
The dried carrier having the first layer applied was then immersed in an aqueous solution of NiCl 2 (25 g/l), dried for two hours at 120° C. and put into an autoclave, the inside surface of which is covered by a non-metallic material (for instance polyethylene, Teflon or other), in a 1-liter solution containing hydrazine (50 ml 70% N 2 H 4 , H 2 O), ammonium (250 ml 25% NH 4 OH) and thiocarbamide (1 g). The autoclave was hermetically sealed and slowly heated up to 90° C.-100° C. in one hour and then held at this temperature for five hours to convert the Ni 2+ to metallic nickel.
The autoclave treated carrier was then washed with water to remove residual Ni 2+ , dried for two hours at 120° C. and then coated with platinum. The platinum coating is applied over a two hours period in a non-hermetic vessel at 50° C.-60° C. by immersing the nickel coated carrier in a solution (1 l) containing 10 ml of H 2 PtCl 6 solution of 15 mg/ml concentration in water, 400 ml of 0.05M Trilon™, 300 ml of 25% NH 4 OH, 40 ml of 5% N 2 H 4 .
The resulting catalyst had a composition of 3% iron (in the form of magnetite), 4% cerium (in the form of cerium oxide), 0.025% rhenium, 25% nickel and 0.030% platinum and was an effective three-way conversion catalyst for treatment of exhaust gases when tested for ability of removing CO, NOx and HC from exhaust gas with λ=1 and n (of the engine)=3400 rev -1 .
Example 2
To evaluate the necessity of the autoclave treatment to the formation of the nickel coating, two catalysts were prepared having approximately the same composition. One was prepared in the autoclave as described in example 1, and had a specific surface area of around 160 m 2 /g. The other was prepared by saturating the carrier block with nickel solution, heating (but not autoclaving) and reducing the block under flowing hydrogen at 800° C. The comparison catalyst had a specific surface area of 60 to 80 m 2 /g. As shown in Table 7, while the catalyst prepared without use of the autoclave had catalytic activity, the example prepared using the autoclave was far superior.
TABLE 7______________________________________Influence of a Ni coating mode on theconversion efficiency of the catalystNi- Coating % conversionconcentration, % method CO HC NO______________________________________24 without 60 23 11 autoclave23.8 in 85 82 84 autoclave______________________________________
Example 3
The catalyst was prepared in the same manner as in Example 1, except that the amount of Fe(NO 3 ) 3 in the solution was 15.12 g. This resulted in a catalyst with an iron content of 1%.
Example 4
The catalyst was prepared in the same manner as in Example 1, except that the amount of Fe(NO 3 ) 3 in the solution was 30.2 g. This results in a catalyst with an iron content of 2%.
Example 5
The catalyst was prepared in the same manner as in Example 1, except that the amount of Fe(NO 3 ) 3 in the solution was 75.6 g. This results in a catalyst with an iron content of 5%.
Example 6
The catalyst was prepared in the same manner as in Example 1, except that the amount of Fe(NO 3 ) 3 in the solution was 121.0 g. This results in a catalyst with an iron content of 8%.
Example 7
The catalyst was prepared in the same manner as in Example 1, except that 5.1 g of Ce(NO 3 ) 3 was present in the solution. This resulted in a catalyst with a cerium content of 0.5%.
Example 8
The catalyst was prepared in the same manner as in Example 1, except that 10.2 g of Ce(NO 3 ) 3 was present in the solution. This resulted in a catalyst with a cerium content of 1%.
Example 9
The catalyst was prepared in the same manner as in Example 1, except that 10.4 g of Ce(NO 3 ) 3 was present in the solution. This resulted in a catalyst with a cerium content of 2%.
Example 10
The catalyst was prepared in the same manner as in Example 1, except that 15.5 g of Ce(NO 3 ) 3 was present in the solution. This resulted in a catalyst with a cerium content of 3%.
Example 11
The catalyst was prepared in the same manner as in Example 1, except that 25.9 g of Ce(NO 3 ) 3 was present in the solution. This resulted in a catalyst with a cerium content of 5%.
Example 12
The catalyst was prepared in the same manner as in Example 1, except that the barium perrhenate was omitted from the solution for forming the first layer.
Example 13
The catalyst was prepared in the same manner as in Example 1, except that the mole ratio of Re:Pt was adjusted to 0.5:1 by changing the amount of barium perrhenate used in forming the catalyst to 0.16 g.
Example 14
The catalyst was prepared in the same manner as in Example 1, except that the mole ratio of Re:Pt was adjusted to 2:1 by changing the amount of barium-perrhenate used in forming the catalyst to 0.62 g.
Example 15
The catalyst was prepared in the same manner as in Example 1, except that the mole ratio of Re:Pt was adjusted to 5:1 by changing the amount of barium perrhenate used in forming the catalyst to 1.55 g.
Example 16
The catalyst was prepared in the same manner as in Example 1, but the amount of NiCl in the solution was reduced to 1% to produce a catalyst having a nickel content of 1%.
Example 17
The catalyst was prepared in the same manner as in Example 1, but the amount of NiCl in the solution was reduced to 3% to produce a catalyst having a nickel content of 3%.
Example 18
The catalyst was prepared in the same manner as in Example 1, but the amount of NiCl in the solution was reduced to 5% to produce a catalyst having a nickel content of 5%.
Example 19
The catalyst was prepared in the same manner as in Example 1, but the amount of NiCl in the solution was reduced to 10% to produce a catalyst having a nickel content of 10%.
Example 20
The catalyst was prepared in the same manner as in Example 1, but the amount of NiCl in the solution was reduced to 15% to produce a catalyst having a nickel content of 15%.
Example 21
The catalyst was prepared in the same manner as in Example 1, but the amount of NiCl in the solution was reduced to 30% to produce a catalyst having a nickel content of 30%.
Example 22
The catalyst was prepared in the same manner as in Example 1, but the amount of NiCl in the solution was reduced to 40% to produce a catalyst having a nickel content of 40%. | A three-way conversion catalyst useful for the treatment of exhaust gas streams to accomplish the catalytic oxidation of carbon monoxide and hydrocarbons and the catalytic reduction of the oxides of nitrogen has a catalyst carrier such as cordierite coated with an oxygen reservoir layer, and a second layer of finely divided nickel needles obtained by reduction of Ni 2+ in an autoclave and a platinum group metal. | 8 |
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