description stringlengths 2.98k 3.35M | abstract stringlengths 94 10.6k | cpc int64 0 8 |
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BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to processing signal data and in particular relates to correcting clock phase offset while processing signal data.
[0003] 2. Description of the Prior Art
[0004] Clock path delay mismatch or clock phase offset is an important parameter in signal data processing and consequently in the design of signal data processors. As signal data processors become ever smaller (due to process shinking) and more complex, this parameter becomes a more significant problem faced by the designers of such signal data processors.
[0005] There are various reasons for the increasing significance of clock phase offset. Firstly as complementary metal-oxide-semiconductor (CMOS) minimum feature sizes become smaller, the mismatch between different clock buffers or different clock paths increases dramatically. It is known in the art that offset voltage is dependent upon the threshold voltage (V t ) mismatch and β mismatch. Although β mismatch contributes more with smaller feature sizes, in current mainstream CMOS technology, the V t mismatch is the dominant factor. The V t offset (V os ) can be calculated as the following equation:
[0000]
Vos
rms
=
Av
nwl
[0000] where V os is the RMS offset voltage,
[0006] Av is a process parameter,
[0007] n is the finger number, and
[0008] w and l are the MOSFET width and length respectively.
[0009] Although Av is improved slightly, in order to take advantage of the advanced CMOS technology, V os is still increasing due to smaller MOSFET size. For each buffer stage, the delay mismatch (ΔT d ) can be calculated as the following equation:
[0000]
Δ
Td
=
Vos
SR
[0000] where SR is the clock slew rate.
[0010] Assuming same clock rate and same slew rate design, ΔT d is proportional to Vos as shown in FIG. 1 . In this figure, threshold 1 is the switch point of a first clock buffer 1 and threshold 2 is the switch point of a second clock buffer 2 . Threshold 1 =threshold 2 +Vos due to the mismatch.
[0011] Secondly, due to the increased complexity of mixed signal circuit (high speed PHY) designs, clock distribution becomes more involved. Clocks need more buffers or more complicated clock trees to be delivered to their destinations, which increases the clock delay mismatch significantly.
[0012] Thirdly, higher data and clock rates make the situation even worse even with the same ΔT d design. The phase offset is proportional to the data rate, thus worsening as data rates increase.
[0013] According to the prior art the clock phase offset is corrected for in an initial calibration phase, e.g. during power up reset. This initial calibration can correct most of the clock phase offset. The present techniques recognise that later-arising temperature and/or power supply (e.g. low frequency power supply noise) induced offset can cause further offset to be introduced. Such factors become more significant as geometries decrease and may cause the clock offset to vary. Such dynamic variation in the clock offset can lead to levels of jitter that are problematic when signal data processing.
[0014] FIG. 2 schematically illustrates an arrangement for the generation of two clock signals in a receiver aligned with a received data stream in the prior art. A voltage controlled oscillator (VCO) 10 generates a single frequency clock locked to a reference clock. I/Q clock generation block 20 creates two clock signals (I clock and Q clock) with a 90 degree offset from one another. In order to align these clocks with the received data stream, each of the I/Q clocks is then passed to two phase interpolators (PIs) 30 and 40 . Phase interpolators 30 and 40 are controlled by the digital vector ctrl which is determined by the clock data recovery performed by clock data recovery unit 50 on the received data stream. Phase interpolators 30 and 40 then generate two new clocks iclk and qclk with 90 degree offset from one another, as well as aligned with the incoming data. The iclk and qclk clocks are then used to sample and recover the incoming signal data received by the apparatus. The calibration of this arrangement is provided by delay units 60 and 70 , the control values of which are set in registers R 1 and R 2 at an initial calibration phase prior to processing data.
[0015] A data receiver may alternatively generate iclk and qclk aligned with a stream of received data by means of phase locked loop (PLL) based clock generation. An example arrangement is schematically illustrated in FIG. 3 . Here a phase detector 100 receives the incoming data stream and passes phase information via a loop filter 110 to voltage controlled oscillator (VCO) 120 . The VCO provides a reference signal to I/Q clock generator 130 which generates iclk and qclk. The iclk and qclk are fed back to phase detector 100 , so that the loop is locked and so that iclk and qclk are aligned with the stream of received data. This arrangement could also be calibrated by delay units (not illustrated) at an initial calibration phase as discussed with reference to FIG. 2 .
[0016] Returning to the example arrangement of FIG. 2 , the phase interpolators, although perhaps initially calibrated by the delay units following them within the required tolerances, are recognised by the present techniques to suffer from various further impairments such as delay mismatch and integral non-linearity (INL). Because of this iclk and qclk not only suffer from static clock offset (e.g delay mismatch), but may also suffer from dynamically evolving clock offsets (e.g due to INL, temperature dependent delay mismatch or power supply dependent mismatch). The latter dynamic clock offsets are not addressed by power up reset or initial calibration, and as application speeds increase and process geometries decrease dynamic offset becomes one of the most significant limiting factors on coping with variations in clock phase offsets.
[0017] It is thus desirable to provide a method of processing signal data in which this dynamically arising clock offset is addressed.
SUMMARY OF THE INVENTION
[0018] According to a first aspect of the invention there is providing a method of processing signal data comprising the steps of:
[0019] generating a first clock signal and a second clock signal;
[0020] processing said signal data using said first clock signal and said second clock signal;
[0021] while processing said signal data, measuring a measured phase difference between said first clock signal and said second clock signal; and
[0022] adjusting a current phase offset of at least one of said first clock signal and said second clock signal in dependence upon said measured phase difference,
[0023] such that a target phase difference between said first clock signal and said second clock signal is maintained.
[0024] Whilst static offset can be corrected for by initial calibration, dynamic clock offsets which evolve during use of a signal data processing apparatus cannot. The present technique recognises and addresses this by continuously measuring the phase difference between the first and second clock signals and adjusting the current phase offset of at least one of those clock signals in dependence of the measured phase difference. In this way a target phase difference between the clock signals can be maintained, despite the evolution of dynamic clock offsets during the operation of the signal data processing apparatus. Hence account may be made for both static and dynamic sources of clock phase offset. Not only may initial clock offsets be calibrated for, but clock phase offset is monitored and corrected for in real time.
[0025] In one embodiment of the present invention the method further comprises an initial calibration step prior to processing said signal data of measuring an initial phase difference between said first clock signal and said second clock signal; and
[0026] presetting an initial phase offset of at least one of said first clock signal and said second clock signal in dependence of said initial phase clocks.
[0027] Whilst it is possible for all correction of clock phase offsets to be performed dynamically during normal operation of the signal data processing apparatus, an initial calibration step may advantageously be carried out to perform a static phase offset correction. Then only the dynamically evolving clock offsets need be corrected for by the continuous monitoring and correcting process.
[0028] The present invention may be employed to continuously correct clock offset in a range of signal data processing scenarios. In one embodiment the signal data is received signal data, whereas in another embodiment the signal data is signal data to be transmitted.
[0029] According to one embodiment the method further comprises the step of: generating at least one phase control signal in dependence upon said measured phase difference, said adjusting said current phase difference being controlled by said at least one phase control signal. Generating at least one phase control signal represents a convenient manner of signalling the necessary adjustment to be made to the current phase difference.
[0030] It will be appreciated by those skilled in the art that the adjustment of the current phase offset may be performed in a variety of ways. According to one embodiment adjusting said current phase offset is performed by at least one phase interpolator. According to another embodiment said adjusting said current phase offset is performed by at least one phase locked loop unit. According to yet another embodiment said adjusting said current phase offset is performed by at least one delay unit.
[0031] It will be appreciated that the phase control signal may be generated in a variety of ways, but in one embodiment the at least one phase control signals generated by a digital processing unit. The digital processing unit thus coordinates the at least one phase control signal and thus the necessary adjustment of the current clock phase offset. The at least one phase control signal may of course take a variety of forms. In one embodiment the at least one phase control signal is a digital control vector.
[0032] Whist in some embodiments the first and second clock signals are separately generated, in one embodiment a single clock signal is generated which is provided as both said first clock signal and said second clock signal whilst it is then necessary for the entire desired clock phase offset between the first and second clock signals to be generated by the adjustment of the current phase difference, this arrangement has the simplifying advantage of only a single clock signal needing to be generated. It will further be appreciated that whilst the target phase difference between the first and second clock signal could fall anywhere between 0 and 360 degrees, in one embodiment the target phase difference is 90 degrees.
[0033] In such an embodiment where the target phase difference is 90 degrees, the first clock signal may be defined as an I-clock and the second clock signal may be defined as a Q-clock. These “in phase” and “quadrature phase” clocks may then be used, for example, to sample and recover data from a received data stream.
[0034] In the situation where the signal data is received signal data, the received signal data may have a clock signal embedded in it and in one embodiment the first clock signal and/or second clock signal are aligned with a recovered clock signal recovered from the received signal data. It will be recognised that this alignment assists in the accurate signal data processing of that received signal data.
[0035] Whilst in some embodiments a phase control signal may be generated for each measured phase difference, in one embodiment generating said at least one phase control signal is performed in dependence upon a plurality of measured phase differences. In this way variations over time may be monitored and appropriately responded to.
[0036] According to a second aspect of the present invention there is provided a signal data processing apparatus comprising:
[0037] clock generating circuitry configured to generate a first clock signal and a second clock signal
[0038] processing circuitry responsive to said first clock signal and said second clock signal to process said signal data;
[0039] measuring circuitry operating while said processing circuitry processes said signal data to measure a measured phase difference between said first clock signal and said second clock signal; and
[0040] adjusting circuitry configured to adjust a current phase offset of at least one of said first clock signal and said second clock signal in dependence upon said measured phase difference,
[0041] such that a target phase difference between said first clock signal and said second clock signal is maintained.
[0042] According to a third aspect of the present invention there is provided a signal data processing apparatus comprising:
[0043] generating means for generating a first clock signal and a second clock signal
[0044] processing means for processing said signal data using said first clock signal and said second clock signal;
[0045] measuring means for, while processing said signal data, measuring a measured phase difference between said first clock signal and said second clock signal; and
[0046] adjusting means for adjusting a current phase offset of at least one of said first clock signal and said second clock signal in dependence upon said measured phase difference,
[0047] such that a target phase difference between said first clock signal and said second clock signal is maintained.
[0048] The above, and other objects, features and advantages of this invention will be apparent from the following detailed description of illustrative embodiments which is to be read in connection with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0049] FIG. 1 schematically illustrates the relationship between voltage offset and delay mismatch;
[0050] FIG. 2 schematically illustrates the generation of two statically calibrated clock signals using phase interpolators in the prior art;
[0051] FIG. 3 schematically illustrates the generation of two clock signals using a phase locked loop;
[0052] FIG. 4 schematically illustrates the generation of two dynamically calibrated clock signals according to a first example embodiment of the present invention;
[0053] FIG. 5 schematically illustrates the generation of two dynamically calibrated clock signals according to a second example embodiment of the present invention; and
[0054] FIG. 6 schematically illustrates the generation of two dynamically calibrated clock signals according to a third example embodiment of the present invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0055] FIG. 4 schematically illustrates a first example embodiment of the present invention in which a receiver generates two clock signals aligned with the clock signal in a received data stream. Voltage control oscillator (VCO) 200 generates a single frequency clock locked to a reference clock. This single frequency clock is passed to I/Q clock generation block 210 which creates two clocks with 90 degree offset from one another (I-clock and Q-clock). Note that in other embodiments it is also possible for the VCO to generate the I/Q clocks directly. The I and Q clocks are then passed to phase interpolators (PIs) 220 and 230 . From these inputs the two PIs create two new clocks, iclk and qclk, with 90 degree offset from one another, as well as aligned with the clock signal in the received data. The iclk and qclk clocks are then used to sample and recover incoming data.
[0056] The alignment of iclk and qclk with the clock signal in the received data occurs by means of clock data recovery unit 240 , which recovers the embedded clock signal from the received data, passing that clock data information to digital processing unit 250 . If no further dynamic adjustment of the clock signals is required (see below), then both PI 220 and PI 230 receive the same digital control signal ctrl (the same digital control signal as was described with reference to FIG. 2 ). In other words, ctrl 1 =ctrl and ctrl 2 =ctrl. As also described with reference to FIG. 2 , this steering of the PIs may be calibrated at startup, to account for static offset.
[0057] Meanwhile, phase sensor 260 also receives the clock signals iclk and qclk, and measures the phase difference between them. This phase offset information is then forwarded to digital processing unit 250 which then varies the digital control signal ctrl it sends to each PI, i.e. it generates two distinct control signals, ctrl 1 and ctrl 2 . Ctrl 1 is fed back to phase interpolator 120 and ctrl 2 is fed back to phase interpolator 130 . Any variation from the target phase difference (in this embodiment a 90 degree offset between iclk and qclk) is then immediately corrected for by virtue of the control signals ctrl 1 and ctrl 2 reaching phase interpolators 120 and 130 . In some embodiments it is possible for digital processing unit 250 to always leave one of the control signals at its “default” value of ctrl, and only to apply any timing adjustment (whether positive or negative) to the other control signal.
[0058] The apparatus schematically illustrated in FIG. 4 may also be used as a static clock offset correction circuit, for example as a power up reset calibration apparatus, whereby no separate calibration of ctrl is performed and an initial phase offset measurement by phase sensor 260 is made at startup dictating the initial values of ctrl 1 and ctrl 2 . Phase sensor 260 is then switched off during signal data processing operations of the apparatus and ctrl 1 and ctrl 2 only vary as ctrl would in order to align iclk and qclk with the received data.
[0059] Digital processing unit 250 may be arranged to compensate for both low frequency offset components as well as high frequency offset components depending upon the particular implementation. In the case of compensating for low frequency offset, the digital processing unit can gather a number of phase difference measurements from phase sensor 260 taken over a period of time to average out the high frequency variations.
[0060] FIG. 5 illustrates a second example embodiment of the present invention. In this embodiment voltage controller oscillator 300 , I/Q clock generator 310 and phase sensor 260 behave in the same manner as described for the equivalent components in FIG. 4 and are not described in further detail here. In this embodiment phase interpolators 320 and 330 are not controlled by digital processing unit 350 , but are steered by a single digital control vector ctrl. The digital control vector ctrl derives from clock data recovery unit 360 , which recovers the clock signal embedded in the received data stream. This enables PIs 320 and 330 to generate iclk and qclk aligned with the clock signal in the received data stream. In this embodiment iclk and qclk have a target phase difference of 90 degrees. Phase sensor 340 monitors iclk and qclk, measuring the phase difference between them and passing this information to digital processing unit 350 . The digital processing unit 350 creates control signals N 1 and N 2 which are passed back to delay units 370 and 380 . Delay units 370 and 380 are then steered by the control signals N 1 and N 2 respectively to apply any necessary phase offset correction to the iclk and qclk clock signals. It will be appreciated that delay units 370 and 380 must have sufficient delay variation to cover the possible range of offsets required. The maximum offsets required may be established by Monte Carlo simulation. In this embodiment the clock data recovery phase information (ctrl) has been separated from the dynamic phase offset information (N 1 and N 2 ). In the previous embodiment illustrated in FIG. 4 this information was combined, i.e. ctrl 1 =ctrl+N 1 and ctrl 2 =ctrl+N 2 .
[0061] In some applications no phase interpolators may be needed (for example, in a transmitter or in a PLL based data receiver such as that shown in FIG. 3 ) and in such a situation an arrangement such as that schematically illustrated in FIG. 6 may be employed. Two clock signals clk 1 and clk 2 are fed into delay units 400 and 410 respectively. Delay units 400 and 410 must then apply sufficient clock phase offset to generate the target phase clock phase difference between the clock signals iclk and qclk. The feedback system works as described with reference to FIG. 5 , in that phase sensor 420 measures the phase difference between iclk and qclk, passing this information to digital processing unit 430 which then generates control signals N 1 and N 2 which are fed back to delay units 400 and 410 respectively. Note that in this arrangement it is possible for clk 1 and clk 2 to in fact be the same clock signal, this being possible so long as delay units 400 and 410 have sufficient variability to generate the desired target phase difference between iclk and qclk.
[0062] Thus, according to the present technique, a dynamic correction of clock phase offset is enabled, in which the correction of the instantaneous clock phase offset is possible. By monitoring, tracking and correcting for clock phase offset in real time, greater accuracy is possible in the provision of phase matched clock signals both at the receiver and transmitter side. Consequently, jitter tolerance on the receiver side is improved and jitter generation on the transmitter side is lessened.
[0063] Although illustrative embodiments of the invention have been described in detail herein with reference to the accompanying drawings, it is to be understood that the invention is not limited to those precise embodiments, and that various changes and modifications can be effected therein by one skilled in the art without departing from the scope and spirit of the invention as defined by the appended claims. | The present invention provides a method of processing signal data comprising generating a first clock signal and a second clock signal and processing the signal data using the first clock signal and the second clock signal. While processing the signal data, the phase difference between the first clock signal and the second clock signal is measured and corrected for so that a target phase difference between the first clock signal and the second clock signal is maintained. | 7 |
This application is a continuation-in-part of U.S. patent application Ser. No. 10/858,213, filed Jun. 1, 2004, abandoned, which claims priority to U.S. Provisional Application Ser. No. 60/558,695, filed Apr. 1, 2004, which is herein incorporated by reference in its entirety.
FIELD OF THE INVENTION
The present invention relates to a self-locking panel nut fastener. In particular, the present invention relates to a nut for being received within an opening in a panel that self-locks and upon receiving a threaded screw or bolt enhances the locking relationship with the panel.
BACKGROUND
There are many situations in which panels have openings located inwardly of the edges to which it would be desirable to adhere other equipment or panels. A desirable means for accomplishing this would be the provision of a nut that could be readily positioned within the opening and self-lock on receiving a securing bolt or screw therein. This is especially desirable in those situations in which access is substantially confined to one side of the panel and where there is no easy means of tightening or otherwise securing or adjusting the nut position from the opposite side of the panel. These situations are frequently encountered, for example, in modern automotive vehicles.
U.S. Pat. No. 4,610,588 provides a fastener clip adapted for use with an associated fastener including a head portion having an aperture through which the fastener extends. Included in the fastener clip is a pair of integral, spaced apart legs extending from each side of the head portion. Each leg includes first and second portions with the second portion being bent back upon the first portion in a position spaced outwardly thereof. A finger portion is located at a free end of the second portion and extends inwardly toward and through an aperture in the first portion. When a tension load is imposed on the clip, connecting zones between the first and second portions of each leg are deflected toward each other to apply a clamping force to a fastener extending there between. A limitation with this fastener clip is that it is not configured for use with panel openings having uneven edges (e.g., burred edges, flanged edges).
U.S. Pat. No. 5,645,384 provides a release fastener with a first element providing a retention mechanism for engaging and retaining a stud of the fastener. A second element having a pair of flexible elongate components is spaced from the first by a bight portion and has a pair of transverse tabs disposed adjacent to the bight portion. These are adapted to engage one face of a support, in an aperture of which the receptacle is mounted. In use, the bight portion engages the other face. A third element is disposed at the opposite end of the second element from the bight portion and has a flexible barb portion arranged to flex on insertion of the receptacle in the aperture and to engage the other face after insertion in order to retain the receptacle in the aperture. A limitation with this release fastener is that upon insertion of a stud, the retention force is weak, and a general loosening of the device occurs over time.
U.S. Pat. No. 5,919,019 provides a nut for mounting into an opening located in the central part of a panel including a sleeve and resilient locking trips and panel edge securing means extending from opposite sides of the nut. When the nut is positioned within the opening the locking strips obstruct removal from the opening. On a bolt being fully received within the sleeve both the strips and edge securing means engage the panel. A limitation with this nut is that installation of the nut requires a high amount of insertion force.
U.S. Pat. No. 6,095,734 provides a push-nut fastener having a substantially planar base portion from which a cylindrical sleeve is drawn and internally threaded. A pair of angled leg portions extending from opposing lateral edges of the base portion, each including a laterally extending tab partially extending into a space formed between said leg portions for engaging threads of a mating male fastener. Inner and outer leg sections preferably define the leg portions. Each outer leg section includes an inwardly angled section that engages the edges of a mounting hole of a panel into which the push-nut is seated during assembly. A limitation with this fastener clip is that it is not configured for use with panel openings having uneven edges (e.g., burred edges, flanged edges).
What are needed are push-in nut fasteners configured for use with uneven panel opening edges. Additionally, what are needed are push-in nut fasteners with improved insertion ergonomics. Additionally, what are needed are improved push-in nut fasteners that do not loosen over time.
SUMMARY
The present invention relates to a self-locking panel nut fastener. In particular, the present invention relates to a nut for being received within an opening in a panel that self-locks and upon receiving a threaded screw or bolt enhances the locking relationship with the panel.
In certain embodiments, the present invention provides a push-in nut fastener, comprising a planar surface with proximal and distal ends; a sleeve extending from the planar surface; a cantilever integral with the planar surface and extending away from the planar surface distal end in a plane that is approximately parallel to and below the planar surface; and a retention arm integral with the planar surface and extending from the planar surface proximal end so that the retention arm is positioned at least partially beneath the sleeve.
In further embodiments, the sleeve comprises internal threads that receive a threaded fastener. In preferred embodiments, the sleeve is approximately perpendicular to the planar surface. In other embodiments, the push-in nut fastener is formed from sheet metal. In preferred embodiments, the sheet metal is spring steel. In further embodiments, the cantilever extends beyond the distal end of the planar surface. In even further embodiments, the retention arm is deflectable by a threaded fastener inserted into the sleeve.
In certain embodiments, the present invention provides a push-in nut fastener for insertion into a panel opening within a panel having upper and lower surfaces, the push-in nut comprising a planar surface having proximal and distal ends; a sleeve extending outwardly from the planar surface; a cantilever integral with and extending away from the planar surface distal end in a plane that is approximately parallel to and beneath the planar surface so that when the push-in nut fastener is inserted into the panel opening the cantilever engages the bottom surface of the panel and the planar surface engages the upper surface of the panel; and a retention arm integral with and extending away from the planar surface proximal end at an angle so that the retention arm is positioned at least partially beneath the sleeve so that when the push-in nut is inserted into the panel opening the retention arm engages the lower surface of the panel to secure the proximal end of the push-in nut fastener in the panel.
In further embodiments, the push-in nut is formed from sheet metal. In further embodiments, the sheet metal is spring steel. In yet further embodiments, the sleeve is approximately perpendicular to the planar surface. In preferred embodiments, the sleeve comprises internal threads that receive a threaded fastener. In further embodiments, the cantilever provides a leverage force against the lower surface of the panel upon insertion of the push-in nut fastener into the panel opening. In even further embodiments, the cantilever is curvilinear. In other preferred embodiments, the retention arm extends toward the planar surface distal end. In further embodiments, the retention arm is deflectable by a threaded fastener inserted into the sleeve. In yet further embodiments, deflection of the retention arm increases the angle between the planar surface and the retention arm.
In certain embodiments, the present invention provides a push-in nut fastener for insertion into a panel opening within a panel having upper and lower surfaces, the push-in nut comprising a planar surface with proximal and distal ends, wherein the planar surface contacts the upper surface of the panel to prevent the push-in nut fastener from being displaced through the panel opening; a sleeve extending outwardly from the planar surface, wherein the sleeve comprises internal threads to secure the threaded fastener; a cantilever integral with and extending away from the planar surface in a plane that is approximately parallel to and below the planar surface so that the cantilever extends beyond the planar surface distal end; and a retention arm integral with and extending away from the planar surface proximal end at an angle to a position at least partially below the sleeve, wherein upon insertion of the push-in nut fastener into the panel opening the planar surface engages the upper surface of the panel and the cantilever engages the bottom surface of the panel and thereby providing leverage for insertion of the proximal end of the push-in nut fastener and the retention arm into the panel opening so that the retention arm engages the lower surface of the panel and wherein the retention arm is deflectable by a threaded fastener inserted into the sleeve so that the retention arm exerts pressure against the threaded fastener and the lower surface of the panel.
In certain embodiments, the present invention provides a push-in nut fastener, comprising a planar surface with proximal and distal ends; a sleeve extending from the planar surface; a cantilever integral with the planar surface and extending away from the planar surface distal end in a plane that is approximately parallel to and below the planar surface; and a retention arm integral with the planar surface and extending from the planar surface proximal end so that the retention arm is positioned at least partially beneath the sleeve.
In further embodiments, the sleeve comprises internal threads that receive a threaded fastener. In preferred embodiments, the sleeve is approximately perpendicular to the planar surface. In other embodiments, the push-in nut fastener is formed from sheet metal. In preferred embodiments, the sheet metal is spring steel. In further embodiments, the cantilever extends beyond the distal end of the planar surface. In even further embodiments, the retention arm is deflectable by a threaded fastener inserted into the sleeve.
In further embodiments, the planar surface is molded with a plastisol pad. In preferred embodiments, the planar surface has therein at least one strengthening rib.
In certain embodiments, the present invention provides a push-in nut fastener, comprising a planar surface with proximal and distal ends; a sleeve extending from the planar surface, the sleeve having an axis extending through a center thereof and substantially perpendicular to the planar surface; a cantilever integral with the planar surface; a retention arm having a retention arm tail, the retention arm integral with the planar surface and extending from the planar surface proximal end so that the retention arm is positioned at least partially beneath the sleeve, such that at least a portion of the retention arm extends across the axis, the retention arm further comprising a retention arm tail flap extending from the retention arm tail; wherein upon insertion of the push-in nut fastener into an opening the retention arm tail flap engages the edge of the panel opening.
In preferred embodiments, the planar surface is molded with a plastisol pad. In preferred embodiments, the planar surface having therein at least one strengthening rib.
In preferred embodiments, the sleeve comprises internal threads that receive a threaded fastener. In other preferred embodiments, the sleeve is approximately perpendicular to the planar surface.
In preferred embodiments, the push-in nut fastener is formed from sheet metal. In other preferred embodiments, the sheet metal is spring steel.
In preferred embodiments, the cantilever extends beyond the distal end of the planar surface. In other preferred embodiments, the retention arm is deflectable by a threaded fastener inserted into the sleeve. In preferred embodiments, the engaging of the retention arm tail flap with the opening prevents rattling of the push-in nut fastener.
FIGURE DESCRIPTION
FIG. 1 illustrates a side overhead view of a push-in nut fastener embodiment.
FIG. 2 illustrates an overhead view of a panel.
FIG. 3 illustrates a side overhead view of a push-in nut fastener embodiment secured within a panel.
FIG. 4 illustrates a cross sectional side view of a push-in nut fastener embodiment.
FIG. 5 illustrates a side view of a threaded fastener in a push-in nut fastener embodiment secured within a panel.
FIG. 6 illustrates a cross sectional side view of a push-in nut fastener embodiment.
FIG. 7 illustrates a side view of a threaded fastener in a push-in nut fastener embodiment secured within a panel.
FIG. 8 illustrates an overhead view of a push-in nut fastener embodiment.
FIG. 9 illustrates a side overhead view of a push-in nut fastener embodiment.
FIG. 10 illustrates an overhead view of a push-in nut fastener embodiment.
FIG. 11 illustrates a push-in nut fastener embodiment from a bottom up perspective.
FIG. 12 illustrates a side view of a push-in nut fastener embodiment.
FIG. 13 illustrates a side view of a threaded fastener within a push-in nut fastener secured in a panel opening.
DETAILED DESCRIPTION
The following discussion relates to a push-in nut fastener in accordance with certain preferred embodiments of the present invention. The push-in nut fasteners of the present invention have numerous advantages over previous prior art devices including, but not limited to, an ability to cover a larger panel thickness range in comparison to typical designs, improved installation ergonomics, improved use with burred or flanged panel opening edges, decreased potential for rattling, and improved strength of the device. FIGS. 1-13 illustrate various preferred embodiments of the push-in nut fasteners of the present invention. The present invention is not limited to these particular embodiments.
Referring to FIG. 1 , the push-in nut fastener 100 comprises a planar surface 120 , a sleeve 130 , a cantilever 140 , and a retention arm 150 . The push-in nut fastener 100 is not limited to a particular material composition (e.g., steel, wood, plastic, or mixture thereof). In preferred embodiments, the material composition of the push-in nut 100 is sheet metal (e.g., steel). In particularly preferred embodiments, the composition of the push-in nut 100 is spring steel.
FIG. 2 generally presents a panel 160 (e.g., workpieces) designed for use with the present invention. Panels 160 finding use within the present invention have a panel opening 170 therein with a panel opening proximal end 180 and a panel opening distal end 190 . A panel 160 has a panel upper surface 200 and a panel lower surface 210 . Additionally, the panel 160 and panel opening 170 are located in a panel plane 220 .
FIG. 3 illustrates a push-in nut fastener 100 secured with a panel 160 . In particular, the push-in nut fastener 100 is insertable into the panel opening 170 with the sleeve 130 , cantilever 140 , and retention arm 150 fitting within the panel opening 170 and the planar surface 120 located above the panel opening 170 and panel plane 220 .
Referring again to FIG. 1 , the push-in nut fastener 100 comprises a planar surface 120 . The planar surface 120 comprises a planar surface distal end 230 and a planar surface proximal end 240 . The planar surface 120 is not limited to a particular shape (e.g., rectangular, square, circular). In preferred embodiments, the planar surface 120 is square shaped. The planar surface 120 is not limited to particular size dimensions. Additionally, the planar surface 120 has a planar surface plane 250 .
Referring to FIG. 3 , the planar surface 120 serves as a platform for securing the push-in nut fastener 100 with a panel 160 . In preferred embodiments, the size dimensions of the planar surface 120 are large enough to prevent the push-in nut fastener 100 from falling through a panel opening 170 . In such embodiments, the planar surface distal end 230 and planar surface proximal end 240 overlap the panel opening proximal end 180 and panel opening distal end 190 thereby preventing the push-in nut fastener 100 from falling through the panel opening 170 . Additionally, upon insertion of a push-in nut fastener 100 into a panel opening 170 , the planar surface plane 250 is in substantially parallel alignment with the panel plane 220 .
Referring to FIG. 1 , the push-in nut fastener 100 comprises a sleeve 130 . The sleeve 130 has a sleeve opening 260 . The sleeve opening 260 is not limited to a particular positioning within the push-in nut fastener 100 . In preferred embodiments, the sleeve opening 260 extends through the planar surface 120 . In preferred embodiments, the sleeve 130 is positioned at the center of the planar surface 120 . In further preferred embodiments, the sleeve opening 260 extends through the bottom of the planar surface 120 . The sleeve 130 is not limited to particular size dimensions. In preferred embodiments, the sleeve 130 is either drawn or roll-formed.
Still referring to FIG. 1 , the sleeve 130 has a sleeve axis 270 . In preferred embodiments, the sleeve axis 270 is in substantially perpendicular alignment with the planar surface plane 250 . FIG. 4 presents a cross sectional side view of a push-in nut fastener 100 and illustrates that the sleeve axis 270 is in substantially perpendicular alignment with the planar surface plane 250 . Referring to FIG. 3 , upon insertion of a push-in nut fastener 100 into a panel opening 170 , the sleeve axis 270 is in substantially perpendicular alignment with the planar surface plane 250 and the panel plane 220 .
FIG. 5 illustrates a side view of a threaded fastener 110 secured within a push-in nut fastener 100 secured in a panel opening 170 . Threaded fasteners 110 refer to hardware agents comprising a threaded face and a head. Examples include, but are not limited to, threaded workpieces, nuts, screws, set screws, grub screws, threaded bolts, and the like. The sleeve 130 serves to secure threaded fasteners 110 within the push-in nut fastener 100 . The sleeve 130 is not limited to securing a particular type of threaded fastener (e.g., threaded workpieces, nuts, screws, set screws, grub screws, threaded bolts). In preferred embodiments, a threaded fastener 110 is twisted down through the sleeve opening 260 .
Referring to FIG. 1 , the push-in nut fastener 100 comprises a cantilever 140 extending from the planar surface 120 . The cantilever 140 is not limited to a particular positioning on the push-in nut fastener 100 . In preferred embodiments, the cantilever 140 is positioned at the planar surface distal end 230 . Referring to FIG. 3 , upon insertion of a push-in nut fastener 100 in a panel opening 170 , the cantilever 140 fits into the panel opening 170 .
Referring to FIG. 4 , the cantilever 140 comprises a cantilever downwardly extending member 280 , and a cantilever horizontal member 290 extending from the cantilever downwardly extending member 280 . The cantilever downwardly extending member 280 extends downward from the planar surface distal end 230 at a predetermined angle (e.g., 0-degrees, 10-degrees, 45-degrees, 90-degrees, 120-degrees). In preferred embodiments, the cantilever downwardly extending member 280 extends downward from the planar surface distal end 230 at approximately a 90-degree angle. The cantilever downwardly extending member 280 is not limited to particular size dimensions.
Referring to FIG. 4 , the cantilever 140 further comprises a cantilever downwardly extending member plane 300 . In preferred embodiments, the cantilever downwardly extending member plane 300 is in approximately perpendicular alignment with the planar surface plane 250 . Referring to FIG. 5 , upon insertion of a threaded fastener 110 within a push-in nut fastener 100 secured within a panel 160 , the cantilever downwardly extending member plane 300 is in approximately perpendicular alignment with the planar surface plane 250 and the panel plane 220 .
Referring to FIG. 4 , the cantilever horizontal member 290 extends from the cantilever downwardly extending member 280 at a predetermined angle (e.g., 0-degrees, 10-degrees, 45-degrees, 90-degrees, 120-degrees). In preferred embodiments, the cantilever horizontal member 290 extends from the cantilever downwardly extending member 280 at approximately a 90-degree angle. In preferred embodiments, the cantilever horizontal member 290 extends from the cantilever downwardly extending member 280 in a proximal to distal direction. In other preferred embodiments, as shown in FIG. 6 , the cantilever horizontal member 290 extends from the cantilever downwardly extending member 280 at approximately a 45-degree angle. In such preferred embodiments, the cantilever horizontal member 290 extends from the cantilever downwardly extending member 280 in a proximal to distal direction.
Referring to FIGS. 4 and 6 , in particularly preferred embodiments, the length of the cantilever horizontal member 290 extends beyond the length of the planar surface distal end 230 . In such embodiments, the cantilever horizontal member 290 is not limited to a particular distance extension beyond the planar surface distal end 230 .
The cantilever horizontal member 290 is not limited to particular size dimensions. As shown in FIG. 4 , in some preferred embodiments, the cantilever horizontal member 290 is shaped in a linear fashion. As shown in FIG. 6 , in some preferred embodiments, the cantilever horizontal member 290 is shaped in a curvilinear fashion. In such embodiments, a cantilever horizontal member 290 shaped in a curvilinear fashion secures panel openings 170 with protruding rims (discussed in more detail below).
Referring to FIG. 4 , the cantilever 140 further comprises a horizontal member plane 310 . In some preferred embodiments, the cantilever horizontal member plane 310 is in approximately parallel alignment with the planar surface plane 250 , and in approximately perpendicular alignment with the cantilever downwardly extending member plane 300 . As shown in FIG. 6 , in other preferred embodiments, the cantilever horizontal member plane 310 is in approximately a 45-degree angle alignment with the planar surface plane 250 , and in approximately a 45-degree angle alignment with the cantilever downwardly extending member plane 300 .
Referring to FIG. 5 , in some preferred embodiments, upon insertion of a threaded fastener 110 in a push-in nut fastener 100 secured within a panel opening 170 , the cantilever horizontal member plane 310 is in approximately parallel alignment with the planar surface plane 250 and the panel plane 220 , and in approximately perpendicular alignment with the cantilever downwardly extending member plane 300 .
In other preferred embodiments, as shown in FIG. 7 , upon insertion of a threaded fastener 110 in a push-in nut fastener 100 secured within a panel opening 170 , the cantilever horizontal plane 310 is in approximately a 45-degree angle alignment with the planar surface plane 250 and the panel plane 220 , and in approximately a 45-degree angle alignment with the cantilever downwardly extending member plane 300 .
Referring to FIG. 5 , a linearly shaped cantilever horizontal member 290 secures push-in nut fasteners 100 with even edged panel openings 170 . In such preferred embodiments, the panel 160 fits between the cantilever horizontal member 290 and the planar surface distal end 230 . Referring to FIG. 7 , a curvilinearly shaped cantilever horizontal member 290 secures push-in nut fasteners 100 in panel openings 170 with protruding rim (e.g., uneven panel opening edges, burred edges, flanged edges). In such preferred embodiments, the protruding rim of a panel opening 170 fits against the cantilever downwardly extending member 280 and against the distal end of the cantilever horizontal member 290 . As such, the curvilinear shaped cantilever horizontal member 290 accommodates panel openings 170 with protruding rims.
Referring to FIGS. 5 and 7 , the cantilever 140 provides a leverage force as the push-in nut fastener 100 is inserted into a panel opening 170 . In particular, insertion of the push-in nut fastener 100 into the panel opening 170 requires placement of the planar surface 120 over the panel opening 170 and placement of the cantilever 140 underneath the panel opening distal end 190 . As the push-in nut fastener 100 is inserted into the panel opening 170 , the retention arm 140 is lowered through panel opening proximal end 180 (as discussed in more detail below). The cantilever 140 provides a leverage force against the panel lower surface 164 as the push-in nut fastener 100 is inserted into the panel opening 170 .
Referring to FIG. 1 , the push-in nut fastener 100 comprises a retention arm 150 . The retention arm 150 comprises a retention arm proximal flap 320 with a retention arm proximal flap distal end 330 , a retention arm distal flap 340 with a retention arm distal flap distal end 350 , and a retention arm tail 360 with a retention arm tail distal end 370 . The retention arm 150 further comprises a retention arm plane 400 .
Referring to FIG. 4 , the retention arm proximal flap 320 extends downward from the planar surface proximal end 240 at a predetermined angle (e.g., 0-degrees, 10-degrees, 45-degrees, 90-degrees, 120-degrees). In preferred embodiments, the retention arm proximal flap 320 extends downward from the planar surface proximal end 240 at approximately a 45-degree angle. In preferred embodiments, the direction of retention arm proximal flap 320 extension is from the planar surface proximal end 240 toward the proximal surface distal end 230 . The retention arm proximal flap 320 is not limited to particular size dimensions. As shown in FIG. 1 , in some preferred embodiments, the retention arm proximal flap 320 has a retention arm proximal flap opening 380 . In such preferred embodiments, the retention arm tail 360 is positioned within the retention arm proximal flap opening 380 (discussed in more detail below).
Referring to FIG. 4 , in particularly preferred embodiments, the retention arm proximal flap 320 extends beneath the sleeve 130 . FIG. 8 provides an overhead perspective of the retention arm proximal flap 320 extending beneath the sleeve 130 . Referring to FIG. 5 , upon insertion of a threaded fastener 110 into a push-in nut fastener 100 secured within a panel 160 , the retention arm 150 is deflected upon the panel lower surface 180 . Deflection of the retention arm 150 upon the panel lower surface 180 increases the securing of the push-in nut fastener 100 with the panel 160 (discussed in more detail below).
Referring to FIG. 1 , the retention arm distal flap 340 extends from the retention arm proximal flap distal end 330 at a predetermined angle (e.g., 0-degrees, 10-degrees, 45-degrees, 90-degrees, 120-degrees). In preferred embodiments, the retention arm distal flap 290 extends from the retention arm proximal flap distal end 330 at approximately a 20-degree angle. The direction of retention arm distal flap 340 extension is toward the planar surface proximal end 240 . The retention arm distal flap 290 is not limited to particular size dimensions. FIG. 4 provides a cross section side view of a push-in nut fastener with a retention arm proximal distal flap 340 extending from the retention arm proximal flap distal end 330 at approximately a 20-degree angle. FIG. 5 provides a side view of a threaded fastener 110 in a push-in nut fastener 100 secured within a panel 160 with a retention arm proximal distal flap 340 extending from the retention arm proximal flap distal end 330 at approximately a 20-degree angle.
Referring to FIG. 1 , the retention arm tail 360 extends from the retention arm distal flap distal end 350 at a predetermined angle (e.g., 0-degrees, 10-degrees, 45-degrees, 90-degrees, 120-degrees). The retention arm tail 360 is not limited to particular size dimensions. As shown in FIG. 1 , in some preferred embodiments, the retention arm tail 360 extends from the retention arm distal flap distal end 350 at approximately a 45-degree angle. In such preferred embodiments, the retention arm tail 360 extends through the retention arm proximal flap opening 380 . Referring to FIG. 5 , upon insertion of a threaded fastener 110 into a push-in nut fastener 100 secured within a panel opening 170 , the retention arm tail 360 extending through the proximal flap opening 380 is in contact with the panel lower surface 180 . Contacting the panel lower surface 180 with the retention arm tail 360 increases the securing of the push-in nut fastener 100 with the panel 160 (discussed in more detail below).
As shown in FIG. 9 , in other preferred embodiments, the retention arm tail 360 extends from the retention arm distal flap distal end 350 at approximately a 90-degree angle in a direction toward the planar surface 120 . In some preferred embodiments, the retention arm tail 360 comprises a retention arm tail flap 390 extending from the retention arm tail distal end 370 at a predetermined angle (e.g., 0-degrees, 10-degrees, 45-degrees, 90-degrees, 120-degrees). In preferred embodiments, the retention arm tail flap 390 extends from the retention arm tail distal end 370 at a 90-degree angle. FIG. 10 illustrates an overhead perspective of the retention arm tail flap 390 . The retention arm tail flap 390 is not limited to particular size dimensions. Referring to FIG. 7 , upon insertion of a threaded fastener 110 into a push-in nut fastener 100 secured within a panel opening 170 , the retention arm tail flap 390 is in contact with the panel lower surface 180 . Contacting the panel lower surface 180 with the retention arm tail flap 390 increases the securing of the push-in nut fastener 100 with the panel 160 . Additionally, contacting the panel lower surface 180 with the retention arm tail flap 390 permits push-in nut fasteners 100 to be secured with panel openings 170 with protruding rims (discussed in more detail below).
Referring to FIG. 1 , the retention arm 150 has a retention arm plane 400 . Referring to FIG. 5 , upon insertion of the push-in nut fastener 100 with the panel opening 170 , the retention arm plane 400 is located beneath the planar surface plane 250 and the panel plane 220 . In particular, the retention arm plane 400 is in an approximately diagonal alignment (e.g., 45-degree angle) with the planar surface plane 250 and the panel plane 220 .
In some preferred embodiments, as shown in FIG. 5 , the retention arm 150 provides a deflection force as a threaded fastener 110 is inserted into a push-in nut fastener 100 secured in a panel opening 170 . In particular, a threaded fastener 110 advancing through the sleeve 130 contacts the distal end of the retention arm 150 causing the retention arm 150 to deflect away from the threaded fastener 110 . Deflection of the retention arm 150 causes an increase in the angle between the planar surface proximal end 240 and the retention arm 150 . Additionally, deflection of the retention arm 150 causes the retention arm tail 360 to contact the panel lower surface 180 . In particular, as the retention arm 150 is deflected away from the threaded fastener 110 , the retention arm tail 360 contacts the panel opening proximal end 180 with a constant tension. As such, deflection of the retention arm 150 results in an increased securing of the push-in nut fastener 100 with the panel 160 . The constant contact tension between the retention arm 150 and the panel opening proximal end 180 prevents loosening of the fit between the push-in nut fastener 100 and the panel 160 over time.
In other preferred embodiments, as shown in FIG. 7 , the retention arm 150 provides a deflection force as a threaded fastener 110 is inserted into a push-in nut fastener 100 secured in a panel opening 170 . In particular, a threaded fastener 110 advancing through the sleeve 130 contacts the distal end of the retention arm 150 causing the retention arm 150 to deflect away from the threaded fastener 110 . Deflection of the retention arm 150 causes an increase in the angle between the planar surface proximal end 240 and the retention arm 150 . Additionally, deflection of the retention arm 150 causes the retention arm tail flap 390 to contact the panel lower surface 180 . In particular, as the retention arm 150 is deflected away from the threaded fastener 110 , the retention arm tail flap 390 contacts the panel opening proximal end 180 with a constant tension. As such, deflection of the retention arm 150 results in an increased securing of the push-in nut fastener 100 with the panel 160 . The constant contact tension between the retention arm 150 and the panel opening proximal end 180 prevents loosening of the fit between the push-in nut fastener 100 and the panel 160 over time. Additionally, securing the retention arm 150 with the retention arm tail flap 390 , as opposed to the retention arm tail 360 , provides a gap between the retention arm proximal flap 320 and the retention arm tail 360 . The protruding rim of a panel opening 170 fits within the gap between the retention arm proximal flap 320 and the retention arm tail 360 . As such, in preferred embodiments, the push-in nut fastener 100 is secured within panel openings 170 with protruding rims.
FIG. 11 illustrates a bottom view of a push-in nut fastener embodiment. As shown, the push-in nut fastener 100 comprises a planar surface 120 comprising a planar surface distal end 230 and a planar surface proximal end 240 , a sleeve 130 comprising a sleeve opening 260 and a sleeve axis 270 , a cantilever 140 comprising a cantilever downwardly extending member 280 , a cantilever horizontal member 290 , a cantilever downwardly extending member plane 300 , a horizontal member plane 310 , a retention arm 150 comprising a retention arm proximal flap 320 , a retention arm proximal flap distal end 330 , a retention arm distal flap 340 , a retention arm distal flap distal end 350 , a retention arm tail 360 , a retention arm tail distal end 370 , and a retention arm plane 400 .
Still referring to FIG. 11 , the planar surface 120 further comprises a planar surface bottom surface 410 . The planar surface bottom surface 410 comprises at least one strength rib 420 (e.g., a set of stiffening beads). The present invention is not limited to a particular type of strengthening ribs 420 . The strengthening ribs 420 are not limited to a particular length or width. In some embodiments, a set of strength ribs 420 may be positioned at any location along the planar surface bottom surface 410 . In preferred embodiments, two sets of strength ribs 420 are laterally positioned along the planar surface bottom surface 410 on each side of the sleeve 130 such that each set of strength ribs 420 extends from the planar surface distal end 230 to the planar surface proximal end 240 . Upon insertion of the push-in nut fastener 100 into a panel, the strengthening ribs 420 function to maintain the integrity of the push-in nut fastener 100 as a whole (e.g., function to prevent the planar surface 120 from bowing).
FIG. 12 illustrates a side view of a push-in nut fastener embodiment. As shown, the push-in nut fastener 100 comprises a sleeve 130 comprising a sleeve opening 260 and a sleeve axis 270 , a cantilever 140 comprising a cantilever downwardly extending member 280 , a cantilever horizontal member 290 , a cantilever downwardly extending member plane 300 , a horizontal member plane 310 , a retention arm 150 comprising a retention arm proximal flap 320 , a retention arm proximal flap distal end 330 , a retention arm distal flap 340 , a retention arm distal flap distal end 350 , a retention arm tail 360 , a retention arm tail distal end 370 , a retention arm tail flap 390 , and a retention arm plane 400 .
Still referring to FIG. 12 , a panel padding 430 encompasses the upper and lower surfaces of the planar surface planar surface including the planar surface distal end, planar surface proximal end, planar surface plane, and the planar surface bottom surface. The panel padding 430 is not limited to a particular material (e.g., plastic, rubber, foam, or mixture thereof). In preferred embodiments, the material of the panel padding 430 is plastisol. The panel padding 430 is not limited to particular size dimensions. In preferred embodiments, the panel padding 430 extends beyond the planar surface proximal end and above the retention arm tail flap 390 . In preferred embodiments, the panel padding 430 is molded upon the planar surface such that the sleeve opening 260 remains exposed.
FIG. 13 illustrates a side view of a threaded fastener within a push-in nut fastener secured in a panel opening. As shown, the push-in nut fastener 100 comprises a panel padding 430 encompassing the upper and lower surfaces of the planar surface planar surface including the planar surface distal end, planar surface proximal end, planar surface plane, and the planar surface bottom surface, a sleeve 130 comprising a sleeve opening 260 and a sleeve axis 270 , a cantilever 140 comprising a cantilever downwardly extending member 280 , a cantilever horizontal member 290 , a cantilever downwardly extending member plane 300 , a horizontal member plane 310 , a retention arm 150 comprising a retention arm proximal flap 320 , a retention arm proximal flap distal end 330 , a retention arm distal flap 340 , a retention arm distal flap distal end 350 , a retention arm tail 360 , a retention arm tail distal end 370 , a retention arm tail flap 390 , and a retention arm plane 400 .
Still referring to FIG. 13 , upon insertion of a threaded fastener 110 , the panel padding 430 is positioned between the panel 170 and the head of the threaded fastener 110 such that the head of the threaded fastener 110 is prevented from contacting the panel 170 . As such, in preferred embodiments, the panel padding 430 raises the head of the threaded fastener 110 off of the panel 170 . In preferred embodiments, the positioning of the panel padding 430 serves to provide a watertight seal between the threaded fastener 110 and the panel 170 . In preferred embodiments, the positioning of the panel padding 430 serves to dampen potential rattling sound between the threaded fastener 110 and the panel 170 .
Still referring to FIG. 13 , in preferred embodiments, the panel padding 430 further engages the retention arm flap 390 positioned at the edge of the panel opening 170 . As such, the panel padding 430 serves to secure the retention arm flap 390 with the edge of the panel opening 170 (e.g., serves to prevent the retention arm flap 390 from snapping beneath the panel opening 170 ). By preventing the retention arm flap 390 from snapping beneath the edge of the panel opening 170 , the push-in nut fastener 100 may be used in panels with very thin thickness measurements (described in more detail below).
Still referring to FIG. 13 , in preferred embodiments, securing the retention arm flap 390 with the edge of the panel opening 170 provides a compression force within the retention arm distal flap 340 so as to prevent rattling of the push-in nut fastener 100 in the absence of an inserted threaded fastener 110 . Additionally, in preferred embodiments, securing the retention arm flap 390 within the edge of the panel opening 170 provides improved pull out performance of the push-in nut fastener 100 .
Still referring to FIG. 13 , upon insertion of a threaded fastener 110 , the panel padding 430 the positioning of the panel padding 430 permits the push-in nut fastener 100 to be secured within a panel 170 having sections of varied thickness (e.g., panel thickness ranges between 0.7 mm to 1.8 mm). As such, in preferred embodiments, push-in nut fasteners 100 comprising a panel padding 430 are especially applicable for use in panels 170 having varied thickness sections (e.g., a door panel having a section with a thickness of 0.70 mm and a thickness of 1.8 mm in a different section; “tailor welding”).
All publications and patents mentioned in the above specification are herein incorporated by reference. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. Indeed, various modifications of the described modes for carrying out the invention that are obvious to those skilled in the relevant fields are intended to be within the scope of the following claims. | A self-locking panel nut fastener having a nut for being received within an opening in a panel which self-locks and upon receiving a threaded screw or bolt enhances the locking relationship with the panel. | 5 |
BACKGROUND OF THE INVENTION
1. Technical Field
This invention relates to an apparatus and method for testing load bearing capacity on a pile or group of piles. In one aspect, this invention relates to novel apparatus and method for testing load bearing capacity on a pile or group of piles, utilizing a reaction anchor apparatus and method.
2. Background
In the construction industry, various types and shapes of piles are utilized for constructing foundations on the piles. These foundations are the structural supports upon which many types of constructions are built. Foundations support the loads imposed upon them and, hence, the loads imposed upon the piles, by such constructions as high rise buildings, power plants, river dams, and many other constructions.
Among the most common types and shapes of piles are timber piles, steel pipe piles, H-Piles, L-Piles, precast concrete piles, and cast-in-place concrete piles. These piles are in-stalled vertically or battered at an angle.
Piles are forced deep down into the soil by repetitive blows on their tops. These powerful blows are provided by pile-driving machines, also known as hydraulic hammers. Piles also can be poured-in, i.e., cast-in-place, by drilling a deep hole in the soil, then filling it with concrete. Generally, reinforcement steel rods, also known as rebar, are introduced into the hole prior to filling it with concrete.
The most commonly used method of installation of piles is by beating them down into the ground by means of a pile-driving machine.
Through the years, the construction industry has developed apparatus and testing methods for determining the capability of a vertical pile, a batter pile, or a group of piles to resist a required level of static compression loads as actually applied on the pile or group of piles. These testing methods determine whether a pile or group of piles has adequate bearing capacity or not.
Testing methods have been standardized by the American Society for testing materials, also known as ASTM. The Standard Test Method For Piles Under Static Axial Compressive Load, designation D1143-81, (reapproved 1987) covers pile testing utilizing conventional apparatus and methods for determining the capability of piles to resist a static compression load as actually applied on the piles.
INTRODUCTION TO THE INVENTION
According to ASTM D1143-81, single piles must be tested to 200% of the anticipated design load, while pile groups must be tested to 150% of the group design load.
Conventionally, for testing an individual pile, two additional piles have to be installed, using the same method and equipment utilized for installing the pile under test. These additional piles are driven into the soil on two diametrically opposing sides of the pile to be tested and at not less than seven feet from the pile being tested. These additional piles are known in the trade as anchor piles.
A test beam then is installed across the tops of the anchor piles, tying them to the beam and above the pile under test, forming what is known in the trade as a reaction frame. This test beam is set on a hydraulic jack, which in turn is set on top of the pile under test.
Upward hydraulic push is applied by the jack against the beam. The beam cannot move up because it is tied onto the anchor piles. As a result, the hydraulic power, i.e., the force exerted by the hydraulic jack, is applied downwardly against the top of the pile under test. These forces are applied incrementally, increasing at pre-established time intervals and held then at the maximum predetermined test loading for a specified length of time.
Certain instrumentation is utilized for determining the axial loading and for determining any movements, e.g., axial, rotational, and lateral, of the pile under test.
If the test proves the capability of the pile to resist the specified axially applied compressive loading, and if there are no other deviations beyond acceptable standards, then that pile is determined to be fit to be used for its intended purposes, i.e., it has adequate bearing capacity.
Testing a group of piles instead of a single pile utilizes the same procedure, but in the case of a group of piles, the various piles in the group are capped by a common cap, and the test load is applied uniformly upon the pile cap. Pile caps generally are poured, reinforced concrete slabs, specifically engineered for that purpose. A larger number of anchor pile pairs is required when testing pile groups.
After the test, anchor piles are left in place, after sawing off their tops, i.e., after sawing-off the top portion of the pile protruding above ground. It is extremely difficult and expensive to pull those anchor piles out of the ground.
Utilizing anchor piles for testing an installed pile or a group of piles presents several drawbacks.
One drawback of the conventional pile testing apparatus and methods is the large installation cost of driving into the soil one, two, or more pairs of anchor piles per each single pile or group of piles to be tested.
Another drawback of the conventional pile testings is the difficulty in handling the long and heavy anchor piles required for the testings, e.g., requiring a tractor and a trailer for their transportation, requiring a special crane for lifting in or out of the trailer, requiring an expensive, cumbersome pile driving machine for driving the anchor piles into the ground.
Another drawback of the conventional pile testings is the difficulty of setting the long and heavy anchor piles in a vertical position for driving them into the ground.
Yet another drawback of the conventional pile testings is the loss of the anchor piles, because after the test is completed, they are not reusable in future tests, and therefore, their top ends protruding above the ground have to be sawed off, abandoning the pile in the ground.
It is an object of the present invention to provide anchoring apparatus and installation methods which substantially reduce the cost of testing piles or group of piles.
Another object of the present invention is to provide anchoring apparatus and methods which simplify the pile testing process.
Yet another object of the present invention is to provide anchoring apparatus and methods for the testing of piles which simplify transportation and eliminate utilizing a tractor and a trailer.
Still another object of the present invention is to provide anchoring apparatus and methods for the testing of piles which do not require the use of a pile driving machine.
Another object of the present invention is to provide anchoring apparatus and methods for the testing of piles which do not require the use of anchor piles for the pile testing process.
Yet another object of the present invention is to provide anchoring apparatus and methods for the testing of piles which are reusable.
These and other objects of the present invention will become apparent from a careful review of the detailed description and the figures of the drawings, which follow.
SUMMARY OF THE INVENTION
The apparatus and method of the present invention provide novel means and method for testing piles for load bearing capacity. The novel means and method of the present invention include applying a static compressive force on a pile or group of piles to be tested for load bearing capacity, receiving an equal and opposite reaction force on an I-beam, providing at least two reaction anchor assemblies on opposite sides of the pile, and bracing the I-beam by the two reaction anchor assemblies to hold the I-beam stationary in counter-action against the opposite reaction force on the I-beam. In one aspect, each reaction anchor assembly has an anchoring head, a pipe column, a center, a pulling rod passing through the center, a pair of swingable anchoring plates and preferably two pairs of swingable anchoring plates, and a frusto-cone for pivoting the swingable anchoring plates. In one aspect, the pipe column has four fins welded longitudinally along the pipe column. In one aspect, the reaction anchor assembly is preassembled for transportation to a pile test site. The novel means and method for testing piles provide for retrieving the reaction anchor assemblies from the ground after completion of the pile test and reusing the reaction anchor assemblies from one pile test site to another.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an elevation view showing the single pile testing apparatus of the existing art.
FIG. 2 is an elevation view showing the pile group testing apparatus of the existing art.
FIG. 3 is an elevation view, partially in section, showing a single pile testing apparatus of the present invention. FIG. 3 also shows some measuring instruments.
FIG. 4 is a perspective view of FIG. 3 without showing instrumentation.
FIG. 5 is an elevation view, partially in section, of a reaction anchor and support assembly in accordance with the apparatus and methods of the present invention. FIG. 5 shows a hydraulic assembly utilized for anchoring the reaction anchor and support assembly, also in accordance with the apparatus and methods of the present invention.
FIG. 6 is a detail view of a hydraulic system component part of the present invention, shown in elevation.
FIG. 7 is a detail elevation view of a hydraulic system component part of the present invention, also showing a load cell and a read-out with a graph print out.
FIG. 8 is a detail perspective view of a rod-centering box component part of the present invention shown in elevation on FIG. 3 . FIG. 8 shows a centering and support plate lifted up from the box.
FIG. 9 is an elevation view, partially in section, showing a pile group testing apparatus of the present invention, utilizing a concrete pile cap. FIG. 9 also shows some measuring instruments.
DETAILED DESCRIPTION
FIG. 1 and FIG. 2 depict apparatus and method representing the conventional testing apparatus and method for testing vertical piles, as shown on ASTM D1143-81 (reapproved 1987). FIG. 1 depicts the conventional testing apparatus and method for testing a single pile. FIG. 2 depicts the conventional testing apparatus and method for testing a group of piles.
Referring now to FIG. 1, a single pile 1 is shown as having been driven into soil 17 . A pair of anchor piles 7 also have been driven into soil 17 , at a distance at least seven feet away from or clear of pile 1 , i.e., away from the pile 1 under test. A bottom flange 19 of a test beam 6 is set on top of a bearing plate 5 of a piston ram 4 of a hydraulic cylinder 2 . The hydraulic cylinder 2 is set on a test plate 3 , which is centered on top of the individual pile 1 , i.e., the single pile 1 .
The test beam 6 is tied to the anchor piles 7 by means of a series of connecting rods 8 , a pair of plates 9 on a top flange 18 of the beam 6 , and the connecting rods 8 are secured by a series of threaded nuts 10 , threaded down against the plates 9 .
By the conventional method, a powerful, upwardly driven push is provided by the piston ram 4 of the hydraulic cylinder 2 , as represented by an arrow 15 . This upwardly driven push is exerted upon the test beam 6 , by means of a bearing plate 5 , which bears on the bottom flange 19 of the beam 6 . The beam 6 is fixedly connected to the anchor piles 7 by means of the threaded nuts 10 , tightened on the connecting rods 8 , against the plates 9 . As a result, the beam 6 cannot move up. The forceful push of the pistons 4 is effectively resisted by the anchor piles 7 because of the friction between the anchor piles 7 and the soil 17 . An equivalent forceful push therefore is exerted downwardly on the test plate 3 and, as a result, on the individual pile 1 .
Accordingly to ASTM D1143-81 (reapproved 1987), the load applied upon the pile 1 , which is the pile under test, must be 200% of the anticipated individual pile 1 design load.
The scope of purpose for testing piles is to determine if the pile has adequate bearing capacity, by measuring the response of the pile, e.g., the pile 1 , to a static, compressive load, axially applied, as shown by an arrow 16 of FIG. 1 .
In addition, pile testings also are utilized for measuring pile movements under axial loading. FIG. 1 shows a pair of dial gages 11 , connected by means of a pair of stems 20 to the pile 1 , at a pair of lugs 14 and to a pair of reference beams 13 by means of a pair of supports 12 .
Referring now to FIG. 2, the conventional testing apparatus and method for a group of piles 40 is represented. Pile group 40 includes, by the way of an example, the two piles 40 which have been driven into a soil 53 . A series of anchor piles 47 also have been driven into the soil 53 at a distance at least seven feet away from or clear of any pile 40 , i.e., the pile 40 of the pile group under test. A bottom flange 57 of a test beam 56 is set on top of a bearing plate 45 of a ram 44 of a hydraulic cylinder 43 . The hydraulic cylinder 43 is set on a test plate 42 , which in turn is set on a pile cap 41 . The pile cap 41 is centered on top of pile group 40 . The pile cap 41 is constructed of reinforced concrete, which is engineered to bear the anticipated load.
The test beam 56 has a pair of beams 61 on its top flange 46 . A pair of beams 58 are set with their bottom flanges 59 on top of the I-beams 61 . This I-beam set up is all tied down to the anchor piles 47 by means of a series of connecting rods 48 and threaded nuts 52 , with a plate 51 on top of each flange 60 . The threaded nuts 52 are tightened down against the plates 51 .
By the conventional method, a powerful, upwardly driven push is provided by the piston 44 of the hydraulic cylinder 43 , as represented by an arrow 54 . This upwardly driven push is exerted upon the test beam 56 by means of the bearing plate 45 , which bears on the bottom flange 57 of the beam 56 . The beam 56 is fixedly connected to the anchor piles 47 by means of the threaded nuts 52 tightened on the connecting rods 48 , against the plates 51 . As a result, the beam 56 cannot move up. The forceful push of the piston 44 is effectively resisted by the anchor piles 47 because of the friction between the piles 47 and the soil 53 . An equivalent, forceful push is exerted therefore downwardly upon the test plate 42 , the pile cap 41 , and the pile group 40 , as represented by an arrow 55 .
Accordingly to ASTM D1143-81 (reapproved 1987), the load applied upon the pile group 40 , which is the pile group under test, must be 150% of the anticipated pile group 40 design load.
These ASTM tests are performed to determine if the pile group has adequate bearing capacity by measuring the response of the pile group, e.g., the pile group 40 , to a static, compressive load applied axially, as shown in FIG. 2 .
The pile group 40 also is tested to determine movements which occur under loading. FIG. 2 shows a pair of dial gages 51 connected by means of a pair of stems 49 to a pile cap 41 and to a pair of reference beams 53 by means of a pair of supports 52 .
Referring now to FIG. 3, a pair of reaction anchor and support assemblies 125 in accordance with the apparatus and the methods of the present invention are shown in the process of testing a single pile 90 under a static, axial load, provided by a hydraulic assembly 145 . The reaction anchor and support assemblies 125 provide a point of resistance for a pair of hydraulic cylinders 93 to push against, as the hydraulic cylinders 93 exert a specified testing load on the pile 90 , as further described in this detailed description. The reaction anchors and support assemblies 125 are manufactured by SAFE Foundations, Inc., of Pittsburgh, Pa.
The hydraulic cylinders 93 are set on a bearing plate 91 , also known as a test plate 91 , with a pair of pistons 94 , respectively, upon which a bearing plate 92 is set. The hydraulic assembly could include only a one cylinder and one piston set instead of the pair of cylinders and pistons as shown in FIGS. 3 and 6. A load cell 121 is set between the bearing plate 92 and a bearing plate 122 . The bearing plates 91 , 92 , and 122 are of sufficient thickness to support the test loads provided by the hydraulic assembly 145 without bending, but not less than two inches thick.
The plate 122 bears against a flange 142 of a novel I-beam assembly 116 . The I-beam assembly 116 bears against an I-beam assembly 115 , which is identical to the beam assembly 116 . A pair of flanges 143 of the I-beam assembly 115 are set on top of a pair of flanges 105 of the I-beam assembly 116 . The beam assembly 115 is set at ninety degrees of the beam assembly 116 and on top of the beam assembly 116 , as shown in FIG. 4, a perspective view, showing some of the elements shown in FIG. 3 .
Referring now to FIGS. 3, 4 , and 8 , each of the beam assemblies 115 and 116 is constructed of two parallel I-beams, with one rod centering box 96 at each end of each assembly 115 and 116 . A detail of the rod centering box 96 is shown in FIG. 8, a perspective view of rod centering box 96 .
One box 96 is welded at each end of each beam assembly 115 and 116 . The boxes 96 are made of plates 99 welded to the top flanges 105 and 106 of the beam assembly 116 and 115 , respectively, and of L-shaped bars 100 , also welded to the flanges 105 and 106 , respectively. The rod centering boxes 96 are completed by plates 97 , also welded to flanges 105 and 106 respectively. The plates 99 are also welded to the angled bars 100 and to the plates 97 . Angled bars 104 are welded to each end of the I-beams 115 and 116 , respectively. With one rod centering box 96 , and one angled bar 104 welded to each end of each pair of I-beams, very strong, novel reaction frames, i.e., beam assemblies 115 and 116 , are formed. Support plates 101 , shown lifted-up from box 96 in FIG. 8 are utilized to receive threaded rods 102 of the reaction anchor and support assemblies 125 . Nuts 103 in FIGS. 3 and 4 are threaded onto the rods 102 and tightened against the support plates 101 . The plates 101 can slide inside their respective centering box 96 to facilitate positioning the beam assemblies 115 and 116 over rods 102 .
Referring now to FIGS. 3 and 7, the hydraulic assembly 145 is shown set upon the test plate 91 . The test plate 91 is set on top of the pile 90 , which is the pile under test, as shown in FIG. 3 .
To test the pile 90 for determining its capability of supporting its design load, a compressive load is axially applied upon the longitudinal axis of the pile 90 , the compressive load being provided by the hydraulic assembly 145 .
The pistons 94 of the hydraulic assembly 145 forcefully push, upwardly, against the bearing plate 92 . This upward push of the pistons 94 is transmitted to the beam assemblies 115 and 116 . Since the beam assemblies 115 and 116 are anchored by the reaction anchor and support assemblies 125 , the beam assemblies 115 and 116 cannot move upwardly. The forceful upward push of the pistons 94 , as they are forced out of their respective cylinders 93 , is actually exerted axially, downwardly upon the pile 90 , by means of the bottoms of the cylinders 93 , upon the bearing plate 91 .
Referring to FIG. 3, a pair of dial gages 109 have their stems 118 connected to a top surface 191 of the bearing plate 91 and to a pair of reference beams 110 by means of a pair of supports 147 . The stems 118 must have, at a minimum, two inches (5 cm) of travel, must have a precision of at least 0.01 inches (0.25 millimeters) and must read to one sixty-fourth (1/64) of an inch (4 mm).
The dial gages 109 provide the measurement of any longitudinal axial movement of the pile 90 under the axial loading provided by the hydraulic assembly 145 . Any axial movement beyond that specified renders the pile 90 unacceptable for its specified load.
Referring to FIGS. 3 and 6, the hydraulic assembly utilized in the apparatus and the method of the present invention could include a single hydraulic cylinder with its piston or a pair of cylinders 93 of a hydraulic assembly 95 of FIG. 6, with a pair of pressure gages 117 , one pressure gage 117 for each hydraulic cylinder 93 and a master pressure gage 116 , and further includes a hydraulic pump 113 and an automatic pressure control device 114 . The cylinders 93 are connected to the pump 113 by a pair of common manifolds 111 and hoses 112 . The complete hydraulic assembly 95 is to be calibrated as a unit, including the hydraulic cylinders 93 , the pistons 94 , the pressure gages 117 and 116 , the pump 113 , and the automatic pressure control device 114 .
FIG. 7 represents the preferred embodiment of the hydraulic means utilized by the apparatus and the methods of the present invention. The hydraulic assembly 145 is very similar to the hydraulic assembly 95 . Nevertheless, the hydraulic assembly 145 utilizes a calibrated load cell 121 between the bearing plate 92 and the bearing plate 122 . In accord with the apparatus and the methods of the present invention, the calibrated load cell 121 is connected to a read-out and load graph recorder 124 . The read-out recorder 124 provides a graph 148 showing the load applied during a 24-hour period. The calibrated load cell 121 and the read-out and load graph recorder 124 substantially improve the accuracy and reliability of the measurements of the loads applied to the pile-under-test 90 . The preferred embodiment for the hydraulic means, e.g., the hydraulic assembly 145 , also includes the pressure gages 117 , one for each hydraulic cylinder 93 and the master pressure gage 116 , the hydraulic pump 113 , and the automatic pressure control 114 . The cylinders 93 are connected to the pump 113 by the common manifolds 111 and the hoses 112 . This apparatus and method provide a dual measuring system. The load cell 121 must be calibrated to an accuracy of not less than 2% of the applied load.
Referring again to FIG. 3, the reaction anchor and support assemblies 125 , also referred to as anchor assemblies 125 , are shown inside earthen holes 126 . The reaction anchor and support assemblies 125 include anchoring heads 133 and a pipe column 128 , which has four fins 129 , only three shown, welded longitudinally to the surface of pipe column 128 and at ninety degrees to each other. The pipe columns 128 also have top plates 130 welded to their tops, which have a center hole to allow Dywidag Rod 102 pass through it, with a minimum clearance, in order to allow Dywidag nuts 132 to be tightened against the plates 130 when threaded down on the Dywidag rods 102 . The Dywidag rods, the nuts, and other Dywidag products are manufactured by Dywidag-Systems International, U.S.A., Inc., of Fairfield, N.J.
The anchoring heads 133 have the Dywidag rods 125 and a plate support 138 formed by four ninety-degree bars, only two being shown, with a plate 137 welded on their top and four compaction and consolidation pivoting plates 139 , only three being shown. A collar 135 is welded on top of the plate 137 and is utilized to insert end 134 of the pipe column 128 into the collar 135 or over the collar 135 , depending on pipe sizes utilized. Four bolts 136 , only three shown, are utilized for firmly securing the pipe column 128 to the anchor head 133 . The Dywidag rod 102 is inserted through a centerhole in a frusto-cone 140 . A Dywidag nut 141 is threaded on the end of the rod 102 and prevents the frusto-cone 140 from falling down.
A nut 168 is hand tightened on the Dywidag rod 102 , on top of the frusto-cone 140 , as seen in FIG. 4 . The main purpose of the nut 141 is to carry the frusto-cone 140 upwardly whenever the rod 102 is pulled up, during the process of anchoring the reaction anchor and support assembly 125 , prior to installing the test beam assemblies 115 and 116 .
During the installation of the reaction anchor and support assemblies 125 , hydraulic force is utilized for pulling up on the rod 102 . The pulling on the rod 102 forces the nut 141 to push the frusto-cone 140 upwardly, which in turn pushes the compaction and consolidation pivoting plates 139 upwardly and outwardly. The pulling on the rod 102 makes the pivoting plates 139 swing upwardly and outwardly, thereby compacting and consolidating soil 127 at the bottom of the earthen hole 126 , effectively anchoring the assembly 125 against the soil 127 at the bottom of the earthen hole 126 , thus providing the reaction point needed for the pile test. A nut 132 is threaded downwardly and hand tightened against the plate 130 at the top of the pipe column 128 in order to prevent the rod 102 and the frusto-cone 140 from moving back down.
The top end of the reaction anchor and support assembly 125 is left a few inches above grade in order to facilitate its retrieval for further use. Holes 131 are utilized for hooking a lifting device.
The reaction anchor and support assemblies 125 are installed at a distance of at least seven feet, clear distance, from the pile 90 .
The pile 90 of FIG. 3 is shown as a round, cylindrical pile. Nevertheless, the pile 90 can be an H-pile, an L-pile, a square pile, or an orthogonal pile. The pile 90 can be a concrete pile, whether cast-in-place or pre-cast, a pipe pile, or a timber pile, by the way of an example.
The test set up shown in FIG. 3 requires four reaction anchor and support assemblies 125 , as shown in FIG. 4, in order to provide an anchored reaction capacity, which is greater than the axial load applied to the pile 90 by the hydraulic assembly 145 . The axial loading or test loading required for testing single piles is at least 200% of the pile design load capacity. Nevertheless, smaller piles require smaller test loads, and only one pair of reaction anchor and support assemblies 125 are required for smaller piles.
On occasion, three pairs of reaction anchor and support assemblies 125 are required. In such cases, an additional beam assembly is installed upon the beam assembly 115 and at forty-five degrees from it. The additional pair of reaction anchor and support assemblies are installed as shown for the beam assemblies 115 and 116 and in a substantially similar manner as shown for the reaction anchor and support assemblies 125 of FIGS. 3 and 4.
Referring now to FIG. 5, one reaction anchoring and support assembly is shown of the four reaction anchoring and support assemblies of FIGS. 3, 4 , and 9 . The one reaction anchoring and support assembly is shown in the process of being installed inside a pre-augured earthen hole 126 , in preparation for utilization in the testing of the single pile 90 of FIG. 3 or group pile 180 of FIG. 9 .
The reaction anchor and support assembly 125 of FIG. 5 provides the anchored reaction capacity required to resist the upward push of the hydraulic assemblies 145 of FIGS. 3, 4 , and 9 . The upward push of the hydraulic assemblies 145 provides the resultant downward axial loading required for testing the single pile 90 of FIG. 3 or the group pile 180 of FIG. 9 .
The reaction anchor and support assemblies 125 are brought to the test site in one piece, pre-assembled, with the anchoring head 133 pre-attached to the rod 102 and with the rod 102 inside the pipe column 128 . The compaction and consolidation pivoting plates 139 come to the test site vertically down and parallel to the rod 102 , with the frusto-cone 140 below the tip end of the compaction and consolidation pivoting plates 139 . The frusto-cone 140 is sandwiched between the nut 168 , on its topside, as shown in FIG. 4 and the nut 141 on its bottom side as shown in FIG. 5 . The pivoting plates 139 come with breakable tie-wire (not shown) around them, in order to keep them in a vertical position, which facilitates lowering down the anchor assembly 125 inside the pre-augured earthen hole 126 . The nut 132 comes to the test site hand tightened against the plate 130 .
The reaction anchor and support assembly 125 is lowered down inside the earthen hole 126 . About six inches of the top end of the reaction anchor and support assembly 125 is left above ground level 166 . A centering collar 163 is placed over the assembly 125 and pushed down inside the earthen hole 126 , until its plate 162 rests on surface 166 of the soil 126 . The collar 163 is about twelve to eighteen inches long. The centering collar 163 is utilized for centering the reaction anchor assembly 125 inside the earthen hole 126 and to make sure it is fixed in a true, vertical and leveled position. When the correct leveling is attained, four pins 165 (only two are shown) are hammered down into the soil 127 , through holes 164 of the plate 162 , in order to immobilize the centering collar in a vertical position.
Next, the hydraulic assembly 150 is placed over the rod 102 , i.e., with the rod 102 passing through openings 155 and 156 on plates 152 and 153 , respectively. This is done by means of a crane, which is available at the job site anyways for handling the piles. The hydraulic assembly 145 of FIG. 7 could be utilized instead of the hydraulic assembly 150 of FIG. 5, if plates 91 , 92 , 94 , and the load cell 121 had an opening through their center, for allowing the rod 102 pass through it.
The preferred embodiment provides for utilizing one single hydraulic assembly to perform both the installation of all the reaction anchor and support assemblies 125 prior to testing, as well as providing the specified loading for testing the single pile 90 of FIG. 3 or the pile group 180 of FIG. 9 . In such an embodiment, the load cell 121 also has a center hole. If the load cell 121 also is utilized for installing the anchor assembly 125 , then it could be installed between the plate 91 of FIG. 7 and the plate 130 of FIG. 5 . The utilization of the load cell 121 and the read-out/graph recorder 124 is not a requirement for the installation of the reaction anchoring and support assemblies 125 . Nevertheless, the utilization of the load cell 121 and the read-out/graph recorder 124 is an additional quality control feature as well as a record keeping feature and a component part of the present invention.
When the hydraulic assembly 150 is set on top of the plate 130 , a plate 167 is placed over the rod 102 and set on top of the plate 153 to reduce the actual size of opening 156 so that the Dywidag nut 103 can be threaded down on the rod 102 and hand tightened against the plates 167 and 153 .
The hydraulic assembly 150 has cylinders 151 connected by means of hoses 158 through the assembly's inlets 157 to a hydraulic pump 159 . A master pressure gage 168 is provided in series with both the cylinders 151 and the pump 159 . A pressure gage 169 provides a reading of the pressures applied by the pistons 154 , in pounds per-square inch, p.s.i. The total force exerted by the assembly is directly proportional to the diameter of pistons 154 . The diameter of the pistons 154 determines the area in square inches of the cross section of each piston 154 , which pistons 154 are substantially identical pistons. Therefore, the total combined area is determined in advance.
The operator is provided with a simple table showing how many tons-force are equivalent to various p.s.i. readings from the gage 169 . The operator does not calculate anything. The compaction and consolidation pivoting plates 139 are at the bottom of the earthen hole 126 in a vertical position parallel to the rod 102 . The next step is to swing upwardly the pivoting plates 139 to anchor the assembly firmly against the soil 127 at the bottom of the hole 126 .
The operator provides hydraulic pressure to the cylinder 151 , through the bottom inlets 157 , which forces the pistons 154 upwardly. The pistons 154 forcefully push against the plates 153 , 167 and the nut 103 . That forceful upward push as represented by arrows 160 and as exerted on the nut 103 , which is threaded onto the rod 102 , lifts the rod 102 up, which in turn carries the nut 141 up with it. The nut 141 is threaded to the bottom end of the rod 102 . The nut 141 pushes up the frusto-cone 140 , which in turn forces the pivoting plates 139 to break their tie-wire (not shown). The pivoting plates 139 are forced to swing upwardly, compacting and consolidating the soil 127 at the bottom of the hole 126 by the expanding plates, i.e., by the expansion of the pivoting plates 139 , thereby powerfully anchoring assembly the 125 to the soil at the bottom of the hole 126 . As the rod 102 is being slowly, yet powerfully pushed upwardly, the operator hand-tightens down the nut 132 against the plate 130 , thereby preventing the pivoting plates 139 from collapsing back down, which is a very rear situation.
Now the hydraulic assembly 150 is removed, by first reversing the flow of hydraulic fluid, which now is pumped by the pump 159 , through the upper inlets 157 , which in turn brings the pistons 154 back inside of their respective cylinders 151 . Then the hydraulic pressure is released and the nut 103 and the plate 167 are removed. Finally, the hydraulic assembly 150 is removed and the installation of the next anchoring assemblies 125 can be started, until all four assemblies required per FIG. 3, 4 and 9 are installed.
Preferably, the centering collar 163 stays installed, one on each anchoring assembly 125 until the pile test is concluded and the anchoring assemblies 125 are removed.
As opposed to the conventional methods, whereby the anchor piles utilized in the testing remain in the ground and their tops must be sawed off, the reaction anchoring and support assemblies 125 are reusable.
The anchoring and support assemblies 125 are retrievable. They are retrieved from the earthen hole 126 utilizing the same hydraulic assembly they were installed with.
In order to retrieve the reaction anchor and support assemblies 125 from the earthen hole 126 , after the pile testing is completed, first the operator places the hydraulic assembly 150 once more over the rod 102 , by means of an on-site crane. Then the operator lowers the assembly down so that the rod 102 passes through the hole 155 on the bottom plate 152 and through the hole 156 of the top plate 153 . Now, the plate 167 is reinstalled, and the nut 103 is rethreaded down on the rod 102 and hand tightened against the plate 167 .
The operator then pumps hydraulic fluid through the lower inlets 157 , by means of the pump 159 . This forces the pistons 154 out of their respective cylinders 151 , slowly but forcefully pushing upwardly against the plates 153 and 167 and on the nut 103 which, being threaded onto the rod 102 , slowly lifts the rod 102 upwardly. This is done just enough to release the enormous pressure exerted by the nut 132 against the plate 130 at the time the anchor and support assembly 125 was installed. Now the operator threads the nut 132 upwardly on the rod 102 and then releases the pressure from the pump 159 , which releases the upward push of the pistons 154 .
Next the nut 103 and the plate 167 are removed, and the operator pumps again hydraulic fluid through the lower inlets 157 , by means of the pump 159 , to make the pistons 154 extend out of the cylinders 151 for a distance which is approximately equal to the distance the pistons 154 were extended during the process of installation. The hydraulic assembly then is lifted up again, by means of a crane, just enough, so that the top end of the rod 102 is below the plate 153 , in order to allow re-introducing the plate 167 , which now will be on top of the nut 132 , which has been threaded up.
Then, the operator lowers down the hydraulic assembly and sets its bottom plate 152 back on top of the plate 130 of the reaction anchor and support assembly 125 and with the rod 102 passing through the hole 156 of the top plate 153 .
The operator further threads up the nut 132 carrying the plate 167 upwardly until the plate 167 is against the bottom of the plate 153 with the nut 132 hand-tightened under it.
Now the operator pumps hydraulic fluid through the upper inlets 157 , which forces the pistons 153 back down, slowly but forcefully pushing downwardly on the nut 132 , which now is under the plates 167 , 153 and is threaded onto the rod 102 . Therefore the pistons 154 , slowly yet powerfully, push the rod 102 down. Since the nut 168 , shown on FIG. 4, is threaded onto the rod 102 and it is on top and in contact with the frusto-cone 140 , it pushes the frusto-cone 140 also downwardly. By pushing the frusto-cone 140 downwardly, the compaction and consolidation pivoting plates 139 are effectively released from the powerful force which kept them pressed against the soil at the bottom of the earthen hole 126 .
With the pivoting plates 139 collapsed back down to a vertical position, now the hydraulic assembly can be finally removed, as previously described, after releasing the hydraulic pressure.
A job-site crane then is utilized for lifting the anchor and support assembly 125 out of the earthen hole 126 . Openings 131 on fins 129 are utilized for helping in lifting the assembly by means of devises and the job-site crane.
Referring now to FIG. 9, the reaction anchor and support assemblies 125 , utilized by the methods of the present invention, are shown in the process of testing a pile group 180 under a static axial load provided by the hydraulic assembly 145 .
The pile group 180 includes two or more single piles 182 . The pile group 180 is capped with a reinforced concrete cap 181 engineered and constructed specifically for the anticipated test loads.
The hydraulic cylinders 93 are set on the bearing plate 91 , with their respective pistons 94 , upon which the bearing plate 92 is set. The load cell 121 is set in between the bearing plate 92 and the bearing plate 122 . The bearing plates 91 , 92 and 122 are of sufficient thickness to support the test loads provided by the hydraulic assembly 145 without bending, but not less than two inches thick.
The plate 122 bears against the flange 142 of I-beam assembly 116 . The I-beam assembly 116 bears against the I-beam assembly 115 , which is identical to the beam assembly 116 . The flanges 143 of the I-beam assembly 115 are set on top of the flanges 105 of I-beam assembly 116 . The beam assembly 115 is set at ninety degrees of the beam assembly 116 in the horizontal plane and on top of it.
The construction of the I-beam assemblies 115 and 116 of FIG. 9 is substantially the same as described in reference to FIGS. 3 and 4. The hydraulic assembly 145 of FIG. 9 also is substantially the same as described in reference to FIGS. 3 and 7. Nevertheless, for the pile group 180 testings, a larger axial load is required, for a larger capacity for the hydraulic cylinders 93 , with their respective pistons 94 , possibly, of larger diameter than it would be required for single pile testings.
The reaction anchor and support assemblies 125 of FIG. 9 are also substantially the same as described in reference to FIGS. 3, 4 and 5 . On occasion, a third pair of assemblies 125 is utilized in order to provide the reaction capacity required for the loading specified for a specific pile group test.
Continuing to refer to FIG. 9, the instrumentation set up is substantially similar to that described in reference to FIG. 3 . Nevertheless, for the group pile testing of FIG. 9, the dial gages 109 have their stems 118 connected to the top of the concrete cap. The dial gages 109 are connected to reference the beams 110 by means of the supports 147 . The stems 118 must have, at a minimum, two inches (5 Cm) of travel, must have a precision of at least 0.01 inches (0.25 millimeters) and must read to one sixty-fourth (1/64) of an inch. These dial gages provide the measurement of any longitudinal axial movement of the pile group 180 under the axial load provided by the hydraulic assembly 145 . Any axial movement beyond that specified, renders pile 90 unacceptable for its specified load.
Other instrumentation means are available for measuring other single pile and group pile movements under axial test loadings.
By the novel methods of the present invention, single piles or group piles are tested utilizing one, two, or more pairs of reaction anchor and support assemblies, as shown in FIGS. 3, 4 , and 9 and as described in the detailed description, instead of utilizing one, two, or more pairs of anchor piles which cannot be reutilized for future pile or pile group tests.
The testing process of the present invention does not depart from the procedures established by the A.S.T.M. standards for testing piles or pile groups. The novelty of this invention includes the utilization of the novel anchor and reaction anchoring and support assembly in combination with the novel I-beam assembly, with a built-in centering box. This combination, in addition to its reusability feature, is a safer and more reliable anchoring system than the conventional anchor piles utilized by the conventional methods. The mechanical connections between the conventional reaction beam and the conventional anchor piles of the conventional methods are substantially more susceptible to elongation under the axial pressures involved in the test than the Dywidag rod and Dywidag nuts combination utilized by this invention.
The component parts of the reaction anchor and support assembly of this invention have been utilized under axial loadings several times larger than the loads involved in pile tests.
The safety and reliability of the methods of this invention are demonstrated further by the anchoring method of this invention, which compacts and consolidates the soil it is anchored to, with the compaction and consolidation increasing, thus increasing the anchoring capacity, as the test loading increases. This can be understood readily by looking at the drawings in FIGS. 3, 5 , and 9 , showing the swingable pivoting plates anchored and pushing upwardly, at the bottom of an earthen hole, such that the more the test load pulls up on the Dywidag rod, the more powerfully the anchoring head gets anchored to the soil at the bottom of the hole.
The apparatus and method of the present invention substantially contrast with the conventional anchor piles, which depend absolutely on the friction between the pile and the soil into which it was hammered down. In the conventional application, the more the test load pulls the anchor pile up, the greater are the chances the pile will slide up, and often the piles do slide up.
As it can be seen by a review of the detailed description, the apparatus and method of the present invention accomplish all of its stated objectives. The apparatus and methods of the present invention are capable of modifications and variations without departing from the scope thereof. Accordingly, the detailed description and examples set forth above are meant to be illustrative only and are not intended to limit the scope of the invention as set forth in the appended claims. | A novel apparatus and method are disclosed for testing piles for load bearing capacity. The novel means and method of the present invention include applying a static compressive force on a pile or group of piles to be tested for load bearing capacity, receiving an equal and opposite reaction force on an I-beam, providing at least two reaction anchor assemblies on opposite sides of the pile, and bracing the I-beam by the two reaction anchor assemblies to hold the I-beam stationary in counter-action against the opposite reaction force on the I-beam. In one aspect, each reaction anchor assembly has an anchoring head, a pipe column, a center, a pulling rod passing through the center, a pair of the swingable anchoring plates, and a frusto-cone for pivoting the swingable anchoring plates. In one aspect, the pipe column has four fins welded longitudinally along the pipe column. In one aspect, the reaction anchor assembly is preassembled for transportation to a pile test site. The novel means and method retrieve the reaction anchor assemblies from the ground after completion of the pile test and reuse them from one pile test site to another. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
This is a continuation of Ser. No. 10/348,578 filed Jan. 20, 2003 now U.S. Pat. No. 7,114,494, which is a continuation-in-part of Ser. No. 09/661,957 filed Sep. 14, 2000, now U.S. Pat. No. 6,626,166, which is a division of Ser. No. 09/399,297 filed Sep. 17, 1999, now U.S. Pat. No. 6,318,351, all of which are incorporated herein by reference.
BACKGROUND OF THE INVENTIONS
1. Field of the Invention
The present inventions relate to abrading and cutting devices and methods, and more specifically to waste containment systems and methods for such devices and methods, for example slurry containment systems and methods for saws, cutters and the like.
2. Related Art
Pavement treatment apparatus and methods are known for concrete and asphalt saws which may include a vacuum apparatus for removing water and particulate matter, commonly referred to as slurry, from a work site. See Bassols, U.S. Pat. No. 5,564,408, entitled Pavement Treatment Method and Apparatus, the specification and drawings of which are incorporated herein by reference. As discussed in that patent, concrete and asphalt saws are typically used to cut joints for expansion and contraction of such materials in freeway pavement, aircraft runways, and other pavement surfaces. Typical saws are marketed under different brand names and include a diamond blade of different diameters according to the thickness of the pavement to be cut, such as 12, 14, 16, or 24-inch blades, etc., driven by an internal combustion engine. The engine is also used to drive a traction mechanism at the rear of the saw for advancing the saw along the pavement. A belt takes power from a pulley driven by the internal combustion engine for powering a transmission box to step down the revolutions per minute (rpm) of the engine to a suitable rate for driving the traction wheels of the saw and for driving the saw blade.
The saw blade includes a blade guard for protecting the blade during operation and for preventing injury while the blade is rotating. The blade guard also contains cooling water sprayed onto the blade so that the cooling water drops onto the pavement.
The saw also includes a structural support frame for supporting all of the components and for mounting the wheels to the saw. The frame supports the engine, the shaft for driving the saw blade, the traction transmission and the pulleys for powering the traction transmission from the engine, among other elements.
In operation, the saw is started and positioned in alignment with the desired cutting path, and lowered into engagement with the pavement while at the same time turning on the coolant spray to the blade. An additional vehicle or other source is located nearby for supplying water for cooling the blade through a suitable hose. As cutting continues, the water and resulting slurry from the abraded pavement is picked up by a suction or vacuum bar to minimize filling previously cut joints. The slurry and any air picked up by the vacuum bar is taken back to a separator tank for removing the slurry. A disposal hose transports waste from the collection tank through a diaphragm pump to a truck or other container for disposal.
SUMMARY OF THE INVENTIONS
Waste containment systems and methods are described for abrading and cutting apparatus which provide improved removal of slurry and improved operating life of various components in the system. Such systems and methods may be used on saws, such as pavement and concrete saws, other cutting tools, such as wall saws, core drills and other boring equipment, and the like. The systems and methods may be implemented as original equipment or as accessories in kit form or individual components.
In one aspect of one of the inventions, a material pickup element is provided for picking up a fluid, which may include solid particles forming a slurry. The pickup element may be a vacuum bar, vacuum shoe or other suction device, for example. Element includes a number of openings comprising at least one and preferably a set of low vacuum apertures and at least one and preferably a second set of high vacuum apertures. In a preferred embodiment, the high vacuum apertures pickup most if not all of the slurry, and the low vacuum apertures focus, collect, concentrate or align the slurry so that it can be more easily picked up by the high vacuum apertures. For example, the low vacuum apertures can center or bring in fluid from both sides of the vacuum element so that an adjacent high vacuum aperture can pickup the slurry. Using both low and high vacuum apertures helps to conserve vacuum pressure, or minimize the loss of vacuum through larger openings, especially where the amount of vacuum available is limited or fixed. Conversely, using both low and high vacuum apertures permits placement of high vacuum areas where they may be most beneficial, and reduction of aperture size at other areas of the pickup element where high vacuum would not have significant incremental value over others already included.
In one preferred form of the pickup element, the low vacuum apertures are round or similar holes and the high vacuum apertures are extended slots in the pickup element. The round holes may be grouped in a series, and the round holes may be co-linear with a slot. Other configurations, arrangements and orientations for the openings can be used.
In one preferred aspect of one of the inventions, the pickup element is used on a concrete or similar saw which moves along the work surface. The openings are preferably distributed over the pickup element so as to take advantage of the forward or backward motion of the saw. In one preferred embodiment, the high vacuum apertures are placed in front of the low vacuum apertures, which in turn may be followed by one or more additional high vacuum apertures. Alternatively, high and low vacuum apertures may alternate along the pickup element, for example beginning and ending with high vacuum apertures. The pickup element can then bring in fluid from both sides of the element, minimize or limit flow over the work surface and tailor the location or flow of the slurry relative to the pickup element.
In a further preferred aspect of one of the inventions, one or more of the apertures or openings may extend along a surface of the pickup element in a direction at least partly perpendicular to the work surface. For example, in a vacuum bar that extends horizontally, most of the apertures can open downwardly and extend horizontally over a horizontal surface of the vacuum bar and a high vacuum aperture can extend vertically or in a direction other than downwardly. A vertically extending high vacuum aperture can be advantageous directly behind the saw blade.
In a further aspect of one of the inventions, a system can be used for designing pickup elements. The system can include a processor or computer loaded with a computational fluid dynamics fluid flow optimizing program to optimize the flow of the slurry and maximize the suction created by the fan. Input parameters include maximum vacuum available, desired fluid flow rates through the pickup element, and the like. The system preferably identifies possible as well as optimum sizes and configurations for pickup elements, and potential and optimum sizes, configurations and distributions of vacuum openings. In one preferred embodiment, the system is used to identify the sizes, shapes and locations of openings to be used for picking up slurry, in addition to the sizes, shapes and locations of openings to be used for focusing, channeling or otherwise controlling flow of the slurry away from the pickup element.
In a further aspect of one of the inventions, the pickup element can include removable end caps having curved surfaces for more easily negotiating or riding over pebbles or other objects which may be in the line of travel. Having removable end caps makes for easier cleaning of the pickup element.
In another aspect of one of the inventions, a tool guard such as a blade guard includes a water supply conduit or tube for projecting or spraying fluid onto the tool. The fluid may be used as a lubricant and/or coolant for the tool. The fluid is directed toward the tool at an angle different than 90 degrees. For example, the fluid can be directed backward toward an on-coming surface of the tool. Directing the fluid backward relative to the motion of the tool reduces the amount of fluid thrown forward of the tool. Consequently, the amount of fluid to be picked up at the front of the tool is reduced. In one preferred embodiment, the fluid is directed backward about three degrees from a line perpendicular to the tool, such as a blade.
In a further aspect of one of the inventions, a separation system and method are provided for separating air and a second fluid. A receptacle is provided for receiving a combination of air and the second fluid, the receptacle including at least two vertically extending walls joining at a vertically extending angle. An inlet receives a combination of air and the second fluid and allows the combination to flow into the receptacle. A first outlet passes the second fluid from the receptacle and a second outlet passes air from the receptacle. This configuration contributes to providing a receptacle which more completely separates the air from the second fluid. This configuration makes the flow and disposition of the second material more controlled or organized, while promoting more uncontrolled or disorganized air flow. This type of receptacle configuration also reduces any tendency toward cyclone-type action in the fluid flow, for the air and for the second fluid. It also reduces the amount of symmetry in the surfaces in the receptacle, and in combination with other features, reduces residual splashing of the second fluid.
In another aspect of one of the present inventions, an inlet for a separation system discharges the air and fluid combination closer to the bottom of the receptacle than to the top. With this configuration, the fluid has a shorter distance to travel to the bottom of the receptacle, reducing the amount of splashing and reducing the amount of time the moving air from the inlet is around the moving fluid from the inlet. Additionally, when the outlet for the air is at the top of the receptacle, the air will have more time and area for shedding fluid before leaving the receptacle. Consequently, the air leaving the receptacle has a lower fluid content. Furthermore, where the fluid has abrasive, corrosive or other harmful material, the amount of harmful material leaving the receptacle through the air outlet and reaching other components is reduced.
In an additional aspect of one of the present inventions, an air outlet for a receptacle in a separation system is positioned off of a line, axis or plane of symmetry. Positioning of the air outlet in this way removes air that is less controlled or less organized earlier than air in other locations of the receptacle where the air may be more channeled. In one preferred embodiment, the only plane or line of symmetry for the air outlet is one between vertically extending walls of the receptacle. Locating the air outlet on this plane of symmetry reduces the possibility of exiting air pulling with it condensed fluid from either of the walls.
In a further aspect of one of the present inventions, an inlet for a separation system discharges an air and fluid combination into a receptacle between two vertically extending walls, and closer to one vertically extending wall than to the other. This asymmetry tends to reduce splashing of the second fluid and contributes to greater control, containment or organization of the second fluid.
In one aspect of the present inventions, a tool is provided for working a material, such as cutting concrete, where the tool is driven by a drive element, such as a drive shaft. Vacuum is created by a vacuum generator driven by the same drive shaft that drives the tool. Such a design provides for a compact and self-contained combination of tool and waste containment system. The design also makes it easier to assemble the combination as a tool and kit for easy assembly and disassembly.
In another example of a tool guard, the tool guard has at least one wall with an edge portion extending adjacent a work piece to be operated on by the tool, and the at least one wall extends away from the edge portion, for example in the general direction in which the tool extends away from the work piece. A second wall portion contacts the at least one wall on the surface of the at least one wall which is on the same side as the tool is located, and extends from the wall in a direction away from the at least one wall, for example toward the tool. The second wall portion may start adjacent the edge portion and extend away from the edge portion, for example at an angle to that part of the edge portion where the second wall portion starts. In another example, the second wall portion may start further away from the edge portion and extend still further from the edge portion. In one example, the second wall portion is configured so the material can travel along the second wall portion in part through gravity and at least partly toward the edge portion.
In a further example of a tool guard, the tool guard has at least one relatively flat wall with a relatively straight edge portion extending adjacent a work piece to be operated on by the tool. The at least one wall extends away from the area of the work piece and extends generally adjacent the tool. A second wall portion fixed to the at least one wall includes a flange portion, which extends away from the at least one wall in the direction in which the tool is spaced from the at least one wall. Generally, the second wall portion extends along the at least one wall in a direction other than horizontal during normal operation of the tool. The second wall portion may have more than one segment, wherein one segment extends at an angle relative to the other segment. In one example, the tool is a saw blade and the tool guard is a blade guard wherein the second wall portion is on the same side of the at least one wall as the saw blade and extends away from the at least one wall. With many saw designs, the blade guard floats relative to the saw blade as the saw blade cuts into the work piece, with an edge portion of the at least one wall adjacent the work piece. The second wall portion generally includes a slope that allows material to flow along the second wall portion under the influence of gravity toward the edge portion. If the second wall portion has more than one segment, the segments can be oriented at angles relative to each other.
Another example of a tool guard has first and second oppositely facing walls extending on respective sides of a tool, for example a saw blade, and the first oppositely facing wall includes a third wall extending toward the second oppositely facing wall and the second oppositely facing wall includes a fourth wall extending toward the first wall. The first and second walls include respective edge portions adjacent a work surface and each of the third and fourth walls are preferably non-parallel with the edge portions. In one example, the third and fourth walls are positioned opposite each other. In a further example, the third and fourth walls each have first and second segments wherein the first segments are spaced apart from each other and wherein the second segments are joined by a joining wall. In another example, at least one of the third and fourth walls is configured to direct material flow to an outlet, opening or flow conduit, with the help of gravity or other forces. For example, where a fluid such as a liquid is used as the lubricant or coolant for the tool, the third and fourth walls may help flow material toward an outlet or disposal opening. The third and fourth walls, and any joining walls, can serve as water channels or water flow guides. The walls can also serve as baffles, vanes or other flow directors or flow preventers to help transmit fluid to a desired location or to limit flow in a given direction. For example, where the guard is used in conjunction with a vacuum assembly, the walls can be used to direct fluid toward a vacuum port. The walls may also limit the flow of fluid toward a back wall of the blade guard, for example.
In another example of a blade guard assembly, the assembly includes a blade guard support on a support surface, and a blade guard is configured to engage the support and be removable from the support. A blade guard support element on the blade guard support can be used to help support the blade guard. A rolling element on the blade guard support, such as a wheel, may be used to make easier the movement of the assembly, and permit the blade guard support to remain on the support surface when the blade guard has been removed.
In another example, a blade guard assembly includes a blade guard support and a blade guard, wherein the blade guard includes walls defining an opening for allowing fluid to flow from the blade guard to the support. In one example, the blade guard support includes a complementary opening for receiving the fluid, and where the blade guard support includes vacuum attachment means, vacuum can be used to remove fluid from the blade guard through the opening. One or more fasteners can be used to secure the blade guard to the blade guard support.
A tool guard and vacuum assembly has a tool guard extend adjacent the tool, and the vacuum assembly assembled with the tool guard has a plurality of walls defining openings. The vacuum assembly also includes two walls defining respective first and second passage ways communicating with two openings in the vacuum assembly. The first and second passage ways have different shapes. In one example, the passage ways have different cross-sectional areas. In another example, the passage ways follow different paths, and in a further example, the passage ways have different cross-sectional areas and follow different paths.
These and other aspects of the present inventions will be better understood after a consideration of the drawings, a brief description of which follows, and the detailed description of the preferred embodiments of the inventions.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a left front isometric view of a cutting device in the form of a saw incorporating a waste containment system in accordance with several aspects of the present inventions.
FIG. 2 is a top plan view of the saw of FIG. 1 .
FIG. 3 is a right side elevation view of the saw of FIG. 1 .
FIG. 4 is a left side elevation view of the saw of FIG. 1 .
FIG. 5 is a schematic and flow diagram showing the flow of air and fluids through a waste containment system in accordance with several aspects of the present inventions.
FIG. 6 is a lower left front isometric view of a blade guard support in accordance with another aspect of the present inventions.
FIG. 7 is a bottom plan view of the blade guard support of FIG. 6 .
FIG. 8 is a left front isometric view of a material pickup element such as a vacuum bar in the accordance with a further aspect of one of the present inventions.
FIG. 9 is a bottom plan view of the vacuum bar of FIG. 8 showing high vacuum and low vacuum openings.
FIG. 10 is a left side elevation view of a container and pump for use with the containment system of FIG. 1 .
FIG. 11 is a vertical cross-sectional view of the left side of the container and pump of FIG. 10 showing an air and slurry input, a waste output and an air output.
FIG. 12 is a horizontal cross-sectional view of the top of the container and pump of FIG. 10 showing the slurry input, the air output and a mounting assembly.
FIG. 13 is an upper right isometric view of the container and pump of FIG. 10 .
FIG. 14 is a partial left elevation view of the saw of FIG. 1 showing a vacuum generator and its drive mechanism.
FIG. 15 is a right side isometric view of the vacuum generator and its drive transmission assembly and mounting assembly.
FIG. 16 is a right side elevation view of the assemblies of FIG. 15 .
FIG. 17 is a side elevation view and partial cut-away of a blade guard showing water tubes for wetting the saw blade.
FIG. 17A is a detail of a water tube of FIG. 17 .
FIG. 18 is a bottom plan view of a vacuum bar having a further arrangement of openings.
FIG. 19 is a bottom plan view of a vacuum bar having another arrangement of openings.
FIG. 20 is an upper isometric view of another example of a blade guard and another example of a material pickup assembly.
FIG. 21 is a side elevation view of the blade guard and material pickup assembly of FIG. 20 .
FIG. 21A is a transverse cross-section of the assembly of FIG. 21 taken along line 21 A— 21 A.
FIG. 21B is a longitudinal vertical cross-section of the assembly of FIG. 21 taken along line 21 B— 21 B.
FIG. 21C is a detail of FIG. 21B .
FIG. 21D is an isometric view of FIG. 21C .
FIG. 22 is a side elevation view of the material pickup assembly of FIG. 20 .
FIG. 23 is a lower isometric view of the material pickup element of FIG. 20 .
FIG. 24 is a top plan view of the material pickup element of FIG. 20 .
FIG. 25 is a lower isometric view of a manifold and associated mounting components for use with the material pickup assembly of FIG. 20 .
FIG. 26 is a lower isometric view of the manifold of FIG. 25 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The following specification taken in conjunction with the drawings sets forth the preferred embodiments of the present inventions in such a manner that any person skilled in the art can make and use the inventions. The embodiments of the inventions disclosed herein are the best modes contemplated by the inventor for carrying out the inventions in a commercial environment, although it should be understood that various modifications can be accomplished within the parameters of the present inventions.
In accordance with several aspects of the present inventions, a waste containment system and method are provided for abrading, cutting or coring machines. While the description herein will be directed primarily to cutting machines, and while the preferred embodiments will be described with respect to applications to concrete saws, it should be understood that the inventions can be applied to any number applications other than concrete saws and other cutting machines. The concepts are applicable to other machines in a manner similar to how they would be applied to concrete saws as described herein. For example, the high and low vacuum openings on a material pickup element can be applied to any number applications, while they are especially pertinent to those where the amount of vacuum is limited or fixed. As another example, the separation receptacle can take any number of configurations given the concepts described herein. Moreover, other aspects of the inventions described herein can be used in any number of applications.
A waste containment system and method on a concrete saw in accordance with various aspects of the present inventions provide an efficient and reliable apparatus and method for limiting or entirely removing any waste material created or generated while cutting concrete. The system and method removes a substantial amount of water or other coolant produced during the cutting process. The vacuum used to remove the slurry can be easily generated through the engine or other power plant on the saw without noticeably reducing its output. Waste material can be reliably removed from the vacuum system so as to reduce contamination or fouling of components, and to give an acceptable operating lifetime to the components. The system and methods can be implemented as a complete product or as individual components, such as in kit form. All parts can be made removable, and they can be used to retrofit many existing saws.
In accordance with one aspect of the present inventions, a concrete saw 300 ( FIG. 1 ) includes a frame or chassis 302 supporting an engine, shown schematically as 304 , for driving a saw blade 306 through a drive shaft 308 . The engine and the drive shaft, as well as other transmission components, also drive and power other components of the saw, as is known to those skilled in the art of concrete saws. The saw and saw blade can also be powered and driven by an electric motor, and all of the components on it can be driven or energized electrically.
The saw also includes a material pickup element in the form of a vacuum bar 310 to which is coupled a preferably 2 inch diameter vacuum hose 312 for removing a slurry of water and particulates created during cutting. Water is provided through a conduit (not shown) to the inside of the blade guard 314 to act as a coolant for the blade 306 . The particulates are typically bits of concrete both large and small produced during cutting. Other waste material will be produced using other equipment on different work surfaces, but many of the concepts described herein will be similarly applicable. The blade guard 314 is preferably similar or identical to a blade guard described in U.S. Pat. No. 5,564,408, and is supported by a blade guard mount 316 , shown in FIG. 1 configured for mounting on a saw such as that manufactured by Cushion Cut. The blade guard includes a top mounted handle 318 for ease of access.
The vacuum hose 312 extends as short a distance as possible to a slurry recovery and separation assembly 320 ( FIG. 2 ) for transporting the slurry from the vacuum bar 310 to the assembly 320 . The vacuum hose 312 is preferably raised as little as possible above the level of the vacuum bar 310 so as to use as little vacuum as possible raising the slurry to the level of the assembly 320 . The assembly 320 is preferably located on a side or a surface of the saw 300 different from the right side where the blade is located so as not to obstruct the view that the operator has of the cutting area.
Vacuum is created in the assembly 320 , and therefore through the vacuum hose 312 and in the vacuum bar 310 , through a vacuum generator 322 coupled to the assembly 320 through a vacuum hose 324 . The vacuum generator 322 is driven by the drive shaft 308 , as discussed more fully below, and is controlled by the revolutions per minute (rpm) of the drive shaft. Alternatively, where the saw is electrically powered, the vacuum generator could be driven by current from the saw motor.
Waste is removed from the assembly 320 through a waste pipe 326 through a pump 328 ( FIG. 12 ) operated by a motor 330 . The pump 328 is similar to that described in U.S. Pat. No. 5,564,408 but includes metal reinforcing on several of the moving parts of the pump. The motor 330 is preferably an electric motor driven by current developed in an alternator or generator on the engine 304 . The pump also preferably includes conventional flap valves to control flow and prevent back flow on each side of the pump.
The vacuum bar 310 , modified blade guard 314 , vacuum hose 312 , assembly 320 and the vacuum generator 322 may be factory installed or produced as components for a kit or for retrofit on existing saws. The remaining components of the saw are typical, and do not require enhancements or extraordinary modifications. Some of the other typical components of the saw are illustrated for context such as the display panel 332 and handles 334 . While enhancements can be made to the basic saw to further optimize the operation, for example with larger saw blades, it is not believed that such modifications are necessary for proper operation.
The blade guard support 316 ( FIGS. 1 , 6 and 7 ) is similar to that described in U.S. Pat. No. 5,564,408, and includes a spacer 336 having a width defining the spacing between the left plate 338 and right plate 340 , but also a depth 342 to provide more strength to withstand bending or buckling of the plates 338 and 340 . A mounting holster 344 accepts the support element of the saw for supporting the blade guard.
The vacuum bar 310 ( FIGS. 8 and 9 ) for picking up the slurry from around the saw blade and from grooves is similar to the vacuum bar described in U.S. Pat. No. 5,564,408 in the context of concrete saws. The vacuum bar is supported by the blade guard and held stationary relative to the blade guard by a mounting plate 346 through a mounting bolt (not shown). The position of the vacuum bar relative to the blade guard can be adjusted through the mounting bolt for adjusting the spacing between the bottom of the vacuum bar and the work surface. The preferred spacing for effective pickup of slurry from the work surface may depend on a number of factors such as the size of the vacuum bar and the number openings, as well as the vacuum developed at the vacuum bar and the surface makeup. The spacing will also depend on the uniformity of the work surface and how much large debris is created during cutting. For concrete, the spacing may be about 1/16 th (one-sixteenth) of an inch, and greater for asphalt.
The vacuum bar is also supported or stabilized by a left side wall 348 and a U-shaped internal blade guard wall 350 . The left side wall 348 is welded or otherwise mounted to the mounting plate 346 and to the top of the vacuum bar manifold 352 , as well as to the left vacuum tube 354 adjacent an inner side surface 356 . The right side and rear of the wall 350 are mounted to the top surfaces of the right vacuum tube 358 and manifold 352 , respectively. Part of the left side of the wall 350 is welded to the top of the left vacuum tube 354 , and a remainder extends between the right vacuum tube 358 and the left vacuum tube 354 ( FIG. 9 ). Various reinforcing walls can also be included. The vacuum coupling 360 is mounted to the top of the manifold 352 for accepting the vacuum hose 312 . The tail 362 of the vacuum bar extends rearwardly from the center of the manifold 352 . The left side vacuum tube 364 extends at an angle from the left vacuum tube 354 to the left side and toward the front, and the right side vacuum tube 366 extends to the right side from the right vacuum tube 358 and toward the front. The left side vacuum tube 364 joins the left vacuum tube 354 at a point forward of the manifold 352 in order to make room for other hardware on the saw.
As shown in FIGS. 8 and 9 , the vacuum bar 310 defines a housing beginning with the manifold 352 and having a plurality of housing walls such as the top 368 of the manifold, the bottom wall 370 of the manifold, and a front manifold wall 372 . The housing of the vacuum bar also includes a first housing wall 374 defining the right vacuum tube 358 and comprising a top wall 376 , a left side wall 378 , a right side wall 388 , and a bottom wall 382 , and closed off by a preferably removable end cap ( FIG. 8A ). The first housing wall 374 is shown having a square, longitudinally extending configuration or cross-section defining a channel 390 closed by the end cap on one end and joining the manifold at the other end adjacent the forward wall 372 . Other configurations are possible, but a square cross-section is preferred to enhance pickup and transport of the slurry. The other vacuum tubes are also preferably square in cross-section.
The bottom wall 382 includes a plurality of opening walls defining a plurality of apertures passing through the bottom wall 382 to permit a pressure differential across the bottom wall between the channel 390 and the outside of the tube 358 when vacuum is applied to the vacuum coupling 360 . The plurality of apertures includes at least one low vacuum aperture 392 and at least one high vacuum aperture 394 . The high vacuum aperture picks up most if not all of the slurry in its region and the low vacuum aperture focuses, collects concentrates or aligns the slurry so that it can be more easily picked up by a high vacuum aperture, typically a different high vacuum aperture. Some pickup may occur with the low vacuum apertures. It is believed that the low vacuum apertures center or bring in fluid from both sides of the vacuum bar so that it can be picked up by a high vacuum aperture following behind. For example, a trailing high vacuum aperture 396 generally aligned with the preceding low vacuum apertures 392 will pickup the slurry gathered by the apertures 392 . The trailing high vacuum aperture 396 is formed in the bottom wall 370 of the manifold. Additionally, though not necessarily, a side high vacuum aperture 398 formed in the bottom surface or wall 400 of the right side vacuum bar 366 may also pickup slurry gathered by the low vacuum apertures 392 . It should be noted that aperture 398 will also pickup water splashed away from the saw blade, which would not typically include any particulates generated during cutting.
Using high vacuum and low vacuum apertures helps to conserve vacuum pressure or minimize the loss of vacuum through larger openings, especially where the amount of vacuum available may be limited by the size of the saw, available horsepower, and the like. They are also helpful, for a given size of saw, where larger blades are used in place of smaller blades. With a larger blade, the vacuum bar 310 is longer in overall dimension, preferably extending at least to the front of the blade guard if not further forward. For a given saw, a 30 inch blade would preferably include a vacuum bar 310 A ( FIG. 18 ) that was about 44 or 45 inches long, whereas the suction bar shown in FIGS. 8 and 9 was designed for a 16 inch blade and is about 27 or 28 inches long. A 26 inch blade would preferably include a vacuum bar 310 B ( FIG. 19 ) that was about 38 or 40 inches long. Additionally, having both low and high vacuum apertures allows positioning of the high vacuum apertures at locations of high slurry and/or water production, and positioning of low vacuum apertures elsewhere where high vacuum is not as important. Nonetheless, the low vacuum apertures still help to collect the slurry to be picked up by a following or trailing high vacuum aperture.
In one preferred aspect of the present inventions, the low vacuum apertures are round or similarly shaped holes having walls 402 , 404 and 406 . The holes are preferably formed straight through the bottom wall 382 of the housing 374 perpendicular to the surface of the housing. However, the configurations of the holes can be different, as well as different from each other, in size, shape, positioning and orientation. For example, the low vacuum holes can be arranged in a series such as those shown in FIG. 9 , aligned with one another, and also aligned with the end of the high vacuum aperture 394 . The first one or several low vacuum holes, for example, can be the same size while following holes toward the rear of the vacuum bar can be larger in size, and therefore higher in vacuum. Conversely, they can decrease in size in the same direction. Additionally, the apertures can be placed other than in the center of the bottom wall 382 .
In another preferred aspect of the present inventions, the high vacuum apertures are extended slots defined by substantially straight walls 408 joined by substantially circular end walls 410 . The high vacuum apertures are also preferably formed straight through the bottom wall 382 of the housing 374 perpendicular to the surface. As with the low vacuum apertures, the high vacuum apertures can be different as well as different from each other in size, shape, position and orientation, and may vary in size from one end to the other of an individual slot.
The apertures, such as the high vacuum apertures, can be curved such as the high vacuum apertures 396 in the manifold 352 . They also can have other shapes. The aperture 396 extends almost the entire length of the manifold and curves toward longitudinal center line of the manifold. Additionally, as can be seen in FIG. 9 , a high vacuum aperture such as 396 can be formed from two or more openings, including 398 . A second high vacuum aperture 412 may be formed from a long slot and two oppositely extending short slots. Additional high vacuum apertures 414 and 416 are preferably formed in the bottom wall 370 of the manifold and the bottom wall of the tail 362 of the vacuum bar, respectively, preferably aligned with the plane of the saw blade to remove slurry not only from the work surface but also the groove just cut.
The high vacuum aperture 414 is formed from a slot in the bottom 370 in the manifold and from a slot 418 ( FIG. 8 ) formed in a vertical forward wall 372 of the manifold. As can be seen, a high vacuum aperture can be formed in two different surfaces of the vacuum bar. The slot 418 can be formed as its own high vacuum aperture positioned directly behind saw blade to pickup material thrown up by the saw blade. However, it is believed that a continuous high vacuum aperture formed by the slot 418 and the slot 414 is more effective at picking up slurry immediately behind the saw blade. The slot 418 can be wider than the other high vacuum slots, as can other high vacuum slots immediately behind the blade, or they can be the same width.
The first housing wall 374 may also include an additional high vacuum aperture 418 at a forward portion 420 of the first housing 374 . The aperture 418 would be the forward-most aperture on the right side of the vacuum bar to be able to pickup water or slurry from the work surface. In the preferred embodiment, three low vacuum apertures 422 are positioned close behind and aligned with the high vacuum aperture 418 .
In the preferred embodiment, the left vacuum bar 354 forms a second housing element 424 in fluid communication with the manifold and the first housing wall 374 , extending forward of the manifold and slightly divergent from the first housing wall 374 . The second housing element 424 also preferably includes a forward high vacuum aperture 426 to be the forward-most high vacuum aperture on the left side of the vacuum bar. It also includes a set or series of low vacuum apertures 428 preferably aligned with and rearward of the high vacuum aperture 426 . An additional high vacuum aperture 430 may be formed between the low vacuum apertures 428 and the manifold 352 .
As can be seen in FIG. 9 , the high vacuum and low vacuum apertures can alternate and can be aligned with respect each other, preferably in the general direction of travel of the vacuum bar. The openings are preferably distributed over the vacuum bar so as to take advantage of the forward or backward motion of the saw. The different openings promote more even flow of the slurry relative to the vacuum bar and conserve vacuum pressure. The high vacuum and low vacuum apertures may alternate between a single large opening and a series of small openings, again followed by a large opening. The actual distribution, configuration and arrangement of the different apertures may be determined by a fluid dynamics computer program based on various input parameters, including available vacuum or suction, viscosity, desired flow rates, and the like. The openings are also given, typically, and the system works iteratively to develop possible solutions. While most of the apertures open downwardly from the bottom of the vacuum bar toward the work surface, at least one aperture 414 includes a portion (slot 418 ) that extends vertically, opening or facing other than downwardly. In one preferred embodiment, the low vacuum apertures are 0.125 in. in diameter (less a few thousandths of an inch for a powder coating on the vacuum bar) and separated from each other by about 0.750 in. They are preferably arranged in series of three. The width of the high vacuum apertures is preferably 0.125 in., and their length may range from less than an inch to several inches, depending on the length of the vacuum bar. The vacuum bar for a 16 in. saw blade can have high vacuum aperture lengths up to four or five inches or more for vacuum developed with a conventional saw with the system described herein.
FIG. 8A shows a bull-nosed end cap 432 for closing off the forward ends of the left and the right vacuum tubes and the rearward end of tube 362 . The bull nose shape includes curved surfaces 434 for more easily negotiating or riding over pebbles or other objects which may be in the line of travel, such as created during cutting. The end caps are removable for easier cleaning of the vacuum bar.
The slurry recovery and separation assembly 320 ( FIGS. 10–13 ) separates the air from the water coming from the vacuum hose 312 , and therefore removes abrasive material from the air. Other damaging materials may also be present in the slurry, which are preferably removed from the air. The assembly 320 preferably includes a fluid-tight receptacle, container, canister or tank 436 for receiving a combination of the air and slurry, and including at least two vertically extending walls, such as right side wall 438 and front exit wall 440 . The two walls meet and join at a vertically extending 90 degree angle 442 so that the potential for the air and slurry within the tank 436 to rotate or create a cyclone-type motion is reduced. The left side wall 444 , similar in shape to the right side wall 438 , also extends vertically and joins the front exit wall 440 at a vertically extending angle 446 . Both of the left and right side walls meet and join a back inlet wall 448 at respective vertically extending angles or corners 450 and 452 , respectively. The tank 436 is closed by a top or cover 454 which joins the respective side walls at 90 degree angles at a support flange 456 extending around the perimeter of the tank. It is removable for easy cleaning of the tank. The tank 436 preferably does not have a flat, horizontal bottom, to reduce splashing. The remaining walls between the left and right side walls are generally square or rectangular, join the respective side walls at 90 degree angles, preferably, but are arranged more or less horizontally or vertically as a function of location relative to an inlet or an outlet.
The back inlet wall 448 extends vertically a substantial portion of the height of the tank 436 . The bottom joins a first shelf plate 458 at an angle 460 of approximately 100 degrees for allowing liquid to flow down the first shelf plate 458 . The first shelf plate 458 slopes to a lower shelf plate 462 . The first shelf plate 458 and the lower shelf plate 462 join at an angle 464 of approximately 200 degrees to minimize upward splashing of slurry, and to move slurry down to the bottom of the lower shelf plate 462 where it collects. The lower shelf plate 462 ends at and is supported by a pump support plate 464 and joins a slurry outlet plate 466 at an angle 468 of approximately 30 degrees, a small acute angle. This angle is relatively small so as to effectively retain the slurry in the relatively narrow bottom until it is pumped out by the pump 328 through a slurry outlet 470 located close to and connected to the pump by a short tube of about several inches. The slurry outlet plate 466 extends upwardly and rearwardly to approximately the same level as angle 464 , where it joins a riser plate 472 at an angle 474 of approximately 223 degrees. The angle 474 is preferably greater than 180 degrees so as to increase the volume of the mid-level portion of the tank, or that portion of the volume of the tank between angle 474 and the top of the riser plate 472 and the back inlet wall 448 , while still presenting a splash plate or wall tending to keep the slurry and any excess water between plates 462 and 466 . The riser plate 472 is preferably at about a 15 degree angle from the vertical to provide a vertically extending wall for minimizing splashing while still providing an increasing volume in the upward direction and interrupting any direct line of air flow from the inlet to the air outlet. The riser plate 472 extends away from the back inlet wall 448 to allow air to travel more easily upward and away from the slurry.
The riser plate 472 joins an upper shelf plate 476 at an angle 478 of approximately 249 degrees. The upper shelf plate 476 extends forward to vertical front exit wall 440 where they join at an angle 480 . The upper shelf plate 476 provides the base portion of the upper approximate one-third of the tank, measured vertically. The upper third of the tank preferably contains almost all air and very little moisture or slurry. The intermediate approximate one-third of the tank, measured vertically, will have a substantial portion of air and some water or slurry. The lower one-third, measured vertically, preferably has almost exclusively slurry. The depth of the slurry is preferably about 3 to 3½ inches.
The tank includes an inlet 482 for receiving a combination of air and slurry from the vacuum hose 312 and allowing the combination of air and slurry to flow into the tank. The inlet passes through the back inlet wall 448 . The inlet 482 is preferably a relatively rigid tube or pipe 484 and extends a substantial distance from the wall 448 toward the riser plate 472 to a 90 degree elbow 486 . The elbow 486 terminates in a wall 488 defining an opening 490 preferably facing directly downward toward lower shelf plate 462 for allowing the slurry to drop straight down. The opening 490 is preferably positioned below the upper shelf plate 476 so that there is no direct line of air flow between the opening 490 and the air outlet. The opening 490 as well as the rest of the inlet 482 are preferably two inches in diameter and may pass an approximately 3:1 ratio of air to slurry by cross-sectional area at about 200 cubic feet per minute. The opening 490 is positioned significantly below the upper shelf plate 476 so that the water and slurry are input well below the upper third of the tank. The inlet 482 is preferably centered between the left and right side walls. Additionally, the slurry is preferably input closer to the riser plate 472 than to the inlet plate 448 so that the slurry travels as little as possible before reaching the bottom of the tank and the slurry outlet 470 . The opening 490 is preferably high enough above the slurry level that vacuum is still created in the vacuum line 312 without creating turbulence on the surface of the slurry at the bottom of the tank, while at the same time minimizing the height that the slurry must be raised from the suction bar to the inlet 482 .
A second, air outlet 492 removes air from the tank 436 thereby creating a vacuum within the tank, which creates a vacuum within the vacuum hose 312 for producing suction in the suction bar 310 . The air outlet 492 is preferably centered between the side walls and located close to the air outlet wall 440 and a significant distance from the slurry in the bottom of the tank. The air outlet is not located on any line or plane of symmetry other than between the two side walls thereby reducing the possibility that air being removed from the tank is part of a channel of air flow. The air travels a significant distance through the tank to reach the outlet, and does not have a direct line of travel between the opening 490 and the outlet 492 . The outlet 492 includes a wall 494 for defining an opening 496 which is preferably flush with the top 454 of the tank.
The separation tank promotes organized control of the slurry and disorganized or uncontrolled flow of air within the tank. The irregular surfaces and discontinuous walls in the tank reduces cyclone-type fluid flow within the tank which would tend to keep moisture and particulates carried in the air. The inlet is placed close to the slurry or other material outlet and close to a wall to help contain the material flow. Residual splashing is minimized as much as possible by interrupting any straight or parabolic air path and any air flow channels, and reducing symmetries of surfaces within the tank, while encouraging a gentle gradient of air flow from the area of the inlet portion of the tank to the outlet portion of the tank. Additionally, it is preferred to minimize the amount of directional change of the air and slurry coming out of the opening 490 . It is also preferred to place the inlet opening far enough away from any given surface to minimize funneling or channeling of air upward past the opening 490 . One measure of one preferred inlet position is to have a relatively large change in cross-sectional area going from the opening 490 into the open tank and reducing the velocity of the air and slurry mixtures. Additionally, a large total volume for the tank is preferred.
Some exemplary approximate dimensions for the separation tank have the width equal to about 9 and ½ in. and the overall length about 27 inches. The inlet wall is about 12 inches high and height from the pump support plate 464 to the top of the tank is about 18 inches. The plate 440 is about five inches high, the plate 476 about 13 inches long and the plate 472 about eight inches long. The plate 466 is about four inches long and the plate 462 about eight inches long. The plate 458 is about seven inches long. The length of the inlet 482 from the center of the opening 490 to the outer most point of the pipe outside the tank is about 13 and ½ inches. These dimensions give a tank having a low height, large volume and a relatively large transition from the inlet pipe to the tank.
A level indicator or overflow alarm (not shown) can be included to indicate when the level of slurry reaches a selected level. Other indicators and safety features can be included as desired to make easier becoming familiar with a machine and for using the machine.
Power to the pump 328 is provided by a sealed conductor 498 extending from a fast hook-up and disconnect junction and switch box 500 , mounted at the inlet panel 448 , to the pump 328 . The conductor extends through a sealed opening in the panel 466 . A shut-off switch 502 can be used to start or stop the pump.
A mounting plate 504 ( FIGS. 13 and 14 ) can be fastened to the side of the saw so that the separation tank and pump assembly can be removably mounted to the saw through hooks or other brackets 506 . The plate and hooks are preferably configured to insure that the separation tank and pump assembly maintain a center of gravity for the tank.
The vacuum generator 322 includes a housing 508 ( FIG. 1 ) for containing an impeller or fan 510 ( FIGS. 15–17 ) for creating a vacuum in the tank. The fan may be a Breuer Electric Mfg. Tornado with a number 12692 impeller capable of generating at least 180 to 184 cubic feet per minute of flow, or more, at 16,500 rpm through a two inch diameter orifice. The fan is preferably rated for fifty-one inches of static water lift. The fan chamber part number 12642 and the fan chamber plate part number 11237 are also included. The fan is driven off of the saw blade drive shaft 308 through a pulley 512 which drives a second pulley 514 , which in turn drives the shaft 516 of the fan. The fan exhaust 518 is directed into the housing 508 for cooling the high speed bearings and/or components of the saw.
The fan and two idlers (one for each drive belt, not shown) are each supported by two high speed, long life and lifetime lubricated bearings mounted, supported and protected on the saw frame by suitable supports. The bearings are preferably rated for at least the 16,500 rpm operating conditions, and preferably higher. The preferred bearings are SKF Mfg. number 6202-2Z/C3HT bearings rated for 29,000 rpm.
The tool guard such as the blade guard 314 includes a water supply conduit or tube 520 for projecting or spraying fluid onto the saw blade ( FIG. 17 ). The water is directed toward the tool at an angle different than 90 degrees. For example, the water can be directed backward toward the rotationally-advancing side of the blade. Directing the water backward relative to the rotation of the blade reduces the amount of water thrown forward of the blade. Consequently, the amount of water to be picked up at the front of the blade is reduced. In one preferred embodiment, the water is directed backward at an angle 522 of about three degrees from a line 524 perpendicular to the blade.
By including a vacuum generator on the saw driven by the saw engine or other power supply, the components of the saw can still be part of a self-contained unit. The vacuum generator can operate and produce the desired vacuum under a number of different conditions, such as different saw blade sizes, cutting speeds and the like. The vacuum generator can also be easily mounted on and removed from the saw along with the other slurry containment components. The separation tank, the suction bar, the pump assembly, blade guard and vacuum hose can be easily installed on existing saws and removed if desired. The components can be made available in kit form or installed at the factory.
The waste containment and separation system can be used in other applications beyond concrete saws. Wall saws, grinding heads and core drills also produce particulates that can be contained through application of one or more of the concepts described herein. For example, using high and low vacuum apertures in a pickup element conserves vacuum pressure and permits a selective arrangement of high vacuum pickup locations. Vacuum generators can also be driven off of the drive elements of the tools, if desired. Additionally, the concepts developed for separating air from a slurry for maintaining the integrity of the vacuum generator can be applied to other applications. The amount of feedback of damaging particulates or other contaminants can be reduced, thereby extending the life of many components. Filters may not be necessary, as they reduce the vacuum and produce drag.
An example of a tool guard and material pickup assembly 600 ( FIG. 20–21 ) includes a tool guard 602 , which in the present example is a blade guard for a saw blade, such as that used in concrete saws, flat saws and other cutting or processing equipment. The assembly also includes a material pickup assembly 604 . The material pickup assembly 604 in the present example serves not only to pickup material produced during the cutting operation, but also to support the blade guard 602 .
The blade guard extends partly about the saw blade 606 as the saw blade cuts concrete or other work material. The blade guard 602 defines a volume within which the saw blade operates as the saw blade cuts into the concrete. The blade guard includes at least a first wall 608 and a second wall 610 ( FIG. 21 ) extending on opposite sides of the saw blade and having respective inside surfaces 612 and 614 facing each other and extending on respective sides of the saw blade. The first wall 608 , and preferably the second wall 610 , include respective edge portions 616 substantially defining the lower-most portions of the blade guard, and which are adjacent but spaced apart from the concrete during operation. The blade guard also preferably includes one or more transverse extending rim or spacer walls 618 spanning and separating the first and second walls 608 and 610 , respectively, and for completing the enclosure defined by the blade guard. The blade guard may include a handle 620 for lifting the blade guard from the material pickup assembly 604 . The blade guard has one or more fluid supply tubes 622 , for supplying fluid such as water to lubricate and cool the saw blade. The tubes 622 receive fluid through appropriate supply lines, as would be known to those skilled in the art. The saw blade is driven by the saw in a manner similar to that described previously, and the assembly 600 moves with the saw in a similar manner, as known to those skilled in the art.
Considering the blade guard in this example in more detail with respect to FIG. 21 , the inside surface of the first wall 608 includes at least one second wall, such as the water channel 624 , contacting the inside surface of the first wall 608 and extending laterally from the inside surface in the same direction that the saw blade is spaced from the first wall, and extending longitudinally in a direction away from the edge portion 616 . In the example shown in FIG. 21 , the work surface is relatively horizontal and the first wall 608 extends substantially vertically upward from the edge portion 616 , and the second wall portion slopes downwardly from a point 626 closer to the saw blade to a point 628 further away from the saw blade. The second wall portion in the example shown in FIG. 21 is fixed, bonded, riveted and/or welded to the inside surface of the first wall 608 and includes a rectangular flange portion extending to the interior of the blade guard from the inside surface of the first wall 608 . The rectangular flange portion promotes water flow, with the assistance of gravity, downwardly and closer to the lower edge 616 , and preferably it channels the fluid to a second water channel 630 having a steeper slope than the first water channel 624 . The rectangular flange portion of the first water channel 624 also limits fluid flow along the inside surface of the first wall 608 and channels that fluid to the second water channel 630 . In the example shown in FIG. 21 , the water channel 624 is L-shaped and has the vertical leg mounted to the first wall and the second leg extending into the interior of the blade guard. It is positioned at an approximate vertical midpoint in the blade guard. The second water channel extends from the second point 628 to a point 632 adjacent the lower edge 616 , where the second water channel terminates at a line spaced apart from the adjacent vertical wall 634 to form an opening 636 feeding into the material pickup assembly, as described more fully below.
In the example shown in FIG. 21 , the first water channel 624 joins near the point 628 with a preferably mirror image water channel 638 contacting and fixed to the second wall 610 , preferably having the same shape, size and slope as the first water channel 624 , joining the first water channel through a joining wall 640 . The joining wall 640 preferably begins approximately 1 in. outboard of the perimeter of the saw blade and extends to the outer point 628 . The first and second water channels are preferably joined to or continuous between each other at the point 628 , and the second water channel preferably spans the space between the first and second walls 608 and 610 , respectively. The first and second water channels also reduce the spray of fluid and material upward and toward the walls 618 , and thereby channel the fluid downward.
A third water channel 642 has a smaller slope than the first channel 624 and extends from a point adjacent the opening 636 slightly upwardly and in the direction of the blade to a point 644 . The third water channel shown has a U-shaped cross section (as seen in FIGS. 21C & 21D ) and also channels fluid to the opening 636 and reduces the amount of fluid reaching the lower edge 616 . The first, second and third water channels are positioned on that part of the blade guard which receives the spray of material and fluid from the saw blade. The blade guard and material pickup are reversible to accommodate a down cut saw and an up cut saw. The opening 645 in the first side of the blade guard permits viewing of the blade when positioned on the outside of the saw and accommodates the blade shaft when positioned adjacent the saw. A substantially similar opening is formed in the second side 610 . The structure on the first side of the blade guard is preferably symmetrical with that on the opposite side. The water channels can take any number of shapes, sizes and configurations.
A fourth water channel 646 , and a mirror image water channel on the opposite side of the blade, channel water to a fifth water channel 648 extending downwardly and away from the blade to an opening 650 , which receives fluid for transfer to the material pickup assembly. A sixth water channel 652 has a greater slope than water channel 642 , as it is closer to the blade. The sixth water channel 652 also channels fluid to the opening 650 . The water channels have similar structures and functions. The blade guard also preferably includes deflector plates 654 , 656 and 658 having a structure and function similar to that of the diagonal plate in Bassols, U.S. Pat. No. 5,564,408.
The example of FIGS. 20 and 21 also includes a blade guard support, which in this example also serves as the vacuum assembly 604 . The blade guard support includes at least one and preferably three rolling elements, casters or wheels 660 for supporting the blade guard support on the work surface. The wheels are adjustable vertically to adjust the relative spacing of the blade guard support, and in the present example the vacuum assembly, from the work surface. The wheels 660 support the blade guard support at the desired spacing from the work surface even when the blade guard is removed and then replaced. Re-adjustment of the blade guard upon replacement is not necessary. The blade guard support includes one or more walls 662 extending upward from the area where the lower edges 616 of the blade guard rest. The walls 662 help to support the blade guard. Mounting plates 664 include slots 666 for receiving fasteners, bolts 668 or other means ( FIG. 21 ) for fixing the blade guard to the blade guard support. The blade guard fits within the enclosure defined by walls 662 and mounting plates 664 .
In the present example shown in FIGS. 20 and 21 , the assembly includes a material pickup assembly in the form of a vacuum assembly 604 having, in this example, first and second vacuum ports 670 and 672 at the two ends of the assembly coupled to vacuum manifolds 674 and 676 , respectively. First and second vacuum tubes 678 and 680 , respectively, extend almost the entire length of the vacuum assembly, and the ends of the vacuum tubes extend over and engage respective vacuum ports 682 on the manifolds ( FIG. 26 ). Each vacuum tube is preferably a square aluminum tube having a three quarter inch internal dimension, and a plurality of vacuum holes 684 extend through the bottom walls of the tubes. Each vacuum tube includes a closure at approximately the center point thereof so the fluid does not flow from one half of the tube to the other half. The vacuum assembly also includes an aluminum wear plate 686 forming the bottom surface of the vacuum bar and having a plurality of vacuum holes 688 coaxial with and having the same diameter as the vacuum holes 684 .
Each manifold 674 and 676 preferably includes a substantially identical aluminum manifold plate 690 ( FIGS. 25 & 26 ). Each manifold plate is covered on the bottom by the wear plate 686 . The three transverse vacuum ports 692 open into a transverse channel 694 . The channel 694 flows into a longitudinal channel 696 and out through a first opening through a coupling plate 698 which flows into the vacuum port 670 . The first opening is preferably curved and is formed by walls which are preferably smooth and continuous, so as to minimize flow eddies and accumulation of debris.
Each vacuum tube is coupled to its port 682 , which flows into respective second and third channels 700 and 702 , which are preferably substantially identical to each other. Each channel extends away from the respective tube and inward toward the center of the manifold, and then flows upwardly through the coupling plate 698 and into the vacuum port 670 . The flow from the channels combine in the coupling plate 698 .
The material flow from the water channels inside the blade guard flow downward to the wear plate and through an opening in the mounting plate 664 and through a fourth opening 704 in the manifold. The fourth opening flows into a fourth channel in the manifold. The fourth channel extends outwardly away from the blade and upwardly toward the coupling plate 698 , after which the flow joins the material flow from the other channels in the vacuum port 670 .
Having thus described several exemplary implementations of the invention, it will be apparent that various alterations and modifications can be made without departing from the inventions or the concepts discussed herein. Such operations and modifications, though not expressly described above, are nonetheless intended and implied to be within the spirit and scope of the inventions. Accordingly, the foregoing description is intended to be illustrative only. | Abrading and cutting devices such as saws include waste containment systems and methods to improve removal of slurry or other contaminants from a work area during operations, and separation of slurry from a carrying medium such as air. A blade guard includes fluid channels, and may be removable from a blade guard carriage. The carriage may be used to minimize any need to readjust the blade guard position when the blade guard is returned to the carriage for further use. A vacuum bar may be included on the carriage. A vacuum pickup assembly may be used with a blade guard, and the vacuum assembly may include separate and/or different vacuum pickup configurations. | 1 |
This application is a 371 of PCT/GB94/01803 filed Aug. 17, 1994.
FIELD OF THE INVENTION
The present invention relates to certain flavonoids which have been found to have anxiolytic properties (i.e. anxiety reducing) without corresponding depression of the central nervous system which is commonly also found in known sedatives such as benzodiazepines.
BACKGROUND OF THE INVENTION
Some compounds of the invention are novel; other compounds are known but no pharmaceutical uses have previously been described.
Flavone is a known compound which is described in the Merck Index (entry 4030). Chrysin (2261) and apigenin (763) are other known flavonoids. Chrysin has been described as having binding properties for benzodiazepine receptors and anticonvulsant properties in Medina J. H. et al. Biochem. Pharmacol; 40:2227-2232, 1990. This reference also suggests that chrysin may possess myorelaxant (i.e. muscle relaxant) action.
Flavone, 2-phenyl-4H-1-benzopyran-4-one has the formula ##STR1##
Chrysin is 5,7-dihydroxyflavone
Apigenin is 4', 5,7- trihydroxyflavone.
SUMMARY OF THE INVENTION
The present invention relates to a method of treatment of anxiety in a patient which comprises administering to the patient an effective non-toxic amount of a flavonoid compound of general formula (I): ##STR2## where R 1 , R 2 , R 3 and R 4 , R 5 and R 8 are independently selected from H, OH, R, NO 2 , halo, OR, NH 2 , NHR, NR 2 , COOR, COOH, CN, or a sugar group;
R 6 and R 7 are both H, or R 6 and R 7 together form a single bond;
R is C 1-6 alkyl or alkenyl;
or the administration of an effective non-toxic amount of a biflavonoid which is a dimer of a compound of general formula (I) and wherein R 1 to R 8 and R have the meanings given for general formula (I).
It is found that the compounds of the present invention have anxiolytic properties without the associated depression of the central nervous system (e.g. sedative and muscle relaxant effects) commonly found with benzodiazepines. This may allow patients to be treated for anxiety without inducing sedative or myorelaxant side-effects.
It is found further that compounds of the present invention may not show an anti-convulsant activity commonly found with benzodiazepines.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a graph illustrating ambulatory locomotor activity counts in mice during a five minute test session, twenty minutes after intraperitoneal (i.p.) injection with diazepam (DZ) or chrysin (CHRY);
FIG. 2 is a graph illustrating test results of mice given a five minute test in the elevated plus-maze, twenty minutes after i.p. injection with DZ or CHRY;
FIG. 3 is a graph illustrating test results of mice given a five minute test in the elevated plus-maze, twenty minutes after i.p. injection with vehicle (VEH), CHRY or CHRY plus RO 15-1788 administered ten minutes before chrysin;
FIG. 4 is a graph illustrating the test results of mice given a five minute test in a holeboard, twenty minutes after i.p. injection with DZ or CHRY;
FIG. 5 is a graph illustrating test results of mice in a wire test, twenty minutes after i.p. injection with DZ or CHRY;
FIG. 6 is a graph illustrating test results of mice given a five minute test in the elevated plus-maze and ambulatory activity in mice given a five minute test, twenty minutes after i.p. injection with vehicle and apigenin;
FIG. 7 is a graph illustrating test results of mice given a five minute test in the holeboard, and performance to grasping the wire test, twenty minutes after i.p. injection with vehicle and apigenin;
FIG. 8 is a graph illustrating noradrenaline levels in locus coeruleus nucleus after a session of immobilization stress alone or with pre-treatments;
FIG. 9 is a graph illustrating test results of mice given a five minute test in the elevated plus-maze and ambulatory activity in mice given a five minute test, twenty minutes after i.p. injection with vehicle and flavone;
FIG. 10 is a graph illustrating test results of mice given a five minute test in the elevated plus-maze, twenty minutes after i.p. injection with vehicle and a mixture of brominated flavone;
FIG. 11 is a graph illustrating test results of mice given a five minute test in the elevated plus-maze, twenty minutes after i.p. injection with 2'-chlorinated chrysin;
FIG. 12 is a graph illustrating test results of mice given a five minute test in the elevated plus-maze, twenty minutes after i.p. injection with 2'-fluorinated chrysin;
FIG. 13 is a graph illustrating test results of mice given a five minute test in the elevated plus-maze, twenty minutes after i.p. injection with 6,8-dibromochrysin;
FIG. 14 is a graph illustrating test results of mice given a five minute test in the elevated plus-maze, twenty minutes after i.p. injection with 7-bromoflavone;
FIG. 15 is a graph illustrating ambulatory locomotor activity counts in mice during a five minute test session, twenty minutes after i.p. injection with a mixture of brominated flavones;
FIG. 16 is a graph illustrating ambulatory locomotor activity in mice during a five minute test session, twenty minutes after i.p. injection with a mixture of 2'-chlorinated chrysin;
FIG. 17 is a graph illustrating ambulatory locomotor activity in mice during a five minute test session, twenty minutes after i.p. injection with a mixture of 2'-fluorinated chrysin;
FIG. 18 is a graph illustrating ambulatory locomotor activity in mice during a five minute test session, twenty minutes after i.p. injection with a mixture of 6,8-dibromoflavin; and
FIG. 19 is a graph illustrating the results of NMR analysis of a mixture of brominated flavones and identifying 7-bromoflavone as an active ingredient.
DETAILED DESCRIPTION OF THE INVENTION
The compounds of general formula (I) wherein R 1 , R 2 , R 3 , R 4 and R 5 may independently be H, OH or halo (including F, Cl, Br or I) are preferred. The preferred halo substituent is Br, F or Cl.
The following compounds of general formula (I) are particularly preferred wherein R 1 , R 3 , and R 5 may be hydroxy. Also wherein R 1 , and R 3 are hydroxy and R 5 is halo. Alternatively wherein R 3 is hydroxy and R 1 is hydrogen, or wherein R 3 and R 1 are both hydroxy is preferred. More preferably R 2 and R 4 are both halo. More preferably R 5 is OH or halo.
When R 5 is halo it is particularly preferred that the compounds of general formula (I) are substituted at the 2' position.
The compounds of general formula (I) which are flavone, chrysin, apigenin and the derivatives 2'-chlorochrysin, 2'-fluorochrysin, 6,8-dibromochrysin and 7-bromoflavone are particularly preferred.
Compounds where R 6 and R 7 together form a single bond are flavone derivatives, whereas compounds where R 6 and R 7 are both H are flavonone derivatives.
The sugar group may be any of the known sugars, including monosaccharides, disaccharides and polysaccharides; and may in particular be glycosyl, galactopyranosyl or mannopyranosyl.
The biflavonoid is a dimer of two covalently bonded moieties which are each of general formula (I) as set out above. Bonding between the two moieties generally occurs at the 3'-position of one moiety and the 8-position of the other moiety. The preferred biflavonoid has general formula (II) wherein R 1 to R 8 and R have the same meanings as for general formula (I). ##STR3##
The compounds of general formula (II) wherein R 1 , R 3 and R 5 in each of the dimer moieties of general formula (I) are hydroxy or methoxy are preferred.
The compounds of general formula (II) wherein the compounds are amentoflavone, ginkgetin or isoginkgetin are preferred.
Pharmaceutical formulations include at least one compound of general formula (I) or (II) together with at least one pharmaceutically acceptable carrier or excipient. Each carrier must be "pharmaceutically acceptable" in the sense of being compatible with the other ingredients of the formulation and not injurious to the patient.
It should be understood that the flavonoid compounds of the present invention can be administered in the form of pharmaceutically acceptable salts or esters thereof. Salts are usually acid addition salts (e.g. with hydrohalogen acids) or acceptable metal salts (e.g. Na, Ca, Mg).
Formulations include those adapted for oral, rectal, nasal, vaginal and parenteral (including subcutaneous, intramuscular, intravenous and intradermal) administration. The formulations may conveniently be presented in unit dosage form and may be prepared by any methods well known in the art of pharmacy. Such methods include the step of bringing into association the active ingredient with the carrier which constitutes one or more accessory ingredients. In general, the formulations are prepared by uniformly and intimately bringing into association the active ingredient with liquid carriers or finely divided solid carriers or both, and then if necessary shaping the product.
Formulations of the present invention adapted for oral administration may be presented as discrete units such as capsules, cachets or tablets each containing a predetermined amount of the active ingredient; as a powder or granules; as a solution or a suspension in an aqueous or non-aqueous liquid; or as an oil-in-water liquid emulsion or a water-in-oil liquid emulsion. The active ingredient may also be presented as a bolus, electuary or paste.
A tablet may be made by compression or moulding, optionally with one or more accessory ingredients. Compressed tablets may be prepared by compressing in a suitable machine the active ingredient in a free-flowing form such as a powder or granules, optionally mixed with a binder (e.g. povidone, gelatin, hydroxypropylmethylcellulose), lubricant, inert diluent, preservative, disintegrant (e.g. sodium starch glycollate, cross-linked povidone, cross-linked sodium carboxymethylcellulose) surface-active or dispersing agent. Moulded tablets may be made by moulding in a suitable machine a mixture of the powdered compound moistened with an inert liquid diluent. The tablets may optionally be coated or scored and may be formulated so as to provide controlled release of the active ingredient therein using, for example, hydroxypropylmethylcellulose in varying proportions to provide the desired release profile.
Formulations for rectal administration may bepresented as a suppository with a suitable base comprising for example cocoa butter or a salicylate.
Formulation for vaginal administration may be presented as pessaries, tampons, creams, gels, pastes, foams or spray formulations containing in addition to the active ingredient such carriers as are known in the art to be appropriate.
Formulations for parenteral administration include aqueous and non-aqueous isotonic sterile injection solutions which may contain anti-oxidants, buffers, bacteriostats and solutes which render the formulation isotonic with the blood of the intended recipient; and aqueous and non-aqueous sterile suspensions which may include suspending agents and thickening agents. The formulations may be presented in unit-dose or multi-dose sealed containers, for example, ampoules and vials, and may be stored in a freeze-dried (lyophilized) condition requiring only the addition of the sterile liquid carrier, for example water for injections, immediately prior to use. Extemporaneous injection solutions and suspensions may be prepared from sterile powders, granules and tablets of the kind previously described.
The dose will depend on a number of factors known to the skilled physician Including the severity of the conditions, the identity of the recipient; and also the efficacy and toxicity of the particular compound of general formula (I) which is being administered. Generally doses in the range 0.1-100 mg/kg body weight may be used, particularly 1-10 mg/kg. The frequency of administration will vary depending on the rate of metabolism or excretion of the administered compound, but may be repeated daily, optionally as two or more sub-doses. Unit doses of 20 to 500 mg, preferably 100 to 400 mg may be used.
The present invention further relates to a flavonoid compound of general formula (I) ##STR4## wherein R 1 , R 2 , R 3 , R 4 and R 5 are independently selected from H, OH and halo.
R 6 and R 7 are both H, or R 6 and R 7 together form a single bond; and
R is C 1-6 alkyl or alkenyl.
Embodiments of the invention will now be described by way of example only.
EXAMPLE 1
(Preparation of synthetic flavonoids)
1. Preparation of halogenated chrysin
2'-fluorochrysin and 2'-chlorochrysin were prepared by the Floc'h Lefeuvre synthesis (Tetrahedron Lett. 27, 5503-5504, 1985) by reaction of ortho-fluoro or chlorobenzoyl chlorides with the ylid obtained from 2,4,6-trihydroxyphenacylidene-triphenylphosphorane. Other compounds including 6,8 dibromo chrysin were prepared from chrysin using the classical Allan-Robinson synthetic route (J. Allan and R. Robinson (1924) J. Chem. Soc. p2192).
2. Preparation of 7-bromo flavone
Bromine was added to a solution of flavanone in carbon tetrachloride at 0° C. The ratio of bromine/flavanone was 1.3 in molar terms. The temperature of the solution was raised to 30° C. and kept there for 1 hour. The temperature of the solution was then raised to 65° C. and kept there for 45 minutes.
The reaction mixture was then extracted with an equal volume of a saturated solution of sodium metabisulphite and then dried with anhydrous sodium sulphate. The product was then recovered by evaporation of the solvent.
This gave a mixture of brominated flavones, in which the only active ingredient was identified by NMR analysis as 7-bromo flavone (as shown in FIG. 19).
EXAMPLE 2
(Experimental effect of flavonoids)
Animals
Male CF1 mice from our breeding stock weighing 28-35 g were used. The animals were placed in groups of 10-12 with free access to water and food, and maintained on a 12 h/12 h day-night cycle.
Drugs
Diazepam (DZ; Hoffman-La Roche) and the flavonoids were dissolved in DMSO 40%, NaOH 0.1N (7:3: v/v) at pH 8.2 Control animals were injected with the same vehicle (VEH). RO 15-1788 (Hoffmann-La Roche) was suspended in DMSO 10%, propyleneglycol 10% in distilled water.
Experimental Devices
(a) Elevated Plus Maze: consisted of 4 perpendicularly disposed wood arms (20×5 cm; two had 35 cm high wood walls, and two were open) linked by a central 10×10 cm square. The maze was suspended 50 cm from the room floor. Animals were placed on the central part of the maze facing a closed arm. This test has been widely validated to measure anxiety in rodents. The number of entries into and the time spent in the open and closed arms were counted during 5 min. A selective increase in the parameters corresponding to open arms reveals an anxiolytic effect. Total exploratory activity (number of entries in both arms) was also determined.
(b) Holeboard Test: consisted of a wood box (60×60×30 cm) with four 2 cm diameter holes equidistant in the floor. The number of head-dips and the time spent head-dipping were counted during 5 min. An increase in the number and the time spent head-dipping implies a greater exploratory activity. A decrease of both parameters reveals a sedative behavior.
(c) Locomotor Activity Test: we used an OPTO-VARIMEX apparatus consisting of a glass box (36×15×20 cm) and two lateral bars with 15 light beams (0.32 cm diameter, beam spacing 2.65 cm). The apparatus detects automatically all the mouse movements, and discriminates between total and ambulatory activity. The locomotor activity (number of movements across the beams) was counted during 5 min. An increase in the number of transitions through the beams reflects an augmented locomotor activity.
(d) Horizontal Wire Test: It consisted of an horizontally strung wire (1 mm diameter, 15 cm long), placed at 20 cm from the table. Mice were lifted by the tail, allowed to grasp the wire with their forepaws and released. The number of mice that did not grasp the wire with their forepaws or actively grasped the wire with at least one hindpaw within 3 sec was determined. After two trials, performed at 5 min. intervals, the test took place. A myorelaxant drug, like diazepam at high doses, will impair the ability of mice to grasp the wire. Generally, this state of muscle relaxation is commonly associated with sedation.
General Experimental Procedure
The general procedure for all the tests is as follows: mice were injected with vehicle or the drug solution 20 min before the beginning of the test and put into another home cage. Ro 15-1788, a specific BZD receptor antagonist was injected 10 min before the tested drug. All the injections were given intraperitoneally (i.p.). Control mice were tested in each session, in parallel with those animals receiving the test drug or diazepam. Testing was carried out `blind`. All data were submitted to analysis of variance (ANOVA). Post-hoc comparisons between individual treatments and controls were made using Dunnett's t-test.
Results
The results of experiments in devices (a) to (d) are summarised in the FIGS. 1-18.
FIG. 1 shows ambulatory locomotor activity counts during a 5 min test session in an OPTO-Varimex apparatus, 20 min after IP injection with DZ (0.3-3 mg/kg), or chrysin (CHRY, 0.6-10 mg/kg). Data are expressed as medians (interquartile range) of (n) number of animals. *p<0.05, **p<0.02, ***p<0.002 significantly different from controls (Mann Whitney test).
FIG. 2 shows mean (±S.E.M.) percentage of open arm entries (hatched bars) and percentage of time (sec) spent in the open arms (closed bars) in mice given a 5 min test in the elevated plus-maze, 20 min after i.p. injection with DZ (0.3 and 0.6 mg/kg), or CHRY (0.1-10 mg/kg). *p<0.01, significantly different from controls (two-tailed Dunnett's t-test after analysis of variance).
FIG. 3 shows mean (±S.E.M.) percentage of open arm entries (hatched bars) and percentage of time (sec) spent in the open arms (closed bars) in mice given a 5 min test in the elevated plus-maze, 20 min after i.p. injection with VEH, CHRY (1 mg/kg) or CHRY+RO 15-1788 (3 mg/kg) administered i.p. 10 min before chrysin. * p<0.01, significantly different from controls (two-tailed Dunnett's t-test after analysis of variance). No significant differences were found in the total arm entries (F (2,49)=3.18).
FIG. 4 shows mean (±S.E.M.) number of head-dips (closed bars) and time (sec) spent head-dipping (hatched bars) for mice given a 5 min test in the holeboard, 20 min after an i.p. injection with DZ (0.3-6 mg/kg) or CHRY (1-10 mg/kg). *p<0.05, **p<0.01, significantly different from controls (two-tailed Dunnett's t-test after analysis of variance).
FIG. 5 shows the performance of mice in the wire test 20 min after an i.p. injection with DZ (3 and 6 mg/kg) or CHRY (0.6-30 mg/kg). The test took place after two trials, executed after a 5 min interval.
FIG. 6 shows mean (±S.E.M.) of total entries, percentage of open arm entries (% Nr open) and percentage of time (sec) spent in the open arms (% T open) in mice given a 5 min test in the elevated plus-maze, and ambulatory activity in mice given a 5 min test in an OPTO-VARIMEX apparatus, 20 min after i.p. injection with vehicle and apigenin (1, 3, 10 mg/kg).
FIG. 7 shows mean (±S.E.M.) number of head-dips and time (sec) spent head-dipping and rearings for mice given a 5 min test in the holeboard, and performance to grasping the wire test, 20 min after an i.p. injection with vehicle and apigenin 3 and 10 mg/kg; and
FIG. 8 shows noradrenaline levels in locus coeruleus nucleus after a session of immobilization stress alone or with pretreatments as indicated in the figure (noradrenaline is expressed as per cent of control value) Apigenin blocked almost completely the noradrenaline decrease provoked by stress--first bar. (Chrysin was almost equipotent with diazepam).
FIG. 9 shows total entries, percentage of open arm entries (% number open) and percentage of time (sec) spent in the open arms (% time open) in mice given a 5 min test in the elevated plus-maze, and ambulatory activity in mice given a 5 min test in an OPTO-VARIMEX apparatus, 20 min after i.p. injection with vehicle and flavone (1,3 mg/kg).
FIGS. 10, 11, 12, 13 and 14 show mean (±S.E.M.) of total entries (hatched box), percentage of open arm entries (closed box) and percentage c: time (sec) spent in the open arms (cross hatched box) in mice given a 5 min. test in the elevated plus-maze, 20 min. after i.p. injection with vehicle and a mixture of brominated flavone (0.6, 1,3 mg/kg) in FIG. 10; 2' chlorinated chrysin (1,3 mg/kg) in FIG. 11 and 2' fluorinated chrysin (3 mg/kg) in FIG. 12; 6, 8 dibromo chrysin (1 mg/kg) in FIG. 13; 7-bromo flavone (0.5 mg/kg) in FIG. 14. *p<0.01, ** p<0.02, *** p<0.05, significantly different from the controls (student's t-test after analysis of variance).
FIGS. 15, 16, 17 and 18 show ambulatory locomoter activity counts during a 5 min. test session in an OPTO-Varimex apparatus, 20 min. after i.p. injection with a mixture of brominated flavones (0.6,1,3 mg/kg), FIG. 15; 2' chlorinated chrysin (1,3 mg/kg); FIG. 16; 2' fluorinated chrysin (3 mg/kg), FIG. 17; 6,8 dibromoflavone, FIG. 18. Data are expressed as medians (interquartile range) of (n) number of animals. No significant difference was observed in comparison to the controls (Mann Whitney test). No significant change was observed in ambulatory activity when 7-bromo flavone was compared against a control (data not shown).
In all the experiments, diazepam DZ (0.3-6 mg/kg) was used as reference drug. FIG. 1 shows the typical pharmacological profile of increasing locomotor activity by DZ. Similarly, there was a significant increase in locomotor activity with equipotent doses of chrysin (0.6-1 mg/kg). FIG. 2 shows the performance of mice following i.p. administration of vehicle, DZ or chrysin on the elevated plus maze. DZ (0.3 and 0.6 mg/kg) increased the percentage of entries in the open arms (p<0.01) and the percentage of the time spent on the open arms (p<0.01). Chrysin (1 mg/kg) produced also an increase in both parameters (p<0.01). No differences were observed in the total arm entries (Table 1). Thus both DZ and CHRY displayed an anxiolytic effect. The effect of chrysin (1 mg/kg) on the number of entries into and the time spent on the open arms was prevented by the prior administration of Ro 15-1788, a central BZD receptor antagonist (FIG. 3).
As shown in FIG. 4 in the holeboard DZ (0.3 mg/kg) increased the number of head-dips (p<0.05) and at 1 mg/kg increased the time spent head-dipping (p<0.01). As expected, DZ (6 mg/kg) induced a decrease in both the number of head-dips and in the time spent head-dipping (p<0.01) which indicates sedation.
Chrysin (3 mg/kg) produced a significant increase in the time spent head-dipping but did not elicit sedative effects at high doses (10 mg/kg).
FIG. 5 shows that at 6 mg/kg DZ significantly decreased the percentage of animals grasping the horizontal wire, indicating a muscle relaxant effect. On the other hand, chrysin (0.6-30 mg/kg) was ineffective in the same test and produced no muscle relaxant effect.
Thus, chrysin had anxiolytic effects in the elevated plus maze test but did not exhibit sedation or muscle relaxation.
FIGS. 6 and 7 show analogous results for apigenin (API.) Apigenin administered interperitonealy shows anxiolytic effects in the elevated plus maze test (FIG. 6); but did not induce any effect in the holeboard test (FIG. 7) or the horizontal wire test (FIG. 7) indicating no sedative or muscle relaxant activity.
FIG. 8 shows that both chrysin and apigenin dampened the noradrenaline decrease in the locus coeruleus provoked by immobilisation stress. In comparison to diazepam, apigenin showed the most potent effect.
The figure shows per cent change (related to controls) of locus coeruleus noradrenaline levels after stress and different treatment (as indicated in the figure). Rats were submitted to a 90-minute immobilization stress session in a plastic cylinder. The locus coeruleus was dissected out after killing by decapitation and noradrenaline assessed by HPLC with electrochemical detection. Doses were 1 mg/kg for each substance, injected i.p., 30 minutes before the stress session.
FIG. 9 shows the performance of mice following i.p. administration of vehicle, D2 or flavone on the elevated plus-maze. Flavone (1 mg/kg) increased the percentage of entries and time spent in the open arms (p<0.002) Mann-Whitney test.
FIG. 10 shows that at a concentration of 1 mg/kg a mixture of brominated flavones results in a significant increase in the number of entries into the open arms in comparison to the control. The corresponding ambulatory locomotion test (FIG. 14) shows no significant decrease in activity. Thus, the increased entries in the elevated plus-maze test show a reduction in anxiety without a significant decrease in activity (i.e. without a significant sedative effect).
A similar effect can be seen for 1 mg/kg administered 2' chlorinated chrysin (FIGS. 11 & 16), for 3 mg/kg administered 2' fluorinated chrysin (FIGS. 12 & 17), for 1 mg/kg administered 6,8 dibromo chrysin (FIGS. 13 & 18) and for 0.5 mg/kg administered 7-bromo flavone (FIG. 14).
EXAMPLE 3
(Competitive inhibition of H 3 -flunitrazepam to benzodiazepine receptor)
This experiment was carried out as a general screen for compounds exhibiting benzodiazepine-like activity, in order to identify compounds for testing for specific anxiolytic activity.
Binding of 3H-flunitrazepam (0.7 nM) to the benzodiazepine receptor was carried out in extensively washed cerebral cortical membranes.
H 3 -flunitrazepam has a Ki of 3 micromole to the benzodiazepine receptor.
IC 50 values were obtained using flavonoids at different concentrations (10 -10 to 10 -3 M).
Table II shows the results of the tests. Flavone, chrysin, apigenin and 6,8 dibromochrysin (IC 50 =0.7-3 um) show benzodiazepine ligand behaviour similar to that of 3 H-flunitrazepam. 7-bromo flavone and amentaflavone show a far higher affinity for the benzodiazepine receptor (IC 50 =0.05 um and 0.01 um respectively) than 3 H-flunitrazepam.
The other flavonoids show weak benzodiazepine ligand behaviour.
EXAMPLE 4
(Induced seizures in mice)
Benzodiazepines in general show an anxiolytic effect, a sedative effect and an anticonvulsant effect. In order to assess the present compounds for anticonvulsant activity the following experiment was carried out.
The method of Medina et al Biochem.Pharm. 40 p2227-2231, (1990) was followed (with the exception that injections were carried out intraperitoneally) and the mice observed for seizures.
Table III shows that apigenin has no anticonvulsant activity. This differs from the benzodiazepines and shows that the flavonoids have a more selective and specific mode of action, being limited to anxiolytic activity.
TABLE I______________________________________Total number of arm entries made by mice during 5 min testin the elevated plus-maze, 20 min after drug injection.DRUGS TOTAL(mg/kg) n ARM ENTRIES______________________________________VEH (53) 8.7 ± 0.6DZ 0.3 (21) 10.5 ± 0.8 0.6 (22) 12.4 ± 1.9CHRYSIN 1 (36) 9.9 ± 0.8 3 (21) 8.7 ± 1.110 (15) 10.2 ± 1.1______________________________________
Data are expressed as means ±S.E.M. of n=number of animals.
Analysis of variance F(5,160)=2.27, p<0.05
TABLE II______________________________________Structure - activity relationships of several flavonoids onthe .sup.3 H Flunitrazepam binding to bovine brain membranes. .sup.3 H FlunitrazepamFLAVONOID binding IC.sub.50 (uM)______________________________________Flavone 1Apigenin 3Isoquercetin 106,8 dibromochrysin 0.7Isoquercitrin 805 hydroxy 7 methoxyflavone 46Rutin 602' fluorochrysin 82' chlorochrysin 9chrysin 2flavanone 407-bromoflavone 0.05Amentoflavone 0.01Ginkgetin 5Isoginkgetin 4-5______________________________________
TABLE III______________________________________EFFECTS OF IP ADMINISTRATION OF APIGENIN ON PTZINDUCED SEIZURES IN MICE.Doses (mg/kg) Number of animals with clonic convulsions______________________________________PTZ 31/31Diazepam 3 + PTZ 0/6Apigenin 3 + PTZ 8/8Apigenin 20 + PTZ 3/3Apigenin 40 + PTZ 12/14Apigenin 80 + PTZ 11/11______________________________________
The convulsant doses of pentylenetetrazole are between 50-80 mg/kg in different experiments carried out in 6 independent days.
5,7-Dihydroxy-2'-fluoroflavone (2'-fluorochrysin). Light tan prisms, mp 273°-276° C. 1 H NMR δ (DMSO-d 6 ) 6.24 (1H,d, J=1.8 Hz, H-6), 6.47 (1H,d, J=1.8 Hz, H-8), 6.69 (1H,s,H-3), 7.44 (2H.m,H-3'/-6'), 7.67 (1H,ddd, J=6.1, J"=1.3 Hz.H-4' or -5'),7.98 (1H,ddd, J=J'=7.4, J"=1.2 Hz, H-5' or -4'), 12.67 (1H, s, C-5-OH). 13 C NMR δ (DMSO-d 6 ) 94.29(C-8), 99.33(C-6), 104.05 (C-4a), 109.84 (d, J=10.6 Hz. C-3), 117.10 (d, J=21.9 Hz, C-6'), 119.38 (d, J=10.6 Hz, C-1'), 125.42 (d, J=3.8 Hz. C-3'), 129.72 (C-5' or -4'), 134.05 (d, J=36 Hz, C-4' or -5'), 157.72 (C-8a), 158.71 (d, J=75 Hz, C-2'), 159.21 (C-2), 161.60(C-5), 164.82(C-7), 181.63(C4).
5,7-Dihydroxy-2'-chloroflavone(2'-chlorochrysin). Yellow granular powder, sublimes from 225° C., melts 273°-275° C. 1 H NMR δ (DMSO-d 6 ) 6.35 (1H, d, J=1.8 Hz, H-6), 6.50 (1H, d, J=1.8 Hz, H-8), 6.66(1H, s, H-3), 7.63 (1H, ddd, J='=7.5, J"=1.3 Hz. H-5' or -4'), 7.70 (1H, ddd, J='=7.6, J"=1.3 Hz, H-4' or 5'), 7.76 (1H, dd, J=7.8, J'=1.0 Hz H-6' or -3'), 7.78 (1H, dd, J=7.4, J'=1.2 Hz, H-3' or -6'), 12.67 (1H, s, C-5-OH). 13 C NMR δ (DMSO-d 6 ) 94.35 (C-8), 99.54 (C-6), 103.96 (C4a), 110.76 (C-3), 127.97 (C-5' or -4'), 130.69 (C-6' or 3'), 131.13 (C-1), 131.50 (C-3' or 6'), 131.81 (C-2'), 132.88 (C-4' or -5'), 158.02 (C-8a), 161.75 (C-5), 162.86 (C-7), 165.26 (C-2), 181.58 (C4).
6,8-Dibromo-5, 7-dihydroxyflavone (6,8-dibromochrysin). Prepared by bromination of chrysin at room temperature with excess bromine in acetic acid. Very fine, light yellow needles, subliming from 265° C. to give prisms, mp (309) 320° C., 1H NMR δ (DMSO-d6) 7.17 (s, H-3), 7.59 (dd, J=J'=6.5 Hz. H-3'/5'), 7.62 (dd, J=J'=6.5 Hz, H-4'), 8.12 (d, J=6.4 Hz, H-2'/6'), 13.71 (s, C-5-OH). 13 C NMR δ (DMSO-d 6 ) 88.37 (C-8), 94.47 (C-6), 105.03 (C-4a), 126.0 (C-3), 126.37 (C-2'/6'), 129.14 (C-3'/5'), 130.13 (C-1'), 132.35 (C-4'), 152.18 (C-7), 156.97 (C-8a or -5), 157.34 (C-5 or 8a), 163.41 (C-2). 181.44 (C-4).
Tectochrysin (5-hydroxy-7-methoxyflavone). Prepared from chrysin by warming with one equivalent of dimethyl sulphate in DMF with finely ground K 2 CO 3 . Fine, light yellow needles, mp 175°-180° C. (lit. 163° C.). 1 H NMR δ (DMSO-d 6 ) 3.87 (s,OCH 3 ), 6.39 (d, J=1.7 Hz, H-6), 6.80 (d, J=1.7 Hz, H-8). 7.02 (s,H-3), 7.58 (dd, J=J'=7.8 Hz, H-3'/5'), 7.60 (tt, J≈7.8 Hz, H-4'), 8.09 (d,J=7.8 Hz, H-2'/6'), 12.80 (s, C-5-OH).
5,7-Dimethoxyflavone (chrysin 5,7-di-O-methyl ether). Prepared similarly to the previous compound, but with excess dimethyl sulphate. Light tan powder, mp 147°-149° C. 1 H NMR δ (CDCl 3 ) 3.91 (s,OCH 3 ), 3.96 (s,OCH 3 ), 6.37 (d, J=2.0 Hz, H-6), 6.57 (d, J=2.2 Hz, H-8), 6.68 (s, H-3), 7.50 (dd, H-3'/5'), 7.51 (tt, H-4'), 7.87 (d, J=5.3 Hz?, H-2'/6').
2'-Chloro-5-hydroxy-7-methoxyflavone (2'-chlorotectochrysin). Prepared from 2'-chlorochrysin by warming with one equivalent of dimethyl sulphate in DMF with finely ground K 2 CO 3 . Light yellow needles, sublimes from 160° C., melts 183°-185° C. 1 H NMR δ (DMSO-d 6 ). 3.88 (s,OCH 3 ), 6.47 (br s, H-6), 6,66 (s, H-3), 6.72 (br s, H-8), 7.6 (m, H-3'/4'/5'), 7.82 (br d, J≈6.9 Hz, H-6'), 12.64 (s, C-5-OH).
2'-Chloro-6,8-dibromo-5,7-dihydroxyflavone (2'-chloro-6,8-dibromochrysin). Prepared from 2'-chlorochrysin by bromination with excess bromine in acetic acid. Very fine, pale yellow needles, sublimes from 250° C., melts 285°-290° C. 1 H NMR δ (DMSO-d 6 ) 6.83 (s, H-3), 7.6 (3H, m, H-3'/4'/5'), 7.84 (d, J=6.2 Hz, H-6'), 13.59 (s, C-5-OH). 13 C NMR δ (DMSO-d 6 ) 88.66 (C-8), 94.97 (C-6) 105.20 (C-4a), 111.02 (C-3), 128.02 (C-5'), 130.50 (C-6'), 130.90 (C-1'), 131.72 (C-3'), 131.91 (C-4'), 133.24 (C-2'), 152.99 (C-7), 157.26 (C-8a or -5), 157.88 (C-5 or -8a), 163.30 (C-2), 181.40 (C-4). | Certain flavonoids, notably derivatives of flavone, chrysin and apigenin, together with dimers thereof such as amentoflavone, have been found to possess anxiolytic properties (i.e., anxiety reducing properties) without exhibiting a sedative effect. Novel compounds and pharmaceutical formulations are also described. | 2 |
FIELD OF THE INVENTION
The present invention relates generally to commercial food chilling equipment and, more particularly, to chillers having features for minimizing the potential for user error and confusion during the set-up and monitoring of a chilling operation.
BACKGROUND OF THE INVENTION
Commercial food product chillers, commonly referred to as blast chillers, are typically used to chill hot food products to a safe temperature for storage. For example, a hot food product at 145° F. to 160° F. or more may be taken just out of the oven, placed in the chiller, and rapidly cooled to a low temperature of 40° F. or less. Such rapid chilling of the food product is desirable for a variety of reasons, including food safety.
Known food product chillers generally operate in one of two modes, namely a chill by temperature mode or a chill by time mode. In the chill by temperature mode a temperature probe is placed in the food product and the desired chilled temperature of the food product can be entered into the machine by a user. The chilling operation then runs until the temperature probe indicates that the food product has reached the desired chilled temperature. In the chill by time mode, a user simply enters a time period for chilling the food product and the chilling operation then runs for the entered time period. In either type of chilling operation a user may also set the type of chill (hard or soft), and/or a desired air temperature within the chilling compartment. Some chillers are also configured to operate in a freeze mode for freezing food products. As used herein the term “chiller” broadly encompasses both units which include a freeze mode and units which do not include a freeze mode.
One opportunity for user error with known chillers occurs during the initialization of a chill by temperature operation when the user must select one of several temperature probes to monitor the cooling cycle of a hot food product. When this step is performed properly, the user will insert a given temperature probe into a hot food product and identify the inserted probe for use in the chilling operation through a user input device. For this purpose the probes are typically numbered. The identified temperature probe will then monitor the temperature of the food product as it is cooled. Occasionally, however, the user will accidentally identify a different temperature probe than the one placed into the hot food product causing the cooling cycle of the food product to run improperly. When this error occurs it may also be necessary to discard the food product. Consequently, it would be desirable to provide a method for automatically identifying for use a temperature probe that has been placed into a hot food product, thereby eliminating the potential for user error.
Another opportunity for user confusion occurs during the loading and unloading of food products through a chiller door. Because opening of the chiller door can cause rapid temperature increases in the cooling compartment, users who monitor the cooling compartment temperature through a temperature display may become concerned that the chilling operation has been interrupted. When this confusion occurs users will occasionally discard food products as waste thinking them unsafe. A similar problem can occur in other types of cooling apparatus such as refrigerators having temperature displays. Accordingly, it would be desirable to provide a method for filtering the temperature that is displayed to the user in a manner such that the responsiveness of the display to rapid temperature changes in the cooling compartment is reduced when the door is opened, thereby eliminating the potential for user confusion.
SUMMARY OF THE INVENTION
In a first aspect of the present invention, a chiller apparatus is provided including a chilling compartment, a chilling system for chilling the chilling compartment, and a plurality of temperature probes for monitoring the temperatures of food products during chilling operations. A controller is coupled to the temperature probes for receiving signals therefrom and is capable of determining whether to identify a given temperature probe for use in a chilling operation based, at least in part, on a signal received from the given temperature probe.
In a second aspect of the invention, in a chiller including a chilling compartment having a plurality of temperature probes associated therewith, a method for automatically determining whether a given temperature probe has been selected for use in a chilling operation is provided. The method involves comparing a temperature of the given temperature probe to a threshold temperature; and determining whether the given temperature probe has been selected for use in the chilling operation based at least in part upon the comparison. In one embodiment the determination is made in order to automatically identify the given probe for use in the chilling operation if a user selected the given probe by placing it in a hot food product. In another embodiment, the given probe may be examined based upon user identification of the given probe via a user input device, wherein the determination is made in order to verify that the user identification of the given probe was correct.
In a third aspect of the invention, a method for displaying an air temperature of a cooling compartment involves altering the responsiveness of the temperature that is displayed to temperature changes according to the status of the cooling compartment door as being open or closed. When the door is closed the temperature that is displayed is most responsive to temperature changes in the cooling compartment. When the door is open the responsiveness of the temperature display to temperature changes is decreased in order to reduce the likelihood of user confusion.
In the fourth aspect of the present invention, a cooling apparatus is provided including a cooling compartment, a cooling system for cooling the cooling compartment, and a door which can be opened to load or unload food products from the cooling compartment. An air temperature sensor is used to obtain an air temperature of the cooling compartment and a display device is used to display the air temperature to the user. A controller is coupled to the air temperature sensor and the display device for displaying a temperature based, at least in part, on a signal received from the air temperature sensor. The controller is also coupled to a door state sensor and is operable at least once during an open state of the door to reduce the responsiveness of the display temperature to temperature changes in the cooling compartment.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic depiction of one embodiment of a chiller;
FIG. 2 is a wiring schematic of the chiller of FIG. 1;
FIG. 3 is a flowchart depicting one embodiment of an automatic probe detection algorithm; and
FIG. 4 is a flowchart depicting one embodiment of a temperature filtering algorithm.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Referring to drawing FIG. 1, a schematic depiction of a chiller 10 according to one embodiment of the present invention is shown. The chiller 10 includes a chilling compartment 12 which may include multiple racks or shelves (not shown) for receiving food products to be chilled, the compartment typically defined by an insulated housing having an associated door 13 movable between open and closed positions. A plurality of temperature probes 14 are positionable in the chilling compartment 12 for insertion into food products placed in the chilling compartment 12 . The probes 14 may be connected to a common wiring harness 16 which extends to a controller 18 . The probes 14 output temperature indicative signals to the controller 18 . An air temperature sensor 20 is also provided for sensing the temperature of air in the chilling compartment 12 and producing a temperature indicative signal which is delivered to the controller 18 . A chilling system 22 , operated by the controller 18 , generates chilled air which is delivered to the chilling compartment 12 during chilling operations. The chilled air may be circulated through the chilling compartment and back to the chilling system using one or more fans or blowers (see FIG. 2 ).
The controller 18 is also connected to a display device 24 , such as an LCD screen or VF display, for effecting display of information to a user. A user input device 26 is provided for allowing a user to input information to the controller 18 . In one embodiment the user input device 26 may be a series of input keys or buttons along the sides of the display device 24 which allow a user to initiate actions or enter information according to information displayed on a portion of the display device 24 alongside the keys. Other user input devices could be used. For example, the user input device could be combined with the display device in the form of a touch screen display, or an alphanumeric data entry key array could be provided.
The chiller includes a label printing mechanism 28 having an associated supply of adhesive label stock. The controller 18 is connected for effecting printing of labels by the printing mechanism 28 . A ticket printing mechanism 30 having an associated supply of non-label print stock is also provided, with the controller 18 connected to effect printing of tickets by the printing mechanism 30 . In one embodiment, the printing mechanisms may be formed by thermal print heads.
Referring now to FIG. 2, a schematic diagram of chiller wiring is shown. The controller 18 may include an RS- 232 communications interface 32 , a programming interface 34 , and an expansion interface 36 . The programming interface 34 may be used to reprogram the controller 18 . In the illustrated embodiment the controller 18 is connected directly to certain components and indirectly, through input/output board 38 , to others. The controller is directly connected to each of the temperature probes 14 , the air temperature sensor 20 , the user input device 26 , the display device 24 , and the printing mechanisms 28 and 30 . The controller is also directly connected to an evaporator coil temperature sensor 40 which may be used in defrost operations of the coil.
The controller 18 is connected through input/output board 38 to fans 42 , 44 and 46 for controlling the flow of chilling air through the chilling compartment. The controller 18 is connected through input/output board 38 to the coil portion 48 of the coil heater relay CH which effects contactor portion 50 . The controller 18 is also connected through the input/output board 38 to solenoid 52 which is connected in line with the chilling system 22 to control the flow of the refrigerant fluid. Because operation of the compressor motor 54 and fan 56 of the chilling system 22 is responsive to high and low pressure switches 58 and 60 , the chilling system can be controlled via control of the solenoid 52 . Left and right heater elements 62 and 64 are provided for defrosting.
A front door switch 66 and fan door switch 68 are also connected through input/output board 38 to controller 18 and properly positioned for providing signals indicative of the open/closed state of each of the chilling compartment door 13 and fan compartment door (not shown). Contact, magnetic, optical or other suitable switches could be used. The controller 18 can also effect operation of an alarm 70 , such as a beeper, light or other annunciator, through the input/output board 38 . Power supplies 72 and 74 are also shown.
Referring now to FIG. 3, one embodiment of an automatic probe detection method is shown and is identified as an Activate Probes routine. The operations of the method may be performed by the controller 18 which includes associated memory (EEPROM, RAM, ROM and/or other memory) for storing operating code and other information. The data that are used to carry out the operations of the method are supplied to the controller 18 by the plurality of temperature probes 14 , the air temperature sensor 20 , and the user input device 26 . The method may be started when a user, via the user input device 26 , requests a chill by temperature operation after at least one of a plurality of temperature probes 14 is inserted into a hot food product. Of course in other embodiments the method could be performed continuously in which case the temperature probe 14 could be inserted into a food product at any time in relation to the start of the method.
The Activate Probes routine is initiated at step 80 . A number of variables are then initialized in step 82 . The variables include: a count variable (n) that identifies which temperature probe is currently under consideration for use; a status variable (ACTIVE) that indicates whether one or more probes are active—initialized to false; and a temperature variable (delta) is set to a given value. In the embodiment pictured in FIG. 3, the temperature variable (delta) is a stored parameter that cannot be altered by the user. In other embodiments, however, the temperature variable (delta) could be variable by the user by means of the user input device 26 or could be varied automatically.
No matter how delta is set, in the illustrated embodiment it is then added to some measured temperature in step 82 to calculate a threshold temperature. The threshold temperature may be calculated by adding the temperature variable (delta) to a measured air temperature in the chilling compartment as determined by the air temperature sensor 20 . In other embodiments however, a unique threshold temperature could be calculated for each temperature probe by adding the temperature variable (delta) to a prior measured temperature of each temperature probe that had been stored in memory by the controller 18 . In some applications the threshold temperature may simply be a predetermined constant stored in memory.
Starting with the first temperature probe and proceeding sequentially through each of the temperature probes, a series of operations is used to determine whether to identify each probe for use in a chilling operation. When the operations are completed on any given probe the counter variable (n) is increased and the next probe sequentially is considered. In the embodiment shown in FIG. 3, each temperature probe will be considered in turn only once. Therefore, at least one temperature probe 14 should be inserted into a hot food product before the method is started in step 80 in order for a temperature probe to be identified for use. In other embodiments, however, the steps could repeat for a certain time period to give a user a chance to insert a probe.
In step 84 , the disabled status of the temperature probe currently under consideration is tested. A probe may be disabled because it is not functioning properly. If it is determined that the probe currently under consideration is disabled, then the counter variable is increased and the next temperature probe is considered. If it is determined that the probe currently under consideration is not disabled, then the idle status of the probe is tested in step 86 .
A temperature probe that is currently in use in a chilling operation is not idle and therefore not available for identification for use in another chilling operation. If the status of the probe is determined not to be idle then the counter variable (n) is increased at step 92 and the next temperature probe is considered. If the status of the probe currently under consideration is determined to be idle, then the temperature of the probe is compared, in step 88 , to the threshold temperature.
A primary assumption of the embodiment shown in FIG. 3 is that the temperature of a probe that is not in a food product will be close to the air temperature of the chilling compartment since the probes are stored in the chilling compartment when not in use. Therefore, if the temperature of a probe is greater than the air temperature of the chilling compartment plus the temperature variable (delta), that is greater than some threshold temperature, then a conclusion is made that the probe has been inserted into a hot food product. Consequently, in step 88 the temperature of the probe currently under consideration is compared to the threshold temperature to determine whether to identify the probe for use in a chilling operation. If the temperature of the probe does not exceed the threshold temperature then the counter variable (n) is increased in step 92 and the next temperature probe is considered. If the temperature of the probe currently under consideration does exceed the threshold temperature then the probe under consideration is set to active and the status variable (ACTIVE) is changed from false to true in step 90 . A probe status table may be maintained in memory for identifying active probes, and the probe may be set to active by flipping a bit in the table. Once set to active, the probe has been identified for use in a subsequent chilling operation. Even after a probe is identified for use in a chilling operation the counter variable (n) is increased in step 92 and the next temperature probe is considered in case the user has elected to use more than one probe.
In the embodiment shown in FIG. 3 only three temperature probes are envisioned for use although clearly more could be used. In step 94 a determination is made as to whether all of the temperature probes have been considered by comparing the counter variable (n) to the specified number of probes ( 3 in this case). If the counter variable is less than the specified number of probes then the automatic probe detection algorithm is not completed and step 84 will be repeated. If the counter variable is not less than the specified number of probes then all probes have been checked and the state of the status variable (ACTIVE) is returned. If ACTIVE has been set to true, the controller 18 examines the probe status table to determine which probe or probes to use in the chilling operation, and may also display via the display device 24 which probes will be used. If ACTIVE is still false, then no probe has been identified and the controller 18 may query the user via the display device 24 to manually insert and identify a probe.
Where a user does manually identify which probe to use in a chilling operation, the controller 18 may verify whether the user's identification is correct. For example, if a user manually identifies a given probe for use the controller 18 may monitor that probe for a period of time to determine if that probe has in fact been placed in a hot food product. Such monitoring would similarly be achieved by evaluating whether the temperature of the given probe rises above a threshold temperature. If a determination is made that the manually identified probe was in fact placed in a hot food product the chilling operation may proceed as normal. On the other hand, if temperature of the manually identified probe does not rise above the threshold temperature the controller determines that the user accidentally identified the incorrect probe and may prompt the user via the display device or an alarm to verify and/or correct the probe identification.
Referring now to FIG. 4, one embodiment of a temperature filtering method is shown. The steps of the method may be performed by the controller 18 which includes associated memory (EEPROM, RAM, ROM and/or other memory) for storing operation code and other information. The data that are used to carry out the operations of the algorithm are supplied to the controller 18 by the air temperature sensor 20 and the front door switch 66 . Although at least four distinct filtering methods are contemplated, only one such method is shown in FIG. 4 . In each method, including the one shown in FIG. 4, adjustments to the filtering operation are initiated when the chilling compartment door 13 is opened as determined by the front door switch 66 .
The illustrated embodiment of the present invention that is shown in FIG. 4 utilizes a continuously repeating algorithm that begins in step 110 with the initialization of variables. These variables include an adjustment variable (Adjust) which is set to zero. After initialization of the variables in step 110 , in step 112 a determination is made as to whether it is time to consider adjusting the filtering procedure. This determination can be made, for example, by measuring absolute time, i.e., every 5 seconds, or by counting the number of complete passes through the algorithm, i.e., every 10 passes.
If, after the determination in step 112 , it is not time to consider adjusting the filtering procedure, then a Sum value is adjusted in step 118 by subtracting the value of the average temperature (AVG) that was calculated in step 120 on the previous pass through the filtering algorithm, adding the current measured temperature (New), and adding the current value of the adjustment variable (Adjust). Using this calculated Sum value a new average is then calculated in step 120 by dividing the Sum value by 2 n , wherein 2 n represents the size of the averaging window. After the new average temperature is calculated in step 120 , the calculated value is displayed to the user in step 122 by means of the display device 24 , which is coupled to the controller 18 , and the algorithm is then repeated.
If, after the determination in step 112 , it is time to consider adjusting the filtering procedure, then the open status of the chilling compartment door 13 is tested in step 114 by means of the front door switch 66 . If the door is open then the current value of variable n is compared in step 128 to a maximum variable value. If the current value of the variable n is less than the maximum variable value then the value of adjustment variable (Adjust) is calculated in step 130 by multiplying the average temperature (AVG) that was calculated in step 120 on the previous pass through the filtering algorithm by 2 n . The value of the variable n is then increased in step 132 before calculating a new Sum and average in steps 118 and 120 respectively. After the new average temperature is calculated in step 120 , the calculated value is displayed to the user in step 122 by means of the display device 24 and the filtering method is then repeated. By increasing (n) at step 132 and increasing Sum by a non-zero Adjust value which is a factor of the previous average, the size of the averaging window is doubled making the displayed temperature less responsive to changes in temperature within the chilling compartment. In this method it is possible for the size of the averaging window to be increased more than once. It is also possible that the averaging window will not be increased at all if the door 13 is only open for a few seconds.
Referring again to step 128 , if the value of the variable n is not less than the maximum variable value, then steps 118 , 120 and 122 are performed with no change to n and with Adjust=0.
Referring again to step 114 , if the status of the chilling compartment door 13 is determined not to be open, then the value of the variable (n) is compared in step 116 to a minimum variable value. If the value of the variable (n) is greater than the minimum variable value, then the value of the variable (n) is decreased in step 124 and the adjustment variable (Adjust) is calculated in step 126 by multiplying the average temperature that was calculated in step 120 on the previous pass through the filtering algorithm by 2 n , and taking the negative of that product. A new sum and average are then calculated in steps 118 and 120 respectively. After an average temperature is calculated in step 120 , the calculated value is displayed to the user in step 122 by means of the display device 24 and the filtering algorithm is then repeated. By decreasing (n) and then reducing Sum by the negative Adjust value, the size of the averaging window is halved. Referring again to step 116 , if the value of the variable n is not greater than the minimum variable value then steps 118 , 120 and 122 are performed directly with no change to n and with Adjust=0.
During initialization of the algorithm shown in FIG. 4 there will be no previous sum or previous average temperature until a sufficient number of temperature measurements are taken and stored in the memory of the controller 18 . Therefore, in the embodiment shown in FIG. 4, a startup operation may be performed when the unit is turned on, before entering the continuous filtering algorithm, during which a specified number of temperature samples are taken. Using the temperature samples from the startup operation an initial Sum and average temperature (AVG) are calculated for use during the first pass through the filtering algorithm. In other embodiments the startup operation could continue for a specified amount of time rather than a specified number of passes or temperature measurements.
Of course, the illustrated method of reducing the responsiveness of the displayed temperature to changes in temperature within the chilling compartment when the door is opened is merely one of many possible techniques. For example, a list of previously measured temperatures may be maintained in memory and each time the temperature is displayed it may be an average of a certain number (X) of the last measured temperatures as retrieved from the list. When the door is determined to be opened X may be increased in order to increase the size of the averaging window. In another alternative, when the door is determined to be open the frequency with which the air temperature of the chilling compartment is measured may be reduced. In yet another alternative, when the door is determined to be open the frequency with which the average temperature is calculated and displayed may be reduced.
Further, although not illustrated in the flow chart of FIG. 4, it may also be desirable to incorporate a temperature display filtering phase out after the door has been open for a certain time period. For example, if the door is open for more than a certain time, the temperature display filtering routine may automatically begin to make adjustments, such as decreasing the size of the averaging window, to make the displayed temperature less responsive to changes in temperature within the chilling compartment so that the temperature display will alert the user to a door open problem. The certain time period may, by way of example and not by way of limitation, may be 30, 60, 90 or 120 seconds.
Although the invention has been described and illustrated in detail it is to be clearly understood that the same is intended by way of illustration and example only and is not intended to be taken by way of limitation. For example, while the temperature filtering method has been shown and described relative to a chiller having a chilling compartment, it is recognized that a similar filtering method could be used on other types of cooling equipment having temperature displays, such as refrigeration units. As used herein the term “cooling apparatus” is intended to encompass both chillers and refrigeration units, and the term “cooling compartment” is intended to encompass both the chilling compartment of a chiller and the refrigeration compartment of a refrigerator.
Other changes and modifications could be made without departing from the invention. Accordingly, the spirit and scope of the invention are to be limited only by the terms of the appended claims. | In a chiller, an apparatus and method for automatically identifying a temperature probe for use in a chilling operation is provided in order to reduce user error. In the place of manual selection by a user, automatic selection of the appropriate temperature probe is accomplished by comparing the temperature of the given temperature probe to a threshold temperature. An additional apparatus and method for filtering a displayed compartment temperature is provided to reduce user confusion. The responsiveness of the displayed temperature to temperature changes in the compartment is reduced when the compartment door is opened. | 5 |
The present invention relates to an apparatus for manufacturing multilayer articles made of textile material, particularly but not exclusively the perimetric bands of mattresses provided with ventilation slots. In the continuation of the description, the definition of “textile material” is understood to reference materials which can be subjected to quilting processes, such as fabrics, non-woven fabrics, felt, expanded synthetic materials, such as polyurethane foams and the like.
BACKGROUND OF THE INVENTION
As is known, mattresses comprise an upper multilayer sheet and a lower sheet, the edges of which are mutually connected by a perimetric band, forming the case of the mattress, in which an insert is accommodated which is constituted by a cage of cylindrical spiral springs or by a panel of expanded plastic material which has elastic properties.
To allow internal ventilation of the mattress, the perimetric band of the case is provided with slots.
European Patent Application No. 07114821.7 filed Aug. 23, 2007 in the name of this same Applicant discloses a band for the perimetric closure of mattresses in which a strip of breathable textile material is arranged so as to cover the ventilation slots.
SUMMARY OF THE INVENTION
The aim of the present invention is to provide an apparatus which allows to apply, by means of stitched seams, a strip onto a band which is aligned with it.
Within this aim, an object of the present invention is to provide an apparatus which allows to provide ventilation slots within the band and in alignment with said band and to apply, by means of stitched seams, a breathable textile strip to cover the ventilation slots.
Another object of the present invention is to provide an apparatus which allows to prepare continuously or intermittently a multilayer band provided with ventilation slots and to associate continuously or intermittently with said band, by means of stitched seams, a strip for covering the slots.
This aim and these and other objects which will become better apparent hereinafter are achieved with an apparatus for manufacturing multilayer articles, characterized in that it comprises first means for feeding a band made of textile material, a punching device which is arranged downstream of said first feeder means and is adapted to form slots in said band, second means for feeding a strip of textile material which are arranged downstream of said punching device and are adapted to arrange said strip so as to cover said slots, a sewing apparatus which is arranged downstream of said second means and is adapted to fix, by means of stitched seams, said strip onto said band so as to cover said slots, so as to provide a multilayer article, and a traction assembly which is arranged downstream of said sewing apparatus in order to actuate the advancement of said article through said sewing apparatus toward a collection unit.
BRIEF DESCRIPTION OF THE DRAWINGS
Further characteristics and advantages of the invention will become better apparent from the following detailed description of a preferred but not exclusive embodiment thereof, illustrated by way of non-limiting example in the accompanying drawings, wherein:
FIG. 1 is a perspective view of an apparatus according to the invention;
FIG. 2 is a perspective view of the apparatus, taken from the opposite side with respect to FIG. 1 ;
FIG. 3 is a side view of the apparatus;
FIG. 4 is a plan view of the apparatus of FIGS. 1 and 2 ;
FIG. 5 is a sectional view, taken along the plane A-A of FIG. 3 ;
FIG. 6 is a sectional view, taken along the plane B-B of FIG. 4 ;
FIG. 7 is a sectional view, taken along the plane D-D of FIG. 4 ;
FIG. 8 is a sectional view, taken along the plane E-E of FIG. 4 ;
FIG. 9 is a perspective view of the traction assembly;
FIG. 10 is a front view of the assembly of FIG. 9 ;
FIG. 11 is a side view of the assembly of FIG. 9 ;
FIG. 12 is a sectional view, taken along the plane C-C of FIG. 10 ;
FIG. 13 is a perspective view of the region where the strip is applied to the band.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
With reference to FIGS. 1 , 2 , 3 and 4 , the apparatus is composed of a main frame, generally designated by the reference numeral 1 , upstream and downstream of which, with respect to the advancements direction F of the band and of the strip which co-operate to form the final article, respective brackets 2 , 3 protrude.
The bracket 2 supports three reels 4 , 5 , 6 , which are mounted so that they can rotate on respective shafts 7 , 8 , 9 and protrude in a cantilever fashion from the bracket 2 . Two ribbon-like fabrics 10 , 11 are wound around the reels 4 , 6 , whereas an intermediate insert 12 is wound onto the intermediate reel 5 and is constituted for example by a tape made of flexible expanded plastic material ( FIG. 3 ). The two fabrics 10 , 11 and the insert 12 are unwound in the feeding direction F from the respective reels 4 - 6 and are conveyed between a pair of parallel rollers 13 , 14 , which are mounted so that they can rotate on a secondary frame 15 which is fixed to the main frame 1 . Conveniently, tensioning rollers 16 act on the fabrics 10 , 11 in order to maintain the correct tension.
The fabrics 10 , 11 and the insert 12 have the same width, so that at the output from the rollers 13 , 14 they form a single three-layer tape which is referenced hereinafter, for the sake of convenience in description, as the band 17 . The band 17 is then guided through a punching device, generally designated by the reference numeral 18 and shown in greater detail in FIGS. 5 and 6 .
The punching device 18 is composed of a pair of mutually parallel and superimposed rollers 19 , 20 , which are supported so that they can rotate in two side walls 21 , 22 which rise from the main frame 1 . The rollers 19 , 20 are provided with pivots which pass through the side wall 22 and on which a gear is keyed which is composed of a pair of sprockets 23 , 24 which have the same diameter and mesh together.
A pulley 25 is also keyed onto the same pivot onto which the lower sprocket 24 is keyed, and a transmission belt 26 is wound onto said pulley and, by means of an additional belt 27 , receives motion from a motor 29 which is coupled by means of a flange to the sewing machine 36 described below.
The belt 27 is closed in a loop on a pulley 28 , which is keyed to the output shaft of the motor 29 , and on a pulley 28 a , which is keyed to an auxiliary shaft on which the pulley 27 a for guiding the belt 26 is keyed.
By virtue of the gear system 23 , 24 , the rollers 19 , 20 contrarotate with respect to each other so that the direction of rotation is F in the point of tangency.
The rollers 19 , 20 have such a diameter as to define, in their point of tangency, a slit which is adapted to keep the strips 10 , 11 in contact against the upper and lower faces of the intermediate insert 12 , optionally applying adequate compression to the latter.
Two punches 30 , 31 are arranged diametrically within the rollers 19 , 20 , in a central position thereof, and have respective ends which mutually cooperate so as to provide a sort of punching blade which is adapted to form slots 32 in the band 17 which is guided between the rollers. For this purpose, one end of a punch forms, as shown more clearly in FIG. 6 , an annular blade which, along the arc of the rotation in which the punches are mutually opposite, engages a complementary blade which is formed at the end of the other punch, cutting through the band at each turn of the rollers and forming slots 32 which are equidistant along a central line of the band 17 .
Downstream of the punching device 18 there are two additional rollers 33 , 34 , which can rotate within a secondary supporting frame 35 which is fixed to the main frame 1 . The rollers 33 , 34 are designed to divert the band 16 toward a sewing apparatus 36 , upstream of which there is an interposed additional pair of rollers 37 , 38 which are supported so that they can rotate within a secondary frame 42 and are designed to associate with the band 17 a strip 39 made of breathable textile material.
The strip 39 is taken from a reel 40 , which can rotate on a shaft 41 which is supported at the ends of two angled arms which extend upward from the sides of the secondary frame 42 ( FIG. 3 ) for supporting the rollers 37 , 38 .
The sewing machine 36 ( FIGS. 7 , 8 ) has a traditional structure and comprises a camshaft 43 , which is supported so that it can rotate within the side walls of a portal-shaped framework 43 a , which is fixed to the frame 1 downstream of the sewing machine. The camshaft 43 is connected by a belt 44 to the same motor 29 that drives the belt 27 , which by means of the other belt 26 actuates the punching device 18 .
The camshaft 43 , by means of a pair of linkages 45 , imparts a reciprocating motion to the bar 46 which carries the sewing needles 47 which are functionally associated with the respective crochets 48 .
As shown more clearly in FIG. 13 , in the described example there is a series of needles 47 , of which the two central ones 47 a fix the lateral edges of the strip 39 onto the central region of the band 17 , so as to cover the slots 32 , while the remaining needles continue to join together the fabrics 10 , 11 and the insert 12 along the lateral regions with respect to the band 32 .
The described apparatus further comprises a traction assembly, which is generally designated by the reference numeral 49 and is arranged downstream of the sewing machine 36 ( FIGS. 9-12 ).
The traction assembly 49 is designed to grip the band 17 that abandons the sewing apparatus or machine 36 already provided with the strip 39 and to impart an intermittent advancement movement to the band 17 .
The assembly 49 comprises a box-like body which has two side walls 50 , 51 , which are mutually connected by a cross-member 52 for fixing below the plane of the frame 1 . The side walls 50 , 51 support a shaft 53 whose opposite ends protrude outside the side walls. A pulley 54 is keyed onto one end and, by means of a belt 55 , receives motion from the motor 29 ; an eccentric element 56 is keyed onto the other end.
A bracket 57 is externally rigidly coupled to the side wall 50 and together with said side wall supports a shaft 58 which is parallel to the shaft 53 .
A pulley 59 and a bush 60 provided with a radial arm 61 which extends upward ( FIG. 12 ) are keyed onto the shaft 58 . The arm 61 is connected to the eccentric element 56 by a tension element 62 of adjustable length. A driving belt 63 is wound around the pulley 59 and is closed in a loop around an additional pulley 64 , which is coupled rotatably, together with a second pulley 65 having a smaller diameter, to a pivot 66 which is supported rotatably on parts of the box-like body which are not shown in the drawing but can be deduced easily.
By means of a narrow belt 67 , the pulley 65 transmits motion to a pulley 68 which is keyed onto a pivot 69 which extends axially from one end of a roller 70 which is supported rotatably within the body of the assembly 49 and has a knurled external surface.
A first gear 71 is fixed rotationally to the pivot 70 , to the side of the pulley 68 , and a second gear 72 meshes therewith and is associated with a roller 73 which is parallel to the roller 70 . In FIG. 9 , the gears 71 , 72 are shown mutually disengaged for the sake of clarity of the drawing.
To allow the intermittent advancement motion of the band 16 only in the direction F, a one-way joint or freewheel is incorporated into the bush 60 and allows to use the oscillation of the arm 61 only in the direction F.
It should be noted that the traction assembly 49 is synchronized with the sewing machine 36 so that the advancement movements of the band 17 produced by the rollers 70 , 73 occur when the bar 46 of the needles is raised and therefore the needles 47 are disengaged from the band 17 .
The described apparatus is completed by a sliding surface 74 which conveys the band 17 toward a takeup reel 75 , which is mounted on the bracket 3 and actuated by a motor 76 .
Although the operation of the apparatus can be deduced already from the above description, it occurs as follows.
The fabrics 10 , 11 and 12 , once they have been joined by the rollers 13 , 14 , form a band 17 which is punched inside the device 18 .
After passing beyond the device 18 , the band 17 passes through the sewing machine 36 , where the strip 39 is joined so as to cover the slots 32 .
Conveniently, as shown in FIG. 13 , upstream of the needles 47 there is a tucking plate 77 which tucks under the strip 39 the lateral edges thereof, so as to ensure higher strength of the stitched seams.
Finally, the band thus completed is moved by the rollers 70 , 74 of the traction assembly 49 with an intermittent advancement in the manner described above and is wound onto the takeup reel 75 .
The described apparatus therefore achieves the intended aim and objects. In particular, it is noted that any differences in the advancement of the band 17 due to the continuous traction performed by the punching device 18 , with respect to the intermittent traction performed by the traction assembly 49 , are absorbed effectively by the elasticity of the textile material of which the band 17 is made. In any case, the punching device can be controlled kinematically by the traction assembly in order to ensure constant advancement of the band 17 .
The described invention is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims.
The disclosures in Italian Patent Application No. BO2007A000061 from which this application claims priority are incorporated herein by reference. | An apparatus for manufacturing multilayer articles, comprising a first feeder for feeding a band made of textile material, a punching device arranged downstream of the first feeder to form slots in the band, a second feeder for feeding a strip of textile material arranged downstream of the punching device to arrange the strip so as to cover the slots, a sewing apparatus arranged downstream of the second feeder to fix the strip onto the band so as to cover the slots and provide a multilayer article, and a traction assembly arranged downstream of the sewing apparatus to actuate the advancement of the article through the sewing apparatus toward a collection unit. | 3 |
BACKGROUND INFORMATION
AC bridges (rectifiers) are used for rectification of three-phase or AC automotive generators (dynamos). Semiconductor diodes having a pn junction of silicon are generally used as rectifying elements. For example, six semiconductor diodes are wired together to form a B6 bridge in a three-phase generator. Diodes are occasionally also used in parallel circuits, using twelve diodes instead of six, for example. Suitably adapted diode bridges are also used in AC generators having a different number of phases.
These diodes are designed for operation at high currents or current densities of more than 500 A/cm 2 and high temperatures or a maximum barrier layer temperature Tj of approximately 225° C. The voltage drop in the forward direction, i.e., forward voltage UF, typically amounts to about 1 volt at the high currents used. Generally only a very low reverse current IR flows during operation in the reverse direction below breakdown voltage UZ. The reverse current increases drastically beyond breakdown voltage UZ. A further increase in voltage is therefore prevented. Z diodes having reverse voltages of approximately 20-50 volts, depending on the vehicle electrical system voltage of the particular motor vehicle, are used in most cases. Z diodes are capable of carrying high currents briefly in a breakdown. They are therefore used to limit the overshooting generator voltage in load changes (load dump). Such diodes are generally packaged in sturdy press-fit diode housings such as those described in DE 195 49 202 B4, for example.
The forward voltage of pn diodes results in forward power losses and thus has a negative effect on the efficiency of the generator. On the average, two diodes are always connected in series in current output by the generator, so the average forward power losses with a 100 A generator amount to approximately 200 W. These losses result in heating of the diodes. The resulting heat must be dissipated to the ambient air or cooling air through complex cooling measures involving the rectifier, for example, using cooling elements and/or a fan.
German Published Patent Application No. 10 2004 056 663 describes the use of so-called high-efficiency Schottky diodes (HED) instead of pn diodes to reduce the forward power losses. High-efficiency Schottky diodes are diodes having a low forward voltage and a reverse current almost independent of the reverse voltage.
German Published Patent Application No. 10 2004 053 760 describes a trench MOS barrier Schottky diode, including an integrated pn diode, as one possible exemplary embodiment of an HED Schottky diode. Such a diode is also known as a TJBS-PN. In addition to the low forward voltage in the conducting state, this also limits the overshooting generator voltage, which may occur with sudden load changes, to uncritical values, typically to voltages of less than 30 V in 14 V systems.
Much lower forward voltages UF in the range of 0.5 V to 0.7 V are achievable using high-efficiency Schottky diodes. The efficiency and power output of the generator are increased due to the low forward power losses of these diodes. The expenditure for cooling may also be reduced substantially in comparison with the use of pn diodes due to the lower power losses.
Due to the breakdown voltage of an HED, the generator voltage, which rises when a load dump occurs, is limited. High electric powers are converted into heat on the diode for a short period of time, typically less than a few 100 milliseconds. In the case of a TJBS-PN, the integrated pn structures act as voltage-limiting Z diodes. The pn structures are operated in avalanche breakdown. The power drop at the diode corresponds to the product of the reverse voltage of the diode and the generator current. Due to the high power loss, the diode heats up to very high temperatures during this process. Barrier layer temperatures or junction temperatures Tj of more than 225° C. may occur. Since the avalanche breakdown voltage VZ increases with the temperature, the voltage actually occurring during the load dump is a few volts higher than reverse voltages VZ measured at low current densities and at room temperature. As a result, in the event of a breakdown, voltages of more than 30 volts may occur briefly in a 14 V vehicle electrical system. A simple drop in breakdown voltage VZ finds its limit in the voltage ripple of the generators (ripple). In modern vehicle electrical system architectures, there is a growing trend toward limiting the maximum occurring vehicle electrical system voltage to low levels, for example, to 27 V, in the event of a malfunction.
SUMMARY
A semiconductor array according to the present invention, which is also referred to below as a TJBS-PT (trench junction barrier Schottky-punch through diode), corresponds to a high-efficiency Schottky diode, whose breakdown voltage has a very low temperature coefficient or none at all and in which the temperature-induced voltage rise therefore occurs only to a slight extent or not at all.
This TJBS-PT is a high-efficiency diode having a low forward voltage and low reverse currents, based on a trench junction barrier Schottky diode, in which the voltage is limited by a punch-through effect instead of by the temperature-dependent avalanche defect. The breakdown voltage is therefore almost independent of temperature. The semiconductor array according to the present invention is preferably packed into a press-fit diode housing and used for efficient rectification in automotive AC generators. It is therefore possible to reduce the maximum voltage occurring in the vehicle electrical system in the event of a malfunction.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a cross-sectional diagram to illustrate a cell of a TJBS-PT according to one first exemplary embodiment of the present invention.
FIG. 2 shows a simple equivalent circuit diagram of a TJBS-PT.
FIG. 3 shows a cross-sectional diagram to illustrate a cell in a TJBS-PT according to a second exemplary embodiment of the present invention.
FIG. 4 shows a cross-sectional diagram to illustrate a cell of a TJBS-PT according to a third exemplary embodiment of the present invention.
DETAILED DESCRIPTION
FIG. 1 shows a cross-sectional diagram to illustrate one cell of a TJBS-PT according to a first exemplary embodiment of the present invention. The TJBS-PT shown here has a highly n+-doped silicon substrate 1 , whose doping is preferably greater than 5·10 19 cm −3 . This silicon substrate 1 has an n-doped silicon layer 2 (epi layer) having a doping concentration Nepi and a thickness Depi, into which a plurality of trenches 3 having a depth Dt and a width Wt have been introduced. The trench bottoms are preferably designed to be rounded. A rounding radius R may be set approximately. Trench depth Dt is then defined as the distance between the silicon surface and the deepest point in the trenches. Let the distance between neighboring trenches be Wm. The trenches may be in the form of islands, strips or some other shape. The side walls of trenches 3 etched into the silicon are covered with a thin p-doped silicon layer 4 having a doping concentration NA and a thickness Wp. The interior of trenches 3 is filled with highly n-doped silicon 5 having a doping concentration ND. Furthermore, a highly p-doped layer 6 having a higher doping concentration NAA than doping concentration NA of layer 4 is introduced into the upper part of p-layers 4 . In particular, the surface concentration of layer 6 is selected to be so high that it forms an ohmic contact with a metal layer 7 above it. The p- and n-doped regions 4 and 5 or 6 may be either epitactically grown silicon, polysilicon or a combination thereof. Metal layer 7 covering the surface of the array forms a Schottky contact with the surface of epi layer 2 and forms an ohmic contact with n- and p-doped layers 5 and 6 , respectively. For example, metal layer 7 may be made of nickel or a nickel silicide. Other metals or silicides are also possible, depending on the desired height of the barrier. Additional metal layers, not shown in FIG. 1 , may also be provided above metal layer 7 . These metal layers form anode A of the diode. Substrate layer 1 is provided with an ohmic metal layer 8 , which functions as cathode K on the rear side. Again, additional metal layers, not shown in FIG. 1 , may be situated beneath layer 8 . In addition, the front and rear sides are each to be provided with a solderable layer system for packing into press-fit diode housings. For example, a conventional solderable metal system including a layer sequence of Cr, NiV and Ag, also not shown, is applied to the front and rear sides over metal layers 7 and 8 . Additional metal layers may be provided between layer 7 and the solderable NiV layer, in particular on the front side, for example, an aluminum alloy (AlSiCu) such as that customary in silicon technology, containing copper and silicon components or some other metal system, for example, AlCu, over a thin barrier layer of TaN.
The array according to the present invention may be interpreted as a parallel circuit of Schottky diodes and npn transistor structures, as illustrated in FIG. 2 , where the Schottky diodes are formed by barrier metal 7 and n-doped epi layer 2 . Layers 5 , 4 and 2 form the emitter, the base and the collector of the npn transistor structures. The base is connected electrically to the anode or emitter metallization 7 across resistor R of p-doped layer 4 and highly p-doped layer 6 . The transistor region on the trench bottom is provided with the greatest base resistance R. In the upper part, however, close to metallization 7 , the base is actually short-circuited to the emitter.
In forward polarization, current flows off to the cathode via the Schottky barrier in epi layer 2 between trench regions 3 over substrate 1 . The forward voltage may have a lower value than is the case with a pn diode due to the choice of a suitable barrier. No noteworthy current flows through the transistor structures in the trenches.
When a reverse voltage VKA is applied, space charge zones develop in the Schottky diode as well as in the npn transistor. The electric field on metal semiconductor contact 7 - 2 is shielded due to the fact that space charge zones propagate from the opposing trench walls and finally come into contact with each other. The electric field strength at the Schottky contact is therefore lower. The Schottky diodes therefore have little or no barrier-lowering behavior. The Schottky diode thus acts like a TMBS diode or a TJBS diode, in which the reverse current increases only slightly with an increase in the reverse voltage. In npn transistor substructures, the base-collector junction is polarized in the reverse direction when VKA is applied.
In npn transistors, the space charge zone expands mainly in more weakly n-doped region 2 but also extends into more strongly p-doped base region 4 . The electric fields and extents of the space charge zones at the npn transistors are at the maximum at the trench bottom, in particular in the curved region.
Breakdown voltage BVCER between the collector and emitter having resistor R between the base and emitter of a bipolar transistor is lower than avalanche breakdown voltage BVCBO of the collector-base diode because of its current gain. The breakdown voltage will usually have a positive temperature coefficient if the breakdown voltage of the collector-base diode is determined by the avalanche effect. A slightly negative-to-neutral temperature coefficient of the BVCER voltage is achievable if the diffusion profile of the transistors is designed in such a way that the space charge zone extends through base region 4 , even before achieving the avalanche breakdown voltage, and abuts against emitter region 5 (punch-through), thus limiting the voltage.
The dopings and dimensions of the semiconductor layers are designed in such a way that the breakdown voltage of the collector-base junction of the npn transistor formed from layers 2 and 4 is limited by the punch-through effect. Punch-through refers to the state in which the space charge zone of the collector-base junction polarized in the reverse direction extends completely through base layer 4 and abuts against emitter layer 5 . When the space charge zone has reached the emitter layer, current flows after overcoming another low voltage, which corresponds approximately to a forward voltage or diffusion voltage of a diode. No further voltage increase is then possible. Since the voltage limitation has virtually no dependence on temperature, in contrast with an avalanche breakdown, the breakdown voltage of an array according to the present invention does not increase with an increase in spontaneous heating.
Since the emitter-base diode is operated more or less in the forward direction, punch-through breakdowns at low currents even have a slightly negative temperature coefficient of the breakdown voltage. At high current densities and high temperatures, electron mobility decreases slightly, and for charge carriers in the space charge zone, the saturation rate drops slightly, so that temperature compensation for the reverse voltage is almost achievable.
The transition between avalanche operation and punch-through operation may be influenced through the choice of base doping NA and thickness Wp of p-doped silicon layer 4 . At a fixed thickness Wp, the avalanche effect increases with an increase in base doping NA, i.e., there is an increasingly positive temperature coefficient. The effects may be combined through a suitable choice of parameters, in such a way that the breakdown voltage becomes completely independent of temperature.
The following shows a design example for an array according to FIG. 1 having a reverse voltage of approximately 24.5 V at high current densities of approximately 400 A/cm 2 . The temperature coefficient here is almost zero between 25° C. and 200° C. According to this design example, the parameters are selected as follows:
chip thickness: Cd=200 μm; substrate doping: Nsub≧1·10 19 cm −3 ; doping concentration of epi layer 2 : Nepi=2.86·10 16 cm −3 ; thickness of epi layer: Depi=2 μm; depth of trenches 3 : Dt=1 μm. Dt includes a rounding radius at trench bottom of R=0.4 μm; width of trenches: Wt=1 μm; Rounding radius at trench bottom R=0.4 μm; doping of the n trench filling: ND=5·10 19 cm −3 ; doping of the p layer at the edge of trench: NA=2.7·10 17 cm −3 ; width of the p layer at the edge of trench: Wp=0.2 μm; increased doping of the p layer: NAA>5·10 18 cm −3 , for example 5·10 19 cm −3 .
Designs for other reverse voltages may of course also be found. Dopings and geometric dimensions may therefore be varied within a wide range. Furthermore, doping profiles which do not have constant doping but instead have a certain doping profile may also be selected. Furthermore, arrays in which n- and p-doped regions are switched may also be used.
FIG. 3 shows another exemplary embodiment having low reverse currents in particular. In contrast with FIG. 1 , n-doped layer 2 includes two different layers 2 a and 2 b having an altered thickness and different doping. Doping concentration Nepi 2 a of upper layer 2 a is selected to be lower than doping concentration Nepi 2 b of lower layer 2 b . Lower doping concentration Nepi 2 b may be approximately as high as doping concentration Nepi from the first exemplary embodiment, for example. Layer 2 b may be created with the aid of ion implantation of donors in an epi layer having doping concentration Nepi 2 a , followed by diffusion. The doping concentration and thus the desired reverse voltage may therefore be adjusted with a high precision.
FIG. 4 shows another exemplary embodiment having low reverse currents. Trenches 3 extend into highly doped substrate 1 . The functioning of the array shown here is similar to that of the array according to FIG. 2 .
The n- and p-doped layers 5 and 4 , respectively, may be made of doped polysilicon or epitaxially grown layers. It is also possible to create p-doped layers 4 by diffusion of acceptors from the trench surface into n-doped epi region 2 and to generate the n-doped layer again by deposition of polysilicon or epitactic growth. | A semiconductor array is described whose breakdown voltage has only a very low temperature coefficient or none at all and therefore there is little or no temperature-dependent voltage rise. The voltage limitation is achieved by a punch-through effect. | 7 |
RELATED APPLICATIONS
This divisional application claims priority to prior U.S. non-provisional application Ser. No. 09/863,928, filed 23 May 2001, now U.S. Pat. No. 7,595,015, the entire contents of which are hereby incorporated by reference, which claimed priority to prior U.S. Provisional App 60/207,019, filed 25 May 2000, the entire contents of which are herby incorporated by reference.
TECHNICAL FIELD OF THE INVENTION
The invention is in the field of starches and starch derivatives. More particularly, the invention relates to a cold-water soluble extruded hydroxyalkyl starch product, and to films, coatings, and other products composed therefrom.
BACKGROUND OF THE INVENTION
Food, pharmaceutical, and industrial films and coatings contain a polymeric base that often is supplemented with plasticizers, detacifiers, surfactants, and coloring agents. Typically used polymers include gums; cellulose derivatives or hydrolysis products; synthetic polymers such as polyvinyl alcohol, polyvinyl acetate, polyurethane, polystyrene or polyvinylpyrrolidone; gelatin; dextrins; modified cook-up-starches, and combinations of the foregoing. These polymers are often very expensive or difficult to use, or have reduced acceptance by certain segments of the consuming public. In recent years, greater emphasis has been placed on replacing all or part of these polymer systems with more economical consumer-friendly starch-based polymers.
Many starch materials have been used to make a variety of films, foams, and other industrial and food products. However, despite the variety of starch materials available, known starches generally can be somewhat unsuitable for use in these applications. For instance, native starches have two key limitations when used in films and coatings. Films made from unmodified or “reduced viscosity” starches generally are brittle, weak, cloudy, and opaque, and cooking is generally required to hydrate the starch polymers, inasmuch as native starches typically are water insoluble at temperatures at or below room temperature (25° C.). The problems of brittleness, clouding and opacity can be mitigated somewhat with a low degree of hydroxyalkylation of amylose and/or amylopectin contained in the starch to form a hydroxyalkyl starch, but still the hydroxyalkyl starch will be cold-water insoluble. Thus, such starches are not useful where heating is not available.
To overcome the problem of cold-water insolubility, the starch may be physically or chemically modified, or may be enzymatically treated. One approach known in the art is to modify the starch by using alkylene oxide reagents, such as propylene, oxide, ethylene oxide, and the like. This process generally requires the use of organic solvents, such as ethanol, which are undesired due to the additional processing costs associated with such solvents.
The prior art also has taught to hydroxyalkylate the starch using an aqueous process. The hydroxyalkyl starch thus prepared is then cooked by drum-drying or spray-drying, and is ground to be marketed as a pre-gelled or “instant” starch. While such pre-gelled starches are suitable for some applications, such starches are difficult to disperse in water in low temperatures. Starches used in film and coating applications may contain intact starch granules, which can result in poor film clarity and increased film opacity. Particularly in the case of drum-dried starches, large lumps, sometimes referred to as “fish-eyes,” are often formed. Also, the viscosity of these starches often is high, thus limiting the level of solids, which can be dispersed in an aqueous system without resulting in mixing and handling problems. Moreover, while occasionally additives such as borax, boric acid, gum arabic, and sulfate salts are added to improve wettability or dispersability, these solutions are somewhat unsatisfactory because of the additional costs required for such additional ingredients.
Attempts also have been made to formulate a pre-gelled, starch using an extruder. However, such attempts often have resulted in processing difficulties, particularly when modified starches are extruded under conditions of low moisture. For example, U.S. Pat. No. 5,849,233 discloses a method of extruding starch. This reference recognizes processing difficulties in extruding starches, and purports to teach that these difficulties can be overcome by employing as a feed starch a starch with a coarse particle size. However, the process requires additional drying and conditioning equipment, and can entail extra processing costs. Other efforts to extrude starch (e.g., as shown in International Publication WO 00/08945, U.S. Pat. No. 3,904,429 and Canadian patent, 1,286,533) have not provided a cold water soluble starch that is film-forming in aqueous solution. The invention seeks to address these shortcomings in the art.
SUMMARY OF THE INVENTION
Surprisingly, it has been found that hydroxyalkyl starches can satisfactorily be extruded without encountering the difficulties found in prior art processes or requiring the unusually coarse particle size required of the prior art. The extruded hydroxyalkyl starches prepared in accordance with the invention are cold-water soluble and film-forming in aqueous solution, and are useful in a number of applications.
In accordance with the invention, a process for preparing a cold-water soluble starch is provided. The process comprises providing a hydroxyalkyl starch, generally in granular form, and applying a shearing force to the starch in the presence of moisture in an extruder. The conditions in the extruder are controlled in a manner not heretofore known to provide a starch product that surprisingly is soluble in water at 25° C. and that is film-forming in aqueous solution. Generally, an extruder having a barrel, a die, and at least one rotating shaft is provided. The barrel includes at least first and second zones, the first zone being upstream from the second zone. The zones are typically defined by plural heads in the extruder barrel. In extruding the starch, the total moisture in the extruder is kept below about 25%. The temperature in the first zone is maintained at a level insufficient to gelatinize the starch at the moisture content in the barrel, and the temperature in the second zone is maintained at a level that is sufficient to gelatinize the starch. Additionally, the rotational speed of the shaft is controlled to impart a specific mechanical energy to the starch that is sufficient to result in a soluble extruded starch product that is capable of extrusion through the die, i.e., that is not overly tacky or otherwise not susceptible to extrusion. The extruded starch then may be cut, dried, and ground. The cold-water soluble starch thus prepared will be particularly suitable for use in connection with films, coatings, and like applications. Moreover, the invention is applicable to hydroxyalkyl starches having a conventional particle size distribution, and there is no need to use feed starch having an unusually coarse particle size.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a differential scanning calorimetry thermogram of a cold-water soluble starch prepared in accordance with the invention.
FIG. 2 is a rapid viscoanalyzer profile for a cold-water soluble starch prepared in accordance with the invention.
FIG. 3 is a side view illustrating the screw configuration shown for the extruder used in Example 1.
FIG. 4 is a side view illustrating the screw configuration shown for the extruder used in Example 2.
FIG. 5 is a side view illustrating the screw configuration shown for the extruder used in Example 3.
FIG. 6 is a side view illustrating the screw configuration shown for the extruder used in Example 4.
FIG. 7 is a side view illustrating the screw configuration shown for the extruder used in Example 5.
FIG. 8 is a representational view illustrating an extruder useful in conjunction with the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The starting feed starch used in connection with the invention is a hydroxyalkyl starch, which may be derived from any suitable plant source, such as corn, potato, wheat, rice, sago, tapioca, high amylose corn, waxy maize, sorghum, and so forth. The hydroxyalkyl starch may be obtained commercially, or a native starch may be hydroxylated in accordance with known methods, such as those described in Starch: Chemistry and Technology , Whistler, et al., ed. (1984), pp. 343-49. The hydroxyalkyl starch may be otherwise modified, before, after or during hydroxyalkylation, such as via acid hydrolysis, enzyme treatment, heat treatment, oxidation, cross-linking or the like. Preferably, the feed starch is an acid-thinned hydroxypropyl corn starch. Most preferably, the starch has a particle size distribution such that at least 90% by weight of the starch granules pass through an 80-mesh (180 micron) screen. Such starch is cold-water insoluble, and must be cooked to form a paste. The hydroxyalkyl starch should be derivatized with a substituent having from 2 to 6 carbon atoms, and the degree of substitution (DS) of the starch may be any value suitable to provide a film-forming starch.
In accordance with the invention, the feed starch is subjected to a shearing force, moisture and heat sufficient to gelatinize all or substantially all of the granules of the feed starch. The shearing force is applied by introducing the feed starch into an extruder, which, in accordance with the invention, may be a single screw extruder or a twin screw extruder or other suitable extruder. As shown in FIG. 8 , the extruder 100 generally includes a barrel 10 and a die 11 (in practice the extruder may include many other components, such as preconditioners, steam or water jackets, and numerous other components as may be conventional or otherwise suitable for use in conjunction with the invention). The extruder barrel includes at least first and second zones 12 , 13 , which generally are defined by heads in the extruder. The direction of travel is illustrated by the arrow 14 in FIG. 8 . Commercially available extruders useful in conjunction with the invention include those available from Wenger, such as the Wenger TX57 and TX144 extruders. The moisture content in the extruder barrel should be sufficient to gelatinize the starch, taking into account the moisture present in the feed starch (typically 9% to 12% by starch weight). Preferably, the moisture content is less than about 25% by weight (based on the total weight of dry starch and water in the barrel); more preferably, the moisture content is below about 22.5%; even more preferably, the moisture content is below about 20%; and even more preferably, the moisture content is below about 17.5%. The moisture may be added in the extruder preconditioner via addition of steam or liquid water. The preconditioner cylinder may be equipped with an agitator, such as a single agitator, dual agitators, or dual agitators with different speeds.
In operating the extruder, the temperature of the heads is such that the temperature in the first zone is not sufficient to gelatinize the starch, but the temperature in the second zone is sufficient to gelatinize the starch. The head temperature typically ranges from about 25° C. to 200° C. (it should be noted that the head temperature may be different from the actual temperature of the starch in the zone of the extruder). The extruder may have more than two zones; the invention may be performed in any such extruder so long as two zones meet the relationship heretofore described. More preferably, the temperature increases steadily in the extruder to thereby gradually cook the starch.
The invention also contemplates controlling the shaft speed of the extruder. The shaft speed typically ranges from 125 to 450 rpm, thus resulting in a retention time of from about 25 to 250 seconds. More generally, the shaft speed must be such as to provide a sufficient mechanical energy input that is sufficient to result in a starch product that is soluble in water at 25° C. If the specific mechanical energy input is too low, then the starch will be insufficiently hydrolyzed, leading to a starch that is not soluble. If the specific mechanical energy input is too high, the starch may become overly tacky, thus leading to problems with extrusion. Typically, the specific mechanical energy input will range from about 60 to about 150 kW/ton, although this and the other foregoing parameters may vary depending upon the extruder type.
The extruded starch product thus formed will be an extruded mass, often an extruded starch product, that may be cut, dried, and ground to have any desired particle size distribution. An optimum particle size range is between 40 to 140 mesh (100-400 microns), with fewer than 30% of the particles passing through a U.S. 200-mesh (75 microns) screen. When a product is made with such particle size distribution, the product will exhibit good wettability. The product may have a viscosity range, as measured by a Brookfield Viscometer, from 100 to 300 cp at 15% solids at room temperature. A typical RVA (Rapid Visco Analyzer) profile is shown in FIG. 2 .
The extruded starch product will be substantially free of starch granules, by which it is contemplated that the starch will be at least 95% gelatinized; this may be determined by an inspection of birefringence under a microscope using polarized light. FIG. 1 illustrates a differential scanning calorimetry thermogram at 10° C./min. from 20° to 140° C. of a mixture of one embodiment of the starch product of the invention and excess water (starch:water=1:3). No endothermic peaks normally expected for starch gelatinization are exhibited, thus signifying that the starch product is already gelatinized.
The starch product prepared in accordance with the invention also will be substantially completely cold-water soluble, i.e., soluble in water at 25° C. A method for determining solubility is described below. Other methods can be found in such publications as “Physical Properties of Extruded Wheat, Starch-Additive Mixtures,” Singh et al., Cereal Chemistry 75 (3):325-30 (1998). In accordance with a preferred method for determining cold-water solubility, 9.0 g (dry basis) product is dispersed in 291.0 g of distilled water. After stirring for 30 minutes at room temperature, two 50 ml aliquots of the mixture are transferred into two centrifuge tubes and centrifuged at 2,000 rpm in a suitable centrifuge, such as an IEC CL2 laptop centrifuge, for 10 minutes. Twenty ml of each supernatant are then transferred to pre-weighed PYREX evaporating dishes, and the dishes are then weighed. The dishes are then placed on a steam bath to be evaporated to dryness. Residues are then dried in an oven at 105° C. for at least two hours, and the dried samples with dishes are then cooled to room temperature in a desiccator for at least two hours. The dishes are then weighed and recorded as a dry sample weight. Solubility is calculated using the following formula:
Solubility=[(dry sample weight-tare)×30000]/(9.00×supernatant weight)
The product will be deemed cold-water soluble if the solubility is greater than 90%. A starch product prepared by the process of the invention may have a solubility greater than 99.0% by the method described.
The product prepared in accordance with the invention has an excellent film-forming property, and is particularly useful in connection with coatings. Films and coatings made of the product are clear, transparent, flexible, and strong at room temperatures. While it is not intended to limit the invention to a particular theory of operation, it is believed that the disruption of the starch granules leaves few granules intact to defract and defuse light, and to thereby cause opaqueness. The high shear encountered in the extruder also may realign the starch polymers in directions favorable to film-forming.
The starch product of the invention may be used in any application where a film, coating, barrier, or binding material is desired. The product also may be used in any application where filler, viscosity, solid, adhesive, or texture modification is needed, for example, in polishing/clear coat applications, oil/lipid barrier, adhesive, water or moisture or vapor barrier, oxygen barrier, or physical barrier, protective coating, encapsulation, fluidized bed purification, texture modification, flavor entrapment and preservation, flavor migration inhibition (especially from alcohol-based solvents), opaque maskings and coatings, imaging-forming films for printing, for example, edible inks, flavored coatings, colored coatings, free-standing films, tablet coatings, capsules, thickeners, materials for agglomeration, and the like. The product may be used in connection with food products, such as nut meats, ready-to-eat cereals, snack foods of many types, confections including soft-pan items, chocolate, marshmallows, pressed mints, chocolate pan pieces, and rolled pieces, molded chocolate bars, coffee beans, processed and unprocessed meats, and the like. The starch product also may be used in connection with industrial and consumer products, such as paper, corrugating board, cardboard boxes, detergents, cleaners, and the like, and in pharmaceutical applications such as tablets, tablet coatings, capsules, agglomeration ingredients, and so forth.
The product may be used in connection with other ingredients, including surfactants, polymers, fillers, and other ingredients as may be desired in a given application. As surfactants it is contemplated that those such as mono- and di-glycerides, di-acetyl tartaric esters of fatty acids, propylene glycol mono- and di-esters of fatty acids, polysorbate 60, calcium or sodium stearoyl 2 lactylate, lactyl stearate, sodium stearoyl fumarate, succinylate mono-glycerides, ethoxylated mono- and di-glycerides, and the like may be used. In certain applications, the starch may be used in conjunction with other natural polymers such as gums, cellulose derivatives, starch derivatives, starch hydrolysis products, microorganism products, or with synthetic polymers, such as polyvinyl alcohol, polyvinylacetate, polyurethane, polystyrene, polyvinyl pyrrolidone, and the like.
The product of the invention is particularly useful in connection with film-forming applications. In accordance with the invention, a film may be made by providing the starch of the invention, mixing the starch with sufficient water to solubilize the starch and, optionally but preferably including a plasticizer, such as glycerin, a polyethylene glycol, a propylene glycol, oleic acid, triacetin, or the like. The film thus prepared without any additive may have a tensile strength generally above 35 Mpa at 55-60% relative humidity and room temperature (as measured, for example, by an INSTRON apparatus equipped with a one-inch rubber-based grip).
The product also may be used in connection with an instant tack coating formulation. Such formulation preferably comprises water in an amount ranging from about 25% to about 85% by weight; the starch in an amount ranging from about 10% to about 25% by weight, and optionally a surface gloss agent; the surface gloss agent may serve to some extent as a plasticizer. Suitable surface gloss agents include, for example, maltodextrins, such as MALTRIN® M180 sold by Grain Processing Corporation of Muscatine, Iowa. When used, the surface gloss agent preferably is used in an amount ranging from about 5% to 50% by weight. More generally, any amount of water suitable to hydrate the starch and any amount of surface gloss agent suitable to impart surface gloss may be employed with or without colorants, flavoring agents, additional plasticizers, and the like.
The invention also encompasses a protective coating formulation, which generally comprises water, starch and a plasticizer and/or surfactant. Suitable plasticizers include glycerol and propylene glycol; one suitable surfactant is Polysorbate 80. These ingredients may be added in amounts suitable for their intended function.
The following Examples are provided to illustrate the present invention, but should not be construed as limiting the invention in scope.
EXAMPLE 1
Cold Water Soluble Acid-Thinned Hydroxypropyl Starch
An acid-thinned hydroxypropyl starch (B790 PURE-COTE® starch, available from Grain Processing Corporation, Muscatine, Iowa) having a moisture content of about 11% and having a particle size such that more than 90% by weight of the starch passed through a US 80-mesh screen was extruded on a Wenger TX144 Twin Screw Extruder according to the following conditions to give an expanded product. The expanded product was dried in a fluid bed dryer. The screw configuration of the extruder was as shown in FIG. 3 and was set such that the starch was cooked and sheared to an extent such that no significant amount of intact granules remained. The extrusion conditions were as follows.
1A
1B
1C
1D
1E
1F
1G
Raw Material Information
Substrate
B790
B790
B790
B790
B790
B790
B790
Dry Recipe % moisture
11.6
11.6
11.6
11.6
11.3
11.3
11.3
Feed Starch Rate (lb/hr)
4200
4275
4300
4400
4400
4500
4500
Cylinder Information
Steam Flow to Cylinder lb/hr
84
85
85
86
86
97
91
Water Flow to Cylinder lb/hr
107
107
109
108
110
113
115
Extrusion Information
Extruder Shaft Speed rpm
360
360
360
360
360
360
360
Extruder Motor Load %
79
80
78
84
80
79
78
Steam Flow to Extruder lb/hr
0
0
0
0
0
0
0
Water Flow to Extruder lb/hr
105
106
109
109
111
115
113
1 st Head Temp
101° F.
144° F.
95° F.
127° F.
95° F.
110° F.
97° F.
2 nd Head Temp
195° F.
192° F.
192° F.
190° F.
190° F.
191° F.
190° F.
3 rd Head Temp
225° F.
225° F.
225° F.
225° F.
225° F.
225° F.
225° F.
4 th Head Temp
258° F.
266° F.
274° F.
273° F.
269° F.
264° F.
265° F.
5 th Head Temp
320° F.
287° F.
312° F.
313° F.
319° F.
372° F.
306° F.
6 th Head Temp
280° F.
240° F.
200° F.
160° F.
170° F.
255° F.
265° F.
Specific Mechanical Energy
100.0
106.2
103.4
100.7
102.0
99.3
98.2
kW/ton
Product Assay
Moisture (%)
6.9
6.5
6.9
6.6
6.3
6.5
—
Solubility (%)
99.9
100
100
100
100
100
100
For each of these examples, the extruder specific mechanical energy inputs was greater than 80 kW/ton. The SME, shaft speed, temperature profile, and moisture content were used to monitor and control the extrusion process.
EXAMPLE 2
Cold Water Soluble Acid-Thinned Hydroxypropyl Starch
A hydroxypropyl starch (B760 PURE-COAT®, available from Grain Processing Corporation of Muscatine, Iowa) was extruded on a Wenger TX57 Twin Screw Extruder having the screw configuration shown in FIG. 4 and under the following conditions to yield an expanded product, which was dried in a moving grate dryer. The conditions were as follows.
2A 2B 2C 2D 2E 2F 2G Raw Material Information Substrate B760 B760 B760 B760 B760 B760 B760 Dry Recipe % moisture 10-11 10-11 10-11 10-11 10-11 10-11 10-11 Feed Starch Rate (lbs/hr) 350 350 250 270 290 310 330 Cylinder Information Steam Flow to Cylinder 12 12 12 12 12 12 12 lb/hr Water Flow to Cylinder 8 8 8 8 8 8 8 lb/hr Extrusion Information Extruder Shaft Speed rpm 350 350 250 270 290 310 330 Extruder Motor Load % 51 51 35 40 41 46 47 Steam Flow to Extruder 0 0 0 0 0 0 0 lb/hr Water Flow to Extruder 10 10 10 10 10 10 10 lb/hr 1 st Head Temp 98° F. 97° F. 96° F. 96° F. 95° F. 95° F. 97° F. 2 nd Head Temp 135° F. 136° F. 124° F. 125° F. 125° F. 126° F. 126° F. 3 rd Head Temp 144° F. 198° F. 129° F. 131° F. 132° F. 135° F. 136° F. 4 th Head Temp 179° F. 180° F. 176° F. 175° F. 175° F. 180° F. 180° F. 5 th Head Temp 292° F. 295° F. 231° F. 233° F. 233° F. 236° F. 239° F. Specific Mechanical 79 79 76 81 77 81 78 Energy kW/ton
The starches produced were substantially completely soluble (over 99%).
EXAMPLE 3
The starch used in Example 1 was extruded on a Wenger TX57 Twin Screw Extruder according to the following conditions and with the screw configuration shown in FIG. 5 .
Raw Material Information Substrate B790 Dry Recipe % moisture ~11% Dry Recipe Rate lb/hr 175 Feed Screw Speed rpm 15 Cylinder Information Cylinder Speed rpm 278 Steam Flow to Cylinder lb/hr 0 Water Flow to Cylinder lb/hr 0 Extrusion Information Extruder Shaft Speed rpm 398 Extruder Motor Load % 42 Steam Flow to Extruder lb/hr 0 Water Flow to Extruder lb/hr 11 Knife Speed rpm 459 No. of Knives 2 1 st Head Temp 77° F. 2 nd Head Temp 78° F. 3 rd Head Temp 108° F. 4 th Head Temp 133° F. 5 th Head Temp 270° F. 6 th Head Temp Die Hole Size & How many? 3 mm/15 Die Pressure psi 500 Vacuum on/off inches of vac? OFF Specific Mechanical Energy kW/ton 148
The expanded, friable product thus formed needed no drying. The product was ground on a Wiley Mill followed by an Alpine Mill to give a powder.
The powder was mixed into water at room temperature. A paste was formed, thus evidencing the gelatinized nature of the product. The paste was drawn into a thin film using a Meyer Road and then left to dry overnight at 50% relative humidity and 72° F. to form a clear, transparent film.
EXAMPLE 4
Cold Water Soluble Hydroxypropyl Starch
A cross-linked hydroxypropyl starch (B992 PURE-GEL®, available from Grain Processing Corporation of Muscatine, Iowa), and having a moisture content of about 11% was extruded on a Wenger TX52 Twin Screw Extruder according to the conditions provided below and using the screw configuration shown in FIG. 6 .
4A 4B 4C Raw Material Information Substrate B992 B992 B992 Dry Recipe % moisture ~11 ~11 ~11 Feed Screw Rate rpm 12 12 12 Cylinder Information Cylinder Speed rpm 110 110 110 Steam Flow to Cylinder lb/hr 0 0 0 Water Flow to Cylinder lb/hr 27.1 27.1 27.1 Extrusion Information Extruder Shaft Speed rpm 160 160 160 Extruder Motor Load % 29 28 17 Steam Flow to Extruder lb/hr 0 0 6.4 Water Flow to Extruder lb/hr 5.5 16.7 4.8 1 st Head Temp 2 nd Head Temp 32° C. 33° C. 42° C. 3 rd Head Temp 32° C. 33° C. 42° C. 4 th Head Temp 90° C. 90° C. 90° C. 5 th Head Temp 90° C. 90° C. 90° C. 6 th Head Temp 65° C. 65° C. 65° C. 7 th Head Temp 62° C. 57° C. 65° C. 8 th Head Temp 62° C. 57° C. 65° C. 9 th Head Temp 63° C. 63° C. 65° C. Die Pressure kPa 1720 70 2760
The extruded product, which was in the form of a condensed bead was dried on a moving grate dryer and then ground into a powder.
Each powder was mixed into water at room temperature to give pastes at 12% solids (thus evidencing the gelatinized nature of the extruded product). The pastes were evaluated for gel strength and clarity. Gel strength was determined using a Texture Analyzer, Stevens LFRA Texture Analyzer TA 1000, 1 cm diameter probe after one day refrigeration at 40° F. Clarity was determined by observation on a scale of 0 to 9, 0 being opaque and 9 being clearest. The following results were obtained.
Water
B992 Starch
Evaluation Test
Temperature
4A
4B
4C
(control)
Gel Strength
30° C.
26
25
26
*
40° C.
24
49
51
*
50° C.
50
56
60
48
65° C.
49
60
62
103
Clarity
30° C.
1
1
1
*
40° C.
3
5
4
*
50° C.
7
7
6
0
65° C.
9
8
8
8
* The control, B992 Starch, was not amenable to testing at 30° C. and 40° C.
Starch B992 was not amenable to testing at 30° and 40° because these temperatures were too low to allow this starch to gelatinize. Gel strength reflects the thickening power of a product when the product is mixed with water (generally, a higher gel strength is preferred in many applications).
EXAMPLE 5
Cold Water Soluble Hydroxyethyl Starch
A hydroxyethyl starch (K95F COATMASTER® starch available from Grain Processing Corporation of Muscatine, Iowa) and having a moisture content of about 11% was extruded on a Wenger TX57 Twin Screw Extruder under the following conditions and having the screw configuration shown in FIG. 7 .
Raw Material Information Substrate K95F Dry Recipe % moisture ~11% Dry Recipe Rate lb/hr 146 Feed Screw Speed rpm 8 Cylinder Information Cylinder Speed rpm 3498 Steam Flow to Cylinder lb/hr 0 Water Flow to Cylinder lb/hr 0 Extrusion Information Extruder Shaft Speed rpm 324 Extruder Motor Load % 32 Steam Flow to Extruder lb/hr 0 Water Flow to Extruder lb/hr 13 Knife Speed rpm 1087 No. of Knives 1 1 st Head Temp 85° F. 2 nd Head Temp 169° F. 3 rd Head Temp 175° F. 4 th Head Temp 203° F. 5 th Head Temp 245° F. 6 th Head Temp Die Hole Size & How many? 3/36 Die Pressure psi 200 Vacuum on/off inches of vac? OFF Specific Mechanical Energy kW/ton 110
The product was made into an aqueous paste containing 35% extrudate at room temperature (thus evidencing the gelatinized nature of the product). The paste was tested in a Rapid Visco-Analyzer (Newport Scientific) by monitoring the rotational viscosity and was found to have a viscosity of 1800 cP at 50° C. compared to a baseline viscosity measurement of the raw starting material of about 100 cP, thus evidencing the gelatinized nature of the extruded product. Additionally, when the paste was tested in a Rapid Visco-Analyzer by monitoring the rotational viscosity during a controlled heating of the paste, the product exhibited no gelatinization peak. The starting material exhibited a crisp, characteristic peak at 70° C.
EXAMPLE 6
Tack Coating and Cooked Products
The expanded starch from Example 1, 18 parts by weight, was blended with MALTRIN® M180 (a maltodextrin available from Grain Processing Corporation of Muscatine, Iowa), 9 parts by weight to form a dry blend. Water, 73 parts by weight, was added to a kettle and stirred with a powered mixer so as to create a vortex. The dry blend was slowly added to the vortex, and the contents were mixed for an additional 10 to 30 minutes to form an instant tack coating.
The tack coating may be applied to a dry feed product substrate, such as a corn curl, pretzels, snack mix, or like item. The product may be applied by spraying or ladling at a level of from about 1% to about 15% weight gain, including moisture. Seasonings, including savory seasonings such as Cajun, barbeque, cheese, mustard, ranch, Creole, and the like, or sweet seasonings such as sugar and pareils, may be added, and may be applied in any suitable manner, such as by hand or using a seasoning applicator. The resulting coated product preferably is dried in an oven at a temperature ranging from 300° F. to 450° F. to a moisture content of from about 3% to 5%.
EXAMPLE 7
Oil-Based Instant Costing
Soybean oil, 50 parts by weight, was added to a vessel equipped with good agitation. The cold water soluble starch from Example 1, 7 parts by weight, was added to the stirred oil and mixing was continued in order to achieve a smooth mixture. Water, 42 parts by weight, and lecithin, 1 part by weight, were added as an emulsifier and mixing was continued for 10 to 15 minutes in order to achieve a smooth mixture.
The coated product may be applied to a food substrate as discussed in Example 6. Preferably, the coated product is dried in an oven at 300° F. to 350° F. with forced air to a moisture content of from 3% to 5% in the finished product.
EXAMPLE 8
Coated Peanut Products
A dusting mixture was prepared by dry-blending together the product of Example 1, 50 parts by weight, and MALTRIN® M100 (a maltodextrin available from Grain Processing Corporation, Muscatine, Iowa), 50 parts by weight. Blanched, unroasted medium runner peanuts were placed in a 16″ ribbed candy pan rotating at 20 to 25 RPM. A 50% sucrose solution was poured into the pan in an amount effective to just wet the nuts to give about a 2% weight gain. The dusting mixture was then applied until the surfaces of the dusted nuts appeared dry, to thus give about a 5 to 6% weight gain. The dusted nuts were then tumbled an additional 2 to 3 minutes, during which time they wet back. An additional dusting with the dusting mixture was administered in order to achieve a dry appearance. The dry appearing, dusted nuts were then recoated with the sucrose solution, and the resulting rewetted nuts were dusted to dryness again with the dusting mixture. This alternating procedure of wetting with the sucrose solution followed by dusting to dryness with the dusting mixture was repeated until a final dry appearing dusted nut resulted having a 75 to 100% weight gain as compared to the starting peanuts. The coated nuts were roasted in an oven at 300° F. for 40 minutes with occasional stirring to assure uniformity of the roast. The roasted coated nuts were cooled to room temperature and placed back into the ribbed pan rotating at 20 to 25 rpm. Subsequently, the instant tack coating formulation from Example 6 was sprayed onto the roasted coated nuts to provide approximately 0.5% weight gain in a rotating pan in order to create a slight tackiness. McCormick Barbecue Seasoning F76161, 6% to 8% weight gain was added, and the coated nuts were tumbled until the seasoning was well distributed.
The resulting coated product was dried in an oven to a moisture level of from 3% to 5%.
EXAMPLE 9
Trail Mix Coating and Product
A mixture was prepared by dry-blending together sugar, 25 parts by weight, the product of Example 1, 15 parts by weight, MALTRIN QD® M500 (a maltodextrin available from Grain Processing Corporation, Muscatine, Iowa), 5 parts by weight, and lecithin, 0.2 parts by weight. Water, 54.8 parts by weight, was added to a kettle and stirred with a powered mixer so as to create a vortex. The dry blend was slowly added into the water at the top edge of the vortex, and the contexts were mixed for an additional 10 minutes to form an instant trail mix coating.
The resulting coating was sprayed onto a commercially purchased trail mix, by a spray gun system in a tumbler at a level of 5% to 15% weight gain. The resulting coated trail mix was dried in an oven at 150° F. to a moisture content of 10 to 12%.
EXAMPLE 10
Tablet Coating
A coating for a ⅜″ round lactose/micro-crystalline cellulose placebo tablet was made. The coating had the following composition.
Formulation
Ingredients
Percentage by Weight
Product from Example 1
12.0%
Water
88.0%
100.0
To prepare the coating, the starch was mixed into water with good agitation. A Vector HiCoater HC 100 coating pan with 2 spraying guns was used to apply the coating onto the tablets to result in a 2% weight gain on the tablet. The coating pan was set at the following conditions.
Inlet temperature
60-65° C.
Exhaust temperature
38-42° C.
Pan speed
8 RPM
Process air flow
590 CFM
Spray air volume
125 atomize/50 pattern PSI
Spray rate
130-150 ml/min.
A plasticizer, such as glycerin, polyethylene glycols (PEG), propylene glycol (PG), oleic acid, triacetin, and the like can be used to improve the physical and mechanical properties of starch. Surfactants such as di-glycerides, tartaric acid esters of fatty acids, propyleneglyco mono and diesters of fatty acids, polysorbate 60, calcium or sodium stearoyl-2-lactylate, lactylic stearate, sodium stearoyl fumarate, succinylated monoglyceride, ethoxylated mono and diglycerides, and the like optionally may be used to provide hydrophilicity. Likewise, polymers of gums, cellulose derivatives, starch derivatives or hydrolysis products, and microorganism products, synthetic polymers such as polyvinyl alcohol, polyvinyl acetate, polyurethane, polystyrene, and polyvinylpyrrolidone, and so forth can be used to improve the performance of the starch, for example, by increasing the flexibility and strength of the film-coating.
EXAMPLE 11
Film Coating
A coating for a ⅜″ round lactose/micro-crystalline cellulose placebo was made. The coating had the following composition.
Formulation
Ingredients
Percentage by Weight
Product of Example 1
5.0%
Hydroxypropyl methyl cellulose
5.0%
Propylene glycol
1.0%
Polysorbate 80
0.5%
PURE-DENT ® B815 corn starch NF*
0.5%
Titanium Dioxide
2.0%
Color
0.2%
Water
85.8%
100.0
*Available from Grain Processing Corporation, Muscatine, Iowa.
To prepare the coating, the starch was mixed into water with good agitation. A Vector HiCoater HC 100 coating pan with 2 spraying guns was used to apply the starch to tablets to result in a 3% weight gain on the tablets. The coating pan was set at the following conditions:
Inlet temperature
65-70° C.
Exhaust temperature
40-45° C.
Pan speed
8 RPM
Process air flow
575-595 CFM
Spray air volume
125 atomize/50 pattern PSI
Spray rate
170-180 ml/min.
EXAMPLE 12
The properties of the starch extrusion may be characterized in part by an Extruder Solubilization Point Value (ESPV), which may be calculated as follows.
ESPV = 1.71 × 10 6 × ( M + M ws ) × D 4 ( T h - T 1 ) ( M ( Fws Cps + Fww Cpw ) + Mws Cpw ) ( Ffww 5 × M × Afg )
wherein
M=mass flow rate of starch through extruder (kg/s) Mws=flow rate of water through extruder (kg/s) D=diameter of extruder barrel (m) T h =highest head temperature in barrel (° C.) T l =lowest head temperature in barrel (° C.) Fws=weight fraction of starch in feed Fww=weight fraction of water in feed Ffww=weight fraction of water in the barrel Afg=grams of starch from viscosity test*(g) Cps=specific heat capacity of starch (J/kg) Cpw=specific heat capacity of water (4186 J/kg) *From the method disclosed in “The Estimation of Starch Paste Fluidities.” W. R. Fetzer and L. C. Kirst, J. Cereal Chem ., American Ass'n of Cereal Chemists, Vol. 36, No. 2 (U.S., March, 1959).
Preferably, the ESPV is greater than or equal to 1.0. Following is a table of extrusion conditions and ESPVs for the extruded starch of Examples 1, 2 and 3.
Inputs
Ex. 3
Ex. 1A
Ex. 1B
Ex. 1C
Ex. 1D
Ex. 1E
Ex. 1F
Ex. 1G
SME,
148
100
106.2
103.4
100.7
102
99.3
98.2
kW/ton
M, lb/hr
175
4200
4275
4300
4400
4400
4500
4500
Mws,
11
296
298
303
303
307
325
319
lb/hr
T h , deg F.
270
320
287
312
313
319
372
306
T l , deg F.
77
101
144
95
127
95
110
97
Fws
0.89
0.884
0.884
0.884
0.884
0.887
0.887
0.887
Fww
0.11
0.116
0.116
0.116
0.116
0.113
0.113
0.113
Ffww
0.163
0.174
0.174
0.174
0.173
0.171
0.173
0.172
Dia, mm
57
144
144
144
144
144
144
144
Afg
36
36
36
36
36
36
36
36
M/SME
1.18
42.00
40.25
41.59
43.69
43.14
45.32
45.62
ESPV
1.0
1.1
1.7
1.1
1.3
1.1
0.9
1.2
Ex.
Inputs
Ex. 2A
Ex. 2B
Ex. 2C
Ex. 2D
Ex. 2E
Ex. 2F
2G
SME,
79
79
76
81
77
81
78
kW/lb
M, lbs/hr
350
350
250
270
290
310
330
Mws,
30
30
30
30
30
30
30
lbs/hr
T h , deg F.
292
295
231
233
233
236
239
T l , deg F.
98
97
96
96
95
95
97
Fws
0.895
0.895
0.895
0.895
0.895
0.895
0.895
Fww
0.105
0.105
0.105
0.105
0.105
0.105
0.105
Ffww
0.176
0.176
0.201
0.195
0.189
0.184
0.180
Dia, mm
57
57
57
57
57
57
57
Afg
13
13
13
13
13
13
13
M/SME
4.43
4.43
3.29
3.33
3.77
3.83
4.23
ESPV
1.0
1.0
1.1
1.1
1.2
1.2
1.3
All of the ESPVs were above 1.0.
COMPARATIVE EXAMPLE
Unacceptably sticky products were prepared by extruding B790 PURE-COTE® starch on a Wenger TX144 Twin Screw Extruder under the following conditions.
Inputs
C-1A
C-1B
C-1C
C-1D
C-1E
SME, kW/
86.9
76.4
103.6
140
150
ton
M, lbs/hr
3800
4100
4100
3000
3000
Mws, lbs/hr
380
370
382
238
300
T h , deg F.
269
269
269
293
305
T l , deg F.
97
87
90
96
86
Fws
0.88
0.884
0.884
0.88
0.884
Fww
0.12
0.116
0.116
0.12
0.166
Ffww
0.200
0.189
0.191
0.185
0.196
Dia, mm
144
144
144
144
144
Afg
36
36
36
36
36
M/SME
43.73
53.66
39.58
21.43
20.00
ESPV
0.8
0.9
0.9
1.3
0.8
As seen, all but one of the ESPVs were below 1.0 in these examples. It is believed that, although the barrel temperature was allowed to vary in accordance with the invention, the moisture content in the barrel was too high to result in an acceptable product given the other conditions.
Thus, it is seen that the invention provides a satisfactory cold-water soluble starch. The starch may be prepared by extrusion in a conventional extruder.
While particular embodiments of the invention have been shown, it will be understood that the invention is not limited thereto since modifications may be made by those skilled in the art, particularly in light of the foregoing teachings. It is, therefore, contemplated by the appended claims to cover any such modifications as incorporate those features, which constitute the essential features of these improvements within the true spirit and scope of the invention. All references cited herein are hereby incorporated by reference. | Disclosed is a cold-water soluble starch and a process for preparing same. Generally, the process comprises providing a hydroxyalkyl starch and applying a shearing force to the starch in an extruder in the presence of moisture, the force and the moisture each being sufficient to gelatinize at least substantially all of the granules of the starch to thereby form a sheared starch. The starch is heated to its gelatinization temperature after the starch has passed partially through the barrel of the extruder, with the moisture being maintained at a level sufficiently high to allow gelatinization but sufficiency low to protect the starch from becoming too sticky to extrude. The extruded starch product thus formed may be used in connection with a number of film-forming, coating, and other applications. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0001] (Not applicable)
REFERENCE TO SEQUENTIAL LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING APPENDIX SUBMITTED ON A COMPACT DISC
[0002] (Not applicable)
BACKGROUND OF THE INVENTION
[0003] 1. Field of the Invention
[0004] The present invention relates to concrete construction utilizing foam block forms, more specifically to improvements to the foam sidewalls used to create a longitudinally bi-directional system, improved form sidewall spacing ties which create enhanced concrete flow, enhanced strength, and enhanced fire-break properties, and a corner form that can be used as a right-hand or left-hand form.
[0005] 2. Description of the Related Art
[0006] Concrete forms made of a polymeric foam material are known. Such forms basically comprise a pair of laterally spaced-apart sidewalls presenting a cavity therebetween. A number of these forms are connected to present longitudinally and vertically aligned cavities for pouring concrete therein.
[0007] One such form is shown in U.S. Pat. No. 3,788,020, issued on Jan. 29, 1974. This patent discloses a concrete form with a pair of sidewalls, end walls and intermediate partition walls. A plurality of these forms are connected to present vertical cavities for pouring concrete therein to form a plurality of vertical concrete columns or piers. These vertical columns are connected by a horizontal concrete beam formed by filling a channel with concrete, the channel presented upon placing one row of concrete forms atop another.
[0008] One problem with existing concrete forms is that the sidewalls must be immobilized so as to resist pressures on the walls during transport and, more importantly, during concrete pouring and curing. If not, the form sidewalls may shift in lateral and/or vertical and/or longitudinal directions. Such displacements make it difficult to easily connect the forms. Also, the forms may separate along the joints respectively presented along the zones of connection between longitudinally and vertically adjacent forms. If the forms are not sufficiently braced, the concrete can cause these joints to separate. The industry refers to such separations as “blow outs”.
[0009] During the pouring of the concrete, a hydraulic concrete load acts on the sidewalls of each form as well as on any structure spanning such sidewalls. The load urges the sidewalls from their proper vertical, lateral and longitudinal spatial relationships. Also, during form transport to the job site, the sidewalls may be displaced due to the weight of other forms stacked thereon. In some cases the distance between the sidewalls may vary. Accordingly, problems will arise when attempting to longitudinally and vertically connect forms as the mating lap joint surfaces and/or tongue/groove elements will not be properly aligned.
[0010] The closest related publications known to the inventor are U.S. Pat. No. 4,223,501 granted to DeLozier Sep. 23, 1980 and Published U.S. Application 2004/0045237 invented by Coombs et al and published Mar. 11, 2004. Each of these publications shows concrete forms made of opposing panels. The panels are held in spaced relationship by ties. In the patent publication, the tie contains inadequate open space to allow for the free flow of concrete necessary during a pouring operation in order to avoid air pockets which will weaken the resulting wall. In both of these publications, the tie is a single piece bent at each side to form an anchor. This allows for lateral movement during shipping and a corresponding loss of alignment. When this happens the units do not fit together properly on the construction site.
[0011] Also, in both of these publications, the tie is made of metal, which conducts heat and can be a mode of transmitting heat during fire. Additionally, in both of these publications there is no predetermined space for connecting the form to studs.
[0012] As seen from the above, various devices in the forms of braces and permanent tension members have been proposed so as to maintain the sidewalls in place to preclude such shifting and/or “blow outs” during concrete pouring and subsequent curing. However, such devices have been relatively complex in construction requiring the sidewalls to have special configurations so as to receive the braces and/or ties and have lacked desirable features.
[0013] In prior art systems, comers present some problems. Typically a wall form is extended to the end of the wall and a piece of foam plastic is secured over the end of the wall form by wire or the like.
[0014] This type of end is difficult to secure to the wall form, frequently breaks during concrete pouring, and is not securely fastened to the wall form. This creates unnecessary labor in fixing breaks, setting up the forms, and affixing exterior sheathing to the corner of the wall.
[0015] In another prior art approach, the specific corner form is provided, but it is preformed for a certain specific job and must be either a right-hand corner or a left-hand corner. Right-hand or left-hand orientation is always determined from a top plan view because these forms have by necessity a top end and a bottom end. Therefore, a right-hand corner form cannot be substituted for a left-hand corner and visa versa. This doubles the number of types of molds required to produce the corner forms, doubles the types of corner forms needed in inventory, increases delivery costs, and so forth.
[0016] Therefore, there is a need for a corner form for a concrete wall that is universal, that is, can be used for either a right-hand or left-hand wall corner; that can be securely and easily attached to the wall form; that does not break during concrete pouring; and that is securely fastened to the wall form.
BRIEF SUMMARY OF THE INVENTION
[0017] The present invention is directed to maintaining the positive aspects of the advances already made by the prior art while eliminating the problem areas. Thus, the inventor has invented improvements in concrete forms.
[0018] A particular object of this invention is to provide a concrete form bi-directional system which enhances on-site assembly of the concrete form walls. This improvement takes the form of a bi-directional insulating concrete form system having novel upper, lower, and side surfaces that provide one-hundred eighty degree rotation of the form creating a bi-directional orientation for corresponding insulating concrete forms. Forty-five and ninety degree corner blocks are also part of this invention.
[0019] One improvement disclosed in this invention is a corner form for a concrete wall. This form creates a universal corner form, that is, it can be used to create right-hand or left-hand wall corners in concrete walls. Another feature of this corner form is that it can be securely and easily attached to the wall form. Another feature of this corner form is that it can provide a corner form for a concrete wall that does not break during concrete pouring. This corner form for a concrete wall is securely fastened to the wall form.
[0020] Another improvement over the prior art is a form tie, more particularly, novel form ties for maintaining the sidewalls of a concrete form in desired longitudinal, vertical and laterally spaced-apart relationships that also serve as a fire-break. Each form tie generally comprises a pair of plastic vertical side pieces with a pair of metal horizontal pieces spanning the form sidewalls. The ties are formed by connecting a pair of plastic vertical side pieces with a pair of metal horizontal pieces. The horizontal pieces are located at the upper and lower ends of the vertical pieces. The vertical side pieces are embedded in the sidewalls of the forms during the molding process with the horizontal pieces spanning the facing interior surfaces of the sidewalls. The ties preclude lateral, vertical and longitudinal shifting of the sidewalls during transport and use. The ties of the present invention find use in concrete forms and effectively interface with the form sidewalls so as to maintain the walls in a desired spatial relationship during transport as well as concrete pouring and curing. The forms of the present invention also automatically present a longitudinally enhanced fire-break resulting from the innovative use of metal band horizontal pieces and thermoplastic vertical side pieces. During a fire, the thermoplastic vertical side pieces melt and do not conduct heat to the horizontal pieces. Thus, the heat stays on one side of the enclosed concrete. Also, the ties are oriented to reduce downward stress on the ties, as a whole, during the pouring of plastic concrete in the cavity formed between the sidewalls.
[0021] The ties resist loads that impart tension, compression, bending, twisting and lateral stresses acting thereon. The ties also diminish the lateral, vertical and longitudinal displacement of adjacent sidewalls of a concrete form during transport and use. The ties of the present invention further enhance on-site assembly of the concrete forms, inclusive of the installation of exterior finish materials attached thereto. These ties effectively resist the forces arising from concrete flow but without interference with the concrete flow in the cavity between the form sidewalls and between adjacent forms.
[0022] Other objects and advantages of this invention will become apparent from the following description taken in connection with the accompanying drawings, wherein is set forth by way of illustration and example, now preferred embodiments of this invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is an elevational perspective view of an elongated concrete form of the present invention.
[0024] FIG. 2 is an elevational top view of the elongated form shown in FIG. 1 .
[0025] FIG. 3 is an elevational perspective view of one embodiment of an elongated form sidewall of this invention.
[0026] FIG. 4 is an elevational end view of the elongated form sidewall of FIG. 3 .
[0027] FIG. 5 is an elevational top view of the elongated form sidewall of FIG. 3 .
[0028] FIG. 6 is an elevational side view showing the inside of the elongated form sidewall of FIG. 3 .
[0029] FIG. 7 is an elevational perspective view of another embodiment of an elongated form sidewall of this invention.
[0030] FIG. 8 is an elevational end view of the elongated form sidewall of FIG. 7 .
[0031] FIG. 9 is an elevational top view of the elongated form sidewall of FIG. 7 .
[0032] FIG. 10 is an elevational side view of the elongated form sidewall of FIG. 7 .
[0033] FIG. 11 is an elevational end view of an elongated form of this invention.
[0034] FIG. 12 is an elevational perspective view of a part of an elongated form sidewall showing a male connection.
[0035] FIG. 13 is an elevational perspective view of a part of an elongated form sidewall showing a female connection.
[0036] FIG. 14 is an elevational perspective view of an elongated form of the present invention showing the contours of the form.
[0037] FIG. 15 is an elevational top view showing a corner form of this invention in place.
[0038] FIG. 16 is an enlarged elevational top view of a portion of a first sidewall shown in FIG. 15 , showing the male connection in detail.
[0039] FIG. 17 is an enlarged elevational top view of a portion of a second sidewall shown in FIG. 15 , showing the female connection in detail.
[0040] FIG. 18 is an elevational perspective view of a corner form of this invention.
[0041] FIG. 19 is an enlarged detail view of the corner of the form of FIG. 18 .
[0042] FIG. 20 is an elevational side view of the open side of the form of FIG. 15 .
[0043] FIG. 21 is an elevational side view of the closed side of the form of FIG. 15 .
[0044] FIG. 22 is an elevational side view of the form of FIG. 15 from the right end of the form.
[0045] FIG. 23 is an enlarged detail view showing the top end of the form as seen in FIG. 22 .
[0046] FIG. 24 is an enlarged detail view showing the bottom end of the form as seen in FIG. 22 .
[0047] FIG. 25 is an elevational top view of a corner form sidewall of this invention.
[0048] FIG. 26 is an enlarged elevational top view showing the male edge of the form sidewall of FIG. 25 .
[0049] FIG. 27 is an enlarged elevational top view showing the female edge of the form sidewall of FIG. 25 .
[0050] FIG. 28 is an elevational perspective view of a corner form sidewall of the present invention.
[0051] FIG. 29 is an enlarged elevational perspective view showing the top corner of the corner form sidewall of the present invention.
[0052] FIG. 30 is an elevational side view of a corner form sidewall of this invention.
[0053] FIG. 31 is an enlarged side elevational view of the top portion of the corner form sidewall shown in FIG. 30 .
[0054] FIG. 32 is an enlarged elevational side view of the bottom portion of the corner form sidewall shown in FIG. 30 .
[0055] FIG. 33 is an elevational side view of a first corner sidewall section for a form of this invention.
[0056] FIG. 34 is an enlarged elevational side view of the top end of the section of FIG. 33 showing detail.
[0057] FIG. 35 is an enlarged elevational side view of the bottom end of the section of FIG. 33 showing detail.
[0058] FIG. 36 is an elevational end view of a corner sidewall of this invention.
[0059] FIG. 37 is an enlarged elevational end view of the corner shown in FIG. 36 showing detail.
[0060] FIG. 38 is an elevational perspective view of a corner sidewall.
[0061] FIG. 39 is an elevational perspective view of a top corner section of a corner sidewall shown in FIG. 38 showing detail.
[0062] FIG. 40 is an elevational top view of a corner sidewall of this invention.
[0063] FIG. 41 is an elevational top view of a first end of the corner sidewall of FIG. 40 showing detail.
[0064] FIG. 42 is an elevational top view of a second end of the corner sidewall of FIG. 40 showing detail.
[0065] FIG. 43 is an elevational side view of a tie of the present invention
[0066] FIG. 44 is an elevational front view of a tie of the present invention
[0067] FIG. 45 is an elevational perspective view of a tie of the present invention.
[0068] FIG. 46 is a top cross-sectional view of a form of one embodiment having ties attached thereto.
[0069] FIG. 47 is a front cross-sectional view of a form of one embodiment having ties attached thereto.
[0070] FIG. 48 is an end cross-sectional view of a pair of concrete form sidewalls of this invention having ties attached thereto.
[0071] FIG. 49 is an elevational perspective view of a sidewall of one embodiment of this invention having ties attached thereto.
[0072] FIG. 50 is an elevational perspective view of a wall using the forms of this invention under construction.
[0073] FIG. 51 is an elevational perspective view showing the placement of a bottom layer of forms in a wall.
[0074] FIGS. 52 and 53 are cross-sectional views of the forms of this invention having rebars passing through poured concrete and inner and outer finishing.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0075] The invention will now be described with reference to the above drawings wherein like reference numerals refer to like parts throughout the description.
[0076] Turning more particularly to the drawings, FIGS. 1-14 , show one type of longitudinal concrete form 2 which comprises a pair of rectangular sidewalls 4 . These sidewalls 4 are preferably made of fire-resistant foamed plastic. Each sidewall 4 has upper 6 and lower 8 longitudinal surfaces as well as a pair of opposed vertical surfaces 10 . Each sidewall 4 has an inner surface 12 and an outer surface 14 . When the longitudinal form 2 is assembled, the inner surfaces 12 of the sidewalls 4 cooperate to form a plurality of vertical cavities 16 and a vertical slot 18 . The slot 18 longitudinally spans the length of the form 2 and connects the cavities 16 . The outer surface 14 is flat and serves to receive facing or studs.
[0077] As shown best in FIG. 11 , each sidewall 4 ′, 4 ″ has a raised portion 20 and a non-raised portion 22 along the upper surface 6 which mate with a complementary non-raised portion 22 and raised 20 portion located along the lower surface 8 of an overlying form 2 . In each sidewall 4 ′ 4 ″, the vertical surfaces 10 ′, 10 ″ as shown best in FIG. 2 are made up of a tongue 24 and groove 26 . For a first (outer) sidewall 4 ′, a first vertical surface 10 ′ has a tongue 24 and the second vertical surface 10 ″ has a corresponding groove 26 . For the second (inner) sidewall 4 ″ of a form 2 , the sidewall 4 ″ opposite the first sidewall 4 ′, the first vertical surface 10 ′ has a groove 26 and the second vertical surface 10 ″ has a tongue 24 as best seen in FIGS. 12 and 13 . Accordingly, the forms 2 may be connected in longitudinally extending courses and stacked one atop the other. In the above, “outer” and “inner” are related to the exterior or interior of the building. This is best shown in FIGS. 50 and 51 .
[0078] Referring to FIGS. 50 and 51 , the first course of longitudinal forms 2 is positioned atop a footing 28 and held in place by various materials such as plastic roof cement. It is understood that other types of connection of the first row of longitudinal forms 2 to the footing 28 may be utilized, such as placing the forms 2 in a wet footing 28 and allowing the footing 28 to subsequently dry. Upon reaching a desired height of the forms 2 , wet concrete is poured between the form sidewalls 4 . From FIG. 50 , it is seen that the forms 2 are staggered among rows so as to preclude formation of a continuous vertical joint among the form rows. The poured concrete fills the vertical cavities 16 and longitudinally extending vertical slot 18 of each form 2 . Also, upon stacking a second course of forms 2 atop the first course of forms 2 , a horizontal channel is formed which spans the upper and lower forms 2 . The poured concrete will fill the channel of the form 2 . Thus, a concrete wall within the interior of the forms 2 is presented. The forms 2 are left in place for insulating the resulting concrete wall. Wall clips (not shown) may be used for attaching exterior siding thereto. Such clips are the subject of a separate patent application by the inventor.
[0079] It is known that the courses of the forms 2 may be selectively configured so as to present walls of various configurations. Also, door frames, window frames, bucks, bulkheads, and the like may interrupt the courses of forms 2 so as to provide openings for insertion of doors, windows and the like therein while precluding spillage of poured concrete from the forms 2 .
[0080] Referring to FIGS. 15-42 , corner forms 30 of this invention will be described. There is shown a universal corner form 30 for concrete walls. By universal corner form 30 , it is intended to mean that there is an open left-hand side 32 of the corner form 30 or an open right-hand side 34 which can fit onto either end of the forms 2 of the present invention.
[0081] As can best be seen in FIGS. 15-17 , the vertical surfaces 36 of the corner form 30 are the same as the vertical surfaces 10 of the sidewall forms 2 . Also, the upper 6 and lower 8 longitudinal surfaces of the corner pieces 30 are configured identically to the upper 6 and lower 8 surfaces of the sidewall forms 2 .
[0082] With reference to the sidewall form 2 shown in FIG. 14 , it may be assumed that the sidewall 4 which has the tongue 24 on the vertical surface 10 is the outer sidewall 4 ′ while the sidewall 4 which has the groove 26 on the vertical surface 10 is the inner sidewall 4 ″.
[0083] In order to make a left corner using the above form, the open right-hand side 34 of the corner form 30 as shown in FIG. 15 is connected to the above form 2 . Similar straight forms 2 may then be connected to the open left-hand side 32 of the corner form 30 . In such an arrangement, the upper longitudinal surface 6 of both the straight forms 2 and the corner forms 30 will contain raised portions 20 along the outer surface 14 and non-raised portions 22 along the inner surfaces 12 .
[0084] In a like manner, to form a right corner using the above corner form 30 , the open left-hand side 32 of the corner form 30 shown in FIG. 15 is connected to the above straight form 2 . Again, straight forms 2 may be connected to the free end of the corner form 30 . In such an arrangement, the upper longitudinal surface 6 of both the sidewalls 4 and the corner pieces will contain raised portions 20 along the outer surface 14 and non-raised portions 22 along the inner surfaces 12 .
[0085] Should the straight form 2 be in place such that the outer sidewall 4 ′ contains an upper longitudinal surface 6 having a raised portion 20 along inner surface 12 and a non-raised portion 22 along the outer surface 14 , the corner form 30 may simply be turned over so that the former upper longitudinal surface 6 is now the lower longitudinal surface 8 . The corner form 30 will then have an outer sidewall 4 ′ which contains an upper longitudinal surface 6 having a raised portion 20 along inner surface 12 and a non-raised portion 22 along the outer surface 14 . This allows the corner form 30 of the present invention to be a universal corner form as it can form a left corner or right corner regardless of the configuration of the vertical surfaces of the sidewalls 4 of the form 2 .
[0086] Referring to FIGS. 43-49 , the ties 38 of this invention are described. Each tie 38 presents an overall square or rectangular configuration. The tie 38 comprises first and second laterally spaced-apart vertical thermoplastic side pieces 40 with two connecting metal horizontal pieces 42 therebetween.
[0087] Each side piece 40 generally comprises a vertical holder 44 having a proximal edge 46 and a distal edge 48 . The proximal edge 46 is of lesser length than the distal edge 48 . The vertical holder 44 contains a plurality of holes 50 to allow the passage of polystyrene beads and to avoid the buildup of air pockets in the vicinity of the tie 38 . The side piece 40 contains a vertical flange 52 laterally displaced from each side of the proximal edge 46 of the vertical holder 44 . The presence of two flanges 52 gives added dimensional stability and strength to the prepared form 2 .
[0088] A horizontal piece 42 in the form of a thin metal band extends between approximately the midline between the proximal edge 46 and the distal edge 48 of a first vertical holder 44 and approximately the corresponding midline of a second vertical holder 44 at the lower ends 54 thereof. Likewise, upper ends 56 of first and second vertical holders 44 are similarly joined by a metal horizontal piece 42 . The horizontal pieces 42 may be secured to the vertical holders 44 by common fastening devices, preferably rivets. Dimensional stability may be assured by having the horizontal pieces 42 fit into grooves 58 in the vertical holders 44 . Complimentary notches 60 and protrusions 62 in the horizontal pieces 42 and the vertical holders 44 serve to increase lateral and vertical dimensional stability of the tie 38 and any form 2 containing the tie 38 . The thin metal band horizontal piece 42 is located such that the upper 64 and lower surfaces 66 are narrow and the two side surfaces 68 are wide.
[0089] In the event of a fire on a first side of a concrete wall prepared using the ties 38 and forms 2 of the present invention, the thermoplastic side pieces 40 melt and cannot transfer sufficient heat to the metal horizontal pieces 42 to allow the fire to spread to the opposite side of the concrete wall.
[0090] As is known in the prior art, two bipartite molds are used for forming the sidewalls of the polymeric concrete form. Polystyrene beads are blown into the respective sidewall molds at a first temperature with the beads expanding upon cooling so as to fill the mold. Upon the beads being reheated at an elevated temperature, a second expansion occurs so that the foam fills the mold. Upon removal of the mold the sidewalls 4 are presented.
[0091] One problem which has arisen with the use of form ties is that the sidewall molds must have openings therein to allow for insertion of the ends of the tie in each mold and extension of the tie between the sidewall molds. In turn, the expanding foam may escape from these mold openings. Such a leakage/seepage of the foam from the mold may impair form integrity and lead to undesirable ruptures, cracks, etc. in the forms. Such defects may not be visibly apparent until the form sidewalls are subjected to the hydraulic loads presented by the poured concrete between the form sidewalls.
[0092] In response to such a problem, the vertical side pieces 40 of the ties 38 of this invention are configured to seal the mold openings. The forms 2 are prepared as a unit with the ties 38 being embedded in the sidewalls 4 . Thus, the vertical side pieces 40 preclude escape of the expanding polystyrene foam from the mold. Also, the distance between these vertical side pieces 40 defines the length of the horizontal pieces 42 and thus the resulting lateral displacement between the sidewalls 4 . Accordingly, the coplanar relationship of the opposed, interior surfaces 12 of the sidewalls 4 presents a visual gauge of a common lateral displacement between the sidewalls 4 of the forms 2 .
[0093] Thus, the horizontal pieces 42 fix and maintain a desired lateral distance between the interior surfaces 12 of the sidewalls 4 of the form 2 . This common lateral modularity assures the builder that the stacked forms will present even exterior surfaces
[0094] As best shown in FIGS. 46-49 , the ties 38 are embedded in the sidewalls 4 of the form 2 . As such, they resist any forces acting thereon which may disrupt the monolithic structure of the sidewall 4 . The horizontal pieces 42 span the sidewalls 4 . As such, a plurality of horizontal pieces extends between the sidewalls 4 so as to maintain the distance therebetween in the presence of hydraulic concrete loads. It is noted that the horizontal pieces 42 are so arranged as to present a minimal amount of surface to a longitudinal concrete flow through the form 2 .
[0095] The ties 38 , as above described, resist tension, compression, bending, twisting and lateral forces acting thereon during transport as well as during concrete pouring and curing.
[0096] Thus, longitudinal shifting of the sidewalls 4 of the form 2 is particularly precluded. Such preclusion also contributes to the elimination or reduction in the width modularity during form use.
[0097] Referring to FIGS. 52 and 53 , following construction of the form wall and prior to the pouring of the concrete, horizontal rebars 70 are placed on the upper surface 64 of one lower horizontal piece 42 and the corresponding surface 64 of the other lower horizontal pieces 42 of the ties 38 . Following the installation of horizontal rebars 70 , vertical rebars 72 are installed offset from the center of the form 2 to lend support to the concrete wall. Following the installation of vertical rebars 72 , the vertical 72 and horizontal 70 rebars are tied into place.
[0098] As best seen in FIGS. 3-10 , some of the inner sidewalls 4 ″ contain notches 96 on the upper longitudinal surface 6 thereof. These notches 96 may hold the short side of L-shaped pieces (not shown). The long side of such pieces will fit against the outer surface 14 of the sidewalls 4 . The configuration of the short side of the L-shaped piece is such that it completely fills the notch 96 . The configuration of the long side of the L-shaped piece is such that it will lie flat along the outer surface 14 of the inner sidewall 4 ″. The long side presents a solid surface to aid in nailing studs to the inner sidewall 4 ″. To this end, the distance between the notches 96 is equal to the conventional distance between studs.
[0099] It is to be understood that while certain forms of this invention and dimensions have been illustrated and described, the invention is not limited thereto except insofar as such limitations are included in the following claims and allowable functional equivalents thereof. | An insulating concrete form foam block bi-directional system comprises a pair of opposed and parallel foam sidewall panels spaced using a plurality of plastic and metal band ties that act as a fire-break between the two exterior finished concrete wall surfaces. Each tie comprises nearly full sidewall height, plastic flanges which engage the sidewalls and a metal band cross-connecting vertical holders of the ties. The metal band forms a wide opening to enhance concrete flow. The tie results in a minimal downward stress impact on the tie during concrete placement. The top and bottom surfaces of each sidewall are formed with raised areas and non-raised areas which interlock with adjacent blocks. The side surfaces of each sidewall are formed with vertical tongues and grooves which interlock with like tongues and grooves of corner pieces which are adapted to form right or left-hand comers. | 4 |
This is a divisional application of application Ser. No. 08/066,188, filed on May 21, 1993, now U.S. Pat. No. 5,411,636.
BACKGROUND OF THE INVENTION
In the manufacture of tissue products, it is generally desireable to provide the final product with as much bulk as possible without compromising other product attributes. However, most tissue machines operating today utilize a process known as "wet-pressing", in which a large amount of water is removed from the newly-formed web by mechanically pressing water out of the web in a pressure nip between a pressure roll and the Yankee dryer surface as the web is transferred from a papermaking felt to the Yankee dryer. This wet-pressing step, while an effective dewatering means, compresses the web and causes a marked reduction in the web thickness and hence bulk.
On the other hand, throughdrying processes have been more recently developed in which web compression is avoided as much as possible in order to preserve and enhance the bulk of the web. These processes provide for supporting the web on a coarse mesh fabric while heated air is passed through the web to remove moisture and dry the web. If a Yankee dryer is used at all in the process, it is for creping the web rather than drying, since the web is already dry when it is transferred to the Yankee surface. Transfer to the Yankee, although requiring compression of the web, does not significantly adversely affect web bulk because the papermaking bonds of the web have already been formed and the web is much more resilient in the dry state.
Although throughdried tissue products exhibit good bulk and softness properties, throughdrying tissue machines are expensive to build and operate. Accordingly there is a need for producing higher quality tissue products by modifying existing, conventional wet-pressing tissue machines.
SUMMARY OF THE INVENTION
It has now been discovered that the bulk of a wet web can be significantly increased with little capital investment by abruptly deflecting the wet web, at relatively high consistency, into the open areas or depressions in the contour of a coarse mesh supporting fabric, preferably by pneumatic means such as one or more pulses of high pressure and/or high vacuum. Such abrupt flexing of the web causes the web to "pop" or expand, thereby increasing the caliper and internal bulk of the wet web while causing partial debonding of the weaker bonds already formed during partial drying or dewatering. This operation is sometimes referred to herein as wet-straining. The web can then be dried to preserve the increased bulk. This discovery is particularly beneficial when applied to wet-pressing processes in which a relatively large number of bonds are formed in the wet state, but it can also be applied to throughdrying processes to further improve the quality of the resulting tissue product.
The effects of wet-straining on the web can be quantified by measuring the "Debonded Void Thickness" (hereinafter described), which is the void area or space not occupied by fibers in a cross-section of the web per unit length. It is a measure of internal web bulk (as distinguished from external bulk created by simply molding the web to the contour of the fabric) and the degree of debonding which occurs within the web when subjected to wet-straining. The "Normalized Debonded Void Thickness" is the Debonded Void Thickness divided by the weight of a circular, four inch diameter sample of the web. The determination of these parameters will be hereinafter described in connection with FIGS. 8-13.
Hence, in one aspect the invention resides in a method for making a tissue product comprising: (a) depositing an aqueous suspension of papermaking fibers onto an endless forming fabric to form a wet web; (b) dewatering or drying the web to a consistency of 30 percent or greater; (c) transferring the web to a coarse mesh fabric; (d) deflecting the web to substantially conform the web to the contour of the coarse fabric; and (e) drying the web.
In another aspect, the invention resides in a method for making a tissue product comprising: (a) depositing an aqueous suspension of papermaking fibers onto an endless forming fabric to form a wet web; (b) transferring the wet web to a papermaking felt; (c) pressing the web to a consistency of about 30 percent or greater; (d) transferring the web to a coarse fabric; (e) deflecting the web to substantially conform the web to the contour of the coarse fabric; (f) throughdrying the web to a consistency of from about 40 to about 90 percent while supported on the coarse fabric; (g) transferring the throughdried web to a Yankee dryer to final dry the web; and (h) creping the web.
In yet another aspect, the invention resides in a method for making a wet-pressed tissue product comprising: (a) depositing an aqueous suspension of papermaking fibers onto an endless forming fabric to form a wet web; (b) transferring the wet web to a papermaking felt; (c) pressing the wet web to a consistency of about 30 percent or greater; (d) transferring the web to a coarse fabric; (e) deflecting the web to substantially conform the web to the contour of the coarse fabric; (f) transferring the web to a transfer fabric; (g) transferring the web to the surface of a Yankee dryer and drying the web to final dryness; and (h) creping the web.
In still another aspect, the invention resides in a method for making a tissue product comprising: (a) depositing an aqueous suspension of papermaking fibers onto an endless forming fabric to form a wet web; (b) transferring the wet web to a papermaking felt; (c) pressing the web against the surface of a Yankee dryer and transferring the web thereto; (d) partially drying the web to a consistency of from about 40 to about 70 percent; (e) transferring the partially dried web to a coarse fabric; (f) deflecting the web to substantially conform the web to the contour of the coarse fabric; (g) transferring the web to a second Yankee dryer and final drying the web; and (h) creping the web.
In a further aspect, the invention resides in a method for making a throughdried tissue product comprising: (a) depositing an aqueous suspension of papermaking fibers onto an endless forming fabric to form a wet web; (b) transferring the wet web to a throughdryer fabric and partially drying the web in a first throughdryer to a consistency of from about 28 to about 45 percent; (c) sandwiching the partially-dried web between the throughdryer fabric and a coarse fabric; (d) deflecting the web to substantially conform the web to the contour of the coarse fabric; (e) carrying the web on the throughdryer fabric over a second throughdryer to dry the web to a consistency of about 85 percent or greater; (f) transferring the throughdried web to a Yankee dryer; and (g) creping the web.
In yet a further aspect, the invention resides in a method for making a throughdried tissue product comprising: (a) depositing an aqueous suspension of papermaking fibers onto an endless forming fabric to form a wet web; (b) transferring the wet web to a throughdrying fabric; (c) carrying the web over a first throughdryer and partially drying the web to a consistency of from about 28 to about 45 percent; (d) transferring the partially dried web to a second throughdrying fabric; (e) sandwiching the partially dried web between the second throughdrying fabric and a coarse fabric; (f) deflecting the web to substantially conform the web to the contour of the coarse fabric; (g) carrying the web over a second throughdryer to dry the web to a consistency of about 85 percent or greater; (h) transferring the web to a Yankee dryer; and (i) creping the web.
In another aspect the invention resides in a method for making a tissue product comprising: (a) depositing an aqueous suspension of papermaking fibers onto an endless forming fabric to form a wet web; (b) transferring the web to a papermaking felt; (c) compressing the web in a pressure nip to partially dewater the web and transferring the web to a Yankee dryer; (d) partially drying the web on the Yankee dryer to a consistency of from about 40 to about 70 percent; (e) transferring the partially dried web to a coarse mesh fabric; (f) deflecting the web to substantially conform the web to the contour of the coarse fabric; and (g) throughdrying the web.
In all aspects of the invention, the web can be creped, wet or dry, one or more times if desired. Wet creping can be an advantageous means for removing the wet web from the Yankee dryer.
The nature of the coarse fabric is such that the wet web must be supported in some areas and unsupported in others in order to enable the web to flex in response to the differential air pressure or other deflection force applied to the web. Such fabrics suitable for purposes of this invention include, without limitation, those papermaking fabrics which exhibit significant open area or three dimensional surface contour or depressions sufficient to impart substantial z-directional deflection of the web. Such fabrics include single-layer, multi-layer, or composite permeable structures. Preferred fabrics have at least some of the following characteristics: (1) On the side of the molding fabric that is in contact with the wet web (the top side), the number of machine direction (MD) strands per inch (mesh) is from 10 to 200 and the number of cross-machine direction (CD) strands per inch (count) is also from 10 to 200. The strand diameter is typically smaller than 0.050 inch; (2) On the top side, the distance between the highest point of the MD knuckle and the highest point of the CD knuckle is from about 0.001 to about 0.02 or 0.03 inch. In between these two levels, there can be knuckles formed either by MD or CD strands that give the topography a 3-dimensional hill/valley appearance which is imparted to the sheet during the wet molding step; (3) On the top side, the length of the MD knuckles is equal to or longer than the length of the CD knuckles; (4) If the fabric is made in a multi-layer construction, it is preferred that the bottom layer is of a finer mesh than the top layer so as to control the depth of web penetration and to maximize fiber retention; and (5) The fabric may be made to show certain geometric patterns that are pleasing to the eye, which typically repeat between every 2 to 50 warp yarns. Suitable commercially available coarse fabrics include a number of fabrics made by Asten Forming Fabrics, Inc., including without limitation Asten 934, 920, 52B, and Velostar V800.
The consistency of the wet web when the differential pressure is applied must be high enough that the web has some integrity and that a significant number of bonds have been formed within the web, yet not so high as to make the web unresponsive to the differential air pressure. At consistencies approaching complete dryness, for example, it is difficult to draw sufficient vacuum on the web because of its porosity and lack of moisture. Preferably, the consistency of the web will be from about 30 to about 80 percent, more preferably from about 40 to about 70 percent, and still more preferably from about 45 to about 60 percent. A consistency of about 50 percent is most preferred for most furnishes and fabrics.
The means for deflecting the wet web to create the increase in internal bulk can be pneumatic means, such as positive and/or negative air pressure, or mechanical means, such as a male engraved roll having protrusions which match up with the depressions or openings in the coarse fabric. Deflection of the web is preferably achieved by differential air pressure, which can be applied by drawing a vacuum from beneath the supporting coarse fabric to pull the web into the coarse fabric, or by applying positive pressure downwardly onto the web to push the web into the coarse fabric, or by a combination of vacuum and positive pressure. A vacuum suction box is a preferred vacuum source because of its common use in papermaking processes. However, air knives or air presses can also be used to supply positive pressure if vacuum cannot provide enough of a pressure differential to create the desired effect. When using a vacuum suction box, the width of the vacuum slot can be from approximately 1/16" to whatever size is desired, as long as sufficient pump capacity exists to establish sufficient vacuum. In common practice vacuum slot widths from 1/8" to 1/2" are most practical.
The magnitude of the pressure differential and the duration of the exposure of the web to the pressure differential can be optimized depending upon the composition of the furnish, the basis weight of the web, the moisture content of the web, the design of the supporting coarse fabric, and the speed of the machine. Without being held to any theory, it is believed that the sudden deflection of the web, followed by the immediate release of the pressure or vacuum, causes the web to flex down and up and thereby partially debond and hence expand. Suitable vacuum levels can be from about 10 inches of mercury to about 28 inches of mercury, preferably about 15 to about 25 inches of mercury, and most preferably about 20 inches of mercury. Such levels are higher than would ordinarily be used for mere transfer of a web from one fabric to another.
The number of times the wet web can be transferred to a coarse fabric and subjected to a pressure differential can be one, two, three, four or more times. To effect a more uniform bulking of the web, it is preferred that the wet straining vacuum be applied to both sides of the web. This can be conveniently accomplished simply by transferring the web from one fabric to another, in which the web is inherently supported on a different side after each transfer.
The method of this invention can preferably be applied to any tissue web, which includes webs for making facial tissue, bath tissue, paper towels, dinner napkins, and the like. Suitable basis weights for such tissue webs can be from about 5 to about 40 pounds per 2880 square feet. The webs can be layered or unlayered (blended). The fibers making up the web can be any fibers suitable for papermaking. For most papermaking fabrics, however, hardwood fibers are especially suitable for this process, as their relatively short length maximizes debonding rather than molding during the wet-straining operation. The wet-straining process can be used for either layered or homogeneous webs.
In carrying out the method of this invention, the change in Debonded Void Thickness of the web when subjected to the wet-straining step can be about 5 percent or greater, more preferably about 10 percent or greater, and suitably from about 15 to about 75 percent.
BRIEF DESCRIPTION OF THE DRAWING
FIGS. 1A and 1B are cross-sectional photographs of a conventional wet-pressed tissue web and a tissue web processed in accordance with this invention, respectively, illustrating the increase in internal bulk resulting from the method of this invention.
FIGS. 2-7 are schematic flow diagrams of different aspects of the method of this invention referred to above.
FIGS. 8-13 pertain to the method of determining the Debonded Void Thickness of a sample.
FIG. 14 is a schematic illustration of the apparatus used to wet strain handsheets in the Examples.
FIG. 15 is a plot of the Debonded Void Thickness as a function of consistency, illustrating the data as described in Example 2.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the Drawing, the invention will be described in greater detail. Wherever possible, the same reference numerals are used in the various Figures to identify the same apparatus for consistency and simplicity. In all of the embodiments illustrated, conventional papermaking apparatus and operations can be used with respect to the headbox, forming fabrics, dewatering, transferring the web from one fabric to another, drying and creping, all of which will be readily understood by those skilled in the papermaking art. Nevertheless, these conventional aspects of the invention are illustrated for purposes of providing the context in which the various wet-straining embodiments of this invention can be used.
FIGS. 1A and 1B are 150× photomicrographs of handsheets of nominally equal basis weight. The handsheet of FIG. 1A (Sample 1A) was wet-pressed, while the handsheet of FIG. 1G (Sample 1B) was wet-pressed and thereafter wet-strained in accordance with this invention. Both handsheets were made from 50/50 blends of spruce and eucalyptus dispersed in a British Pulp Disintegrator for 5 minutes. Both sheets were then pressed between blotters in an Allis-Chalmers Valley Laboratory Equipment press for 10-15 seconds at 90-95 pounds per square inch gauge (psig) pressure. Sheet consistencies were 56±3 percent. Sample 1A was then dried while sample 1B was wet-strained as described herein and then dried. As the photos illustrate, the wet-straining reduced the density of the sheet yielding a significantly higher caliper. Sample 1A is typical of the structure of wet-pressed sheets while Sample 1B has a more debonded structure having greater internal bulk, similar to a throughdried sheet. The Debonded Void Thickness of Sheet 1A was 31.5 microns compared to 38.9 microns for Sheet 1B. Normalizing using basis weight led to Normalized Debonded Void Thickness values of 138.2 microns per gram and 169.9 microns per gram, respectively. The 23 percent increase in Normalized Debonded Void Thickness with only a 14 percent reduction in tensile strength (from 1195 grams per inch of sample width to 1029 grams) illustrates the improvement provided by wet-straining.
FIG. 2 illustrates a combination throughdried/wet-pressed method of making creped tissue in accordance with this invention. Shown is a headbox 1 which deposits an aqueous suspension of papermaking fibers onto an endless forming fabric 2 through which some of the water is drained from the fibers. The resulting wet web 3 retained on the surface of the forming fabric has a consistency of about 10 percent. The wet web is transferred to a papermaking felt 4 and further dewatered in a press nip 5 formed between felt 4 and a second felt 4'. The press nip further dewaters the wet web to a consistency of about 30 percent or greater. The dewatered web 6 is then transferred to a coarse mesh throughdrying fabric 7 and wet-strained with vacuum source 8 positioned underneath the throughdrying fabric to abruptly deflect some of the fibers in the web into the open areas or depressions in the throughdrying fabric and thereby partially debond the web and increase its caliper or thickness. Also shown is an optional wet-straining station comprising a coarse mesh fabric 9 and a vacuum source 8', which can be used in addition to the other wet straining operation or as a replacement therefor. Providing two wet-straining stations provides added flexibility in the use of two different coarse mesh fabrics, which can be utilized to wet-strain the web independent of the desired throughdrying fabric. The wet-straining stations can operate on the web simultaneously or in sequence. In addition, in all of the embodiments shown herein, the wet-straining vacuum sources can be assisted by providing a high pressure air source which directs an air stream onto the opposite side of the web, thereby providing a further increase in pressure differential across the coarse fabric and increasing the driving force to deflect fibers into the coarse fabric.
The wet-strained web 10 is then carried over the throughdrying cylinder 11 and preferably dried to a consistency of from about 85 percent to about 95 percent. The dried web 12 is then transferred to an optional transfer fabric 13, which can be either fine or coarse, which is used to press the web against the surface of the Yankee dryer 14 with pressure roll 15 to adhere the web to the Yankee surface. The web is then completely dried, if further drying is necessary, and dislodged from the Yankee with a doctor blade to produce a creped tissue 16.
FIG. 3 illustrates a wet-press method of this invention in which a throughdryer is not used. Shown is a headbox 1 which deposits an aqueous suspension of papermaking fibers onto a forming fabric 2 to form a wet web having a consistency of about 10 percent. The wet web is transferred to a papermaking felt 4 and further dewatered in a press nip 5 formed between felt 4 and a second felt 4'. The dewatered web 6 is then transferred to a coarse mesh fabric 31 and wet-strained using vacuum source 8 before transferring to fabric 32. Optionally, a vacuum source 8' can be utilized in addition to vacuum source 8 or in place of vacuum source 8. If used in addition to vacuum source 8, additional wet-straining can be achieved. If the coarseness of fabric 32 is different than that of fabric 31 or if the mesh openings of the two fabrics do not coincide, areas of the web not strained by the first vacuum source can be strained by the second vacuum source. In any event, the second vacuum source acts upon the opposite side of the web to achieve additional straining and debonding of the web. Wet-straining from both sides of the web can be particularly advantageous if layered webs are present, especially if the outer layers are more susceptible to debonding than the inner layer(s). As previously mentioned, a predominance of hardwood fibers in the outer layer lends itself well to wet-straining. The wet-strained web 33 is then transferred to the surface of Yankee dryer 14 using pressure roll 15 and dislodged by doctor blade (creped), resulting in creped tissue 34.
FIG. 4 illustrates a method of this invention utilizing two dryers in series with wet-straining in between. Shown is a headbox 1 which deposits the aqueous suspension of papermaking fibers onto a forming fabric 2 to form a wet web 3 having a consistency of about 10 percent. The wet web is transferred to a papermaking felt 4 and further dewatered and pressed onto the surface of Yankee dryer 14 using pressure roll 15. The consistency of the web after transfer to the surface of the Yankee is preferably about 40 percent. (The Yankee can optionally be replaced by a throughdryer, which would require transfer of the web from the felt 4 to a throughdryer fabric or replacement of the felt with a throughdryer fabric, not shown.) The Yankee (or the throughdryer) serves to partially dry the dewatered web to a consistency of preferably from about 50 to about 70 percent. The partially-dried web is then transferred to a coarse mesh fabric 41 with the assistance of vacuum suction roll 42 and wet-strained using vacuum source 8. Optionally, the web can be sandwiched between fabric 41 and another coarse fabric 41" and further wet-strained using a second vacuum source 8". The second vacuum source can be applied to the web simultaneously with vacuum source 8 to simultaneously act upon both sides of the web, or the second vacuum source can be applied upstream or downstream of the first vacuum source to sequentially act upon opposite sides of the web. In any event, the application of two or more vacuum straining sources is expected to provide more uniform debonding of the web. After wet-straining, the web is transferred to a Yankee dryer 14' for final drying and creped to yield a creped tissue web.
FIG. 5 illustrates another embodiment of this invention in which two throughdryers are used to dry the web. Shown is the headbox 1 which deposits the aqueous suspension of papermaking fibers onto the surface of forming fabric 2. The wet web 3 is transferred to an optional fine mesh transfer fabric 51 and thereafter transferred to a coarse mesh throughdryer fabric 7. The web is then partially dried in the first throughdryer 11 to a consistency of preferably about 45 percent. The partially dried web is then sandwiched between the throughdryer fabric 7 and coarse mesh fabric 52 and wet-strained using vacuum source 8. (For purposes herein, bringing a web into contact with a coarse mesh fabric, such as sandwiching the web against the coarse mesh fabric 52, is considered "transferring" the web to the coarse mesh fabric, even though the web continues to travel with a different fabric, such as the throughdryer fabric in this case.) Optionally, the web can be simultaneously or subsequently wet-strained from the opposite direction on the throughdryer fabric to further debond the web.
After wet-straining, the web is carried over a second throughdryer 11' and further dried to a consistency of preferably about 85 to about 95 percent, transferred to a fine mesh fabric 53, and pressed onto the surface of a Yankee dryer 14 for final drying, if necessary, and creping to produce creped web 27. In the case of final drying on the second throughdryer, transfer to the Yankee for creping is an option. It is within the scope of this invention that whenever a throughdryer is used to dry the web, the final product can be uncreped.
FIG. 6 illustrates a similar process to that of FIG. 5, but using two throughdrying fabrics. Shown is the headbox 1 depositing the aqueous suspension of papermaking fibers onto the surface of the forming fabric 2. The web 3 is transferred to optional fine mesh fabric 51 and thereafter transferred to throughdrying fabric 7. The web is carried over the first throughdryer 11 and partially dried to a consistency of preferably about 45 percent. The partially dried web is then transferred to a second throughdryer fabric 7' and sandwiched between the second throughdryer fabric and coarse fabric 61. Vacuum source 8 is used to wet-strain and partially debond the web as previously described. Optionally, the web can be wet-strained from the opposite direction using alternative vacuum source 8', either in addition to or in place of vacuum source 8. The web is then further dried in a second throughdryer 11', transferred to a Yankee 14 and creped. Optionally, the web can be wet-strained using optional vacuum sources 8" and 8'". If vacuum source 8" is used, a coarse fabric 62 is used to provide the depressions into which the fibers in the web are deflected.
FIG. 7 illustrates another embodiment of this invention, similar to that illustrated in FIG. 4, but using a throughdryer 11 to final dry the web.
FIGS. 8-14 pertain to the method for determining the Debonded Void Thickness, which is described in detail below. Briefly, FIG. 8 illustrates a plan view of a specimen sandwich 80 consisting of three tissue specimens 81 sandwiched between two transparent tapes 82. Also shown is a razor cut 83 which is parallel to the machine direction of the specimen, and two scissors cuts 84 and 85 which are perpendicular to the machine direction cut.
FIG. 9 illustrates a metal stub which has been prepared for sputter coating. Shown is the metal stub 90, a two-sided tape 91, a short carbon rod 92, five long carbon rods 93, and four specimens 94 standing on edge.
FIG. 10 shows a typical electron cross-sectional photograph of a sputter coated tissue sheet using Polaroid® 54 film.
FIG. 11A shows a cross-sectional photograph of the same tissue sheet as shown in FIG. 10, but using Polaroid 51 film. Note the greater black and white contrast between the spaces and the fibers.
FIG. 11B is the same photograph as that of FIG. 11A, except the extraneous fiber portions not connected or in the plane of the cross-section have been blacked out in preparation for image analysis as described herein.
FIG. 12 shows two Scanning Electron Micrograph (SEM) specimen photographs 100 and 101 (approximately 1/2 scale), illustrating how the photographs are trimmed to assemble a montage in preparation for image analysis. Shown are the photo images 102 and 103, the white border or framing 104 and 105, and the cutting lines 106 and 107.
FIG. 13 shows a montage of six photographs (approximately 1/2 scale) in which the white borders of the photographs are covered by four strips of black construction paper 108.
FIG. 14 is a schematic illustration of the apparatus used to wet strain sample handsheets as described in the Examples. Shown is a sample holder 110 which contains an Asten 934 throughdrying fabric. The sample holder is designed to accept a similarly sized handsheet mold in which the handsheet sample is formed and supported by a suitable forming fabric. Also shown is a vacuum tank 111, a slideable rod 112 connected to a slideable "sled" 113 having a 1/4 inch (0.63 centimeters) wide slot 114 through which vacuum is applied to the sample, a pneumatic cylinder 115 for propelling the sled underneath the sample, and a shock absorber 116 for receiving and stopping the rod. In operation, the vacuum tank is evacuated as indicated by arrow 117 to the desired vacuum level via a suitable vacuum pump. The handsheet, while still in the handsheet mold and having one side is still in contact with the forming fabric of the handsheet mold and at the desired consistency, is placed "upside down" in the sample holder of the illustrated apparatus such that the other side of the handsheet is in contact with the throughdryer fabric of the sample holder. The pneumatic cylinder is then pressurized with nitrogen gas to cause the rod 112 and the connected sled 113 to move at a controlled speed toward the shock absorber at the end of the apparatus. In so doing, the slot in the sled briefly passes under the sample holder as shown and thereby briefly subjects the sample to the vacuum, thereby mimicking a continuous process in which the tissue is moving and the vacuum slot is fixed. The brief exposure to vacuum wet strains the sample as it is transferred to the throughdrying fabric in the sample holder. The handsheet is then dried to final dryness while supported by the throughdrying fabric by any suitable noncompressive means such as throughdrying or air drying. In all of the examples described herein, the speed of the sled was 2000 feet per minute (10.1 meters per second) and the level of vacuum was 25 inches of mercury.
Debonded Void Thickness
The method for determining the Debonded Void Thickness (DVT) is described below in numerical stepwise sequence, referring to FIGS. 8-13 from time to time. In general, the method involves taking several representative cross-sections of a tissue sample, photographing the fiber network of the cross-sections with a scanning electron microscope (SEM), and quantifying the spaces between fibers in the plane of the cross-section by image analysis. The total area of spaces between fibers divided by the frame width is the DVT for the sample.
A. Specimen Sandwiches
1. Samples should be chosen randomly from available material. If the material is multi-ply, only a single ply is tested. Samples should be selected from the same ply position. The same surface is designated as the upper surface and samples are stacked with the same surface upwards. Samples should be kept at 30° C. and 50 percent relative humidity throughout testing.
2. Determine the machine direction of the sample, if it has one. The cross-machine direction of the sample is not tested. The cross-section will be cut such that the cut edge to be analyzed is parallel to the machine direction. For strained handsheets the cut is made perpendicular to the wire knuckle pattern.
3. Place about five inches (127 millimeters) of tape (such as 3M Scotch™ Transparent Tape 600 UPC 021200-06943), 3/4 inch (19.05 millimeters) width, on a working surface such that the adhesive side is uppermost. (The tape type should not shatter in liquid nitrogen).
4. Cut three 5/8 inch (or 15.87 millimeters) wide by about 2" (or 50.8 millimeters) long specimens from the sample such that the long dimension is parallel to the machine direction.
5. Place the specimens on the tape in an aligned stack such that the borders of the specimens are within the tape borders (see FIG. 8). Specimens which adhere to the tape will not be usable.
6. Place another length of tape of about 5 inches (or 127 millimeters) on top of the stack of specimens with the adhesive side towards the specimens and parallel to the first tape.
7. Mark on the upper surface of the tape which is the upper surface of the specimen.
8. Make twelve specimen sandwiches. One photo will be taken for each specimen.
B. Liquid Nitrogen Sample Cutting
Liquid nitrogen is used to freeze the specimens. Liquid nitrogen is dispensed into a container which holds the liquid nitrogen and allows the specimen sandwich to be cut with a razor blade while submerged. A VISE GRIP™ pliers can hold the razor blade while long tongs secure and hold the specimen sandwich. The container is a shallow rigid foam box with a metal plate in the bottom for use as a cutting surface.
1. Place the specimen sandwich in a container which has enough liquid nitrogen to cover the specimen. Also place the razor blade in the container to adjust to temperature before cutting. A new razor blade must be used for each sandwich to be cut.
2. Grip the razor blade with the pliers and align the cutting edge length with the length of the specimen such that the razor blade will make a cut that is parallel with the machine direction. The cut is made in the middle of the specimen. (See FIG. 8).
3. The razor blade must be held perpendicular to the surface of the specimen sandwich. The razor blade should be pushed downward completely through the specimen sandwich so that all layers are cleanly cut.
4. Remove the specimen sandwich from the liquid nitrogen.
C. Metal Stub Preparation
1. The metal stubs' dimensions are dictated by the parameters of the SEM. The dimensions as illustrated in FIG. 9 are about 22.75 millimeters in diameter and about 9.3 millimeters thick.
2. Label back/bottom of stub with the specimen name.
3. Place a length of two-sided tape (3M Scotch™ Double-Coated Tape, Linerless 665, 1/2 inch or about 12.7 millimeters!wide) across the diameter of the stub. (See FIG. 9).
4. Place about a 1/4" (or about 6.35 millimeters) length of 1/8 inch (or about 3.17 millimeters) diameter carbon rod (manufacturer: Ted Pella, Inc., Redding, Calif., 1/8 or 3.17 millimeters! diameter by 12-inch or 304.8 millimeters! length, Cat. #61-12) at one end of the tape within the edges of the stub such that its length is perpendicular to the length of the tape. This marks the top of the stub and the upper surface of the specimen.
5. Place a longer rod below the short rod. The length of the rod should not extend beyond the edge of the stub and should be approximately the length of the specimen.
6. Cut the specimen sandwich perpendicular to the razor cut at the ends of the razor cut (see FIG. 8).
7. Remove the inner specimen and place standing up next to (and touching) the carbon rod such that its length is parallel to the rod's length and its razor cut edge is uppermost. The upper surface of the specimen should face the small carbon rod.
8. Place another carbon rod approximately the length of the specimen next to the specimen such that it is touching the specimen. Again, the rod should not extend beyond the disk edges.
9. Repeat specimen, rod, specimen, rod until the metal stub is filled with four specimens. Three stubs will be used for the procedure.
D. Sputter Coating the Specimen
1. The specimen is sputter coated with gold (Balzar's Union Model SCD 040 was used). The exact method will depend on the sputter coater used.
2. Place the sample mounted on the stub in the center of the sputter coater such that the height of the sample edge is about in the middle of the vacuum chamber, which is about 11/4 inches (or 31.75 millimeters) from the metal disk.
3. The vacuum chamber arm is lowered.
4. Turn the water on.
5. Open the argon cylinder valve.
6. Turn the sputter coater on.
7. Press the SPUTTERING button twice. Set the time using SET and FAST buttons. Three minutes will allow the specimen to be coated without over-coating (which could cause a false thickness) or under coating (which could cause flaring).
8. Press the STOP button once so it is flashing. Press the TENSION button at this time. The reading should be 15-20 volts. Hold the TENSION button down and press CURRENT UP and hold. After about a ten-second delay, the reading will increase. Set to approximately 170-190 volts. The current will not increase unless the STOP button is flashing.
9. Release the TENSION and CURRENT UP buttons as you turn the switch on the arm to the green dot to open the window. The current should read about 30 to 40 milliamps.
10. Press the START button.
11. When completed, close the window on the arm and turn the unit off. Turn off the water and argon. Allow the unit to vent before the specimen is removed.
E. Photographing with the SEM
(JEOL, JSM 840 II, distributed by Japanese Electro Optical Laboratories, Inc. located in Boston, Mass.). A clear, sharp image is needed. Several variables known to those skilled in the art of microscopy must be properly adjusted to produce such an image. These variables include voltage, probe current, F-stop, working distance, magnification, focus and BSE Image wave form. The BSE wave form must be adjusted up to and slightly beyond the reference limit lines in order to obtain proper black-&-white contrast in the image.
These variables are adjusted to their optimum to produce the clear, sharp image necessary and individual adjustments are dependent upon the particular SEM being used. The SEM should have a thermatic source (tungsten or Lab 6) which allows large beam current and stable emission. SEMs which use field emission or which do not have a solid state back scatter detector are not suitable.
1. Load the stub such that the specimen's length is perpendicular to the tilt direction and lowered as far as possible into the holder so that the edge is just above the holder. Scan rotation may be necessary depending on the SEM used.
2. Adjust the working distance (39 millimeters was used). The specimen should fill about 1/3 of the photo area, not including the mask area. (For handsheets, a magnification of 150× was used.)
3. Use the tilt angle of the SEM unit to show the very edge of the specimen with as little background fibers as possible. Do not select areas that have long fibers that extend past the frame of the photo.
4. One photomicrograph is taken using normal film (POLAROID 54) for gray levels for comparison. The F-stop may vary. The areas selected should be representative and not include long fibers that extend beyond the vertical edge of the viewing field.
5. Without moving the view, take one photomicrograph using back scatter electrons with high contrast film (51 Polaroid). The F-stop may vary. A sharp, clear image is needed. After the photomicrographs are developed, a black permanent marker is used to black out background fibers that are out of focus and are not on the edge of the specimen. These can be selected by comparing the photomicrograph to the gray level photomicrograph of Step 4 above. (See FIGS. 10 and 11.)
6. A total of twelve photomicrographs are taken to represent different areas of the specimens; one photomicrograph is taken of each specimen.
7. A protective coating is applied to the photo on 51 film.
F. Image Analysis of SEM Photos
1. The 12 photos are arranged into two montages. Six photos are used in each montage. Make two stacks of six photos each, and cut the white framing off the left side of one and the white framing off the right side of the remaining stack without disturbing the photos. (See FIG. 12.)
2. Then, taking one photo from each stack, place cut edges together and tape together with the tape on the back of the photo (3M Highland™ Tape, 3/4 inch or 19.05 millimeters!). No extraneous white of the background should show at the cut, butted edges.
3. Arrange the photos with a small overlap from top to bottom as in FIG. 13.
4. Turn on the image analyzer (Quantimet 970, Cambridge Instruments, Deerfield, Ill.). Use a 50 mm. El-Nikkor lens with C-mount adaptor (Nikon, Garden City, New York) on the camera and a working distance of about 12 inches (305 millimeters). The working distance will vary to obtain a sharp clear image on the monitor and the photo. Make sure the printer is on line.
5. Load the program (described below).
6. Calibrate the system for the photo magnification (which will generate the calibration values indicated by "x.xxxx" in the program listed below), set shading correction with white photo surface (undeveloped x-ray film), and initialize stage (12 inches by 12 inches open frame motor-driven stage (auto stage by Design Components, Inc., Franklin, Massachusetts)) with step size of 25 microns per step.
7. Load one of the two photo montages under a glass plate supported on the stage after strips of black construction paper are placed over the white edges of the photos. The strips are 3/4 inch wide (18.9 millimeter) and 11 inches long (279 millimeters) and are placed as in FIG. 13 so that they do not cover the image in the photo. The montage is illuminated with four 150 watt, 120 volt GE reflector flood lamps positioned with two lamps positioned at an angle of about 30° on each side of the montage at a distance of about 21 inches (533 millimeters) from the focus point on the montage.
8. Adjust the white level to 1.0 and the sensitivity to about 3.0 (between 2 and 4) for the scanner using a variable voltage transformer on the flood lamps.
9. Run the program. The program selects twelve fields of view: two per photomicrograph.
10. Repeat at the pause with the second montage after completion of twelve fields of view on the first montage.
11. A printout will give the Debonded Void Thickness.
G. Computer Program
__________________________________________________________________________ Enter specimen identityScanner (No. 2 Chalnicon LV = 0.00 SENS = 1.64 PAUSE)Load Shading Corrector (pattern - OFOSU3)Calibrate User Specified (Calibration Value = x.xxxx microns per pixel) (PAUSE)CALL STANDARDTOTDEBARE : = 0.For SAMPLE = 1 to 2Stage Scan ( X Y scan origin 10000.0 10000.0 field size 16500.0 11000.0 no. of fields 3 4 )Detect 2D (Lighter than 32 PAUSE)For FIELDScanner (No. 2 Chalnicon AUTO-SENSITIVITY LV = 0.00)Live Frame is Standard Live FrameDetect 2D (Lighter than 32)Amend (OPEN by 1)Measure field - Parameters into array FIELDRAWAREA: = FIELD AREAAmend (CLOSE by 20)Image Transfer from Binary B (FILL HOLES) to Binary OutputMeasure field - Parameters into array FIELDFILLAREA: = FIELD AREADEBNAREA: = FILLAREA - RAWAREATOTDEBARE: = TOTDEBARE + DEBNAREAStage StepNext FIELDPauseNextFIELDNUM: = FIELDNUM * (SAMPLE - 1.)Print " "Print "DEBOND VOID THICKNESS =", ( TOTDEBARE / FIELDNUM)/(625.* CAL.CONSTPrint " "For LOOPCOUNT = 1 to 7Print " "NextEnd of Program__________________________________________________________________________
EXAMPLES
In order to further illustrate the invention, a number of handsheets were prepared as follows:
The pulp was dispersed for five minutes in a British pulp disintegrator. Circular handsheets of four-inch diameter, conforming precisely to the dimensions of the sample holder used for wet-straining, were produced by standard techniques. The sample holder contained a 94-mesh forming fabric on which the handsheets were formed. After formation the handsheets were at about 5 percent consistency. For those samples not wet-pressed (Example 1), the samples were dried to the consistency selected for wet-straining by means of a hot lamp and then wet-strained. For those experiments involving pressing (Example 2), the handsheet was removed from the sample holder by couching with a dry blotter. The sheet was then pressed in an Allis-Chalmers Valley Laboratory Equipment press. Pressing time and/or pressure were varied to achieve the desired post-pressing consistency. Selected samples were then wet-strained.
Wet-straining of the handsheets was performed using the apparatus previously described in reference to FIG. 14. In all cases, a sample holder containing an Asten 934 throughdrying fabric was placed in the wet-straining apparatus. When the base sheet reached the desired consistency, either by pressing or drying with the lamp, the holder on which the sheet was formed was placed "upside down" in the straining apparatus such that the surface of the sheet not in contact with the forming fabric came in contact with the surface of the throughdrying fabric. A sled was then caused to slide underneath the sample holders exposing the sheet to vacuum, causing the sheet to be wet-strained and transferred to the throughdrying fabric. In all cases, a sled speed of 2000 fpm and a vacuum of 25 inches of mercury were utilized. The sheet, now located on the throughdrying fabric, was then dried to complete dryness in a noncompressive manner.
Example 1
Handsheets were made from a 100 percent eucalyptus furnish and dried with a hot lamp to various consistencies prior to wet-straining as described above. After wet-straining, various physical parameters were measured as shown in TABLE 1 below. (Sample weight is expressed in grams; Consistency is expressed in weight percent; Tensile strength is expressed as grams per inch of sample width; Normalized tensile strength is the tensile strength divided by the sample weight, expressed as reciprocal inches; Debonded Void Thickness is expressed as microns; and Normalized Debonded Void Thickness is the Debonded Void Thickness divided by the sample weight, expressed as microns per gram.)
TABLE 1__________________________________________________________________________ NormalizedConsistency Debonded DebondedSamplePrior to Normalized Void VoidWeightWet Straining Tensile Tensile Thickness Thickness__________________________________________________________________________0.30513.2 420 1377 86.1 282.30.23533.6 396 1685 84.1 357.90.22746.3 255 1123 82.6 363.9__________________________________________________________________________
For comparison, an air-dried control sample (not wet-strained) weighing 0.238 grams had a tensile strength of 460 grams, a normalized tensile of 1933, a Debonded Void Thickness of 73 microns, and a Normalized Debonded Void Thickness of 306.7 microns per gram.
These results clearly show that wet-straining can be used to increase the void area relative to the weight of the sheet. As the data indicates, conducting the wet-straining at only 13 percent consistency (below the level claimed in this application) did not result in a significant increase in Normalized Debonded Void Thickness. Instead the sheet was primarily molded to the shape of the fabric. However, for the samples wet-strained at higher consistency, a definite increase in the Normalized Debonded Void Thickness was apparent and the tensile strength (a measure of bonding in the sheet) significantly decreased. Hence wet straining becomes effective at approximately 30 percent consistency or greater, with an optimum wet-straining consistency varying with furnish, fabric, etc. However, the optimum consistency is believed to lie in the 40-50 percent range.
Example 2
Handsheets nominally weighing 0.235±0.200 grams were made from a 50/50 blend by weight of eucalyptus and spruce fibers. One set of handsheets was pressed to various consistencies (not wet strained) to serve as a control. Another set was pressed to approximately 50 percent consistency and then wet strained as described above. Consistencies, sample weights and the Debonded Void Areas were measured for each sample. The data is tabulated in TABLE 2 below and further illustrated in FIG. 15. The first six samples listed represent the control samples. The last five samples are the wet-strained samples.
TABLE 2__________________________________________________________________________ Normalized Post Debonded DebondedSample Pressing Normalized Void VoidWeight Consistency Tensile Tensile Thickness Thickness__________________________________________________________________________0.252 30.7 662 2627 73.2 290.50.224 31 760 3393 56.5 252.20.237 34.9 684 2886 72.6 306.30.241 35 761 3158 59.1 245.20.228 58.5 1195 5241 31.5 138.20.229 60.3 1207 5271 29 126.60.224 51.3 774 3455 58.6 261.60.246 51.5 887 3606 64.2 2610.23 52.6 848 3687 63.1 274.30.229 54.3 1029 4493 38.9 169.90.241 58.9 826 3427 55.2 229AVERAGE 53.72 239.2__________________________________________________________________________
As shown in FIG. 15, the line in this figure is a regression line for the control data according to the equation: Normalized Debonded Void Thickness=444.5-(5.22×Consistency). As expected, the Normalized Debonded Void Thickness linearly decreased with pressing. While pressing is an effective means for removing water, it causes densification that reduces the Normalized Debonded Void Thickness and makes the resulting sheet less bulky and absorbent.
Also shown in FIG. 15 are the data points for the five wet straining samples and the arithmetic average for the five samples. The average Normalized Debonded Void Thickness of 239.2 at an average consistency of 53.7 percent was 46 percent higher than the predicted value of 163.8 at 53.7 percent consistency from the regression equation. This increase in Normalized Debonded Void Thickness is the desired result of the wet straining operation.
Hence it is clear that wet straining can be used to significantly increase the Debonded Void Thickness of paper. The benefits of this process can be manifested as higher Debonded Void Thickness at a given level of pressing or as the ability to press to a higher consistency while maintaining a given level of Debonded Void Thickness. Which approach is best depends on the amount of bulk and absorbency desired for a given product and the limitations of the particular papermaking process being utilized. In either case, an improved product can be produced via wet straining in accordance with this invention.
It will be appreciated that the foregoing examples, given for purposes of illustration, are not to be construed as limiting the scope of this invention, which is defined by the following claims and all equivalents thereto. | The internal bulk of a tissue web can be improved during manufacturing of the basesheet by subjecting the tissue web to differential pressure while supported on a coarse fabric at a consistency of about 30 percent or greater. The differential pressure, such as by applying vacuum suction to the underside of the coarse fabric, causes the wet web to deflect into the openings or depressions in the fabric and "pop" back, resulting in a substantial gain in thickness or internal bulk. The method is especially adapted to improve the internal bulk of wet-pressed tissue webs. | 3 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to apparatus for straight and directional drilling of underground formations. More particularly, the invention relates to drill bits for earth-boring drill strings for navigational drilling.
2. State of the Art
The ability to steer a drill string in a preferred direction in earth formations has been developing for several decades. At least two technologies are required.
First, the drilling crew must be able to navigate. That is, the crew must be able to tell where a drill bit at the bottom of the drill string is located in terms of direction, rotational orientation and distance. In recent decades, downhole navigational technology has greatly improved the ability to find the exact position and orientation of a tool at the bottom of a drill string.
The second requirement is the mechanical technology of downhole tools for orienting the bit at the end of the drill string to drill directionally at some angle away from a straight path.
In recent years, navigation technology and directional drilling technology have been employed in a new type of drilling in which a single drill string may be used in drilling both straight and non-linear segments of the bore hole without pulling or "tripping" the drill string for replacement of bottom hole assembly components. This new type of drilling, generally called "steerable drilling" or "navigational drilling," employs both a rotatable drill string and a downhole motor (generally a Moineau principle mud motor, although turbines have also been employed) for rotation of the drill bit independently from drill string rotation. Another key component for navigational drilling is a means for orienting or tilting the drill bit at a small angle (typically less than 4°) to the motor and drill string above. Navigational drilling is then effected with such a string by orienting the drill bit and drilling under motorpowered bit rotation alone for drilling a curve, and rotating the drill string in addition to driving the bit with the motor for drilling a straight bore hole. The first patents directed to this technique and various bottom hole assemblies for carrying it out are U.S. Pat. Nos. 4,465,147; 4,485,879 and 4,492,276.
U.S. Pat. No. 4,465,147 (Feenstra et al., 1984) discusses a method and means for controlling the course of a bore hole which uses a downhole motor having an eccentric stabilizer mounted on each end of the housing. This system uses the drill bit attached to the output shaft of the hydraulic motor offset in the bore hole to cant the hydraulic motor off the axis of the main drill string. The axis of rotation of the downhole motor attached to the drill bit and the drill bit itself precesses when the drill string rotates for straight drilling.
U.S. Pat. No. 4,485,879 (Kamp et al., 1984) discusses a method and means for controlling the course of a bore hole which uses a downhole motor having a housing having a preferential tendency to bend in a particular longitudinal plane. As with the '147 patent, the bottom hole assembly of the '879 patent will cause precession of the drill bit, perhaps to a lesser magnitude but with even greater lack of predictability due to the increased preferential bending elasticity of the motor housing.
U.S. Pat. No. 4,492,276 (Kamp, 1985) discloses a downhole drilling motor and method for directional drilling of bore holes which uses a tilted bearing unit to support and incline an output shaft relative to the axis of the motor housing. In this way, the central axis of the output shaft intersects the longitudinal axis of the motor housing rather than coinciding with it.
In addition to the foregoing patents, U.S. Pat. No. 4,667,751 (Geczy et al., 1987) discloses a system and method for controlled rotational drilling which employs a bent housing (tilt unit) attached to a drill string below a downhole motor. Stabilizers are used above and below the bent housing with a stationary drill string to set the direction of the drill bit for drilling a curved hole or a straight hole in the manner previously described. One notable deficiency with this system, as with other navigational drilling bottom hole assemblies, is the drilling of a hole which is oversized from the nominal size of the drill bit when both the hydraulic motor and the drill string are rotated.
U.S. Pat. No. 4,739,842 (Kruger et al., 1988) discusses an apparatus for optional straight or directional drilling of underground formations, which in some embodiments is virtually identical to that of the '751 patent. The '842 patent discusses a downhole motor having an output shaft connected to the drill bit either through a single tilted output shaft, or a shaft assembly having two opposite tilts to minimize the lateral offset of the drill bit from the drill string above. Either concentric or eccentric stabilizers may be employed.
With all navigational drilling bottom hole assemblies, a change in drilling direction and the act of non-linear drilling itself causes stresses in the bottom hole assembly which are transmitted to the drill bit, causing excessive friction between the drill bit and the wall of the bore hole.
As discussed in the '842 patent, when the drill string is not rotating, the bottom hole assembly with drill bit and stabilizers define points on a curve, the radius of which defines the angle of curvature drilled by the bottom hole assembly in a directional drilling mode. Upon rotation of the drill string, the bottom hole assembly rotates eccentrically in the bore hole. The drill bit, although drilling a hole which is axially aligned with the main drill string, drills an oversized hole. The axis of rotation of the bit rotating on the downhole hydraulic motor precesses around the axis of the straight bore hole.
As noted previously, the basic approach of navigational drilling is to have a drill string comprised of lengths of drill pipe threadedly connected and extending from a drilling rig into the earth formation. The drill string is attached to a rotary table or top drive on the drill rig. In the first case, the drill string itself is keyed to the rotary table so that it can axially move through the rotary table but must rotate with it. If a top drive is used, the drive is lowered as the drill string progresses. As a drill bit attached to the extreme distal end of the drill string cuts its way further into the earth formation, additional drill pipe is attached to the drill string and lowered into the bore or hole.
For purposes of lubrication of parts, sealing the bore, cooling the face of the bit, powering downhole motors, and for carrying away the debris from the earth formation being drilled, drilling mud is pumped down through the drill string. The drill pipe has a sufficient inside diameter for mud flow, discharging the mud through ports in the face of the drill bit crown. Ports in the drill bit face may aim numerous flows of mud toward the cutting elements in the bit crown. Passages for carrying the mud along the face of the bit crown are designed into the bit along with junk slots along the gage of the bit to pass the debris upward into the annulus formed by the drill string and the wall of the well bore. The drill pipe being of smaller diameter than the gage of the drill bit, the annulus formed between the drill string and the bore wall can accommodate the dense mud as it entrains and carries the debris upward to be removed at the surface before the mud is recycled down the well hole.
High pressures are required to pump drilling mud from the surface to the face of a drill bit at the bottom of several thousand feet of mud column. High flows to carry debris and to cool cutters mean extremely high horsepowers at these pressures. Tremendous energy is coursing through the flow of mud. In addition, the hydrostatic pressure at the bottom of the hole is several thousand pounds per square inch.
The high energy content of the high pressure mud flow permits the use of a second prime mover in addition to the engine rotating the drill string from the top of the well. A special hydraulic motor, which may comprise a turbine but which is generally a Moineau-principle type motor, is attached in the drill string to extract energy from the mud flow. The outer casing of the downhole hydraulic motor is engaged to rotate with the drill string while an output shaft extending downwardly from the hydraulic motor turns at some angular velocity with respect to the drill string. Thus, the output shaft from the hydraulic motor rotates at the angular velocity of the output shaft with respect to the drill string plus the angular velocity of the drill string rotating with respect to the earth formation.
The essential concept of navigational drilling employs a mechanism above or usually below the hydraulic motor in the drill string to cant or tilt the drill bit at a slight angle to the well bore axis, normally on the order of a fraction of a degree to four degrees. To drill in a direction away from the current path of the bore hole, the drilling crew rotates the drill string through an arc of less than 360° to orient the drill bit connected to the output shaft of the downhole hydraulic motor. If driven only by the hydraulic motor, the bit points in the desired direction of drilling. In that orientation, the drill string is not rotated; only the output shaft of the hydraulic motor is rotated. As the hydraulic motor output shaft rotates, the drill bit cuts, chips, grinds, or crushes the formation before it to form a bore hole path shaped in a long arc. That is, as the drill bit moves ahead, the canting or tilting mechanism which forces the bit to cut to one side on an angle from the drill string follows the bit into the hole, continuing to force the bit to cut at that same angle. Thus, the drill bit moves ahead in a long arc until the bore is aiming in a desired direction. Having cut a directional hole arcing away from some original path to a new desired orientation, the drill string is rotated as the motor also independently rotates the drill bit. The drill bit then drills straight ahead.
Pulling the drill string out and replacing it, called "round tripping," is an expensive proposition which loses drilling time, and navigational drilling techniques alleviate the need to round trip between straight and curved sections of well bore. Thus, rather than removing the angle drilling equipment from the end of a drill string, a drilling crew simply begins anew to rotate the drill string. As the drill string rotates, its own rotation of the hydraulic motor and tilt unit is superimposed on the rotation of the bit with respect to the hydraulic motor casing and drill string. Thus, the motor-rotated drill bit is moved around the outside perimeter of the hole by the drill string rotation.
Drill bits are designed for drilling a collinear path with respect to an axis of rotation. Particularly, in diamond bits which have polycrystalline diamond compacts as cutting elements attached to a bit face or to studs protruding from the bit face, each cutting element should sweep a specific region in the formation on each rotation of the bit. A drill bit design presumes attachment directly to a coaxially-rotating prime mover. A hydraulic motor at the end of a non-rotating drill string approaches the design conditions, as does bit rotation by drill string rotation, if no tilt mechanism is installed. In these cases, the bit contacts the formation in an orientation for which the bit was designed. Each cutting element sweeps the surface which it is designed to cut, making repeated sweeps at its diametral position. Along its rotating path, it advances at or near its design rate of penetration into the formation.
However, for straight drilling with a navigational drilling bottom hole assembly, the bit crown rotates with the output shaft of the hydraulic motor but the axis of rotation shared by the output shaft and bit crown precesses around the bore hole. Therefore, an individual cutting element on the bit does not continue to rotate at a constant diametral position in the bore. Further, since the bit is canted off the axis of the hole, each cutting element follows a complex, irregular helical path in the formation.
In contrast, a cutting element located on the nose of a bit at the end of a straight hole drill string should cut an annulus in the earth formation at a radius equal to the distance of that cutting element from the axis of rotation of the bit crown. On each rotation, the cutting element should continue in the same annular track seeing over and over that same annulus as it continues to cut into the formation. Likewise, other cutting elements will cut in their own respective, advancing, rotating paths. On the flank or shoulder portion of a bit crown, a cutting element should be working on an advancing, slightly spiraling groove. The radius corresponds to the distance of the cutting element from the axis of rotation. The spiral advances at the rate of penetration of the bit into the formation. Cutting elements on the gage portion of the crown likewise spiral ahead at the gage radius and the rate of penetration of the drill bit.
However, bit damage is excessive during straight drilling with a navigational drilling bottom hole assembly due to the loads experienced by cutters on a precessing, tilted bit. As the bit's axis of rotation sweeps eccentrically around the centerline of the hole, it creates nonuniform, off-design, and impact loading on the cutting elements.
As the entire bit in such situations is rotating rapidly about the drill string axis as well as about a canted axis defined between the motor and the drill bit, virtually all points on the bit actually precess around the centerline of the advancing hole. The hypocycloidal, tilted path thus defined by each precessing cutting element does not cut in an advancing circle in a single plane into the formation, but distorted circles of varying depth around an ever-changing center.
As a result of the precession and the tilt of the bit, the cutting elements are not in continuous contact with the formation so a reduced number of cutting elements can be in contact with the formation at any time. This reduced number of cutters must still support all the loads generated by drilling. Further, the orientation (side rake and backrake) of cutting elements with respect to the formation being drilled varies on a continuous basis, inducing off-design and non-uniform loads. Meanwhile, the angle of the rotating bit with respect to the drill string also rotating results in cutters which alternately move impotently into empty space, revolving back to contact the formation. The result is a shock or impact load on a cutter as it slams back into the formation. Clearly, at any instant of time, certain cutting elements on the bit face are overloaded, while others see virtually no load.
Thus, several adverse effects result from the motion of the individual cutting elements on a bit disposed on a navigational drilling bottom hole assembly that is drilling a straight hole. First, the hole is oversized, reducing efficiency and requiring that a substantial additional volume of the formation be drilled to advance the bore hole. Second, not seeing the same simple circle or spiral path continuously, a given cutting element is exposed to repeated impact as it moves between the empty bore and the bore wall or uncut formation face, or crosses the paths cut by other cutting elements at random. Third, the cutting elements in general are not uniformly loaded as they were designed to be but see higher and more abrupt maximum loads and lower minimum loads so individual cutting elements are more likely to experience catastrophic failure. Fourth, the effective rate of penetration is slowed since numerous cutting elements are not properly loaded continuously, instead alternately having too little and too much formation material to cut. Fifth, the irregular contacts due to the combination of the cutters' irregular paths and the canting of the drill bit to one side of the oversized hole cause bouncing or chattering of the cantilevered drill bit against the formation. Sixth, cutting elements located at certain positions on the bit, such as at the nose or shoulder, will continue to be loaded more often and more heavily than others.
The end result on the drilling assembly is fatigued parts in the drill string, spalling and fracturing of cutting elements, and premature abrasion and erosion of the drill bit. Exaggerated, uneven wear regions appear in addition to damage to overloaded individual cutting elements.
SUMMARY OF THE INVENTION
What is needed to alleviate the above-noted drill bit problems associated with straight hole drilling using a navigational drilling bottom hole assembly is a drill bit which is not restrained to rotate about the axis of rotation of the hydraulic motor output shaft when the shaft is not coaxial with the drill string above. The concept of the present invention is that a drill crown, if provided with a universal joint between itself and the shank of the drill bit attached to the output shaft of the hydraulic motor, is significantly less constrained than prior art bits. The loading on the bit of the present invention by the drill string thus tends to center the bit around the design center of rotation.
Any load imposed on a cutting element in one location on a drill crown as a result of the resistance of the formation to drilling is balanced against the forces acting on other cutting elements in the crown in an optimized bit design. As a result, a well-designed drill bit crown tends to drill straight ahead along its axis of rotation. Thus, if a drill crown were free to orient itself, it would tend to align its face so that the bit would rotate about its true or design axis of rotation. Such a bit would drill along the axis of rotation for which it was designed even though the power to the crown may come through a shaft of a hydraulic motor canted off-axis. That is, the cutters will cut in the direction of resultant loads. The bit will follow the portions of the formation which receive the most contact from cutters. In other words, the bit will self-align in substantially the designed cutting orientation. Further, the stabilizers will tend to maintain a straighter bore as they are drawn down into the relatively smaller diameter bore cut by a swivel crown bit.
Such a self-aligning bit would still drill in the direction of the axis of the output shaft of a downhole motor when the drill string was stationary. Thus, whether the drill string alone turned, or when the downhole motor turned on the end of a turning drill string, the crown of the bit would align itself about the axis of rotation of the drill string.
In addition, variations in formations can affect bit performance. A bit which could self-orient would have improved effectiveness even on a conventional straight drill string. Moreover, a drill string itself may have multiple modes of dynamic oscillations due to loading and rotation. The need for a self-aligning bit extends to straight drill strings to compensate for flexing and bending of the string.
The present invention discloses a tiltable bit crown which allows the crown face to maintain full contact between the formation being drilled and all the cutting elements in all the above circumstances even though attached to a shaft which has been bent, tilted or canted with respect to the axis of the hole, whether accidentally or for directional drilling. The invention allows the crown to coaxially align itself with the axis of the hole, even during straight drilling with a navigational bottom hole assembly, when the motor and tilt mechanism rotate eccentrically between the drill string and the universal of the bit.
The drill crown according to the present invention comprises a shank and crown tiltably associated to permit separate, intersecting, non-collinear axes of rotation. The drill bit disclosed herein provides a crown tiltably connected to the shank of the bit for both straight and directional drilling. Thus, during straight hole drilling, even with the drill string rotation superimposed upon the motor-induced rotation, a well bore of substantially the same diameter as the design gage of the bit results, rather than the oversized bore drilled by prior art bits. In other words, rotation of the bit of the present invention by a hydraulic motor in combination with a rotating drill string results in the same bore size and bit efficiency as the rotation of the bit solely by an hydraulic motor secured to a non-rotating drill string, or to a drill string or motor wherein the drill bit axis remains coaxial with the drill string axis.
Stated another way, the drill bit of the present invention includes a universal or its equivalent connecting the bit crown to the shank for more efficient downhole drilling of earth formations. The drill bit may improve conventional drilling, directional (nagivational) drilling, and straight drilling with directional drilling apparatus. The bit crown according to the present invention comprises a simple load-bearing universal which permits the bit crown to align itself with its own single axis of rotation to optimize the contact between the cutting elements of the bit and the drilled formation. The drill bit disclosed herein, when used for conventional straight drilling, provides more efficient and smoother drilling with reduced bit damage and wear. It also provides all those benefits when used in directional or navigational drilling. The bit further reduces the abuse of the cutting elements which typically arises from straight drilling in association with downhole directional drilling as conducted with a navigational drilling bottom hole assembly.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a partial cutaway isometric view of the swivel crown bit having a universal joint.
FIG. 2 shows a cutaway elevation view of one embodiment of the swivel crown bit of the invention.
FIG. 3 shows an elevation view of another embodiment of the swivel crown bit of the invention with the crown shown in cutaway.
FIG. 4 shows a cutaway plan view of one possible configuration of the swivel crown bit of FIGS. 1-3 taken at section I--I of FIG. 2.
FIG. 5 shows a cutaway plan view of another alternate configuration of the swivel crown bit of FIGS. 1 and 2 taken at section I--I in FIG. 2.
FIG. 6 shows a cutaway plan view of another alternate configuration of the swivel crown bit of FIGS. 1 and 2 taken at section I--I in FIG. 2.
FIG. 7 shows a schematic elevation view of a drill string (with exaggerated dimensions and angles) configured with a tilt mechanism and a swivel crown bit of the invention.
FIG. 8 shows a partially cutaway elevation view of a flexible sub configuration of the invention.
FIGS. 9-11 show an elevation view of various configurations of flex slots in the flexible sub of FIG. 8.
FIGS. 12A and 12B show an elevation view of a portion of the flexible sub of FIG. 8 with alternate configurations for the flex slots.
FIG. 13 shows a cutaway elevation view of a flexible sub having a shank of reduced cross section for inducing flexure above the crown of the bit.
FIG. 14 shows a cutaway elevation view of an alternate embodiment of the swivel crown bit of the invention.
FIG. 15 shows a cutaway elevation view of a segment of an alternate embodiment of the universal of the swivel crown bit of the invention.
FIG. 16 shows a cutaway elevation view of an alternate embodiment of the swivel crown bit of the invention.
FIG. 17 shows an isometric view of a rectangular configuration of the ways in which the lugs of FIG. 16 travel.
FIGS. 18A, 18B and 18C show alternate embodiments of trunnions which can operate in the ways of FIG. 17 without lugs.
FIG. 19A shows an isometric view of one configuration for spherical trunnions formed on the shank of the bit of FIGS. 14 and 16.
FIG. 19B shows a plan view of a configuration for the spherical trunnions formed on the shank of the bit of FIGS. 14 and 16.
FIGS. 20-21 show isometric views of alternate trapezoidal and rectangular embodiments, respectively, for the lugs in the swivel crown bits of FIGS. 15-16.
FIGS. 22A and 22B show isometric views of alternate embodiments of lugs for the swivel crown bit of FIG. 14, having spherical and cylindrical surfaces, respectively.
FIGS. 22C and 22D show an elevation view and section view, respectively, of an alternate embodiment of the lug of FIG. 22B.
FIG. 23 shows an elevation view of a drill string configured with a single tilt unit (with exaggerated dimensions and angles) and the swivel-crown bit of the invention for straight or directional drilling.
FIG. 24 shows an elevation view of a straight bore and a drill string having a single tilt unit (with exaggerated dimensions and angles) and a conventional bit, rather than the swivel-crown bit of the invention.
FIG. 25 shows an elevation view of a drill string having a double tilt unit (with exaggerated dimensions and angles) and a conventional bit as it transitions from straight to directional drilling.
FIG. 26 shows an elevation view of a canted bit on which the face and gage are not aligned with the working surface of the oversized bore.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
The principles of the present invention can best be seen in FIGS. 1-6 which show one preferred embodiment of the bit 10 with slight variations. Similarly-functioning elements are similarly numbered among the figures. The bit 10 is comprised of crown 12 and shank 14. The shank 14 is connected to crown 12 by one of several means of the present invention designed to give a universal effect to the connection. FIG. 7 shows an elevation view of the bit 10 attached to downhole motor 16 on drill string 18. The universal 20 of FIG. 1 allows the crown 12 of FIG. 7 to align itself in bore 22 despite the angle with respect to the drill string that is imposed by the tilt unit sub 24. Sub is a general term in the drilling industry referring to a component which is assembled within a drill string. Thus, the tilt unit sub 24 of FIG. 7 may be any of several types known in the art. The tilt unit is attached to the outer housing 28 of a downhole motor 16. The outer housing 28 moves with the drill string 18. The drill string 18 is connected to a rotary table and motor drive system or top drive (not shown) at the surface of the earth at the opening of the bore 22.
Referring to FIGS. 1-6, crown 12 has cutting elements 30 (FIG. 2) mounted to its face 32, with gage 36 to align bit 10 in bore 22. From a plenum 38, drilling mud is passed to nozzles 40 which open through the face 32 of crown 12. Column 42 extends from the beginning of the drill string, at the surface of the earth, through the center of the drill string all the way down to shank 14.
In FIGS. 1 and 2, a universal 20 capable of tilting angular displacements attaches the shank 14 to the crown 12. FIG. 1 is a partial cutaway perspective view of a bit 10 employing the universal 20. FIG. 3 shows a view of crown 12 as viewed along section II--II of FIG. 4 with shank 14 not sectioned. FIGS. 4-6 are alternate embodiments of the bit 10 of FIG. 2 looking along section I--I.
A shank 14 comprises a tubular shaft 46 which attaches to the drill string 18 or the end of an output shaft of a downhole motor. At the distal end of shank 14, a spherical element 64 is attached. Spherical element 64 is provided with an extended surface 66 and excavated surface 68. Protruding outwardly from the excavated surface 68 are shank lands 70, preferably extending to a diameter approximately equal to the diameter of extended surface 66. Shank lands 70 are preferably manufactured by leaving residual material when machining excavated surface 68 below extended surface 66 of spherical element 64, best seen in FIGS. 1 and 3.
Fitting against excavated surface 68 to extend away therefrom to a radius equivalent to that of the extended surface 66 are lugs 72. Column 42 extends through spherical element 64 of shank 14 to provide drilling mud to the crown 12.
Crown 12 is configured to have a spherical surface 74 conformed to extended surface 66 of shank 14. Spherical surface 74 extends into bit body 76 and spherical collar 78, which is retained against bit body 76 by keeper 80.
Crown lands 82 are formed in bit body 76 and, in some configurations, in spherical collar 78. Crown lands 82 protrude from the crown 12 toward excavated surface 68 of shank 14. Thus, crown lands 82 would almost completely interfere with shank lands 70 if not for circumferential offset. Crown lands 82 are circumferentially 90 degrees out of phase from shank lands 70 about shank axis 84.
The intervening space between shank lands 70 and crown lands 82 is circumferentially occupied by lugs 72, which are captured radially between excavated surface 68 of shank 14 and spherical surface 74 of bit body 76. Thus, lugs 72 force crown lands 82 to rotate with shank lands 70 about shank axis 84 while allowing crown axis 86 to tilt away from shank axis 84.
Tilt clearance 88 is required above and below crown lands 82. Tilt clearance 88 must be sufficient for the full clearance angle 62 between shank 14 and crown 12. That is, in operation, crown lands 82 will oscillate within the region of excavated surface 68 between extended surface 66 above and below crown lands 82. Shank lands 70, on the other hand, can be continuous with extended surface 66 of shank 14, all moving within the spherical surface 74 of crown 12.
The crown 12, shank 14, or both must typically contain some means to seal against the other, to direct pressurized drilling mud to the face of the crown 12 for cooling and cleaning the cutting elements and removing cut formation debris. In the embodiment of FIG. 1, seal 90 fits into a seal groove 92 cut into spherical surface 74 in crown 12. Seal 90 extends above seal groove 92 to contact extended surface 66 and shank 14 to make a seal. Seal 90 assures that drilling mud conducted through column 42 from drill string 18 into shank 14 passes onto plenum 38 and nozzles 40 in the face of bit body 76 of crown 12. Nozzles 40 feed drilling mud to cutting elements 30 to carry away debris, to cool the cutting elements 30, and to lubricate the contact between the bit and the formation. Seal 90 provides a pressure seal to substantially prevent the mud from escaping back through the universal 20. The seal 90 also prevents erosion of the components of the universal 20.
As shown in FIGS. 1 and 3, shank land 70 has shank land sides 94 which must progress around spherical element 64 with planar symmetry around a plane through shank axis 84 and the "vertical" center of shank land 70. Thus, although shank land sides 94 can be configured to form a trapezoidal cross-section in shank land 70, each point on a shank land side 94 must move in the same plane defined by the movement of shank axis 84 and parallel to the "vertical" centerline of the shank land 70. Otherwise, shank 14 would be rigidly fixed with respect to crown 12. Since the outer surface 98 of shank land 70 is substantially coincident with the extended surface 66 of spherical element 64, clearance above nominal is not necessary between shank land 70 and extended surface 66 at upper and lower ends 100, 102 of shank land 70. Depending on manufacturing, shank land 70 may be contiguous with extended surface 66, within the constraints mentioned above.
Crown lands 82 extend inwardly as part of crown 12, barely maintaining a clearance 104 with excavated surface 68. In addition, an angular clearance 106 exists between spherical element 64 and upper and lower ends 108, 110 of crown lands 82. Angular clearance 106 provides the necessary freedom of relative rotation between shank 14 and crown 12. The shank and crown at the location of clearance 106 also serve as a limiting means whenever upper and lower ends 108, 110 of crown lands 82 contact spherical element 64.
Shank lands 70 and crown lands 82 extend into both the upper and lower hemispheres of spherical element 64. Assembly may be simpler if crown lands 82 and shank lands 70 are formed only in the lower hemisphere of spherical element 64. In that case, the spherical collar 78 need not accommodate shank lands 70. It may act as a stop mechanism for crown lands 82 and accommodate only the simple spherical shape of extended surface 66 of spherical element 64.
Spherical surfaces within the lower hemisphere of spherical element 64 must be load-bearing and must accommodate relative rotation between shank 14 and crown 12. Since the relative rotation (tilting, swiveling) between crown 12 and shank 14 is limited to less than a few degrees, tilt or swivel is a more appropriate term perhaps.
In the embodiment in FIG. 5, lug inner land 112 serves the function of shank land 70 of the embodiment of FIG. 4. Lug outer land 114 serves the function of crown land 82 of FIG. 4. The same kinds of geometrical and load requirements exist in each case. One advantage to the configuration of lug 72 in FIG. 5 is that lug 72 may be made of a tougher material or softer material than either shank 14 or crown 12. Thus, the lugs 72 would absorb shock, although such a material might have poorer wear characteristics. However, lug 72 becomes a completely replaceable part for improved wear characteristics of the remainder of the bit 10. A casting process to produce the hemispherical lugs 72 could make reproducible, accurate, and inexpensive replacement parts for long operation of bit 10. Note that the lugs 72 in all configurations carry rotary power to the drill bit and also carry axial compressive forces to maintain the rate of penetration of bit 10.
Lug inner and outer lands 112, 114 rotate within shank slots 116 and crown slots 118, respectively. Each configuration must gimbal the crown 12 in two degrees of freedom with respect to the shank 14.
In the embodiment of FIG. 6, bit 10 is provided with shank races 120, crown races 122, and lug races 124 in shank lands 70, crown lands 82, and lugs 72, respectively. The planar symmetry of shank land 70 and crown land 82 is still required as discussed above. Nevertheless, bearings 126 are captured by shank races 120, crown races 122, and lug races 124 to provide frictionless tilting of crown 12 with respect to shank 14.
Although shown here as spherical bearings, bearings 126 could be rollers with shank, crown and lug races 120, 122, 124, respectively, shaped accordingly to have flat, curved or circular surfaces to allow bearings 126 to roll axially with respect to shank axis 84. The configuration of FIG. 6 has several moving parts, but lugs 72 and bearings 126 could be easily replaceable elements made of a softer or otherwise less durable material than shank lands 70 and crown lands 82.
FIGS. 14-22 show alternate embodiments for the universal 120 of the bit 10. In FIG. 14, the shank 14 contains four balls, trunnions 128, either integral or securely attached thereto. Trunnions 128 positioned every 90 degrees about shank axis 84 are fitted into sockets 130 formed in lugs 72. Lugs 72 move in spherical ways 132 in crown 12. The view of the bit 10 of FIG. 14 may be identical from a position rotated 90 degrees from the view shown. Thus, bit 10 has a true universal.
Crown lands 82 are basically the continuation of the material of crown 12 between lugs 72. This configuration provides for tilting of shank 14 into or out of the plane of the page about trunnions 128 in sockets 130. Thus, all lugs 72 are restrained to move between the crown lands 82 of crown 12. The additional degree of freedom provided by trunnions 128 in sockets 130 allows the necessary movement in orthogonal planes to give the universal effect.
In FIG. 15, trunnions 134 formed as part of crown 12 fit into sockets 130 in lugs 72 which slide in ways 136 formed in shank 14. This configuration has certain inaccuracies since ways 136 are parallel, not circular. Lugs 72 will, therefore, not have a constant tolerance in ways 136 upon tilting of crown 12. Thus, the concept of FIG. 15 is not a true universal joint, but for the small angles required is a legitimate configuration.
Similarly, FIG. 16 further illustrates the concept of FIGS. 14 and 15. That is, trunnions 128 attached to shank 14 ride in sockets 130 formed in lugs 72 which slide in ways 138 formed in crown 12. Since ways 138 are parallel to one another rather than being spherical like the spherical ways 132 in FIG. 14, the perpendicular distance with respect to ways 132 between lugs 72 on opposing sides of crown 12 varies slightly with the tilting of shank axis 84 with respect to crown 12. Thus, FIG. 16 is not a true universal, but for small angles operates effectively as one. The major movements required of a universal can be accomplished with the configuration of FIG. 16. FIG. 17 shows the geometrical relationship of ways 138 in the bit 10 of FIG. 16.
The simplest shanks 14 for moving in the ways 138 of FIG. 17 are shown in FIGS. 18A-C. The shank 14 is provided with rockers 133 to replace the trunnions 128 and the lugs 72 which move in ways 138 configured as in FIG. 17. By proper choice of a radius 141, the rockers 133 could move in the ways 138 to produce a universal effect while maintaining the shank 14 centered in the crown 12 of the bit 10. Likewise, a proper radius 143 or 145 on each rocker 133 assures proper load-bearing capacity in the shank 14 for driving the crown 12. FIGS. 19A and 19B show a perspective view of trunnions 128 in possible configurations of shank 14. The trunnions 128 may be integrally formed on the shank 14 and filleted.
FIGS. 20 and 21 show possible configurations of lugs 72 for the configuration of FIGS. 15 and 16, while FIGS. 22A-D show lugs 72 to fit the curved surface 139 of FIG. 14, which is preferably spherical (FIG. 22A), but may be cylindrical (FIG. 22B) and may include a trapezoidal cross-section (FIGS. 22C-D). Cylindrical surfaces may replace spherical ways 132. That is, spherical ways 132 may generally be replaced by circular slots having trapezoidal or rectangular cross-sections in which lugs 72 slide in circular arcs.
FIGS. 8-13 show another embodiment of the invention to achieve a universal effect. Flexible sub 44 is made of a continuous but flexible material to operate as the universal. Such a device relies on the elastic deflection of reduced sections of material to accommodate the tilting movement of the crown, usually less than one degree, but sometimes as much as four degrees. Flexible sub 44 can be thought of as a special kind of shank 14 having a shaft 46 cut at its outermost diameter with flex slots 48 extending to a depth 50 sufficient to render the flex sub 44 more easily bendable. The flex slots 48 are preferably provided with anvils or stops 52 mounted on either side of flex slots 48 to limit the bending of flexible sub 44 at any given flex slot 48. The anvils or stops 52 may be made of the same material or a material substantially harder or tougher than the material of shaft 46 in which flex slots 48 are formed. Different sizes of stops 52 may be used to adjust the clearance 49 between the stops and to increase or decrease effective flexibility of the flexible sub 44. Flexible sub 44 is typically a steel part, while anvils or stops 52 might be a hardened steel or a tungsten carbide alloy.
The design of flex slots 48 might be narrow or broad. Similarly, flex slots 48 could be relatively straight as in FIGS. 9 and 10, having a radius of curvature 54 to distribute stress and prevent stress concentrations during bending. Alternatively, as in FIG. 11, flex slot 48 can be a transverse cylindrical bore cut through at one side to the outside surface 56 of flex sub 44. The configuration of flex slots 48 used should balance maximum distribution of bending stresses over a large radius, against a radius small enough to allow the maximum number of flex slots 48 to be cut into flex sub 44. Anvils or stops 52 can be placed outside of a flex slot 48 or inside.
The flex slots 48 may be arranged as in FIG. 8 on opposite sides of flexible sub 44, with alternating pairs of flex slots 48 being orientated at a 90° angle with respect to each other. The flex slots 48 might be staggered as in FIG. 12A rather than being directly opposite one another. In this way, greater torsional loads could be carried in the flexible sub 44 since the cross-section normal to the axial direction is not as thin as in the configuration of FIG. 4.
Conceivably, flex slots 48 might be staggered even further as shown in FIG. 12B. This configuration can allow tremendous torques to be passed down the solid portions of flexible sub 44 while allowing substantial bending at the flex slots 48. Nevertheless, the preferred embodiment at present is for slots as configured in FIG. 8.
Flexible sub 44 is secured to crown 12. The preferable attachment means is a threaded connection 57 in which flexible sub 44 is threadedly engaged until it comes to rest against a stop 58 on the crown 12.
Some configurations could cause more even loading and deflection. Each configuration can be made sufficiently strong in torsion while still bending adequately. One advantage of symmetry, however, is smoother operation.
In the embodiments of FIGS. 1-6, shank 14 and crown 12 are configured to form a true universal joint which may be designed to permit a relatively large angle of tilt. The flexible sub of FIG. 8, in contrast, is functional because only a small angle of tilt is required in most applications. The flexible sub 44 basically comprises a shaft 46 made discontinuous or otherwise of reduced section at its outermost fiber to improve its flexibility in bending.
Because it will bend with respect to the crown 12, flexible sub 44 may be provided with either a relief radius 60 or a clearance angle 62 or both. The crown 12 may also serve as a stop to prevent excessive tilting with respect to shank 14.
The three operational scenarios of interest are understood by reference to FIGS. 23-25. It should be understood that angles and sizes are necessarily exaggerated for clarity in FIGS. 23-25. The scenarios include straight drilling on a conventional drill string, straight drilling on a directional or navigational bottom hole assembly at the end of a rotating drill string and directional or navigational drilling with a bottom hole assembly at the end of a non-rotating drill string.
In the first instance (not illustrated), conventional straight drilling benefits from the apparatus of the invention by improved efficiency. Less material must be drilled because the orientation of the bit 10 is unaffected by any wobbling or bending of the highly-loaded drill string. Increased efficiency improves the rate of penetration as well as the wear characteristics and breakage rates of the bit 10.
In the second instance, a conventional drill bit secured to the output shaft 148 of motor 16 of the bottom hole assembly for navigational drilling maintains a slight angle of tilt with respect to drill string 18. The drill string 18 can be selectively rotated to control the effect of the bottom hole assembly. If the drill string 18 is stationary, the effect is directional drilling. If drill string 18 rotates, then bit 10 precesses around bore 22 defined by bore axis 144 as described in the background (see FIG. 7). By contrast (FIG. 23), if bit 10 of the type of the present invention is employed, then both drill string 18 and output shaft 148 of downhole motor 16 may rotate but bit 10 will align itself with the smallest possible bore 22 to balance the forces on it. Efficiency and rate of penetration improve. Wear and breakage rates are likewise improved dramatically by the properly-oriented and loaded bit 10.
In the third instance (FIG. 25), drill string 18 is not rotating. Output shaft 148 is rotating, so bit 10 has only one axis of rotation, the motor axis 146. In that case, bit 10 of the invention will align itself with motor axis 146 and drill a directional bore. The benefits correspond to straight drilling of the first instance above.
FIG. 23 shows bore 22 with a navigational drilling system having stabilizers 26 mounted to single tilt unit 156 and downhole motor 16, a bottom hole assembly generally as disclosed in U.S. Pat. No. 4,667,751. Single tilt unit 156 has a single bend 158 to cant the output shaft of downhole motor 16 with respect to drill string 18. Output shaft 148 is oriented such that rotation of output shaft 148 with concurrent rotation of drill string 18 will cause stabilizers 26 to rotate inside bore 22 while output shaft 148 also rotates with respect to drill string 18. The effect on crown 12 of bit 10 is to swivel about shank 14, aligning itself with drill string 18. Bit 10 then drills a straight hole of substantially the design gage of bit 10 to the extent possible. For a bend 158 having a small tilt angle 160, a very satisfactory alignment of crown 12 may be made with respect to drill string axis 152.
Without the swivel-crown bit of the instant invention, FIG. 24 would describe the motion of a bit 10 in a bore 22. Single tilt unit 156 having bend 158 to tilt downhole motor 16 with respect to drill string 18 aligns the output shaft 148 of downhole motor 16, thus assuring that bit 10 will precess around bore 22 along cutting surface 164. Diameter 23 of bore 22 is measurably larger than crown 12. Further, crown 12 is not aligned with cutting surface 164, so it tends to bounce and chatter against bore wall 172, increasing bit wear.
FIG. 25 shows a bottom hole assembly with a double tilt unit 166 having upper bend 168 and lower bend 170, which together tilt drill bit 10 with respect to downhole motor 16 and drilling string 18. Stabilizers 26 prevent double tilt unit 166 from rubbing the bore wall 172 of bore 22. This bottom hole assembly is similar to one of the embodiments of U.S. Pat. No. 4,739,842. For directional drilling, crown 12 of bit 10 rotates about output shaft 48 with a non-rotating drill string 18. Stabilizer 26 will follow crown 12 into directional bore 174, which has a directional bore diameter 176 cut out to fit crown 12. If bit 10 is a conventional bit, as in FIGS. 24 and 25, then bore diameter 23 is larger than crown 12 and stabilizers 26 in the straight portion of bore 22. In the directional bore 174, directional bore 176 generally corresponds to the diameter of crown 12, but may still be slightly oversize or out of round.
If instead the bit 10 of the instant invention is used, as shown in FIG. 23, then bore diameter 23 remains the size of crown 12 during both straight and directional drilling. If downhole motor 16 is the only motive means rotating shank 14, the bore 22 is directional and fits crown 12. If drill string 18 is rotating and output shaft 148 is rotating with respect to drill string 18 in addition, crown 12 aligns with the drill string 18. The bend of the single unit 156 or dog leg of double tilt unit 166 rotates between crown 12 and drill string 18 like a jump rope.
One beneficial result of the use of the instant invention in straight hole drilling is that less volume of a formation needs to be drilled. Straight hole drilling is the majority of any bore 22 of a well in an earth formation, so the benefits can be substantial.
As shown in FIG. 26, a crown 12 which is not in contact with a formation may have space to wobble within bore 22, and forces 178 concentrated at the point or line of contact 180 of crown 12 must support a load in excess of the designed capacity. If instead shank 14 tilts with respect to crown 12, then a force 178 acting on only one side of crown 12 will tend to align crown 12 with the face 182 of the formation so that the forces 178 are distributed over the bit face 184. Thus, the universal 20 of the instant invention promotes less cutter wear, less cutter breakage, higher efficiencies, higher rates of penetration and smaller bore diameters 23, optimizing the use of a crown 12 of a bit 10 in both directional and straight drilling.
Specific directional drilling apparatus have been discussed in order to illustrate the invention. However, the self-aligning crown 12 achieved by the invention and the universal 20 which provides such features are equally applicable to most drilling configurations. Drilling performance of conventional directional drilling downhole assemblies (including kick-off assemblies) can be improved by the invention. Whether fixed in place on a drill string or selectively actuated from the surface while in service, directional tilting mechanisms will benefit from the bit 10 of the invention. As discussed, benefits accrue to a drilling rig using the bit 10 in virtually all conventional drill string configurations.
Likewise, the invention is described and illustrated with a crown 12 of the type known as a "drag bit" or "fixed cutter." The cutting elements 30 are fixed with respect to the crown 12. The cutting elements 30 are thus dragged along against the formation at the same rate of rotation as that of the crown. Nevertheless, the crown could be configured on its outer surfaces to have what is called a "tri-cone" or "rock bit" configuration. In that configuration, well known in the art, multiple roller cones mounted in a recess in the crown 12 rotate while carrying "teeth" distributed around the exteriors of the cones. The "teeth," called cutting elements also, cut into a rock formation with a compound rotary motion, since the roller cones rotate with respect to the crown 14 and the crown rotates with respect to the formation. The instant invention, by allowing self-alignment of the crown 12, equalizes the loads on the teeth and bearings of the roller cones. Thus, reduced tooth and bearing failures result from the load-balancing effect of the self-alignment provided by the invention.
The features of the embodiments illustrated and described herein can be combined to form other configurations by one having ordinary skill in the art. Without limiting the scope of the claimed invention to the disclosed embodiments, the invention disclosed herein is limited only by the claims. | A drill bit for drilling subterranean formations includes a device to provide a "universal" effect between the shank and crown for self alignment of the crown with the bore hole in the formation. The bit is suitable for downhole assemblies configured for straight drilling, directional drilling and navigational drilling. The device can be incorporated into both drag bits and roller-type "rock" bits. Preferred embodiments include a flexible sub connecting the crown to the shank portion and having reduced stiffness relative to the drill string. Alternatively a spherical universal joint or trunnion type universal is used. Replaceable lugs increase durability and reliability of the universal. The device equalizes the loads on cutters while reducing wear, average loads, and impact loads on cutters. Bore hole diameter and chatter of the bit in the bore hole are reduced, promoting maximum efficiency and rate of penetration as wobble and precession are minimized. | 4 |
This is a continuation of application Ser. No. 08/238,919, filed May 6, 1994, now abandoned.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a composition which due to its cleaning abilities can break down, liquify, and clean away oil, grease, tar, and carbon residue deposits from the interior walls of pipes and coils connected to compressors of domestic and commercial refrigeration systems. When the compressor of a refrigeration system fails, the heat generated by the failure of the compressor results in refrigeration oil being transformed into tar and carbon deposits which line the interior walls of the pipes and coils of the refrigeration system and thereby render them contaminated. The cleaning composition of the invention is safe for both the individuals cleaning the pipes and coils of such refrigeration systems as well as the environment. The composition of the invention is free from ozone depleting substances, can be safely released into the atmosphere, is biodegradable, and replaces both flammable and chlorinated solvents.
2. Description of the Prior Art
Solvents and related preparations for breaking down, liquefying, and cleaning away oil, grease, tar and carbon residue deposits from the interior walls of pipes and coils attached to compressors of domestic and commercial refrigeration systems have been typically hazardous to both the environment and the individuals working with such systems. Such solvents and related preparations typically contain ozone depleting chlorinated substances which are released into the atmosphere, are non-biodegradable, and/or are flammable.
SUMMARY OF THE INVENTION
The invention provides a stable multi-purpose cleaning composition for cleaning the pipes and coils of domestic and commercial refrigeration systems. The cleaning composition comprises a single phase solution having as a major constituent one or more compounds from the glycol-ether group, including diethylene glycol monobutyl ether, dipropylene glycol monomethyl ether, tripropylene glycol methyl ether, propylene glycol methyl ether acetate, dipropylene glycol methyl ether acetate, and ethylene glycol n-butyl ether, as well as a minor portion of the total volume of at least one of the compounds from the alcohol and/or ketone chemical group. The alcohol group includes, butanol, propanol, ethanol, methanol, and isopropanol. The ketone group includes methyl ethyl ketone, methyl propyl ketone, methyl butyl ketone, ethyl propyl ketone, ethyl butyl ketone, and propyl butyl ketone.
The cleaning composition of the invention has a phased (timed) evaporation rate, leaves no residue, is non-flammable, is biodegradable, can be vented to the atmosphere, and does not contaminate the lubricating oil of refrigeration systems.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In accordance with the invention, compounds from the glycol-ether group, blended with compounds from the alcohol and/or ketone groups, produce an environmental safe composition with a "phased" evaporation rate and with above average cleaning abilities which can break down, liquify and clean away oil, grease, tar and carbon residue deposits from the interior walls of pipes and coils connected to compressors of domestic and commercial refrigeration systems.
The need for the composition of the invention is especially important when there is a failure of the compressor motor in a refrigeration system. The heat generated from the compressor motor failure results in refrigeration oil being transformed into tar and carbon deposits which line the interior walls of the pipes and coils of the refrigeration system, thereby rendering them ineffective for heat transfer functions. If these contaminants are not removed, they can cause a repaired or replacement compressor motor to fail again. A severe burnout occurs when the contaminants resulting from an overheated motor are pumped through the refrigerant system while the motor can still run. The contaminants created by a burnout can include moisture, acid, soot, varnish and hard carbon, and copper plating. Overheating of the motor can release moisture which will travel through the refrigeration system. Moisture and dirt can also enter a refrigeration system through careless assembly, service or maintenance. Moisture in a refrigeration system can cause oil sludge which reduces the lubrication properties of the oil and blocks oil passages and screens. Moisture can also react with the refrigerant to form hydrochloric and hydrofluoric acid. These acids can cause corrosion of metals and breakdown of the insulation of the motor windings. If such acids cut through the insulation on the terminal wires of the compressor motor, the motor will short out and fail.
Soot, another contaminant, is generally a soft carbon material caused by charring of the insulation and oil. It is usually confined to the compressor unless the compressor continues to run for an extended period of time after the burnout. Varnish and hard carbon are cause by excessive heat and are the most difficult of all contaminants to remove. Because the compressor is the warmest element in the system at the time of the burnout, most of the varnish and carbon deposits occur in the compressor. Copper plating is the result of a combination of factors such as moisture, the type of refrigerant used, and excessive temperatures. Copper ions are carried to bearing surfaces where they are deposited. The gradual build-up of copper on bearing surfaces reduces the clearances and results in increased friction and wear and eventual seizure. To prevent failure, the contaminants created by a compressor motor burnout must be removed from the system before placing it back into operation.
While satisfying the need for an effective interior pipe and coil cleaner, the invention is also safe to both the environment and to the individuals working with refrigeration systems. The composition of the invention is free from ozone depleting substances, can be released into the atmosphere, is biodegradable, and replaces both flammable and chlorinated solvents. The composition of the invention is blended using groups of compounds to produce a "timed or "phased" evaporation rate which enables the composition of the invention to evaporate in stages, thereby eliminating the possibility that any residue remains within the pipes and coils of the refrigeration system. The glycol-ether group is particularly effective in breaking down, liquefying and cleaning away oil, grease, tar, and carbon, which are found on the interior walls of the pipes and coils of refrigeration systems, both before and after failure of a compressor and the heat generated by such failure.
The cleaning composition comprises a solution such as a single phase solution having as a major constituent of one or more compounds from the glycol-ether group including ethylene-glycol based glycol ethers of:
diethylene glycol monobutyl ether;
ethylene glycol n-butyl ether;
diethylene glycol monomethyl ether;
diethylene glycol monoethyl ether;
ethylene glycol monopropyl ether;
diethylene glycol monopropyl ether;
ethylene glycol monobutyl ether; and
including propylene glycol-based glycol ethers of:
tripropylene glycol methyl ether;
propylene glycol methyl ether acetate;
dipropylene glycol monomethyl ether;
propylene glycol monopropyl ether;
propylene glycol monomethyl ether;
propylene glycol monobutyl ether; and
dipropylene glycol monopropyl ether.
The cleaning composition also comprises a solution such as a single phase solution having as a major constituent of one or more compounds from the glycol-ether group including propylene-glycol based glycol ethers of trimethylene glycol monomethyl ether and trimethylene glycol monoethyl ether.
The cleaning composition further comprises a solution having a minor constituent of one or more compounds from the alcohol and/or ketone chemical group.
The alcohol group includes:
butanol
propanol ethanol
methanol, and
isopropanol.
The ketone group includes:
methyl ethyl ketone;
methyl propyl ketone;
methyl butyl ketone;
ethyl propyl ketone;
ethyl butyl ketone;and
propyl butyl ketone.
By way of example, the major constituent of the cleaning composition may be at least 85% of compounds from the glycol-ether group. Further by way of example, the minor constituent of the cleaning composition may be up to 15% of the compounds from at least one or a mixture of the alcohol and ketone chemical group.
PROPERTIES OF ALCOHOL COMPOUNDS
__________________________________________________________________________I. IDENTIFICATIONProduct Name: Isopropanol, anhydrousChemical Name: Isopropyl alcohol Chemical Family: alcoholsFormula: (CH.sub.3).sub.2 CHOH Molecular Weight: 60.10Synonyms: Isopropyl alcohol; 2-propanol; dimethyl carbinolCAS # 67-63-0 CAS Name 2-PropanolII. PHYSICAL DATABoiling Point, 82.26° C. (180.07° F.) Freezing Point -88.5° C.760 mm Hg (-127.3° F.)Specific Gravity 0.7864 AT 20/20° c. Vapor Pressure 33 mm Hg(H.sub.2 O = 1) At 20° C.Vapor Density 2.07 Solubility In Complete at 20°(air = 1) Water, % by wt.Percent Volatiles Evaporation Rate 2.88By volume (butyl acetate = 1)Appearance and Odor Colorless liquid; characteristic odorGLYCOL PROPERTIES Physical Data: Chemical name: Dipropylene Glycol Monomethyl Ether Chemical family: Glycol EthersBoiling Point: 363 F., 104 C.VAP Press: .55 mmHg @ 25 C.VAP Density: 5.14SOL. in Water: InfinitelySP. Gravity: .950 @ 25/25 C.Appearance: Clear, colorless liquid.Odor: Information not available. Fire and Explosion Hazard Data: Flash Point: 175 F. Method Used: TCC Flammable Limits LFL: 1.1 vol % @ 100 C. UFL: 14 vol % @ 150 C.GLYCOL PROPERTIESI. IDENTIFICATIONChemical Name: Diethylene glycol monobutyl etherChemical Family: Glycol ethersFormula: C4H9O(C2H4O)2HMolecular Weight: 162.23Synonyms: Butoxydiethylene glycol; 2-(2-butoxyethoxy) ethanol;butoxy diglycolCAS # and Name: 112-34-5 Ethanol, 2-(2-butoxyethoxy)II. PHYSICAL DATABoiling Point, 760 MM Hg: 230.6 C. 447.1 F.Specific Gravity (H2O = 1): 0.9536 AT 20/20 C.Freezing Point: -68.1 C. -90.6 F.Vapor Pressure AT 20'C.: 0.01 mmhG at 20 C.Vapor Density (AIR = 1): 5.6Evaporation Rate (Butyl Acetate = 1): <0.01Solubility in Water by wt: 100% AT 20 C.KETONE PROPERTIESCAS # 000078-93-3Formula: CH (3)COC(2)H(5)Chemical Family: KetoneChemical Name and Synonyms: MEK; 2 butanoneIngredient Percent TLV__________________________________________________________________________Methyl ethyl ketone (MEK) 100 PEL/TLV200 ppm(2 Butanone) STEL 2 = 300 ppm(CAS #78-93)<> OSHA/ACGIHPHYSICAL/CHEMICAL PROPERTIES OF CLEANING COMPOSITIONBoiling Point (°F.): 377 Specific Gravity (H2.sub.o = 1) : .936Vapor Pressure @70° F:.304 Melting Point: noneVapor Density(Air=1):5.06 Evaporation Rate:Solubility in Water: Complete (Butyl acetate = 1): .838Appearance & Odor: Clear with Characteristic OdorFlash Point (°F.): 179 Flammability Limit: Let 1.1 UEL 13.5Extinguishing Media: Water Fog, CO2, Dry chemical, UniversalFoams.Composition has autoignition temperature of approximately 350Degrees F.__________________________________________________________________________
Examples of the Cleaning Composition of the Inventiton by Volume are:
______________________________________ Diethylene Glycol MethylExample Monobutyl Dipropylene Glycol Isopropyl EthylNo. Ether Monomethyl Ethers Alcohol Ketone______________________________________1 50% 40% 6% 4%2 19-80% 19-80% 1-15% 0%3 19-80% 19-80% 0 1-15%______________________________________
The maximum percentage of the major constituent of the cleaning composition from the glycol-ether group must be no more than 99% with the balance being at least one of the compounds of the alcohol and ketone chemical groups. In order to insure that the cleaning composition is non-flammable, the minor constituent of one or more of the compounds from the alcohol and ketone groups must be not more than 15% with the balance being at least one of the compounds from the glycol-ether group. In order for the cleaning composition to retain its phased (timed) evaporation rate, the minor constituent must comprise no more than 15% of one or more of the compounds from the alcohol and/or the ketone chemical groups.
In use, the cleaning composition is introduced into the pipe and coil configuration of a refrigeration system following a failure of the system such as that of the compressor motor which results in contamination and deposits on the interior surfaces of the pipes and coil. When the compressor with the motor is removed after failure, access is made available to the pipes and coils. The cleaning composition is then introduced by pumping or by gravity flow into the pipes and coils. The cleaning composition is then left within the pipes and coils for a period of time to enable the cleaning composition to dissolve any oil, grease, tar, and carbon residues within the pipes and oils. The cleaning composition with the dissolved contaminants are then permitted to flow out of the pipes and coils. Thereafter any cleaning composition remaining within the pipes and coils will rapidly evaporate.
The cleaning composition with the dissolved contaminants therein can also be removed from the pipes and coils by applying pressured gas or compressed air to the pipes and coils, thereby discharging the cleaning composition and the dissolved contaminants therein.
Once the cleaning composition is removed from the pipes and coils with the dissolved contaminants, the refrigeration system is immediately ready for reassembly, i.e. the connecting of a replacement or repaired compressor, the sealing of the system, and finally the recharging of the system with refrigerant. | The disclosure relates to a stable multi-purpose cleaning composition for cleaning the pipes and coils of domestic and commercial refrigeration systems. The cleaning composition comprises a single phase solution having as a major constituent one or more compounds of the glycol-ether group, and a minor portion of the total volume of the cleaning composition being at least one of the compounds from one of the alcohol and ketone chemical groups. The cleaning composition of the disclosure has a phased (timed) evaporation rate, leaves no residue, is non-flammable, is biodegradable, can be vented to the atmosphere, and does not contaminate the lubricating oil of refrigeration systems. | 2 |
FIELD OF THE INVENTION
[0001] The present invention relates in general to reinforcing structures and more particularly to materials for strengthening existing structures without substantial change to the appearance of the structures.
BACKGROUND OF THE INVENTION
[0002] Many existing buildings throughout the world are in need of reinforcement to help them resist damage by earthquake, violent storms, acidic atmosphere, vibrations due to vehicle traffic, or similar threats. Many older buildings, especially, were designed to handle large compressive forces but are not resistant to lateral forces.
[0003] Buildings that are not resistant to sudden lateral force need to be reinforced for the safety of people who live or work in, or visit the building. Some buildings have considerable historical or artistic value and must be protected from disasters and environmental deterioration for their own sakes.
[0004] Some methods exist for reinforcing existing buildings. One that is used all over the world is wrapping a structure with fiberglass textile that is impregnated with epoxy. This method is taught in different forms in U.S. Pat. Nos. 5,043,033, 5,649,398, and 5,657,595. A means of connecting different components of a structure using ductile fiber anchors is taught in U.S. Pat. No. 7,207,149 and incorporated herein by reference.
[0005] The methods of U.S. Pat. Nos. 5,043,033, 5,649,398, and 5,657,595 are effective and can be performed with little intrusion on the occupants and visitors of the building being reinforced. A disadvantage to these methods is that they use some specialized materials that are not readily available in all locations. As a result, the materials are shipped from centralized distribution centers, sometimes to remote locations that are difficult to reach. The shipping and round transportation of heavy materials adds significantly to the cost of the project.
[0006] Another disadvantage of the wrapping methods is that the materials readily available on the market are not good matches in color and texture with old buildings. There are many buildings all over the world that are constructed of native stone, brick from local clay, or that are coated with plaster made with local minerals. As a result, the materials of the methods mentioned above, such as epoxy and fiberglass, may not match the color or texture of a given building.
[0007] Yet another disadvantage to the method discussed above is that some of the materials, particularly epoxy, are less fire resistant than conventional stone, brick, or plaster construction. It is desirable that a method for increasing a building's strength should also increase its fire-resistance, or at least not degrade it.
[0008] To avoid the disadvantage of the flammability of epoxy or other organic polymers, the textile could be coated with an inorganic hardenable paste such as mortar. However, this leads to a different disadvantage, which is that inorganic mortars are alkaline and tend to degrade ordinary fiberglass. Special alkaline-resistant glass textile is available, but is quite expensive. This has discouraged the use of glass textile with mortar for reinforcement of structures. Graphite carbon or aramid fiber textiles would be compatible with mortar, but these textiles are also very expensive and not widely available in all countries.
SUMMARY OF THE INVENTION
[0009] The present invention is a system of materials and methods for reinforcing structures using some locally derived materials. The system includes a textile wrap attached to the structure with fiber anchors and a finishing layer of mortar made with grit and aggregate that was obtained from sources in the vicinity of the structure being reinforced.
[0010] The textile is composed of fibrous basalt, which is resistant to alkaline and compatible with inorganic mortar. The textile is typically an open-weave fabric that is strong and ductile. The fabric is attached to the structure in a ductile manner, such as with fiber anchors as taught in U.S. Pat. No. 7,207,149. The fiber anchors are preferably also created from basalt fiber.
[0011] A mortar finishing material is mixed, beginning with a hardenable liquid matrix, such as slurry of calcined mineral particles that harden to create a solid mortar after being mixed with water. Grit, aggregate, or both are added to the hardenable liquid matrix. The grit or aggregate add color and texture to the mortar finishing material.
[0012] The reinforcing system is intrinsically fire resistant and does not increase the fire risk to a structure.
[0013] By using grit and aggregate that are mined or quarried locally, it is often possible to match the color and texture of the original building very well. The final appearance of the reinforced structure is relatively unchanged from the original, possibly historic, appearance. Further, the ability to use local mineral materials saves money on shipping material to a remote location.
[0014] Utilizing local minerals for the mortar finishing material is made possible by the use of basalt fiber textile and fiber anchors.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a top plan view, partly cut away, of the reinforcement system of the present invention, as used to strengthen a wall of a building.
[0016] FIG. 2 is a sectional view, taken on line 2 - 2 of FIG. 1 .
[0017] FIG. 3 is a top plan view of the reinforcement system of the present invention, as used to strengthen an expansion joint of a structure.
[0018] FIG. 4 is a sectional view, taken on line 4 - 4 of FIG. 3 .
DETAILED DESCRIPTION OF THE INVENTION
[0019] FIG. 1 is a top plan view of the reinforcement system 10 of the present invention, partly cut away. FIG. 2 is a sectional view of reinforcement system 10 , taken on line 2 - 2 of FIG. 1 , as used to strengthen a structure 100 , for example a wall 110 of a building.
[0020] Reinforcement system 10 include alkaline-resistant textile 20 stretched over wall 110 . Textile 20 is attached to wall 110 with a plurality of fiber anchors 30 . A mortar 50 , containing mineral products preferably obtained in the same geographic region as structure 100 , is spread over textile 20 and fiber anchors 30 .
[0021] Textile 20 is preferably a lightweight, mesh fabric, woven or knit of suitable ductile, strong, and alkaline resistant fibers such as basalt. Conventionally, structures have been reinforced with fabrics made of glass fibers. Ordinary glass fabric must be covered with a protective finishing material that is pH neutral, that is, neither strongly alkaline nor acidic. Many alkaline or acidic materials, including cementitious materials such as mortar and concrete, degrade glass and weaken it. For this reason, structural reinforcing systems that include glass fiber fabric also typically include a finishing layer of epoxy or polyurethane, which are substantially neutral.
[0022] Of course, other alkaline-resistant fibers with good ductility and high tensile strength may be used to create textile 20 in place of basalt. The choice of specific fiber for textile 20 may be made for each application based upon availability, strength, and cost. Basalt is found to be the preferred material at this time, but other materials may become available in the future.
[0023] Test results show that system 10 greatly increases the load-bearing ability of wall 110 even if the weave of textile 20 includes openings as wide as three or four inches across, although 1 inch across is a more typical size. A plain or twill weave with square or rectangular openings has been found to be convenient to apply and to provide sufficient strength and ductility. Textile 20 is typically woven from yarns or bundles consisting of many individual thin filaments of basalt fiber.
[0024] Textile 20 is stretched over surfaces of various structural elements of a structure 100 to be reinforced. Panels of textile 20 may be wrapped over interior or exterior corners so as to connect different walls 110 , or to connect a wall 110 to a ceiling, or other combinations as appropriate. Textile 20 may be temporarily attached to wall 110 by suitable clips, staples, or adhesive.
[0025] In the case of structures 100 that are built of fragile materials, or that have been damaged by weathering or environmental degradation, it is preferable that the mesh opening size be small, such as 0.5 inch across.
[0026] Many types of structural element can be reinforced by using textile 20 to connect walls 110 to floors or ceilings, columns or beams to ceilings, roofs to walls 110 , and so on.
[0027] The next step in the reinforcement method is to permanently attach textile 20 to wall 110 or other structure using suitable ductile connecting means, such as a plurality of fiber anchors 30 , as are well known in the art. Fiber anchors 30 are created by boring a hole through an opening in textile 20 and into the underlying wall 110 . A length of fiber roving, preferably also composed of fibrous basalt, is inserted into the borehole with a free end extending above textile 20 .
[0028] A backfill material, such as grout or polymeric adhesive, is pushed or injected into the borehole. The free end of the roving is attached to the outer surface of wall 110 and over textile 20 , such as with adhesive or mortar. The backfill material retains the roving within the borehole such that fiber anchor 30 forms a sort of large pin attaching textile 20 to wall 110 . Fiber anchor 30 is the most preferred ductile connecting means for system 10 because fiber anchor 30 spreads forces over a broad area and so is unlikely to pull out from wall 110 as a mechanical fastener might, or pull off a section of wall 110 as a surface adhesive might.
[0029] The final process is to cover textile 10 and fiber anchors 30 with a mortar finish coat 50 . Mortar finish coat 50 covers textile 20 so that it will not be damaged by weather, or snagged. Mortar 50 contacts and adheres to the original surface of wall 110 through the openings of the weave of textile 20 , embedding textile 20 and helping spread any large lateral forces such as from earthquake or wind. Mortar 50 mechanically holds textile 20 in place near wall 110 but cannot entirely take the place of ductile connection means such as fiber anchors 30 .
[0030] Mortar finish coat 50 is largely for creating a uniformly textured and colored surface for the reinforced wall 110 . Conventional epoxy and glass fiber textile reinforcement typically gives a structure a smoother texture and slightly hazy coloration. Although the epoxy can be covered with paint of other finish, mortar is not advised due to possible degradation of the glass fiber.
[0031] Mortar finish coat 50 works well for replicating the appearance of original concrete, stucco, or plaster walls 110 . With additional modeling and coloring work, mortar finish 50 can even replicate the appearance of historical stone or brick walls 110 .
[0032] Mortar 50 is customized to suit the structure to be reinforced. Typically, mortar 50 is based on a matrix of hardenable paste, such as ductile concrete. Uncured ductile concrete may be termed a slurry, that is, a mixture of solid particles suspended in a liquid, with sufficient viscosity or surface tension that the particles remain suspended for a long time and yield a mixture that can be handled like a liquid or paste.
[0033] Ductile concrete is not typically used as a finish coat for homes, historical buildings, or other structures where appearance is important but a modern “industrial” look is not desired. However, it is a strong, ductile material that is less likely to crack under lateral forces than standard concrete.
[0034] Other matrix materials such as organic polymers or other inorganic cementitious materials may also be used to create mortar 50 .
[0035] Generally, building materials such as stone, brick, and adobe are not transported farther than necessary. As a result, structures in a given country or geographic area tend to have distinctive appearances. To customize mortar 50 , it is preferred that mineral materials are used that are similar to those used for the structure originally.
[0036] In the case of historical buildings, it is often desirable to determine the components of the original materials, such as by microscopic examination or chemical analysis.
[0037] For example, many older public buildings in the American Midwest are of the tan stone call Indiana limestone. In the American Southwest, many historical buildings are of adobe bricks, which vary in color depending upon the iron content of the local clay.
[0038] Thus, to reinforce a structure in the Midwest it might be appropriate to incorporate ground limestone into mortar 50 to produce a smooth tan surface on the reinforced structure. In the Southwest, adobe clay or ground sandstone might be added to mortar 50 to make it resemble brick or stone.
[0039] Mineral materials obtained locally may include sand, clay, gravel, ground stone, or mineral colorants. Although the minerals used for customized mortar finish coat 50 are described herein as locally obtained, it is to be understood that the mineral materials are to be obtained preferably from the same source as the materials of the original structure. For example, if an historical structure in Indonesia was built originally of imported Italian marble, it may be aesthetically desirable to obtain material from the same quarry in Italy to customize mortar 50 if reinforcing the structure in Indonesia.
[0040] An alternative embodiment of reinforcing system 10 is illustrated in FIGS. 3 and 4 . FIG. 3 is a top plan view of reinforcement system 10 , as used to strengthen an expansion joint 122 of a structure, such as a bridge 120 . FIG. 4 is a sectional view; taken on line 4 - 4 of expansion joint 122 of FIG. 3 .
[0041] Expansion joint 122 is a design feature of bridge 120 . It is a gap of a few inches width, left between sections of bridge 120 to allow for thermal expansion of the bridge material. The gap of expansion joint 122 is typically filled to provide a smooth surface for traffic.
[0042] The filling of expansion joint 122 must be of a material that is ductile and will not interfere with the function of expansion joint 122 . The alternative embodiment of reinforcing system 10 as illustrated in FIGS. 3 and 4 has been found to be a low cost and very effective way of dressing expansion joint 122 .
[0043] Expansion joint 122 has been created with a recess 125 to be filled to provide a smooth upper surface. To fill expansion joint 122 using system 10 of the present invention, a first layer of mortar 50 is laid into recess 125 , filling recess 125 approximately halfway. Next, a strip of textile 20 , as described above, is laid over mortar 50 . A second layer of mortar 50 is poured or spread over textile 20 to fill recess 125 to the desired level. Mortar 50 may be textured as desired or left in the as-applied state. Fiber anchors 30 are typically not required for this embodiment of system 10 .
[0044] It may be noted that reinforcement system 10 , as practiced for reinforcing structures such as buildings, may be optionally installed similarly to the method of filling expansion joints 122 . That is, a first layer of mortar 50 may be spread on the original wall 110 of the structure, then textile 20 attached over the first layer of mortar 50 . Fiber anchors 30 are preferably still employed as detailed above. Fiber anchors 30 are preferably installed after the first layer of mortar 50 . A second layer of mortar 50 is applied over textile 20 and fiber anchors 30 , then finished, also as described above.
[0045] This method of practicing the present invention is especially useful in the case of buildings that are constructed of fragile materials, or that have been weakened by weather, degradation by pollution, or earthquakes. Another precaution taken in the case of fragile buildings is to create a borehole for fiber anchor 30 that is deeper than is typically used for a strong matrix such as undamaged concrete.
[0046] Although particular embodiments of the invention have been illustrated and described, various changes may be made in the form, composition, construction, and arrangement of the parts herein without sacrificing any of its advantages. Therefore, it is to be understood that all matter herein is to be interpreted as illustrative and not in any limiting sense, and it is intended to cover in the appended claims such modifications as come within the true spirit and scope of the invention. | System and method for reinforcing structures includes basalt textile ( 20 ) connected to surfaces of the structure ( 100 ) with fiber anchors ( 30 ). Textile spreads forces and increases ductility of structure. Textile may connect multiple structural elements together, including walls, floors, columns, beams, and roofs. Textile is covered with mortar ( 50 ) customized to match color and texture of structure by use of locally obtained grit, aggregate, or colorant. Basalt fiber textile is preferred to avoid degradation of textile from alkaline components of mortar ( 50 ). | 4 |
CROSS-REFERENCE TO RELATED APPLICATIONS
The current application is a divisional application of U.S. application Ser. No. 11/721,835 (US2010/0004351), filed on Dec. 16, 2009 as a PCT national phase application of PCT/EP2005/013007 (WO2006/066725), which in turn claims the priority of EP Application No. 04293073.5 (EP1674434), filed on Dec. 21, 2004. The entire contents of these related applications are incorporated by reference into the current application.
TECHNICAL FIELD OF THE INVENTION
The present invention concerns the field of petroleum service and supply industries, in particular that of cementing the annulus surrounding the casing in an oil, gas, water, geothermal or analogous well. More precisely, the invention relates to cement slurry formulations which can prevent the passage of gas during the whole cement setting phase.
BACKGROUND OF THE INVENTION
A key objective in well cementing is to isolate the different formation layers traversed by the well to prevent migration between the different geological layers or between the layers and the surface. In particular, it is essential from the point of view of safety to prevent any gas from rising through the annulus between the well wall and the casing.
When the cement has set, it is impermeable to gas. Because of the hydraulic pressure of the height of the cement column, the injected slurry is also perfectly capable of preventing such migration. However, between the two states, there is a critical phase that lasts up to several hours during which the cement slurry no longer behaves as a liquid but also does not yet behave as an impermeable solid. For this reason, the industry has developed a series of additives aiming at maintaining a gas tight seal during the whole cement-setting period.
Among such (numerous) additives are those which also tend to reduce fluid loss, i.e., prevent dehydration of the petroleum industry fluid when the latter comes into contact with a natural porous or fissured formation. This loss of water can impair the proper placement of slurry in the annulus due to drastic increase in its rheological parameters; plastic viscosity and yield stress. In general, cement slurries with a fluid loss of less than 50 ml over thirty minutes, measured in accordance with API (American Petroleum Institute) standards, are also impermeable to gas, although the correlation between the two phenomena is not systematic, and other parameters such as the almost complete absence formation of free fluid (although known as free water) is also necessary, especially in a non vertical slanted well since the supernatant free fluid can create a path for the migration of gas.
The fluid loss is controlled by adding to the cement slurry either high molecular-weight water-soluble polymers or particulate additives such as latices or crosslinked polymers.
The efficiency of water-soluble polymers is generally limited because they cannot be used at high concentrations owing to too high slurry viscosities at the mixing stage. This may be a major limitation when the solid volume fraction of slurry is high (e.g. higher than 50%) and/or when the slurry is designed for elevated temperatures since fluid loss control provided by these polymers is primarily based on a thickening effect of the interstitial water of slurry.
Some latices provide excellent fluid-loss control (API value below 50 mL/30 min.) and, therefore, are frequently used for gas migration control. However rather high concentrations are required, making latices not cost effective when there is no risk for gas migration. It is believed that small latex particles (around 150 nm diameter) fill the pores of cement filter cake, and can coalesce to form an impermeable layer of polymer. It may be difficult to increase the plastic viscosity of latex cement slurries that generally are thin. In some cases it can be difficult to properly remove the drilling mud when the slurry viscosity is low.
Though the use of latices, such as natural rubber latex, in Portland cements was common since the 1920s, especially because of the improvements in mechanical performance, a key improvement occurred in 1985, when Parcevaux et al. identified styrene-butadiene latex an effective additive for preventing annular gas migration. This system is known for instance from European Patent 0 091 377 (or its counterpart U.S. Pat. No. 4,537,918) that more specifically discloses cement slurry compositions inhibiting pressure gas channeling in the cemented annulus, even at high temperature, consisting essentially of a hydraulic cement, about 5-30% by weight of cement of a compatible styrene (70-30 weight percent)/butadiene (30-70 weight percent) copolymer latex and about 1-20% by weight of latex of a latex stabilizer and water in an amount such that the total fluid content of water, latex and stabilizer is about 30-70% by weight of cement.
In an attempt to control gas channeling at lower cost, U.S. Pat. No. 5,099,922 (Ganguli) describes the use of a copolymer of 5 to 95 weight percent 2-acrylamido-2-methylpropane-3-sulphonic acid (AMPS); (2) 5 to 95 weight percent of vinylacrylamide; and (3) 0 to 80 weight percent of acrylamide. This copolymer may be used in combination with a gas channeling inhibiting amount of an experimental styrene/butadiene latex, wherein the styrene is substituted with at least one selected from the group consisting of —COOR, —SO 3 R, and —OH, wherein R is H or a C 1 -C 5 alkyl groups. However, there is no report of a synergetic effect of this combination and all tests were carried out at bottomhole temperature of 180° F. (82° C.).
Further, a cement slurry comprises in practice a whole series of additives, almost systematically among them an agent which encourages dispersion of the cement particles. The dispersing agents used vary depending on the type of wellbores or, more exactly, depending on the temperature to which the cement is subjected. Argillaceous minerals such as bentonite are also frequently used as they can reduce the density of the cement slurry, an essential point when cementing in zones where the formation pressure is low. The question of the compatibility of each new additive with current additives, over a wide range of working temperatures and pressures, is thus fundamental, it being understood that no additive is genuinely universal.
Therefore it would be suitable to provide new fluid loss control agents that could overcome some of the drawbacks of the prior art, in particular in terms of costs.
SUMMARY OF THE INVENTION
The authors of the present invention have found that the addition of a small amount of water-soluble polymer to (non-substituted) styrene-butadiene latices allows drastic reduction of the amount of latex required to achieve excellent fluid loss control.
Without wishing to be limited by any theory, this synergetic combination may be primarily attributed to both an increase in the viscosity of the interstitial water due to the part of polymer that is not adsorbed onto cement grains and a decrease in the pore size of cement filter cake due to the part of polymer that is adsorbed onto cement grains thanks to its sulfonate and carboxylate groups (when part of acrylamide is hydrolyzed into acrylate).
It is believed that the synergetic effect is achieved only with water-soluble polymers of relatively high molecular weight, such at higher than about 200,000 and preferably higher than 500,000. It is also believed that polymers having a molecular weight higher than about 4,000,000 are not suitable. Best results have been achieved with water-soluble polymers having a molecular weight of about 800,000 (typically between 600,000 and 1,200,000).
In yet a preferred embodiment, the water-soluble polymer is an anionic synthetic co- or ter-polymer derived from acrylamide (Am), most preferably containing a sulfonate monomer: 2-acrylamido 2-methylpropanesulfonic acid (AMPS).
The concentration of each component in the mixture is significantly lower than that of individual components when they are used separately. The mixture of latex and water-soluble polymer is effective as fluid-loss control additive over a wide temperature range. Contrary to what is observed with individual components, in terms of fluid-loss control, the performance is only slightly dependent upon the temperature (tested from 38° C. to 177° C.). Consequently elevated temperatures do not require much higher concentrations. Cement slurries containing this mixture have an appropriate rheology for proper mud removal and do not show any tendency for free fluid development.
The rheology of cement slurries designed with this mixture is intermediate between that corresponding to cement slurries designed with either the water-soluble polymer or the latex. This could enable better mud removal, notably in wide annuli when the cement slurry cannot be displaced in turbulent flow.
Most of cement slurries containing the latex/polymer mixture did not develop any free fluid, except in the presence of some retarders, which have strong dispersing properties, at elevated temperatures. Even in those cases the free fluid could easily be completely eliminated by adding small amounts of anti-settling agent. It is remembered that zero free fluid often is difficult to achieve.
A fluid loss control additive according to the present invention typically contains from about 4 wt % to about 8 wt % of water-soluble dry polymer by weight of dry latex suspension Since the latex is typically provided in a suspension in water with a latex content of about 45 wt % and the polymer in a water solution at 10 w %, a new fluid loss control additive with 6 wt % of water-soluble dry polymer by weight of dry latex can be prepared by adding 80 volume of latex suspension to 20 volume of polymer solution.
With this fluid loss control agent comprising 80 volume of latex suspension and 20 volume of polymer solution, excellent fluid loss controls are achieved with concentrations ranging from about 50 to about 200 liters per metric tonne of solid blend (typically cement or cement and silica flour at higher temperatures) or if calculated based on the dry latex content from about 20 kg to about 80 kg of dry latex per metric tonne of blend for temperatures ranging from about 30° C. to about 180° C.; with the higher amounts required for the higher bottomhole temperatures.
This corresponds to an optimal ratio not only with regard to fluid-loss control but also to cement slurry rheology (for proper mud removal when the slurry is displaced in laminar flow) and slurry stability (i.e. no free fluid). The two components can be added separately to cement slurries or can be blended together as a single additive.
BRIEF DESCRIPTION OF THE DRAWING
Other aspects and advantages of the invention will be apparent from the following description and the appended claims, with reference to the accompanying figures in which:
FIG. 1 represents a Cement Hydration Analyzer (CHA), the testing equipment used for evaluating the gas tightness of the cements and;
FIG. 2 is the flow chart of the tests results with the CHA equipment.
DETAILED DESCRIPTION
As mentioned above, the invention essentially consists in adding a relatively small amount of water-soluble polymers to latices, to achieve fluid-loss control with reduced quantities of additives.
The latex is preferably a styrene-butadiene copolymer having a styrene to butadiene weight ratio ranging from about 30:70 to about 70:30, and preferably from about 40:60 to about 60:40, suspended in an aqueous solution in the range of from about 40% to about 70% water by weight of the latex. The aqueous solution further includes a latex stabilizer, for instance a surfactant as it is well known in this art. An example of suitable latex suspension can be found in Parcevaux et al.
The water-soluble polymer is a high-molecular weight water-soluble polymer consisting of
(a) 1-99% by weight of structural units of the formula 1:
where R 1 is hydrogen or methyl, R 4 is C1-C22 alkylene, R 5 is C1-C22-alkyl or hydrogen, and X is ammonium, lithium, sodium, potassium, an amine or a mixture of these substances; and
(b) 99-1% by weight of structural units of the formula 2:
where R 1 is hydrogen or methyl, R2 and R3, independently of one another, are hydrogen or C1-C22-alkyl.
R2 and R3 are preferably hydrogen. R4 is preferably a C2-C10-alkylene, most preferably a C3-alkylene and R5 is preferably hydrogen or methyl. Yet according to a preferred embodiment, the copolymer is a copolymer of 2-acrylamido 2-methylpropanesulfonic acid (AMPS) and acrylamide (Am) [in other words R 1 , R 2 , R 3 , and R 5 are equal to H and R 4 is equal to —C(CH 3 ) 2 —CH 2 —].
The weight ratio of units of formula 1 is preferably from 50 to 80% by weight. In yet a further preferred embodiment, the polymer is a copolymer AMPS-AM comprising about 70% by weight of the ammonium salt of AMPS and 30% by weight of acrylamide.
The polymer synthesis may be carried out in aqueous solution, as disclosed for instance in U.S. Pat. No. 4,015,991. In this case, at least about 20% of the acrylamide units are hydrolyzed to acrylic acid. This initial hydrolization can be avoided when, according to a preferred embodiment of the present invention the copolymer is prepared by solution precipitation polymerization in a non-aqueous solvent, or a water-miscible, organic solvent having a low water content, as disclosed for instance in U.S. Pat. No. 6,277,900. Even though a non-hydrolyzed water-soluble polymer is preferred, it should be noted that some hydrolization occurs during the cementation process, the degree of hydrolization being enhanced by the high pH of the interstitial water in the cement slurry.
The performance of latex/polymer mixture was tested at different temperatures ranging from 38° C. (100° F.) to 177° C. (350° F.). Note that it is believed that the fluid loss performance will be maintained at temperatures lower than 38° C., though latices systems are usually not used at very low temperatures since alternative solutions are considered cheaper.
The cement slurries were prepared with different types of cement: a Black Label Dyckerhoff Class G and a Red Label Dyckerhoff Class G cement mixed with fresh water or ASTM seawater to a density of 1.89 g/cm 3 (15.8 lbm/gal also noted 15.8 ppg); a Class H cement, mixed with fresh water to a density of 1.96 g/cm 3 (16.4 lbm/gal); and a pozzolanic cement mixed with fresh water at 1.62 g/cm 3 (13.5 lbm/gal). Tap water was used except for the test with seawater.
Cement slurries designed for elevated temperatures contain 35% by weight of cement (BWOC) of silica flour to prevent the well-known “strength retrogression” effect experienced when the Bottom Hole Static Temperature (BHST) is above 110° C. (230° F.). This corresponds to lower Bottom Hole Circulating Temperatures (BHCT). In the absence of silica flour the compressive strength of the cement matrix is lower and its permeability is higher. These bad performances are due to the formation of alpha-dicalcium silicate hydrate. The addition of 35% BWOC silica flour leads to the formation of other high-temperature cement hydrates (e.g., tobermorite or xonotlite) with better mechanical properties.
An antifoam agent is systematically added to prevent excessive formation of foam during the mixing of cement slurry. A polysiloxane was used as antifoam agent in all tests.
A dispersant and a dispersant aid can be added to obtain properly dispersed slurries. Their presence is not always needed due to the dispersing effect of other additives, notably the retarders when they are used at high concentrations at elevated temperatures. Some slurry designs also require the addition of an anti-settling agent to avoid over-dispersion of slurry due to the retarder, resulting in the appearance of free fluid in some cases. In most cases, an aqueous solution of a salt of polynaphtalene sulfonate was used as dispersant.
Different retarders were used for the different tests, the choice of retarder being determined by the temperature of use. Retarder A is primarily an unrefined lignosulfonate solution, retarder B is an aqueous blend of lignin amine and sodium salt of organic acid, retarder C is based on a mixture of sodium gluconate and sodium silicate, retarder D is a purified lignosulfonate, retarder E is based on a mixture of organic and inorganic salt, retarder F is based on organic acid derivatives, and retarder G is based on a mixture of purified lignosulfonate and organic acids.
To be noted that when a concentration is given in liters per tonne, reference is made to a tonne of blend (cement or cement plus silica flour when present).
Unless otherwise noted, the tested water-soluble polymer was a copolymer AMPS-Am, that dry, corresponds to formula 3:
with y being equal to about 0.56 (corresponding to a weight ratio AMPS:Am of about 70:30) and X═NH 4 + . Its molecular weight was about 800,000. The polymer is provided in a solution containing 10.7 wt % of dry polymer, 4 w % of sodium chloride and 85.3% of water.
Two grades of SBR latex were used, depending on the temperature of use, that have slightly different styrene to butadiene ratio. The suspension contains about 45 w % dry latex.
When the latex suspension and the water-soluble polymer in solution are mixed together at a volume ratio of 80% latex suspension and 20% water-soluble polymer (which as explained before corresponds actually to a weight ratio of about 3% dry polymer per mass of latex suspension), the viscosity of the mixture is about 3000 mPa·s. It can be decreased significantly by dilution with small amounts of water (e.g., 1200 mPa·s with 15% water)—of course, in this later case, the concentration of added FLAC mixture needs to be adjusted.
API rheology is measured after conditioning the slurry for 20 minutes in an atmospheric consistometer at BHCT or 85° C. (185° F.) when the BHCT exceeds this temperature. The plastic viscosity (in mPa·s) and yield stress (in Pa) of slurry are calculated from the readings obtained at different shear rates corresponding to rotation speeds in the rheometer of 300, 200, 100, 60, 30, 6 and 3 RPM. The Bingham model is used.
The operating free fluid is measured at BHCT or 85° C. (185° F.) when the BHCT exceeds this temperature. The amount of collected free fluid at the top of cement slurry after two hours under static condition is given in mL per 250 mL of cement slurry.
The fluid-loss control is measured at the BHCT with a stirred fluid-loss cell. The time to reach the BHCT is the same as for the thickening time test (table 1). The fluid loss is measured under a differential pressure of 6.895 MPa (1000 psi) through a 325 mesh screen. The API value is calculated by multiplying by two the amount of collected filtrate after 30 minutes filtration.
The thickening time is measured in a pressurized consistometer rotating at 150 RPM. The schedules are reported in table 1. The thickening time value corresponds to the time to reach a slurry consistency of 100 Bearden units, corresponding to the beginning of cement set.
The development of compressive strength is followed using an Ultrasonic Cement Analyzer (UCA). The slurry is introduced right after mixing (i.e., without pre-conditioning period in an atmospheric consistometer) in the UCA cell pressurized at 20.68 MPa (3000 psi). The slurry is heated to BHCT at the same heating rate as for the thickening time tests (see table 1). Times to reach 0.34 MPa (50 psi) and 3.45 MPa (500 psi) compressive strength are reported in tables 4 to 7 as well as the compressive strength value reached after 24 hours curing.
Table 1 depicts the schedules for thickening time tests reported in the different examples below. In the fifth column, time to T/P corresponds to the time to reach the final temperature and pressure.
Final
Heating
Initial
Temper-
Initial
Final
Time
Rate
Temperature
ature
Pressure
Pressure
to T/P
(° C./
(° C.)
(° C.)
(psi-MPa)
(psi-MPa)
(min.)
min.)
27
38
500-3.45
2600-17.9
14
0.79
27
49
1000-6.89
5200-35.9
28
0.79
27
66
1250-8.61
7500-51.71
36
1.08
27
85
1500-10.34
10200-70.33
44
1.32
27
93
1750-12.07
13400-92.39
52
1.27
27
104
1750-12.07
13400-92.39
52
1.48
27
110
2000-13.79
16100-111.0
60
1.38
27
121
2000-13.79
16100-111.0
60
1.57
27
132
2000-13.79
16100-111.0
60
1.75
27
149
2000-13.79
16100-111.0
34
3.59
27
166
2000-13.79
22000-151.7
44
3.16
27
177
2000-13.79
22000-151.7
44
3.41
EXAMPLE 1
These tests were carried out with retarder C. All slurries were prepared with Black Label Dyckerhoff Class G cement, mixed at 1.89 g/cm 3 (15.8 ppg) density with freshwater.
Table 2 depicts the rheology and fluid loss performance, of 3 cement slurries. The fluid-loss control is considered as good when the API fluid-loss value is below 100 mL/30 min, and considered as excellent when the value is less than 50 mL/30 min. Slurries #1 and #2, according to the prior art contain only one fluid loss control agent, either a water-soluble polymer (test #1) or a styrene-butadiene latex suspension (test #2). Slurry #3, according to the present invention, on the other hand contains as fluid loss control agent (FLAC), a mixture of 80% (by volume) of the same styrene-butadiene latex as in test #2 and 20% (by volume) of the same water-soluble polymer as in test #1.
Results essentially similar to the results obtained in test #2 were obtained in test #3 although the latex concentration is about one third the concentration in test #3 (in test #3, the concentration of water-soluble polymer is 13.16 liters per metric tonne of cement blend and 52.64 liters of latex per metric tonne of cement blend). Moreover, this effect is obtained with a small amount of water-soluble polymer that, in itself, would not have provided any fluid loss control.
TABLE 2
Test
#1
#2
#3
BHCT (° C.)
121
121
121
Silica Flour (% BWOC)
35
35
35
Anti-settling Agent (% BWOC)
0.3
—
0.3
Antifoam Agent (L/tonne*)
1.97
1.97
1.97
Dispersant (L/tonne*)
—
3.29
—
Retarder C (L/tonne*)
9.86
9.21
9.86
New FLAC (L/tonne)
—
—
65.8
Water Soluble Polymer (L/tonne*)
32.9
—
—
Styrene-Butadiene Latex (L/tonne*)
—
164.4
—
Mixing Rheology:
Plastic Viscosity (mPa · s)
176
46
94
Yield Stress (Pa)
15.8
4.2
10.6
API Rheology at 85° C.:
Plastic Viscosity (mPa · s)
95
26
63
Yield Stress (Pa)
3.8
1.4
4.2
Free fluid at 85° C.
0
3
0
API Fluid Loss at 121° C.
72
34
44
Thickening Time at 121° C. (hr:min)
7:05
5:54
5:46
*tonne of blend (cement + silica flour)
Data reported in table 2 illustrate the fact that the plastic viscosity of the cement slurry containing the new FLAC is higher than that of the slurry designed with the latex and lower than that of the slurry designed with the water-soluble polymer. An “intermediate” slurry viscosity can be valuable in terms of proper mud removal.
The rheologies measured right after slurry mixing are also reported in table 2. It is generally recognized that severe mixing difficulties are encountered if the plastic viscosity at the mixing stage exceeds about 300 mPa·s. The plastic viscosity can increase sharply if the slurry porosity is decreased in order to raise the slurry density (i.e., water-reduced slurries) or to apply the multi-modal concept known for instance from European Patent 621,647. Consequently the new FLAC is particularly suitable for those slurries.
Despite the lower slurry viscosity it is noted that the fluid-loss control obtained with the new FLAC is significantly better than that provided by the water-soluble polymer. The latex, used alone, gives an excellent fluid-loss control but high concentrations are generally needed.
EXAMPLE 2
Data gathered in table 3 show the effect of the volume ratio of water-soluble polymer to latex suspension. To be noted that the measure of free fluid cannot be made at a temperature greater than 85° C. (185° F.), so whenever the BHCT is greater than 85° C., the test was actually carried out at this temperature and not the BHCT. All slurries were prepared with Black Label Dyckerhoff Class G cement, mixed at 1.89 g/cm 3 (15.8 ppg) density with freshwater.
TABLE 3 Test #4 #5 #6 #7 BHCT (° C.) 66 66 121 121 Silica Flour (% BWOC) — — 35 35 Antifoam Agent (L/tonne*) 2.66 2.66 1.97 1.97 Dispersant (L/tonne*) 4.66 4.66 2.63 2.63 Retarder A (L/tonne*) 0.89 0.89 — — Retarder B (L/tonne*) — — 6.58 6.58 Water Soluble Polymer (L/tonne*) 17.75 13.32 15.78 11.84 Styrene-Butadiene Latex (L/tonne*) 71.02 75.45 63.13 67.04 Latex suspension/Polymer solution 80/20 85/15 80/20 85/15 volume ratio Free fluid at 66° C. (or 85° C.) 0 Traces 0 Traces API Fluid Loss at BHCT 42 50 54 65 *tonne of blend (cement in tests #4 and #5 and cement + silica flour in tests #6 and #7)
An increase of the latex/polymer ratio leads to higher fluid loss, and appearance of free fluid, none of this characteristics being desirable.
EXAMPLE 3
Data gathered in table 4 show the effect of the type of chosen retarder in the formulation. The slurries were prepared with fresh water, with class G Black Label Dyckerhoff cement at 1.89 g/cm 3 (15.8 ppg) density. Except in tests #22 and #23, the fluid loss control agent (noted FLAC) is a mixture of 80% (by volume) of the same styrene-butadiene latex as in test #2 and 20% (by volume) of the same water -soluble polymer as in test #1.
Temperatures range from 49° C. to 177° C., determining the choice of retarder. Also when found suitable, an antisettling agent was added. To be noted that tests #22 and #23, performed at temperatures higher than 150° C. were carried out with a styrene-butadiene latex grade adapted to higher temperatures.
TABLE 4
Test
#8
#9
#10
#11
#12
#13
BHCT (° C.)
49
66
66
85
85
85
Antifoam Agent (L/tonne*)
2.66
2.66
2.66
2.66
2.66
2.66
Dispersant (L/tonne*)
3.55
4.44
4.44
4.44
4.44
4.44
Dispersant Aid (L/tonne*)
—
—
—
3.55
—
—
Retarder A (L/tonne*)
0.89
0.89
—
2.66
—
—
Retarder C (L/tonne*)
—
—
1.78
—
—
—
Retarder D (L/tonne*)
—
—
—
—
1.78
—
Retarder E (L/tonne*)
—
—
—
—
—
2.66
FLAC (L/tonne*)
70.9
88.8
88.8
88.8
88.8
88.8
API Rheology at BHCT:
Plastic Viscosity (mPa · s)
54
59
57
59
62
56
Yield Stress (Pa)
3.1
4.5
3.5
5.6
9.6
6.4
Free fluid at BHCT
0
0
0
0
0
0
API Fluid Loss at BHCT
60
42
51
54
50
61
Thickening Time at BHCT
3:29
4:39
6:42
6:21
5:19
6:09
Compressive Strength at BHCT:
Time to reach 50 psi (hr:min)
7:20
14:24
15:16
17:36
8:20
11:28
Time to reach 500 psi (hr:min)
8:52
15:48
16:28
19:32
10:04
13:00
Compressive at 24 hours (psi)
2455
1860
1915
1730
2120
2285
*tonne of cement
Test
#14
#15
#16
#17
#18
#19
BHCT (° C.)
93
93
104
121
121
121
Silica flour (% BWOC)
35
35
35
35
35
35
Antisettling agent (% BWOC)
—
—
0.3
—
—
Antifoam Agent (L/tonne*)
1.97
1.97
1.97
1.97
1.97
1.97
Dispersant (L/tonne*)
3.29
1.32
3.29
—
4.60
2.63
Dispersant Aid (L/tonne*)
—
1.97
3.29
—
—
—
Retarder B (L/tonne*)
—
—
—
—
—
6.58
Retarder C (L/tonne*)
1.97
—
—
9.86
—
—
Retarder D (L/tonne*)
—
2.63
—
—
—
—
Retarder F (L/tonne*)
—
—
2.63
—
7.23
—
FLAC (L/tonne*)
65.8
78.9
65.8
65.8
78.9
78.9
API Rheology at 85° C.:
Plastic Viscosity (mPa · s)
63
84
49
63
57
64
Yield Stress (Pa)
4.1
5.4
5.6
4.2
3.8
3.0
Free fluid at 85° C.
0
0
0
0
0
0
API Fluid Loss at BHCT
65
58
50
44
49
54
Thickening Time at BHCT
5:30
3:01
5:47
5:46
9:59
5:46
Compressive Strength at BHCT:
Time to reach 50 psi (hr:min)
9:00
8:36
6:56
5:10
6:48
6:04
Time to reach 500 psi (hr:min)
10:32
9:52
8:00
6:12
8:36
7:28
Compressive at 24 hours (psi)
2530
2400
2535
2665
2425
2245
*tonne of blend (cement + silica flour)
Test
#20
# 21
# 22
# 23
BHCT (° C.)
132
149
166
177
Silica flour (% BWOC)
35
35
35
35
Antisettling agent (% BWOC)
0.2
0.2
0.2
0.3
Antifoam Agent (L/tonne*)
1.97
1.97
1.97
1.97
Retarder B (L/tonne*)
9.86
16.44
16.44
17.75
Retarder G (L/tonne*)
—
9.86
16.44
17.75
FLAC (L/tonne*)
78.9
92.1
131.5
144.7
API Rheology at 85° C.:
Plastic Viscosity (mPa · s)
63
67
73
83
Yield Stress (Pa)
2.3
5.3
4.5
10.9
Free fluid at 85° C.
0
0
0
0
API Fluid Loss at BHCT
56
72
60
46
Thickening Time at BHCT
6:21
5:53
10:34
6:02
Compressive Strength at BHCT:
Time to reach 50 psi (hr:min)
5:16
13:40
21:20
8:04
Time to reach 500 psi (hr:min)
6:52
15:52
25:40
9:52
Compressive at 24 hours (psi)
1900
2170
310
1855
*tonne of blend (cement + silica flour)
The new FLAC can be used with different retarders and its performance does not appear to depend significantly on the chemistry of retarder. The thickening time can easily be adjusted with the retarder and the cement develops rapidly its compressive strength.
It is noted that excellent fluid-loss control is achieved at temperature of 66° C. (150° F.) and 85° C. (185° F.) when using 88.8 liters of the new fluid-loss control additive (FLAC) per tonne of cement. This concentration corresponds to 17.76 liters (20%) of water-soluble polymer and 71.04 liters (80%) of latex suspension. These concentrations would not allow obtaining good fluid-loss control if these two additives were not used together. Actually such level of fluid-loss control is somehow attributed to a synergy between the latex and the water-soluble polymer.
Cement slurries are properly dispersed (low yield stress) and plastic viscosity values are not very high (around 60 mPa·s) enabling an easy placement of slurry in long and narrow annuli. They do not develop any free fluid, property that is not always easy to achieve, especially when the free fluid is measured at BHCT (or 85° C.) and not at room temperature.
The thickening time can easily be adjusted with the retarder and the cement develops rapidly its compressive strength.
Data gathered in tables 4 also show that similar results are obtained at higher temperatures. These slurries contain 35% BWOC silica flour to prevent the “strength retrogression” effect that occurs when the curing temperature is above 110° C. (230° F.). The addition of silica flour results in slightly lower slurry porosity (i.e., volume of water-to-volume of slurry) if the slurry density is maintained constant at 1.89 g/cm 3 (15.8 ppg). So the concentration of FLAC was reduced accordingly. Nevertheless it is noted that excellent fluid-loss control could still be achieved at elevated temperatures. This feature is rather unusual because it is known that the concentration of fluid loss control agent, which are based on water-soluble polymers, has to be increased significantly when raising temperature. At temperatures higher than 150° C., higher concentrations are required but it remains that compared to standard fluid loss control agents, the fluid-loss control performance of the new FLAC is far less temperature sensitive.
At very high temperatures the addition of an anti-settling agent is generally required due to the dispersing effect of some retarders that have to be used at high concentrations to get long enough thickening times. Even in the presence of an anti-settling agent it is not always easy to obtain zero free fluid. Thus the new FLAC is particularly beneficial with regard to this important property.
EXAMPLE 4
In this series of tests, the class G cement was replaced by a coarser LeHigh Class H cement, mixed with fresh water at 1.97 g/cm 3 (16.4 ppg) density. The formulations, rheological properties and basic setting properties are gathered table 5.
Again, a wide range of temperatures was covered. As for example 3, with the highest temperatures (#28 and #29), a special grade of latex was used.
TABLE 5
Test
# 24
# 25
# 26
# 27
# 28
# 29
BHCT (° C.)
38
93
121
149
166
177
Silica Flour (% BWOC)
—
35
35
35
35
35
Antifoam Agent (L/tonne*)
2.66
1.97
1.97
1.97
1.97
1.97
Retarder E (L/tonne*)
—
6.58
—
—
—
—
Retarder B (L/tonne*)
—
—
7.89
15.12
17.10
18.41
Retarder G (L/tonne*)
—
—
—
15.12
17.10
18.41
FLAC (L/tonne*)
62.1
75.6
82.2
98.6
118.4
131.5
API Rheology at BHCT or 85° C.:
Plastic Viscosity (mPa · s)
88
133
154
123
113
128
Yield Stress (Pa)
7.9
9.0
5.5
8.3
8.1
7.6
Free Fluid at BHCT or 85° C.
0
0
0
0
0
0
API Fluid Loss at BHCT
50
53
57
50
59
41
Thickening Time at BHCT
3:19
4:35
5:40
5:27
10:00
6:22
Compressive Strength at BHCT:
Time to reach 50 psi (hr:min)
6:20
8:48
5:24
15:32
18:32
8:37
Time to reach 500 psi (hr:min)
8:48
10:40
6:36
18:20
20:26
10:15
Compressive at 24 hours (psi)
2750
2075
1715
1705
2020
1840
*tonne of blend (cement in test #24; and cement + silica flour in tests #25 to #29)
It is worth noting that the FLAC according to the present invention does not have a retarding effect at low temperature (38° C.), so that the addition of an accelerator was not required. This is indeed advantageous since any addition of an accelerator may be detrimental to some of the slurry properties (e.g. fluid loss control and rheology) and make designing the slurry more complex. Plastic viscosities in this series of tests were higher due to lower slurry porosities.
EXAMPLE 5
This series of tests was carried out to check that it was possible to use the fluid loss control agent according to the present invention with seawater as mixing fluid, as it is sometimes the case in offshore applications.
All slurries of table 6 were prepared with Red Label Dyckerhoff Class G cement, mixed with ASTM seawater at 1.89 g/cm 3 (15.8 ppg) density. The slurry porosity was equal to 60.7% for tests #30 and #31, where no silica flour was added and to 57.2% for tests #32 and #33 where 35% BWOC silica flour was added.
TABLE 6
Test
# 30
# 31
# 32
# 33
BHCT (° C.)
49
85
110
132
Silica Flour (% BWOC)
—
—
35
35
Antifoam Agent (L/tonne*)
2.66
2.66
1.97
1.97
Dispersant (L/tonne*)
15.09
15.09
9.86
—
Dispersant Aid (L/tonne*)
—
2.66
—
—
Retarder A (L/tonne*)
1.33
—
—
—
Retarder D (L/tonne*)
—
3.55
—
—
Retarder B (L/tonne*)
—
—
6.58
13.15
Retarder G (L/tonne*)
—
—
—
13.15
FLAC (L/tonne*)
97.6
111.0
92.1
98.6
API Rheology at BHCT or 85° C.:
Plastic Viscosity (mPa · s)
76
51
106
48
Yield Stress (Pa)
3.6
5.5
7.4
2.4
Free Fluid at BHCT or 85° C.
0
0
0
0
API Fluid Loss at BHCT
61
58
51
61
Thickening Time at BHCT
6:29
6:14
6:47
8:57
Compressive Strength at BHCT:
Time to reach 50 psi (hr:min)
13:24
18:48
10:20
35:56
Time to reach 500 psi (hr:min)
15:12
21:32
11:36
39:04
Compressive at 24 hours (psi)
2605
1130
2160
—
*tonne of blend (cement in tests #30 and #31; and cement + silica flour in tests #32 and #33)
Table 6 shows that the new FLAC is compatible with seawater, though higher FLAC concentrations are required to achieve a good fluid loss, as it is often observed with other fluid loss control agents when seawater is used.
EXAMPLE 6
The new fluid loss control agent is also compatible with lightweight cement such as the TXI lightweight cement (a fine pozzolanic cement with a specific gravity of 2.84, compared to about 3.23 for Class G and Class H cements). The slurries of table 7 were mixed with fresh water at 1.62 g/cm 3 (13.5 ppg) density, with a slurry porosity of 66.8%. Since the TXI lightweight cement has a CaO-to-SiO2 ratio much lower than that of Class G and Class H cements, no silica flour was added at elevated temperatures.
TABLE 7
Test
# 34
# 35
# 36
BHCT (° C.)
49
85
110
Antifoam Agent (L/tonne)
4.44
4.44
4.44
Dispersant (L/tonne)
8.88
13.32
8.88
Dispersant Aid (L/tonne)
—
—
4.44
Retarder A (L/tonne)
4.44
—
—
Retarder E (L/tonne)
—
7.10
—
Retarder B (L/tonne)
—
—
11.54
FLAC (L/tonne)
124.3
142.0
150.9
API Rheology at BHCT or 85° C.:
Plastic Viscosity (mPa · s)
57
46
49
Yield Stress (Pa)
5.2
3.8
5.5
Free Fluid at BHCT or 85° C.
0
0
0
API Fluid Loss at BHCT
54
58
54
Thickening Time at BHCT
4:47
4:37
4:49
Compressive Strength at BHCT:
Time to reach 50 psi (hr:min)
9:08
12:44
7:44
Time to reach 500 psi (hr:min)
13:00
14:52
8:24
Compressive at 24 hours (psi)
1275
2115
1795
These tests show that the new fluid loss control agent can indeed be used with this type of system. However, higher concentrations are required because of the higher porosity. It should be noted that in general, latex systems do not work properly and are not considered cost effective when the slurry porosity is higher than 63%
EXAMPLE 7
A gas migration test was performed using the Cement Hydration Analyzer (CHA) schematized in FIG. 1 . This equipment essentially consists of a cylindrical cell 1, filled with the cement slurry and pressurized with a piston 2 located at the bottom. The pore pressure of cement slurry is measured with the pressure sensor 3. Water can be supplied through a water supply 4 to maintain a constant pressure during the test. The equipment further comprises a gas source 5 (N 2 for testing purpose) so that gas can be injected into the slurry through pipe 6.
Initially, the slurry is poured into the cell and a pressure of 2.49 MPa is applied through the piston. While keeping this pressure constant, the pore pressure is monitored. With the beginning of the cement setting, the pore pressure, initially identical to the piston pressure, starts to decrease. When it reaches 1.75 MPa, nitrogen is injected.
If the cement slurry is gas tight, the decrease of the pore pressure goes on. However, if the cement is permeable, the pore pressure raises again after a gap period that reflects the time required for the gas to migrate through the whole cement column.
A slurry was prepared with fresh water, Black Label Dyckerhoff Class G cement with 35% BWOC silica flour. It further contains 1.97 L/tonne of blend (silica flour+cement) of an antifoam agent, 1.32 L/tonne of blend of a dispersing agent, 0.97 L/tonne of blend of retarder D and 78.9 L/tonne of blend of the new fluid loss control agent according to the present invention. The slurry density is 1.89 g/cm3 (15.8 ppg).
The test is carried out at 93° C. As shown in FIG. 2 , once the injection of the gas starts, the pore pressure continues to decrease until it reaches zero after complete setting of the cement, so that the cement is effectively considered gas tight. | A method of cementing a well is disclosed. The method comprising pumping into the well a cement slurry comprising a solid blend including cement, water, and a fluid loss control agent, and allowing the cement slurry to set. The fluid loss control agent comprises a styrene-butadiene latex and a high molecular-weight water-soluble polymer such as a copolymer AMPS-Am. The addition of the water-soluble polymer allows drastic reduction of the quantity of latex required to achieve fluid loss control performance and even gas migration control. | 2 |
[0001] This application is a continuation of U.S. patent application Ser. No. 09/770,827 filed on Jan. 26, 2001
FIELD OF THE INVENTION
[0002] The present invention relates to identification and access systems. More particularly it relates to vehicle identifications and access systems to allow entry into a secure area.
BACKGROUND OF THE INVENTION
[0003] There is a general need for vehicle identification systems for a multitude of applications such as controlling vehicular access in and out of parking structures, monitoring vehicular movement from one location to another, collecting tolls such as that found on the California toll road system, and restricting vehicular access to gated communities. Generally, systems such as AMTEK (used on the toll roads) or others are subject to malfunction due to RF noise interference, improperly installed equipment, or other factors that can prevent the vehicular identification transceiver from properly identifying the vehicle tag. The vehicle tag generally is a transponder that responds to a signal from the identification transceiver. Identification occurs when the vehicle is detected within a zone of detection.
[0004] When used to restrict access to a gated community or other limited access area the identification transceiver is located at and controls a gate opening and closing mechanism at an entry point into the restricted access area. The transceiver is connected to a vehicle detection system that, when operating properly, upon sensing the presence of a vehicle within a zone of detection in the area around the gate prompts the transceiver to broadcast a signal. Upon receipt of this broadcast signal by the transponder unit on the vehicle the transponder generates and broadcasts an encoded signal. Upon receipt by the transceiver of the encoded signal and identifying it as a valid code the transceiver authorizes the opening of the gate to allow entry of the vehicle into the restricted access area. However, as noted above these systems can malfunction for a variety of reasons including radio frequency interference, poor installation etc. Thus, many systems have to provide for a backup such as a live guard at the gated entry point to over-ride the system in the event it malfunctions. In the event there is no backup provision, the vehicle is forced to exit the entry point and retry to enter to re-trigger the system in an attempt to force the system to function properly. If this tactic fails the only option left is usually to call for assistance or forego entry if such assistance is not available and a 24 hour guard is not present.
[0005] Consequently, there exists a need for a system that can, provide for error free vehicle identification without relying on either a 24 hour guard system or other cumbersome and costly backup system. An identification and entry system that can be easily integrated into existing systems without the need for undue expense and modification of these systems.
SUMMARY
[0006] Thus, it is an objective of the present invention to provide an economical, easily used and effective process and system that will provide for error free vehicle identification and that will include the ability to quickly, easily and economically allow for correction of errors in the operation of the identification system. It is a further object to provide an error corrections system that is easy to manufacture and integrate into existing systems without undue cost and expense.
[0007] The present invention accomplishes these and other objectives by providing a secure area entry system that includes a) a movable barrier; b) an active detection device that controls the opening and closing of said entry barrier; c) a transponder which when detected by said active detection device within a zone of detection opens said barrier to allow access; and d) wherein said transponder has a manual override apparatus which upon activation sends a signal to the active detection device to open said barrier so that when said active detection device fails to detect the presence of said transponder in said zone of detection said barrier can be opened by sending the signal with said manual override apparatus. In another aspect of the system it provides a transponder with a button on it such that when the button is depressed said transponder broadcasts the signal to the active detection device.
[0008] In another aspect of the invention it provides a method for overriding a malfunctioning secure area entry system, that includes the steps of: a) detecting a vehicle at a limited access area entry port; b) generating an interrogation signal; c) generating an identification signal by the vehicle upon receipt of the interrogation signal; d) analyzing the identification signal to determine if it has a code that allows the vehicle to have access to the limited access area; and e) allowing a person in the vehicle to resend the identification signal if the vehicle does not obtain access to thereby reinitiate the step of analyzing the identification signal to determine if it has a code that will allow the vehicle to have access to the limited access area.
BRIEF DESCRIPTION OF THE DRAWINGS
[0009] The invention will be better understood by an examination of the following description, together with the accompanying drawings, in which:
[0010] FIG. 1 is a perspective view of one environment in which the present invention will work;
[0011] FIG. 2 is a schematic view of the major components of the system of the present invention in the environment in which they will function;
[0012] FIG. 3 is a side view of a transponder that incorporates the present invention;
[0013] FIG. 4 is a top view of the transponder depicted in FIG. 3 ;
[0014] FIG. 5 is a schematic block diagram of the major functional components of a transponder incorporating a preferred embodiment of the present invention;
[0015] FIG. 6 is a schematic block diagram of the major functional components of the transceiver interrogator detection device and gate opening mechanism; and
[0016] FIG. 7 is a flow chart of the operation of the present invention in the context of an automated system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0017] The present invention works with the typical vehicle detection systems used in gated communities. Such systems are designed to automatically determine when a vehicle at a gated entrance into the community is authorized to enter the restricted access area and open the gate to allow the vehicle to enter. FIG. 1 provides a prospective view of the major components of the system. A vehicle 21 upon reaching an entrance gate 23 of a gated community moves into the range of detection of a sensor 25 . The sensor 25 , in this case, is embedded in roadway 27 . The sensor 25 connects through appropriate circuitry to a transceiver interrogator unit 29 . Thus, when a vehicle 21 moves into rage of sensor 25 located under the road 27 it generates a signal that activates the transceiver interrogator unit 29 that in turn broadcasts a radio frequency signal 30 . Radio frequency signal 30 is received by a transponder 31 located on vehicle 21 , generally on the windshield 26 of the vehicle. Upon receipt of the signal generated by transceiver interrogator unit 29 , transponder 31 generates its own encoded radio frequency signal 32 that is received by the transceiver interrogator 29 . The transceiver interrogator unit 29 has appropriate circuitry to process the signal 32 received from transponder 31 and determine if the signal 32 from transponder 31 has a code of a vehicle authorized to enter the restricted area. If the transceiver interrogator unit 29 determines that it has received a code of an authorized vehicle it then signals a gate opening mechanism to open the gate 23 and allow the vehicle 21 to enter.
[0018] FIG. 2 provides an overhead schematic diagram of the system described above. FIG. 2 also depicts an alternative detection device, a laser beam generator 35 and receiver 37 . The laser detections system works such that when a vehicle 21 arrives at gate 23 and moves to a position in front of the closed gate it blocks transmission of laser beam 39 from laser 35 to receiver 37 which in turn prompts transceiver 29 to generate its activation signal 30 that in turn is received by transponder 31 . Transponder 31 generates its signal in response and as noted if upon receipt transceiver interrogator unit 29 determines it has received a correct authorization code it initiates opening of the movable portion 38 of the gate 23 . In addition to the vehicle loop detector 25 and optical beam 35 and 37 mentioned above any other proximity sensor capable of detecting a vehicle can be used. The RF signals exchanged between the transceiver and transponder can be simple ‘continuous wave’ (CW) or modulated signals.
[0019] The systems described above have a tendency to malfunction for a variety of reasons. The detection loop systems 25 quite often detect the presence of the vehicle 25 by the changes in the local magnetic field created by the presence of a vehicle directly over it. However, if some other metal structure is in the area or some other cause exists to change the nature of the local magnetic field, detection system 25 may not function properly and thus not properly activate transceiver interrogator unit 29 . Additionally, there may be some type of transient or permanent radio frequency interference in the local area that causes the system to malfunction. Such interference can be with the detection unit or interference with transmissions between the transceiver interrogator and transponder. When the system malfunctions and a vehicle carrying a transponder does not trigger the system properly the driver often has to back up and re-approach the gate in attempt to properly trigger the system. If this does not work then he or she is unable to enter unless there is someone present to open the gate for him. Most gated communities as a solution to this problem usually have a 24 hour guard located at one of the entries into the community who can initiate opening of the gate.
[0020] The present invention overcomes the problems of the current art by providing an override mechanism in the transponder unit that will allow the driver of a vehicle to initiate generation of the coded signal by the transponder. Thus, when the vehicle detection system malfunctions and the transceiver interrogator does not generate a signal to trigger the transponder, the driver can use the over ride system to do it. FIGS. 3 and 4 provide a side view and a top view respectively of a transponder unit 41 that includes the override mechanism of the present invention. The transponder unit 41 depicted in FIG. 3 and FIG. 4 typically has very compact dimensions of approximately three quarters of an inch thick by about three to three and a half inches long and a little over two to two and a third inches wide. The transponder 41 in a preferred embodiment depicted in FIG. 3 attaches to the windshield of a vehicle with adhesive strips 45 . Generally the transponder is positioned in the lower left or right corner of the windshield or ideally on front windshield behind the review mirror of the vehicle at which position it is out of sight but easily accessible.
[0021] The actual override mechanism consists of a button 47 that upon depression prompts transponder 41 to transmit access signal 32 mentioned above and illustrated in FIGS. 1 and 2 . Thus, when a driver of a vehicle arrives at the front gate of a gated community and for some reason the vehicle presence detection system as mentioned above fails to detect the presence of the vehicle and prompt transceiver interrogator unit 29 to generate a signal to interrogate transponder 41 the driver simply has to reach over to transponder 41 depress button 47 whereupon transponder 41 generates and transmits the necessary signal. The signal 32 is then detected by transceiver interrogator unit 29 , which upon identifying the signal as one from an authorized vehicle by confirming it has a valid access code sends a gate open signal to the gate opening mechanism 36 ( FIG. 2 ) to open the movable portion 38 of gate 23 and allow the vehicle to enter.
[0022] Naturally, transponder 41 has appropriate micro-circuitry and related electronic devices to function as described. Among the components as depicted in schematic diagram FIG. 5 transponder 41 typically would have are its own transceiver unit 49 , a stand alone micro power supply 51 , memory 52 of some kind to store the access code and any other programming the unit may need to function, circuitry 53 to appropriately interconnect the functional parts as well as override button 47 . Naturally, additional components could or may be added and a wide variety of different configurations could be used and the same result achieved.
[0023] At a minimum transceiver interrogator unit 29 , detection unit 25 and the gate opening mechanism will include the functional parts depicted in FIG. 6 . These consist of a transceiver 62 a CPU with memory 64 , a power supply 66 , a detection unit 68 , the gate operating mechanism 70 and circuitry 72 to appropriately interconnect all of these devices to properly function together. These are only the basic units necessary and any number of different configurations can be used without departing from the spirit of the present invention.
[0024] Radio frequency interference can also interfere with the radio signals exchanged between the transceiver interrogator and the transponder. In such situations even though the detector may properly detect the vehicle and send the appropriate activation signal because of radio frequency interference the system still might not determine the vehicle has the appropriate authorization code and admit the vehicle. In these situations the override button will allow the driver of the vehicle to resend the encoded signal and thus successfully open the gate without having to back up and drive forward to trigger the detection mechanism again.
[0025] FIG. 7 provides a flow chart of a preferred method or process of the system that incorporates the present invention. If the entry system is functioning properly upon the approach of a vehicle and its entry into the detection area of the detection device the vehicle is detected 81 . Upon detecting the vehicle 82 the detection unit signals the transceiver interrogator to generate an activation signal 83 . The transceiver interrogator then broadcasts an activation signal 84 . The activation signal is received by the transponder on the vehicle 85 . The transponder then broadcasts the encoded signal 86 . The encoded signal is received by the transceiver interrogator and if successfully decoded 87 the vehicle is identified 88 . Finally, the gate opening mechanism once activated by a gate open signal allows the vehicle to have access to the restricted area 89 . As note above sometimes the detection device does not detect the presence of the vehicle 82 and if this is the case the vehicle operator can push the override button 90 on the transponder which in turn prompts the transponder to broadcast the encoded signal 86 . If the encoded signal is successfully received and decoded at step 87 and 88 step 89 follows with the gate opening.
[0026] Additionally, if at step 87 the encoded signal is not received properly, the vehicle operator can push the override button and again initiate the final sequence of steps 86 , 87 , 88 and 89 . Also, if the signal is received but the code has some how become scrambled due to radio frequency interference or for some other reason and it is not been properly identified at step 88 then the vehicle operator can push override button 90 to initiate the final steps of 86 , 87 , 88 and 89 . Thus, the override button gives the vehicle operator control over the gate opening system to the extent that he or she can easily override the automated system when it fails to operate properly, and without undue effort or frustration assist the system in overcoming the difficulties it is experiencing. These problems as noted above can be from a variety of sources.
[0027] Those of ordinary skill in the art, once they have perused this specification and understand the concepts of the present invention should be able to practice the concepts of the present invention and implement it without undue experimentation. Although the preferred embodiment of the present invention discuss use of the invention is a system used to allow entry of motor vehicles, such as cars, trucks etc. the system can easily be extended to other secure area entry systems that rely on a similar system.
[0028] While the invention has been particularly shown and described with reference to a preferred embodiment thereof, it will be understood by those skilled in the art that various changes in form and detail may be made to it without departing from the spirit and scope of the invention. | A manual override device is disclosed for use with an automatic transponder system. This system has the capability of detecting errors in the operation of the system, and then for allowing for a manual override to initiate operation of a security gate when such is necessary. | 4 |
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims priority under 37 CFR 35 U.S.C. §120 to U.S. Provisional Patent Application Ser. No. 62/009,895 filed on Jun. 9, 2014, the contents of which are incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The following relates to methods and devices for reducing drag on rearward facing mirrors, their mirror housings or rearward viewing devices and their housings.
BACKGROUND OF THE INVENTION
[0003] Current proposed shapes for rearward-facing mirrors or rearward-facing devices address the leading edge of the housing to reduce aerodynamic or hydrodynamic drag. As a result these shapes do not address the drag created by the space of the mirror or mirror housing or rearward-facing device's reflective surface of a mirror or rearward-facing device's field of view.
[0004] There have been previous attempts to generally address the issue of drag created by mirrors and mirror housings, but the inventor is aware of no previous solutions for rearward-viewing devices or for forward- or rearward-viewing hydrodynamic viewing devices.
[0005] What each of these prior art approaches has in common is they are addressing the aerodynamic drag created by a mirror by creating a leading edge fairing to house the mirror or rearward-viewing device. However, none of these approaches address the drag created in the aft section of a mirror or mirror housing or rearward-facing device.
SUMMARY OF THE INVENTION
[0006] To the knowledge of the inventor, there are no prior design approaches directed to reducing drag on forward- or rearward-viewing devices. However, the inventor has identified an opportunity to address the drag created by a mirror, mirror housing, rearward- or forward-viewing device by addressing the aft section of a mirror, mirror housing, rearward- or forward-viewing device. The configurations provided herein are effective at reducing the drag of a mirror, mirror housing, rearward- or forward-viewing device applicable to all vehicles, and are straightforward to implement.
[0007] The unique configuration provided herein addresses the drag created in the aft section of the mirror, mirror housing, rearward- or forward-viewing device by providing one or more surfaces of equal or unequal length in a closed or open configuration in the aft section for the flow to pass along thereby reducing the drag of the mirror, mirror housing, rearward or forward viewing device. Where the surfaces are positioned to pass between the intended observer of the mirror (such as the driver of the vehicle) and the mirror itself, and/or to pass between objects intended to be viewed by the observer via reflection in the mirror (objects to be appearing in the mirror to the observer, such as vehicles behind the vehicle with the subject mirror), the surfaces are at least partly constructed of a material that can be seen through, such as plexi-glass or other transparent or nearly-transparent material. By providing a transparent or nearly-transparent material for producing the drag reducing structures, drag reduction can be provided without a problematic impact on visibility provided by the mirror.
[0008] Known types of drag reduction methods can be used in conjunction with the invention disclosed herein to reduce the overall drag of the mirror, mirror housing, rearward or forward viewing device.
[0009] The general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new drag reduction configuration which has many novel features that result in a reduction of drag which is not anticipated, rendered obvious, suggested or even implied by any of the prior design methods known to the inventor, either alone or in combination thereof.
[0010] The invention discussed in this document offers a means to reduce the drag of a rearward- facing mirror, mirror housing, rearward- or forward-viewing devices. The method includes reducing the drag of a mirror, mirror housing, rearward- or forward-viewing devices by adding an extension aft of the mirror, mirror housing, rearward- or forward-viewing device by providing one or more aerodynamic or hydrodynamic surfaces for the flow to travel along and thereby reduce the drag aft the mirror, mirror housing, or rearward- or forward-viewing device.
[0011] In accordance with an aspect there is provided a method for reducing the drag of a vehicle having a rearward-facing mirror or rearward- or forward- viewing device by increasing the length such device's housing with a trailing edge consisting of a closed housing in clear material that forms an aerodynamic tail, thereby significantly reducing the aerodynamic drag of said devices.
[0012] In accordance with another aspect there is provided an external mirror system for a vehicle comprising a mirror housing supporting a rearward-facing mirror having an exterior surface forming a leading edge forward of the mirror; and a transparent enclosure aligned with and extending continuously rearward with respect to the mirror from the exterior surface of the mirror housing to a substantially-narrowed trailing edge, and wherein the mirror is viewable through the transparent enclosure from within the vehicle.
[0013] In accordance with another aspect there is provided an external mirror system for a vehicle comprising a mirror housing supporting a rearward-facing mirror having a continuous exterior surface forming a leading edge forward of the mirror and a substantially narrowed trailing edge rearward of the mirror, wherein at least a portion of the mirror housing is transparent in order to permit viewing the mirror from within the vehicle.
[0014] In accordance with another aspect there is provided an external mirror system for a vehicle comprising a mirror housing supporting a rearward-facing mirror having an airfoil shape with a forward- and rearward-edge of the mirror housing with at least a portion of the mirror housing being transparent to permit viewing of the mirror from within the vehicle.
[0015] In accordance with another aspect there is provided a method for reducing the drag of a vehicle having a rearward-facing mirror, mirror housing or rearward- or forward-viewing device by increasing the length of a rearward-facing mirror, mirror housing or rearward- or forward-facing device's housing with a trailing edge whereby this extension forms a single-sided extension of the mirror or rearward-viewing device housing where the extension reflected in the mirror surface or rearward-facing device may or may not be clear and extends into the field of view of a mirror or rearward-facing device and this trailing edge forms an aerodynamic or hydrodynamic surface for a rearward-facing mirror or rearward-view device's rear edge, where the flow separated by the leading edge flows along this surface thereby reducing the aerodynamic drag of a mirror or rearward-viewing device.
[0016] In accordance with another aspect there is provided a method for reducing the drag of a vehicle having a rearward-facing mirror, mirror housing, rearward- or forward-viewing device by increasing the length of a rearward-facing mirror, mirror housing or rearward- or forward-facing device's housing with two or more trailing edges whereby this extension forms an open ended extension of the mirror, mirror housing or rearward-viewing device housing where the extension reflected in the mirror surface or rearward-facing device may or may not be clear and extends into the field of view of a mirror, rearward or forward-viewing device and these trailing edges form one or more aerodynamic or hydrodynamic surfaces for a rearward-facing mirror, mirror housing, rearward- or forward-viewing device's rear edge(s), where the flow separated by the leading edge follows these surfaces thereby reducing the aerodynamic drag of a mirror, mirror housing, forward- or rearward- viewing device's housing or device.
[0017] In accordance with another aspect there is provided an external camera system for a vehicle comprising a camera housing supporting a rearward-facing camera having an exterior surface forming a leading edge forward of the camera; and a transparent enclosure aligned with and extending continuously rearward with respect to the camera from the exterior surface of the mirror housing to a substantially-narrowed trailing edge, and wherein the camera has a field of view looking through the transparent enclosure.
[0018] In accordance with another aspect there is provided an external camera system for a vehicle comprising a camera housing supporting a rearward-facing camera having a continuous exterior surface forming a leading edge forward of the camera and a substantially narrowed trailing edge rearward of the camera, wherein at least a portion of the camera housing is transparent in order to permit the camera to have a field of view looking rearward of the vehicle through the transparent portion of the camera housing.
[0019] In accordance with another aspect there is provided an external camera system for a vehicle comprising a camera housing supporting a rearward-facing camera having an airfoil shape with a forward- and rearward-edge of the camera housing with at least a portion of the camera housing being transparent to permit the camera to have a field of view looking rearward of the vehicle through the transparent portion.
[0020] Other aspects and various advantages are disclosed herein.
BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Embodiments will now be described with reference to the appended drawing in which: each component of the mirror system is labelled with the following numbers corresponding to the part; 1 =mirror, 2 =mirror housing, 3 =mirror tail, 4 =vehicle, 5 =inside door panel of vehicle, 6 =representation of air flow, 7 =mounting screws, 8 =marker lights, 9 =camera lens, 10 =camera housing.
[0022] FIG. 1 is a side view illustrating horizontal airflow about an un-faired mirror during forward movement;
[0023] FIG. 2 is a rear-facing view illustrating horizontal application during forward movement about a mirror that has been faired according to an embodiment;
[0024] FIG. 3 is a front view illustrating airflow during forward movement about a mirror that has been faired according to an embodiment;
[0025] FIG. 4 is an isometric view illustrating airflow during forward movement about a mirror that has been faired according to an embodiment;
[0026] FIG. 5 is a top view illustrating airflow during forward movement about a mirror that has been faired according to an embodiment;
[0027] FIG. 6 is an isometric view illustrating airflow during forward movement about a mirror that has been faired according to an alternative embodiment; and
[0028] FIG. 7 is a front view of an alternative embodiment showing a side-mounted camera tail application in which a housing houses a rear-viewing camera and a marker light, the rear-viewing camera electronically communicating with a display screen (not shown) for displaying the objects within the field of view of the rear-viewing camera.
DETAILED DESCRIPTION
[0029] The detailed description set forth below in connection with the appended drawings is intended as a description of presently preferred embodiments of the invention and is not intended to represent the only forms in which the present invention may be constructed and/or utilized. The description sets forth the functions and the sequence of steps for constructing and operating the invention in connection with the illustrated embodiments. However, it is to be understood that the same or equivalent functions and sequences may be accomplished by different embodiments that are also intended to be encompassed within the invention.
[0030] Drag analysis of existing mirrors, mirror housings or rearward-facing devices as demonstrated in this video on a wind-tunnel dynamometer and therein represented by a disk, measures the amount of drag as measured on the wind-tunnel dynamometer at 05:09 minutes in this video https://www.youtube.com/watch?v= 4 q 5 ffroIMMc This particular segment clearly illustrates the measured drag of a mirror housing lacking a mirror tail by not addressing the aft section of the mirror. The overall drag of the mirror (represented by the disk) with a leading edge cowling and aft section tail further measures the overall drag reduction of the mirror tail as represented by the streamlined attachment to the wind tunnel dynamometer thereby demonstrating the aerodynamic efficiency achieved by a tail being applied to a surface that is perpendicular to air flow as demonstrated in the video at 05:27 minutes. Calculations in this video show a potential for drag reductions of a tail fairing to be 50-55% compared to a leading edge fairing alone. These aerodynamic test results corroborate the base drag reduction of a tail fairing applied to a surface that is perpendicular to air flow over a flat surface with a leading-edge fairing. This result is extremely important because it demonstrates that the addition of a tail section greatly reduces drag and improves efficiency of a mirror, mirror housing, rearward- or forward-viewing device compared to a such a with only a leading-edge fairing. This result improves the overall aerodynamic efficiency of an un-faired surface perpendicular to the air flow by 95% compared to an un-faired surface, as demonstrated at 05:50 minutes in this video.
[0031] For rearward facing mirrors whose surface is generally perpendicular to the air flow are (represented in this video at 04:57 minutes) a tail fairing or wing greatly reduces aerodynamic drag (shown in the video at 05:27 seconds). The trend is presented in FIGS. 2 , 3 , 4 , 5 , 6 which show that overall drag reduction achieved by applying a tail fairing to a flat or leading-edge surface.
[0032] This drag reduction is a result of reducing the vortices created by a surface that is perpendicular to the flow even if the leading edge of said surface is faired with a trailing edge. The vortices created by the difference in pressure by the lack of tail fairing are caused by the air vacating the area of relatively high pressure created behind the mirror as a result of the relatively low pressure created by the flow past this still air or fluid and this perpendicular motion of the air shedding swirling vortices increasing aerodynamic drag. This shedding of vortices at first appears random, but in reality the outward motion of the air on the opposite side of the incoming air creates a wave or wake that is repeated on the other side when the air pressure on the exiting air becomes equal to the surrounding air thus creating an area of low pressure on the other side; this repetitive vortex shedding on opposite sides of the perpendicular surface creates a oscillating wave that results in drag. This vortex shedding and repetitive wave is graphically illustrated in FIG. 1 . This vortex shedding and resulting wave is because the high-speed external flow “pulls” air out of the still air trapped behind the surface perpendicular to the flow according to Bernoulli principles. These two effects cause the air to be “pumped” away from the still air in the space behind the surface that is relatively perpendicular to the flow. Increased pressure behind the surface that is perpendicular to the flow results in this vortex shedding pumping action and repeating pumping action will continue the resulting drag.
[0033] The rearward facing surface(s) in the aft section as shown in Figures provides a surface for the flow to follow, thereby eliminating or significantly reducing this pumping and vortex shedding wave action. Consequently, a more laminar or homogeneous flow around the surface perpendicular to the flow is achieved. As the tail fairing provides a surface for the flow along, the pumping action and resulting wave is eliminated thereby resulting in reduced drag.
[0034] Because the tail fairing's surface(s) provide a surface for the flow to follow, the resulting lamina or homogeneous flow reduces drag. Conceptually, if the drag created by the mirror, mirror housing, forward- or rearward-viewing device is reduced, then it is possible to reduce the overall drag of the vehicle.
[0035] The mirror, mirror housing, rearward- or forward-viewing device's trailing device reduces the overall drag. Clearly, one other convenient method of reducing drag is to add a leading-edge fairing. Other methods, such as vortex generators to energize the boundary layer, introduce intrusiveness that reduces their effectiveness. The benefits of using a single surface include reducing the pumping action and resulting vortex shedding, minimal weight penalty, mechanical simplicity, and low cost. This configuration is depicted in FIG. 6 .
[0036] In one embodiment of the invention, a closed housing reduces drag of the mirror, mirror housing, forward- or rearward-viewing device where the flow that is separated by the leading edge rejoins and thereby reduces the aerodynamic drag of a mirror or rearward-facing device.
[0037] In an alternative embodiment, the single surface provides a buffer for the pumping action of the aforementioned flow to press against and the resulting cushion creates a boundary layer that is effectively mimicking a closed housing by providing a shear layer that runs along a non-existent surface. This cushion provides a surface for the flow to push against reducing the pumping action and resulting drag.
[0038] All embodiments of the invention may be practiced on flight, ground or aquatic vehicles, and at all speeds, including hypersonic.
[0039] While the above embodiments deal with passive structures, it is envisioned that active structures that involve mechanised application of aerodynamic actuators, such as power opening and closing of vents, adjustments of wings and the like, may be deployed either alternatively or in combination with such passive structures.
[0040] Furthermore, while in embodiments the structures described herein may be made with materials such as plexi-glass that are passive and generally rigid, it is envisioned that materials may be available that are softer and more flexible than plexi-glass. Preferably, such a material provides high optical clarity so objects such as the mirror itself can be clearly seen through the material, but also provides flex in response to being pushed or hit so that it does not break in the event that it is jostled or bumped by another object.
[0041] FIG. 7 is a front view of an alternative embodiment showing a side-mounted camera tail application in which a housing houses a rear-viewing camera and a marker light, the rear-viewing camera electronically communicating with a display screen (not shown) for displaying the objects within the field of view of the rear-viewing camera. While the driver within the vehicle may be able to view the camera through the aerodynamic lens cover as the driver is able to view the mirror in other embodiments, in this embodiment even if the camera lens itself is not viewable by the driver the camera's rearward field of view is able to capture at least the objects that a similarly-situated mirror would reflect to a driver's eyes.
[0042] Although embodiments have been described with reference to the drawings, variations may be made without departing from the purpose, spirit and scope as defined in the appended claims. | A method for reducing drag upon land, sea and air based vehicles by applying a tail to the mirror, mirror housing, or rearward-viewing device housing which results in a decrease in drag of the rear-facing mirrors, mirror housings, or rear-ward viewing device, and in total, vehicle drag. In one embodiment, where the material used for the tail passes between an intended observer of the mirror and the mirror itself, or between the rearward-viewing device and objects within its field of view, the material is clear or substantially transparent. | 1 |
BACKGROUND
[0001] 1. Technical Field
[0002] The present invention generally relates to digital frame processing and in particular to panoramic frame processing.
[0003] It finds application in particular, while not exclusively, in picture acquisition devices and in particular, while not exclusively, in single lens devices.
[0004] 2. Related Art
[0005] The approaches described in this section could be pursued, but are not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, the approaches described in this section are not prior art to the claims in this application and are not admitted to be prior art by inclusion in this section.
[0006] Panoramic pictures or mosaics are larger images formed by assembling smaller still or video frames according to a single given direction (e.g. left to right) imposed by the movement of the camera that captured the sequence of frames. The sequence of frames can be acquired by a camera that is rotated (panned for example) around a given axis and in a given sense (for example clockwise or counter clockwise). For the sake of simplification, we consider that the camera is panned in a main direction.
[0007] Typically, a current frame is superimposed on the preceding frame in the sequence. Hence, a mix area of the current image typically corresponds to a common part between the current and one or more of the preceding frames. Also, a copy area of the current frame corresponds to a part of the current frame that is not common with any of the preceding frames and will complete the preceding frame for forming the panoramic picture.
[0008] The definition of the mix and copy areas thus comprises dividing the current frame into two parts (the mix area being the left part and the copy area being the right part, in case of a left to right movement of the camera).
[0009] The superimposition of the current frame on the preceding frame is performed by analysis of all the pixels of each frame, or by analysis of the movement of the camera.
[0010] Once the current frame has been superimposed on the preceding frame, the pixels of the current frame in the mix area are typically mixed or blended with the pixels of the preceding frame that are in the mix area of the current frame, and the copy area is added to the preceding frame to complete the panoramic picture comprising the previous frame.
[0011] Thus, a mosaic or a panoramic picture is obtained from a plurality of frames obtained from different point of views, as the camera acquiring the frames is panned.
[0012] This method can also be used to create stereoscopic panoramic pictures from a single video. This is done by generating at least two panoramic pictures, which can for example correspond to left and right views with a different positioning of the mix and copy areas.
[0013] As the camera is panned, the perspective is different in each frame of the recorded video. When a single panoramic picture is computed, the perspective differences are not a problem as the perspective differences between successive frames can be small enough to be mapped on a planar manifold. However, the different perspectives are problematic when several panoramic pictures are created, for stereoscopic panoramic pictures for example. Indeed, a given copy area for the left view in a first frame corresponds to a copy area for the right view in a second frame, which has a perspective that significantly differs from the perspective of the first frame. In addition to the perspective differences due to the rotation of the camera and which is present even in an ideal case, other perspective differences can be due to the fact that the camera motion is unrestricted in the case of a hand-held camera, and therefore that pitch and roll (rotations around the other axes) of the camera can vary significantly between each frame.
[0014] The result of perspective differences is that a final stereoscopic image, obtained based on the two panoramic pictures, will look distorted, unnatural, and the depth effect may be difficult to perceive, thus creating eye fatigue for a viewer.
[0015] Thus, there is a need to enable computing a non distorted stereoscopic image from at least two panoramic pictures acquired with a single frame acquisition device.
SUMMARY OF THE INVENTION
[0016] To address these needs, a first aspect of the present invention relates to a method of generating at least a first panoramic picture and a second panoramic picture based on a series of frames acquired by one frame acquisition device while the device is panned in a main direction, a global motion value and a perspective transform being computed for each pair of consecutive frames of the series, the global motion value reflecting a displacement in the desired direction between the frames of a pair of frames and the perspective transform reflecting a perspective change between the frames of a pair of frames. For each frame of the series, a first area of the frame is determined for the first panoramic picture and a second area of the frame, distinct from the first area, is determined for the second panoramic picture. The method comprises, upon acquisition of a current frame of the series of frames:
determining a first frame among the already acquired frames of the series of frames, which has a second area that shares at least a common area with the first area of the current frame; calculating a global transform based on the perspective transforms of the pairs of consecutive frames that have been acquired between the first frame and the current frame; determining an adapted first area by applying an inverse of the global transform to the first area of the current frame, the adapted first area being included into the first panoramic picture and the second area of the current frame being included into the second panoramic picture.
[0020] By “main direction”, it is meant a direction of movement in which a user tries to pan his frame acquisition device, such as a camera for example. However, as previously explained, because the camera can be hand-held, some pitch and roll movements can add to the moving of the device in the main direction, which are not in the main direction.
[0021] Therefore, the present invention enables to compensate for the differences of perspective between common scenes of different panoramic pictures. Indeed, upon acquisition of a current frame, the method determines a first frame among the already acquired frames for which the second area has a common area with the first area of the current frame. The difference of perspective is then evaluated between the first frame and the current frame in order to compensate it by applying a global transform. This results in an improvement in obtaining a final stereoscopic image based on the first and second panoramic pictures, which is non distorted, natural and does not cause eye fatigue.
[0022] According to some embodiments, the first and second areas are respectively a first strip and a second strip that are extending in a direction perpendicular to the main direction, centres of the first and second strips being located at constant positions in the frames and being separated by a constant distance from one frame to the other.
[0023] Thus, first and second areas are relevant areas that are representative of the different point of views which are necessary to generate a stereoscopic panorama.
[0024] In complement, the method comprises, before determining the first frame, comparing a sum of the global motion values of the pairs of consecutive frames of the series of frames with the constant distance. The step of determining the first frame is performed if the sum of the global motion values is greater than the constant distance.
[0025] Thus, the comparison step enables to avoid trying to determine a first frame that does not exist yet as the camera has not been panned on a sufficient distance. This enables to enhance the efficiency of the initialization of the method.
[0026] Alternatively or in complement, if the sum of the global motion values is lower than the constant distance, then the first strip of the current frame can be included into the first panoramic picture and the second strip of the current frame can be included into the second panoramic picture, and the method can further comprise acquiring at least one new frame, the new frame being added to the series to form a new series of frames, and calculating a new global motion value between the current frame and the new frame to repeat the step of comparing a sum of the global motion values for each pair of consecutive frames of the new series with the constant distance.
[0027] Such embodiments enable to avoid losing information during initialization of the method. Indeed, at the beginning of the method, it is possible that a first frame can not be determined. Then, the strips can nevertheless be added to the panoramic pictures, without applying a global transform.
[0028] Alternatively or in complement, a width of the first and second strips of a given frame can be proportional to the global motion value of the pair of frames comprised of the given frame and the previous frame acquired before the given frame.
[0029] In some embodiments, the first frame is determined as being the frame of index p for which the absolute value of the following expression is minimized:
[0000] (Σ i∈[p+1;k] GMV i )−d
[0030] where i is an index for each one of the already acquired frames, i varying between p+1 and k, with k being the index of the current frame;
[0031] GMV i is the global motion value of the pair of frames comprised of the frames of indices i−1 and i, respectively;
[0032] d is the constant distance;
[0033] where p is comprised between 0 that is the index of a first acquired frame, and k that is the index of the current frame.
[0034] These embodiments enable to determine the first frame without impacting on available resources, as the determination in only based on comparisons and as the global motion values are progressively determined at each acquisition of a new frame.
[0035] In complement, the index p is stored to be used for a new determination of a new first frame upon reception of a new current frame.
[0036] This enables to accelerate the method when iterated as the index of the first frame can be used for a next acquired frame. Indeed, a new first frame for the new current frame is likely to be near to the previously determined first frame (depending on the variation of the global motion values).
[0037] According to some embodiments, the perspective transforms can be homographies and the global transform can be a composition of the perspective transforms of the pairs of frames that have been acquired between the first frame and the current frame.
[0038] This enables to easily compute the global transform to be used for the determination of the adapted first frame. Thus, the method according to the invention is not time consuming nor resource consuming.
[0039] A second aspect of the invention concerns a computer program product comprising a non-transitory computer readable medium having stored thereon computer program instructions loadable into a computing device and adapted to—when loaded into and executed by the computing device—cause the computing device to perform a method according to anyone of the embodiments of the first aspect of the invention.
[0040] A third aspect of the invention concerns a device for generating at least a first panoramic picture and a second panoramic picture based on a series of frames, the device comprising an acquisition unit adapted to acquire the series of frames while the device is panned in a main direction, a computing unit adapted to compute a global motion value and a perspective transform for each pair of consecutive frames of the series, the global motion value reflecting a displacement in the main direction between the frames of a pair of frames and the perspective transform reflecting a perspective change between the frames of a pair of frames. The device is further arranged to determine, for each frame of the series, a first area of the frame for the first panoramic picture and a second area of the frame, distinct from the first area, for the second panoramic picture. The device further comprises, upon acquisition of a current frame of the series of frames:
a first determination unit for determining a first frame among the already acquired frames of the series of frames, which has a second area that shares at least a common area with the first area of the current frame; a calculation unit for calculating a global transform based on the perspective transforms of the pairs of consecutive frames that have been acquired between the first frame and the current frame; a second determination unit for determining an adapted first area by applying an inverse of the global transform to the first area of the current frame, the adapted first area being included into the first panoramic picture and the second area of the current frame being included into the second panoramic picture.
[0044] According to some embodiments, the first and second areas are respectively a first strip and a second strip that are extending in a direction perpendicular to the main direction, centres of the first and second strips being located at constant positions in the frames and being separated by a constant distance from one frame to the other.
[0045] In complement, the device further comprises a comparison unit for comparing a sum of the global motion values of the pairs of consecutive frames of the series of frames with the constant distance. The first determination unit can then determine the first frame if the sum of the global motion values is greater than the constant distance.
[0046] Alternatively or in complement, the device can further comprise a generation unit for adding, if the sum of the global motion values is lower than the constant distance, the first strip of the current frame to the first panoramic picture and the second strip of the current frame to the second panoramic picture, and the device can be arranged to acquire at least one new frame, the new frame being added to the series to form a new series of frames, and to calculate a new global motion value between the current frame and the new frame to repeat the step of comparing a sum of the global motion values for each pair of consecutive frames of the new series with the constant distance.
[0047] Alternatively or in complement, the device is arranged to determine a width of the first and second strips of a given frame, which is proportional to the global motion value of the pair of frames comprised of the given frame and the previous frame acquired before the given frame.
[0048] According to some embodiments of the invention, the first determination unit determines the first frame as being the frame of index p for which the absolute value of the following expression is minimized:
[0000] (Σ i∈[p+1;k] GMV i )−d
[0049] where i is an index for each one of the already acquired frames, i varying between p+1 and k, with k being the index of the current frame;
[0050] GMVi is the global motion value of the pair of frames comprised of the frames of indices i−1 and i, respectively;
[0051] d is the constant distance;
[0052] where p is comprised between 0 that is the index of a first acquired frame, and k that is the index of the current frame.
[0053] In complement, the device can further comprise a memory to store the index p to be used for a new determination of a new first frame upon reception of a new current frame.
[0054] In some embodiments, the perspective transforms are homographies and the calculation unit calculates the global transform as a composition of the perspective transforms of the pairs of consecutive frames that have been acquired between the first frame and the current frame.
BRIEF DESCRIPTION OF THE DRAWINGS
[0055] Embodiments of the present invention are illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings, in which like reference numerals refer to similar elements and in which:
[0056] FIG. 1 illustrates a panoramic picture comprising a series of frames that have been captured by a single camera;
[0057] FIG. 2 represents a frame, which is divided in a mix area 3 and a copy area;
[0058] FIGS. 3 a , 3 b and 3 c illustrate respectively three frames of a single scene acquired with a same camera from three different points of view, the camera being rotated from the left to the right;
[0059] FIG. 4 illustrates a flowchart representing the steps of a method according to some embodiments of the invention;
[0060] FIGS. 5 a , 5 b and 5 c represent the construction of first and second panoramic pictures at different steps of a method according to some embodiments of the invention;
[0061] FIG. 6 illustrates a device according to some embodiments of the invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0062] Referring to FIG. 1 , there is shown a panoramic picture 1 comprising a series of frames that have been captured by a single camera. The frames may be still images that have been successively captured or frames that originate from a video sequence. In the present example, the panoramic picture 1 has a rectangular shape. However, no restriction is attached to the shape of the panoramic picture, which depends on what a user of the camera wants to create.
[0063] The series of frames comprises frames 2 . 0 , 2 . 1 , 2 . 2 and 2 . 3 . In the example represented on FIG. 1 , the frames have been recorded while the camera is panned from the left to the right. No restriction is attached to the direction and the sense in which the camera is panned (from the right to the left, from top to down, bottom-up, passing several times on the same view, coming back to a same view etc).
[0064] The frames 2 . 0 - 2 . 3 have been successively included into the panoramic picture 1 and superimposed in positions that depend on global motion vectors that can be calculated between pairs of frames. The positions can also be determined based on a comparison of contents of the two frames of a pair of frames. For the sake of simplicity, the global motion vectors of the pairs of frames 2 . 0 - 2 . 1 ; 2 . 1 - 2 . 2 ; 2 . 2 - 2 . 3 , have been represented as perfectly horizontal. However, the movement of the camera can be more complex, either because a user of the camera wishes to record a more complex movement, or because of shivers (causing pitch and roll) in case of a hand-held camera. Thus, the panoramic picture 1 is not limited to a linear panoramic view, but may result from any movement of the camera.
[0065] Thus, by scanning a scene from left to right, one can create the panoramic picture 1 . However, the frames 2 . 0 - 2 . 3 are not only positioned in the panoramic picture 1 , as it will be further explained with reference to FIG. 2 .
[0066] Referring now to FIG. 2 , there is shown a frame 2 , which is divided in a mix area 3 and a copy area 4 . These areas 3 and 4 are defined before inserting the frame 2 in the panoramic picture 1 of FIG. 1 for example, so that the mix area 3 can be blended with a part of the frame that has been acquired before frame 2 , and so that the copy area 4 can be directly copied in the panoramic picture 1 . This principle can be used to create stereoscopic panoramic pictures from a single video, according to some methods of the prior art, by generating two panoramic pictures, for instance corresponding to left and right views, with a different positioning of the mix and copy areas 3 and 4 , as it will be further detailed with reference to FIGS. 3 a to 3 c.
[0067] Referring to FIGS. 3 a to 3 c , there is respectively shown three frames 2 . 31 , 2 . 32 and 2 . 33 of a single scene acquired with a unique camera from three different points of view, the camera being rotated from the left to the right.
[0068] Each of the frames 3 a to 3 b comprises a first position 5 and a second position 6 . The first position 5 , which is located on the left side of the frames, is used to determine strips of the frames to be added to a first panoramic picture, which is dedicated to the right eye. The second position 6 , which is located on the right side of the frames, is used to determine strips of the frames to be added to a second panoramic picture, which is dedicated to the left eye. In this example, the strips would be vertical as the main movement of the camera is horizontal. However, to generate stereo panorama with vertical motion, the camera can be rotated by 90° or 270° and panned horizontally.
[0069] Thus, by generating two panoramic pictures, one from the perspective of a given eye of a virtual user, a three dimensional effect can be created. The first and second positions 5 and 6 can for example represent positions on which a first and a second determined strips are respectively centred, the first strip being dedicated to the first panoramic picture and the second strip being dedicated to the second panoramic picture. For the sake of simplicity, the strips have not been represented on FIGS. 3 a to 3 c , as the widths of the strips can vary. Indeed, the width of the strips of a given frame can for example be proportional to the projection of the global motion vector on a horizontal axis (if the desired movement of the camera is horizontal), hereafter called global motion value. This avoids losing information when the camera is panned too fast.
[0070] FIG. 3 a represents the first frame 2 . 31 that has been acquired by the camera. The recorded frame 2 . 31 comprises an object 7 , which belongs, at least partly, to the second strip centred on the second position 6 .
[0071] FIG. 3 b represents the second frame 2 . 32 that has been acquired by the camera, after the first frame 2 . 31 . As the camera is rotated from the left to the right, the object 7 is now in the middle of the second frame 2 . 32 .
[0072] FIG. 3 c represents the third frame 2 . 33 that has been acquired by the camera, after the second frame 2 . 32 . As the camera is panned from the left to the right, the object 7 is now comprised, at least partly, in the first strip centred on the first position 5 .
[0073] Thus, according to the methods of the prior art, the object 7 will be integrated in the first panoramic picture by pasting the first strip of the third frame 2 . 33 , taken according to a third point of view, whereas the object 7 will be integrated in the second panoramic picture by pasting the second strip of the first frame 2 . 31 , taken according to a first point of view.
[0074] As it can be seen on FIGS. 3 . a and 3 . c, the first and third points of view are significantly different. Thus, the result of such deformations is that a final stereoscopic image, which is obtained based on the first and second panoramic pictures, will look distorted, unnatural and the depth effect may be difficult to perceive. The present invention enables to compensate for the perspective differences, as it will be explained with reference to FIG. 4 .
[0075] Referring to FIG. 4 , there is shown a flowchart representing the steps of a method according to some embodiments of the invention.
[0076] Initially, a constant distance d between the first and second positions 5 and 6 can be prefixed. It is to be noted that when d is fixed to a high value (meaning that the first and second positions are near to the left and right edges of the frames, respectively), the 3D effect is important. The constant distance d between the first and second positions 5 and 6 corresponds to a virtual spacing between a similar system comprising two cameras, each camera generating a panoramic picture. However, the present invention enables to obtain similar results with a single camera.
[0077] At step 41 , a frame I k is acquired by the camera, k being an index. For example, I 0 refers to the first frame that has been acquired by the camera.
[0078] For each incoming frame I k , a global motion vector GMV k can be computed at step 42 . The global motion vector can be representative of the global motion between frame I k−1 and frame I k . In the following, by considering that the movement of the camera is horizontal from the left to the right, we consider the projection of the GMV k on an horizontal axis, the value of the projection being called global motion value and being noted GMV X,k in what follows. For each frame Ik, the global motion value GMV X,k can be stored. It is to be noted that instead of being associated to a given frame, the global motion value of this frame can be associated to the pair of frames comprising the given frame and the frame acquired directly before the given frame.
[0079] At step 42 , a perspective transform H k is computed for the frame I k . The perspective transform can be a homography that can be computed based on a list of pixel correspondences in frames I k−1 and I k (i.e. points that correspond to the same features in both frames). The following set of equations can then be solved:
[0000]
F
k
=H
k
.F
k−1
[0080] where H k is a 3*3 matrix,
[0081] F k is a vector representing frame I k , and F k−1 is a vector representing frame I k−1 .
[0082] For example, F k−1 can be the vector (x, y, 1), where x and y are the coordinates of a given pixel in the frame I k−1 , and F k is the vector (x′, y′, z′), where x′/z′ and y′/z′ are the coordinates of the pixel of frame I k that corresponds to the given pixel in the frame I k−1 .
[0083] Based on these coordinates, the non linear set of equations can be solved by conventional computer vision methods for example.
[0084] These pixel correspondences can be computed in several ways. For example, the global motion vector may have been determined by a classical block matching algorithm, whose local motion vectors can be re-used.
[0085] For each frame I k , the perspective transform H k can then be stored.
[0086] At step 44 , it is then determined whether the sum of the global motion values of all the frames that have been acquired (meaning the frames that are comprised between the frame I 0 and the frame I k ) is greater than or equal to the constant distance d.
[0087] If this is not the case, a first strip centred on the first position of frame I k and a second strip centred on the second position of frame I k are taken from the frame I k to be pasted respectively in the first and second panoramic pictures, at step 45 . The method is then iterated by coming back to step 41 .
[0088] Else, at step 46 , it is determined which frame I p , p being comprised between 0 and k, has a second strip at the same position (meaning at the same physical position in the recorded scene) as the first strip of the current frame I k . Of course, if the camera is panned from the right to the left, it is determined which frame I p , p being comprised between 0 and k, has a first strip at the same position as the second strip of the current frame I k . This will be better comprised by referring to FIGS. 5 a , 5 b and 5 c.
[0089] In order to identify the movement of the camera, and thus of the acquired frame, a horizontal axis 50 is represented on FIGS. 5 a , 5 b and 5 c.
[0090] Referring to FIGS. 5 a , there is shown the construction of first and second panoramic pictures at the beginning of a method according to some embodiments of the invention, when the first frame I 0 , referenced 2 . 50 , has been acquired by the camera. A first strip 51 . 0 is determined around the first position 5 and a second strip 52 . 0 is determined around the second position 6 . As no global motion vector has been computed for the first frame I 0 2 . 50 , the width of the first and second strips 51 . 0 - 52 . 0 can be fixed to a default value.
[0091] Referring now to FIG. 5 b , there is shown the construction of first and second panoramic pictures after the acquisition of p+1 frames by the camera, according to some embodiments of the invention. Only frames I 0 and I p have been represented for the sake of clarity. Frame I p is referenced 2 . 5 p. As the camera is panned from the left to the right, frame I p is shifted to the right compared to frame I 0 . A first strip 51 . p of frame I p is added to the first panoramic picture, which is referenced first panoramic picture 53 . The first strip 51 . p of frame I p is centred on the first position 5 . A second strip 52 . p of frame I p is added to the second panoramic picture, which is referenced second panoramic picture 54 . The second strip 52 . p of frame I p is centred on the second position 6 of frame I p . As already explained, the width of the first and second strips 51 . p - 52 . p can be proportional to the global motion value GMV X,p of frame I p . The abscissa (obtained by projection on the axis 50 ) of the first position 5 of frame I p is noted x p — r . The abscissa of the second position 6 of frame I p is noted x p — l .
[0092] Referring now to FIG. 5 c , there is shown the construction of first and second panoramic pictures 53 - 54 , after the acquisition of k+1 frames by the camera, according to some embodiments of the invention. Only frames I 0 , I p and I k have been represented for the sake of clarity. Frame I k is referenced 2 . 5 k. As the camera is panned from the left to the right, frame I k is shifted to the right compared to frame I p . A first strip 51 . k of frame I k is added to the first panoramic picture 53 . The first strip 51 . k of frame I k is centred on the first position 5 . A second strip 52 . k of frame I k is added to the second panoramic picture 54 . The second strip 52 . k of frame I k is centred on the second position 6 of frame I k . As already explained, the width of the first and second strips 51 . k - 52 . k can be proportional to the global motion value GMV X,k of frame I k . The abscissa (obtained by projection on the axis 50 ) of the first position 5 of frame I k is noted x k — r . The abscissa of the second position 6 of frame I k is noted x k — l . As already explained, the constant distance d, referenced 55 , between the first and second positions 5 and 6 of a given frame, is held constant.
[0093] On FIG. 5 c , it can be seen that x k — r and x p — l are very near, that is to say that the second strip 52 . p of the frame I p covers approximately the same scene content as the first strip 51 . k of frame I k .
[0094] Referring back to FIG. 4 , index p can be determined at step 46 such that p is the index for which the absolute value of the difference between x k — r and x p — l is minimal. It is to be noted that it is not always possible to find p such that x p — l is equal to x k — r , in spite of d being constant, because the motion of the camera is discrete and under the control of the user of the camera.
[0095] The difference between x k — r and x p — l can be rewritten based on the global motion values GMV X,i of the frames:
[0000] x k — r −x p — l =(Σ i∈[p+1;k] GMV X,i )− d
[0096] The minimization of the absolute value of x k — r −x p — l can thus be performed very simply by scanning the previously acquired frames and by cumulating and storing the global motion values sequentially backward, starting from the current picture I k , then k−1, until reaching a value p 1 for which the sum of the global motion values becomes greater than d. Then, p is made equal to p 1 or to p 1 +1, depending on which one of the two gives the smallest absolute value for the difference x k — r −x p — l .
[0097] No restriction is attached to the way frame I p is determined. Indeed, other strategies can be thought for frame I p identification (for example storing the result p for frame I k in order to accelerate the search for a new frame I k+1 ), which do not preclude the principle of the present invention.
[0098] At step 47 , a global transform H p→k between the frame I p and the frame I k is determined based on the perspective transforms H i (which are homographies in this particular example) of the frames comprised between the frames I p and I k . This can be done without storing the intermediate frames, by multiplying the homographies according to the following formula:
[0000] H p→k =H k *H k−1 * . . . *H p+1 ;
[0099] Thus, it is ensured hat the memory requirements of the method according to the present invention are not significantly higher than conventional methods, because every homography is a 3*3 matrix.
[0100] The global transform H p→k is the perspective transform that puts the frame I p in the same virtual point of view as the current frame I k . To generate the first panoramic picture 53 according to the invention, the first strip 51 . k of the current frame I k should be put in the same point of view as the second strip 52 . p of the frame I p .
[0101] To this purpose, at step 48 , the inverse of the global transform H p→k is calculated and applied to the first strip 51 . k of the current frame I k to obtain an adapted first strip.
[0102] At step 49 , the second strip 52 . k and the adapted first strip of the current frame I k are respectively added to the second panoramic picture 54 and to the first panoramic picture 53 . The method can then be iterated by coming back to step 41 upon acquisition of a new frame I k+1 .
[0103] Referring to FIG. 6 , there is a shown a device 60 according to some embodiments of the invention.
[0104] The device 60 comprises an acquisition unit 61 that is adapted to acquire frames. The device 60 further comprises a first calculation unit 62 that is adapted to perform the steps 42 and 43 that are illustrated on FIG. 4 , in order to determine the global motion value GMV X,k and the perspective transform H k of the current frame I k . The global motion value GMV X,k and the perspective transform H k can then be stored in a memory 63 . The device 60 further comprises a comparison unit 64 that is adapted to perform the step 44 illustrated on FIG. 4 , in order to determine whether the sum of the global motion values of all the frames that have been acquired is less than the constant distance d.
[0105] The device 60 comprises a first determination unit 65 that is adapted to perform the step 46 illustrated on FIG. 4 , in order to determine which frame I p , p being comprised between 0 and k, has a second strip 52 . p at the same position as the first strip 51 . k of the current frame I k .
[0106] The device 60 further comprises a second calculation unit 66 to perform the step 47 illustrated on FIG. 4 , in order to determine the global transform H p→k , and a second determination unit 67 adapted to perform the step 48 illustrated on FIG. 4 , in order to determine an adapted first strip. The device also comprises a generating unit 68 to generate the first panoramic picture by adding the second strip 52 . k and the adapted first strip of the current frame I k and also to perform step 45 illustrated on the FIG. 4 .
[0107] Thus, the present invention enables to compensate for the perspective differences between corresponding strips dedicated to the first and second panoramic pictures. In this way, first and second panoramic pictures are generated with virtual cameras having the same orientation, without impacting the memory requirements of the algorithm and its complexity.
[0108] Embodiments of 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 an information processing system—is able to carry out these methods. 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 conversion to another language. Such a computer program can be stored on a computer or machine readable medium allowing data, instructions, messages or message packets, and other machine readable information to be read from the medium. The computer or machine readable medium may include non-volatile memory, such as ROM, Flash memory, Disk drive memory, CD-ROM, and other permanent storage. Additionally, a computer or machine readable medium may include, for example, volatile storage such as RAM, buffers, cache memory, and network circuits. Furthermore, the computer or machine readable medium may comprise computer or machine readable information in a transitory state medium such as a network link and/or a network interface, including a wired network or a wireless network, that allow a device to read such computer or machine readable information.
[0109] Embodiments of the invention have been described above in detail with reference to embodiments thereof. However, as is readily understood by those skilled in the art, other embodiments are equally possible within the scope of the present invention, as defined by the appended claims.
[0110] Expressions such as “comprise”, “include”, “incorporate”, “contain”, “is” and “have” are to be construed in a non-exclusive manner when interpreting the description and its associated claims, namely construed to allow for other items or components which are not explicitly defined also to be present. Reference to the singular is also to be construed in be a reference to the plural and vice versa.
[0111] While there has been illustrated and described what are presently considered to be the preferred embodiments of the present invention, it will be understood by those skilled in the art that various other modifications may be made, and equivalents may be substituted, without departing from the true scope of the present invention. Additionally, many modifications may be made to adapt a particular situation to the teachings of the present invention without departing from the central inventive concept described herein. Furthermore, some embodiments of the present invention may not include all of the features described above. Therefore, it is intended that the present invention not be limited to the particular embodiments disclosed, but that the invention include all embodiments falling within the scope of the invention as broadly defined above.
[0112] A person skilled in the art will readily appreciate that various parameters disclosed in the description may be modified and that various embodiments disclosed and/or claimed may be combined without departing from the scope of the invention. | The invention concerns a method of generating at least a first panoramic picture and a second panoramic picture based on a series of frames acquired by one frame acquisition device while said device is panned in a main direction, a global motion value and a perspective transform being computed for each pair of consecutive frames of the series, the global motion value reflecting a displacement in the main direction between the frames of a pair of frames and the perspective transform reflecting a perspective change between the frames of a pair of frames. For each frame of the series, a first area of the frame is determined for the first panoramic picture and a second area of the frame, distinct from the first area, is determined for the second panoramic picture. The method comprises, upon acquisition of a current frame of the series of frames, determining a first frame among the already acquired frames of the series of frames, which has second area that shares at least a common area with the first area of the current frame, calculating a global transform based on the perspective transforms of the pairs of consecutive frames that have been acquired between the first frame and the current frame and determining an adapted first area by applying an inverse of the global transform to the first area of the current frame, the adapted first area being included into the first panoramic picture and the second area of the current frame being included into the second panoramic picture. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
The present application is a continuation in part of application Ser. No. 436,646, filed Oct. 25, 1982, now abandoned, the disclosure of which is hereby incorporated by reference hereto.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method of manufacturing an aqueous dispersion of fortified rosin for use in paper sizing, and more particularly to a method of manufacturing the same by the phase inversion process from W/O or water-in-oil type dispersion to O/W or oil-in-water type in the presence of an effective dispersing agent thus far not used in paper sizing.
2. Description of Material Information
Aqueous dispersions of rosin and its derivatives have been widely used in paper sizing and are commonly known as rosin sizes. The sizing process involves the separate addition of a dilute aqueous dispersion of rosin size and alum to a pulp slurry. Fortified rosins are made by adducting an α,β unsaturated carboxylic acid to ordinary rosin, and essentially, mixtures comprised of unreacted rosin and adducted rosin, and are much more effective for sizing. Typical acids used are fumaric acid, acrylic acid, maleic acid, itaconic acid, citraconic acid, and the anhydrides of the latter three, although fumaric acid and maleic anhydride are by far the more common acids used. In general, if rosin is treated with formaldehyde, or with modified formaldehyde, the resultant addition product increases the efficiency of rosin sizes.
U.S. Pat. No. 3,565,755 discloses a solvent emulsifying method giving an emulsion. The process includes solving the fortified rosin in a water-insoluble, volatile organic solvent, such as benzene or toluene, mixing the solution with an aqueous solution of alkaline material, or a water-soluble salt of rosin and/or fortified rosin, homogenizing the unstable mixture to produce a stable emulsion, and removing the organic solvent by distillation. A disadvantage of this process is that the intermediate fortified rosin solution in the organic solvent is thermally unstable and tends to aggregate at higher temperatures.
Australian Patent Application No. 69365, filed on May 24, 1974, discloses a method of manufacturing aqueous rosin dispersion by homogenizing a molten rosinous substance at a temperature of about 150° to about 195° C. under a pressure of about 140 kg/cm 2 to about 560 kg/cm 2 , in the presence of an anionic dispersing agent, including saponified rosin base material, sodium alkylbenzene sulfonate, sodium naphthalene sulfonic acid, sodium lauryl sulfate, and the ammonium salt of the sulfate ester of an alkylphenoxy (polyethyleneoxy)ethanol.
U.S. Pat. No. 4,148,665 Kulick et al. discloses that colloidal aqueous dispersions of rosin possess improved mechanical and heat stability when they contain small amount of a dissolved water-dispersible emulsifying agent selected from the group consisting of tetrasodium N-(1,2-dicarboxyethyl)-N-octadecylsulfosuccinate, disodium N-octadecylsulfosuccinate, disodium dodecylpenta(ethoxy)ethylsulfosuccinate, and disodium decylsulfosuccinate as stabilizing agent. Such dispersions are prepared by the use of organic solvent such, as toluene, and by passing the material in solution through a homogenizer and removing the solvent. In this invention the phase inversion process was not used. The formula of this invention called for 5 ethoxy groups to be present.
U.S. Pat. No. 4,203,776, to Greiner discloses a process for preparing paper size from fortified rosin by the use of the phase inversion process, using as dispersing agents salts of sulfosuccinic acid-ethylene oxide condensates having the following general formula, in which R is a normal or branched chain alkyl group containing from 4 through 18 carbon atoms, and n is an integer of 4 through 25: ##STR2## As can be seen from the formula, the presence of a benzene ring is required for these dispersing agents.
Finally, U.S. Pat. No. 4,309,338, to Okumichi et al. discloses a process for preparing an aqueous dispersion of a rosin-base material by the phase inversion process, employing at least one of the following dispersants: ##STR3## wherein R 1 is a hydrocarbon residue having 4 to 18 carbon atoms, m is an integer of 1 or 2, n is an integer of 4 to 25, X is a hydrogen atom or a hydroxyl group, and M is a monovalent cation, and ##STR4## wherein R 2 is a hydrogen atom or a lower alkyl group, A is a straight- or branched-chain alkylene having 2 to 3 carbon atoms, p is an integer of 4 to 25, and Q is a monovalent cation. Again, the presence of a benzene ring in the dispersants is required. The inventors pointed out that the excellent sizing effects, high mechanical and dilution stabilities, and improved foaming properties are achievable only when at least one dispersing agent fitting at least one of the above two formulae is used.
SUMMARY OF THE INVENTION
The object of the present invention is to provide a method of manufacturing a stabilized fortified rosin dispersion with excellent sizing efficiency via the phase inversion dispersion process, using a new type of dispersing agent which does not contain a benzene ring.
According to the present invention, the performance of dispersions manufactured by the phase inversion processes thus far proposed, can be improved by the use of a new type dispersing agent having the formula: ##STR5## wherein R is a straight- or branched-chain alkyl group having 4 to 24 carbon atoms, n is an integer of 6 to 20 inclusive, and M + is a cation selected from the group consisting of Na + , K + , and NH 4 + . Compounds having the formula (I) have not previously been used as dispersing agents, nor has their suitability for such use been appreciated.
The advantage of the present invention is that an aqueous dispersion containing a small amount of the dispersing agent is quite stable for storage and mechanical shear action experienced in transfer pumps and lines. Moreover, such dispersions have excellent suitability for use in paper sizing.
DETAILED DESCRIPTION OF THE INVENTION
The rosin used to prepare the fortified rosin can be any of the commercially available types of rosin, such as wood rosin, gum rosin, tall oil rosin, and mixtures thereof in their crude or refined state.
The method of manufacturing the aqueous fortified rosin dispersion of the present invention is, in general, as follows:
Fortified rosin as described above under "Description of the Prior Art" is allowed to melt in advance. To this is added with good agitation, an aqueous solution of the dispersing agent having the formula (I): ##STR6##
A dispersion of W/O type is made by this operation. Subsequent slow sequential addition of warm water under agitation at a temperature of 70° to 100° C. causes phase inversion from W/O type to O/W type, to yield an aqueous dispersion of the fortified rosin of the present invention.
A dispersing agent having the general formula (I) can be made by the reaction of higher alcohols with ethylene oxide in the presence of water, followed by monoesterification with sulfosuccinic acid and neturalization with aqueous alkali.
The number of ethylene oxide groups n in the formula (I) is an integer of 6 to 20, in which 8 to 16 is more preferable, and 9 to 12 is most preferable. If n exceeds 20, the dispersing agent is less effective.
As shown below in example 7, when n=5 in formula (I) of the present invention, the dispersing agent is less effective, even though the phase inversion process is substituted for the water-insoluble solvent method.
One outstanding characteristic of general formula (I) of the present invention is that it contains no benzene ring. This may be the reason for the effectiveness of the dispersing agents of the present invention, although this point is not known for certain at this time.
The amount of the dispersing agent to be used according to the present invention is in general about 2 to 4% by wt. to molten rosin. Increased use is not economical.
Particular hydrocarbons and the like, including paraffin wax, microcrystalline wax, oxidized wax, petroleum resin and turpentine resin, can be added as fillers or extenders to the fortified rosin, in amounts ranging up to about 30%, without much loss of performance.
The following examples 1 through 6 and examples for comparison 7 through 16 serve to illustrate preferred methods of manufacturing the aqueous fortified rosin dispersion of the invention, and to demonstrate the superior results obtainable through the use of sizing containing the dispersing agent of the invention. However, the Examples are not intended to restrict the spirit and the scope of the present invention.
EXAMPLE 1
Eight parts (weight basis, the same hereinafter) of fumaric acid were dissolved in 92 parts of molten formaldehyde-modified tall oil rosin, and maintained at 200° C. for 3 hours for adduct formation. (The product, regardless of the composition, is hereinafter referred to as fortified rosin.)
The fortified rosin was allowed to melt completely at 180° C., then cooled to 130° C., and mixed slowly over 5 mintues with 22 parts of 13.7% aqueous solution of the dispersing agent (i.e., 3 parts of the dispersing agent in water), wherein the dispersing agent has the formula (I), where R is a mixture of α methyl alkyl groups, and n is 7. Before mixing the solution of dispersing agent is heated to about 90° C. The temperature at the end of mixing is 95° C. Slow sequential addition of about 44 parts of warm water at 95° C., results in a white, creamy, finely dispersed emulsion of W/O type containing about 60% solids, which is readily convertible to O/W type, by mixing it quickly with 128 parts of warm water with violent agitation for one minute. The O/W emulsion is then quenched to 30° C. The aqueous dispersion obtained has a solids content of 35% and is colored pale blue, and has excellent stability for storage.
EXAMPLES 2 THROUGH 4
The procedure of Example 1 was subtantially repeated except that the numeral n in the formula (I) of the dispersing agent is:
in Example 2, 9.5 on average.
in Example 3, 12 on average.
in Example 4, 16 on average.
EXAMPLE 5
The procedure of Example 1 was substantially repeated, except 90 parts of the fortified rosin and 10 parts of paraffin were used instead of 100 parts of the fortified rosin, and the numberal n in the formula (I) was 9.5. The aqueous dispersion obtained contained 35% solids and was colored pale blue.
EXAMPLE 6
The procedure of Example 1 was substantially repeated, except the fortified rosin was prepared as follows:
Six parts of fumaric acid were dissolved in 94 parts of molten formaldehyde-modified tall oil rosin, and maintained at 200° C. for 3 hours for adduct formation.
The following examples are shown for comparison, in order to show the superiority of the dispersing agents of the present invention.
EXAMPLE 7
The procedure of Example 1 was substantially repeated, except the numeral n in the formula (I) is 5, or less than the minimum value of 6. This dispersing agent thus has the same number of ethoxy groups as emulsifier C, used in U.S. Pat. No. 4,148,665, discussed above.
EXAMPLES 8 THROUGH 14
The procedure of Example 1 was substantially repeated, except for not using the dispersing agent of the formula (I), and instead, using:
in Example 8, 3 parts of ##STR7## the resulting aqueous dispersion obtained containing 33% solids and being white in color,
in Example 9, 3 parts of ##STR8## the resulting aqueous dispersion obtained containing 32% solids and being white in color;
in Example 10, 4.5 parts of ##STR9## the resulting aqueous dispersion obtained containing 35% solids and being pale blue in color;
in Example 11, 3 parts of ##STR10## (which would conform to the general formula listed in U.S. Pat. No. 4,203,776, discussed above) the resulting aqueous dispersion obtained containing 35% solids and being white in color;
in Example 12, 5 parts of ##STR11## (which is again the same compound as listed in Example 11) the resulting aqueous dispersion obtained having a solids content of 35% and a pale blue color;
in Example 13, 3 parts of ##STR12## (which is a member of the class of compounds proposed in U.S. Pat. No. 4,309,338) the aqueous dispersion obtained having a solids content of 35% and a white color;
in Example 14, ##STR13## (which is again a member of the class of compounds proposed in U.S. Pat. No. 4,309,338 (Example 20)) the aqueous dispersion obtained having a solids content of 35% and a white appearance.
EXAMPLES 15 AND 16
The procedure of Example 1 was substantially repeated, except that the fortified rosin of Example 7 was prepared by dissolving 6 parts of fumaric acid in 94 parts of molten formaldehyde-modified tall oil rosin, and using, instead of the dispersing agent of the formula (I):
in Example 15, 3 parts of ##STR14## the aqueous dispersion obtained containing 35% solids and being pale blue in color;
in Example 16, 3 parts of ##STR15## the aqueous dispersion obtained containing 35% solids and having a pale blue appearance.
The aqueous dispersions obtained in Examples 1 through 6, and Examples for comparison 7 through 16 have the properties shown in Table 1.
As can be seen from Table I, the aqueous fortified rosin dispersions of the present invention (Examples 1 through 6) are much smaller in mean particle size and more stable against hard water and in storage than a preparation in accordance with the general formula of U.S. Pat. No. 4,203,776 (Examples 11 and 12) and the preparations in accordance with the general formula of U.S. Pat. No. 4,309,338 (Examples 13 through 16).
The aqueous fortified rosin dispersions of Examples 1 through 16 were further examined by the Stoeckigt sizing test (Japanese Industrial Standard JIS P 8122).
The slurry sample is prepared as follows: To the beaten pulp (L/N BKP, L/N=1/1, Freeness 430 ml, c.s.f.) is added 0.3% or 0.5% of the aqueous dispersion depending upon the experiment, and 1.5% of alum so as to prepare a uniform stock. The percentages are based on the weight of the dry pulp. The stock is made into a sheet of 65 g/m 2 at a temperature of 30° C. In other respects, the ordinary method is followed.
The results of measurements on each sample paper prepared are as shown in Table 2.
TABLE 1______________________________________Properties of aqueous fortified rosin dispersions Mean diameter Stability Stability for Amount based on against storageEx- used number of hard (25° C.)ampleNumeral (%) particles water (3)No. n or m (1) (10.sup.-3 mm) (2) (%)______________________________________1 7 3.0 0.7 None 0.22 9.5 3.0 0.4 None L.T. (4) 0.13 12 3.0 0.3 None L.T.0.14 16 3.0 0.3 None L.T.0.15 9.5 3.0 0.2 None L.T.0.16 9.5 3.0 0.2 None L.T.0.17 5 3.0 1.5 Small 1.0 amount8 9.5 3.0 1.0 Small 0.6 amount9 9.5 3.0 1.0 None 0.510 9.5 4.5 0.3 None 0.211 9.5 3.0 1.0 Small 0.6 amount12 9.5 5.0 0.3 None 0.213 12 3.0 1.4 Small 6.7 amount14 12 3.0 1.7 Small 9.8 amount15 12 3.0 0.6 None 0.416 12 3.0 0.9 None 0.6______________________________________ Remarks: (1) Based on the fortified rosin. (2) Based on the observation of aggregate flocs in the dispersion after 4 hrs. maintained at 25° C., which has a fortified rosin content of 5%, and is made by dilution of said fortified rosin dispersion with hard water of 11.2 DH. (3) Based on resin precipitate after 2 months. (4) L.T. stands for "less than".
TABLE 2______________________________________Results of the sizing tests Added amount of the aqueous Fortified rosin dispersion based upon theExample fumaric acid wt. of the dry pulp (%)No. content (%) 0.3 0.5______________________________________1 8.0 15.0 24.12 8.0 15.6 24.53 8.0 15.2 24.14 8.0 13.9 23.15 8.0 13.5 23.36 6.0 10.9 21.27 8.0 10.6 20.88 8.0 10.2 20.39 8.0 10.6 20.710 8.0 9.0 18.711 8.0 11.7 20.812 8.0 8.6 19.013 8.0 10.3 20.114 8.0 10.1 19.415 6.0 7.4 18.616 6.0 7.2 18.0______________________________________ | A method of manufacturing an aqueous O/W dispersion of fortified rosin for use in the sizing of paper by mixing the same with water and a dispersing agent by first forming a dispersion of the W/O type in the presence of the dispersing agent and then turning the first dispersion to an O/W type by sequential addition of water thereto, wherein said dispersing agent has the general formula: ##STR1## in which R is a straight- or branched-chain alkyl group having 4 to 24 C atoms, n is an integer of 6 to 20, and M + is a cation selected from the group consisting of Na + , K + , and NH 4 + . | 8 |
CROSS REFERENCE TO RELATED APPLICATION
[0001] Pursuant to 35 U.S.C. §119(e), this application claims priority to U.S. Provisional Application Ser. No. 61/026,212, filed Feb. 5, 2008, the contents of which are hereby incorporated by reference.
TECHNICAL FIELD
[0002] This disclosure relates to methods of forming a photoactive layer, as well as related compositions, photovoltaic cells, and photovoltaic modules.
BACKGROUND
[0003] Photovoltaic cells are commonly used to transfer energy in the form of light into energy in the form of electricity. A typical photovoltaic cell includes a photoactive material disposed between two electrodes. Generally, light passes through one or both of the electrodes to interact with the photoactive material. As a result, the ability of one or both of the electrodes to transmit light (e.g., light at one or more wavelengths absorbed by a photoactive material) can limit the overall efficiency of a photovoltaic cell. In many photovoltaic cells, a film of semiconductive material (e.g., indium tin oxide) is used to form the electrode(s) through which light passes because, although the semiconductive material can have a lower electrical conductivity than electrically conductive materials, the semiconductive material can transmit more light than many electrically conductive materials.
SUMMARY
[0004] This disclosure relates to methods of forming a photoactive layer, as well as related compositions, photovoltaic cells, and photovoltaic modules.
[0005] In one aspect, this disclosure features methods that include (1) applying a composition containing first and second materials on a substrate to form an intermediate layer supported by the substrate, (2) removing at least some of the second material from the intermediate layer to form a porous layer having pores; and (3) disposing a third material in at least some of the pores of the porous layer to form a photoactive layer. The first material is different from the second material.
[0006] In another aspect, this disclosure features articles that include first and second electrodes, and a photoactive layer between the first and second electrodes. The photoactive layer includes a first semiconductor material and a second semiconductor material different from the first semiconductor material. The first and second semiconductor materials do not both have a solubility of at least about 0.1 mg/ml in any solvent at about 25° C. The article is configured as a photovoltaic cell.
[0007] In another aspect, this disclosure features articles that include first and second electrodes, and a photoactive layer between the first and second electrodes. The photoactive layer includes first and second semiconductor materials. The second semiconductor material has a solubility of at most about 10 mg/ml in any solvent at about 25° C. The article is configured as a photovoltaic cell.
[0008] In another aspect, this disclosure features articles that include first and second electrodes, and a photoactive layer between the first and second electrodes. The photoactive layer includes first and second semiconductor materials selected from the group consisting of a water-soluble semiconductor polymer and an organic solvent-soluble fullerene, an organic solvent-soluble semiconductor polymer and a water-soluble fullerene, an organic solvent-soluble semiconductor polymer and a water-soluble semiconductor polymer, and an organic solvent-soluble semiconductor polymer and a fullerene or a carbon allotrope that is not soluble in any solvent; and the article is configured as a photovoltaic cell.
[0009] In still another aspect, this disclosure features methods that include (1) providing an intermediate layer including a first material and a second material different from the first material, (2) removing at least some of the second material from the intermediate layer to form a porous layer having pores, and (3) disposing a third material in at least some of the pores of the porous layer to form a photoactive layer.
[0010] Embodiments can include one or more of the following features.
[0011] In some embodiments, the first, second, or third material is a semiconductor material.
[0012] In some embodiments, the first material includes an electron donor material. In certain embodiments, the electron donor material is selected from the group consisting of polythiophenes, polyanilines, polycarbazoles, polyvinylcarbazoles, polyphenylenes, polyphenylvinylenes, polysilanes, polythienylenevinylenes, polyisothianaphthanenes, polycyclopentadithiophenes, polysilacyclopentadithiophenes, polycyclopentadithiazoles, polythiazolothiazoles, polythiazoles, polybenzothiadiazoles, poly(thiophene oxide)s, poly(cyclopentadithiophene oxide)s, polythiadiazoloquinoxaline, polybenzoisothiazole, polybenzothiazole, polythienothiophene, poly(thienothiophene oxide), polydithienothiophene, poly(dithienothiophene oxide)s, polyfluorenes, polytetrahydroisoindoles, and copolymers thereof. For example, the electron donor material can include polythiophenes (e.g., poly(3-hexylthiophene) (P3HT)), polycyclopentadithiophenes (e.g., poly(cyclopentadithiophene-co-benzothiadiazole)), or copolymers thereof.
[0013] In some embodiments, the second or third material includes an electron acceptor material. In certain embodiments, the electron acceptor material includes a material selected from the group consisting of fullerenes, inorganic nanoparticles, oxadiazoles, discotic liquid crystals, carbon nanorods, inorganic nanorods, polymers containing CN groups, polymers containing CF 3 groups, and combinations thereof.
[0014] In some embodiments, the pores have an average diameter of at least about 20 nm (e.g., at least about 100 nm).
[0015] In some embodiments, the second or third material includes an electron donor material. In such embodiments, the first material can include an electron acceptor material.
[0016] In some embodiments, the third material is different from the first and second materials.
[0017] In some embodiments, the composition further includes a processing additive. In certain embodiments, the processing additive is selected from the group consisting of an alkane substituted with halo, thiol, CN, or COOR, R being H or C 1 -C 10 alkyl; a cyclopentadithiophene optionally substituted with C 1 -C 10 alkyl; a fluorene optionally substituted with C 1 -C 10 alkyl; a thiophene optionally substituted with C 1 -C 10 alkyl; a benzothiadiazole optionally substituted with C 1 -C 10 alkyl; a naphthalene optionally substituted with C 1 -C 10 alkyl; and a 1,2,3,4-tetrahydronaphthalene optionally substituted with C 1 -C 10 alkyl.
[0018] In some embodiments, the processing additive is an alkane substituted with Cl, Br, I, SH, CN, or COOCH 3 . For example, the alkane can be a C 6 -C 12 alkane (e.g., octane). In certain embodiments, the processing additive is 1,8-diiodooctane, 1,8-dibromooctane, 1,8-dithioloctane, 1,8-dicyanooctane, or 1,8-di(methoxycarbonyl)octane.
[0019] In some embodiments, the at least some of the second material is removed by contacting the intermediate layer with a solvent. In certain embodiments, the solvent includes a compound selected from the group consisting of an alkane substituted with halo, thiol, CN, or COOR, R being H or C 1 -C 10 alkyl; a cyclopentadithiophene optionally substituted with C 1 -C 10 alkyl; a fluorene optionally substituted with C 1 -C 10 alkyl; a thiophene optionally substituted with C 1 -C 10 alkyl; a benzothiadiazole optionally substituted with C 1 -C 10 alkyl; a naphthalene optionally substituted with C 1 -C 10 alkyl; and a 1,2,3,4-tetrahydronaphthalene optionally substituted with C 1 -C 10 alkyl.
[0020] In some embodiments, the solvent includes an alkane substituted with Cl, Br, I, SH, CN, or COOCH 3 . For example, the alkane can be a C 6 -C 12 alkane (e.g., octane). In certain embodiments, the solvent is 1,8-diiodooctane, 1,8-dibromooctane, 1,8-dithioloctane, 1,8-dicyanooctane, or 1,8-di(methoxycarbonyl)-octane.
[0021] In some embodiments, the at least some of the second material is removed by applying a vacuum to the intermediate layer, heating the intermediate layer, or a combination thereof.
[0022] In some embodiments, the substrate includes a first electrode. In such embodiments, the methods can further include disposing a second electrode on the photoactive layer to form a photovoltaic cell.
[0023] In some embodiments, the first material and the third material (or the second semiconductor material in a photoactive layer) do not both have a solubility of at least about 0.1 mg/ml (e.g., at least about 1 mg/ml or at least about 10 mg/ml) in any solvent at about 25° C.
[0024] In some embodiments, the third material (or the second semiconductor material in a photoactive layer) has a solubility of at most about 10 mg/ml (e.g., at most about 1 mg/ml or at most about 0.1 mg/ml) in any solvent at about 25° C.
[0025] In some embodiments, the second semiconductor material in a photoactive layer includes a carbon nanotube or a carbon nanorod.
[0026] In some embodiments, the first semiconductor material in a photoactive layer includes a cross-linked material.
[0027] Embodiments can include one or more of the following advantages.
[0028] Without wishing to be bound by theory, it is believed that the intermediate layer described above can serve as a template to form a photoactive layer with a desired morphology by replacing one of the first and second semiconductor materials with a third semiconductor material.
[0029] Without wishing to be bound by theory, it is believed that one advantage of forming a photoactive layer through an intermediate layer with a desired morphology is that the morphology of the intermediate layer does not change substantially during any subsequent processes.
[0030] Without wishing to be bound by theory, it is believed that one advantage of the methods described above is that they allow the preparation of a heterojunction photoactive layer with a desired morphology even though the two semiconductor materials (e.g., two semiconductor materials that do not have sufficient solubility in a common solvent) contained in the photoactive layer would otherwise result in an unfavorable morphology.
[0031] Other features and advantages will be apparent from the description, drawings, and claims.
DESCRIPTION OF DRAWINGS
[0032] FIG. 1 is a cross-sectional view of an embodiment of a photovoltaic cell.
[0033] FIG. 2 is a schematic of a system containing multiple photovoltaic cells electrically connected in series.
[0034] FIG. 3 is a schematic of a system containing multiple photovoltaic cells electrically connected in parallel.
[0035] Like reference symbols in the various drawings indicate like elements.
DETAILED DESCRIPTION
[0036] FIG. 1 shows a cross-sectional view of a photovoltaic cell 100 that includes a substrate 110 , an electrode 120 , a hole carrier layer 130 , a photoactive layer 140 , a hole blocking layer 150 , an electrode 160 , and a substrate 170 . Electrodes 120 and 160 are electrically connected to an external load.
[0037] In some embodiments, photoactive layer 140 can be prepared by (1) applying a composition containing first and second materials on a substrate to form an intermediate layer supported by the substrate; (2) removing at least some of the second material from the intermediate layer to form a porous layer having pores; and (3) disposing a third material in at least some of the pores of the porous layer to form a photoactive layer. The first material is different from the second material. In certain embodiments, the third is different from the first and second materials. In some embodiments, the first, second, or third material is a semiconductor material.
[0038] In some embodiments, the first material can be an electron donor material (e.g., P3HT). In such embodiments, the second and third materials can be electron acceptor materials (e.g., C 61 -PCBM or C 71 -PCBM). In some embodiments, the first material can be an electron acceptor material. In such embodiments, the second and third materials can be electron donor materials. Additional exemplary electron donor materials and electron acceptor materials are described in more detail below.
[0039] The concentrations of the first and second materials in the composition can generally be adjusted as desired. For example, the composition can include at least about 0.5 wt % (e.g., at least about 0.7 wt %, at least about 0.8 wt %, at least about 0.9 wt %, or at least about 1.0 wt %) of the first material. As another example, the composition can include at least about 0.5 wt % (e.g., at least about 1.0 wt %, at least about 1.5wt %, at least about 2.0 wt %, at least about 2.5 wt %, at least about 3.0 wt %, or at least about 3.5 wt %) of the second material. In some embodiments, the concentrations can be adjusted to achieve a desired viscosity of the composition or a desired thickness of the layer to be formed.
[0040] In some embodiments, the weight ratio between the first and second materials can be at least about 0.5:1 (e.g., at least about 1:1, at least about 1.5:1, at least about 2:1, at least about 2.5:1, at least about 3:1, at least about 3.5: 1, at least about 4:1, at least about 4.5:1, or at least about 5:1).
[0041] In some embodiments, the composition further includes a solvent. For example, the solvent can be an organic solvent, such as chlorobenzene, o-dichlorobenzene, trichlorobenzene, o-xylene, m-xylene, p-xylene, toluene, mesitylene, ethylbenzene, isobutylbenzene, t-butylbenzene, α-methylnaphthalene, tetralin, N-methylpyrrolidone, methyl ethyl ketone, or acetone. In some embodiments, the solvent can be a mixture of the exemplary solvents mentioned above.
[0042] In some embodiments, the composition can be applied by a liquid-based coating process. The term “liquid-based coating process” mentioned herein refers to a process that uses a liquid-based coating composition. Examples of liquid-based coating compositions include solutions, dispersions, and suspensions.
[0043] The liquid-based coating process can be carried out by using at least one of the following processes: solution coating, ink jet printing, spin coating, dip coating, knife coating, bar coating, spray coating, roller coating, slot coating, gravure coating, flexographic printing, or screen printing. Without wishing to bound by theory, it is believed that the liquid-based coating process can be readily used in a continuous manufacturing process, such as a roll-to-roll process, thereby significantly reducing the cost of preparing a photovoltaic cell. Examples of roll-to-roll processes have been described in, for example, commonly-owned co-pending U.S. Application Publication No. 2005-0263179, the contents of which are hereby incorporated by reference.
[0044] The liquid-based coating process can be carried out at an elevated temperature (e.g., at least about 50° C., at least about 100° C., at least about 200° C., or at least about 300° C). The temperature can be adjusted depending on various factors, such as the coating process and the coating composition used. In some embodiments, when preparing a layer containing inorganic nanoparticles, the nanoparticles can be sintered at a high temperature (e.g., at least about 300° C.) to form interconnected nanoparticles. On the other hand, in certain embodiments, when a polymeric linking agent (e.g., poly(n-butyl titanate)) is added to the inorganic nanoparticles, the sintering process can be carried out at a lower temperature (e.g., below about 300° C.).
[0045] In some embodiments, when the composition contains organic first and second materials, the liquid-based coating process can be carried out by (1) dissolving or dispersing the first and second materials (e.g., P3HT and C 61 -PCBM, respectively) in a suitable solvent (e.g., chlorobenzene) to form a solution or a dispersion, (2) coating the solution or dispersion on hole carrier layer 130 , and (3) drying the coated solution or dispersion to form the intermediate layer.
[0046] In some embodiments, the composition can further include a processing additive (e.g., 1,8-diiodooctane or 1,8-dithioloctane). In some embodiments, the processing additive is selected from the group consisting of an alkane substituted with halo, thiol, CN, or COOR, R being H or C 1 -C 10 alkyl; a cyclopentadithiophene optionally substituted with C 1 -C 10 alkyl; a fluorene optionally substituted with C 1 -C 10 alkyl; a thiophene optionally substituted with C 1 -C 10 alkyl; a benzothiadiazole optionally substituted with C 1 -C 10 alkyl; a naphthalene optionally substituted with C 1 -C 10 alkyl; and a 1,2,3,4-tetrahydronaphthalene optionally substituted with C 1 -C 10 alkyl. In certain embodiments, the processing additive is an alkane (e.g., a C 6 -C 12 alkane such as an octane) substituted with Cl, Br, I, SH, CN, or COOCH 3 . Examples of suitable processing additives have been described in, for example, commonly owned co-pending U.S. Application No. 60/984,229, the entire contents of which are hereby incorporated by reference.
[0047] Typically, the processing additive is removed during the drying of the coated solution. However, in some embodiments, at least some of the processing additive remains in the intermediate layer after the drying is complete. In such embodiments, the processing additives can be at least about 0.1 wt % (e.g., at least about 1 wt %, at least about 5 wt %, or at least about 10 wt %) of photoactive layer 140.
[0048] Without wishing to be bound by theory, it is believed that, in some embodiments, the processing additive substantially dissolves one of the first and second materials (e.g., C 61 -PCBM), but does not substantially dissolve the other of the first and second materials (e.g., P3HT). As such, when the coating composition containing such a processing additive is applied to a surface to form an intermediate layer, the processing additive facilitates phase separation between the first and second materials so that an intermediate layer with a desirable morphology can be formed. Without wishing to be bound by theory, it is believed that the intermediate layer thus formed can serve as a template to form photoactive layer 140 with a desired morphology by replacing one of the first and second materials with a third material. Further, without wishing to be bound by theory, it is believed that one advantage of forming a photoactive layer through an intermediate layer with a desired morphology is that the morphology of the intermediate layer does not change substantially during any subsequent processes.
[0049] After the intermediate layer is formed, at least some of the second material can be removed from the intermediate layer to form a porous layer. In some embodiments, the removal can be carried out by contacting the intermediate layer with a suitable solvent (e.g., 1,8-diiodooctane or 1,8-dithioloctane) that substantially dissolves the second material, but does not substantially dissolve the first material. In general, the solvent can be either the same as or different from the processing additive described above.
[0050] In some embodiments, the removal can be carried out by applying a vacuum to the intermediate layer, heating the intermediate layer, or a combination thereof. For example, when the second material has a boiling point substantially lower than the first material, at least some of the second material can be removed by vacuum and/or heating (e.g., at a temperature well above the boiling of the second material but well below the boiling point of the first material) such that no significant amount of the first material is removed.
[0051] In some embodiments, the removal can be carried out during the drying of the intermediate layer, rather than after the intermediate layer is completely formed. For example, when the second material has a boiling point substantially lower than the first material, the removal can be carried out during drying at a temperature well above the boiling points of the solvent and the second material, but well below the boiling point of the first material. As such, at least some (e.g., all) of the second material is removed together with the solvent during drying to form a porous layer, while no significant amount of the first material is removed. In some embodiments, the drying is carried out under vacuum, either alone or in combination with heating.
[0052] In some embodiments, the first material can be cross-linked to form an insoluble material before or after removal of at least some of the second material. In some embodiments, the first material can include one or more cross-linkable groups (e.g., epoxy groups). In certain embodiments, the first material can include a fullerene substituted with one or more cross-linkable groups. Examples of such fullerenes have been described in commonly-owned co-pending U.S. Application Publication No. 2005-0279399, the contents of which are hereby incorporated by reference in its entirety. In certain embodiments, the first material can include an electron donor material (e.g., a polythiophene) substituted with one or more cross-linking groups. In some embodiments, the cross-linking can be carried out by subjecting the first material to an elevated temperature, moisture, and/or UV illumination. In some embodiments, a cross-linking agent can be added to the composition used to form the intermediate layer to cross-link the first material. An example of such a cross-linking agent is SILQUEST (Harwick Standard Distribution Corporation, Akron, Ohio). Without wishing to be bound by theory, it is believed that cross-linking of the first material could result in a material that is insoluble in any solvent and therefore could maintain the morphology of the first material during any subsequent processes. In certain embodiments, the first material can be thermally treated to form an insoluble material before or after removal of at least some of the second material.
[0053] In some embodiments, pores in the porous layer can have an average diameter of at least about 20 nm (e.g., at least about 50 nm or at least about 100 nm) and/or at most about 500 nm (e.g., at most about 300 nm or at most about 200 nm).
[0054] Once the porous layer is formed, a third material can be disposed into at least some of the pores to form photovoltaic layer 140 . In some embodiments, the third material can be disposed by a liquid-based coating process, such as one of the processes described above. In some embodiments, the third material and the first or second material remaining in the porous layer do not both have a solubility of at least about 0.1 mg/ml (e.g., at least about 0.5 mg/ml, or at least about 1 mg/ml, at least about 5 mg/ml, or at least about 10 mg/ml) in any solvent at about 25° C.
[0055] In some embodiments, the third material can be dissolved or dispersed in a suitable solvent to form a composition and then disposed into at least some of the pores. In certain embodiments, one or more additives can be added to facilitate the disposition of the composition into the pores, for example, by modifying its wetting properties (e.g., surface tension). Examples of such additives include TRITON X (Sigma-Aldrich, St. Louis, Mo.), SURFYNOL (Air Products and Chemicals, Inc., Allentown, Pa.), and DYNOL (Air Products and Chemicals, Inc., Allentown, Pa.). In some embodiments, a second solvent can be added to the composition to modify its wetting properties.
[0056] In some embodiments, the third material has a solubility of at most about 10 mg/ml (e.g., at most about 1 mg/ml or at most about 0.1 mg/ml) in any solvent at about 25° C. Examples of such materials include carbon nanotubes or carbon nanorods. In some embodiments, such materials can be dispersed in a suitable solvent and then disposed into at least some of the pores.
[0057] In some embodiments, photoactive layer 140 prepared by the methods described above can have at least two separated phases where at least one of the two phases has an average grain size of at least about 20 nm (e.g., at least about 50 nm or at least about 100 nm) and/or at most about 500 nm (e.g., at most about 300 nm or at most about 200 nm). Without wishing to be bound by theory, it is believed that a larger separated phase in a photoactive layer can enhance the power-conversion efficiency of the photovoltaic cell. Further, in some embodiments, the methods described above can reduce the need of post-processing (e.g., temperature annealing or solvent annealing) of photoactive layer 140 .
[0058] Without wishing to be bound by theory, it is believed that one advantage of the methods described above is that they allow the preparation of a heterojunction photoactive layer with a desired morphology even though the two semiconductor materials (e.g., two semiconductor materials that do not have sufficient solubility in a common solvent) contained in the photoactive layer would otherwise result in an unfavorable morphology. Exemplary pairs of such two materials include a water-soluble semiconductor polymer (e.g., a water-soluble polythiophene) and an organic solvent-soluble fullerene (e.g., C 61 -PCBM), an organic solvent-soluble semiconductor polymer (e.g., P3HT) and a water-soluble fullerene, an organic solvent-soluble semiconductor polymer and a water-soluble semiconductor polymer, and an organic solvent-soluble semiconductor polymer and a carbon allotrope (e.g., carbon nanotubes or carbon nanorods) that is not soluble in any solvent. Unless specified otherwise, the term “soluble” mentioned herein means that a material has a solubility of at least about 0.1 mg/ml at 25° C. in a solvent. Examples of water-soluble polymers include poly(2-(3-thienyloxy)ethanesulfonate), sodium poly(2-(4-methyl-3-thienyloxy)ethanesulfonate), and poly(2-methoxy-5-propyloxysulfonate-1,4-phenylenevinylene). Examples of organic solvent-soluble polymer are described below. Examples of water-soluble fullerenes include [11-(2,2-dimethyl-[60]fulleropyrolidin-1-yl)-undecyl]-trimethyl-ammonium and [6,6]-bis[2,4-bis(7-octanoicacid-1-oxy)formicacidbenzylester]-C61. Examples of organic solvent-soluble fullerenes include pristine C60, pristine C70, C 61 -PCBM, or C 71 -PCBM.
[0059] In general, first, second, or third material can be an electron acceptor material (e.g., an organic electron acceptor material) or an electron donor material (e.g., an organic electron donor material). In some embodiments, photoactive layer 140 formed by the methods described above contains at least an electron acceptor material and at least an electron donor material.
[0060] Examples of electron acceptor materials include fullerenes, inorganic nanoparticles, oxadiazoles, discotic liquid crystals, carbon nanorods, inorganic nanorods, polymers containing moieties capable of accepting electrons or forming stable anions (e.g., polymers containing CN groups or polymers containing CF 3 groups), and combinations thereof. In some embodiments, the electron acceptor material is a substituted fullerene (e.g., C 61 -PCBM or C 71 -PCBM). In some embodiments, the electron acceptor materials can include small molecule compounds. Examples of such small molecule electron acceptors include polycyclic aromatic hydrocarbons (e.g., perylene). In some embodiments, a combination of electron acceptor materials can be used in photoactive layer 140 .
[0061] Examples of electron donor materials include conjugated polymers, such as polythiophenes, polyanilines, polycarbazoles, polyvinylcarbazoles, polyphenylenes, polyphenylvinylenes, polysilanes, polythienylenevinylenes, polyisothianaphthanenes, polycyclopentadithiophenes, polysilacyclopentadithiophenes, polycyclopentadithiazoles, polythiazolothiazoles, polythiazoles, polybenzothiadiazoles, poly(thiophene oxide)s, poly(cyclopentadithiophene oxide)s, polythiadiazoloquinoxalines, polybenzoisothiazoles, polybenzothiazoles, polythienothiophenes, poly(thienothiophene oxide)s, polydithienothiophenes, poly(dithienothiophene oxide)s, polyfluorenes, polytetrahydroisoindoles, and copolymers thereof. In some embodiments, the electron donor material can be polythiophenes (e.g.,P3HT), polycyclopentadithiophenes (e.g., poly(cyclopentadithiophene-co-benzothiadiazole)), and copolymers thereof. In some embodiments, the electron donor materials can include small molecule compounds. Examples of such small molecule electron donors include polycyclic aromatic hydrocarbons (e.g., phthalocyanines and porphyrins). In certain embodiments, a combination of electron donor materials can be used in photoactive layer 140 .
[0062] In some embodiments, the electron donor materials or the electron acceptor materials can include a polymer having a first comonomer repeat unit and a second comonomer repeat unit different from the first comonomer repeat unit. The first comonomer repeat unit can include a cyclopentadithiophene moiety, a silacyclopentadithiophene moiety, a cyclopentadithiazole moiety, a thiazolothiazole moiety, a thiazole moiety, a benzothiadiazole moiety, a thiophene oxide moiety, a cyclopentadithiophene oxide moiety, a polythiadiazoloquinoxaline moiety, a benzoisothiazole moiety, a benzothiazole moiety, a thienothiophene moiety, a thienothiophene oxide moiety, a dithienothiophene moiety, a dithienothiophene oxide moiety, or a tetrahydroisoindoles moiety.
[0063] In some embodiments, the first comonomer repeat unit includes a cyclopentadithiophene moiety. In some embodiments, the cyclopentadithiophene moiety is substituted with at least one substituent selected from the group consisting of C 1 -C 20 alkyl, C 1 -C 20 alkoxy, C 3 -C 20 cycloalkyl, C 1 -C 20 heterocycloalkyl, aryl, heteroaryl, halo, CN, OR, C(O)R, C(O)OR, and SO 2 R; R being H, C 1 -C 20 alkyl, C 1 -C 20 alkoxy, aryl, heteroaryl, C 3 -C 20 cycloalkyl, or C 1 -C 20 heterocycloalkyl. For example, the cyclopentadithiophene moiety can be substituted with hexyl, 2-ethylhexyl, or 3,7-dimethyloctyl. In certain embodiments, the cyclopentadithiophene moiety is substituted at 4-position. In some embodiments, the first comonomer repeat unit can include a cyclopentadithiophene moiety of formula (1):
[0000]
[0000] In formula (1), each of R 1 , R 2 , R 3 , or R 4 , independently, is H, C 1 -C 20 alkyl, C 1 -C 20 alkoxy, C 3 -C 20 cycloalkyl, C 1 -C 20 heterocycloalkyl, aryl, heteroaryl, halo, CN, OR, C(O)R, C(O)OR, or SO 2 R; R being H, C 1 -C 20 alkyl, C 1 -C 20 alkoxy, aryl, heteroaryl, C 3 -C 20 cycloalkyl, or C 1 -C 20 heterocycloalkyl. For example, each of R 1 and R 2 , independently, can be hexyl, 2-ethylhexyl, or 3,7-dimethyloctyl.
[0064] An alkyl can be saturated or unsaturated and branch or straight chained. A C 1 -C 20 alkyl contains 1 to 20 carbon atoms (e.g., one, two, three, four, five, six, seven, eight, nine, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, and 20 carbon atoms). Examples of alkyl moieties include —CH 3 , —CH 2 —, —CH 2 ═CH 2 —, —CH 2 —CH═CH 2 , and branched —C 3 H 7 . An alkoxy can be branch or straight chained and saturated or unsaturated. An C 1 -C 20 alkoxy contains an oxygen radical and 1 to 20 carbon atoms (e.g., one, two, three, four, five, six, seven, eight, nine, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, and 20 carbon atoms). Examples of alkoxy moieties include —OCH 3 and —OCH═CH—CH 3 . A cycloalkyl can be either saturated or unsaturated. A C 3 -C 20 cycloalkyl contains 3 to 20 carbon atoms (e.g., three, four, five, six, seven, eight, nine, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, and 20 carbon atoms). Examples of cycloalkyl moieities include cyclohexyl and cyclohexen-3-yl. A heterocycloalkyl can also be either saturated or unsaturated. A C 3 -C 20 heterocycloalkyl contains at least one ring heteroatom (e.g., O, N, and S) and 3 to 20 carbon atoms (e.g., three, four, five, six, seven, eight, nine, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, and 20 carbon atoms). Examples of heterocycloalkyl moieties include 4-tetrahydropyranyl and 4-pyranyl. An aryl can contain one or more aromatic rings. Examples of aryl moieties include phenyl, phenylene, naphthyl, naphthylene, pyrenyl, anthryl, and phenanthryl. A heteroaryl can contain one or more aromatic rings, at least one of which contains at least one ring heteroatom (e.g., O, N, and S). Examples of heteroaryl moieties include furyl, furylene, fluorenyl, pyrrolyl, thienyl, oxazolyl, imidazolyl, thiazolyl, pyridyl, pyrimidinyl, quinazolinyl, quinolyl, isoquinolyl, and indolyl.
[0065] Alkyl, alkoxy, cycloalkyl, heterocycloalkyl, aryl, and heteroaryl mentioned herein include both substituted and unsubstituted moieties, unless specified otherwise. Examples of substituents on cycloalkyl, heterocycloalkyl, aryl, and heteroaryl include C 1 -C 20 alkyl, C 3 -C 20 cycloalkyl, C 1 -C 20 alkoxy, aryl, aryloxy, heteroaryl, heteroaryloxy, amino, C 1 -C 10 alkylamino, C 1 -C 20 dialkylamino, arylamino, diarylamino, hydroxyl, halogen, thio, C 1 -C 10 alkylthio, arylthio, C 1 -C 10 alkylsulfonyl, arylsulfonyl, cyano, nitro, acyl, acyloxy, carboxyl, and carboxylic ester. Examples of substituents on alkyl include all of the above-recited substituents except C 1 -C 20 alkyl. Cycloalkyl, heterocycloalkyl, aryl, and heteroaryl also include fused groups.
[0066] The second comonomer repeat unit can include a benzothiadiazole moiety, a thiadiazoloquinoxaline moiety, a cyclopentadithiophene oxide moiety, a benzoisothiazole moiety, a benzothiazole moiety, a thiophene oxide moiety, a thienothiophene moiety, a thienothiophene oxide moiety, a dithienothiophene moiety, a dithienothiophene oxide moiety, a tetrahydroisoindole moiety, a fluorene moiety, a silole moiety, a cyclopentadithiophene moiety, a fluorenone moiety, a thiazole moiety, a selenophene moiety, a thiazolothiazole moiety, a cyclopentadithiazole moiety, a naphthothiadiazole moiety, a thienopyrazine moiety, a silacyclopentadithiophene moiety, an oxazole moiety, an imidazole moiety, a pyrimidine moiety, a benzoxazole moiety, or a benzimidazole moiety. In some embodiments, the second comonomer repeat unit is a 3,4-benzo-1,2,5-thiadiazole moiety.
[0067] In some embodiments, the second comonomer repeat unit can include a benzothiadiazole moiety of formula (2), a thiadiazoloquinoxaline moiety of formula (3), a cyclopentadithiophene dioxide moiety of formula (4), a cyclopentadithiophene monoxide moiety of formula (5), a benzoisothiazole moiety of formula (6), a benzothiazole moiety of formula (7), a thiophene dioxide moiety of formula (8), a cyclopentadithiophene dioxide moiety of formula (9), a cyclopentadithiophene tetraoxide moiety of formula (10), a thienothiophene moiety of formula (11), a thienothiophene tetraoxide moiety of formula (12), a dithienothiophene moiety of formula (13), a dithienothiophene dioxide moiety of formula (14), a dithienothiophene tetraoxide moiety of formula (15), a tetrahydroisoindole moiety of formula (16), a thienothiophene dioxide moiety of formula (17), a dithienothiophene dioxide moiety of formula (18), a fluorene moiety of formula (19), a silole moiety of formula (20), a cyclopentadithiophene moiety of formula (21), a fluorenone moiety of formula (22), a thiazole moiety of formula (23), a selenophene moiety of formula (24), a thiazolothiazole moiety of formula (25), a cyclopentadithiazole moiety of formula (26), a naphthothiadiazole moiety of formula (27), a thienopyrazine moiety of formula (28), a silacyclopentadithiophene moiety of formula (29), an oxazole moiety of formula (30), an imidazole moiety of formula (31), a pyrimidine moiety of formula (32), a benzoxazole moiety of formula (33), or a benzimidazole moiety of formula (34):
[0000]
[0000] In the above formulas, each of X and Y, independently, is CH 2 , O, or S; each of R 5 and R 6 , independently, is H, C 1 -C 20 alkyl, C 1 -C 20 alkoxy, C 3 -C 20 cycloalkyl, C 1 -C 20 heterocycloalkyl, aryl, heteroaryl, halo, CN, OR, C(O)R, C(O)OR, or SO 2 R, in which R is H, C 1 -C 20 alkyl, C 1 -C 20 alkoxy, aryl, heteroaryl, C 3 -C 20 cycloalkyl, or C 1 -C 20 heterocycloalkyl; and each of R 7 and R 8 , independently, is H, C 1 -C 20 alkyl, C 1 -C 20 alkoxy, aryl, heteroaryl, C 3 -C 20 cycloalkyl, or C 3 -C 20 heterocycloalkyl. In some embodiments, the second comonomer repeat unit includes a benzothiadiazole moiety of formula (2), in which each of R 5 and R 6 is H.
[0068] The second comonomer repeat unit can include at least three thiophene moieties. In some embodiments, at least one of the thiophene moieties is substituted with at least one substituent selected from the group consisting of C 1 -C 20 alkyl, C 1 -C 20 alkoxy, aryl, heteroaryl, C 3 -C 20 cycloalkyl, and C 3 -C 20 heterocycloalkyl. In certain embodiments, the second comonomer repeat unit includes five thiophene moieties.
[0069] The polymer can further include a third comonomer repeat unit that contains a thiophene moiety or a fluorene moiety. In some embodiments, the thiophene or fluorene moiety is substituted with at least one substituent selected from the group consisting of C 1 -C 20 alkyl, C 1 -C 20 alkoxy, aryl, heteroaryl, C 3 -C 20 cycloalkyl, and C 3 -C 20 heterocycloalkyl.
[0070] In some embodiments, the polymer can be formed by any combination of the first, second, and third comonomer repeat units. In certain embodiments, the polymer can be a homopolymer containing any of the first, second, and third comonomer repeat units.
[0071] In some embodiments, the polymer can be
[0000]
[0000] n which n can be an integer greater than 1.
[0072] In some embodiments, the electron donor or acceptor material can include a polymer containing at least one of the following two moieties:
[0000]
[0000] For example, the polymer can be
[0000]
[0073] The monomers for preparing the polymers mentioned herein may contain a non-aromatic double bond and one or more asymmetric centers. Thus, they can occur as racemates and racemic mixtures, single enantiomers, individual diastereomers, diastereomeric mixtures, and cis- or trans- isomeric forms. All such isomeric forms are contemplated.
[0074] The polymers described above can be prepared by methods known in the art, such as those described in commonly owned co-pending U.S. application Ser. No. 11/601,374, the contents of which are hereby incorporated by reference. For example, a copolymer can be prepared by a cross-coupling reaction between one or more comonomers containing two alkylstannyl groups and one or more comonomers containing two halo groups in the presence of a transition metal catalyst. As another example, a copolymer can be prepared by a cross-coupling reaction between one or more comonomers containing two borate groups and one or more comonomers containing two halo groups in the presence of a transition metal catalyst. The comonomers can be prepared by the methods know in the art, such as those described in U.S. patent application Ser. No. 11/486,536, Coppo et al., Macromolecules 2003, 36, 2705-2711, and Kurt et al., J. Heterocycl. Chem. 1970, 6, 629, the contents of which are hereby incorporated by reference.
[0075] Without wishing to be bound by theory, it is believed that an advantage of the polymers described above is that their absorption wavelengths shift toward the red and near IR regions (e.g., 650-800 nm) of the electromagnetic spectrum, which is not accessible by most other conventional polymers. When such a polymer is incorporated into a photovoltaic cell together with a conventional polymer, it enables the cell to absorb the light in this region of the spectrum, thereby increasing the current and efficiency of the cell.
[0076] Generally, photoactive layer 140 is sufficiently thick to be relatively efficient at absorbing photons impinging thereon to form corresponding electrons and holes, and sufficiently thin to be relatively efficient at transporting the holes and electrons. In certain embodiments, photoactive layer 140 is at least 0.05 micron (e.g., at least about 0.1 micron, at least about 0.2 micron, at least about 0.3 micron) thick and/or at most about one micron (e.g., at most about 0.5 micron, at most about 0.4 micron) thick. In some embodiments, photoactive layer 140 is from about 0.1 micron to about 0.2 micron thick.
[0077] Turning to other components of photovoltaic cell 100 , substrate 110 is generally formed of a transparent material. As referred to herein, a transparent material is a material which, at the thickness used in a photovoltaic cell 100 , transmits at least about 60% (e.g., at least about 70%, at least about 75%, at least about 80%, at least about 85%) of incident light at a wavelength or a range of wavelengths used during operation of the photovoltaic cell. Exemplary materials from which substrate 110 can be formed include polyethylene terephthalates, polyimides, polyethylene naphthalates, polymeric hydrocarbons, cellulosic polymers, polycarbonates, polyamides, polyethers, and polyether ketones. In certain embodiments, the polymer can be a fluorinated polymer. In some embodiments, combinations of polymeric materials are used. In certain embodiments, different regions of substrate 110 can be formed of different materials.
[0078] In general, substrate 110 can be flexible, semi-rigid or rigid (e.g., glass). In some embodiments, substrate 110 has a flexural modulus of less than about 5,000 megaPascals (e.g., less than about 1,000 megaPascals or less than about 5,00 megaPascals). In certain embodiments, different regions of substrate 110 can be flexible, semi-rigid, or inflexible (e.g., one or more regions flexible and one or more different regions semi-rigid, one or more regions flexible and one or more different regions inflexible).
[0079] Typically, substrate 110 is at least about one micron (e.g., at least about five microns, at least about 10 microns) thick and/or at most about 1,000 microns (e.g., at most about 500 microns thick, at most about 300 microns thick, at most about 200 microns thick, at most about 100 microns, at most about 50 microns) thick.
[0080] Generally, substrate 110 can be colored or non-colored. In some embodiments, one or more portions of substrate 110 is/are colored while one or more different portions of substrate 110 is/are non-colored.
[0081] Substrate 110 can have one planar surface (e.g., the surface on which light impinges), two planar surfaces (e.g., the surface on which light impinges and the opposite surface), or no planar surfaces. A non-planar surface of substrate 110 can, for example, be curved or stepped. In some embodiments, a non-planar surface of substrate 110 is patterned (e.g., having patterned steps to form a Fresnel lens, a lenticular lens or a lenticular prism).
[0082] Electrode 120 is generally formed of an electrically conductive material. Exemplary electrically conductive materials include electrically conductive metals, electrically conductive alloys, electrically conductive polymers, and electrically conductive metal oxides. Exemplary electrically conductive metals include gold, silver, copper, aluminum, nickel, palladium, platinum, and titanium. Exemplary electrically conductive alloys include stainless steel (e.g., 332 stainless steel, 316 stainless steel), alloys of gold, alloys of silver, alloys of copper, alloys of aluminum, alloys of nickel, alloys of palladium, alloys of platinum and alloys of titanium. Exemplary electrically conducting polymers include polythiophenes (e.g., doped poly(3,4-ethylenedioxythiophene) (doped PEDOT)), polyanilines (e.g., doped polyanilines), polypyrroles (e.g., doped polypyrroles). Exemplary electrically conducting metal oxides include indium tin oxide, fluorinated tin oxide, tin oxide and zinc oxide. In some embodiments, combinations of electrically conductive materials are used.
[0083] In some embodiments, electrode 120 can include a mesh electrode. Examples of mesh electrodes are described in co-pending U.S. Patent Application Publication Nos. 20040187911 and 20060090791, the entire contents of which are hereby incorporated by reference.
[0084] Hole carrier layer 130 is generally formed of a material that, at the thickness used in photovoltaic cell 100 , transports holes to electrode 120 and substantially blocks the transport of electrons to electrode 120 . Examples of materials from which layer 130 can be formed include polythiophenes (e.g., PEDOT), polyanilines, polycarbazoles, polyvinylcarbazoles, polyphenylenes, polyphenylvinylenes, polysilanes, polythienylenevinylenes, polyisothianaphthanenes, and copolymers thereof. In some embodiments, hole carrier layer 130 can include combinations of hole carrier materials.
[0085] In general, the thickness of hole carrier layer 130 (i.e., the distance between the surface of hole carrier layer 130 in contact with photoactive layer 140 and the surface of electrode 120 in contact with hole carrier layer 130 ) can be varied as desired. Typically, the thickness of hole carrier layer 130 is at least 0.01 micron (e.g., at least about 0.05 micron, at least about 0.1 micron, at least about 0.2 micron, at least about 0.3 micron, or at least about 0.5 micron) and/or at most about five microns (e.g., at most about three microns, at most about two microns, or at most about one micron). In some embodiments, the thickness of hole carrier layer 130 is from about 0.01 micron to about 0.5 micron.
[0086] Optionally, photovoltaic cell 100 can include a hole blocking layer 150 . The hole blocking layer is generally formed of a material that, at the thickness used in photovoltaic cell 100 , transports electrons to electrode 160 and substantially blocks the transport of holes to electrode 160 . Examples of materials from which the hole blocking layer can be formed include LiF, metal oxides (e.g., zinc oxide, titanium oxide), and amines (e.g., primary, secondary, or tertiary amines). Examples of amines suitable for use in a hole blocking layer have been described, for example, in co-pending U.S. Provisional Application Ser. No. 60/926,459, the entire contents of which are hereby incorporated by reference.
[0087] Without wishing to be bound by theory, it is believed that when photovoltaic cell 100 includes a hole blocking layer made of amines, the hole blocking layer can facilitate the formation of ohmic contact between photoactive layer 140 and electrode 160 , thereby reducing damage to photovoltaic cell 100 resulted from such exposure.
[0088] Typically, hole blocking layer 150 is at least 0.02 micron (e.g., at least about 0.03 micron, at least about 0.04 micron, at least about 0.05 micron) thick and/or at most about 0.5 micron (e.g., at most about 0.4 micron, at most about 0.3 micron, at most about 0.2 micron, at most about 0.1 micron) thick.
[0089] Electrode 160 is generally formed of an electrically conductive material, such as one or more of the electrically conductive materials described above. In some embodiments, electrode 160 is formed of a combination of electrically conductive materials. In certain embodiments, electrode 160 can be formed of a mesh electrode.
[0090] In general, each of electrode 120 , hole carrier layer 130 , hole blocking layer 150 , and electrode 160 can be prepared by a liquid-based coating process, such as one of the processes described above.
[0091] In some embodiments, when a layer (e.g., one of layers 120 , 130 , 150 , and 160 ) includes inorganic semiconductor nanoparticles, the liquid-based coating process can be carried out by (1) mixing the nanoparticles with a solvent (e.g., an aqueous solvent or an anhydrous alcohol) to form a dispersion, (2) coating the dispersion onto a substrate, and (3) drying the coated dispersion. In certain embodiments, a liquid-based coating process for preparing a layer containing inorganic metal oxide nanoparticles can be carried out by (1) dispersing a precursor (e.g., a titanium salt) in a suitable solvent (e.g., an anhydrous alcohol) to form a dispersion, (2) coating the dispersion on a photoactive layer, (3) hydrolyzing the dispersion to form an inorganic semiconductor nanoparticles layer (e.g., a titanium oxide nanoparticles layer), and (4) drying the inorganic semiconductor material layer. In certain embodiments, the liquid-based coating process can be carried out by a sol-gel process.
[0092] In general, the liquid-based coating process used to prepare a layer containing an organic semiconductor material can be the same as or different from that used to prepare a layer containing an inorganic semiconductor material. In some embodiments, when a layer (e.g., one of layers 120 , 130 , 150 , and 160 ) includes an organic semiconductor material, the liquid-based coating process can be carried out by mixing the organic semiconductor material with a solvent (e.g., an organic solvent) to form a solution or a dispersion, coating the solution or dispersion on a substrate, and drying the coated solution or dispersion.
[0093] Substrate 170 can be identical to or different from substrate 110 . In some embodiments, substrate 170 can be formed of one or more suitable polymers, such as the polymers used in substrate 110 described above.
[0094] In general, during use, light can impinge on the surface of substrate 110 , and pass through substrate 110 , electrode 120 , and hole carrier layer 130 . The light then interacts with photoactive layer 140 , causing electrons to be transferred from an electron donor material to an electron acceptor material. The electron acceptor material then transmits the electrons through intermediate layer 150 to electrode 160 , and the electron donor material transfers holes through hole carrier layer 130 to electrode 120 . Electrode 160 and electrode 120 are in electrical connection via an external load so that electrons pass from electrode 160 , through the load, and to electrode 120 .
[0095] While certain embodiments have been disclosed, other embodiments are also possible.
[0096] In some embodiments, photovoltaic cell 100 includes a cathode as a bottom electrode and an anode as a top electrode. In some embodiments photovoltaic cell 100 can also include an anode as a bottom electrode and a cathode as a top electrode.
[0097] In some embodiments, photovoltaic cell 100 can include the layers shown in FIG. 1 in a reverse order. In other words, photovoltaic cell 100 can include these layers from the bottom to the top in the following sequence: a substrate 170 , an electrode 160 , a hole blocking layer 150 , a photoactive layer 140 , a hole carrier layer 130 , an electrode 120 , and a substrate 110 .
[0098] While photovoltaic cells have been described above, in some embodiments, the compositions and methods described herein can be used in tandem photovoltaic cells. Examples of tandem photovoltaic cells have been described in, for example, commonly owned co-pending U.S. Application Publication No. 2007-0181179 and U.S. application Ser. No. 11/734,093, the entire contents of which are hereby incorporated by reference.
[0099] In some embodiments, multiple photovoltaic cells can be electrically connected to form a photovoltaic system. As an example, FIG. 2 is a schematic of a photovoltaic system 200 having a module 210 containing photovoltaic cells 220 . Cells 220 are electrically connected in series, and system 200 is electrically connected to a load 230 . As another example, FIG. 3 is a schematic of a photovoltaic system 300 having a module 310 that contains photovoltaic cells 320 . Cells 320 are electrically connected in parallel, and system 300 is electrically connected to a load 330 . In some embodiments, some (e.g., all) of the photovoltaic cells in a photovoltaic system can have one or more common substrates. In certain embodiments, some photovoltaic cells in a photovoltaic system are electrically connected in series, and some of the photovoltaic cells in the photovoltaic system are electrically connected in parallel.
[0100] While photovoltaic cells have been described above, in some embodiments, the compositions and methods described herein can be used to prepare a photoactive layer in other electronic devices and systems. For example, they can be used prepare a photoactive layer in suitable organic semiconductive devices, such as field effect transistors, photodetectors (e.g., IR detectors), photovoltaic detectors, imaging devices (e.g., RGB imaging devices for cameras or medical imaging systems), light emitting diodes (LEDs) (e.g., organic LEDs or IR or near IR LEDs), lasing devices, conversion layers (e.g., layers that convert visible emission into IR emission), amplifiers and emitters for telecommunication (e.g., dopants for fibers), storage elements (e.g., holographic storage elements), and electrochromic devices (e.g., electrochromic displays).
[0101] Other embodiments are in the claims. | Methods of forming a photoactive layer, as well as related compositions, photovoltaic cells, and photovoltaic modules, are disclosed. | 7 |
RELATED APPLICATION DATA
This application is based on and claims the benefit of U.S. Provisional Patent Application No. 60/478,480 filed on Jun. 13, 2003, the disclosure of which is incorporated herein by this reference.
STATEMENT OF GOVERNMENT FUNDING
The United States Government provided financial assistance for this project through the National Science Foundation under Grant No. DMR 0221993 and through the Army Research Office Grant No. DAA 19-00-0-0471. Therefore, the United States Government may own certain rights to this invention.
BACKGROUND
This invention relates generally to semiconductor materials and, more particularly, to doping and superdoping in situ a broad family of Si-based semiconductors such as Ge, SnGe, SiGe, and SiGeSn with As, P, and Sb (Group V element).
It has been known for many years—on theoretical grounds—that the SnGe alloy system and the SiGeSn alloy system should have properties that would be very beneficial in microelectronic and optoelectronic devices. This has stimulated intense experimental efforts to grow such compounds. For many years the resulting material quality has been incompatible with device applications. Recently, however, we successfully synthesized device-quality SnGe alloys directly on Si substrates. See M. Bauer, J. Taraci, J. Tolle A. V. G Chizmeshya, S. Zollner, J. Menendez, D. J. Smith and J. Kouvetakis, Appl. Phys. Lett 81, 2992 (2002); M. R. Bauer, J. Kouvetakis, D. J. Smith and J. Menendez, Solid State Commun. 127, 355 (2003); M. R. Bauer, P. Crozier, A. V. G Chizmeshya and J. D. Smith and J. Kouvetakis Appl. Phys. Lett. 83, 3489 (2003), which are incorporated herein by this reference.
In order to fabricate devices using these materials, however, it is necessary to dope thin films of the materials with donor and acceptor elements, such as B, P, As and Sb. Previously known methods for doping Si-based semiconductors with As or P have significant limitations. Typically n-doping is performed using a molecular source approach or by ion implantation using solid sources of the dopant elements. Ion implantation has advantages such as relatively low processing temperatures and the short processing times. However, it also has some major disadvantages, such as significant substrate damage and composition gradients across the film. For the thermodynamically unstable Sn—Ge lattice the re-growth temperatures, that are required to repair the implantation damage of the crystal, may exceed the temperature stability range of the film, resulting in phase segregation and precipitation of Sn. In addition, with ion implantation there are limits as to how much dopant can be introduced into the structure. Ion implantation methods and conventional CVD of the well known PH 3 and AsH 3 analogs require severe and often hostile processing conditions and are expected to be incompatible with the properties and stability range of the relatively fragile Ge—Sn lattice. In addition PH 3 and AsH 3 are highly toxic and in fact can be lethal in relatively small doses.
There is a need, therefore, for a method of incorporating appropriate concentrations of activated atoms into the lattice of the Ge—Sn system and in Ge 1-x-y Sn x E y (E=P, As, Sb) semiconductors and related Si—Ge—Sn—E and Si—Ge—E analogs. It is an object of the present invention to provide such a method.
It is another object of the present invention to such a method that is practical to implement.
Additional objects and advantages of the invention will be set forth in the description that follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by the instrumentalities and combinations pointed out herein.
SUMMARY OF THE INVENTION
To achieve the foregoing objects, and in accordance with the purposes of the invention as embodied and broadly described in this document, we provide a novel process for incorporating group V atoms such as P, As and Sb into. Ge—Sn materials and other group IV semiconductors. The process includes synthesizing a compound having the formula E(GeH 3 ) 3 wherein E is selected from the group consisting of arsenic (As), antimony (Sb) and phosphorus (P). According to a preferred approach, GeH 3 Br with [(CH 3 ) 3 Si] 3 E are combined under conditions whereby E(GeH 3 ) 3 is obtained. The E(GeH 3 ) 3 is then purified by trap-to-trap fractionation. E(GeH 3 ) 3 can be obtained with a yield from about 70% to about 76%.
According to another aspect of the invention, a method for doping a region of a semiconductor material in a chemical vapor deposition reaction chamber is described. The method includes introducing into the chamber a gaseous precursor having the formula E(GeH 3 ) 3 , wherein E is selected from the group consisting of arsenic (As), antimony (Sb) and phosphorus (P). The semiconductor material can comprise germanium (Ge), SiGeSn, SiGe or SnGe.
According to another aspect of the invention, a method for depositing a doped epitaxial Ge—Sn layer on a substrate in a chemical vapor deposition reaction chamber is described. The method includes introducing into the chamber a gaseous precursor comprising SnD 4 mixed in H 2 under conditions whereby the epitaxial Ge—Sn layer is formed on the substrate, including a silicon substrate, and introducing into the chamber a gaseous precursor having the formula E(GeH 3 ) 3 , wherein E is selected from the group consisting of arsenic (As), antimony (Sb) and phosphorus (P). The gaseous precursor is introduced at a temperature in a range of about 250° C. to about 350° C.
BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate the presently preferred methods and embodiments of the invention. Together with the general description given above and the detailed description of the preferred methods and embodiments given below, they serve to explain the principles of the invention.
FIG. 1 shows a typical gas-phase FTIR spectrum of trigermylarsine, (H 3 Ge) 3 As showing sharp absorption bands at 2077 (Ge—H stretching), 873, 829, 785 (Ge—H deformation), 530 and 487 cm −1 (Ge—H rocking).
FIG. 2 shows the PIXE spectrum of a Ge—Sn:As film grown according to the present invention.
FIG. 3 is a low energy SIMS profile for Ge—Sn:As (3 at % As concentration) grown according to the present invention.
FIG. 4 shows aligned and random RBS spectra represented by the low and high intensity traces, respectively, of a 120 nm Ge 0.97 Sn 0.03 film doped with As grown on Si according to the method of the present invention.
FIG. 5 is a low energy SIMS profile of a Sn 0.03 Ge 0.97 sample doped with As according to the present invention.
FIG. 6 is a cross sectional view of a layer of GeSn;As/Si(100) showing a highly uniform film thickness and smooth and continuous surface morphology.
FIG. 7 is a magnified view of the GeSn;As/Si(100) heterostrucure grown according to the invention, showing that most of the defects are concentrated near the film/substrate interface while the upper portion of the layer remains relatively defect free. The inset shows an electron diffraction pattern indicating a highly aligned and epitaxial GeSn:As layer on Si.
FIG. 8 is a high resolution image of the film/substrate interface of a Ge 0.97 Sn 0.03 :As film grown on Si (100). The image is in the (110) projection and shows high quality heteroepitaxial character.
FIG. 9 is an atomic force microscope image of the a Ge 0.97 Sn 0.03 :As film grown on Si (100) according to the present invention.
DESCRIPTION
In this specification, we describe new synthesis strategies, based on novel molecular hydride sources, to incorporate Group V atoms such as P, As and Sb into the diamond lattice of Group IV semiconductor materials, including the Ge and Si—Ge and SiGeSn systems These sources are the trigermylphosphine P(GeH 3 ) 3 , trigermylarsine As(GeH 3 ) 3 , and trigermylstibine Sb(GeH 3 ) 3 family of compounds. These molecular precursors are stable and volatile at room temperature and possess the necessary reactivity to dissociate completely at growth conditions for Ge, SiGe, SnGe or SiGeSn systems, via elimination of benign and stable byproducts that do not contaminate the film. The byproduct is the H 2 molecule, indicating that the precursors must be carbon-free inorganic hydrides that incorporate the desired elements P, As and Sb within a Ge coordination environment The reactions of these molecules with appropriate concentrations of SnD 4 and/or (GeH 3 ) 2 will generate Ge—Sn compositions doped with the desired levels of a group V element.
According to one aspect of our invention, the As(GeH 3 ) 3 , Sb(GeH 3 ) 3 , and P(GeH 3 ) 3 hydride precursors are prepared using a novel high-yield method. These precursors are then used in a novel doping method that involves in situ incorporation of the dopant atoms into the Ge, SiGe, SnGe or SiGeSn system. The hydride compounds are co-deposited with appropriate Si/Ge/Sn sources to form Sn—Ge or Si—Ge—Sn doped with the appropriate carrier type. In the case of As, we have succeeded in increasing the free carrier concentration by making and using precursors with direct Ge—As bonds, such as As(GeH 3 ) 3 . This unique species is an ideal molecular source for low temperature, low cost, high efficiency doping applications that are conducted via simple, single-step processes. The compound is carbon-free inorganic hydride and is designed to furnish a basic structural unit comprised of the dopant atom surrounded by three Ge atoms. This arrangement produces homogeneous, substitution of dopant atoms at high concentrations without clustering or segregation.
The P(GeH 3 ) 3 , As(GeH 3 ) 3 , and Sb(GeH 3 ) 3 precursors can be used to dope functional materials such as Ge, SiGe, SnGe or SiGeSn at levels that cannot be achieved by conventional methods. We can increase the free carrier concentration by using these precursors with direct Ge—P, Ge—As, and Ge—Sb bonds and atomic arrangements that are structurally compatible with the Ge—Sn lattice. Previous reports provide only preliminary results of the synthesis and some basic physical properties of these P(GeH 3 ) 3 , As(GeH 3 ) 3 , and Sb(GeH 3 ) 3 compounds. See S. Cradock, E. A. V. Ebsorth, G. Davidson, L. A Woodard, J. Chem. Soc. A, 8, 1229, (1967); D. W. H. Rankin, A. G. E. Robiet, G. M. Sheldrick, 5 Beagley, T. G. HeMit, J. Inorg. Nucl. Chem., 31, 2351, (1969); E. A. V. Ebswort, D. J. Hutchison, J. Douglas, D. W. H. Rankin, J. Chem. Res., Synop, 12, 393, (1980); E. A. V. Ebsworth, D. W. H. Rankin, G. M. Sheldrick, J. Chem. Soc. A, 11, 2828, (1968). D. E. Wingeleth, A. D. Norman, Phosphonus Sulfur, 39, 123, (1988). These previously-described procedures, however, provide low yields and in certain cases only traces of the desired product are produced. In addition these procedures are exceedingly difficult and involve steps that can be potentially dangerous especially for the scaling up phase of the work to produce industrial-scale quantities of the desired compound. Our work demonstrates new and practical methods to prepare, isolate, purify and handle these molecules in sufficient quantities to make them useful as chemical reagents as well as CVD gas sources for semiconductor applications.
Preparation of (GeH 3 ) 3 P, (Ge H 3 ) 3 As, and (Ge H 3 ) 3 Sb for Dopant Applications
Conventional n-doping of semiconductor materials with P or As atoms is performed by use of molecular PH 3 and AsH 3 (the SbH 3 analog is unstable) or by ion implantation using solid sources of the elements. As discussed above, ion implantation causes significant substrate damage and composition gradients across the film. For the thermodynamically unstable Sn—Ge lattice, the re-growth temperatures that will be needed to repair the implantation damage of the Sn—Ge crystal may exceed the temperature stability range of the film, resulting in phase segregation and precipitation of Sn. Therefore, for doping of the Sn—Ge lattice it is desirable to use a low-temperature molecular source approach since the introduction of the dopant takes place in situ during film growth and as host Ge—Sn the lattice is generated.
Using a typical growth process conducted by either gas-source molecular beam epitaxy (GS-MBE) or chemical vapor deposition (CVD), we chose to co-deposit a compound with the general formula E(GeH 3 ) 3 (E=P, As, or Sb) along with the host Ge—Sn material. We determined that this growth reaction would eliminate hydrogen and generate in situ the Ge 3 E molecular core, which contains the dopant atom B surrounded by three Go atoms. This arrangement represents a simple compositional and structural building block of the host lattice. Using the Ge 3 E core as the building block would also completely exclude formation of undesirable E-E bonding arrangements that may lead to clustering or segregation of the E dopant species. Thus we believed this new approach would be most likely to yield a highly homogeneous random distribution of the dopant at distinct atomic sites throughout the film. Furthermore, the doping levels could be precisely controlled by careful adjustment of the flux rate of the precursor during the course of the layer growth. An important benefit of As(GeH 3 ) 3 [or P(GeH 3 ) 3 ] is its higher reactivity compared to AsH 3 , which allows lower depositions temperatures than those employed in conventional CVD doping processes utilizing AsH 3 and related hydrides of phosphorus.
Numerous publications in the literature deal with synthesis, properties and reactions of the compounds (Me 3 Si) 3 E, (Me 3 Ge) 3 E, (Me 3 Sn) 3 E, and Ne 3 Pb) 3 E (E=P, As or Sb), which are the organometallic analogs of the desired precursors. See G. A. Forsyth, D. W. H. Rankin, H. E. Robertson, J. Mol. Struct. 239, 209, (1990); H. Schumann, H. J. Kroth, Z. Naturforsch., B: Anorg. Chem., Org. Chem. 32B, 523, (1977); G. Becker, H. Freudenblum, O. Mundt, M. Reti, M. Sachs, Synthetic Methods of Organometallic and Inorganic Chemistry, 3, 193, (1996); S. Schulz, M. Nieger, J. of Organomet. Chem. 570, 275, (1998); H. Schumann, U. Frank, W. W. Du Mont, F. Marschner, J. Organomet. Chem, 222, 217, (1981); M. Ates, H. J. Breunig, M. Denker, Phosphous, Sulfur Silicon Relate. Elem. 102, 287, (1995); H. Schumann, A. Roth, O. Stelzer, M. Schmidt, Inorg. Nucl. Chem. Lett. 2, 311, (1986). These materials have been widely utilized as common reagents in classical metathesis reactions to produce numerous molecular systems that incorporate the (e 3 Si) 2 E, (Me 3 Ge) 2 E, and (Me 3 Sn) 2 E ligands. However, there has been relatively little activity associated with the corresponding hydrides (which are completely free of strong C—H bonds that introduce carbon contaminants in the films) despite their potential importance as precursors for deposition of novel microelectronic and optoelectronic materials.
The (SiH 3 ) 3 E family of molecules has been synthesized and their properties have been investigated. See G. Davidson, L. A. Woodward, E. A. V. Ebsworth, G. M; Sheldrick, Spectrochim. Acta, Part A, 23, 2609, (1967); B. Beagley, A. G. Robiette, G. M. Sheldrick, Chem. Commun, 12, 601, (1967); A. Blake, B. A. V. Ebsworth, S. G. D. Henderson, Acta Crystallogr., Sect. C. Cryst. Struct. Commun, C47, 489, (1991); H. Siebert, J. Eints, J. Mol. Struct. 4, 23, (1969); D. C. McKean, Spectrochim. Acta, Part A, 24, 1253, (1968); J. B. Drake, J. Simpson, J. Chem. Soc. A. 5 1039, (1968). The high reactivity of the Si—H bonds and the absence of carbon from the molecular architecture indicated to us that these compounds could be ideal sources for low temperature depositions of semiconductors doped with P and As. The known methods for synthesizing these compounds, however, are complex and require use and manipulation of highly toxic, explosive and pyrophoric reagents such as PH 3 , AsH 3 and KPH 2 . In addition, the reported reaction yields are too low to even be considered usefull for routine laboratory applications. Thus, we determined that the synthetic routes of these compounds could not be viable for large scale industrial use.
On the other hand, there have been very few reports concerning the germaniun analogs (GeH 3 ) 3 E. See S. Cradock, E. A. V. Ebsorth, G. Davidson, L. A. Woodard, J. Chem. Soc. A, 8, 1229, (1967); D. W. H. Rankin, A. G. E. Robiet, G. M. Sheldrick, 5 Beagley, T. G. Hewit, J. Inorg. Nucl. Chem., 31, 2351, (1969); E. A. V. Ebswort, D. J. Hutchison, J. Douglas, D. W. H. Rankin, J. Chem. Res., Synop, 12, 393, (1980); E. A. V. Ebsworth, D. W. H. Rankin, G. M. Sheldrick, J. Chem. Soc. A, 11, 2828, (1968); D. E. Wingeleth, A. D. Norman, Phosphorus Sulfur, 39, 123, (1988). These papers describe initial preparation methods and preliminary identifications of such compounds. However, the yields obtained and the experimental synthetic procedures described are not viable for industrial or laboratory applications. Moreover, we found no report describing the tin (SnH 3 ) 3 Sn and lead (PbH 3 ) 3 Pb species. We decided to investigate (GeH 3 ) 3 P, (GeH 3 ) 3 As, (GeH 3 ) 3 Sb as desirable compounds for the synthesis of Ge 1-x-y Sn x P(As,Sb) y systems.
(GeH 3 ) 3 P has been previously obtained by treating a small excess of GeH 3 Br with (SiH 3 ) 3 P as illustrated by the equation:
3 GeH 3 Br+(SiH 3 ) 3 P→3SiH 3 Br+(GeH 3 ) 3 P
No yield was reported and the product was characterized by hydrogen analysis, 1 H and 31 P NMR, IR and mass spectroscopy. (GeH 3 ) 3 P was described as a colorless liquid with a melting point of −83.8° C. and a vapor pressure of 1 mmHg at 0° C. See S. Cradock, B. A. V. Ebsorth, G. Davidson, L. A. Woodard, J. Chem. Soc. A, 8, 1229, (1967); D. W. H. Rankin, A. G. E. Robiet, G. M. Sheldrick, 5 Beagley, T. G. Hewit, J. Inorg. Nucl. Chem., 31, 2351. Before the method of our invention, the (GeH 3 ) 3 As and (GeH 3 ) 3 Sb compounds were prepared in low yields by the reaction of bromogermane with the corresponding silyl compounds (which as indicated above are difficult to produce in sufficient yields to be practical reagents for routine laboratory synthesis). See E. A. V. Ebsworth, D. W. H. Rankin, G. M. Shelcick, J. Chem. Soc. A, 11, 2828, (1968). (GeH 3 ) 3 As and (GeH 3 ) 3 Sb were identified and characterized by NMR, IR, and Raman spectroscopies. These molecules were found to decompose very slowly, over time, at room temperature to give germane and an unidentified involatile substance. Their vapor pressures were not reported but there was mention of distilling the liquids onto CsBr plates to obtain IR spectra, indicating that they are sufficiently volatile to allow significant mass transport under vacuum.
(GeH 3 ) 3 P has also been synthesized by the redistribution reaction of silylphosphines and germylphosphines in the presence of B 5 H 9 , as described by Wimgeleth, A. D. Norman, Phosphorus Sulfr, 39, 123, (1988). In these reactions, B 5 H 9 and GeH 3 PH 2 were intermixed in the gas phase at room temperature and the trigermylphosphine (20% yield) was found in the reaction vessel along with PH 3 , GeH 4 , and unreacted starting material.
According to a preferred method of the present invention, we provide a new, convenient and high yield method to prepare (GeH 3 ) 3 P, (Ge H 3 ) 3 As, and (Ge H 3 ) 3 Sb. This trigermyl family of compounds is safer and easier to handle and store than reagents such as PH 3 , AsH 3 and KPH 2 . This new method is based on the general reaction described by the equation below, and provides large concentrations of the final product (>70%) to allow thorough characterization, purification and ultimately routine application in film growth. According to this method, the more common and relatively inexpensive trimethylsilyl derivatives [(CH 3 ) 3 Si)] 3 E, {[(CH 3 ) 3 Si)] 3 P, [(CH 3 ) 3 Si)] 3 As, [(CH 3) 3 Si)] 3 Sb }, are used as starting materials. Straightforward, large scale syntheses of these compounds is well known to those of skill in the art. The synthesis of E(GeH 3 ) 3 is achieved by thee reaction of GeH 3 Br with [(CH 3 ) 3 Si)] 3 E according to the following equation:
3 GeH 3 Br+[(CH 3 ) 3 Si)] 3 E→3(CH 3 ) 3 Si Br+(GeH 3 ) 3 E→(where E =P,As,Sb)
GeH 3 Br is readily obtained by a single step reaction of GeH 4 with Br 2 . The (GeH 3 ) 3 E products are obtained as colorless volatile liquids and are purified by trap-to-trap fractionation.
Using this method of the present invention, we have obtained yields of the (GeH 3 ) 3 E products typically ranging from 70% to 76%. The 1 H NMR and gas phase IR data of the products are consistent with the (GeH 3 ) 3 P, (GeH 3 ) 3 As and (GeH 3 ) 3 Sb molecular structures. These data conclusively reveal that we are able to synthesize and purify the desired compounds. FIG. 1 shows a typical gas-phase FTIR spectrum of trigermylarsine, (H 3 Ge) 3 AS showing sharp absorption bands at 2077 (Ge—H stretching), 873, 829, 785 (Ge—H deformation), 530 and 487 cm −1 (Ge—H rocking). The 1 H NMR spectroscopy (not shown) consisted of a sinlet Ge—H response at 3.896 ppm. The gas-phase IR spectrum is nearly identical with that of (H 3 Ge) 3 P (which we synthesized using the same synthetic methodology) with a slight shift in absorption bands to lower wave numbers.
We have used the (GeH 3 ) 3 E compounds synthesized according to the preferred process described above as dopant sources to perform a survey of growth experiments to develop new semiconductor films on Si (100) using CVD. An alternative method for generating suitable dopant sources involves the preparation of the general family of compounds EH x (GeH 3 ) 3-x where x=1, 2 and E=P, As, Sb. These can be synthesized by reaction of inorganic or organometallic compounds of the B element with alkali germyls such as KGeH 3 or halogenated germanes such as BrGeH 3 . The products can be readily isolated and purified to give semiconductor grade reagents for in situ doping applications.
The following examples help to further explain the method described above. It will be understood, however, that the examples are illustrative of the process and materials of the invention and that the invention is not limited only to these examples.
CVD Depositions of As(GeH 3 ) 3
Depositions of pure trigermylarsine (As(GeH 3 ) 3 ) via ultra-high vacuum CVD (UHV-CVD) showed that the molecule decomposes on Si (100) at temperatures as low as 350° C. to form thin films with approximately 30 at. % As. This indicates that the entire Ge 3 As molecular core is incorporated into the deposited material. Low-pressure CVD growth of As-doped Ge 1-x Sn x films was also demonstrated. Arsenic concentrations up to 3 at. % were obtained. Doping level incorporations were also achieved by reactions of appropriate concentrations of As(GeH 3 ) 3 .
Our initial growth experiments demonstrated that compositional control of As in Ge—Sn can be obtained by simply varying the partial pressure of the reactant gases As(GeH 3 ) 3 , SnD 4 and Ge 2 H 6 . We characterized the sample films using RBS to determine the Ge to Sn ratio and using particle-induced X-ray emission (PIXE) to determine the As concentrations. FIG. 2 shows the PIXE spectrum of sample Ge—Sn:As films. Quantification obtained from fitting the peaks shows that the sample films contained about 3 at. % As. We used Secondary Ion Mass Spectrometry depth profile analysis (SIMS) to determine the As elemental distribution and Hall/FTIR ellipsometry measurements to determine carrier concentrations and effective masses. Initial deposition studies have shown that As is readily incorporated into the Ge—Sn lattice. Low energy SIMS of the samples showed highly homogeneous profiles of As and the Ge and Sn constituent elements throughout the film. FIG. 3 is a low energy SIMS profile for a Ge—Sn:As (3 at % As concentration) sample. We used TEM to show that the microstructure and epitaxial character of the sample film is of good quality. X-ray diffraction showed that the sample film had an average diamond cubic lattice.
Following our initial growth experiments, we performed additional experiments using the process of our invention to grow sample Ge 1-x Sn x films doped with As atoms to determine optimal growth conditions for yielding high quality layers with crystalline perfection and phase homogeneity required for many desirable device applications. For these experiments, we utilized UHV-CVD reaction of SnD 4 , Ge 2 H 6 and As(GeH 3 ) 3 at 350° C. Concentrations of the reactants were selected to obtain the desired composition in the alloy.
FIGS. 4-9 show results of our characterization of a resulting Ge 0.97 Sn 0.03 film doped in situ with arsenic using the As(GeH 3 ) 3 compound as the source of the As atoms. Again, we used Rutherford backscattering (RBS) to determine the bulk concentration of the resulting films and low energy SIMS to obtain the As. elemental profile. FIG. 4 shows a typical RBS spectrum of a Ge—Sn sample dope with As. The Ge and Sn concentrations were found to be 97% and 3 at. %, respectively. The As content was determined by SIMS to be 1.71×10 21 atoms/cm 3 . The channeling for both Ge and Sn is identical, indicating that the material is single phase and that the elements occupy substitutional sites in the same average diamond structure. FIG. 5 shows a low energy SIMS profile of a Sn 0.03 Ge 0.97 sample doped with As. The elemental profiles indicate that the films have a highly uniform As concentration throughout the sample. These SIMS data were used to quantify the dopant content using implanted samples of known concentration as a standard, and the As content of the Sn 0.03 Ge 0.97 sample was determined to be ˜10 21 atoms per cm 3
FIGS. 6-8 show cross sectional electron micrographs of the Ge—Sn:As sample films, which indicate single crystal quality, a high degree of epitaxial alignment and smooth surface morphology. FIG. 6 is a cross sectional view of the entire layer of a GeSn:As/Si(100) sample showing a highly uniform film thickness and smooth and continuous surface morphology. FIG. 7 is a magnified view of the GeSn:As/Si(100) heterostrucure showing that most of the defects are concentrated near the film/substrate interface while the upper portion of the layer remains relatively defect free. The inset of FIG. 7 is a selected area electron diffraction pattern which shows that the epitaxial GeSn:As layer is highly aligned on the Si substrate. FIG. 8 is a high resolution image of the interface in the (110) projection showing high quality heteroepitaxial character.
Atomic force microscopy was used to examine the surface structure and morpholoy of the Ge 0.97 Sn 0.03 :As film. FIG. 9 is an atomic force microscopy (AFM image of such a film, showing extremely smooth surface topology with a typical RMS value of 0.7 nm.
CONCLUSION
The above-described invention possesses numerous advantages as described herein. The invention in its broader aspects is not limited to the specific details, representative devices, and illustrative examples shown and described. Those skilled in the art will appreciate that numerous changes and modifications may be made to the preferred embodiments of the invention and that such changes and modifications may be made without departing from the spirit of the invention. It is therefore intended that the appended claims cover all such equivalent variations as fall within the true spirit and scope of the invention. | A process for is provided for synthesizing a compound having the formula E(GeH 3 ) 3 wherein E is selected from the group consisting of arsenic (As), antimony (Sb) and phosphorus (P). GeH 3 Br and [CH 3 ) 3 Si] 3 E are combined under conditions whereby E(GeH 3 ) 3 is obtained. The E(GeH 3 ) 3 is purified by trap-to-trap fractionation. Yields from about 70% to about 76% can be obtained. The E(GeH 3 ) 3 can be used as a gaseous precursor for doping a region of a semiconductor material comprising Ge, SnGe, SiGe and SiGeSn in a chemical vapor deposition reaction chamber. | 2 |
FIELD OF THE INVENTION
The present invention relates to a process for rapidly cooking, under an increased pressure, alimentary "pastas", such as noodles and similar filamentary "pastas", which process is capable of allowing pre-established doses of cooked "pasta" to be automatically produced, at time intervals which may even be shorter than 1 minute.
The present invention relates also to an automatically operating apparatus to practice said process.
BACKGROUND OF THE INVENTION
Several processes and relevant automatic apparatuses for rapidly cooking, under an increased pressure, doses of alimentary "pasta", in particular noodles and the like, which processes are capable of enabling doses of "pasta" cooked and ready-to-eat to be distributed at short time intervals, are already known.
In general, the processes known from the prior art to rapidly cook these alimentary "pastas" substantially envision an initial pre-cooking in water for a time of 40-50 seconds inside a vertical-axis chamber under high pressure and at a high temperature and, soon after, an end cooking also for a few seconds time, at a lower temperature, in order to enable "pasta" to absorb the correct water amount.
At the end of the cooking step, the dose of "pasta" is separated from cooking water, and is transferred to trays or dishes to be eaten
Some of these processes end apparatuses for rapidly cooking alimentary "pastas" under an increased pressure are reported, e.g., in the following issued patents/published patent applications.
Namely, published International patent application WO 87/04910 relates to the fast cooking of filamentary alimentary "pastas", which is attained by carrying out the pre-cooking step of a metered amount of "pasta" inside a chamber installed inside a kettle, at a high-temperature (i.e., at 130° C.-150° C.) and under a pressure comprised within the range of from 4 to 6 bars. Water enters the pre-cooling chamber from the bottom thereof and after a 40 seconds time "pasta" becomes soft; said softened "pasta" is then sent to an end-cooking chamber and after about 40 seconds is discharged onto a tray, ready-to-eat. The apparatus adopts various contrivances to improve the operating conditions, to recover the heat contained in the waste water, and a feeder for raw "pasta" of carrousel or dial type, with a plurality of compartments each containing a dose of "pasta" to be cooked.
U.S. Pat. Nos. 3,937,135 and 3,877,344 relate to a same fast-cooking process, and differ from each other only because according to the second patent, a centrifugal separator is used to remove the excess of cooking water, whilst tile first one uses, for that purpose, a separator of a different type. Both said patents accomplish the cooking step inside a pressurized chamber, which is separated from the heated-water kettle, and is kept at a temperature higher than 100° C.; pre-cooked "pasta" is transferred by the same water pressure to an end-cooking chamber from which excess water is removed from cooked "pasta" by means of a separator.
According to Italian patent application No. 65,711 A/83, a kettle is used which is at a temperature comprised within the range of from 120° C. to 180° C., and is equipped with a cooking chamber partially of cone-frustum shape fop the direct cooking of "pasta", with cooked "pasta" being discharged from the bottom; whereas Italian patent application No. 66,710 A/83 provides a pre-cooking chamber installed inside the interior of the kettle and a separate end-cooking chamber provided with a stirring fork to stir "pasta" during the end-cooking step; pre-cooked "pasta" is pushed into the interior of the end-cooking chamber by the same water pressure existing inside the pre-cooking chamber.
Furthermore, in Italian patent application No. 9470 A/85, the pre-cooking chamber is placed inside the kettle and the end-cooking chamber is connected with a heat exchanger to recover heat contained in cooking water.
Finally, also Italian patent No. 1,221,703 provides a pre-cooking chamber inside the interior of the kettle, and a conditioning chamber i.e., a chamber inside which the end-cooking of "pasta" takes place.
All these, as well as other apparatuses known from the prior art to rapidly cook alimentary "pastas" only partially solved the several problems one should solve in the practice in order to enable an automatic cycle for fast cooking alimentary "pastas" in particular noodles to be correctly exploited at a commercial level, simultaneously securing a rigorous constancy of the quality of the obtained product, also after a large number of operating cycles.
In fact, the total time required by such a type of cooking cycle should preferably be shorter than 1 minute; the pressurized chambers and kettles for hot water must have a capacity lower than 5 liters due to homologation reasons; the absorbed powers should be of not more than 4.5 kW in order to have energy costs compatible with the market of automatic dispensers, "pasta" should be cooked in a uniform way, and should remain uniform until it is actually dispensed; and furthermore the cooking apparatus must be reliable, i.e., it should not show drawbacks also after long operating times, and furthermore should not undergo jammings or stoppages during the step of loading of raw "pastas".
SUMMARY OF THE INVENTION
therefore, a purpose of the instant invention is of providing a process for fast cooking alimentary "pastas" under increased pressure, and a suitable apparatus for practicing said process, which are so conceived as to meet all of the requisites and requirements posed by an automatic cycle for cooking filamentary alimentary "pastas", useable as an automatic dispenser of doses of cooked "pastas", variable as desired.
Another purpose of the invention is of providing a fast cooking apparatus, which is so constructed as to result compact and reliable, requires a low energy consumption, can be used both continuously and at time intervals, and is equipped with means capable of securing a regular operation thereof, without it undergoing jammings and hence such as to require an extremely reduced servicing.
These and still further purposes, which are better evidenced in the following, are achieved by a process for fast cooking, under increased pressure, doses of filamentary alimentary "pastas" and the like, in particular noodles and the like, of the type envisaging an initial step of pre-cooking raw "pasta" under an increased pressure, with high-temperature water, a step of end cooking at a lower temperature, a step of metering of the "pasta" to be fed to the process, and means for separating cooking water from cooked "pasta", which process comprises according to the present invention, the following steps:
constantly maintaining, inside a kettle or the like, water under an increased pressure and at a high temperature, suitable for being fed to said pre-cooking chamber and possibly to said end-cooking chamber in order to stabilize the temperature thereof;
uniformly and constantly pre-heating said pre-cooking chamber by water under an increased pressure and at a high temperature, withdrawn from said kettle;
feeding a metered amount of raw "pasta", previously prepared inside an automatic metering unit, into said pre-cooking chamber together with water withdrawn from said kettle in order to lubricate said dose of raw "pasta";
perform the under-increased-pressure-pre-cooking step for a pre-established time, comprised within the range of from 15 to 20 seconds, by means of water withdrawn from said kettle, so as to obtain a soft enough "pasta";
send a further amount of pressurized water, withdrawing from said kettle, into said pre-cooking chamber, in such a way as to cause "pasta" to be stirred;
causing pre-cooked "pasta" to be transferred into said end-cooking chamber, kept thermostatted, by effect of the pressure drop existing between said chambers, combined with the thrust applied by the stirring water jet;
maintaining said pre-cooked "pasta" inside said end-cooking chamber for a time comprised within the range of from 15 to 20 seconds, at a constant, controlled temperature; and, after the end cooking
removing the steam generated by the hot cooking water causing said water to circulate through a cascade of expansion chambers in order to cause a decrease in its pressure to take place before said water reaches a heat exchanger associated with the kettle feed pipe, with also said cooking water being sent to said heat exchanger.
More particularly, during the end-cooking step, the necessary amounts of salt and/or oil are added. Furthermore, said end-cooking chamber is thermostatted by exploiting the exceeds of pressure which occurs during the step of pre-heating and thermostatting of the pre-cooking chamber.
An apparatus for fast cooking, under increased pressure, filamentary alimentary "pastas", suitable for practicing said process comprises, according to the present invention:
a kettle boiler, equipped with heating means, fed by the water distribution network through a heat exchanger, and destined to produce high-temperature pressurized water;
a vertical-axis pre-cooking chamber thermostatted by means of hot water fed from said kettle and connected, at its upper end, with a hopper fop feeding raw "pasta" through a mobile-compartment metering unit and, at its bottom, with an end-cooking chamber;
means for hydraulically connecting said kettle with the base of said pre-cooking chamber and with the top of said chamber, so as to enable water to be sent from said kettle to both opposite ends or said pre-cooking chamber;
an end-cooking chamber with an openable bottom, destined to receive the "pasta" pre-cooked in said pre-cooking chamber, and equipped with means for controlling the temperature both by respectively withdrawing hot and/or cold water from said pre-cooking chamber and from the external water-distribution system, and by controlled-expansion means to gradually reduce the pressure of steam formed inside said chamber during the transfer of said pre-cooked "pasta" into it;
a plurality of expansion chambers installed in cascade downstream said end-cooking chamber, suitable for gradually reducing the pressure of steam generated by the cooking water before feeding said water to said heat exchanger, to which also said cooking water is fed; and
a microprocessor-based data processing unit or the like, suitably programmed in order to carry out the operating steps of the units which compose the apparatus.
The structural and functional characteristics of said apparatus will be clearer from the following disclosure in detail of a preferred, made by referring to the accompanying drawing tables, supplied for merely indicative purposes, in which:
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a schematic assembly view of the apparatus according to the present invention,
FIGS. 2 and 2a show a raw-"pasta" metering/feeding unit, constructed according to the instant finding and shown in its loading position, whilst
FIGS. 3 and 3a show the same metering/feeding unit in its discharging position.
DETAILED DESCRIPTION OF THE INVENTION
Referring in particular to FIG. 1, the apparatus for fast cooking filamentary alimentary "pastas" is constituted by a kettle or boiler 1 with a capacity of less than 5 liters, to which water is fed through a pipe 2 equipped with a non-return valve 2a; water is withdrawn from a suitable source such as, e.g., the normal water distribution system 3, through a filter/water softener 4, by means of a pump 5, and flows through a heat exchanger 6, the task of which is explained in detail in the following.
The flow rate of water is controlled by a flow meter 7 and water contained inside the kettle is heated by a metal-clad electrical resistor 8 up to a temperature of about 175° C. and a pressure of 8.5 bar. The pressure inside the kettle is regulated by a pressure switch 9, and a temperature measuring device 10 measures the temperature of water; the kettle is moreover equipped with a safety valve 11 which opens when the internal pressure reaches the value of 10 bar.
With the kettle a pre-cooking chamber 12 is associated, which has a shape, e.g., cylindrical, such as to contain the full length of the filamentary-shaped "pasta"; said chamber is put into communication with the kettle through a non-return valve 13; at both ends of said chamber 12 two ball valves 14 and 15 are respectively provided, wherein the first ball valve enables "pasta" to enter the pre-cooking chamber 12 and the second ball valve enables "pasta" which ended its pre-cooking step, to be transferred to the following step.
Said chamber 12 is surrounded by a jacket 16, e.g., a metal jacket, which defines an air space 17 destined to be filled with water, through a valve 13a, which puts said air space 17 into communication with the kettle 1, which filling water is at the same temperature and pressure as of water contained inside said kettle, thus allowing a perfect uniformity of temperature to be reached during the pre-cooking step. Said air space 17 is put into communication with the following cooking chamber through a non-return valve 18, regulated by a pressure switch 19 because of reasons which are better explained in the following. A funnel 20 with suitable size enables raw "pasta" to be perfectly charged to the pre-cooking chamber 12, and a solenoid valve 21 makes it possible water to be withdrawn from the kettle 1 and to be sent to an ejector 22 hanging over the valve 14, due to reasons which also are explained in the following.
with the thermostatted chamber 12 an end-cooking chamber 23 is then associated, which is put into communication with the pre-cooking chamber 12 through said ball valve 15 and with the air space 17, through said valve 18 controlled by said pressure switch 19; the bottom 24 of said chamber 23 is in the form of a bottom plate, which is so mounted as to be capable of tilting, by effect of an arm 25 hinged in 25a; said bottom plate 24 is kept normally closed through a spring which applies an adequate force.
Furthermore, the bottom plate 24 is equipped with an upper perforated plate 26 integral with it and made with such a size as to enable the residual cooking water to be discharged at cycle end; the same bottom plate 24 is provided with a hole, and a flexible duct 27 puts said hole into communication with the pump 28; inside the container 23, and preferably in the lower portion thereof, a temperature control means 28a is installed; said temperature control means, set at a temperature comprised within the range of from 80 to 95° C., both acts on the value 29 which, through the duct 30, can withdraw cold water downstream the filter 4, and on a valve 31 which makes it possible hot water to be supplied to the container 23 withdrawing it from the kettle 1 through a duct 23a.
In the bottom portion of the container 23 a metal body 31a, of preferably conical shape, is positioned, which is provided with at least one calibrated bore 32b. Said metal body can freely slide along the cylindrical walls of said container; above the body 31a a suitably calibrated spiral spring 32 hangs over. Said cone-shaped body performs the function of regulating the escape of steam and also the very important function of preventing heat from being dispersed too rapidly from the bottom zone of the container 23, with temperature in said zone consequently undergoing undesired sharp decreases.
According to another form of practical embodiment, said controlled-expansion metal body to gradually reduce pressure can also be advantageously constituted by a metal disk having a diameter equal to the inner diameter of the container 23 and which, when is under resting conditions, realizes a substantially tight seal against the cylindrical wall of the container, and is subdivided into two equal half-circles hinged on a pivot along the diameter of the circle, so as to be able to rotate upwards around the pivot and to be lifted under the thrust generated by the pressure of steam contained inside the bottom portion of the container, counteracting the same pressure with their weight and/or with suitable return means, so as to enable amounts of steam, and of heat, to be released to the external environment in a controlled and calibrated way.
At the top of the end-cooking chamber 23, a container 33 is associated, which has a volume which is equal to 60% of volume of chamber 23. Said container 33 is put into communication with the latter by means of a pipe 34. The container 33 is connected with the chamber 23 also by a "T"-shaped pipe 35 whose diameter is half of diameter of pipe 34; said "T"-shaped pipe is connected with a discharge 36 of heat exchanger 6 through a pipe 35a preferably having the same diameter.
Downstream said container 33 there is furthermore positioned another container 37, whose volume is preferably equal to 50% of volume of container 33, connected with the latter by a pipe 38 which preferably has the same diameter as pipe 34; said container 37 is then connected with said pump 28 through a pipe 39 and with the inlet to the heat exchanger 6 through a pipe 40 whose diameter is preferably equal to the diameter of pipe 35.
The apparatus is then completed by an electronic, microprocessor-based device or the like, so programmed as to automatically accomplish, according to a preset sequence, the cooking cycle; for that purpose, all of the above listed valves are constituted by solenoid valves, and the pumps are constituted by motor-driven pumps.
In order to feed metered portions or amounts of raw "pasta" to the pre-cooking chamber 12, a mobile-wall metering device is provided, accomplished according to the present finding, of the type as depicted in figures 2-2a and 3-3a.
Said metering device is positioned above the charging funnel 20 and is constituted by a stationary inclined plate 41 (FIGS. 2 and 3), opposite to a second plate 42, also stationary and either vertical or inclined in the reverse direction, so as to generate with said plane 41 a hopper, the lower, longitudinal opening 43 of which is alternatively closed and opened by two plates 44-44a, which are at an angle to each other and are integral with a drive plate 45 which is mounted freely pivotal around an axis 46, parallel to the longitudinal slot 43. The mobile plate 45 is retained in an inclined position by a pre-loaded spring anchored to the lower portion, chute-shaped 41a of the stationary inclined plane 41. Then, to the chute-plate 41a a plate 49 is hinged in 48 and, under the latter, a tray-container 50 is positioned, hinged at an end around an axis 51 perpendicular to the axis of rotation 46 or the mobile plate 45. The container 50 is driven by a motor means of its own enslaved to said microprocessor.
Between the plates 41 and 42 raw "pasta" is deposited and in such case the inclined plate 44 keeps closed the opening or slot 43; when the container 50 is rotated upwards (FIG. 3), said rotation causes the plate 49 to be lifted relatively to the chute 41a, the spring 47 is released and therefore the mobile plate 45 is approached to the plate 42, thus opening the discharge slot 43.
The room between the two closure plates 44 and 44a (FIG. 2a) is such as to house a dose of "pasta" and when said dose has stopped between the plates 41a and 49 (FIG. 3), the tray 50 turns into horizontal by being urged to return by the spring 47; this movement brings the plate 44 to its position of closure of the slot, stopping the falling down of "pasta" and then enabling another dose thereof to be expelled, i.e., when the container will be lifted again in order to discharge the dose of "pasta" into the pre-cooking chamber.
The fast cooking cycle accomplished by the above disclosed apparatus can be summarized as follows:
The kettle 1 is brought into its steady-state operating conditions by energizing the resistor 8 (which is provided with such a value as to absorb a maximum power of 4.5 kW), until water reaches a temperature comprised within the range of from 160° to 175° C., at a pressure comprised within the range of from 7.5 to 8.5 bar, then the metering device is loaded with filamentary "pasta".
Any possible excess of pressure is vented by the valve 13 into the chamber 23. A blank cycle is then carried out to heat the whole system; the temperature-control means 28a requests water through valves 31 and/or 29 in order to keep the temperature controlled at a value of preferably 80°-95° C.
When the preliminary operations are over, the container 50 of the feeding system moves to the vertical position and applying a pressure to plate 45 and opening the spring 47 enables "pasta" to fill the room bounded by plates 41a and 49; then the container 50 moves back to its initial position, while the portion of "pasta" bounded by plates 49a and 49 falls into the container 50 and is ready to be poured into chamber 12.
At this point the pre-cooking cycle starts; the microprocessor checks whether temperature and pressure inside the kettle have the preset values for them, of, e.g., 175° C. and 8.5 bar, respectively. In the affirmative, the microprocessor opens the valve 14 and the loader 50 gets tilted. causing "pasta" to fall down into chamber 12; during such a function, a small amount of water is fed into the funnel 20 and then the valve 14, through the valve 21 and the spout 22; the basic task of said water is of preventing "pasta" (in particular, the small pieces of filamentary "pasta") from possibly sticking to the valve, thus preventing a large number of cycles from being correctly performed; to the loading device 50 getting titled the formation corresponds of another portion of "pasta" ready for the following cycle; when the charge is completed, the valve 14 is closed and cooking water is fed, preferably from the bottom upwards, into the chamber 12 through the valve 13; only after that said water has been fed to the chamber 12 a further amount of water is recalled through the pump 5 to replace inside the kettle the amount of water transferred into the pre-cooking chamber; during the several steps of the cycle, the microprocessor controls the temperature of water inside the air space 17.
When "pasta" has been softened (after approximately 15 seconds) and then has come to lay on the bottom of the chamber 12, a further amount of water is fed through the valve 13; this second feed stirs "pasta", favouring a uniform cooking (this operation can be repeated more times). After approximately 30 seconds, the valve 15 is opened and "pasta", is pushed, mixed with cooking water, into the chamber 23, owing to the difference in pressure; inside said chamber 23, the cooking of "pasta" ends within a time of from 15 to 30 seconds, according to whether a more of less complete type of cooking is selected, absorbing necessary water; the steam generated during the opening goes into the container 33 through the connection 34 and then into the container 37 through the connection 38, finally reaching the inlet end of the heat exchanger 6; such a system decreases pressure and temperature of concerned fluids, thus enabling the efficiency of the cycle to be increased. A portion of said steam returns back into the chamber 23 through the duct 35; a small amount of condensate is disposed off through the pipe 35a and is sent to the outlet end 36 of the heat exchanger 6; when "pasta" is transferred from chamber 12 to chamber 23, the steam generated lifts the cone 31a, causing it to apply a pressure against spring 32; the latter lowers again the cone 31a, whilst steam outflows through the bore 32b of said cone, thus keeping temperature more uniform.
During the end cooking step, salt dissolved in water and possibly oil drops are added to prevent "pasta" from forming clumps.
When cooking is ended, "pasta" is separated from water through the pump 28 which causes water to be discharged through the perforated wall 26; water is sent to the body 37 and then to the heat exchanger 6, thus realizing a high degree of heat recovery; starting from the first cycle ahead, in fact, the temperature of heat exchanger increases and kettle 1 is thus red with pre-heated water.
Finally, the bottom plate 24 is tilted and the dose of cooked "pasta" is deposited inside a container 24a. When "pasta" is expelled from pre-cooking chamber 12, the latter is ready to receive a new load of "pasta" in order to optimize the operating times of the machine when said machine operates under continuous operating conditions. Inasmuch as when the machine operates continuously, the temperature of container 23 tends of course to increase, this drawback is obviated by controlling said temperature by means of the temperature control unit 28a; in such a way, cooking degrees ape obtained, which ape absolutely constant and repeatable even for a large number of portions. Furthermore, at regular time intervals, e.g., every six minutes, the machine performs an idle cycle (i.e., without "pasta") to perform a complete washing of the system.
When the machine operates batchwise, at regular time intervals, preferably shorter than as in previous case (e.g., every two minutes), the machine performs a cycle with a small water amount, e.g., 50 g, to keep the system at the desired temperature. As said, the reverse cone 31a also performs the task of preventing a too fast heat dispersion, with a consequent undesired drop in temperature of the lower portion of container 23.
Possible overpressures inside the air space 17 are eliminated through the valve 18 controlled by the pressure switch 19 which in such case sends water to the end cooking chamber 23 in order to maintain it at the correct temperature value.
From the above, the matter of fact clearly appears that the particular structure of the apparatus, and, in particular, the temperature control of the pre-cooking chamber and the presence of the pressure containers 23, 33 and 37, make it possible, as a whole, an amount of power to be consumed which is not higher than 4.5 kW to heat the water contained inside the kettle, simultaneously making it possible a very fast complete cooking cycle at maximum of one minute pep each portion to be carried out.
Obviously, when the present invention, as disclosed and illustrated as above, is practically carried out, structurally and functionally equivalent modifications and variants can be supplied to it without departing from the scope of protection of the same finding. | Process for fast cooking filamentary alimentary pastas and the like, consisting in feeding high-temperature, pressurized water to a pre-cooking chamber thermostatted by means of the same high-temperature water, feeding to the chamber, and by means of a metering feeder, a portion of raw pasta together with hot water, and keeping the pasta under such condition until the pasta is softened, feeding a further amount of hot water to the pre-cooking chamber in order to stir the softened pasta, transferring the pasta to a thermostatted end-cooking chamber, and removing hot cooking water causing the hot water to circulate through a plurality of expansion chambers before being sent to a heat exchanger associated with the water feed pipe. Fast-cooking apparatus suitable for practicing the process in an automatic way, in which the operating cycle is governed by a microprocessor, or the like. | 0 |
REFERENCE TO PENDING PRIOR PATENT APPLICATIONS
This is a continuation of prior U.S. patent application Ser. No. 09/714,549, filed Nov. 16, 2000 now U.S. Pat. No. 6,733,506 by Dennis McDevitt et al. for APPARATUS AND METHOD FOR ATTACHING SOFT TISSUE TO BONE. The above-identified patent application is hereby incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates generally to medical devices and procedures. More particularly, this invention relates to apparatus and methods for attaching soft tissue to bone.
BACKGROUND OF THE INVENTION
The complete or partial detachment of ligaments, tendons and/or other soft tissues from their associated bones within the body are relatively commonplace injuries, particularly among athletes. Such injuries are generally the result of excessive stresses being placed on these tissues. By way of example, tissue detachment may occur as the result of an accident such as a fall, over-exertion during a work-related activity, during the course of an athletic event, or in any one of many other situations and/or activities.
In the case of a partial detachment, the injury will frequently heal itself, if given sufficient time and if care is taken not to expose the injury to further undue stress.
In the case of complete detachment, however, surgery may be needed to re-attach the soft tissue to its associated bone or bones.
Numerous devices are currently available to re-attach soft tissue to bone. Examples of such currently-available devices include screws, staples, suture anchors and tacks.
In soft tissue re-attachment procedures utilizing screws, the detached soft tissue is typically moved back into its original position over the bone. Then the screw is screwed through the soft tissue and into the bone, with the shank and head of the screw holding the soft tissue to the bone.
Similarly, in soft tissue re-attachment procedures utilizing staples, the detached soft tissue is typically moved back into its original position over the bone. Then the staple is driven through the soft tissue and into the bone, with the legs and bridge of the staple holding the soft tissue to the bone.
In soft tissue re-attachment procedures utilizing suture anchors, an anchor-receiving hole is generally first drilled in the bone at the desired point of tissue re-attachment. Then a suture anchor is deployed in the hole using an appropriate installation tool. This effectively locks the suture to the bone, with the free end(s) of the suture extending out of the bone. Next, the soft tissue is moved into position over the hole containing the deployed suture anchor. As this is done, the free end(s) of the suture is (are) passed through or around the soft tissue, so that the free end(s) of the suture reside(s) on the far (i.e., non-bone) side of the soft tissue. Finally, the suture is used to tie the soft tissue securely to the bone.
Alternatively, in some soft tissue re-attachment procedures utilizing suture anchors of the type described above, the soft tissue may first be moved into position over the bone. Then, while the soft tissue lies in position against the bone, a single hole may be drilled through the soft tissue and into the bone. Next, a suture anchor is passed through the soft tissue and deployed in the bone using an appropriate installation tool. This results in the suture anchor being locked to the bone, with the free end(s) of the suture extending out of the bone and through the soft tissue. Finally, the suture is used to tie the soft tissue securely to the bone.
In some cases, the suture anchor may include drill means at its distal end, whereby the suture anchor can be drilled into the bone, or drilled through the soft tissue and into the bone, whereby the aforementioned drilling and anchor-deployment steps are effectively combined.
Similarly, in soft tissue re-attachment procedures utilizing tacks, the detached soft tissue is typically moved back into its original position over the bone, and then a tack-receiving hole is generally drilled through the soft tissue and into the bone. Then the tack is driven through the soft tissue and into the bone, so that the shaft and head of the tack will hold the soft tissue to the bone.
While systems and method based on the aforementioned screws, staples, suture anchors and tacks are generally effective, they also all suffer from one or more disadvantages.
OBJECTS OF THE INVENTION
Accordingly, one object of the present invention is to provide a novel apparatus and method for re-attaching soft tissue to bone which improves upon the prior art devices and techniques discussed above.
Another object of the present invention is to provide a novel apparatus and method for re-attaching soft tissue to bone which is easy to use and simple to perform.
And another object of the present invention is to provide a novel apparatus and method for re-attaching soft tissue to bone which expedites and facilitates the re-attachment procedure.
Still another object of the present invention is to provide a novel apparatus and method for re-attaching soft tissue to bone which minimizes trauma to the patient during the re-attachment procedure.
Yet another object of the present invention is to provide a novel apparatus and method for re-attaching soft tissue to bone which can be used in both open surgical procedures and in closed surgical procedures (e.g., arthroscopic or endoscopic surgical procedures) where access to the surgical site is provided by one or more cannulas.
And another object of the present invention is to provide a novel system and method for re-attaching soft tissue to bone which is also usable in the attachment of prosthetic devices, and/or grafts of natural and/or synthetic material, to bone or bone-like structures.
SUMMARY OF THE INVENTION
These and other objects of the present invention are achieved by the provision and use of a novel apparatus and method for attaching soft tissue and the like to bone.
In one preferred embodiment, the novel apparatus comprises an expandable body configured to expand into bone, the expandable body defining a bore; and an expander pin comprising a shaft sized to be received in the bore of the expandable body and expand the expandable body laterally when the expander pin is driven into the expandable body, and tissue attachment apparatus associated with the shaft, the expander pin defining a bore; whereby when the expander pin is driven into the expandable body, the expandable body will be attached to bone and the tissue attachment apparatus will secure tissue to the apparatus.
In one preferred embodiment, the novel method comprises driving an expandable fastener into a bone, the expandable fastener defining a bore and comprising tissue attachment apparatus; and fixing the expandable fastener in, and thereby securing the tissue relative to, the bone.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and features of the present invention will be more fully disclosed or rendered obvious by the following detailed description of the preferred embodiments of the invention, which is to be considered together with the accompanying drawings wherein like numbers refer to like parts, and further wherein:
FIG. 1 is a side view of a novel fastening apparatus formed in accordance with the present invention;
FIGS. 2-4 are perspective views of the distal end of the fastening apparatus shown in FIG. 1 ;
FIG. 5 is a side view, partially in section, of the distal end of the fastening apparatus shown in FIG. 1 ;
FIG. 6 is an exploded view showing the fastener, and a portion of the installation tool, of the fastening apparatus shown in FIG. 1 ;
FIGS. 7 and 8 are perspective, exploded views of the elements shown in FIG. 5 ;
FIGS. 9-11 show details of the distal tip member of the fastener shown in FIG. 5 ;
FIGS. 12 and 13 show details of the proximal main member of the fastener shown in FIG. 5 ;
FIGS. 14-16 show details of the expander pin of the fastener shown in FIG. 5 ;
FIGS. 17-19 show details of the pusher member of the installation tool shown in FIG. 5 ;
FIG. 20 is an exploded side view of the handle assembly of the installation tool shown in FIG. 1 ;
FIGS. 21-25 show the novel fastening apparatus of the present invention being used to attach soft tissue (or the like) to bone;
FIGS. 26-28 illustrate one preferred form of the novel fastening apparatus of the present invention being used to attach soft tissue (or the like) to bone;
FIGS. 29 and 30 illustrate another preferred form of the novel fastening apparatus of the present invention being used to attach soft tissue (or the like) to bone;
FIG. 31 is a side view showing an alternative form of proximal main member for a fastener formed in accordance with the present invention;
FIG. 32 is a side view showing an alternative form of distal tip member for a fastener formed in accordance with the present invention;
FIGS. 33-35 show details of an alternative form of the fastener's expander pin;
FIGS. 36-38 show details of another alternative form of the fastener's expander pin;
FIGS. 39-42 show details of the construction of an alternative form of fastener also formed in accordance with the present invention;
FIGS. 43 and 44 show the fastener of FIGS. 39-42 being used to attach soft tissue (or the like) to bone;
FIG. 45 shows details of an alternative form of expander pin for the fastener shown in FIGS. 39-44 ;
FIGS. 46-49 show details of the construction of another alternative form of fastener also formed in accordance with the present invention;
FIGS. 50-53 show the fastener of FIGS. 46-49 being used to attach soft tissue (or the like) to bone;
FIG. 54 shows details of an alternative form of expander pin for the fastener shown in FIGS. 46-53 ;
FIGS. 55 and 56 show details of a removal tool for removing a fastener formed and deployed in accordance with the present invention;
FIG. 57 illustrates an alternative embodiment of expandable body;
FIG. 58 illustrates an alternative embodiment of the expander pin; and
FIG. 59 illustrates another alternative embodiment of the expander pin.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Looking first at FIG. 1 , there is shown a fastening apparatus 5 for attaching soft tissue (or the like) to bone. Fastening apparatus 5 generally comprises a fastener 10 and an installation tool 15 .
Looking next at FIGS. 1-8 , fastener 10 generally comprises an expandable body 100 ( FIG. 2 ) and an expander pin 200 .
Expandable body 100 comprises a generally frusto-conical distal end 105 ( FIG. 5 ) characterized by a frusto-conical outer surface 110 terminating in a distal end surface (or rim) 115 , and a generally cylindrical proximal end 120 terminating in a proximal end surface 125 . A central passageway 130 extends through expandable body 100 , from distal end surface 115 to proximal end surface 125 .
In a preferred form of the invention, central passageway 130 comprises a bore 135 opening on distal end surface 115 , a threaded section 140 , and a bore 145 opening on proximal end surface 125 .
Expandable body 100 preferably also comprises bone securement apparatus 150 formed on proximal end 120 for facilitating securement of fastener 10 to bone, as will hereinafter be discussed in further detail. In one preferred form of the invention, bone securement apparatus 150 comprises a plurality of frusto-conical ribs 155 . Ribs 155 are tapered, distally-to-proximally, so as to (1) facilitate insertion of expandable body 100 into bone in a distal direction, and (2) resist withdrawal of expandable body 100 from bone in a proximal direction.
If desired, expandable body 100 can be formed out of a single piece of material. Preferably, however, and looking now at FIGS. 1-13 , expandable body 100 comprises a distal tip member 160 ( FIG. 9 ) and a proximal main member 165 ( FIG. 12 ).
Distal tip member 160 ( FIGS. 9-11 ) preferably comprises the aforementioned frusto-conical outer surface 110 , distal end surface (or rim) 115 , internal bore 135 , and threaded section 140 . Distal tip member 160 also preferably comprises a proximally-extending, threaded projection 170 . Proximally-extending threaded projection 170 serves to secure distal tip member 160 to proximal main member 165 , as will hereinafter be discussed in further detail.
Proximal main member 165 ( FIGS. 12 and 13 ) preferably comprises the aforementioned proximal end surface 125 , bore 145 and bone securement apparatus 150 (preferably in the form of frusto-conical ribs 155 ). Proximal main member 165 also comprises a threaded counterbore 175 at its distal end. Threaded counterbore 175 is sized and shaped so as to matingly receive proximally-extending threaded projection 170 of distal tip member 160 , whereby the two elements may be secured to one another so as to form the complete expandable body 100 .
Referring to FIG. 57 , it will be seen that in an alternative embodiment proximally-extending threaded projection 170 of the distal tip member 160 is of an annular configuration and is provided with internal threads 172 . Proximal main member 165 includes a projection 176 having external threads 178 thereon for engagement with the distal tip member internal threads 172 . Threaded projection 170 is sized and shaped so as to matingly receive threaded projection 176 of main member 165 , whereby the two elements 160 , 165 may be secured to one another so as to form the complete expandable body 100 .
A primary advantage of forming expandable body 100 out of two separate components (i.e., distal tip member 160 and proximal main member 165 ) is that each component can be optimized for its own function. More particularly, inasmuch as distal tip member 160 is intended to help open a passageway in bone to receive the overall fastener 10 , distal tip member 160 is preferably formed out of a relatively hard material. At the same time, however, inasmuch as proximal main member 165 is intended to expand radially outwardly during deployment of the fastener so as to fix expandable body 100 (and hence the complete fastener 10 ) to bone, proximal main member 165 is preferably formed out of a relatively soft and easily expandable material.
Fastener 10 also comprises the expander pin 200 . Looking next at FIGS. 1-8 and 14 - 16 , expander pin 200 generally comprises a shaft 205 and tissue attachment apparatus 210 associated with shaft 205 . Shaft 205 is sized so that it will not normally fit within central passageway 130 ( FIG. 5 ) of expandable body 100 . However, shaft 205 is also sized so that when expander pin 200 is driven longitudinally into expandable body 100 , the expander pin will force the side walls of expandable body 100 to expand radially outwardly against adjacent bone, whereby the expandable body (and hence the entire fastener) will be secured to a host bone, as will hereinafter be discussed in further detail.
Preferably, shaft 205 includes fastener stabilization apparatus 215 for stabilizing the longitudinal position of expander pin 200 relative to expandable body 100 , as will hereinafter be discussed in further detail. More particularly, fastener stabilization apparatus 215 is adapted to resist withdrawal of expander pin 200 from expandable body 100 once expander pin 200 has been driven into expandable body 100 , as will hereinafter be discussed in further detail. In one preferred form of the invention, fastener stabilization apparatus 215 comprises a screw thread 220 formed on the outer surface of shaft 205 .
Still looking now at FIGS. 1-8 and 14 - 16 , in one preferred form of the invention, tissue attachment apparatus 210 comprises one or more lateral projections 225 adjacent to the proximal end of the shaft. The one or more lateral projections 225 collectively form a fastener head for holding tissue to bone, as will hereinafter be discussed in further detail. Lateral projections 225 may be formed with a substantially convex configuration, as shown in FIG. 14 ; or lateral projections 225 may be formed with a substantially planar configuration, as shown in FIG. 58 ; or lateral projections 225 may be formed with a substantially concave configuration as shown in FIG. 59 . Furthermore, if desired, one or more distally-projecting longitudinal projections 226 ( FIG. 14 ) may be formed on the distal side of lateral projections 225 for enhancing the engagement of lateral projections 225 with underlying tissue.
Expander pin 200 includes a longitudinal passageway 230 extending the length of the expander pin.
Fastener 10 is intended to be used in conjunction with installation tool 15 . Looking next at FIGS. 1-8 , installation tool 15 comprises a shaft 300 ( FIG. 6 ) terminating in a tapered distal point 310 . Tapered distal point 310 is preferably formed so as to be relatively hard, whereby it can open a passageway in bone to receive the overall fastener 10 , as will hereinafter be discussed in further detail. Threads 315 are formed on shaft 300 proximal to tapered distal point 310 . Shaft 300 is sized so that it may be received in the central passageway 130 ( FIG. 5 ) of expandable body 100 , and in longitudinal passageway 230 ( FIG. 16 ) of expander pin 200 . Threads 315 of shaft 300 are sized and positioned so that when fastener 10 (i.e., expandable body 100 and expander pin 200 ) is mounted on shaft 300 , shaft threads 315 can mate with the expandable body's threads 140 , whereby expandable body 100 can be secured to the distal end of shaft 300 . In one preferred form of the invention, the shaft's tapered distal point 310 and the expandable body's frusto-conical outer surface 110 ( FIG. 9 ) are coordinated with one another so that when expandable body 100 is screwed onto shaft 300 , the expandable body's frusto-conical outer surface 110 will form, in a rough sense, a continuation, or extension, of the taper of the shaft's tapered distal point 310 ( FIG. 5 ).
Preferably, the installation tool's shaft 300 comprises a thinner distal section 320 ( FIG. 5 ) proximal to the shaft's tapered distal point 310 and distal to the shaft's threads 315 , and a trailing section 325 proximal to shaft threads 315 , and a thicker proximal section 330 proximal to trailing section 325 . Trailing section 325 and thicker proximal section 330 together define an annular shoulder 335 at their intersection. A rib 340 is preferably formed on trailing section 325 , distal to annular shoulder 335 .
A pusher 400 ( FIGS. 5 and 17 ) is preferably mounted on shaft 300 . Pusher 400 is used to help deploy fastener 10 in bone, by transferring a force applied to the proximal end of pusher 400 onto a fastener 10 located at the distal end of pusher 400 . In the process, pusher 400 acts as a sort of safeguard to prevent the proximal end of fastener 10 (i.e., the proximal end of expander pin 200 ) from being damaged during the application of such force. Pusher 400 preferably comprises a tapered distal portion 405 characterized by a tapered outer surface 410 terminating in a distal end surface 415 , and a cylindrical proximal portion 420 characterized by a cylindrical outer surface 425 terminating in a proximal end surface 427 . Pusher 400 has a central bore 430 extending therethrough. Bore 430 is sized so that it will form a close sliding fit with rib 340 ( FIG. 6 ) of shaft 300 . A lip 435 ( FIG. 17 ) protrudes into central bore 430 adjacent to the pusher's proximal end surface 427 . Lip 435 is sized so that it may not pass by rib 340 of shaft 300 .
In one preferred form of the invention, shaft 300 includes a plurality of ribs 345 ( FIG. 6 ) on the shaft's thicker proximal section 330 , and installation tool 15 includes a handle assembly 500 ( FIG. 20 ). Each rib 345 includes an inclined surface 345 A disposed on the proximal side of the rib ( FIG. 6 ). The distal side of each rib 345 extends substantially perpendicular to the longitudinal axis of shaft 300 .
Handle assembly 500 comprises a body 501 having a handle grip 502 . A trigger 505 , having a plurality of fingers 507 , is pivotally connected to body 501 . Body 501 also comprises a bore 508 opening on the body's distal end, and a counterbore 509 opening on the body's proximal end. A shoulder 509 A is formed at the intersection of bore 508 and counterbore 509 .
Handle assembly 500 also comprises a hollow ram 515 . Ram 515 is sized so that it can slidably accommodate shaft 300 , as will hereinafter be discussed in further detail. Ram 515 comprises a narrower distal portion 520 terminating in a distal tip 510 , and a wider proximal portion 525 including a plurality of teeth 530 . A shoulder 535 is formed at the intersection of narrower distal portion 520 and wider proximal portion 525 . A slot 540 extends through the side wall of narrower distal portion 520 .
Ram 515 is mounted in body 510 in the manner shown in FIGS. 1 and 20 , i.e., so that (1) the ram's narrower distal portion 520 extends through, and protrudes from, the body's bore 508 , (2) the ram's wider proximal portion 525 is disposed in the body's counterbore 509 , and (3) the trigger's fingers 507 engage the ram's teeth 530 . As a result of this construction, moving trigger 505 will cause ram 515 to move relative to body 501 . A spring 545 is positioned in body 501 , between body shoulder 509 A and ram shoulder 535 , so as to bias ram 515 in a proximal direction. A stop pin 550 extends into counterbore 509 so as to limit proximal movement of ram 515 .
Handle assembly 500 also comprises a gate 555 which includes an opening 560 therein. Opening 560 defines a bottom wall 565 thereof. Gate 555 is disposed in an opening 570 formed in body 501 . A spring 575 biases gate 555 against a locking pin 580 , which extends through an oversized hole 585 formed in gate 555 . Gate 555 is disposed in body 501 so that the gate's bottom wall 565 normally protrudes, via ram slot 540 , into the interior of ram 515 ; however, pressing gate 555 downward against the power of spring 575 will permit the gate's bottom wall 565 to be removed from the interior of ram 515 .
In use, and as will hereinafter be discussed in further detail, handle assembly 500 is loaded over the proximal end of shaft 300 , and moved proximally down the shaft until the gate's bottom wall 565 starts to engage the ribs 345 of shaft 300 . As this occurs, the inclined proximal surfaces 345 A of ribs 345 will allow the handle assembly 500 to be moved distally along shaft 300 to the extent desired. However, since inclined surfaces 345 A are provided on only the proximal sides of ribs 345 , the geometry of the ribs will prevent handle assembly 500 from moving back proximally along the shaft, unless gate 555 is pressed downward against the power of spring 575 so as to move the gate's bottom wall 565 out of engagement with the shaft's ribs. Handle assembly 500 is moved down shaft 300 until the ram's distal end surface 510 engages, or substantially engages, the proximal end 427 of pusher 400 . Thereafter, pulling of the handle assembly's trigger 505 will cause ram 515 to move distally along shaft 300 , whereby pusher 400 can drive expander pin 200 into expandable body 100 so as to set the expandable body in bone, as will hereinafter be discussed in further detail.
The use of handle assembly 500 in conjunction with shaft 300 is often preferred, since it permits shaft 300 to be held in place while ram 515 is advanced down shaft 300 . More particularly, inasmuch as handle assembly 500 is releasably secured to shaft 300 via the engagement of handle gate 555 with shaft ribs 345 , handle assembly 500 can stabilize shaft 300 even as the handle's ram 515 is advancing down shaft 300 . This has been found to be advantageous in many circumstances. However, it should also be appreciated that fastener 10 can be set without using handle assembly 500 , as will hereinafter also be discussed in further detail.
Looking next at FIGS. 21-25 , there is shown a general method for attaching soft tissue (or the like) to bone using the fastener of the present invention. In particular, the invention will be discussed in the context of (1) a fastener 10 comprising an expandable body 100 and an expander pin 200 ; (2) an installation tool 15 comprising a shaft 300 ; and (3) a pusher 400 mounted on shaft 300 .
The foregoing fastening system is prepared for use by first passing pusher 400 proximally over the distal end of shaft 300 until the pusher's proximal end surface 427 ( FIG. 17 ) engages, or approximately engages, the shaft's annular shoulder 335 ( FIG. 6 ). Then the fastener's expander pin 200 is passed proximally over the distal end of shaft 300 until the proximal end of expander pin 200 engages, or approximately engages, the pusher's distal end surface 415 ( FIG. 17 ). Next, the fastener's expandable body 100 is passed proximally over the distal end of shaft 300 until the proximal end of the expandable body's threaded section 140 ( FIG. 5 ) engages the distal end of the shaft's threads 315 ( FIG. 6 ). Then the fastener's expandable body 100 is screwed onto shaft 300 . At this point, the proximal end surface 125 ( FIG. 12 ) of expandable body 100 will engage, or approximately engage, the distal end surface of expander pin 200 . It will be appreciated that at this point, the expandable body 100 , expander pin 200 and pusher 400 will be held relatively immobile on shaft 300 , by virtue of shaft shoulder 335 ( FIG. 6 ) and shaft threads 315 and the sizing of the elements held therebetween.
Next, soft tissue (or the like) 600 is “stabbed” with the sharp distal point of shaft 300 and dragged to its desired position against bone 700 ( FIG. 21 ). Alternatively, soft tissue 600 may be gripped by another instrument (e.g., forceps or the like) and moved into position against bone 700 .
Then, with soft tissue 600 in position against bone 700 , shaft 300 is forced distally through tissue 600 ( FIG. 22 ) and into bone 700 ( FIG. 23 ). It will be appreciated that, as this occurs, expandable body 100 will be carried into the bone, due to the screw engagement established between expandable body 100 and shaft 300 . In fact, the tapered distal ends of shaft 300 and expandable body 100 will cooperate with one another so as to force an opening in the soft tissue and the bone, without any need for pre-drilling. Shaft 300 is preferably driven into bone 700 until the proximal end surface 125 of expandable body 100 is approximately even with the outer surface of bone 700 ( FIG. 23 ). If desired, markings (not shown) may be placed on the outer surface of the fastener's expander pin 200 so that, once the thickness of soft tissue 600 is known, proper depth penetration can be achieved.
Next, the proximal end of pusher 400 is engaged with another element (not shown in FIGS. 21-25 , but shown in subsequent figures) so as to move the pusher distally along shaft 300 . Pusher 400 is moved distally so as to drive expander pin 200 distally, into the central passageway 130 ( FIG. 5 ) of expandable body 100 , whereby to drive the side walls of expandable body 100 radially outwardly into bone 700 and thereby secure fastener 10 to bone 700 ( FIG. 24 ). At the same time, the fastener's tissue attachment apparatus 210 will secure soft tissue 600 to the bone. More particularly, as seen in FIG. 24 , the head of expander pin 200 (made up of one or more lateral projections 225 ) will bear distally against soft tissue 600 , whereby to keep the soft tissue fixed against bone 700 .
Finally, shaft 300 is unscrewed from the expandable body's threads 140 ( FIG. 5 ) and removed ( FIG. 25 ), leaving fastener 10 securing soft tissue 600 to bone 700 .
In the embodiment shown in FIG. 57 , widthwise expansion of the proximal main member 165 serves to urge the external threads 178 of the projection 176 into firm engagement with the internal threads 172 of the distal tip member 160 . Thus, the distal tip member 160 is securely held in place by the expanded proximal main member 165 to permit the shaft 300 to be unscrewed from the expandable body threads 140 and removed.
As noted above, in one preferred form of the invention, installation tool 15 is constructed so that shaft 300 includes ribs 345 ( FIG. 6 ) adjacent its proximal end, and the installation tool includes handle assembly 500 ( FIG. 20 ). FIGS. 26-28 illustrate how soft tissue 600 may be attached to bone 700 using such an arrangement. More particularly, after pusher 400 , expander pin 200 and expandable body 100 have been attached to shaft 300 in the manner described above with respect to FIGS. 21-25 , and either before or after shaft 300 is driven through soft tissue 600 and into bone 700 to the point shown in FIGS. 23 and 26 , handle assembly 500 is passed distally over the proximal end of shaft 300 until the gate 555 engages ribs 345 of shaft 300 . Handle assembly 500 is then pushed further down shaft 300 until the distal tip 510 of ram 515 engages the proximal end of pusher 400 . Then trigger 505 is activated so as to move ram 515 distally relative to pusher 400 and fastener 10 , whereby the distal tip 510 ( FIG. 20 ) of the handle assembly's ram 515 will drive distally against the proximal end of pusher 400 . This will cause pusher 400 to move expander pin 200 distally, whereby to fix fastener 10 in bone 700 , with the fastener's head fixing soft tissue 600 to bone 700 ( FIG. 27 ). Then handle assembly 500 is removed proximally off shaft 300 , i.e., by first pressing gate 555 downward against the power of spring 575 so as to move the gate's bottom wall 565 out of engagement with ribs 345 , and then pulling the handle assembly 500 proximally off the shaft. Then shaft 300 is unscrewed from the expandable body's threads 140 and removed from the surgical site ( FIG. 28 ).
It will be appreciated that, by virtue of the relative sizing of shaft rib 340 ( FIG. 6 ) and pusher lip 435 ( FIG. 17 ), pusher 400 will be slidably retained on the distal end of shaft 300 even after shaft 300 has been unscrewed from fastener 10 , since pusher lip 435 will be unable to move past shaft rib 340 .
As noted above, the use of handle assembly 500 in conjunction with shaft 300 is frequently preferred, since it permits shaft 300 to be held in place while ram 515 is advanced down shaft 300 . More particularly, inasmuch as handle assembly 500 is releasably secured to shaft 300 via the engagement of handle gate 555 with shaft ribs 345 , handle assembly 500 can stabilize shaft 300 even as the handle's ram 515 is advancing down shaft 300 . In other words, since the fastener's expandable body 100 is connected to shaft 300 by the expandable body's threaded section 140 and shaft threads 315 , and inasmuch as handle assembly 500 is releasably secured to shaft 300 via the engagement of handle gate 555 with shaft ribs 345 , the handle assembly can advance its ram 515 against the fastener's expander pin 200 even while the handle assembly is holding the shaft 300 , and hence the fastener's expandable body 100 , in place. In effect, the use of handle assembly 500 in conjunction with shaft 300 permits a proximally-directed counterforce to be applied to expandable body 100 even as a distally-directed setting force is being applied to expander pin 200 .
However, it should also be appreciated that fastener 10 can be set without using handle assembly 500 , as will hereinafter be discussed in further detail.
Thus, in another preferred form of the invention, installation tool 15 may be constructed so that shaft 300 omits ribs 345 on its proximal end, and so that the installation tool 15 does not include handle assembly 500 . In this case, pusher 400 may be moved proximally on shaft 300 by other means.
For example, and looking now at FIGS. 29 and 30 , a cannulated driver 800 , such as one having a so-called “slap hammer” configuration, can be used to drive pusher 400 distally on shaft 300 , whereby to complete setting of fastener 10 in bone 700 .
While the “slap hammer” construction shown in FIGS. 29 and 30 is simple and effective, it does suffer from the disadvantage that a proximally-directed counterforce is not being applied to expandable body 200 even as the distally-directed setting force is being applied to expander pin 300 , as is the case with the use of handle assembly 500 described above.
It should be appreciated that, if desired, the expandable body's bone securement apparatus 150 ( FIG. 12 ) may be omitted or, alternatively, replaced by a configuration different than the ribs 155 ( FIG. 12 ) previously disclosed. By way of example but not limitation, bone securement apparatus 150 may comprise screw threads 155 A shown in FIG. 31 .
It should also be appreciated that, if desired, the expandable body's distal end 105 ( FIG. 5 ) may have a configuration other than the smooth, frusto-conical one disclosed above. By way of example but not limitation, expandable body 100 may have screw threads formed on its tapered distal end. See, for example, FIG. 32 , which shows the screw threads 110 A formed on distal tip member 160 .
FIGS. 33-35 show an alternative form of expander pin 200 . More particularly, the expander pin 200 shown in FIGS. 33-35 is similar to the expander pin 200 shown in FIGS. 14-16 , except that with the expander pin of FIGS. 33-35 , lateral projections 225 A have their outlying edges 226 rounded into an arc-like configuration.
FIGS. 36-38 show yet another alternative form of expander pin 200 . More particularly, the expander pin 200 shown in FIGS. 36-38 is similar to the expander pin 200 shown in FIGS. 14-16 , except that with the expander pin of FIGS. 36-38 , fastener stabilization apparatus 215 comprises a plurality of frusto-conical ribs 220 A, rather than the screw thread 220 shown in FIGS. 14-16 .
It is also possible to form the fastener's tissue attachment apparatus 210 with a different configuration (and with a different manner of operation) than the tissue attachment apparatus shown in FIGS. 14-16 or 33 - 36 .
More particularly, with the tissue attachment apparatus 210 shown in FIGS. 14-16 and 33 - 36 , the tissue attachment apparatus essentially comprises a head for capturing the soft tissue to bone. However, it is also contemplated that tissue attachment apparatus 210 may comprise a suture-based mechanism for capturing the soft tissue to bone.
More particularly, and looking now at FIGS. 39-42 , there is shown a fastener 10 in which tissue attachment apparatus 210 comprises a plurality of transverse bores 227 formed in expander pin 200 adjacent to its proximal end. Bores 227 accommodate one or more lengths of suture 228 ( FIG. 39 ) which may be used to tie a piece of soft tissue (or the like) to bone. In one preferred form of the invention, expander pin 200 includes a cylindrical proximal end portion 229 ( FIG. 40 ) having a diameter larger than the diameter of the central passageway 130 ( FIG. 5 ) of expandable body 100 , with transverse bores 227 being formed in cylindrical proximal end portion 229 .
In use, the fastener is set through soft tissue 600 and into bone 700 in the normal manner ( FIGS. 43 and 44 ); however, since the fastener lacks the lateral projections 225 ( FIG. 14 ) previously disclosed, the proximal end of expander pin 200 will pass through soft tissue 600 without binding it to the bone ( FIG. 44 ). However, sutures 228 will extend out of bone 700 and through soft tissue 600 . As a result, these sutures may then be used to tie the soft tissue down to the bone.
If desired, the expander pin 200 shown in FIGS. 39-44 can be modified so as to have its fastener stabilization apparatus 215 in the form of ribs 220 A ( FIG. 45 ), rather than the screw thread 220 shown in FIG. 40 .
With respect to the fastener configuration shown in FIGS. 39-45 , it should be appreciated that by positioning transverse bores 227 ( FIG. 40 ) in the diametrically-enlarged proximal end portion 229 , the transverse bores 227 will remain proximal to expandable body 100 even after setting of the fastener ( FIG. 44 ). As a result of this construction, sutures 228 will be able to slip within bores 227 even after fastener 10 has been completely deployed in bone 700 . As will be apparent to persons skilled in the art, this can be advantageous in some circumstances during tissue fixation.
It is also possible to fabricate a fastener 10 with a suture-based mechanism for capturing soft tissue to bone, but where the sutures are prevented from slipping relative to the fastener once the fastener has been fully deployed in the bone.
More particularly, and looking now at FIGS. 46-49 , there is shown a fastener 10 which includes an expander pin 200 having a plurality of transverse bores 227 intermediate its length ( FIG. 47 ). Bores 227 accommodate the one or more lengths of suture 228 which may be used to tie a piece of soft tissue (or the like) to bone. In one preferred form of the invention, expander pin 200 includes a cylindrical intermediate portion 229 A ( FIG. 47 ) having a diameter substantially the same as the remainder of the expander pin, with transverse bores 227 being formed in the cylindrical intermediate portion 229 A.
Looking next at FIGS. 50-53 , in one preferred method of use, shaft 300 and expandable body 100 are driven into bone, and then a piece of suture 228 is looped around the soft tissue 600 which is to be attached to the bone 700 ( FIG. 50 ). Then the suture 228 is pulled taut so as to bring the soft tissue into close proximity to the fastener ( FIG. 51 ). Then pusher 400 is driven distally ( FIG. 52 ) so as to completely set the fastener. At this point, since suture 228 is attached to expander pin 200 intermediate the length of the expander pin, the suture will be fixed in place relative to the deployed expander pin and, hence, will secure soft tissue 600 to bone 700 . Installation tool 15 is then removed from the surgical site by unscrewing shaft 300 from expandable body 100 ( FIG. 53 ).
If desired, expander pin 200 can also be formed so that its suture-receiving bores 227 are located adjacent to the distal end of the expander pin. For example, in another preferred form of the invention, expander pin 200 includes a cylindrical distal end portion 229 B ( FIG. 54 ) having a diameter substantially the same as the remainder of the expander pin, with transverse bores 227 being formed in the cylindrical distal end portion.
Looking next at FIGS. 55 and 56 , there is shown a removal tool 800 . Removal tool 800 can be used to remove a previously-deployed fastener 10 , if the same should prove necessary or desirable. Removal tool 800 generally comprises a shaft 805 having a reverse thread 810 formed on its distal end and a handle 815 formed on its proximal end. The distal end of removal tool 800 is sized so as to be significantly larger than the longitudinal passageway 230 ( FIG. 16 ) formed in expander pin 200 .
When a previously-deployed fastener 10 is to be removed, the distal end of removal tool 800 is screwed into the proximal end of expander pin 200 using the removal tool's reverse screw thread 810 . Inasmuch as the distal end of the removal tool is significantly larger than the longitudinal passageway 230 formed in expander pin 200 , this action will cause the removal tool's distal threads 815 to force their way into the side wall of expander pin 200 and, depending on the sizing of the removal tool, possibly into the side wall of expandable body 100 as well. In any case, as the reverse thread 810 of the removal tool is screwed into the expander pin, continued reverse screwing will eventually cause the normally-threaded expander pin 200 to unscrew itself from expandable body 100 . Removal tool 800 may then be used to remove expander pin 200 from expandable body 100 . Expandable body 100 may then itself be removed from the surgical site by passing shaft 300 back into the interior of expandable body. 100 , screwing the shaft's threads 315 into the expandable body's threaded section 140 , and then removing the shaft and expandable body from the bone. | Apparatuses for attaching tissue to bone are provided. In one exemplary embodiment, the apparatus includes an expandable body defining a bore, an expander pin having a shaft sized to be received in the bore of the expandable body, and an insertion shaft slidingly disposed in the bore of the expandable body and in a bore of the expander pin. The body is configured to expand laterally into and attach to bone when the expander pin is driven into the expandable body. The body includes a proximal main member having a distally extending threaded projection and a harder, distal tip member having a threaded recess in a proximal surface thereof such that the projection is threadedly interengageable with the recess. The expansion of the body by way of the expander pin can occur when the proximal main member and distal tip member are threadedly engaged. The insertion shaft is releasably secured to the expandable body and extends distally beyond the expandable body. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to a latching circuit which is described more particularly as a clocked latching circuit.
In the prior art, a digital latching circuit includes input and latching pairs of emitter-coupled transistors. The input and latching pairs of transistors are responsive to states of input signals representing data bits for producing output signals having the binary value of the input signals but controlled by a clock cycle. Pulses of current are applied alternately to the common emitter circuits of the input and output pairs for alternately quantizing the state of the input signal and latching that quantized state.
There are several problems with the prior art latching circuit. When more latches than one are cascaded, level shifting is required between those latches. Such level shifting circuitry reduces speed of operation and increases propagation delay. The prior art latching circuit also is slowed because it is biased near saturation. Additionally the prior art latching circuit is highly sensitive to supply voltage level.
SUMMARY OF THE INVENTION
These problems are overcome by a clocked latching circuit including a quantizer having an input pair of emitter-coupled transistors connected to output transimpedance circuits. The quantizer is responsive to the state of an input signal applied to the input pair for producing, from the output transimpedance circuits, a quantized output signal. A feedback pair of emitter-coupled transistors is interposed between the outputs of the transimpedance circuits and the inputs to the transimpedance circuits. Current pulses are applied alternatively to the common emitter circuits of the input pair of transistors and of the feedback pair of transistors for alternatively enabling the quantizing of the state of the input signal and the latching of that quantized state.
BRIEF DESCRIPTION OF THE DRAWING
A better understanding of the arrangement and operation of the invention may be derived by reading the following detailed description with reference to the drawing wherein
FIG. 1 is a schematic diagram of a clocked latching circuit; and
FIGS. 2, 3 and 4 are schematic diagrams of parts of the circuit of FIG. 1 during various operating conditions.
DETAILED DESCRIPTION
Referring now to FIG. 1, there is shown a clocked latching circuit 10 including a quantizer having an input pair of emitter-coupled NPN transistors 11 and 12 and a pair of output transimpedance circuits. Balanced input data signals are applied to input terminals 13 which connect directly to base electrodes of the input pair of transistors 11 and 12.
A first transimpedance circuit, connected in the collector circuit of the transistor 11, includes a diode 14 and a PNP transistor 15 arranged with resistors 17 and 18 as a current mirror. A load resistor 19 is connected between the output collector electrode of the transistor 15 and ground potential 20.
A second transimpedance circuit, connected in the collector circuit of the transistor 12, includes a diode 24 and a PNP transistor 25 arranged with resistors 27 and 28 as another current mirror. A load resistor 29 is connected between the output collector electrode of the transistor 25 and ground potential 20.
It is noted that the first and second transimpedance circuits include the PNP transistors 15 and 25 which provide some valuable benefits during operation. By being opposite conductivity bype devices from the input pair of emitter-coupled NPN transistors 11 and 12, the transimpedance circuits avoid the use of level shifting devices which would slow down operation. Also because of the opposite conductivity type devices from the input pair, the base-collector junctions of the transistors of the transimpedance circuits float with respect to bias voltage as explained subsequently herein.
Output signals are produced on output terminals 30 which are connected with the collector electrodes of the transistors 15 and 25.
The circuit nodes connecting the output collector electrodes of the transistors 15 and 25 with the output terminals 30 also are connected with input base electrodes of a feedback pair of emitter-coupled NPN transistors 31 and 32. The output collector electrodes of the feedback pair of transistors 31 and 32 are connected, respectively, both to the collector electrodes of the input transistors 11 and 12 and to the input base electrodes of the transistors 15 and 25 of the transimpedance circuits.
A source 40 of positive polarity bias potential is connected to the resistors 17, 18, 27 and 28 in the transimpedance circuits. The input and feedback pairs of emitter-coupled transistors and the opposite conductivity type of transistors of the transimpedance circuits are interconnected so that the base-collector junctions of the feedback pair of transistors and of the transistors of the transimpedance circuits are floating with respect to bias voltage. Thus those transistors are biased so that output voltage signals produced by the opposite conductivity type transistors of the transimpedance circuits are independent of the bias voltage level over a wide range.
Common emitter circuits of the input pair of transistors 11 and 12 and of the feedback pair of transistors 31 and 32 are connected with complementary clock current sources 41 and 42, respectively. The clocked current sources 41 and 42 control operation of the latching circuit by controlling the common emitter current I CL conducted from the transistors 11 and 12 to a source 50 of negative polarity bias potential and the common emitter current I CL conducted from the transistors 31 and 32 also to the source 50.
During operation there are three operating states which are determined by the clocked common emitter currents. Those states are an unlatched state, a dynamic state and a regenerative, or latching, state. Circuit functions which occur during each of these states are to be described subsequently.
Referring now to FIG. 2, there is shown a schematic of the effective parts of the circuit of FIG. 1 during the unlatched state. The input pair of emitter-coupled transistors is separated from the transistors 15 and 25 for clarity. The unlatched state occurs when the clock current I CL has a maximum steady state magnitude while the complementary clock current signal I CL is zero. Since there is no complementary clock current I CL , the transistors 31 and 32 are inoperative and are omitted from the schematic. During this unlatched state, the input pair of transistors 11 and 12 and the transistors 15 and 25 operate to amplify and limit the input signals applied to the input terminals 13. With respect to large amplitude input signals, the transistors 11, 12, 15 and 25 operate nonlinearly but not in saturation. The unlatched state is the state of operation of the circuit 10 during which new data is applied to the input. In the unlatched state, the latch circuit 10 acts like a quantizer. Output signals are a quantized version of the input signals and are produced at the output terminals 30. Thus the state of the input data signal which is applied to the input terminals 13 is quantized by the input transistors 11 and 12 and are mirrored to the output terminals 30 by way of transimpedance circuits.
Referring now to FIG. 3, there is shown the schematic of the effective circuit of FIG. 1 during the dynamic state. The three pairs of transistors are shown separated from one another for clarity. The dynamic state occurs while the clock currents I CL and I CL are in transition from the unlatched condition wherein the clock current I CL is at maximum amplitude and the complementary clock current I CL is zero to the latch, or opposite, clock current condition. Thus a decreasing clock current I CL is conducted through the common emitter circuits of the transistors 11 and 12. An increasing complementary clock current I CL is conducted through the common emitter circuits of the feedback transistors 31 and 32. Both of the clock currents I CL and I CL are shown as varying currents in FIG. 3.
This dynamic state provides an interval during which the new data, applied to the input during the unlatched state, is latched into the latch circuit 10. Current mirror arrangements of the opposite conductivity type transimpedance circuits, change the polarity of the collector output currents from the input pair of emitter-coupled transistors. Storage time of the transimpedance circuit arrangements is sufficiently long to assure that the latch circuit 10 retains the state of the new data while the clock currents are switched from the unlatched state to the latched state. During the dynamic state, all of the transistors 11, 12, 15, 25, 31 and 32 are operated under various operating conditions because the varying clock currents dynamically change the bias conditions. The clocked latching circuit 10 decides during the dynamic state whether the input signal represents a one or a zero bit.
Referring now to FIG. 4, there is shown a schematic of the effective parts of the circuit of FIG. 1 during the latched, or regenerative, state. The feedback pair of transistors 31 and 32 is separated from the transistors 15 and 25 for clarity. The latched, or regenerative, state occurs while the complementary clock current I CL has a maximum steady state magnitude while the clock current I CL is zero. During this latched state, the input pair of emitter-coupled transistors 11 and 12 is inoperative because there is no clock current I CL supplied to their common emitter circuit. The transistors 11 and 12 therefore are omitted from the schematic. The transistors 15 and 25 and the feedback pair of transistors 31 and 32 operate in a regenerative, or latched, state with respect to the signal stored at the output terminals 30 upon the termination of the unlatched state. Throughout the latched state, these signals are retained by the regenerative action of the transimpedance circuits and the latching pair of transistors 31 and 32.
Whatever state is latched into the clocked latching circuit 10, causes complementary output signals to be produced on the output terminals 30 and held for application to any circuit connected to those terminals. These output signals may be used as single-ended or as balanced output signals.
It is noted that the conductivities of the transistors can be interchanged. Care must be taken to alter polarities accordingly throughout the circuit.
It is advantageous to fabricate the latching circuit 10 as an integrated circuit. There are known processes for fabricating the opposite conductivity type transistors in a monolithic integrated circuit capable of operating at frequencies as high as the microwave frequency range. One process which can be used for making the circuit is a process described in a now abandoned U.S. patent application Ser. No. 658,586, filed on Feb. 17, 1976 in the names of W. E. Beadle, S. F. Moyer, and A. A. Yiannoulos and entitled "Integrated Complementary Vertical Transistors." Another process which can be used for making the circuit is a slightly modified version of the just mentioned process, which is described in a U.S. patent application, Ser. No. 337,707, filed on Jan. 7, 1982 in the name of D. G. Ross.
The foregoing describes an illustrative embodiment of the invention. The described embodiment together with other embodiments which are obvious to those skilled in the art are considered to be within the scope of the invention. | A digital latching circuit includes a quantizer having an input pair of emitter-coupled transistors connected with output transimpedance circuits. The quantizer is responsive to the state of an input signal applied to the input pair for producing from the output transimpedance circuits a quantized output signal. A feedback pair of emitter-coupled transistors is interposed between the outputs of the transimpedance circuits and the inputs to the transimpedance circuits. Current pulses are applied alternatively to the common emitter circuits of the input pair and the feedback pair of transistors for alternatively enabling the quantizing of the state of the input signal and the latching of that quantized state. | 7 |
TECHNICAL FIELD
[0001] The present invention relates to an inverter-integrated electric compressor in which an inverter device is integrally incorporated into a housing of the electric compressor.
BACKGROUND ART
[0002] Inverter-integrated electric compressors, which integrally incorporate inverter devices, are used as air conditioner compressors installed in electric vehicles, hybrid vehicles, and the like. Such inverter-integrated electric compressors are configured so that high voltage direct current power supplied from a power supply unit installed in the vehicle is converted by an inverter device to three-phase alternating current power of a specified frequency, which is then applied to the electric motor so as to drive the electric motor.
[0003] The inverter device comprises a plurality of high-voltage electrical components, such as a coil and a capacitor, constituting a noise-removing filter circuit, a plurality of semiconductor switching elements, such as IGBTs, constituting a switching circuit for converting power, an inverter circuit including the filter circuit and the switching circuit, and a circuit board on which a control circuit of the inverter circuit is mounted, and is used to convert direct current power inputted via a P-N terminal into three-phase alternating current power, and output the three-phase alternating current power from a UWV terminal to the motor. The inverter device is incorporated into an inverter housing section provided on the outer circumference of a housing of the electric compressor, thereby integrating the inverter device into the compressor.
[0004] A power source cable for supplying direct current power from a power source to the inverter device, as disclosed, for example, in Patent Document 1, is configured so as to connect via a connector of the power source cable to a connector connection section provided on the inverter housing section side, and from there to the P-N terminal on the control circuit board side via a resin circuit board comprising a direct current power line constituted by a terminal block and a wiring pattern, a filter circuit constituted by an inductor coil and a smoothing capacitor provided on the resin circuit board, a busbar assembly, and the like.
[0005] Patent Document 2 discloses an arrangement in which a power source input port formation part is formed on a metal inverter cover for closing off an inverter housing space in which is disposed a circuit board on which are mounted a coil and capacitor for a filter circuit, a metal terminal is resin insert molded at the port formation part to provide an integrated resin power source connector, and a power source cable is connected to the power source connector and anchored to the housing of the inverter cover, thereby connecting the metal terminal of the power source connector to the circuit board. Patent Document 3 discloses an arrangement in which a power converter board is anchored and disposed on an interior surface of a circuit board cover with an elastic member sandwiched therebetween, a coil and capacitor for a filter circuit are disposed on a surface facing a housing, and the lower parts of the coil and condenser are inserted into and disposed in recessions in the housing.
PRIOR ART LITERATURE
Patent Literature
Patent Document 1: Japanese Patent No. 4898931
Patent Document 2: Japanese Unexamined Patent Application Publication No. 2012-193660A
Patent Document 3: Japanese Unexamined Patent Application Publication No. 2007-295639A
SUMMARY OF INVENTION
Problem to be Solved by the Invention
[0006] However, the arrangement disclosed in Patent Document 1 presents problems in that it is necessary to provide the direct-current power input system from the power source cable with a terminal block, resin circuit board, busbar, and the like, and connect the high-voltage electrical components, such as the filter circuit coil and smoothing capacitor, thus increasing the number of parts in the inverter device, complicating the configuration thereof, and increasing costs and size; and, because a busbar connecting section is necessary, it is difficult to ensure reliability.
[0007] In the arrangement disclosed in Patent Document 2, a plurality of electrical components for use in the filter circuit is mounted on the circuit board, and an integrated power source connector for connecting the power source cable to the inverter cover is provided; the metal terminal thereof need only be connected to the circuit board when the inverter cover is being mounted, thus allowing the configuration of the direct-current power input system to be simplified. However, there is a problem in that excess force may be placed upon the circuit board when the terminal is inserted when connecting the metal terminal to the circuit board, leading to the risk of the stress caused thereby damaging the circuit board or damaging the mounting components. Patent Document 3 discloses an arrangement in which a coil and capacitor are disposed on the rear side of the power converter board; however, this arrangement does not alleviate the stress placed upon the circuit board during terminal insertion as described above.
[0008] The present invention was conceived in view of the circumstances described above, and has an object of providing an inverter-integrated electric compressor in which stress placed upon a main circuit board is borne and alleviated by a high-voltage electrical component even upon a connector of a power source cable being directly connected to a P-N terminal provided on the main circuit board, the bearing of stress being effected at high precision.
Solution to Problem
[0009] The inverter-integrated electric compressor of the present invention employs the following means to solve the problems described above.
[0010] Specifically, an inverter-integrated electric compressor according to one aspect of the present invention is an inverter-integrated electric compressor having an integrated inverter device incorporated in an inverter housing section provided on the outer circumference of a housing, the compressor including a P-N terminal configured to input high-voltage direct-current power provided on a main circuit board of the inverter device, a power source cable being able to be connected by inserting a connector provided at one end of the cable into the P-N terminal; a high-voltage electrical component constituting the inverter device provided at a position across from the P-N terminal on the opposite side of the main circuit board; the electrical component being housed within a case and anchored in place by a resin material, a plurality of raised and recessed sections being provided on a circumferential edge of an opening in an upper end of the case, and the raised sections being brought into contact with the undersurface of the main circuit board so as to bear stress placed upon the main circuit board when the connector is inserted.
[0011] In accordance with the aspect described above, the P-N terminal configured to input high-voltage direct-current power is provided on the main circuit board of the inverter device, and the power source cable is able to be connected by inserting the connector provided at one end of the cable into the P-N terminal; a high-voltage electrical component constituting the inverter device is provided at a position across from the P-N terminal on the opposite side of the main circuit board; the electrical component is housed within the case and anchored in place by the resin material, a plurality of raised and recessed sections is provided on a circumferential edge of an opening in the upper end of the case, and the raised sections are brought into contact with the undersurface of the main circuit board so as to bear stress placed upon the main circuit board when the connector is inserted, thus allowing stress placed upon the main circuit board when the connector is inserted to be alleviated by being borne by the high-voltage electrical component disposed at a position across from the P-N terminal on the opposite side of the main circuit board, even in arrangements in which the power source cable is directly connected to the P-N terminal provided on the main circuit board by inserting the connector provided at one end of the power source cable. It is thus possible to reliably eliminate occurrence of damage to the main circuit board or the components mounted thereupon due to stress caused by exerting excessive pressing force when inserting the connector. In addition, the terminal block, busbar, and the like previously provided in the direct-current power input system are omitted, reducing the number of components in the inverter device, with the result that device configuration can be simplified, costs, size, and weight can be reduced, and the reduction in the number of busbar connections allows for a reduction in the number of manufacturing steps and improved reliability. The provision of a plurality of raised and recessed sections on the circumferential edge of the opening in the upper end of the case housing the electrical component, with the raised sections thereof supporting the undersurface of the main circuit board, allows any resin material filling the case that overflows when the electrical component is housed in the case and anchored in place with resin material to escape through the recessed sections, thereby making it possible to maintain the dimensional precision of the upper surfaces of the raised sections supporting the circuit board, support the main circuit board with high precision, and ensure inverter device assembly precision.
[0012] An inverter-integrated electric compressor according to one aspect of the present invention may be the inverter-integrated electric compressor described above, wherein the electrical component is a smoothing capacitor constituting a noise-removing filter circuit provided on a high-voltage direct-current power line of the inverter device.
[0013] In accordance with this aspect, the electrical component is a smoothing capacitor constituting a noise-removing filter circuit provided on a high-voltage direct-current power line of the inverter device, thereby allowing the smoothing capacitor, which is housed within the case and has a square outline, to be disposed at a position across from the P-N terminal on the opposite side of the main circuit board, with the result that the capacitor can be used without modification as an electrical component that stably bears stress placed upon the main circuit board. Accordingly, by using an existing electrical component and modifying the manner in which the component is disposed so that it can be used as a member for bearing stress placed upon the main circuit board, an arrangement in which a power source cable is directly connected to the P-N terminal provided on the main circuit board is made possible, allowing the number of parts, cost, size, weight, and the like of the inverter device to be reduced.
[0014] An inverter-integrated electric compressor according to one aspect of the present invention may be the inverter-integrated electric compressor described above, wherein the electrical component is a coil constituting a noise-removing filter circuit provided on a high-voltage direct-current power line of the inverter device.
[0015] In accordance with this aspect, the electrical component is a coil constituting a noise-removing filter circuit provided on a high-voltage direct-current power line of the inverter device, thereby allowing the coil housed within the case, which has a flat upper surface, to be disposed at a position across from the P-N terminal on the opposite side of the main circuit board, with the result that the capacitor can be used without modification as an electrical component that stably bears stress placed upon the main circuit board. Accordingly, by using an existing electrical component and modifying the manner in which the component is disposed so that it can be used as a member for bearing stress placed upon the main circuit board, an arrangement in which a power source cable is directly connected to the P-N terminal provided on the main circuit board is made possible, allowing the number of parts, cost, size, weight, and the like of the inverter device to be reduced.
[0016] An inverter-integrated electric compressor according to another aspect of the present invention may be any of the inverter-integrated electric compressors described above, wherein the case housing the electrical component has a rectangular shape as seen in plan view, and the plurality of raised and recessed sections provided on the circumferential edge of the opening in the upper end thereof are provided in alternation and so that at least one raised section is present on each side of the opening.
[0017] In accordance with this aspect, the case housing the electrical component has a rectangular shape as seen in plan view, and the plurality of raised and recessed sections provided on the circumferential edge of the opening in the upper end thereof is provided in alternation and so that at least one raised section is present on each side of the opening, thereby allowing stress placed upon the main circuit board when the connector is inserted into the P-N terminal to be dispersed and borne by the one or more raised sections provided on each of the rectangle-forming circumferential edge of the case housing the electrical component, and ensuring the dimensional precision of the upper surfaces of the raised sections supporting the circuit board by allowing any resin material filling the case that overflows when the electrical component is housed within the case and anchored with resin material during fabrication to escape through the recessed sections. Accordingly, stress placed upon the main circuit board can be greatly mitigated, damage to the main circuit board or the components mounted thereupon can be reliably prevented, the main circuit board can be supported evenly and with high precision and precision in assembling the inverter device can be ensured.
[0018] An inverter-integrated electric compressor according to another aspect of the present invention may be any of the inverter-integrated electric compressors described above, wherein the connector provided at one end of the power source cable is provided at a position corresponding to that of the P-N terminal on the side of a lid for closing off the inverter housing section, and can be inserted into the P-N terminal when the lid is mounted in place.
[0019] In accordance with this aspect, the connector provided at one end of the power source cable is provided at a position corresponding to that of the P-N terminal on the side of the lid for closing off the inverter housing section, and can be inserted into the P-N terminal when the lid is mounted in place, with the result that, after the inverter device has been housed and set in position, the power source cable can be simultaneously connected to the P-N terminal of the inverter device as the lid is mounted in place, thus closing off the inverter housing section, by inserting the connector disposed on the inner surface of the lid into the P-N terminal. As a result, the connection structure of the power source cable and the process of connecting the cable can be simplified, and the connector can be reliably inserted into the P-N terminal without placing excessive stress upon the main circuit board even if the connector is engaged by pressing on the lid with somewhat excessive force.
Advantageous Effect of Invention
[0020] In accordance with the present invention, stress placed upon the main circuit board when the connector provided at one end of the power source cable is inserted into the P-N terminal provided on the main circuit board is alleviated by being borne by the high-voltage electrical component disposed at a position across from the P-N terminal on the opposite side of the main circuit board, even in arrangements in which the power source cable is directly connected via the insertion of the connector, thereby allowing for the reliable elimination of occurrence of damage to the main circuit board or the components mounted thereupon due to stress caused by excessive pressing force when inserting the connector. In addition, the terminal block, busbar, and the like previously provided in the direct-current power input system are omitted, reducing the number of components in the inverter device, with the results that device configuration can be simplified, costs, size, and weight can be reduced, and the reduction in the number of busbar connections allows for a reduction in the number of manufacturing steps and improved reliability. In addition, the provision of a plurality of raised and recessed sections on the circumferential edge of the opening in the upper end of the case housing the electrical component, with the raised sections thereof supporting the undersurface of the main circuit board, allows any resin material filling the case that overflows when the electrical component is housed in the case and anchored in place with resin material to escape through the recessed sections, thereby making it possible to maintain the dimensional precision of the upper surfaces of the raised sections supporting the circuit board, support the main circuit board with high precision, and ensure inverter device assembly precision.
BRIEF DESCRIPTION OF DRAWINGS
[0021] FIG. 1 is a perspective view illustrating a configuration of the main components of an inverter-integrated electric compressor according to an embodiment of the present invention.
[0022] FIG. 2 is a corresponding longitudinal cross-sectional view along line a-a in FIG. 1 .
[0023] FIG. 3 is a perspective rear view of a lid that closes off an inverter housing section of the inverter-integrated electric compressor.
[0024] FIG. 4 is a perspective view of a power source cable unit connected to the lid.
[0025] FIG. 5 is an exploded perspective view illustrating the relative positions of a main circuit board of the inverter device and a high-voltage electrical component arranged on the rear side of the main circuit board.
[0026] FIG. 6 is a perspective view of the high-voltage electrical component (smoothing capacitor) arranged at a position across from a P-N terminal on the main circuit board.
DESCRIPTION OF EMBODIMENTS
[0027] An embodiment of the present invention will be described below with reference to FIGS. 1 to 6 .
[0028] FIG. 1 is a perspective view of main components of an inverter-integrated electric compressor according to an embodiment of the present invention, FIG. 2 is a longitudinal cross-sectional view along line a-a in FIG. 1 , FIG. 3 is a perspective rear view of a lid that closes off an inverter housing section, and FIG. 4 is a perspective view of a power source cable unit.
[0029] An inverter-integrated electric compressor 1 is provided with a cylindrical housing 2 constituting an outer shell. The housing 2 is constituted by a motor housing 3 into which an electric motor (not illustrated) is built, and a compressor housing (not illustrated) into which a compression mechanism (not illustrated) is built, the two housings being joined together into a single whole.
[0030] The inverter-integrated electric compressor 1 is configured so that the electric motor and compression mechanism built into the housing 2 are linked by a rotary shaft, and the compression mechanism is driven when the electric motor is rotationally driven via an inverter device 7 described below, thereby causing low-pressure refrigerant gas that has been drawn into the interior of the motor housing 3 via an intake port 4 disposed in a side wall on the rear end of the motor housing 3 to be drawn in around the electric motor, compressed to a high pressure by the compression mechanism, discharged within the compressor housing, and then expelled to the outside.
[0031] A plurality of refrigerant flow paths 5 are formed in the motor housing 3 so as to allow refrigerant to flow in the axial direction along the inner circumferential surface thereof, and a plurality of legs 6 for installing the electric compressor 1 are provided on the outer circumference thereof. An inverter housing section 8 into which the inverter device 7 can be integrally incorporated is integrally formed on the outer circumference of the housing 2 (on the motor housing 3 side). The inverter housing section 8 has a roughly square shape as seen in plan view and is configured so that the bottom surface thereof constitutes a partially substantially flat seating face 9 formed by the wall of the motor housing 3 , and a flange 10 extends upward at the perimeter thereof.
[0032] The inverter housing section 8 is configured so as to be closed off by mounting a lid 11 on the flange 10 , as illustrated in FIG. 3 , after the inverter device 7 has been incorporated. A high-voltage cable (power source cable) 12 is provided on the inner surface of the lid 11 . The high-voltage cable 12 has a connector 13 provided at one end thereof and a connector terminal 14 for connecting to a power source cable at the other end thereof. The connector 13 at one end is anchored in place on the inner surface of the lid 11 by a screw 15 at a position corresponding to a P-N terminal 24 provided upon a main circuit board 20 , to be described hereafter, and the connector terminal 14 on the other end is anchored in place from the outer side by a plurality of screws 16 , with the terminal portion protruding toward the outer surface of the lid 11 .
[0033] The high-voltage cable 12 constitutes the power source cable and is connected via the power source cable to a power supply unit installed in the vehicle, and the connector 13 provided at one end thereof is for applying high-voltage direct-current power supplied from the power supply unit to the inverter device 7 by connecting to the P-N terminal 24 provided on the main circuit board 20 of the inverter device 7 .
[0034] The inverter device 7 drives the electric motor by converting high-voltage direct-current power supplied from the power supply unit installed in the vehicle into three-phase alternating-current power of a specified frequency, and then applying the same to the electric motor. As illustrated in FIGS. 1 and 2 , the inverter device 7 is integrated and incorporated into the inverter housing section 8 , and is constituted by a plurality of high-voltage electrical components (hereinafter, also referred to simply as “electrical components”) making up a noise-removing filter circuit, such as a coil 17 and a smoothing capacitor 18 housed within a case, a sub-circuit board 19 , the main circuit board 20 , and the like.
[0035] The inverter device 7 itself may be one known in the art; in this description, a device is used in which the plurality of electrical components making up the filter circuit, such as the coil 17 and the smoothing capacitor 18 , are mounted to the main circuit board 20 via soldering to yield an integrated whole. The smoothing capacitor 18 is typically configured so as to be housed in a case. As illustrated in FIGS. 2 and 6 , the smoothing capacitor 18 has a square (cuboid) outline, and the upper surface thereof has a substantially flat, planar shape. The electrical components such as the smoothing capacitor 18 and the coil 17 (for example, a common mode coil or normal mode coil) housed within the case are connected to a high voltage line formed by a wiring pattern on the main circuit board 20 , and constitute a known noise-removing filter circuit.
[0036] A communication circuit 21 that is connected to a communication line extending from a host controller is mounted on the sub-circuit board 19 , which is anchored in place in contact with the seating face 9 formed on a wall of the motor housing 3 constituting the bottom surface of the inverter housing section 8 . The sub-circuit board 19 is electrically connected to the main circuit board 20 .
[0037] A switching circuit (not illustrated) constituted by a plurality of switching elements such as IGBTs for converting direct-current power to three-phase alternating-current power is mounted on the main circuit board 20 , as is a control circuit 22 that operates at low voltage, such as a CPU, for controlling the switching circuit and the like. The main circuit board 20 controls the operation of the inverter device 7 based on a control signal from an ECU installed on the vehicle, and is anchored in place within the inverter housing section 8 by a plurality of bolts 23 . A P-N terminal 24 for inputting high-voltage direct-current power from the high-voltage cable 12 via the connector 13 and a UVW terminal 25 for outputting three-phase alternating-current power of a specified frequency that has been converted from the direct-current power are provided on the upper surface of the main circuit board 20 .
[0038] The UVW terminal 25 is connected to a glass-sealed terminal 26 installed in the inverter housing section 8 that passes through the motor housing 3 , and applies three-phase alternating-current power to the electric motor disposed within the motor housing 3 via the glass-sealed terminal 26 .
[0039] The connector 13 provided on the lid 11 in correspondence with the P-N terminal 24 is inserted into the P-N terminal 24 so that the high-voltage line is connected; at least a certain degree of pressing force is necessary when inserting the connector 13 , and the stress thereof is exerted on the main circuit board 20 .
[0040] In the present embodiment, as illustrated in FIG. 5 , the smoothing capacitor 18 constituting one of the high-voltage electrical components is provided on the rear side of the main circuit board 20 across from the position at which the P-N terminal 24 is disposed so as to bear the stress placed upon the main circuit board 20 . The smoothing capacitor 18 has a square (cuboid) outline, and is configured so that the upper surface thereof bears stress applied to the main circuit board 20 . As illustrated in FIG. 6 , the smoothing capacitor 18 is housed within a resin case 27 having an open upper end, and is anchored therein by resin material 28 filling the case. A pair of terminals 29 protrudes from the surface of the resin material 28 , and the smoothing capacitor 18 is mounted to the main circuit board 20 by soldering the terminals 29 to the main circuit board 20 .
[0041] A plurality of recessed sections 30 and raised sections 31 are alternatingly provided on the circumferential edge of the opening in the rectangular upper end of the case 27 housing the smoothing capacitor 18 so that at least one raised section 31 is present on each side of the opening. The raised sections 31 support the underside of the main circuit board 20 at a position across from the P-N terminal 24 disposed on the upper surface of the main circuit board 20 , and bear stress placed upon the main circuit board 20 when the connector 13 is inserted into the P-N terminal 24 ; meanwhile, the recessed sections 30 allow any resin material 28 filling the case 27 that overflows to escape therethrough when the smoothing capacitor 18 is being fabricated, thereby keeping the resin material 28 from affecting the dimensional precision of the upper surfaces of the raised sections 31 .
[0042] The coil 17 constituting another of the high-voltage electrical components is housed in a resin case 32 having a roughly flat, planar upper surface, like the case 27 of the smoothing capacitor 18 and similarly anchored therein by a resin material, and is mounted to the main circuit board 20 by soldering both terminals 33 to the main circuit board 20 . The cases 27 , 32 of the coil 17 and the smoothing capacitor 18 are fastened in place by screws 34 , 35 (see FIG. 1 ) at predetermined positions to the rear side of the main circuit board 20 , allowing the coil 17 and smoothing capacitor 18 to be housed in the inverter housing section 8 along with the main circuit board 20 as an integrated whole, with the bottom portions thereof being anchored in place on the bottom surface of the inverter housing section 8 by a silicon adhesive or the like.
[0043] In the present embodiment, as described above, the smoothing capacitor 18 constituting one of the high-voltage electrical components constituting the inverter device 7 is disposed at a position on the rear side of the main circuit board 20 across from the P-N terminal 24 provided upon the main circuit board 20 , the plurality of recessed sections 30 and raised sections 31 is provided on the circumferential edge of the opening in the upper end of the housing case 27 of the smoothing capacitor 18 , and the raised sections 31 contact the undersurface of the main circuit board 20 , thereby bearing stress placed upon the main circuit board 20 when the connector 13 is inserted into the P-N terminal 24 . The smoothing capacitor 18 is thus capable of bearing stress upon the main circuit board 20 even when the connector 13 is inserted into the P-N terminal 24 with excessive pressing force.
[0044] Thus, in accordance with the present embodiment, stress placed upon the main circuit board 20 when the connector 13 provided at one end of the power source cable 12 is inserted into the P-N terminal 24 provided on the main circuit board 20 can be greatly reduced by bearing borne by the smoothing capacitor 18 constituting one of the high-voltage electrical components disposed at a position across from the P-N terminal 24 on the opposite side of the main circuit board 20 , even when the power source cable 12 is directly connected to the main circuit board 20 via insertion of the connector 13 .
[0045] It is thus possible to reliably eliminate the occurrence of damage and the like to the main circuit board 20 or the components mounted thereupon due to stress caused by exerting excessive pressing force when inserting the connector 13 . In addition, the terminal block, busbar, and the like previously provided in the direct-current power input system are omitted, reducing the number of components in the inverter device 7 , with the results that device configuration can be simplified, costs, size, and weight can be reduced, and the reduction in the number of busbar connections allows for a reduction in the number of manufacturing steps and improved reliability.
[0046] Because the plurality of raised and recessed sections (recessed sections 30 and raised sections 31 ) are provided on the circumferential edge of the opening in the upper end of the case 27 housing the smoothing capacitor 18 constituting one of the high-voltage electrical components, and the raised sections 31 support the undersurface of the main circuit board 20 , any resin material 28 filling the case 27 that overflows can escape through the recessed sections 30 when the smoothing capacitor 18 is housed within the case 27 and anchored by the resin material 28 , thus making it possible to eliminate any effects on the part of the resin material 28 , maintain the dimensional precision of the upper surfaces of the raised sections 31 supporting the main circuit board 20 , support the main circuit board 20 with high precision, and ensure precision in assembling the inverter device 7 .
[0047] In the present embodiment, the high-voltage electrical component bearing stress placed upon the main circuit board 20 is the smoothing capacitor 18 constituting the noise-removing filter circuit provided on the high-voltage direct-current power line of the inverter device 7 . Thus, the provision of the smoothing capacitor 18 , which typically is housed within the case 27 and has a square outline, at a position across from the P-N terminal 24 on the opposite side of the main circuit board 20 allows the smoothing capacitor 18 to be used without modification as an electrical component for bearing stress placed upon the main circuit board 20 .
[0048] Using an existing high-voltage electrical component constituting the filter circuit and modifying the manner in which the component is disposed so that it can be used as a member for bearing stress placed upon the main circuit board 20 in this way allows for an arrangement in which the connector 13 provided at one end of the power source cable 12 is directly connected to the P-N terminal 24 provided on the main circuit board 20 , thereby allowing the number of parts, cost, size, weight, and the like of the inverter device 7 to be reduced.
[0049] The case 27 of the smoothing capacitor 18 has a rectangular shape as seen in plan view, and the plurality of recessed sections 30 and raised sections 31 provided on the circumferential edge of the opening in the upper end thereof are provided in alternation and so that at least one raised section 31 is present on each side. As a result, stress placed upon the main circuit board 20 when the connector 13 is inserted into the P-N terminal 24 can be dispersed and borne by the one or more raised sections 31 provided on each side of the rectangle-forming circumferential edge of the case 27 , and any resin material 28 filling the case 27 that overflows when the smoothing capacitor 18 is housed within the case 27 and anchored by the resin material 28 during fabrication escapes through the recessed sections 30 , thereby ensuring the dimensional precision of the upper surfaces of the raised sections 31 supporting the main circuit board 20 .
[0050] Accordingly, stress placed upon the main circuit board 20 can be greatly mitigated, damage to the main circuit board 20 or the components mounted thereupon can be reliably prevented, the main circuit board 20 can be supported evenly and with high precision, and precision in assembling the inverter device 7 can be ensured.
[0051] The connector 13 provided at one end of the power source cable 12 is provided at a position corresponding to that of the P-N terminal 24 on the side of the lid 11 closing off the inverter housing section 8 , and can be inserted into the P-N terminal 24 when the lid 11 is mounted into place. As a result, after the inverter device 7 has been set in position, the power source cable 12 can be simultaneously connected to the P-N terminal 24 of the inverter device 7 as the lid 11 is mounted in place, thus closing off the inverter housing section 8 , by inserting the connector 13 disposed on the inner surface of the lid 11 into the P-N terminal 24 . Accordingly, the connection structure of the power source cable 12 and the process of connecting the cable can be simplified, and the connector 13 can be reliably inserted into the P-N terminal 24 without the risk of placing excessive stress upon the main circuit board 20 even if the connector 13 is engaged by pressing on the lid 11 with somewhat excessive force.
[0052] The present invention is not limited to the invention according to the embodiment described above, and modifications can be made thereto as appropriate without departing from the gist thereof. For example, in the embodiment described above, an example has been described in which the electrical component disposed across from the P-N terminal 24 on the opposite side of the main circuit board 20 is the smoothing capacitor 18 , but the present invention is not limited to such an arrangement; for example, the component may be the coil 17 , such as a common mode coil or a normal mode coil, housed within the case 32 , with the case 32 supporting the main circuit board 20 , and effects similar to those described above can be obtained by adopting an arrangement for the case 32 in which a plurality of raised and recessed sections is provided on the circumferential edge of the opening in the upper end thereof, similarly to the case 27 of the smoothing capacitor 18 .
[0053] In the foregoing description, the power source cable takes the form of the high-voltage cable 12 , disposed inside the lid 11 , to which a cable of the power source is connected, but a single cable may of course also be used. The inverter device 7 may be configured in any way as long as the P-N terminal 24 is provided on the main circuit board 20 and the power source cable is connected thereto. For example, the inverter device 7 may be configured as an integrated unit by means of a resin structure, and then incorporated into the inverter housing section 8 .
REFERENCE SIGNS LIST
[0000]
1 Inverter-integrated electric compressor
2 Housing
3 Motor housing
7 Inverter device
8 Inverter housing section
11 Lid
12 High-voltage cable (power source cable)
13 Connector
18 Smoothing capacitor (high-voltage electrical component)
20 Main circuit board
24 P-N terminal
27 Case
28 Resin material
30 Recessed section
31 Raised section | The purpose of the present invention is to provide an inverter-integrated electric compressor which, even with the connector of a power source-side cable configured to be connected directly to a P-N terminal on a circuit board, reduces the stress on the circuit board by support by a high voltage electric component and can implement this support with high precision. This inverter-integrated electric compressor is configured such that a P-N terminal for inputting high-voltage DC power is provided on a main circuit board, a power source-side cable can be connected to said P-N terminal by inserting a connector provided on one end, a high-voltage electric component configuring the inverter device is arranged in the facing position on the side of the main circuit board opposite that of the P-N terminal, and the electric component is housed in a case and fixed by a resin member; and is further configured such that multiple protruding and receding portions are formed on the edge of the top opening of the case, and stress on the main circuit board when the connector is plugged in is received by the protruding portions abutting against the bottom surface of the main circuit board. | 7 |
BACKGROUND OF THE INVENTION
The present invention relates to a tubular knit fabric like gloves knitted by operating a flat knitting machine and a method of executing specific processes to prevent wrist-edge domains of the tubular knit fabric from incurring disintegration of stitched yarns.
Conventionally, gloves are knitted by operating a glove knitting machine in those sequential orders cited below. Initially, four finger domains corresponding to the little finger, third finger, middle finger, and the forefinger, are respectively formed, followed by formation of the four-finger body, the thumb, and the five-finger body. Next, the wrist domains and the wrist-edge aperture domains are automatically knitted before the processed gloves are eventually disengaged from the glove knitting machine.
Nevertheless, those gloves disengaged from the glove knitting machine are not yet complete with the final process for preventing the knitted stitches from disintegrating themselves, and therefore, these gloves are not yet offerable on the market.
Conventionally, wrist-edge aperture domain is treated with a darning process by operating an overlocking machine to prevent the edge yarns from disintegrating themselves. However, in order to execute the darning process, an additional sewing process must be executed after formation of the knitted gloves. This in turn results in an increased cost in the production of gloves.
Therefore, in order to solve the problems inherent in the conventional practice, a variety of methods have thus been proposed by a number of applicants including the applicant related to the invention.
Typically, the proposed method initially forms stitches of several circumferential courses of the knitted terminal including those courses supposed to make up the wrist-edge aperture domain on the way of knitting gloves with those yarns capable of restraining knitted yarns from disintegrating themselves before the formed several-round stitches are subject to a thermal treatment so that the wrist-edge yarns can be prevented from disintegrating themselves.
There are a variety of yarns which are available for preventing wrist-edge stitches from disintegration like the one related to the method proposed by the Japanese Patent Laid-Open Publications No. 58-163703 of 1983, No. 51-122532 of 1976, and others. These methods disclosed in the Japanese Patent Publications No. 60-52222 of 1985 and No. 61-17938 of 1986 are widely made available today.
Concretely, those yarns available for prevention of wrist-edge stitches from incurring disintegration cited for explanation of the above methods are respectively alleged to be free from incurring disintegration by virtue of the execution of those sequential processes including the following: Initially, thermally contractile core-forming elastic yarns are encircled in conjunction with those yarns which are free of thermal fusibility and thermohardening property and available for covering the core elastic yarns, and then, these yarns are superficially added with thermofusing yarns to be encircled in conjunction with the above yarns in the direction opposite from each other. These encircled yarns are made available for composing stitches of several-round courses of the knitted terminal including those courses supposed to make up wrist-edge aperture domain on the way of knitting gloves. This in turn permits intersections between needle loops and sinker loops of stitches of continual courses to adhere to each other due to thermally fused effect of thermofusing yarns, thus allegedly restraining the wrist-edge stitches from disintegrating themselves.
Nevertheless, as mentioned above, when knitting conventional gloves using the above-cited yarns for preventing the wrist-edge aperture domain from disintegration, these yarns are knitted into stitches corresponding to several-round courses at the knitted terminal including those courses which are supposed to make up the wrist-edge aperture domain.
However, since the conventional knitting process is executed by feeding those yarns to all the knitting needles which are commonly available for the knitting of wrist domain as well as for retaining stitches of the wrist edge so that knitted yarns at the wrist edge domain can be prevented from disintegrating themselves. In consequence, the wrist edge domain cannot fully be fastened by applying thereon contracting effect of those yarns provided for preventing the wrist-edge aperture domain from incurring disintegration, but the wrist-edge aperture domain is apt to turn into trumpet-like shape, thus seriously degrading appearance of the knitted gloves.
To solve this problem, conventionally, on the way of knitting the wrist-edge aperture domain, rubber yarns available for fastening the wrist-edge aperture domain are tacked on those courses respectively being composed of those yarns for preventing the wrist-edge yarns from disintegration in order to strengthen the fastening force of the wrist-edge aperture domain.
This method certainly generates such force enough to fasten the wrist-edge aperture domain. On the other hand, this method in turn causes specific problems to arise.
Concretely, since the wrist-edge aperture domain is jointly knitted with rubber yarns, rubber yarns is apt to visibly show up from the wrist-edge aperture domain to adversely affect the appearance of the knitted gloves.
Furthermore, consumable amount of rubber yarns adds up the production cost. In addition, execution of those conventional methods cited above also causes a variety of problems to arise. These problems are described below.
Using all the knitting needles available for the knitting of wrist domains, the conventional method knits the wrist-edge aperture domain by following identical plain knitting processes, and therefore, the final-course loop of the edge domain is unavoidably positioned at the wrist-edge aperture domain. When a consumer tries to put the knitted gloves on, his fingers may easily be caught by the final-course loop, and as a result, despite the preventive measure, looped yarns are easily disintegrated from each other. Furthermore, presence of the final-loop yarns causes the wearer to feel uncomfortable because the looped yarns directly come into contact with the wearer's wrist skin.
SUMMARY OF THE INVENTION
The object of the invention is to fully solve those problems described above by providing a novel method of preventing those looped yarns jointly making up a wrist-edge aperture domain from disintegrating themselves on the way of the glove knitting process and novel gloves which are properly knitted by executing the method embodied by the invention.
To securely achieve the above objects, the method embodied by the invention characteristically executes those novel processes described below.
Using a flat knitting machine, when knitting those stitches corresponding to several-round courses at the knitted terminal including those courses which are supposed to make up a wrist-edge aperture domain, the method embodied by the invention executes a knitting process so that the wrist-edge aperture domain can be turned into a pouched tubular shape, wherein at least one round course on the top edge of the pouched tubular domain is knitted by means of thermofusing yarns which are capable of preventing the wrist-edge yarns from disintegrating from each other, followed by a process for disengaging knitted gloves from the knitting machine before eventually treating the disengaged gloves with a heating process to thermally fuse those disintegration preventive yarns so that those yarns positioned at the edge of the knitted fabric can securely be prevented from disintegrating from each other.
As another characteristic aspect of the invention, on the way of knitting up stitches corresponding to several-round courses including those courses which are supposed to make up a wrist-edge aperture domain while the glove knitting process is underway, using those yarns available for preventing knit-component yarns from disintegrating themselves, a process for knitting those several-round courses is executed in succession to the preceding process for knitting a wrist domain. At the same time, part of those knitting needles are jointly rested in position by disengaging loops from following up the process for knitting the wrist-edge aperture domain to make up several rounds of courses by operating the remaining needles, and then, those needles at rest are brought back to operating condition before jointly encircling the top-edge loop with the bottom-edge loop of the wrist-edge domain so that the pouched tubular form of the wrist-edge aperture domain can properly be shaped up. To execute this method, those yarns available for preventing the knit-component yarns from disintegrating from each other may be of the composition described below. Using thermally contractile core-forming elastic yarns, those yarns free of thermal fusibility and thermal hardening property are jointly encircled to cover the core-forming elastic yarns, and yet, thermally fusible yarns may be provided on the external circumference of these yarns covering the core-forming elastic yarns in the direction opposite from each other.
The gloves knitted by operating a flat knitting machine and as per the method embodied by the invention featuring the composition described below. Using elastic yarns, pouched tubular stitches corresponding to several-round courses including those courses which are supposed to make up a wrist-edge aperture domain are provided, and in addition, stitch a of the course in succession to those several-round-course stitches are formed by means of those disintegration preventive yarns, where those stitches following those of the several-round courses are thermally fused, thus securely achieving the aimed prevention of the final stitch from incurring disintegration of knitted yarns.
Concretely, when engaging part of the knitting needles with loops, stitches corresponding to several-round courses including those courses which are supposed to make up a wrist-edge aperture domain on the way of knitting gloves are retained at a rest position, and then, using the remaining needles and in succession to the wrist domain, several-round courses of the wrist-edge aperture domain are knitted by means of those elastic yarns or the disintegration preventive yarns.
In consequence, since those stitches of the wrist-edge aperture domain are disposed in the tensional condition relative to the stitch of an adjoining course, these stitches respectively function themselves in the direction to fully strengthen a force to fasten the wrist-edge aperture domain. At the same time, in order to bring those needles at rest back to operating condition to resume the knitting operation, the top edge of the knitted fabric corresponding to the wrist-edge aperture domain bends backwards before eventually being knitted together with the other base edge of the knitted fabric, thus completing formation of a pouched tubular knitted fabric. Finally, the knitted gloves are thermally treated to secure a substantial force to restrain unwanted disintegration of edge-stitch component yarns at the wrist-edge aperture domain by virtue of the thermally fused effect of the disintegration preventive yarns.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is the schematic front view of the glove knitted by executing the method embodied by the invention;
FIG. 2 is the chart schematically illustrating the composition of the knitted fabric according to the first embodiment of the invention;
FIG. 3 is the chart schematically illustrating the composition of the knitted fabric according to the second embodiment of the invention;
FIG. 4 is the chart schematically illustrating the composition of the knitted fabric according to the third embodiment of the invention;
FIG. 5 is the sectional view of the glove shown in FIG. 1 taken on line V through V; and
FIG. 6 is the enlarged view of the domain VI shown in FIG. 5.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now more particularly to the accompanying drawings, a detailed structure of gloves and the method of manufacturing them embodied by the invention are described below. To execute the method embodied by the invention, as shown in FIG. 1 and like the conventional practice, each glove 10 is sequentially knitted in order of the little finger 1, third finger 2, middle finger 3, forefinger 4, the four-finger body 5, thumb 6, the five-finger body 7, wrist domain 8, and finally the shaped wrist-edge aperture domain 9. However, characteristically, the invention embodies the novel gloves 10 and the novel method of knitting these gloves 10 by properly knitting those stitches corresponding to several rounds of courses including those which are supposed to make up the wrist-edge aperture domain 9 by way of materializing the first through third embodiments.
The First Embodiment
As shown in FIG. 2, initially, the method embodied by the invention knits those glove components up to the five-finger body (not shown) by means of knitting yarns 100, and then knits the wrist domain 8 with the knitting yarns 100 and rubber yarns 101. Next, in place of those knitting yarns 100 and the rubber yarns 101, the method embodied by the invention knits up the wrist-edge aperture domain 9 by means of thermally fusible disintegration preventive yarns 102.
Although not being illustrated, those disintegration preventive yarns 102 available for the knitting of the wrist-edge aperture domain 9 are substantially composed of thermally fusible yarns or those yarns consisting of a core yarn encircled with thermally fusible yarns.
When the initial knitting course A is entered by applying the disintegration preventive yarns 102, the knitting operation is executed by activating all the knitting needles N1 through Nn which are made available for knitting the wrist domain 8.
Next, when the following second and third knitting courses B and C are respectively entered, of those needles activated for executing the initial knitting course A, those needles including N1, N3, N5, N7, and Nn-1, are respectively laid off from operation. On the other hand, those remaining needles including N2, N4, N6, and Nn, are respectively activated to execute the second and third knitting courses B and C.
When the following fourth knitting course D is entered, those needles including N1, N3, N5, N7, and Nn-1 thus far laid off from operation are respectively brought back to operating condition, and simultaneously, those disintegration preventive yarns 102 are delivered to all the operating needles N1 through Nn to follow the knitting operation.
Next, the bottom-edge loops of those odd needles N1, N3, N5, N7, and Nn-1, are jointly knitted in conjunction with the top loops of those even needles N2, N4, N6, and Nn thus far made available for the second and third knitting courses B and C on the way of processing the fourth knitting course D, and then, a pouched tubular knit cloth is eventually formed.
Next, the knitted gloves 10 are disengaged from the knitting machine, and then the gloves 10 are thermally treated by use of a hot iron or any other heating means. In consequence, the twisted domains of the disintegration preventive yarns are thermally fused together to effectuate prevention of those yarns around the wrist-edge aperture domain from incurring disintegration and retention of the force to prevent disintegration from occurrence, thus securely preventing the stitches around the wrist-edge aperture domain from expanding themselves into a trumpet-like configuration.
The Second Embodiment
As shown in FIG. 3, initially, the method embodied by the invention knits those glove components up to the five-finger body (not shown) by means of knitting yarns 100, followed by the knitting of the wrist-domain 8 with the knitting yarns 100 and rubber yarns 101. Next, instead of using the knitting yarns 100 and the rubber yarns 101, the method embodied by the invention knits the wrist-edge aperture domain 9 in the initial knitting course A by applying thermally fusible disintegration preventive yarns 102.
When the following second and third knitting courses B and C are activated, of those knitting needles N1 through Nn made available for the knitting of the wrist domain 8, those odd needles N1, N3, N5, N7, and Nn-1, are respectively laid off from operation. Instead, elastic yarns 103 are delivered to those remaining even needles N2, N4, N6, and Nn to follow execution of the glove knitting operation.
When the following fourth knitting course D is activated, instead of using the elastic yarns 103 made available for executing the second and third knitting courses B and C, those odd needles including N1, N3, N5, N7, and Nn-1 thus far being laid off from operation are respectively brought back to operating condition, and simultaneously, those disintegration preventive yarns are delivered to all the operating needles N1 through Nn to follow up execution of the glove knitting operation.
Next, those loops of the odd knitting needles N1, N3, N5, N7, and Nn-1 laid off from operation in the second and third knitting courses B and C are jointly knitted together with those loops of the even knitting needles N2, N4, N6, and Nn made available for processing the second and third knitting courses B and C, thus eventually forming a pouched tubular knit cloth.
Next, the knitted gloves are disengaged from the knitting machine and then subject to a thermal treatment. As a result, the encircled domains of the disintegration preventive yarns are thermally fused together to effectuate prevention of those yarns around the wrist-edge aperture domain from incurring disintegration and retention of the force to prevent them from disintegrating themselves, thus securely preventing the wrist-edge aperture domain from expanding itself into a trumpet-like configuration.
The Third Embodiment
As shown in FIG. 4, initially, the method embodied by the invention knits those glove components up to the five-finger body (not shown) by means of those knitting yarns 100, and then knits the wrist domain 8 with those knitting yarns 100 and rubber yarns 101. Next, of those knitting needles N1 through Nn made available for the knitting of the wrist domain 8 in the first and second knitting courses A and B on the way of knitting the wrist-edge aperture domain 9, those odd needles N1, N3, N5, N7, and Nn-1, are respectively laid off from operation. Next, instead of using those yarns 100 and rubber yarns 101 made available for the knitting of the wrist domain 8, elastic yarns 103 are delivered to the remaining even needles N2, N4, N6, and Nn to follow up execution of the glove knitting operation.
When the third and fourth knitting courses C and D are respectively activated, those odd needles N1, N3, N5, N7, and Nn-1 thus far being laid off in the preceding knitting courses A and B are brought back to operating condition, and simultaneously, in place of those elastic yarns 103, those thermally fusible disintegration preventive yarns 102 are delivered to all the operating needles N1 through Nn to follow up the execution of the glove knitting operation. Finally, the knitted gloves are disengaged from the knitting machine to complete the whole knitting processes.
The knitted gloves are thus disengaged from the knitting machine and then subjected to a thermal treatment. As a result, those domains of the knitting yarns 100 in contact with the disintegration preventive yarns 102 are thermally fused with those yarns 102 to effectuate prevention of those yarns around the wrist-edge aperture domain 9 from incurring unwanted disintegration and also retention of the disintegration preventive force, thus securely preventing the wrist-edge aperture domain 9 of the knitted glove 10 from expanding itself into a trumpet-like configuration.
FIGS. 5 and 6 respectively illustrate the shape of the wrist-edge aperture domain 9 of the knitted glove 10 after being knitted and thermally treated by executing the method embodied by the invention.
Concretely, by executing a knitting operation in succession to the reactivation of those needles thus far being laid off, the top edge of the knitted cloth corresponding to the wrist-edge aperture domain 9 bends backward before jointly being twisted with the base edge of the identical knit cloth. In consequence, by virtue of the thermally fused effect of the disintegration preventive yarns 102, the configuration of the punched tubular knit is securely preserved.
Those embodiments described above respectively present ideal application of the art embodied by the invention, in which the process for knitting the wrist-edge aperture domain is completed by processing four-round courses. Nevertheless, as a matter of course, the number of knitting course may optionally be variable.
For example, the first embodiment may also be executed by practically making the pouched tubular knit to be more voluminous by slightly increasing the composition of the second knitting course knitted by applying those disintegration preventive yarns 102. Furthermore, variation of the above embodiments may also be materialized by executing those processes described below. After combining the base edge of the pouched tubular knit with the top edge thereof by additionally providing the knitting course with the disintegration preventive yarns 102, stitches formed by these yarns 102 are disposed in continual courses after completing the knitting of the final round course, and then strengthen the effect of preventing the stitch of the final-round course from being disintegrated by strengthening the thermal fusing effect while executing a thermal treatment.
This variational method may be executed in the event that neither fusion nor adhesion of the disintegration preventive yarns 102 is fully materialized during the thermal treatment and then results in the failure to securely prevent the stitch of the final-round course from disintegration caused by the kind of the knitting yarns 101 or the elastic yarns 104 after completing formation of stitches of continual courses by combining those knitting yarns 100 with the disintegration preventive yarns 103 or combining the elastic yarns 104 with the disintegration preventive yarns 103.
The above embodiments have respectively provided 1:1 of the even ratio between those laid-off needles and those needles activated during the glove knitting process using those elastic yarns containing the disintegration preventive yarns. Nevertheless, it is also practical for the invention to properly adjust the force to fasten the wrist-edge aperture domain by varying the above ratio into either 1:2 or 2:2 within the scope that does not deviate from the fundamental points of the invention.
It is needless to say, especially in the third embodiment, that disintegration preventive yarns used in the present invention may be core-forming elastic yarns encircled with thermal fusible yarns, or core-forming elastic yarns encircled with yarn free of thermal fusibility and thermal curable properties and superposedly encircled with thermally fusible yarns so that the encircling yarns are in a direction opposite from each other. | A method for knitting gloves and a glove so knitted by a flat knitting machine which includes forming stitches of several circumferential courses of the knitted material which make up the wrist edge aperture domain. The method uses a knitting process in which the wrist-edge aperture domain of the glove can be turned into a pouched tubular shape in which at least one course on the top edge of the pouched tubular domain is knitted by means of a thermofusing yarn and then thermally fused. | 3 |
BACKGROUND OF THE INVENTION
The most prevalent fault in golfers is the slice swing wherein the golf club head connects with the ball in a manner that the toe of the club head is behind the base of the head so that the ball is not hit squarely but by the face of the golf club in a plane angled to the right, thus causing the ball to spin and veer off to the right. There are several aspects to a good golf swing. The release is that aspect of the swing which relates to the hitting area and part of the release motion is the release crossover where both forearms rotate causing the right palm to be almost facing the ground at a point halfway into the through swing or follow through. It is preferable to allow the arms to swing extended until reaching the reset position which is approximately waist high on the through swing and, at that point, the hands start to reset or rehinge to the follow through position. This reset does not occur in the slice swing because the left arm collapses instead of rotating and the right hand goes through palm up instead of palm down. A high follow through is desirable and keeps the swing on plane longer, carrying the hands to a high finish.
In an attempt to correct the slice swing, it has been proposed to attach a small flat airfoil to the shaft of a golf club, as disclosed in U.S. Pat. No. 4,576,378. While this training device has been somewhat satisfactory for its intended purpose, the training attachment of the present invention is an improvement thereon.
SUMMARY OF THE INVENTION
The training airfoil attachment of the present invention comprises, essentially, a member curved in cross-section and having a convex upper surface and a concave lower surface and substantially straight leading and trailing edges. The trailing edge of the airfoil is connected to the shaft of a golf club thereby promoting the correct swing due to the airflow over the airfoil imparting a lift on the convex side of the airfoil in the same way as an aircraft wing is lifted by the air flowing from the leading edge over the longer or convex edge. The lift imparted to the airfoil is further enhanced when the golf club and associated attachment is swung into the wind. This lift effect is not provided by the flat plate airfoil disclosed in U.S. Pat. No. 4,576,378 which provides more wind resistance than lift effect.
In the instant invention, resistance is felt only if the club is swung incorrectly; in which case, as the club is swung down, the golfer will hear a swooshing sound before the hitting area is reached, indicating that the face of the club is closed due to an incorrect grip or hand position, or the golfer has started his release too early. The sound caused by the airfoil thereby alerts the golfer to an incorrect swing.
The airfoil of the present invention is dimensioned to be larger and therefore more visual than the airfoil in the aforementioned patent to thereby provide a visual aid so that the golfer viewing his or her reflection in a window or mirror can visually check the appearance of the airfoil in relation to the club in a good swing.
The training airfoil attachment of the present invention can be fabricated from various materials such as wood or plastic, either injection molded to shape or formed from sheet, or various metals and alloys such as aluminum or other easily workable or castable metal or composite materials.
The airfoil can be integrally formed with the shaft of the golf club or can be detachably connected to the shaft by clamps or quick-release fasteners.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the training airfoil attachment of the present invention connected to the shaft of a golf club gripped by a golfer and shown in various positions along a golf swing;
FIG. 2 is a cross-sectional view of the airfoil of the present invention fabricated from plastic;
FIG. 3 is a cross-sectional view of the airfoil fabricated from metal;
FIG. 4 is a cross-sectional view of the airfoil fabricated from wood;
FIG. 5 is a side elevational view of the airfoil of the present invention secured to the shaft of a golf club by a pair of clamps and extending substantially the length of the shaft;
FIG. 6 is a view taken along line 6--6 of FIG. 5;
FIG. 7 is a perspective view of another embodiment of a clamp for securing the airfoil of the present invention to the shaft of a golf club;
FIG. 8 is a cross-sectional view of the airfoil of the present invention formed integral with the shaft of a golf club;
FIG. 9 is a side elevational view of the airfoil of the present invention secured to the shaft of a golf club and having a linear dimension substantially less than the airfoil shown in FIG. 5; and
FIG. 10 is an enlarged, fragmentary, side elevational view of an airfoil and shaft of a golf club having cooperating components of a side squeeze snap fastener for detachably connecting the airfoil to the shaft.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the drawings and more particularly to FIGS. 1 and 5, the training airfoil attachment 1 of the present invention is connected to the shaft 2 of a conventional golf club 3 and extends substantially along the length of the club shaft 2.
As will be seen in FIGS. 2, 3 and 4, the airfoil 1 is formed as a thin curved member having a convex upper surface 4 and a concave lower surface 5, and can be fabricated from plastic, metal or wood, as shown. As will be seen in FIG. 5, the airfoil 1 is secured to the golf club shaft 2 by a pair of clamps 6 axially spaced on the shaft 2 and secured to the trailing edge portion 7 of the airfoil 1 by a nut and bolt assembly 8; and in order that the bottom edge of the airfoil 1 will clear the ground during the golfer's swing, it is cut-away as at 9.
While FIG. 5 discloses a pair of separate clamps 6 for securing the airfoil 1 to the golf club shaft 2, FIG. 7 shows another embodiment for securing the airfoil to the golf shaft wherein three clevis-type clamps 10, of the type shown in FIGS. 5 and 6, are integral with a spine member 11 which would extend along the golf club shaft.
FIG. 8 illustrates another embodiment of securing the airfoil 1 to the golf club shaft 2 wherein the airfoil is formed integral with the shaft.
While the airfoil 1 as shown in FIG. 5 is dimensioned to extend substantially along the entire length of the golf club shaft 2, FIG. 9 shows an airfoil 12 having a length substantially less than the length of the golf club shaft 2, whereby the position of the airfoil 12 can be adjusted along the length of the golf club shaft 2 so that more drag would be imparted to the golf club 3 when the airfoil 12 is positioned at the lower end of the shaft 2, and less drag when the airfoil 12 is positioned toward the upper portion of the shaft.
FIG. 10 illustrates still another manner of securing the airfoil 1 to the golf club shaft 2 by conventional side squeeze snap fasteners 13 wherein one component 14 of each fastener is secured to the club shaft as at 15 and the other component 16 of the fastener is secured to the airfoil as at 17.
The airfoil 1 is dimensioned to have a length of 22 inches by 8 inches by one-sixteenth of an inch in thickness and a weight of approximately 7 ounces, while airfoil 12 is dimensioned to have a length approximately 15 inches, and while the airfoil is shown connected to the shaft of an iron, it can also be connected to the shaft of a wood.
From the above description, it will be appreciated by those skilled in the art that the training airfoil golf club attachment of the present invention is constructed and arranged to improve the swing of a golfer and helps to eliminate the slice which is a recurring problem with many golfers. A further benefit of the attachment is that it increases hand speed and improves release in the hitting area, plus it encourages the rotation of both fore arms causing the right palm to be almost facing the ground at a point halfway into the through swing or follow through, thereby promoting a high follow through. By attaching the airfoil 1 to the golf club 3 as described hereinabove, as the club approaches the ball, the airflow over the airfoil causes the club head to close to the left thereby promoting the hook swing. This gives the golfer "the feel" of a good swing and as the golfer becomes familiar with the differences between a good and a bad swing, as is forced upon the golfer by the airfoil attachment, the golfer can ultimately detach the airfoil and continue with the same style of swing to achieve a faster club head speed, greater distance and more accuracy.
It is to be understood that the forms of the invention herewith shown and described are to be taken as preferred examples of the same, and that various changes in the shape, size and arrangement of parts may be resorted to, without departing from the spirit of the invention or scope of the subjoined claims. | A training airfoil attachment for a golf club wherein a member curved in cross-section and having a convex upper surface and a concave lower surface, and substantially straight leading and trailing edges, is attached to the shaft of the golf club to promote the correct swing due to the airflow over the airfoil imparting a lift on the convex side of the airfoil. | 0 |
FIELD OF THE INVENTION
[0001] The present invention relates generally to hand tools that can be used in fabrication of structures from metal tubes and beams, and is more particularly directed to a framing tool, namely a squaring tool, that can be easily used for measuring and marking tubular beams, i.e., beams of generally square or rectangular cross section, but which may have rounded or radiused edges.
BACKGROUND OF THE INVENTION
[0002] Steel beams are widely employed in the construction of many types of structures, and in particular tube beams, i.e., rectangular section pipes, are employed in many situations. These tube beams need to be cut and welded in the construction process.
[0003] Steel beams, including tube beams, need to be measured and scored or marked for cutting and welding. A problem arises from the presence of the radiused corners or edges of the pipe. Typically, the welder working with this type of pipe has to use a squaring tool to measure the places along the pipe where a cut or weld is to be positioned. However, a standard, i.e., flat framing square, is difficult to use at the front or open edge of the tube beam, partly owing to the curved corners of the beam. It is difficult or impossible to place the second arm or blade of a flat framing square against a flat side of the tube beam when measuring and marking the front edge of another flat side of the tube beam, and typically the welder will have to tilt the tool to attempt to position the second blade against the side of the tube beam. However, this can lead to inaccuracies in marking the beam.
[0004] It is this difficulty to which the present invention is addressed.
OBJECTS AND SUMMARY OF THE INVENTION
[0005] Accordingly, is an object of the present invention to provide a framing tool that can be used with tubular beams and which overcomes the drawbacks of the prior art. It is a further object of the present invention to provide a framing tool of a straightforward design which is simple for the welder or other workman to use.
[0006] It is another object to provide a tool which can be employed in a number of different applications for speedy and accurate framing and marking of workpieces.
[0007] In accordance with an aspect of this invention a squaring tool is provided in which there are two blades directed at ninety degrees from one another, but there is an offset at the proximal ends where the blades are connected. This permits one blade to be positioned at the front edge of a top side or flange of the tube beam, with the other blade placed directly against a web or side wall of the beam but at a position a short distance away from the edge. The framing square is thus positioned square to the beam, and can be used for quickly and accurately marking a position on the top flange (or any other side of the beam), both at the edge and at other positions along the beam.
[0008] More specifically, a squaring tool is adapted for measuring exterior planar surfaces of a workpiece wherein said exterior planar surfaces are at substantially a right angle to one another and meet at a rounded or radiused edge. A first planar blade of the tool extends in a first direction in a first plane from a proximal end to a distal end of the blade, and has inside and outside parallel edges extend in that first direction. A second planar blade extends in a second direction, perpendicular to said first direction. The second blade is located in a second plane that is parallel to the first plane (the plane of the first blade) but offset from it by a predetermined offset distance. The second blade also has inside and outside parallel edges that extend in the second direction. An offset member joins the proximal end of the first blade with the proximal end of the second blade. This framing tool is constructed with inside edges of the first and second blades being free of any protuberance or obstruction. Consequently, each of said inside edges can lie flat against a respective exterior planar surface of the workpiece, and the blades themselves can also lay flat against a flat surface of the workpiece.
[0009] In preferred embodiments, the offset member extends at a first predetermined angle from the proximal end of the first blade and is joined to the proximal end of said second blade at a second angle complementary to said first angle, such that the two blades lie in parallel planes. The first and second angles may both be substantially 90 degrees, or the first and second angles may be substantially 45 and 135 degrees, respectively. each of said blades has gradations at predetermined intervals along the inside edges thereof.
[0010] Favorably, the offset member connects to the inside edge of said first blade at the proximal end thereof, and to a proximal edge of the second blade.
[0011] Each of the blades may have gradations at predetermined intervals along the inside edges thereof, or preferably on both the inside and outside edges. These may be in inch-based intervals or centimeter based intervals, or both.
[0012] The framing tool may be formed unitarily of steel, although an aluminum alloy, a tough plastic, or another sturdy material may be used for it, as appropriate.
[0013] The above and many other objects, features, and advantages of the invention will become apparent from the accompanying Drawing figures, which are to be considered in connection with the following description.
BRIEF DESCRIPTION OF THE DRAWING
[0014] FIG. 1 is a perspective view of a framing square according to an embodiment of this invention.
[0015] FIG. 2 is another perspective view illustrating an alternative embodiment of the present invention.
[0016] FIG. 3 is perspective view illustrating the use of the tool of the present invention with a tubular beam.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] With reference to FIGS. 1 to 3 of the Drawing, and initially to FIG. 1 , there is shown a framing square 10 there formed of a first blade 12 and a second blade 14 that extend at right angles from one another. Each of the blades 12 and 14 has two parallel edges, and has a proximal end ( 12 - 1 and 14 - 1 , respectively) at the corner formed by the two blades, and each has a proximal or free end ( 12 - 2 and 14 - 2 , respectively). The two blades 14 and 16 lie in parallel planes that are spaced apart from one another. An offset 16 joins the proximal ends of the two blades, and here the offset 16 meets the side of the first blade proximal end 12 - 1 at ninety degrees and also joins the end of the second blade proximal end 14 - 1 at ninety degrees. The offset 16 extends about one to two inches, although the exact length of the offset is not critical.
[0018] FIG. 2 shows a second embodiment in which the framing square 110 has a first blade 112 and a second blade 114 that extend out in directions that are at right angles to one another, and the blades 112 and 114 lie in parallel planes that spaced an offset amount from one another. Here an offset 116 joins the proximal ends of the two blades, but at angles of forty-five degrees and one-hundred thirty-five degrees, i.e., bent down 45 degrees and then bent up 45 degrees. In other embodiments, the offset can be angled at any two angles that are complementary to one another, and will result in the two blades lying parallel to one another.
[0019] In each embodiment, the blades have markings or gradations spaced along at least the inside edge, and favorably on both edges and both sides of the blades. These can be in intervals of inches and fractions of an inch, or in International units (centimeters and millimeters). Most favorably, the framing square 10 or 110 is formed of a single piece of steel sheet, but can be formed of another suitable material, e.g., a sturdy aluminum alloy or any of a variety of modern synthetic plastic resins.
[0020] The method of employing the squaring tool of this invention is illustrated in FIG. 3 . In this application, the framing tool 10 is used for measuring and marking a steel tubular beam 20 , in which adjacent web or flange surfaces 22 and 24 are flat and at right angles to one another, but are joined at a rounded or radiused edge 26 . In this application, the first blade 12 can be laid along the beam 20 on web surface 22 , and the second blade 14 is a short distance below that with its edge along flange surface 24 . The flat of the blade 12 and the edge of the blade 14 are placed flush against the respective surfaces 22 and 24 , and with the blade 12 square to the beam axis. This allows the beam to be marked accurately, using the blade or blades as a guide, to mark the workpiece for cutting or welding at specific locations along the web surface from the front edge to similar locations along the beam and spaced back from the front edge, along the web surface 22 . The tool 10 can be held square to the beam because the end 12 - 1 of the first blade and the offset 12 joining to the proximal end 14 - 1 of second blade 14 bridge around the curved or radiused edge 26 , by virtue of the offset 16 . This is not possible with a standard, single-plane framing square. The offset 16 or 116 avoids having to lie the tool onto the rounded or radiused edge 26 . The second blade 14 or 114 is placed axially along the beam 20 , i.e., parallel the web surface 22 and also parallel to the edge 26 , and does not have to be angled back on the tubular beam.
[0021] Also the inside edges of the two blades are flat and straight, and free of any protuberances or obstructions, so that they can both contact the flat surfaces of the tubular beam 20 flush against the respective surface of the beam.
[0022] In the illustrated embodiments, the shorter, second blade 14 or 114 is shown offset from the right-hand side of the first blade 12 or 112 , but the tool could be fabricated with the second blade offset from the left-hand side of the first blade.
[0023] This framing tool may also be employed favorably when working with other beam types that have a flange and web joined at a rounded edge, e.g., an L-profile beam or a C-profile channel beam.
[0024] Many modifications and variations are possible, in addition to the above-described preferred embodiments of the invention, without departing from the scope and spirit of the present invention, as defined in the appended claims. | A framing tool, namely framing square, is provided with an offset at the proximal ends of the two blades, so that the blades lie in parallel planes. This tool facilitates measuring and marking tubular beams, i.e., beams of generally square or rectangular cross section, but which may have rounded or radiused edges. | 6 |
BACKGROUND OF THE INVENTION
[0001] The present invention relates generally to locking and security devices, and particularly to a locking and security device for preventing theft of portable computers.
[0002] Portable computers by their nature are used in a variety of locations. Most typically, a portable computer user sets up a temporary work site and makes use of the portable computer. For example, the user may sit in a library or cafe at a table and chair and set up a portable computer. Unfortunately, the user often finds need to move from the temporary work site for brief times. For example, to visit a restroom, purchase a beverage, or retrieve reference items in a library. Given the portable and compact nature of such valuable computing devices, leaving such a device unattended for even the briefest time presents significant risk of theft. Nevertheless, some portable computer users will risk such theft due to the inconvenience of carrying with them at all times their portable computing device.
[0003] Once the portable computing device is set up at a selected temporary work site, some portable computer users tend to leave the portable computer in place even while leaving the work site for brief times. Other users may take the time and trouble to break down their temporary work site and carry with them their portable computing device to avoid any risk of theft. Preferably, however, portable computer users have a mechanism for securing their portable computing device against theft even while unattended at a temporary work site. Accordingly, a variety of devices have evolved with the general purpose of protecting against or impeding theft while unattended at a temporary work site. common security device for portable computers is known as a Kensington lock. Generally, the Kensington lock is a cable having at one end a preformed small loop formation and at the other end a lug attachable to a preformed mounting site on the portable computer. In use, the cable attaches to an object by passing the lug portion around the object and through the small preformed loop at the distal end of the cable. This forms a loop about the object and leaves the lug element available for attachment to the computer. The preformed mounting site on the computer lockably receives the lug and thereby secures the portable computer to the larger object. The preformed loop provided at the distal end of the cable need only be large enough to allow passage of the lug therethrough. The relatively larger loop formation created at the distal end of the cable, i.e., a length portion of the cable adjacent the preformed loop and passing through the preformed loop, remains coupled to the object so long as the lug remains attached to the portable computer and so long as the preformed loop is smaller than the computer itself.
[0004] It would be preferable, however, to provide a portable computer security device more conveniently carried with the portable computing device and used to prevent or impede theft thereof.
SUMMARY OF THE INVENTION
[0005] A security device under the present invention as applied to a portable computer includes an anchor attached securely to the portable computer. A lockbox includes an open ended channel having a lateral or side wall selectively openable and lockably closed. A cord couples the anchor and the lock box. The cord attaches to an immobile or relatively immobile object by passing the lock box around the object and opening the channel to laterally receive and capture the cord therein. This creates a selectively lockable loop formation about the object and secures the portable computer to the object.
[0006] The subject matter of the present invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. However, both the organization and method of operation of the invention, together with further and objects thereof, may best be understood by reference to the following description taken with the accompanying drawings wherein like reference characters refer to like elements.
BRIEF DESCRIPTION OF THE DRAWINGS
[0007] For a better understanding of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings in which:
[0008] [0008]FIG. 1 illustrates a first embodiment of the present invention, a portable computer security device coupling in secure fashion a portable computer to, for example, a chair.
[0009] [0009]FIG. 2 illustrates a lock box of the security device of FIG. 1 and loop structure formed thereby.
[0010] [0010]FIG. 3 illustrates the lock box of FIG. 2 as taken along lines 3 - 3 of FIG. 2 and showing the lock box of FIG. 2 in its open or unlocked condition.
[0011] [0011]FIG. 4 illustrates the lock box of FIG. 2 as taken along lines 3 - 3 of FIG. 2 but illustrating the lock box in its closed or locked condition.
[0012] [0012]FIG. 5 illustrates a second embodiment of the present invention including a retractable form of portable computer security device.
[0013] [0013]FIG. 6 illustrates operation of the retractable security device of FIG. 5 including a variable length cord extending between a lock box and anchor thereof.
[0014] [0014]FIG. 7 illustrates in more detail the loop structure feature of the lock box of FIG. 5 FIG. 8 illustrates retraction of a cord portion of the security device of FIG. 5.
[0015] [0015]FIG. 9 illustrates the retractable security device of FIG. 5 prior to forming a loop structure and as anchored to a portable computer.
[0016] [0016]FIG. 10 illustrates the retractable security device of FIG. 5 as coupled to a relatively larger object.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0017] [0017]FIG. 1 illustrates the use of a portable computer security device 10 according to the first embodiment of present invention as applied to a notebook computer 12 to secure notebook computer 12 relative to an object, e.g., chair 14 . Security device 10 includes an anchor 20 securely attached to computer 12 , a cord 22 extending therefrom, and a loop-forming lock box 24 at a distal end of cord 22 . As discussed more fully hereafter, loop-forming lock box 24 creates a loop structure 26 at the distal end of cord 22 . By forming loop structure 26 about a relatively larger object, e.g., chair 14 , security device 10 prevents, or at least hinders, the unauthorized taking of computer 12 without also taking chair 14 . As may be appreciated, loop structure 26 may be coupled to a variety of objects, such as chair 14 , including relatively immobile objects, e.g., a table leg, building post, building pillar, or other such structures which may be captured within loop structure 26 according to an embodiment of the present invention.
[0018] As used herein, reference to chair 14 , or other relatively immobile object, refers to a structure selected by the user for attaching to the portable computer by way of the security device that accords with the present invention. Thus, chair 14 , or other selected object may be in fact immovable or merely a relatively larger object that significantly impedes the theft of a portable computer attached thereto.
[0019] Anchor 20 securely attaches to the body of computer 12 according to a variety of methods and structures. For example, anchor 20 can be coupled to computer 12 by way of a sufficiently durable and strong adhesive. In such configuration, security device 10 may be coupled, i.e., retrofit, to any portable computing device. Alternatively, anchor 20 may be mechanically and selectively lockably coupled to a preformed structure on a given portable computer 12 . In such case, anchor 20 selectively detaches from the portable computer 12 , but securely attaches when security device 10 is in use. Finally, anchor 20 may be integrally formed at a time during the manufacture of portable computer 12 , thus being permanently integrated therewith. In any case, anchor 20 should be sufficiently secured to computer 12 to avoid detachment therefrom. In a preferred form of the present invention, anchor 20 permanently attaches to the device to be secured, e.g., to computer 12 .
[0020] [0020]FIG. 2 illustrates in more detail the distal end of cord 22 including loop structure 26 as established by use of lock box 24 . As illustrated in FIG. 2 lock box 24 is shown in its locked condition including cord channel 28 in which a length portion of cord 22 resides. As described more fully hereafter, lock box 24 includes, along a lateral wall of channel 28 , a tongue 30 . Tongue 30 laterally opens channel 28 when lock box 24 is opened, i.e., taken out of its locked condition. Thus, loop structure 26 forms by opening channel 28 , i.e., moving tongue 30 out of its closed position, thereafter positioning a length portion of cord 22 within channel 28 . Once cord 22 is so positioned, tongue 30 moves into its closed position to capture cord 22 within channel 28 . As may be appreciated, cord 22 cannot be moved laterally from channel 28 when in its locked position, but does enjoy longitudinal freedom of movement along channel 28 . Thus, loop structure 26 assumes a variety of sizes by sliding cord 22 within channel 28 . Thus, loop formation 26 suitably surrounds objects, such as chair 14 , which may be of varying size.
[0021] To capture an object 14 within a loop structure 26 , one begins with cord 22 outside channel 28 . Lock box 24 moves about an object and comes into position adjacent a length portion of cord 22 . Channel 28 opens, i.e., tongue 30 moves to its open position, to allow a length portion of cord 22 to enter laterally into channel 28 . Once cord 22 is positioned within channel 28 , lock box 24 locks, i.e., tongue 30 moves to its closed position, to capture cord 22 within channel 28 and to also capture an object, e.g., chair 14 , within the loop structure 26 created by lock box 24 and cord 22 .
[0022] [0022]FIGS. 3 and 4 illustrate schematically lock box 24 in its unlocked or open state (FIG. 3) and in its locked or closed state (FIG. 4). In FIG. 3, lock box 24 is shown in its open condition with channel 28 opened laterally by displacement of tongue 30 . FIG. 4 illustrates lock box 24 in its closed condition with channel 28 laterally closed by suitable placement of tongue 30 . In FIG. 3, with channel 28 laterally open, cord 22 moves laterally, as indicated at reference numeral 40 , into channel 28 . Once so positioned, i.e., as in FIG. 4, tongue 30 moves, as indicated at reference numeral 42 , to its closed position thereby laterally capturing cord 22 within channel 28 .
[0023] The particular lock mechanism used to permit lateral entry of cord 22 into channel 28 and thereafter to laterally close channel 28 may be according to a variety of structural and mechanical arrangements. In the particular arrangement of lock box 24 , i.e., according to this particular illustrated embodiment of the present invention, lock box 24 includes an inner tube 50 rotatable, under certain allowed conditions, about a central axis 52 of lock box 24 . A set of lock pins 54 couple inner tube 50 and lock box case 56 to prevent rotation of inner tube 50 about axis 52 . A key ( 58 ) suitably positioned within a central key aperture 60 moves pins 54 out of engagement relative to inner tube 50 . Thus, insertion of key 58 into aperture 60 permits rotation of inner tube 50 about central axis 52 .
[0024] It will be understood, however, that a particular locking mechanism selected for use in conjunction with the present invention may assume a variety of forms according to known locking structures and methods. The schematic illustration shown herein presents a simplified form of one candidate locking mechanism considered suitable under the present invention. Generally, lock box 24 desirably possesses a capability of laterally and lockably capturing cord 22 within an otherwise open ended channel 28 . This allows lock box 24 , when situated at the distal end of cord 22 , to approach a length portion of cord 22 laterally and lockably capture that length portion of cord 22 within its channel and thereafter block lateral escape.
[0025] An outward facing surface of inner tube 50 carries a gear set 70 . Thus, rotation of inner tube 50 moves gear set 70 relative to the remainder of lock box 24 , i.e., relative to case 56 . Tongue 30 is captured between inner tube 50 at gear set 70 and inner surface 72 of case 56 . Tongue 30 carries gear set 74 , which is matingly compatible and engaged relative to gear set 70 . Thus, rotational movement of inner tube 50 translates into thrusting movement of tongue 30 between its open (FIG. 3) and its closed positions (FIG. 4) as indicated by reference numeral 42 . In other words, rotation of inner tube 50 moves gear set 70 along a path coincident with the allowed path of tongue 30 and, by virtue of mutual engagement between gear set 70 and gear set 74 , tongue 30 moves reciprocally between its open and closed positions by reciprocal rotational movement of inner tube 50 . Because inner tube 50 moves only by use of a suitable key 58 , lock box 24 cannot be changed from its closed to open position without the use of a suitable instrument, such as key 58 . A particular embodiment of the present invention, however, need not necessarily prevent movement of tongue 30 from the closed to open position absent use of key 58 . A preferable security feature is, as may be appreciated, the prevention of movement of tongue 30 from a closed to an open position without use of an appropriate device, such as key 58 .
[0026] [0026]FIG. 5 illustrates a second embodiment of the present invention. In FIG. 5, security device 110 including retractable lock box 124 are shown. As illustrated in FIG. 5, lock box 124 is in its fully retracted position with its cord 122 (shown in FIG. 6) collected within the body of anchor 120 . Anchor 120 securely attaches to the body of a device to be secured, e.g., portable computer 112 . When not in use, cord 122 withdraws for storage within anchor 120 and lock box 124 resides adjacent anchor 120 .
[0027] Anchor 120 securely can attach to the body of computer 112 according to a variety of methods and structures. For example, anchor 120 can be coupled to computer 112 by use of sufficiently durable and strong adhesive. In such configuration, security device 10 may be coupled, i.e., retrofit, to any portable computing device. Alternatively, anchor 120 may be mechanically and selectively lockably coupled to a preformed structure on a given portable computer 112 . In such case, anchor 120 selectively detaches from the portable computer 112 , but securely attaches when security device 10 is in use. Finally, anchor 120 may be integrally formed at the time of portable computer 10 manufacture and thereby permanently integrated therewith. In any case, during use of portable computer 112 , anchor 120 should be sufficiently secured to the computer to avoid detachment therefrom. In a preferred form of the present invention, anchor 120 permanently attaches to the device it secures, e.g., permanently attaches to computer 112 .
[0028] [0028]FIG. 6 illustrates anchor 120 apart from computer 112 and illustrates lock box 124 in its fully retracted position, as indicated at referenced numeral 124 a and similar to that shown in FIG. 5. FIG. 6 also illustrates lock box 124 in its extended position, as indicated at reference numeral 124 b in FIG. 6. Cord 122 extends from the body of anchor 120 as attached to lock box 124 and collects about spool 180 (FIG. 9) within the body of anchor 120 . A hinged or pop up crank knob 182 operates to rotate spool 180 to collect, i.e., wind up, cord 122 on spool 180 .
[0029] [0029]FIG. 7 illustrates a loop formation using lock box 124 and cord 122 . Generally, lock box 124 is identical to lock box 24 and includes an open ended cord channel 128 and tongue 130 . Key 132 engages key aperture 160 of lock box 124 to selectively move tongue 130 into and out of an open and closed position. More particularly, key 132 operates to open laterally channel 128 and allow cord 122 to move laterally into channel 128 . Once cord 122 is so positioned, key 132 operates to close laterally channel 128 , i.e., move tongue 130 into its closed position, and prevent lateral escape of cord 122 from channel 128 .
[0030] As may be appreciated, lock box 124 may be extended from anchor 120 to a selected distance by merely pulling lock box 124 away from anchor 120 and thereby unspooling or unwinding cord 122 from spool 180 . Spool 180 may be rotated manually to collect, i.e., wind, cord 122 on spool 180 as illustrated in FIG. 8 by grasping knob 182 and rotating spool 180 as indicated at reference numeral 184 in FIG. 8.
[0031] Thus, lock box 124 extends a selected distance from anchor 120 as indicated in FIG. 9. Lock box 124 resides at the distal end of cord 122 and cord 122 , as extended from anchor 120 , may be at a selected distance therefrom. To secure computer 112 relative to an object 114 (of FIG. 10), one passes lock box 124 around the relatively larger object and opens channel 128 to laterally receive a length portion of cord 122 within channel 128 . Thereafter, key 132 operates to close laterally channel 128 and thereby laterally and lockably capture cord 122 within channel 128 . FIG. 10 illustrates attachment of computer 112 by way of anchor 120 , cord 122 , and lock box 124 to a chair 114 .
[0032] While illustrated as being coupled to a chair 114 , it will be understood that the present invention allows a user to couple a portable computing device to a variety of immovable and relatively immovable objects such as chair 14 . Preferably, a valuable portable computer is attached to a relatively larger object and thereby requires that a thief also carry away the relatively immobile object in addition to the computer. Thus, a thief would be discouraged from theft due to the inability to conceal the relatively larger object. In other words, while it may be possible to grab and hide a portable computer by itself, one cannot nearly as easily grab and conceal a relatively larger object, e.g., chair 114 , and expect to be successful in walking away unnoticed.
[0033] While not specifically detailed herein, it will be understood that cords 22 and 122 are of suitable material for the purposes shown herein. More particularly, cords 22 and 122 should be flexible enough to allow loop formation, i.e., loops 26 and 126 . Furthermore, cords 22 and 122 should be of suitable material to make impossible or significantly impede any cutting thereof. Thus, cords 22 and 122 can be of steel cable, sheathed steel cable, sufficiently durable and tamper-resistant plastic material, or other such materials as are appropriate for the given purpose of preventing or substantially impeding theft of a portable device. In other words, the degree of security desired dictates the selection of materials for cords 22 and 122 . For greater security, more durable and tamper-resistant material should be selected for use in cords 22 and 122 .
[0034] It will be appreciated that the present invention is not restricted to the particular embodiment that has been described and illustrated, and that variations may be made therein without departing from the scope of the invention as found in the appended claims and equivalents thereof. | A security device for portable computer is disclosed. The security device comprises an anchor attached securely to the portable computer. The device also includes a lock box that makes use of a channel, wherein the channel is open at each end and is selectively openable laterally. The device further includes a cord that couples the anchor and the lock box. | 8 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] None.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not Applicable.
BACKGROUND OF THE INVENTION
[0003] The present invention relates to methods, compositions, and apparatuses for the detection and prevention of chatter in doctor blades on a Yankee dryer. As described at least in U.S. Pat. Nos. 7,691,236, 7,850,823, 5,571,382, 5,187,219, 5,179,150, 5,123,152, 4,320,582, and 3,061,944, in the tissue manufacturing process, a paper sheet is dried on a heated drying cylinder, termed a Yankee or Yankee dryer. Often adhesive materials are used to coat the Yankee surface in order to help the wet sheet adhere to the dryer. This improves heat transfer, allowing more efficient drying of the sheet. Most importantly, these adhesives provide the required adhesion to give good creping of the dry sheet. Creping is the process of impacting the sheet into a hard blade (called a doctor blade), thus compressing the sheet in the machine direction, creating a folded sheet structure. Creping breaks a large number of fiber-to-fiber bonds in the sheet, imparting the qualities of bulk, stretch, absorbency, and softness which are characteristic of tissue. The amount of adhesion provided by the coating adhesive plays a significant role in the development of these tissue properties.
[0004] In addition, the present invention covers detection and prevention of chatter in doctor blades used for cleaning residual coating from the Yankee surface as well as the cut-off doctor blade used during maintenance operations on the creping doctor blade. The present invention focuses on the creping operation, but extension of methodology to the cleaning and cut-off blade apply equally as well.
[0005] The Yankee coating also serves the purpose of protecting the Yankee and creping blade surfaces from excessive wear. In this role, the coating agents provide improved runabitity of the tissue machine. As creping doctor blades wear, they must be replaced with new ones. The process of changing blades represents a significant source of tissue machine downtime, or lost production, as creped product cannot be produced when the blade is being changed. Release agents, typically hydrocarbon oils, are used in association with the coating polymers. These agents aid in the uniform release of the tissue web at the creping blades, and also lubricate and protect the blade from excessive wear.
[0006] Proper and sustained interaction between the Yankee coating and the creping doctor blade is critical for both sheet property development and machine runnability. In normal operations, the creping doctor blade tip rides in the coating on the dryer surface and experiences minimal out of plane movement. However, if the amplitude of the out of plane movement becomes high enough the creping doctor blade wilt oscillate above and below the sheet leading to the development of chatter that appears as cross directional (CD) defects. Sheet defects from chatter will appear as multiple holes in the CD or develop a lace appearance. Coating defects can exhibit long CD marks that are visible when viewed with a strobe light. Under severe chatter conditions, the doctor blade will penetrate through the Yankee coating making direct contact with the dryer surface. If this occurs, potential damage to the dryer surface with the appearance of horizontal grooves on the metal surface can result. Once the dryer surface becomes damaged, it can only be repaired by taking the machine out of production and regrinding the dryer surface. Regrinding is a costly operation, because of production losses and cost of the procedure as well as degrading the dryer service lifetime due to reduction in wall thickness that negatively affects the vessel pressure rating. Therefore, it is imperative for manufacturers to closely monitor the process and identify when chatter is present.
[0007] Excessive vibration on the creping doctor blade, leading to chatter conditions, can originate through mechanical and operational or process conditions. Examples of mechanical vibration sources include press rolls, pumps, felts, Yankee cylinder bearings, etc., as well as dryer roundness deformation caused by thermal non-uniformities. Once a mechanical vibration source is identified, maintenance intervention to correct the problem often requires shutting down the equipment resulting in production loss. Conversely, operational practices or process conditions inducing excess vibration may include sheet moisture levels, coating chemistry, machine speed, basis weight, furnish, blade stick out and loading pressure, etc. can be attended to without interrupting production.
[0008] Regardless of the source, excess vibration experienced by the doctor blade can lead to chatter conditions affecting product quality, machine runnability, and asset value. Operators will often rely on audible sound changes or visual inspection (sheet quality or Yankee dryer surface) as the first indication that chatter is present. However, this approach is subjective and not reliable often resulting in detecting chatter after the condition has become severe, thus making corrective action steps more difficult. To improve the reliability and detection sensitivity for chatter detection, condition monitoring (CM) technology using piezoelectric and/or microphone sensor(s) can be used. CM has a long history in the paper industry, but mainly for use in bearing monitoring on rotating components. Examples of using CM on the creping doctor blade is limited and in these cases measurement analysis is made following traditional CM methods based on sensor signal level exceeding an alarm limit. In this approach, the system state is assessed from the sensor signal trend. A flat trend is considered a normal condition whereas an upward sloping trend indicates a wear condition, and a step change is considered a component failure. The dynamics of the Yankee dryer operation can produce large variations in the sensor signal, without reaching a chatter condition. As a result, data analysis becomes more complex compared to conventional CM based on wear and failure detection levels.
[0009] Previous attempts to address this problem include: Aurelio Alessadrini and Piero Pagani, Chatter Marks: Origin, Evolution and Influence of the Creeping Doctors , Ind. Carta vol. 41, no. 4, June 2003, pp 120-129 , S. Archer, V. Grigoriev, G. Furman, L. Bonday, and W. Su, Chatter and Soft Tissue Production: Process Driven Mechanisms, Tissue World Americas , February-March 2009, pp 33-35, S. Zhang, J. Mathew, L. Ma, Y Sun, and A. Mathew, Statistical condition monitoring based on vibration signals , Proceedings VETOMAC-3 & ACISM-2004, pp. 1238-1243, New Delhi, India, M Fugate, H Sohn, and C. Farrar, Vibration - based damage detection using statistical process control , Mechanical Systems and Signal Processing, Vol. 15, Issue 4, July 2001, pp 707-721, H Sohn, C. Farrar, Damage diagnosis using time series analysis of vibration signals , Smart Materials and Structures, Vol 10, 2001, pp. 446-451, A. Heng, S. Zhang, A. Tan, and J. Mathew, Rotating machinery prognostics: State of the art, challenges and opportunities , Mechanical Systems and Signal Processing, 23, 2009, pp. 724-739 , A, Messaoud, C. Weihs, and F. Hering, Detection of chatter vibration in a drilling process using multivariate control charts , Computational Statistics & Data Analysis, Vol. 52, 2008, 3208-3219, A. A., Junior, F. C. Lobato de Almeida, Automatic faults diagnosis by application of neural network system and condition - based monitoring using vibration signals , Proceedings of the 2008 IAJC-IJME International Conference, ISBM 978-1-60643-379-9, and A. G. Rehorn, J. Jiang, P. Orban, State - of - the - art methods and results in tool condition monitoring: review , Int J. Adv. Manuf Technol, 26, 2005, pp. 693-710. Unfortunately to date none of these attempts satisfactorily address the problems caused by chatter in doctor blades.
[0010] Thus there is clear need and utility for methods, compositions, and apparatuses for the detection and prevention of chatter in doctor blades. The art described in this section is not intended to constitute an admission that any patent, publication or other information referred to herein is “prior art” with respect to this invention, unless specifically designated as such. In addition, this section should not be construed to mean that a search has been made or that no other pertinent information as defined in 37 CFR §1.56(a) exists.
BRIEF SUMMARY OF THE INVENTION
[0011] At least one embodiment of the invention is directed towards a method of detecting and addressing chatter from Yankee dryer doctor blades used in the creping process, cleaning, and/or cut-off operations. The method comprises the steps of:
[0012] over a period of time, with an sensor constructed and arranged to measure the frequencies and amplitudes of vibrations in a doctor blade as it crepes a paper product, measuring the frequencies and amplitudes of the vibrations indexed by time,
[0013] collecting the measurements into a time waveform,
[0014] converting the waveform into a fast-Fourier transform having a frequency spectrum which includes distinct vibration bands,
[0015] correlating characteristics of the vibration bands with acceptable performance properties of the doctor blade and to define a baseline of acceptable vibration bands,
[0016] predicting from the correlated characteristics the degree of deviation from the baseline of acceptable vibration bands associated with doctor blade chatter, and
[0017] outputting when a data point on a vibration band exceeds the degree of deviation excessive chatter has occurred.
[0018] The sensor may be an accelerometer and/or a piezoelectric accelerometer. The measurements may be analyzed and modeled by a data processing device constructed and arranged to utilize one process selected from the group consisting of: RMS data trending, neural network techniques, multiple regression analysis, AR, ARMAX, partial least squares, and any combination thereof. At least one of the correlations may be determined by comparing characteristics of the vibration bands with blade age. The measurements may be analyzed and modeled by a data processing device constructed and arranged to utilize RMS data trending and where the determination is made at least in part by noting that the slope in a saw tooth shaped vibration band continuously increases over time with the same blade and becomes discontinuous when the blade is changed.
[0019] The method may further comprise the step of defining a deviation from the baseline due to chatter to only occur when a deviation exceeds the mean and standard deviation to of the baseline due to both an increase in magnitude and a duration of that increase greater than the mean duration of all data spikes in the waveform. The method may further comprise the steps of pre-determining the slope at which the blade is too old to be desired for use and replacing the blade when such a slope manifests on the waveform.
[0020] At least one of the correlations may be determined by comparing characteristics of the vibration bands with one factor selected from: track bearing, balance, dryer lubricity, dust levels, moisture levels, temperature, felt age, grade, furnish composition, coating chemistry, cleaning blade status (on or off), machine speed, external source vibrations, external pressure sources, and any combination thereof. The range of characteristics of the vibration bands caused by the factor may be so broad that the sensor must be capable of detecting frequency bandwidth spanning four orders of magnitude. In at least one embodiment the sensor only indirectly measures vibrations of the doctor blade because it is engaged not to the blade itself but to a blade holder which is engaged to and provides more rigid support to the blade but which does not dampen the vibration to such an extent that an accurate measurement cannot be taken. The measurements may be taken synchronously and/or asynchronously. The output may be an alarm.
[0021] Additional features and advantages are described herein, and will be apparent from, the following Detailed Description.
DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 illustrates a side view of an embodiment of the invention utilizing an accelerometer sensor measuring the operation of a doctor blade.
[0023] FIG. 2 illustrates a perspective view of an embodiment of the invention utilizing two accelerometer sensors to measure the operation of a doctor blade.
[0024] FIG. 3A is a graph of an RMS trend from an accelerometer utilizing the invention.
[0025] FIG. 3B is a graph of an expanded view of an RMS trend from an accelerometer utilizing the invention.
[0026] FIG. 4 is a graph of an RMS trend including an alarm set point from an accelerometer utilizing the invention.
[0027] FIG. 5 is a graph of a time integrated alarm and accumulated alarm from RMS data from an accelerometer utilizing the invention.
[0028] FIG. 6 is a graph of RMS residuals from a predictive model utilizing data obtained from an accelerometer utilizing the invention.
[0029] FIG. 7 is a group of graphs showing the advantage of predictive modeling for early warning chatter detection and to prevent false positive alarms.
[0030] FIG. 8 is a graph of estimated vibration frequency for different chatter mark spacings on a Yankee dryer.
[0031] FIG. 9 is a trend graph of an integrated frequency band (15-20 kHz) with and without chatter visible in the coating.
[0032] FIG. 10A is the raw sensor data for one Yankee cylinder revolution from an accelerometer utilizing the invention.
[0033] FIG. 10B is a fast Fourier transformation (FFT) of the data in FIG. 10A .
[0034] FIG. 10C is a wavelet analysis of the recorded accelerometer time waveform signal from FIG. 10A displayed as a scalogram plot.
[0035] FIG. 10D is an expanded view of the waveform from FIG. 10A showing only the zone from 0.225 to 0.272 seconds.
[0036] FIG. 10E is an expanded view of the scalogram plot in FIG. 10C showing only the zone from 0.23 to 0.264 seconds.
[0037] FIG. 11 is a graph of slope analysis of RMS trend data.
DETAILED DESCRIPTION OF THE INVENTION
[0038] The following definitions are provided to determine how terms used in this application, and in particular how the claims, are to be construed. The organization of the definitions is for convenience only and is not intended to limit any of the definitions to any particular category.
[0039] “Bevel” or “bevel surface” as used herein refers to the portion of the blade that forms the surface between the leading edge of the blade and the trailing side of the blade and is typically the “working surface” of the blade.
[0040] “Bulk” means the inverse of the density of a tissue paper web and is usually expressed in units of cm 3 /g. It is another important part of real and perceived performance of tissue paper webs. Enhancements in bulk generally add to the clothlike, absorbent perception. A portion of the bulk of a tissue paper web is imparted by creping.
[0041] “Cross Machine Direction” or “CD” means the direction perpendicular to the machine direction in the same plane of the fibrous structure and/or fibrous structure product comprising the fibrous structure.
[0042] “Doctor Blade” means a blade that is disposed adjacent to another piece of equipment such that the doctor blade can help remove from that piece of equipment a material that is disposed thereon. Doctor blades are commonly used in many different industries for many different purposes, such as, for example, their use to help remove material from a piece of equipment during a process. Examples of materials include, but are not limited to, tissue webs, paper webs, glue, residual buildup, pitch, and combinations thereof. Examples of equipment include, but are not limited to, drums, plates, Yankee dryers, and rolls. Doctor blades are commonly used in papermaking, nonwovens manufacture, the tobacco industry, and in printing, coating and adhesives processes. In certain instances, doctor blades are referred to by names that reflect at least one of the purposes for which the blade is being used.
[0043] “Fiber” means an elongate particulate having an apparent length greatly exceeding its apparent width. More specifically, and as used herein, fiber refers to such fibers suitable for a papermaking process.
[0044] “Highly polished” means surface that has been processed by a sequential progression from relatively rough grit to fine grit with suitable lubrication and is highly planar and substantially free of defects. Such sequential progression will be referred to herein as a “step polishing process.”
[0045] “Machine Direction” or “MD” means the direction parallel to the flow of the fibrous structure through the papermaking machine and/or product manufacturing equipment.
[0046] “Paper product” means any formed, fibrous structure products, traditionally, but not necessarily, comprising cellulose fibers. In one embodiment, the paper products of the present invention include tissue-towel paper products. Non-limiting examples of tissue-towel paper products include toweling, facial tissue, bath tissue, table napkins, and the like.
[0047] “Sheet control” as used herein, refers to the lack of vibrations, turbulence, edge flipping, flutter, or weaving of the web that result in a loss of control at higher speeds.
[0048] “Softness” means the tactile sensation perceived by the consumer as he/she holds a particular product, rubs it across his/her skin, or crumples it within his/her hand. This tactile sensation is provided by a combination of several physical properties. One of the most important physical properties related to softness is generally considered by those skilled in the art to be the stiffness of the paper web from which the product is made. Stiffness, in turn, is usually considered to be directly dependent on the strength of the web.
[0049] “Strength” means the ability of the product, and its constituent webs, to maintain physical integrity and to resist tearing, bursting, and shredding under use conditions.
[0050] “Tissue Paper Web”, “paper web”, “web”, “paper sheet”, “tissue paper”, “tissue product”, and “paper product” are all used interchangeably and mean sheets of paper made by a process comprising the steps of forming an aqueous, papermaking furnish, depositing this furnish on a foraminous surface, such as a Fourdrinier wire, and removing a portion of the water from the furnish (e.g., by gravity or vacuum-assisted drainage), forming an embryonic web, and in conventional tissue making processes transferring the embryonic web from the forming surface to a carrier fabric or felt, and then to the Yankee dryer, or directly to the Yankee dryer from the forming surface. Alternatively in TAD tissue making processes, the embryonic web may be transferred to another fabric or surface traveling at a lower speed than the forming surface. The web is then transferred to a fabric upon which it is through air dried to a dryness typically between 10 to 50%, and finally to a Yankee dryer for final drying and creping, after which it is wound upon a reel.
[0051] “Water Soluble” means materials that are soluble in water to at least 3%, by weight, at 25 degrees C.
[0052] In the event that the above definitions or a description stated elsewhere in this application is inconsistent with a meaning (explicit or implicit) which is commonly used, in a dictionary, or stated in a source incorporated by reference into this application, the application and the claim terms in particular are understood to be construed according to the definition or description in this application, and not according to the common definition, dictionary definition, or the definition that was incorporated by reference. In light of the above, in the event that a term can only be understood if it is construed by a dictionary, if the term is defined by the Kirk - Othmer Encyclopedia of Chemical Technology, 5th Edition, (2005), (Published by Wiley, John & Sons, Inc.) this definition shall control how the term is to be defined in the claims.
[0053] In at least one embodiment of the invention, a method detects the onset of creping doctor blade chatter. This method, by alerting machine operators that blade chatter conditions are imminent, allows operators to take corrective action avoiding runnability problems and preventing damage to the Yankee dryer surface. The method utilizes signal analysis using at least one piezoelectric accelerometer operated near the doctor blade holder. In at least one embodiment the analysis method differs from conventional CM techniques by using a time-integrated approach. As a first level approach, the signal is tracked based on both intensity above an alarm limit and duration. This allows accounting for strong vibration, but short duration, as well as weaker vibration over long periods. Enhanced monitoring is described by extending this method to predictive models using process input data, wavelet analysis for spatially resolved MD high vibration regions on the dryer surface, and trend slope analysis to predict the onset of an encroaching alarm condition. In all cases, the Yankee dryer exposure to excess vibration is accounted for by tracking the accumulated time integrated value, thus providing an historical record to help in maintenance scheduling.
[0054] In at least one embodiment the method comprises the steps of detecting directly or indirectly the vibration of the crepe doctor blade. In at least one embodiment the sensor technology is robust enough to operate in harsh environmental conditions. The conditions include one or more of high dust levels, high moisture levels and temperatures >125° C. In addition, the geometric constraints around the creping operation may require a compact sensor footprint. Furthermore, in some circumstances the sensor must be capable of detecting a frequency bandwidth spanning four orders of magnitude (for example 10 Hz to 20 kHz).
[0055] In at least one embodiment the piezoelectric accelerometer used is a typical commercially available off-the-shelf sensor that meets these criteria. Industrial accelerometers such as the SKF model CM2207 are hermetically sealed and hardened with an acceptable footprint (54×30 mm) for mounting on or near the creping doctor blade holder. In at least one embodiment the accelerometer is directly mounted on the crepe doctor blade to monitor the blade vibration as it is in contact with the coating and surface of the Yankee dryer. However, direct mounting on the doctor blade poses additional challenges with greater geometric constraints, higher temperatures, and limited blade service life requiring frequent (a few hours to 24 hrs, depending on the process and blade composition) blade changes. Therefore, in at least one embodiment the sensor mounting is positioned on the doctor blade holder. This provides an effective alternative since the blade holder is in close proximity to and in contact with the doctor blade and is itself stationary.
[0056] An illustration of one possible arrangement for mounting an accelerometer on a doctor holder is shown in FIG. 1 . In the blade holder, the doctor back plate provides a flat rigid surface for sensor mounting. In at least one embodiment the sensor mounting method is with a tapped hole on the doctor holder and thread fastener through the center of the accelerometer sensor. Adhesive mounting can also be used but at the sacrifice of higher frequency detection. Other blade holder designs used are the ladder back and super crepe as well as all other means known in the art and their equivalents. Regardless of the blade holder design, sensor mounting close to the doctor blade on a structurally rigid support with minimum dampening is the preferred method. Sensor location along the doctor back CD is dependent on the machine operation. If possible, the sensor should be located inside the sheet edge and preferably, multiple sensors are used to monitor different zones in the CD.
[0057] Referring now to FIG. 2 there is shown an illustration of accelerometer mounting inside of the sheet by the tending and drive sides on a Yankee dryer. In this case, sensors to mounted near the drive and tending side sheet edge allow detecting differences in vibration frequencies and amplitudes between the sides. Therefore, using a minimum of two sensors positioned equal distances from the tending and drive side edge is the preferred approach. In principle, a single sensor could also be used, but at the sacrifice of sensitivity and monitoring the side-to-side variation.
[0058] In at least one embodiment signal transmission from the sensors mounted near the creping doctor blade is made through hard wire cable or wireless communication to a vibration data acquisition unit, e.g., the SKF IMX-S on-line multilog system or any equivalent thereof. Data sent by the sensor can be raw, e.g., waveform, or processed through a microprocessor integrated into the sensor or signal transmission line. The data acquisition system processes the sensor data and displays the results and alarm status as well as a providing a means to achieve and retrieve data. In at least one embodiment, the data acquisition system can monitor other process variables such as the machine speed and can use a tachometer for synchronous data collection. Data collected from the acquisition system can also be routed through Ethernet or wireless to a centralized location (within a corporation or external) where data from several monitoring systems can be further analyzed. Compiling the data from several sites allows for the calculation of aggregate performance properties and relative rankings of the blade chatter levels.
[0059] Process variables for the Yankee dryer unit operation are dynamic with varying time scales from minutes to days. Process variables such as creping blade age, felt age, grade, furnish, coating chemistry, cleaning blade status (on or off), machine speed, etc., all contribute to the vibration signature observed on the creping doctor. In addition, vibration originating from other sources such as fan pump, Yankee dryer bearings, pressure roll, overhead crane, etc. can also propagate through the process structure to the crepe blade. The aggregate of the vibration sources results in the overall vibration signature detected by the sensor. For a piezoelectric accelerometer sensor, the vibration signature monitored is a time waveform that can be collected synchronous or asynchronous relative to the Yankee dryer rotation. Taking a fast-Fourier transform (FFT) of the waveform gives a frequency spectrum that provides unique vibration frequencies and/or bands. Further data reduction is made by extracting the root-mean-square (RMS) from the FFT power spectral density to get an overall and/or bandwidth vibration magnitude value to trend over time.
[0060] The RMS trend from an accelerometer mounted on the creping doctor blade holder will show natural variations under normal operating conditions because of the process dynamics. The complexity and multiple interactions from the different vibration sources makes identifying specific process variables contributing to a unique vibration frequency or band a difficult task. However, some general features such as blade age are clearly observed in the RMS trend as a saw tooth pattern. Installing a new blade will reduce the RMS by improved efficiency (reduced drag) in cutting through the coating and removing the sheet. As the blade degrades over time, the drag will increase resulting in the RMS increasing. To illustrate this point, FIG. 3 shows an RMS trend for 0-10 kHz bandwidth data collected over II days. The trend is composed of a natural process variation baseline associated with the creping doctor blade age as well as periods where the RMS value spikes relative to the baseline.
[0061] Different features on FIG. 3 are highlighted and a zoomed area shows the effect of the creping blade age on the RMS trend (vertical markers indicate periods where a blade change occurred). Periods where the RMS levels spike can potentially lead to degradation of the coating and/or the dryer surface. The vibration source associated with these spikes is not always obvious, and often requires further investigation of the process and operating (human and mechanical) conditions. Degradation of the Yankee coating or dryer surface may occur from a single RMS spike event or a cumulative effect over time. Therefore, minimizing the frequency and amplitude of the RMS excursions above the natural baseline is a best practice scenario for maintaining runnability and asset protection.
[0062] As a first level for chatter monitoring, the state of the creping doctor blade vibration is tracked by using an nσ alarm based on the mean and standard deviation (a) of RMS trend data that excludes the spiked periods and no visible chatter is present in the coating or dryer surface. Alarming sensitivity is based on the user selected number of standard deviations from the mean. Alarming (real-time) is based on the RMS level or RMS level and time duration. For just RMS alarming, an alarm signal (visual, audible or combination) is sent to the operator and stored in a database when the RMS value is greater than the ns alarm level setting. Different states of alarming can be selected by using multiple ns settings. For example, a 2σ alarm level can be a warning alarm alerting the operator the RMS value is trending upward, but not yet reaching a critical state. If the RMS value continues to trend upward past the 3σ alarm setting then a critical alarm can be sent to the operator. This method of alarming is commonly found in commercial condition monitoring systems used in predictive maintenance on rotating machinery. In this application, condition monitoring tracks bearing, balance, and overall integrity health on machinery. As the bearing wears the RMS trend from a sensor (typically an accelerometer mounted near the bearing of the rotating shaft) will gradually increase indicating that bearing maintenance such as replacement or lubrication is needed. If left unattended the RMS level would remain at a high level or continue to climb upward.
[0063] Unlike traditional condition health monitoring, the dynamics of the creping process can result in large RMS variations without developing chatter. Therefore, a transient RMS spike above an nσ alarm level does not necessarily warrant an alarm event. However, as the duration of the RMS value above the alarm setting increases, the probability of developing chatter increases. In this alarming mode, the alarm signal strength (alarm*) is a function of both the RMS value >nσ alarm level (RMS + ) and the duration the RMS + signal remains above the alarm level. The expression for the alarm* signal is given by
[0000] Alarm*( RMS,t )=( w RMS RMS + )( w,t )
[0000] where W RMS and w t are weighting parameters or functions, t is the time above the alarm level, and RMS + is the difference between the RMS signal and the nσ alarm value. Trending the time integrated alarm signal will show variations >0 for conditions when the RMS level is above the nσ set-point and increases with time. This method addresses both short duration high RMS values as well as RMS values that remain slightly higher than the alarm level for long periods.
[0064] The second mode of alarming is based on the accumulative effect of alarm* over time and can be trended continuously as well as reported daily, weekly, monthly, or yearly. The accumulated alarm* Acc is given by
[0000] Alarm* Acc =Σ Log(Alarm*)
[0000] and represents the total excess vibration the Yankee dryer is exposed to over time. Minimizing the frequency, duration, and amplitude of the alarm* Acc will reduce the Yankee exposure to critical vibration levels thereby minimizing maintenance and extending the asset service life. Trending the alarm* Acc is useful for evaluating and predicting different maintenance levels for the Yankee dryer ranging from simple inspection to surface reconditioning. The accumulated alarm information also helps to identify differences in operating procedures, e.g., between workers shifts, grades manufactured, furnish, etc., where the vibration levels may trend abnormally high.
[0065] An example using this alarming strategy for the RMS vibration data collected over 11 days is shown in FIG. 4 for a 1.0 minute sampling rate. FIG. 4 shows the measured RMS data collected with a 3σ alarm level determined from an independent training set of data. The plot shows the historical RMS trend recorded with the 3σ alarm level (dashed line). FIG. 5 shows the resulting time integrated alarm* value using unit weighting values. Under normal operating conditions alarm*=0.0, since the RMS value is below the 3σ alarm level. Also shown on FIG. 5 is the accumulated alarm* value to track the total excess vibration the dryer surface has been exposed to over the 11 day period.
[0066] In at least one embodiment the alarming method also involves a predictive model that reduces or removes the process dynamics contributing to the measured vibration. The benefit of using a predictive model is improved alarming sensitivity and reduction in false positive alarms. Numerous model building techniques such as neural network (NN), multiple regression, autoregressive (AR), autoregressive moving average with exogenous terms (ARMAX), state-space, partial least squares, and any combination thereof, can be used to develop a predictive model based on the waveform, frequency spectrum, or RMS trend data. Ideally, model construction begins by collecting process bump testing data to develop cause-and-effect relationships. However, bump testing is generally restricted to a limited range of process changes to minimize quality and production loses. To address this issue data collection over long periods is required to capture process changes for model tuning. Alternatively, continuous tuning (learning) using adaptive algorithms can be used to update the model. Using a predictive model requires process input data that can be collected from the distributed control system or monitored directly with the vibration data acquisition system. In either case, the process data collected is used as a model input.
[0067] An example illustrating a predictive NN model of the RMS trend from FIG. 4 based on a process model with 25 input variables is shown in FIG. 6 as a plot of the residuals (difference between the measured and predicted value). In this example, the creping blade age dependency is modeled by applying a transformation on the blade change data that is reported as the time of the event to force the model to have similar behavior. The transformation uses a fixed slope based on the average obtained from the RMS trend measurements over the life of a blade. Large residuals represent a process condition not captured by data in the model building step. The large residuals may or may not be an actual chatter condition, but are an indication that excess vibration has propagated to the creping doctor blade.
[0068] The advantaged of using the predictive model for alarming is shown in FIG. 7 for time integrated alarming. The zoomed areas show two different cases. The LHS figure shows the predicted (residual) alarm* value appearing before the alarm* value from FIG. 4 data. In this case, the predicted alarm* value occurs almost 60 minutes before the standard alarm* value. The early alarming results from lower 3σ alarm level. The RHS plot shows just the opposite effect with alarm* occurring first. In this case, the NN model accounts for the contribution to RMS from the process conditions and reduces or removes the occurrence of a false positive alarm condition.
[0069] In at least one embodiment of the invention, a vibration frequency or band is monitored with alarming based on simple nσ alarm level or time integrated alarming. Unlike many of the mechanical vibration sources that occur at frequencies <500 Hz, chatter appears at higher frequencies. In cases where chatter is visible in the coating or dryer surface an estimate of the frequency range is made by measuring the spacing between the chatter marks and knowing the dryer speed. As the chatter mark spacing decreases the chatter frequency increases as shown in FIG. 8 for a fixed 6000 FPM machine speed. Even at a chatter mark spacing of 1 inch the estimated vibration frequency at this machine speed is >1000 Hz. In the development of chatter by the stick-slip mechanism ( S. Archer et. al., Tissue World Americas 2008) visible chatter mark spacing is typically much less than an inch. Therefore, high frequency band monitoring can improve the measurement sensitivity to detect chatter. The sensitivity gain is obtained by focusing on smaller spectral regions compared to monitoring the overall RMS that can be affected by low frequency non-chatter events, e.g., the fan pump. In addition, changes in a narrow spectral region may be attenuated in the overall RMS value because of averaging with the surrounding spectral features.
[0070] Trend data shown in FIG. 9 highlights the difference in data observed for the integrated frequency band (15-20 kHz) at conditions with and without chatter. The first section of FIG. 9 shows the integrated frequency trend when no chatter is visibly observed in the coating or dryer surface. When visible chatter did occur in the coating, a step change in the integrated frequency resulted. Monitoring different integrated frequency bands is directly applicable with the simple nσ or time integrated alarm* methods previously discussed.
[0071] In at least one embodiment of the invention, there is provided a means to monitor and alarm the early onset of chatter through wavelet analysis of the time waveform. For synchronous data collection, the time waveform represents the vibration signal measured for one complete rotation of the Yankee dryer. Taking the continuous wavelet transformation (CWT) of the time waveform sensor data parses out the vibration intensity and frequency information as a function of time. By knowing the Yankee dryer speed and diameter, a transformation from the time to the MD spatial domain is made. The MD vibration frequency and intensity is useful for tracking specific spatial zones to determine the onset of potential chatter. For example, the MD can be divided into n number of zones to trend an averaged or cumulative vibration frequency, band, or local RMS value. Alarming using either the simple nσ or time integrated approach can then be used to alert operators of potential problems. In particular, the wavelet technique will provide an early alarming condition for cases when chatter is initially developed locally before the formation of a chatter band around the dryer circumference.
[0072] An example of using the wavelet analysis on the time waveform vibration sensor to data is shown in FIG. 10 . The plot labeled FIG. 10A represents the raw sensor data or waveform collected from a sensor mounted on the doctor back as shown in FIG. 1 . The data was collected over 0.64 seconds representing one cylinder revolution. Spectral features and intensity from the FFT analysis (plot labeled FIG. 10B ) is the integrated result over 0.64 seconds, so the strong frequency bands observed near 7800 and 11800 Hz represents the accumulated effect. Identifying unique spectral features from the FFT is useful in data interpretation, but lacks temporal information. Wavelet analysis of the waveform addresses this issue by extracting vibration frequency and intensity information at different times. By applying wavelet analysis to the waveform, a scalogram plot is constructed (labeled FIG. 10C ) to display the square magnitude of the complex wavelet coefficients from the CWT to display frequency and intensity as a function of time. Expanded views of the waveform (labeled FIG. 10D ) and scalogram (labeled FIG. 10E ) illustrate clearly the correlation between the waveform features and spatial vibration frequencies. For example, in the zone between 0.234 and 0.236 seconds an intense band of vibration frequencies >10 kHz is observed. This frequency band shows up sporadically throughout the scalogram, but at this particular time (location), the intensity is maximum indicating localized intense high frequency vibration.
[0073] In at least one embodiment of the invention, there is a means to monitor the onset of early chatter detection by slope analysis of the vibration frequency band or RMS trend. A characteristic feature for trend plots of RMS or selected vibration frequency bands is the effect of the creping doctor blade age. A newly installed blade causes an initial decrease in the RMS trend. As the blade ages and wears the trend signal will increase over time. Tracking the characteristic features of the trend such as the slope and marginal slope (2 nd derivative) are indicators of the process state used in assessing whether a potential chatter condition is approaching. FIG. 11 shows variations in the RMS trend slope that occurs under “normal” conditions between doctor blade changes. Cases where the RMS increases to higher level than the normal running baseline is often preceded by a sharp increase in the slope. Tracking the slope then provides a means of predicting whether the RMS value is moving toward a higher trajectory.
[0074] In at least one embodiment of the invention, the method comprises a simple alerting method based on the time integrated alarm* value that could be color coded or audible. Color coded alarming utilizes a set of colors to indicate the current alarming state, e.g., green for normal operation, yellow for an approaching chatter condition, and red for the presence of a potential critical chatter condition. In this case, the time integrated chatter condition accounts for both low and high RMS values above the alarm level at long and short time durations respectively.
[0075] While this invention may be embodied in many different forms, there are shown in the drawings and described in detail herein specific preferred embodiments of the invention. The present disclosure is an exemplification of the principles of the invention and is not intended to limit the invention to the particular embodiments illustrated. All patents, patent applications, scientific papers, and any other referenced materials mentioned herein are incorporated by reference in their entirety. Furthermore, the invention encompasses any possible combination of some or all of the various embodiments described herein and incorporated herein.
[0076] The above disclosure is intended to be illustrative and not exhaustive. This description will suggest many variations and alternatives to one of ordinary skill in this art. All these alternatives and variations are intended to be included within the scope of the claims where the term “comprising” means “including, but not limited to”. Those familiar with the art may recognize other equivalents to the specific embodiments described herein which equivalents are also intended to be encompassed by the claims.
[0077] All ranges and parameters disclosed herein are understood to encompass any and all subranges subsumed therein, and every number between the endpoints. For example, a stated range of “1 to 10” should be considered to include any and all subranges between (and inclusive of) the minimum value of 1 and the maximum value of 10; that is, all subranges beginning with a minimum value of 1 or more, (e.g. 1 to 6.1), and ending with a maximum value of 10 or less, (e.g. 2.3 to 9.4, 3 to 8, 4 to 7), and finally to each number 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 contained within the range.
[0078] This completes the description of the preferred and alternate embodiments of the invention. Those skilled in the art may recognize other equivalents to the specific embodiment described herein which equivalents are intended to be encompassed by the claims attached hereto. | The invention embodies the application of different combinations of the monitoring and data processing aspects as a means to develop an early warning chatter alarming system. Configuring an early warning chatter alarming system can be as simple as using nσ alarm settings to develop an alarming strategy from different trend conditions such as overall RMS, selected vibration frequencies, slope analysis, and wavelet analysis. A higher level of alarming is provided by using a time integrated approach to account for both intensity of the alarm variable and duration. Combining these different aspects with a predictive model incorporates process-operating conditions to enhance the alarming sensitivity for earlier detection and reduce false positives. Finally, combining the different alarming aspects with a rule-based decision making approach such as fuzzy logic allows alarming based on qualitative analysis of different data streams. | 3 |
RELATED APPLICATIONS
[0001] This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 62/204,006, filed Aug. 12, 2015, entitled “SELF HEALING STEEL COATING” incorporated herein by reference in entirety.
BACKGROUND
[0002] Steel reinforced concrete is commonly employed in civil engineering contexts, in particular with infrastructure developments such as bridges, roads and tunnels, but also in commercial construction. Ribbed steel rods, or rebar (reinforcement bar), is typically inserted into a concrete form, and concrete molded (poured) around the inserted rebar forming an encapsulated steel which complements the compressive strength of the concrete. Premature failure of reinforced concrete has often been associated with corrosion and oxidation of the embedded steel members.
[0003] In particular, steel-reinforced concrete is by far the most widely used infrastructure material, with approximately 7 billion cubic meters currently in place in the U.S. alone. An additional 380 million cubic meters are added each year. Electrochemical corrosion, which occurs when aggressive media break down the protective oxide film on reinforcing steel and enable the production of rust, is one of the most significant contributors to service life reduction in steel-reinforced concrete
SUMMARY
[0004] A self-healing coating for reinforcing steel embedded in concrete includes emulsion derived microcapsules having a healing agent disposed in particles adapted for dispersion through a liquid, and a coating medium adapted to be disposed on a structural steel surface to form a coating for corrosion prevention. The particles (microcapsules) are dispersed in the liquid coating medium for being applied to the surface and are configured to rupture and release the healing agent onto the surface in response to a compromise of the coating, such as being dropped or dragged on a construction site. The self-healing agent, such as Tung oil, complements the protective properties of the coating medium by flowing into regions where the coating medium has been scraped off, flaked off, or otherwise undergone compromise. Alternatively, post-installation corrosive influences, such as rust and oxidation, can also cause rupture of the particles to abate corrosion in the concrete-encased steel members. Configurations herein are based, in part, on the observation that steel-reinforced concrete remains a substantial structural component for many infrastructure and commercial construction needs. The symbiotic combination of the tensile strength of steel coupled with the compressive strength of concrete provides a versatile load bearing construction medium. Unfortunately, reinforcing steel encased in the concrete, typically ribbed steel rods known as rebar, suffers from corrosion and oxidation within the concrete. Rebar is typically coated with a rust preventative, but the rough environment of construction sites coupled with course aggregate (rocks) in the concrete poured over the rebar during installation can often scratch and compromise the rebar, leaving exposed regions susceptible to corrosive elements. Accordingly, configurations herein substantially overcome the above described shortcomings of conventional rust preventative coatings and epoxies by providing a self-healing coating having microcapsules filled with a healing agent dispersed as particles throughout the self-healing coating. The microcapsules have a polymer coating responsive to physical abrasion by rupturing and distributing the healing agent around the damaged region. Following encapsulation in concrete, the microcapsule particles remain on the coating and are responsive to oxidation and corrosion by rupturing and releasing the healing agent across the oxidation region for retarding corrosion.
[0005] In an example configuration, the healing agent is Tung oil, and the self-healing coating is a liquid epoxy medium similar to conventional rust preventative coatings. Upon construction site handling, typically by being dropped or dragged in conjunction with hard surfaces, scratched or abraded epoxy regions release the healing agent from the microcapsules (particles) ruptured by the damage. Scratched epoxy regions therefore result in the healing agent filling in the scratch to compensate for the breached coating. However, any suitable healing agent may be encapsulated in the particles and other liquid mediums in addition to epoxy may be employed for coating the structural steel.
[0006] In further detail, the method for disposing a self-healing coating on reinforcing steel rebar as disclosed herein includes preparing a microcapsule emulsion for generating particles containing a healing agent surrounded by a polymer shell, and combining the particles with a liquid coating for preventing oxidation of steel members.
[0007] Either prior to or during formation concrete molds, a spray or brush process applies the coating with the particles to a structural reinforcing member (rebar). The construction process often involves introducing the coated, structural reinforcing member into a compromising environment, such that the compromising environment causes the shell to rupture and release the healing agent. The healing agent complements the corrosion prevention of the coating by flowing into and covering gaps in a compromised region of the liquid coating upon release from a ruptured shell.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The foregoing and other objects, features and advantages of the invention will be apparent from the following description of particular embodiments of the invention, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.
[0009] FIG. 1 is a context diagram of a construction environment suitable for use with configurations disclosed herein;
[0010] FIG. 2 is a side cutaway view of a structural member with the self-healing coating applied;
[0011] FIGS. 3 a and 3 b show ruptured microcapsules performing self-healing on the structural member of FIG. 2 ;
[0012] FIG. 4 shows a top section of the healing agent flowing from microcapsules onto a compromised region; and
[0013] FIG. 5 shows a distribution of the microcapsule diameter of the particles dispersed through the coating of FIGS. 2-4 .
DETAILED DESCRIPTION
[0014] The figures and examples below depict an anticorrosion coating for structural steel members such as rebar that employs microcapsules containing a healing agent for releasing the healing agent in response to abrasion, damage or pH changes indicative of corrosive infiltration in reinforced concrete. The anti-corrosion coating, such as a polymer or resin based mixture, distributes poly(urea-formaldehyde) microcapsules of Tung oil or other healing agent along the surface of the rebar. The microcapsules of Tung oil define a secondary phase healing agent releasable in response to detected damage or corrosion for protecting the steel surface from corrosive infiltration from water, road salt and other foreign elements that permeate the concrete and cause degradation of the reinforcing steel.
[0015] The most common method of preventing steel corrosion in reinforced concrete is the use of epoxy-coated rebar (ECR). The epoxy thermoset acts as a physical barrier that can prevent, or significantly delay, the onset of corrosion. Other methods of corrosion prevention are either significantly more expensive (e.g. using stainless steel rebar) or significantly more difficult to use in the field (e.g. galvanic protection). However, ECR is only effective if the brittle epoxy coating is kept in excellent condition. Chips or cracks in the epoxy provide aggressive media access to the reinforcing steel and negate the protective properties of the system. Although improvements in the manufacture of ECR have reduced the number of imperfections, flaws are still routinely encountered. This project reports the first use of self-healing coatings for rebar in steel-reinforced concrete. When damage occurs in self-healing coatings, microcapsules rupture and healing agent passivates the surface and restores the physical barrier to corrosive species. Based on preliminary results, the self-healing coatings may extend infrastructure lifetimes threefold. Since the disclosed coatings are applied similarly to conventional epoxy coatings, usage is less expensive than stainless steel rebar, which is preferentially used over ECR for its improve corrosion resistance.
[0016] Conventional approaches suffer from the shortcoming of phase change, allowing only a one-time healing action, or a vascular approach, which includes a fluidic network. One-time healing approaches impose that once the healing agent has reacted and gone from a monomer (liquid) to a polymer (solid), there can be no more healing in that location. Vascular approaches are a strategy for compensating for the lack of a healing agent in secondary phase-based approaches, by including a network through which healing agent can flow. However, this is not feasible in a coating. Secondary phase approaches employ a coating material to which a second phase is added, such as fluid contained capsules, however sometimes there can be natural phase separation of the healing agent from the coating matrix, rendering a capsule unnecessary.
[0017] Depicted below is a particular configuration of the self-healing coating for reinforcing steel embedded in concrete, such as rebar. FIG. 1 is a context diagram of a construction environment suitable for use with configurations disclosed herein.
[0018] Referring to FIG. 1 , in a construction environment 100 , a particular configuration applies the self-healing coating to structural steel members such as rebar (reinforcement bar) 110 , which is typically stacked or piled near a mold or form 120 for concrete. Stacking or piling the rebar 110 causes individual bars 110 ′ to impact and frictionally engage other rebar 110 , scraping or scratching the exterior surface and any applied coating. The stacked rebar 110 is eventually disposed in the form 120 , such as by a crane cable 112 , where it is bound, welded or otherwise attached to other rebar 110 members. The form 120 is filled with concrete 122 , typically by a chute 124 or pump hose. Typical concrete has various sizes of aggregate 126 , which are simply rocks or other solid mass, which can impact the rebar 110 as the concrete 122 falls into the mold.
[0019] In sum, structural steel members such as rebar encounter many manipulations which can cause physical damage or discontinuities in the rebar coating. In conventional approaches, the discontinuities represent paths for corrosion and degradation. In contrast, in configurations described below, physical agitation of the coating ruptures the microcapsules and releases the healing agent.
[0020] FIG. 2 is a side cutaway view of a structural member with the self-healing coating applied. Referring to FIGS. 1 and 2 , a structural steel member 140 such as rebar is coated with the self-healing coating 150 . The coating 150 is expected to be a liquid medium such as epoxy or other rugged substance that provides substantial corrosion protections while intact. In contrast to conventional approaches, microcapsules 152 are distributed throughout the coating 150 . The ratio of particles dispersed in the liquid medium is 10-20% of the coating. The microcapsules 152 have a polymer shell 154 surrounding a cavity 156 for containing a quantity of the healing agent 160 , such as Tung oil. In an example configuration, a thickness of the applied coating is in a range between 0 . 02 and 0 . 19 mm, and the size of the microcapsule particles is in a range from 0 . 20 mm- 0 . 65 mm and an average particle size of substantially around 0 . 3 mm. Accordingly, a substantial quantity of the microcapsules may be in contact with the rebar surface 142 , and others may meet the outer surface 158 of the coating. Dispersion of the microcapsules 152 (particles) through the coating 150 ensures a robust response of healing agent 160 upon physical compromise of the coating 150 .
[0021] FIGS. 3 a and 3 b show ruptured microcapsules performing self-healing on the structural member of FIG. 2 . Particle rupture may result from physical compromise of the applied coating surface prior to or during concrete casting including the coated reinforcing members, as in FIG. 3 a , or may result from oxidation of concrete-encased steel onto which the coating has been applied, as in FIG. 3 b . Referring to FIGS. 2 and 3 a , a scratch or impact creates a void 170 or rupture in the self-healing coating 158 . As a result, some of the microcapsules 152 are breached, and allow the healing agent 160 (Tung oil) to flow into the void 170 and cover the rebar surface 142 . Drying oils such as Tung oil and linseed oil have been noted regarding their healing properties and encapsulation. Upon exposure to air, Tung oil will polymerize into a tough, glossy, waterproof coating, effectively compensating for the loss of protection from the damaged area and providing the healing effect. These characteristics have made drying oils a valuable component in paints, varnishes, and printing inks. Alternative healing agents may be encapsulated based on healing properties.
[0022] Referring to FIGS. 2 and 3 b , in another scenario, corrosion from elemental factors, such as rain, road salt and other factors, may infiltrate the concrete 168 through a crack 180 . Due to the porous nature of the concrete, corrosive influences may still enter even unbreached concrete 168 . Corrosion 182 on the surface of the rebar 140 causes a breach 174 in the polymer shell 154 , which distributes the healing agent 160 in a protective flow 161 over the compromised region along the rebar surface 142 . Further, pH changes resulting from the corrosive influences may also facilitate rupture of the microcapsules 152 .
[0023] FIG. 4 shows a top section view of the healing agent 160 flowing from microcapsules 152 onto a compromised region. Referring to FIGS. 2 and 4 , corrosion 182 caused by the crack 180 or other factors results in the compromised region, is then covered by the healing agent 160 flowing from the breach 174 in the microcapsules 152 to form the protective flow 161 . In implementation, reinforced concrete having rebar with the applied self-healing coating has an extended service live of up to 300% over reinforced concreate without coated rebar.
[0024] FIG. 5 shows a distribution 500 of the microcapsule diameter of the particles dispersed through the coating of FIGS. 2-4 . Formation of the microcapsules 152 as detailed further below results in a quantity of microcapsules 152 distributed according to a count 510 for a subrange of sizes 520 . Referring to FIGS. 2 and 5 , the microcapsules 152 are defined by particles that range in size from 0.20 mm-0.65 mm in diameter. Various changes to the size of the microcapsules 152 , as well as a thickness of the polymer shell 154 surrounding and defining the cavity 156 holding the healing agent 160 , may be achieved in alternate configurations.
[0025] The healing agent encapsulated in the microcapsules may be any suitable substance that promotes passivity, longevity and/or mitigates corrosion or compromise of the structural steel member. In the example configuration, Tung oil has shown to be an effective healing agent, and the Tung oil microcapsules are generated as described below. The microcapsules are formed from an emulsion, generally regarded as a mixture of two or more liquids that are normally immiscible. The formed microcapsules are particles, nanoparticles or other particles dispersed throughout a liquid medium for application as a coating on reinforcing members embedded in concrete prior to curing.
[0026] The procedure used for encapsulating Tung oil was begins with an oil-in-water emulsion to which the following components were added: ethyl maleic anhydride (EMA) solution as a surfactant, resorcinol to stabilize the solution, ammonium chloride to provide a pH buffer, and urea reacting with formaldehyde to form the polymer shells. At room temperature, 200 mL of deionized water, 25 mL of 2.5 wt. % EMA solution, 0.5 g of resorcinol, 0.5 g of ammonium chloride, and 5 g of urea were mixed fully in a 500 mL beaker. Following this, the pH of the solution was adjusted from 2.7 to 3.5 using a dilute sodium hydroxide solution in order to control the morphology of the polymer shells. This solution was placed into a room temperature water bath and stirred at 400 rpm as 50 mL of Tung oil was slowly added into the solution. The resulting mixture was mechanically stirred at 400 rpm for 10 minutes to form a stabilized emulsion, after which 13 g of 37 wt. % formaldehyde solution was added. The temperature of the solution was raised to 60° C. for 4 hours at 400 rpm to facilitate the polymerization reaction between urea and formaldehyde. The solution was then removed from the oil bath and stirred as it cooled to room temperature over 6 hours.
[0027] To extract the microcapsules, the mixture was vacuum filtered with coarse filter paper, then washed with deionized water and acetone, respectively. Finally, the microcapsules were air-dried for 48 hours before they could be used. Both poly[(phenyl isocyanate)-co-formaldehyde] (isocyanate pre-polymer, number of reactive groups per molecule˜3.0, MW˜375) and poly(vinyl alcohol) (PVA, MW-9,000-10,000, 80% hydrolyzed) were obtained. 2-methylbenzothiazole, ethylenediamine, and tetraethylenepentamine (TEPA) were procured from various sources. All chemicals were used without any purification.
[0028] Encapsulation of Tung oil is achievable using the same approach as that used for Encapsulation of 2-methylbenzothiazole, as follows. At room temperature, 40 mL of deionized water, 5 mL of 2.5 wt.% EMA solution, 0.1 g of resorcinol, 0.1 g of ammonium chloride, and 1 g of urea were mixed fully in a 500 mL beaker. Once the solids were completely dissolved, the solution was adjusted to a pH of 3.5 using dilute sodium hydroxide. This was placed into a room temperature water bath and stirred at 400 rpm as 5 mL of 2-methylbenzothiazole was slowly added to the solution. The resulting mixture was mechanically stirred at 400 rpm for 10 minutes to form a stabilized emulsion, after which 2.6 g of 37 wt. % formaldehyde solution was added. The temperature of the solution was raised to 60° C. for 4 hours at 400 rpm to facilitate a polymerization reaction. The resulting solution was filtered using vacuum filtration and rinsed with deionized water and acetone.
[0029] While the system and methods defined herein have been particularly shown and described with references to embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention encompassed by the appended claims. | A self-healing coating for reinforcing steel embedded in concrete includes emulsion derived microcapsules having a healing agent and adapted for dispersion through a liquid coating medium for application on a structural steel surface to form a coating for corrosion prevention. The microcapsule particles are dispersed in the coating medium for being disposed on the surface and are configured to rupture and release the healing agent onto the surface in response to a compromise of the coating, such as being dropped or dragged on a construction site. The self-healing agent, such as Tung oil, complements the protective properties of the coating medium by flowing into regions where the coating medium has been scraped off, flaked off, or otherwise undergone compromise. Alternatively, post-installation corrosive influences, such as rust and oxidation, can also cause rupture of the particles to abate corrosion in the concrete-encased steel members. | 2 |
RELATED APPLICATIONS
[0001] This application is a continuation of utility Application Ser. No. 14,695,986, filed Apr. 24, 2015, which is a continuation-in-part of utility Application Ser. No. 12/434,430, filed May 1, 2009, which is a continuation-in-part of utility Application Ser. No. 11 /929,670, filed Oct. 30, 2007, and claims priority to provisional Application No. 60/855,340, filed Oct. 30, 2006, all by Alan Gilbert and all entitled FLAME-RETARDANT MATERIALS AND SYSTEMS.
FIELD OF THE INVENTION
[0002] The invention relates generally to flame-retardant materials and, more particularly, to the use of porous particles to store flame-retardant, non-flammable, or oxygen displacing gases, which are applied to or stored in various materials, the stored or entrapped gas released on occurrence of selected conditions to suppress or retard flame or fire.
SUMMARY OF THE INVENTION
[0003] The invention includes a flame-retardant composition comprising a nanocube, metal organic framework or zeolite; both having a plurality of porosities formed therein; a flame-retardant material occupying the porosities; and a matrix material in which said material having a plurality of porosities are dispersed. The flame-retardant may further comprise a sealant applied to at least a portion of the material having a plurality of porosities, wherein the sealant substantially prevents the gas from escaping the porosities in the material. It may also include a composition wherein the matrix is a flame-retardant composition adapted to be applied to fabric. The invention may also include material having a plurality of porosities formed of a material that will break down and release the gas in the presence of water. The same material will also break down and release the gas in the presence of flame. The material having a plurality of porosities containing the flame-retardant material may also be sealed with a sealant that is a polymer material.
[0004] Another aspect of the invention includes a flame-retardant composition comprising a material having a plurality of porosities formed therein; an nonflammable, oxygen-displacing gas occupying the porosities; and a sealant applied to at least a portion of the material having a plurality of porosities, wherein the sealant substantially prevents the gas from escaping the porosities in the material having a plurality of porosities. This embodiment may also include a matrix that is a polymer material. This composition may include a matrix that is a flame-retardant composition adapted to be applied to a variety of substrates. This composition may include material having a plurality of porosities that are formed of a material that will break down and release the gas in the presence of water or material having a plurality of porosities formed of a material that will break down and release the gas in the presence of flame.
DETAILED DESCRIPTION
[0005] A number of unique substances known as “nanocubes” were discovered and studied at various universities around the United States. These nanocubes are of a family of organometallic (typically called metal organic frameworks or MOFs) materials that are highly crystalline, porous materials, having more free volume than most zeolites. The chemical functionality of the pores of these nanocubes or MOFs can be varied for used in storage or encapsulation of gases; thus allowing for an enormous storage capacity. One proposed stored gas is hydrogen for use as a fuel cell. One method of producing such nanocubes or MOFs is found in U.S. Pat. No. 7,119,219, issued Oct. 10, 2006, to Mueller et al. Other methods and resulting MOF structures can be found in U.S. Pat. Nos. 7,196,210; 6,930,193; and 5,648,508, all to Yaghi et al.
[0006] An example of such an existing nanocube is an isoreticular MOF that employs zinc-oxygen clusters (Zn 4 O), which are tetrahedral clusters with the oxygen atom at the center of the tetrahedron, interconnected with benzene ring struts. Some of the benzene ring struts used have been 1, 4-benzenedicarboxylate and a cyclobutyl-benzene strut. Namely, the cyclobutyl-benzene MOF has been used to encapsulate methane.
[0007] However, even with the advances in MOF or nanocube technology, applications for these substances are relatively limited. Moreover, the number of MOF substances remains relatively small (numbering less than 500). The preferred embodiment of the present invention, though, is directed toward an application of these MOFs or nanocubes, namely their use with fire-retardant compounds contained within them.
[0008] As with previously known nanocubes, the MOFs for use in flame-retardant applications include zinc-oxygen (OZn 4 ) clusters having benzene ring struts. The preferred MOF is known as MOF-177. MOF-177 is known to absorb up to 140 times its weight in gas, such as carbon dioxide (CO 2 ), at pressures between about 32 and 36 bar.
[0009] This and similar nanocubes or MOFs can be employed to contain or encapsulate or otherwise contain an oxygen displacing, non-flammable, or fire retardant gas, such as diatomic nitrogen, carbon dioxide, or argon. The gas is encapsulated by exposure of the MOF material to the gas at elevated pressure. In the case of MOF-177 and CO 2 , a quantity of MOF particles are exposed to CO 2 at elevated pressure, preferably between 32 and 36 bar, thus impregnating the porous structure with a greater volume of gas than might be adsorbed at standard or ambient conditions.
[0010] Another substance exhibiting flame-retardant properties in accordance with the present invention is the zeolite. Zeolites are aluminosilicate minerals and have a microporous structure (pores smaller than 2 nm). As of January 2008, 175 unique zeolite frameworks have been identified, and over 80 naturally occurring zeolites are known. Zeolites have a porous structure (i.e., very high porosity) that can accommodate a wide variety of cations, such as Na + , K + , Ca 2+ , Mg 2+ and others. These positive ions are rather loosely held and can readily be exchanged for others in a contact solution. Some of the more common mineral zeolites are analcime, chabazite, heulandite, natrolite, phillipsite, and stilbite. An example mineral formula is: Na 2 Al 2 Si 3 O 10 −2H 2 O, the formula for natrolite.
[0011] Zeolites are the aluminosilicate members of the family of microporous solids known as “molecular sieves.” The term molecular sieve refers to a particular property of these materials, i.e., the ability to selectively sort molecules based primarily on a size exclusion process. This is due to a very regular pore structure of molecular dimensions. The maximum size of the molecular or ionic species that can enter the pores of a zeolite is controlled by the dimensions of the channels. These are conventionally defined by the ring size of the aperture where, for example, the term “8-ring” refers to a closed loop that is built from 8 tetrahedrally coordinated silicon (or aluminum) atoms and 8 oxygen atoms.
[0012] Like MOFs, zeolites can be impregnated with an nonflammable, oxygen-displacing gas, such as CO 2 , by exposure to the gas at elevated pressures, so that the porosities are filled with a greater volume of gas than might be adsorbed under standard temperature and pressure or ambient conditions. Both MOFs and zeolites are particles or particulate matter having high porosity and internal surface area capable of being impregnated with substantial volumes of gas.
[0013] Still another porous particle is halloysite, a naturally occurring aluminosilicate nanotube. Halloysite is a two-layered aluminosilicate, with a predominantly hollow tubular structure in the submicron range and chemically similar to kaolin. The size of halloysite particles varies within 1-15 microns of length and 10-150 nm of inner diameter, depending on the deposits from which it is mined.
[0014] As a “nanotube,” halloysite has a single porosity. As with the MOF and zeolite, this porosity is open to the atmosphere (at at least one if not both ends) and is therefore susceptible to being impregnated with a nonflammable gas. And also as with the MOF and zeolite, at least the openings of the halloysite are sealed to prevent premature, inadvertent, or accidental release of the gas contained in the porosity.
[0015] Yet another porous particle is the compound cyclodextrin. Cyclodextrins are a family of compounds comprising saccharide (sugar) molecules bound in a ring configuration. The resulting molecular structure is a toroid or “donut” shape with a single porosity in its “middle.” Like halloysite, the single porosity of cyclodextrin is open at its ends to the atmosphere and susceptible to impregnation or filling with a nonflammable gas. Also similarly, at least the openings of the cyclodextrin particle are sealed to prevent premature, inadvertent, or accidental release of the gas contained in the porosity.
[0016] As demonstrated in the Example below, the porous particles typically require treatment such as degassing and drying at temperatures elevated above ambient to maximize their ability to adsorb or be impregnated with the maximum volume of nonflammable gas. Such treatment may also facilitate the subsequent sealing of the gas-filled or impregnated particles.
[0017] The porous particles are filled or impregnated with an inert, flame-retardant gas such as CO 2 , preferably by exposing the prepared particles to the gas in a pressurized (above ambient) environment for a time sufficient to permit the gas to permeate the pores of the particles. Other inert, non-flammable gases such as nitrogen may be appropriate, as well.
[0018] Once the gas is contained or encapsulated within the porosity of the porous particle, the particles may be sealed, preferably with a gas-impermeable polymer such as that disclosed in United States Patent Publication No. 2006-0229402, which is incorporated herein by reference. The preferred sealant must be sufficiently gas-impermeable to be capable of sealing the openings in the porosities against escape of the gas from the porosities and must be applied in such a manner as to seal the gas in the porosities. The sealant must also be chosen to dissolve or degrade under selected conditions (e.g. heat or flame or water) to permit escape of the flame-retardant gas.
[0019] For example, the sealing may occur in an elevated-pressure environment containing the inert gas by dipping or immersing the filled particles in a bath of molten or uncured sealant. Alternatively, the filled particle could be sprayed with the sealant, again preferably in an environment to prevent escape of gas prior to sealing.
[0020] The sealed porous particles may optionally be combined into a matrix, preferably a paint or polymer material, such as polyethylene, polyurethane, polystyrene, or the like. The matrix, if an appropriate (i.e., substantially gas-impermeable) material, may form the sealant, or an additional gas-impermeable sealant may be applied to the gas-impregnated particles prior to dispersion in the matrix. The sealant and matrix also can be varied so as to release the encapsulated gas under different conditions, such as the application of heat or water. Specifically, a heat-reactive matrix containing sealed, gas-containing porous particles is applied to (such as paint) or formed integrally (such as a polymer or plastic) into a substrate so that when the substrate reaches a desired temperature by exposure to heat or flame, the gas is released to extinguish or suppress the nearby flame.
[0021] As noted, in some instances, the matrix itself performs as the sealer. For example, the gas-filled particles are dispersed under conditions that retard escape of gas from the porosities in a polymer in the molten state, the polymer then being formed into an object that has flame-retardant properties. The polymer of the object then seals the porosities of the particle. Clearly, the conditions under which the otherwise unsealed, but gas-impregnated particles are dispersed in the polymer must be controlled to prevent escape of the gas and the polymer of the object must itself degrade upon encountering the selected conditions (heat, flame, water, etc.) to release the gas from the porosities in the particles.
[0022] An example of a flame-retardant application is a flame-retardant fabric., in which sealed, gas-filled or impregnated porous particles are adhered to a fabric such as for clothing Another example of a flame-retardant application is a flame-retardant paint, in which sealed (or unsealed, if the paint contains a polymer or other material suitable for sealing the particles and the particles can be dispersed in the paint without escape of the gas) gas-filled or impregnated porous particles are dispersed in paint. Under these conditions, the binder of the paint can operate as the sealant and the matrix in which the gas-containing zeolites or MOFs are dispersed. Thus, when the paint reaches its decomposition temperature, the gas is released to extinguish or suppress the nearby flame. Alternatively, a sealant separate from the components of the paint can be employed to seal the gas in the zeolite or nanocube. The temperature at which the gas is released then can be based upon the melting or decomposition temperature of the sealant rather than the paint itself.
[0023] Yet another example of a flame-retardant application is a flame-retardant foam. In this application, the foam operates as the matrix for containing the sealed nanocubes, provided the foam is capable of sealing the gas in the porosities of the porous particles. This foam can be a polymeric or hardening foam (like polystyrene or polyurethane) operating primarily as an insulation or cushioning material or a semi-liquid or liquid form that can be dispersed onto fires. Again, the sealant can be the foam itself (in the case of a polymeric foam capable of sealing gas in the porosities of the particles and degrading on encountering selected conditions) or a separate sealant material.
[0024] Still another example of a flame-retardant application is a polymer such as polyethylene or the like in which gas-containing zeolites or MOFs are dispersed. Again, the polymer itself could serve as the sealant or a separate sealant material can be provided to retain the gas in the porosities of the zeolite or nanocube material.
EXAMPLE
[0025] A flame-retardant composition according to the present invention was prepared and tested as follows. The following materials were obtained from the following suppliers:
[0000]
Material
Vendor
Zeolite 5A (molecular sieves, powder)
Sigma-Aldrich
Carbon dioxide gas (high purity,
Olympic Inc. FastHide (latex)
99.99%)
ultra, gloss, white paint
[0026] An appropriate amount of zeolite 5A was degassed at 300C. under vacuum conditions overnight (12 hours) to remove any adsorbates (such as water) from the zeolite. The degassed zeolite was then cooled to room temperature under a vacuum. Carbon dioxide gas was then introduced into a flask containing the degassed zeolite for 5 hours at a pressure of 800 torr. It is estimated that approximately 10% by weight of carbon dioxide was adsorbed by the degassed zeolite 5A (for commercial production, higher pressures and different exposure times may be employed to impregnate more of the inert gas more quickly). The degassed zeolite with carbon dioxide was mixed with a quantity of the paint.
[0027] Three different 2×10 inch papers were prepared and painted as follows: Sample S1 contained only paint without zeolite; sample S2 contained 25% by weight of degassed (as above) zeolite without CO 2 ; and sample S3 was prepared with 25% by weight of CO 2 adsorbed zeolite (as above). Lastly, sample S4 was prepared the same way as sample S3 except the samples were left on a shelf under ambient conditions at room temperature for three weeks.
[0028] Each sample was tested with a flame propagation tester. The papers painted with only paint (S1) and with 25% by weight zeolite 5A without CO 2 (S2) burned within several seconds. However, carbon dioxide adsorbed zeolite 5A added samples (S3) showed drastic retardation of the flame and the fire was extinguished under the sample experimental condition. It is clear that carbon dioxide released from the zeolite at elevated temperatures in the presence of flame retards and extinguishes the fire.
[0029] To investigate the long-term stability of CO 2 adsorbed zeolite containing paint, the S4 samples were kept at room temperature under ambient conditions for 3 weeks as described above. S4 samples produced the same results as S3 samples, i.e., all of the S4 samples extinguished the fire upon burning.
[0030] In this example, the latex contained in the paint operated as a sealant for the porous particles. Also, the CO 2 was not impregnated in the to porosities at very high pressure, nor was particular care exercised in dispersing the particles in the paint. It is believed that impregnation at higher pressures, together with dispersal of the particles under impregnation pressures may result in even better results.
[0031] Having thus described the present invention by reference to certain of its preferred embodiments, it is noted that the embodiments disclosed are illustrative rather than limiting in nature and that a wide range of variations, modifications, changes, and substitutions are contemplated in the foregoing disclosure and, in some instances, some features of the present invention may be employed without a corresponding use of the other features. Many such variations and modifications may be considered obvious and desirable by those skilled in the art based upon a review of the foregoing description of preferred embodiments. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention. | A flame-retardant composition has a plurality of particles with at least one porosity therein, a flame retardant gas occupying the porosity, and a matrix material in which said particles are dispersed. A sealant applied to at least a portion of the particles, wherein the sealant substantially prevents the gas from escaping the porosities. The matrix is a flame-retardant composition adapted to be applied to various surfaces. The matrix may also function as the sealant. The sealant is formed of a material that will break down and release the gas in the presence of water or flame or other selected conditions. The sealant may be a polymer material. This solves the problem of applying flame-retardant qualities to various surfaces. | 3 |
This is a Divisional of application Ser. No. 08/174,919, filed Dec. 29, 1993, now U.S. Pat. No. 5,425,756, which is a Divisional of application Ser. No. 07/888,492, filed May 27, 1992, now U.S. Pat. No. 5,314,462.
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to implantable defibrillation and pacing leads and more particularly to devices of this type which employ fixation structure operative to engage and draw tissue laterally toward the distal end of the defibrillation or pacing lead.
The instant fixation devices are appropriate for minimally invasive defibrillation and use with new, deployable defibrillation leads which are implanted without the currently practiced thoracotomy procedures. The implantation of these leads requires making a small incision in the chest to gain access to the pericardial space. The defibrillation leads are then threaded through the incision and into the pericardial space either alone or through the lumen of a thin walled guiding catheter. Once initially placed in his fashion, a deployment action is performed to expand the surface area of the lead. At this point, the lead is generally held against the myocardial surface by the pericardium.
Because of the lubricious conditions which exist within that space, and the need to more precisely position the leads for defibrillation, lead fixation is required. Fixation to the pericardial sack is the safest approach since it completely avoids accidental laceration of the myocardial circulation. For additional safety, the instant fixation device utilizes hooks that penetrate through the pericardium and return to the lead. These designs do not leave a sharp, pointed object imbedded in the tissue. Still further, the fixation means needs to be robust in order to remain effective through the violent contractions experienced by the heart during initial defibrillation testing. Also, the ability to control device fixation using only simple axial, back-and-forth, "camera cable release-like" motions on common, off-the-shelf devices such as guidewires and stylets is highly desired. This is due, in part, to the fact that the lead may be partially or completely deployed and that lead body rotation and traction due to the remoteness of the insertion site may not be useful technique at this stage of the implant. It also should be noted that although the instant focus is pericardial fixation, these same fixation concepts can be applied to myocardial tissue if knowledge of the local circulation is accurate.
2. Description of Related Art
Various different forms of implantable and internally deployable defibrillation electrodes heretofore have been provided as well as hook and screw-type fixation devices for electro-catheters.
An internally deployable defibrillator electrode is disclosed in U.S. Pat. No. 4,860,760, but does not include structure for fixation prior to or subsequent to deployment of the electrode. U.S. Pat. No. 4,567,900 also discloses an internally deployable defibrillator electrode, but here again also is absent fixation structure.
U.S. Pat. No. 4,624,265 employs both rotary hook and rotary screw fixation devices for an electro-catheter, but rotary hook and rotary screw fixation devices which must be actuated by rotary torque applied at the proximal end of the electro-catheter are objectionable and, this patent does not disclose rotary hook or screw fixation devices which may be utilized in conjunction with an internally deployable defibrillator electrode.
U.S. Pat. No. 3,814,104 describes a pacemaker-lead which attaches to endocardial tissue by means of two gently curved hooks advanced from the lead by means of axial force applied by an internal stylet. The essentially straight hooks provide some degree of fixation but can allow the lead to be simply pulled from the tissue. Also, a special separate flexible catheter is required to force the hooks together if the device needs to be repositioned.
It is felt that the violent contraction of the heart which results from a defibrillation shock may cause the dislodgement of this or any easily removable lead. The need for additional, special hardware for repositioning is also unattractive.
U.S. Pat. No. 4,058,128 describes a pacemaker lead which attaches to the myocardium by means of a single, completely exposed barbed hook. At implant, a significant chest incision is performed to expose the pericardial surface, the lead is grasped with a special grasping tool, both the lead and grasping tool are introduced through the relatively large incision (compared to the lead body itself), the barbed hook is inserted into the myocardial tissue and the grasping tool is removed. In the event that repositioning is required, reintroduction of the grasper is necessary to reverse and then repeat the process.
It is felt that the surgical incision, and the need to introduce a grasping tool into the body, fail to adhere to the concept of a minimally invasive lead. Furthermore, a barb feature on this or any hook may also cause local tissue damage as a result of the violent contraction following the delivery of a defibrillation shock. Accidental laceration of the myocardial circulation is avoided, however, by undesired direct visual inspection of the implant through the large incision.
U.S. Pat. No. 4,013,690 describes a complex self-suturing, endocardial pacemaker lead and a special integral handle-stylet device permanently accompanying the lead from the time of manufacture. After the lead has been implanted using routine surgical technique, the handle activates the ejection of a thin, malleable wire through a distal tubular die and into the tissue. If the acute performance of the lead is satisfactory, the wire suture is broken at a predetermined separation point by means of rotation of the handle and the handle-stylet is removed. Any attempt the reposition this lead after this point would not be possible.
It is felt that this technology fails completely to provide a means to reverse the implant procedure and reposition the lead. Further, the violent contraction at defibrillation testing may weaken if not break the soft, malleable suture wire. Still further, as with '690, special and complex hardware is needed to accompany this lead.
U.S. Pat. No. 4,142,530 describes an epicardial pacemaker lead which is once again implanted through a significant incision in the patient's chest. Once positioned against the epicardium, the lead body is simultaneously pulled along and pressed onto the surface of the heart in order to engage the tissue in at least two curved pointed electrodes. This implantation requires the combination of lead retraction and compression by the surgeon. The means by which the compressive force is applied to the lead head is unclear. A straight, forward anchor is then activated by advancing a stylet against an internal feature of the anchor. This forward anchor generates a force which directs the curved electrodes against the tissue. A nylon wire is attached to the anchor to provide a means for the surgeon to retract the anchor.
It is felt that significant surgery would be necessary to implant such a device. Precise positioning of the electrode on the myocardium through a small incision may be difficult. Also, placement of a lead on the-posterior side of the heart may be impossible. Accidental laceration of the myocardial circulation by either the pointed electrodes or the anchor feature seems likely. The presence of the nylon wire would slightly increase the dimensions of the lead body. This wire becomes an unused, and unnecessary component remaining in the lead and therefore in the patient after the implant.
U.S. Pat. No. 4,233,992 discloses an endocardial electrode with a deployable helical hook. A provision is made to include a barb on these hooks. These leads are implanted using routine surgical technique. The first embodiment employs a non-reversible triggering element to deploy the hook. The second embodiment is deployed by means of a conically tipped stylet. Engagement of the heart tissue is accomplished by the application of external torque on the lead body by the surgeon.
It is felt that these devices fail to provide a means to reverse the implant procedure to accomplish repositioning or removal. Once either hook has been deployed, repositioning of the lead can be significantly hampered. Also, use of a barb may tear myocardial tissue due the contraction of the heart during defibrillation testing.
U.S. Pat. No. 4,357,946 teaches about an epicardial pacemaker lead which is to be implanted during thoracic surgery. Deployment of the helical screw fixation device is accomplished by means of rotation imparted by a stylet while the electrode head is in some fashion held upon the epicardial surface through an external force.
As with '128 and '530 above, it is felt that this technology fails to provide a device which can be implanted through a small incision. Moreover, a rotation action applied to the proximal end of a slim stylet is required to activate the fixation screw. The means to apply an external force to the lead head is unclear.
U.S. Pat. No. 4,378,023 discloses a percutaneously implanted myocardial electrode which blindly penetrates the myocardium to a significant depth. Fixation hooks are released within the myocardial tissue itself. External rotation is necessary to further deploy the fixation hooks. External traction is necessary to set the hooks into the tissue in at least one design.
It is felt that this technology fails on numerous counts. As with '530, precise placement of the electrode on the heart especially placement on posterior regions would be difficult if not impossible. Undesirable rotation of the lead to deploy the fixation hooks is required. Lead repositioning or removal would be extremely difficult. One embodiment in particular would require advancing the lead further into the myocardium to unset the hooks. Such a technique is completely blind and invites potentially lethal perforation of the heart.
U.S. Pat. No. 4,649,938 discloses an endocardial stimulating electrode which is implanted by means of routine surgical technique and requires the use of external rotation of the lead body to advance and attach helical screw to the tissue. Once fixed to the tissue, the spring-loaded helical screw holds the tissue in close proximity to the electrode.
It is felt that this technology fails to accomplish the goals of the instant invention because of the necessity to rotate the entire lead body to engage the tissue. Also, the combination of this undesirable lead body rotation and application of axial force to overcome the spring bias complicates the implant procedure.
U.S. Pat. No. 4,858,623 discloses an endocardial pacemaker lead which deploys a simple spring loaded hook from the lead by means of an axial force applied to an internal stylet. Once deployed, the lead engages tissue following application of external rotation imparted to the lead body. If repositioning is necessary, the stylet is further advanced to locate the hook in its most distal position. The lead is then pulled free of the tissue by simple traction.
If is felt that this technology fails to accomplish the goals of the instant invention because lead body rotation is necessary to attach the lead to the tissue. Also, as with '104, the ease of tissue disengagement by means of simple traction is an undesirable characteristic of a defibrillation lead.
SUMMARY OF THE INVENTION
The defibrillator electrode or electro-catheter of the instant invention is specifically designed for use as an internal defibrillator electrode, but also may be used as a pacing lead.
The instant invention incorporates fixation structure which is effective to hook engage adjacent tissue and to draw the adjacent tissue laterally into engagement with that portion of the electro-catheter from which the hook is supported, whether the fixation structure is carried by the distal end of the electro-catheter or an intermediate length portion of the electro-catheter.
The main object of this invention is to provide an electro-catheter which may be positioned using routine implant techniques including the use of an internal stylet or an outer tubular catheter, each of which being withdrawable to effect deployment of a resilient deformable distal end electrode of predetermined shape.
Another object of this invention is to provide an implantable and internally deployable defibrillation electrode including fixation structure which may be used to effect fixation of the electrode prior to internal deployment of the electrode.
Still another object of this invention is to provide an implantable and internally deployable defibrillation electrode including fixation structure which will allow for fixation of the deployable distal end of the electrode subsequent to deployment thereof.
Yet another important object of this invention is to provide an implantable defibrillation electrode fixation structure which may be actuated and deactuated merely through the utilization of a fixation stylet.
A further important object of this invention is to provide an implantable defibrillation electrode including fixation structure operative to engage adjacent tissue and to draw the distal end of the defibrillation electrode laterally into engagement with the engaged tissue.
Another important object of this invention is to provide an implantable defibrillation electrode including fixation structure which may be actuated by longitudinal force as opposed to rotary torque.
Still another object of this invention is to provide an implantable defibrillation electrode in accordance with the preceding object and incorporating a spring loading mechanism wherein the spring biasing action thereof accomplishes the fixation action and is more readily operable to release and subsequently reestablish fixation in the event it is desired to shift the positioning of a deployed defibrillation electrode subsequent to initial fixation thereof.
A final object of this invention to be specifically enumerated herein is to provide an implantable defibrillation electrode in accordance with the preceding objects and which will conform to conventional forms of manufacture, be of simple construction and easy to use so as to provide a device that will be economically feasible, long-lasting and relatively trouble free in operation.
These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic fragmentary enlarged longitudinal vertical sectional view of the distal end of a deployable implantable defibrillation electrode constructed in accordance with the present invention and with the fixation structure thereof in a spring biased retracted position in solid lines and a partially extended position in phantom lines;
FIG. 2 is a schematic plan view of a first form of the deployed defibrillation electrode utilizing the fixation structure of FIG. 1;
FIG. 3 is a schematic plan view of a second form implantable defibrillation electrode in a deployed condition and wherein the fixation structure of FIG. 1 is incorporated in an intermediate length portion of the electrode at the proximal end of the deployable distal end;
FIG. 4 is a side elevational view of a modified form of implantable defibrillation electrode fixation structure with portions of the tubular body of the electrode broken away and illustrated in section, the fixation hook thereof being in a retracted, shielded condition;
FIG. 4A is a distal end view of the structure illustrated in FIG. 4 with alternate positions of the fixation hook shown in phantom lines;
FIG. 4B is a fragmentary elevational view similar to FIG. 4 with the fixation hook being disposed in a fully extended position;
FIG. 5 is a schematic fragmentary enlarged longitudinal vertical sectional view similar to FIG. 1, but illustrating a third form of fixation device;
FIG. 6 is a fragmentary top plan view of the fixation device shown in FIG. 5;
FIG. 7 is a fragmentary top plan view similar to FIG. 6, but illustrating a double hook form of the device shown in FIG. 6.; and
FIG. 8 is a schematic fragmentary enlarged longitudinal vertical sectional view similar to FIG. 5, but illustrating fifth form of fixation device incorporating a reverse swingable hook.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now more specifically to FIGS. 1 and 2 of the drawings, there may be seen an internally deployable electro-catheter referred to in general by the reference numeral 10 employing a deployable distal end portion 12 and a proximal end portion 14.
The distal end portion 12, in FIG. 2, is illustrated in its deployed pre-configured flag zig-zag shape, the entire length of the electro-catheter being flexible and the distal end portion 12 being capable of being straightened either through the use of an internal straightening stylet inserted thereinto from the proximal end portion 14 or an external flexible tubular catheter (not shown) of greater stiffness than the distal end portion 12.
The precise electrical construction of the deployable end portion 12 may be of any suitable well known type. Suffice it to say that through leads extending the length of the electro-catheter, electrical energy is delivered from a pulse generator to the cardiac tissue of the patient via the conductive distal end portion 12 of the structure.
The terminal distal end 16 comprises a dielectric (biocompatible polymer) tubular housing 19 and defines an endwise outwardly opening cylindrical cavity 18 into which the distal end 20 of a helical tubular spring 22 extending through the distal end portion 12 projects, the proximal end (not shown) of the spring 22 being anchored relative to the proximal end portion 14 in any convenient manner. The distal end 20 includes a stretchable diametrically enlarged portion 24 disposed within the cavity 18 terminating in a diametrically reduced terminal end 26 also disposed within the cavity 18. The portion 24 comprises axial thrust developing means for yieldingly biasing the terminal end 26 in one direction.
The base end 28 of a reverse turned spring hook 30 is anchored to the terminal end 26 of the spring 22 and includes a reversed turned hook 30 on its free end 32 substantially fully contained within the cavity 18.
After the electro-catheter has been inserted and positioned generally as desired for example the electro-catheter being inserted through the utilization of a tubular catheter, a fixation stylet (see FIG. 4B) is associated with the proximal end portion 14 and inserted through the electro-catheter 10 for engagement with the interior of the terminal end 26 of the spring 22 in which the base end 28 of the spring hook 30 is anchored. The fixation stylet thereafter is actuated against the terminal end 26 in a fashion similar to a camera cable release to force the latter toward the open end of the cavity 18 to and past the phantom line position thereof illustrated in FIG. 1 thus expanding the large diameter end portion 24 of the spring 22. Displacement of the terminal end 26 past the phantom line position of FIG. 1 projects the bend 23 of the reversed turned hook 32 from the open end of the cavity 18 for lateral displacement therefrom and engagement of the free end 32 thereof with the tissue to which the terminal distal end 16 is to be fixed. Then, the fixation stylet is released to enable retraction of the hook 30 from the phantom line position thereof to the solid line position thereof to thereby draw the exterior of the terminal distal end 16 laterally into tight contact with the tissue engaged by the hook 30.
Thereafter, the fixation stylet may be removed and the tubular catheter may be withdrawn from about the deployable end portion 12 to thereby enable the latter to deploy and assume the pre-configured shape thereof illustrated in FIG. 2.
With attention now invited more specifically to FIG. 3, a modified form of electro-catheter is referred to in general by the reference 10' incorporating a deployable distal end portion 12' and a proximal end portion 14'. The electro-catheter 10' is of a design to be inserted through the utilization of a tubular catheter and the deployable distal end portion 12' thereof is in the form of a flat spiral coil.
The electro-catheter 10' incorporates a tubular housing 19' corresponding to the tubular housing 19 defining the cavity 18. The housing 19' is serially disposed within the electro-catheter 10' between the proximal end portion 14' thereof and the deployable distal end portion 12' thereof. The internal structure of the housing 19' is substantially identical to the internal structure of the housing 19 in that a helical tubular spring 22' corresponding to the spring 22 has its distal end 20' projecting into the cavity 18' of the housing 19' and the base end 28' of a spring hook 30' corresponding to the spring hook 30 is anchored in the terminal end 26' of the distal end 20', the distal end 20' including an enlarged diameter end portion 24' corresponding to the end portion 24.
The distal end portion 12' is, however, provided with a slot 29 through which the free end 32' of the spring hook 30' may be extended upon utilization of a fixation stylet, for example, of the camera shutter cable release type herein above referred to. Accordingly, the housing 19' of the electro-catheter 10' may be laterally anchored to suitable internal tissues through the utilization of a fixation stylet. In this manner, an intermediate portion of the electro-catheter 10' can be affixed to body tissue after the distal active end of the electrode is permitted to deploy into the pre-configured shape illustrated in FIG. 3.
With attention now invited to FIGS. 4, 4A and 4B, there may be seen a terminal distal end 16" of an electro-catheter 10" which may be considered as substantially identical to the electro-catheter 10, except for the terminal distal end 16" thereof.
The electro-catheter 10" includes an internal coil spring 22" corresponding to the spring 20 equipped with a distal end 20" incorporating an enlarged diameter end portion 24" and a terminal end 26", all of which are enclosed with a housing 19", the distal terminal end of the housing 19" being hollow and frusto conical as at 21 and provided with a partial spiral slot 23. The terminal distal end of housing 19" is open as at 25 on its minor diameter end and the terminal end 26" is projectable through the open end 25 and includes an end enlargement 27 which is retractable only partly into the open end 25.
The terminal end 26" has the base end of a curved hook 33 anchored thereto and the hook 33 projects outwardly through and is slidably received within the slot 23, the slot 23 extending less than 180 degrees about the terminal distal end 21.
The housing 19" may comprise the terminal distal end of an electro-catheter such as the electro-catheter 10 in lieu of the terminal distal end 19 thereof. The electro-catheter 10" would be designed for insertion in the same manner as the electro-catheter 10 and fixed in the desired position prior to deployment of the deployable distal end portion 12" of the electro-catheter 10" corresponding to the deployable distal end portion 12.
In order to affix the terminal distal end 16", after the electro-catheter 10" has been positioned utilizing routine implant techniques such as a tubular delivery catheter, a fixation stylet 17, is inserted into the electro-catheter 10" and associated with the proximal end portion thereof. Then, the fixation stylet is operated in a fashion similar to a camera cable release to lengthwise elongate the enlarged diameter end portion 24" from the condition thereof illustrated in FIG. 4 to the expanded condition thereof illustrated in FIG. 4B, which movement causes the hook 33 to move from the end 37 of the slot 23 in which the hook 33 is retracted to the end 39 of the slot 23, in which position the hook 33 is fully extended, the terminal end 26" being projected through the open end 25 of the terminal distal end 21. Thereafter, the fixation stylet may be released so that the spring biasing action of the enlarged diameter end portion 24" may retract the hook 33 back through the slot 23 from the end 39 thereof to the end 37 thereof, during which movement the hook 33 engages adjacent tissue and laterally draws the terminal distal end 21 toward and against that tissue and simultaneously draws the sharp point 33' into the outwardly opening recess 45 shown in FIG. 4.
After fixation of the electro-catheter 10", the tubular delivery catheter (not shown) may be withdrawn to thereby allow the distal end portion 12" to deploy and assume the pre-configured shape of the distal end portion 12 illustrated in FIG. 2.
The housings 19, 19' and 19" are insulated from the electrical conductors (not shown) which bring electrical energy to conductive outer surface portions of the distal end portions 12, 12' and 12". Further, the phantom lines 41 and 41' indicate the structure of the distal end portions 12 and 12', respectively, which comprise the spiral conductors disposed thereabout and which bring electrical energy to the outer surface portions of the end portions 12 and 12' (the electricity being supplied thereto through proximal lumen tubing or possible bilumen tubing with one lumen incorporating the electrical conductor leading to the conductors and the second lumen dedicated to operation of the fixation device). When the hook 33 is disposed in the end 37 of the slot 23 (subsequent to release of engagement of the hook 33 with organ tissue), it is positioned immediately forward of the shield 45 to thereby facilitate repositioning or removal of the electro-catheter 10" subsequent to its usage.
With attention now invited more specifically to FIGS. 5 and 6, the numeral 110 generally designates an internally deployable electro-catheter similar to the electro-catheter illustrated in FIGS. 1 and 2. All components of the catheter 110 corresponding to similar components of the catheter 10 are referred by similar reference numerals in the one hundred series. Distal end portion 112 includes a dielectric tubular housing 119 in which the distal end 120 of a helical tubular spring 122 is disposed. The distal end 120 includes a strengthable diametrically enlarged portion 124 disposed within a hollow cavity 118 formed in the housing 119 and the diametrically enlarged portion 124 terminates in a diametrically reduced terminal end 126 to which there is secured one end 127 of a thrust rod 129 through the utilization of a suitable fastener 121. The other end of the rod 129 has one end one 131 of a curved hook 133 pivotally secured thereto as at 135 and the free end of the hook 133 is pointed as at 137. The free end portion of the hook 131 projects through a radial opening 139 formed in the housing 119 and extending longitudinally thereof, the housing 119 including cam surfaces 141 and 143 at the proximal and distal ends, respectively, of the opening or slot 139.
The diametrically reduced terminal end 126 and the rod 129 may be advanced toward the rounded distal end 145 of the housing 19 in the same manner in which the terminal end 26 may be advanced from the solid line position thereof in FIG. 1 to the phantom line position thereof illustrated in FIG. 1.
When the rod 129 is in the retracted solid line position thereof illustrated in FIG. 5, the hook 133 is fully retracted and has its pointed end 137 received within an outwardly opening notch 147 formed in one side of the distal end 145 of the housing 119. However, when the diametrically reduced portion 126 and the rod 129 are advanced toward the distal end 145, the cam surface 143 swings the hook 133 in a counterclockwise direction as viewed in FIG. 5 toward the lowermost extended position thereof illustrated in phantom lines. At this point, the housing 119 is positioned adjacent the pericardial sack and the diametrically reduced end portion 126 and the rod 129 are then allowed to retract toward the proximal end of the housing 119 where upon the hook 133 will hook engage the pericardial sack and swing toward the solid line position of the hook illustrated in FIG. 5 thereby fixing the housing 119 to the pericardial sack.
FIG. 6 illustrates the single hook 133 of the electro-catheter 110 illustrated in FIG. 5 and FIG. 7 illustrates a further modified form of electro-catheter 210 which is substantially identical to the electro-catheter 10, except that the electro-catheter 210 includes a pair of hooks or hook members 233 and a pair of recesses 247 in which to receive the free pointed ends of the hook members 233. In addition, the housing 219 of the electro-catheter 210 includes a pair radial openings or slots 239 through which the hooks or hook members 233 operate.
The use two hooks 233 as opposed to a single hook 133 merely provides additional assurance against dislodgement of the fixation device.
Of course, the fixation devices illustrated in FIGS. 5-7 may be incorporated either at the distal end of a deployable defibrillator end portion such as the end portion 12, or at the proximal end of a deployable end portion such as the end portion 12' illustrated in FIG. 3.
With attention now invited more specifically to FIG. 8, there may be seen yet a another form of deployable electro-catheter referred to in general by the reference numeral 310 including a deployable distal end portion 312. The deployable end portion 312 supports a tubular housing 319 therefrom including a radial slot or opening 339 terminating at cam surfaces 341 and 343 corresponding to the surfaces 141 and 143 and a rod 329 is reciprocal within the housing 319 corresponding to the rod 129 and has a hook or hook member 333 pivotally mounted from the distal end thereof as at 335. The rod 329 is yieldingly biased toward the distal end 345 of the housing 319 by a compression spring 349 and retracted away from the distal end 345 by a pull cord or the like 351. During movement of the rod 329 from the solid line position thereof to a position retracted fully away from the distal end portion 345, the hook 333 is cammed by the cam surface 341 to the phantom line position thereof illustrated in FIG. 8, and when the spring 349 is allowed to shift the rod 329 toward the distal end portion 345, the hook 333 is pivoted from the phantom line position thereof illustrated in FIG. 8 to the solid line position thereof. Of course, all of the fixation devices 110, 210 and 310 may be used on either the distal end portion 12 of the distal end portion 12'.
The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention. | An implantable defibrillation electrode including a conductive distal end portion and a non-conductive proximal end portion is provided with at least a major portion of the length of the distal end portion having a pre-configured shape and being resiliently deformable into a generally straight condition. The distal end portion includes distal and proximal ends and at least one of those ends is hollow and has hook structure shiftably supported therein for movement longitudinally thereof from a retracted position at least substantially contained within the hollow end and an extended position at least substantially fully outwardly projected from the hollow end. Spring structure is provided for yieldingly biasing the hook structure from the extended position toward the retracted position and axial thrust developing structure is slidingly telescoped through the proximal end portion and operatively associated with the hook structure for exerting an axial thrust thereon from the terminal end of the proximal end portion in order to effect shifting of the hook structure from the retracted position to the extended position. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to an energy efficient hot water heater system, and more particularly to a hot water heating system having a first low capacity tank for intermittent heating requirements and a second larger tank for periodic heavy demand heating requirements.
It is generally accepted that a water heater is normally the second largest household energy consumer; normal living patterns in typical American households consume significant quantities of hot water each day. For example, it has been estimated that a family of four uses an average of 100 gallons of hot water per day. The operation of the modern automatic clothes washer consumes from 10-18 gallons of hot water for each load of clothing that it handles, and a typical automatic dishwasher uses 8-14 gallons of hot water each day. The use of a bathtub requires 10-15 gallons of hot water, and a shower requires from 8-12 gallons of hot water. The typical hot water heater in an American home is a tank having a 30-40 gallon capacity, and normal usage requirements result in the heating and replacing of the entire tank volume from three to four times per day. Hot water heaters are typically designed to maintain water temperature at a temperature of 120° F. 130° F., and prior art hot water heaters required the entire water tank capacity to be heated to this temperature for 24 hours per day.
The amount of normal heat loss from a hot water tank ranges from 25-35 percent of the heat capacity of the water stored within the tank. This typically increases the cost of operation of the hot water system up to 35 percent, because of the additional heat which must be applied to the system in order to maintain the water temperature at a desired setting even during periods of nonuse. A simple timing mechanism attached to a conventional hot water heater which limits the heating cycle to roughly 12 hours per day, and which permits the water temperature to gradually cool during the off cycle time of the water heater, will itself reduce significantly the energy consumption of a hot water system. However, this approach suffers the disadvantage that, since the heating system is totally disabled during approximately one half the day, the system is incapable of adequately providing for intermittent hot water demand during the off-cycle time.
The present invention overcomes this problem by providing for intermittent heating demand needs while preserving the maximum heating capacity for periodic heavy demand intervals.
SUMMARY OF THE INVENTION
The invention comprises a first hot water tank of relatively low volume capacity, operable under thermostatic control to provide intermittent demand heating requirements; a second larger volume capacity heating tank operable under a timed thermostatic control to provide a reserve of tepid water and to provide a full volume capacity of hot water during heavy demand time intervals. In an alternative embodiment of the invention, an automatic or manual demand override is provided to meet non-predicted heavy uses of hot water, and to cause the larger hot water tank to provide supplementary heating during such periods.
It is a principal object of the present invention to provide a hot water heating system having a first capacity for intermittent heating needs, and a second capacity for periodic heavy demand needs.
It is a further object of the present invention to provide a reserve supply of warm water which may be relatively quickly elevated in temperature to meet intermittent demand needs.
It is another object of the present invention to provide a hot water heating system to meet both intermittent and heavy demand heating needs with a minimum loss of heating energy.
BRIEF DESCRIPTION OF THE DRAWINGS
The aforementioned and other objects of the invention will be understood from the following detailed description of the invention, and with reference to the appended drawings, in which:
FIG. 1 shows a symbolic diagram of the invention; and
FIG. 2 is a graph showing the operation of the invention; and
FIG. 3 shows the timing and thermostatic mechanism.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring first to FIG. 1, there is shown a hot water heating system 10 in symbolic and schematic illustration. A first hot water tank 12 has a capacity of about 10 gallons, and a second hot water tank 14 has a capacity of about 30 gallons. A first heater 13 provides heat energy for heating the water in tank 12, and a second heater 15 provides heat energy for heating the water in tank 14. Heaters 13 and 15 may be gas or oil burners, electric heating elements, or any other conventional form of heater. For purposes of illustration and explanation herein they are referred to as gas-operated heating elements.
A cold water inlet pipe 20 provides a supply of water to tank 14, which is received from conventional water systems such as a well or water main. The temperature of the water provided by inlet pipe 20 is typically in the range of 45-60° F. A coupling water pipe 22 interconnects tanks 14 and 12, serving as a warm water outlet from tank 14 and a cold water inlet to tank 12. A hot water outlet pipe 24 is connected to tank 12, and may be connected to all of the hot water pipes within the structure of interest. In all cases, the direction of water flow through the system is as shown by the arrows.
The supply of fuel into heater 13 is controlled by a valve 16, and the supply of fuel into heater 15 is controlled by a valve 18. Valves 16 and 18 are conventional in design, commonly connected to a fuel line 19 which, by way of example, may be a natural gas line.
The operation of valve 16 is controlled by a thermostat 26 which senses the temperature of the water inside of tank 12. A control line 27 is connected between thermostat 26 and valve 16, which control line 27 energizes valve 16 to provide fuel to heater 13 at a preset lower temperature setting of thermostat 26, and deenergizes valve 16 to shut off the flow of fuel to heater 13 at a preset upper temperature limit of thermostat 26. Thermostat 26 may typically be operated in the range of 120° F.-130° F., with an upper limit of about 160° F., although it is preferable that thermostat 26 be manually adjustable to any desired water temperature in the range of 110° F.-160° F. The combination of thermostat 26 and valve 16 may be similar to the conventional water heater control system found in prior art water heaters.
The supply of fuel to burner 15 is controlled by valve 18, which is in turn controlled by a signal on line 35 or line 29, Line 29 is energized and deenergized by control box 30, which contains conventional switches and a clock mechanism. A thermostat 32 is electrically connected to control box 30 by line 33; a thermostat 34 is connected to valve 18 by line 35. Thermostats 32 and 34 respectively sense the water temperature within tank 14, and each of them may be preset to become activated over predetermined temperature ranges. For example, thermostat 32 may be set to provide a first signal on line 33 at a water temperature of about 130° F., and to provide a second signal at a water temperature of about 110° F. Thermostat 34 may be set to provide a first signal on line 35 at a water temperature of about 110° F., and a second signal at a water temperature of about 70° F. The thermostat control signal on line 33 is regulated by a clock timer in control box 30, so as to permit thermostat 32 to be connected in control relationship to line 29. Control box 30 therefore permits an elevated temperature thermostatic control to operate tank 14 during a predetermined time interval.
An alternative and override signal may be provided by means of line 36. Line 36 becomes energized at a predetermined low temperature setting of thermostat 26, and when energized causes an override signal to couple thermostat 32 directly to line 29, bypassing the clock timer. In this manner, line 36 may be used to detect heavy demand from tank 12, which demand causes the temperature of water in tank 12 to drop below a predetermined limit, and to thereby override the normal control sequence for tank 14 to cause tank 14 to immediately begin heating to supplement the water in tank 12. The components used in control box 30 may be of conventional design, and may include switches and clock timers which are readily available in the industrial control field.
A manual override signal may be provided by means of switch 37, which may be manually activated to couple thermostat 32 directly to line 29, thereby bypassing the clock timer.
FIG. 3 shows the timing and thermostatic mechanism in symbolic and schematic form. A conventional alternating current power source is coupled to control box 30 via lines 50 and 51. This power is used to operate the clock timing mechanism as well as to energize valve 18 as will hereinafter be described. Thermostat 32 is connected to line 50 through normally closed switch contacts 53. Switch contacts 53 are opened at a predetermined temperature within tank 14 by control bellows 54, which operates against spring 55. Knob 56 may be adjusted to vary the spring force of spring 55, and thereby to control to temperature of tank 14 at which switch contacts 53 open. When switch contacts 53 are closed the voltage on line 50 is applied to line 33 and thereby to control box 30.
Line 33 is internally connected in control box 30 through the parallel combination of switch 37, timer switch 58, and timer switch 60, to line 29. Thus line 29 becomes energized with the voltage of line 50 whenever the thermostatic switch contacts 53 are closed, and any of the following additional events occur:
a. manual switch 37 is activated;
b. timer switch 58 is activated; or
c. timer switch 60 is activated. Timer switches 58 and 60 may be activated by setting appropriate "on" and "off" tabs at selected time intervals in a manner which is conventional with timing devices of this type.
FIG. 2 illustrates a graph showing the typical timing operation of the invention. The horizontal axis of FIG. 2 is representative of time, and may represent a typical 24 hour day. The vertical axis of FIG. 2 is representative of temperature, and may represent typically the temperature of 0° F.-160° F. Line 26a represents the relatively constant temperature "Z" which is provided to the water within tank 12 by thermostat 26. Under normal use conditions thermostat 26 will maintain the temperature of the water in tank 12 at a temperature "Z", which may be for example in the range of 120° F.-130° F. Line 40 represents the typical temperature conditions in tank 14 at different times during a 24 hour period. Tank 14 is initially controlled at a temperature "X", provided by thermostat 34, which temperature may be in the range of 70° F.-100° F. At a preset time "A", control box 30 switches thermostat 32 into a controlling relationship to valve 18, thereby permitting tank 14 to begin heating to the higher temperature setting "Y" of thermostat 32. The temperature of tank 14 remains under the control of thermostat 32, typically at about 110° F.-130° F., until time "B", which is presumed to be the end of the peak demand for hot water from the system. At time "B" and thereafter, control box 30 switches thermostat 32 out of controlling relationship to valve 18, and thereby back to the lower temperature thermostat, permitting the temperature within tank 14 to gradually become lowered to temperature "X". At time "C" the cycle again repeats itself and control box 30 again switches to the higher temperature thermostat 32. This higher temperature control setting continues until time "D", at which time it again returns to the control of the lower temperature thermostat 34. The temperature cycling of tank 14 is illustrated to occur twice during each 24 hour period, although other and further combinations of thermostatic coupling could be achieved by proper selection of the timing mechanism within control box 30. However, it is known that in a typical residential home the hot water demands peak during the early morning wake up hours and again peak during the early evening hours, and it is therefore believed that the operational embodiment described herein is preferred for most uses.
The apparatus shown in FIG. 1 may be enclosed in a cylindrical cover having suitable insulation around tanks 12 and 14 to minimize heat loss therefrom. The burned fuel from heaters 13 and 15 may be collected in a conventional manner by means of a smoke stack which may be mounted above the housing enclosing tanks 12 and 14.
In operation, thermostat 26 is set to the desired hot water temperature setting to be delivered by the system. The timer in control box 30 is adjusted to provide elevated temperature control of tank 14 during the presumed peak demand intervals. Thermostats 32 and 34 are each set for a low temperature warming setting and a higher temperature peak load setting. The preferable low temperature setting is in the range of 70° F.-110° F., and the preferable higher temperature setting for tank 14 is about 120° F. The presumed peak demand periods may be between the hours of 6:00 A.M. and 9:00 A.M., and 5:00 P.M.-7:00 P.M. The timing mechanism within control box 30 should be set to permit heater 15 to turn on early enough to provide peak demand hot water from tank 14 during the actual peak demand hours.
The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore desired that the present embodiment be considered in all respects as illustrative and not restrictive, reference being made to the appended claims rather than to the foregoing description to indicate the scope of the invention. | Apparatus is disclosed for heating hot water in separate tank stages, and according to predetermined cyclic time patterns. A first smaller hot water tank is heated to a first elevated temperature under thermostatic control, and a second larger hot water tank is heated to a second lower temperature under thermostatic control and to a third elevated temperature under thermostatic control during a predetermined time cycle; provision is made for demand override of the heating mechanism of the second tank. | 5 |
BACKGROUND OF THE INVENTION
It is now prevalent in satellite microwave communications systems for such systems to process multiple channels. This requires the combination or separation of the channels either for transmission or for processing after acquisition. This function is usually accomplished by means of a multiplexer.
The typical multiplexer consists of a series of input waveguides generally including filter elements connected to a waveguide manifold through ports or iris'Each of the filters is tuned and the iris' designed for maximum efficiency of the overall system. The connections of the input waveguides to the manifolds must be accurately positioned according to strict spacing requirements governed by the wavelength (λ) of the transmitted microwave energy. The spacing is measured along the longitudinal axis of the manifold from the shorted end.
The spacing requirements are often difficult to meet because of manufacturing tolerances. Prior art systems, however, provide no means by which spacing inaccuracies can be adjusted after the parts of the multiplexer are constructed and assembled. It is a purpose of this invention to provide a means to adjust the manifold spacing.
In order to obtain optimum performance of the multiplexer, while minimizing losses, the internal impedance of the various components must be closely matched. This process of tuning the system requires the balancing of hundreds of variables many of which are extremely sensitive because of the high frequency environment. The design of these components has, therefore, become a difficult technological challenge.
Although the optimization problem can be diminished through the use of various design techniques, precise construction of the components is made difficult, if not impossible by the inherent limitations of manufacturing tolerances. The design of the these components, therefore, ultimately relies on a trial and error process in which multiplexers are constructed, tested, modified, retested and gradually optimized. There are limits however, to the number of iterations which can be employed with constructive results.
It is therefore desirable to provide additional methods of tuning a manifold. It is therefore a purpose of this invention to provide a method of simulating manifold spacing adjustment by deforming the manifold dimensions to change the wavelength and assist in the tuning of the overall system.
SUMMARY OF THE INVENTION
The manifold of this invention is constructed with a primary manifold section to which the input wave guides, including filters, are connected. One end of the manifold is shorted and the other is open to form an output port. The filter couplings are spaced along the longitudinal axis of the manifold a predetermined distance from the shorted end of the manifold. A series of tuning brackets are mounted on the manifold at positions between the input waveguide/filter couplings. These brackets constrain the manifold and are constructed with adjustment screws extending through the brackets and mechanically connected to the manifold. The screws engage the bracket by means of threads to enable the screw to be adjusted in and out of the bracket. The movement of the adjustment screw will tend to deform the manifold dimensions resulting in a fine adjustment of the guide wavelength (λ) of the multiplexer. In affect this change in the microwave characteristics of the manifold acts as a spatial adjustment of the position of the input wave guides.
DESCRIPTION OF THE DRAWING
The invention is described in more detail below with reference to the attached drawing in which:
FIG. 1 is a schematic diagram of the multiplexer of this invention;
FIG. 2 is a cross sectional view of the tuning bracket of this invention;
FIG. 3 is a graph showing the relationship of waveguide wavelength (λ) with waveguide dimensions and frequency; and
FIG. 4 is a graph showing the relationship between changes in waveguide wavelength relative to adjustments in waveguide width.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The system of this invention is constructed for use in a satellite communications network in which multiple channels are required. In the process of receiving and transmitting microwave signals, either at a ground station or on board an orbiting satellite, it is necessary to combine or separate the communication channels before further processing. This task is accomplished by means of a multiplexer. For illustration purposes an output multiplexer 1 is described with particular reference to FIG. 1 . In this particular application the channeled output of the multiplexer 1 is fed to an antenna for transmission to a ground station.
Since it is intended for use onboard a satellite, the system must be accurately tuned because there is no opportunity for further correction after it is in orbit. The multiplexer 1 is an assembly of several waveguides 2 - 4 with waveguide cavity filters 15 - 17 which are coupled to the manifold 5 , as shown in FIG. 1 . Each of the input waveguides 2 - 4 receive microwave signals through an input port 14 and are coupled to the manifold 5 by an appropriate coupling mechanism 22 , as is known in the art. The waveguides 2 - 4 will generally be coupled through filters 15 , 16 and 17 . The filters may be provided with tuning screws 10 as used in the prior art.
The manifold 5 is constructed having a primary section 7 enclosing a waveguide 6 . The primary section has shorting cap 18 at one end and an output 8 at the other end. The primary section 7 may be constructed of an appropriate lightweight, high strength material having the necessary conductivity characteristics such as silver plated carbon reinforced composite or a temperature stable alloy such as is sold under the trademark INVAR. In addition the waveguide can be constructed from the walled aluminum sheet. In general the manifold is constructed with a rectangular cross section having a broad wall 24 at the top, side walls 25 , and a bottom wall 26 .
The input waveguides 2 - 4 are positioned along the longitudinal dimension of the manifold at distances x,y, and z respectively from the short 18 . The wavelength of the waveguide is chosen from the middle of the waveguide band. The general practice is to start by spacing the input waveguides at distances of half wavelengths and then adjust in plus or minus increments. It follows that the distances from the short 18 will be multiples of half wavelengths at least at the start. According to this invention a method and apparatus are provided which effectively adjusts the dimensions X, Y, and Z electrically by small changes in the width (w) of the waveguide.
In accordance with this invention, a series of tuning brackets 9 , 11 , and 12 are mounted on waveguide 7 at predetermined locations, between each of the input waveguides 2 - 4 and between the waveguide 3 and the short 18 . In order to obtain maximum effectiveness of the adjustment the brackets are placed midway between the incoming waveguides as shown in FIG. 1 . Brackets 9 , 11 , 12 are restrained from movement on the waveguide by means of angle members 19 and 21 held in place by screws 20 . An adjustment screw 13 extends through the bracket and is operatively connected to manifold 7 through a pad 11 fixed to manifold 7 . The screw may be operated to apply a deformation force 22 , either in compression or tension, to the short side 23 of the manifold 7 . This serves to adjust the width (w) at the manifold in small increments on the order of 0.001 inches.
The overall system 1 of this invention is tuned to optimize the performance of the multiplexer while minimizing losses. The design is performed taking into consideration the many variables in accordance with the trial and error practices currently in use. In order to tune the multiplexer of the subject invention, the adjustment screw 13 is moved in and out by applying an appropriate torque. This will deform the manifold width (w) sufficiently to change the characteristic wavelength of the manifold. Since the spacing of the input components of the multiplexer 1 is dependent on the wavelength, this adjustment by deformation has the effect of adjusting the spacing between the input components. This adjustment allows a fine tuning of the multiplexer 1 beyond currently available design methods.
As shown in FIG. 4, the adjustment of the width of the manifold will change the on/off frequency of the waveguide λ C which is equal to 2w. The waveguide (λ Y ) will change in accordance with the formula λ Y =λ O / (1−λO 2 /λ O 2 )½. In this manner a simple and reliable mechanism is provided to tune the multiplexer of the assembly. | A series of tuning brackets are mounted on the microwave waveguide manifold at positions between the input waveguide/filter couplings. These brackets constrain the manifold and are constructed with adjustment screws extending through the brackets and mechanically connected to the manifold. The movement of the adjustment screw will tend to deform the manifold dimensions resulting in a fine adjustment of the wavelength (λ) of the multiplexer. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of application Ser. No. 60/889,098, filed Feb. 9, 2007, under 35 U.S.C. §119(e).
BACKGROUND OF INVENTION
1. Field of Invention
The present invention relates generally to caps for drinking vessels.
2. Description of Related Art
Alcoholic beverages, and particularly mixed beverages, are often served in public restaurants, nightclubs, taverns and bars in open top drinking vessels (e.g., bar glasses and stemware). The uncovered opening of such drinking vessels makes it easy for the bar tender to prepare the beverage. However, the uncovered opening also makes it possible for depraved individuals to add an incapacitating substance such as Rohypnol, for example, to a patron's beverage when they are not closely guarding the drinking vessel (e.g., while conversing with another, dancing etc.).
BRIEF SUMMARY OF THE INVENTION
In view of the foregoing, the present invention is directed to a cap for covering the open top of a drinking vessel. The cap according to the invention comprises a substantially rigid cover disk assembly dimensioned to span across and substantially cover the open top of the drinking vessel, and a flexible tubular membrane that extends from a bottom side of the cover disk assembly. The membrane is adapted to be rolled down a side wall of the drinking vessel to thereby removably secure the cap thereto. Identifying indicia can be printed on the top side of the cover disk assembly. The beverage within the drinking vessel can be consumed using a drinking straw. When properly deployed, the cap inhibits the introduction of unwanted matter into the drinking vessel.
The foregoing and other features of the invention are hereinafter more fully described and particularly pointed out in the claims, the following description setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principles of the present invention may be employed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a top plan view of a cap for a drinking vessel according to one embodiment of the invention.
FIG. 2 is a bottom plan view of the cap shown in FIG. 1 .
FIG. 3 is a side section view of the cap shown in FIG. 1 taken along the line 3 - 3 .
FIG. 4 is a bottom perspective view of the cap shown in FIG. 1 .
FIG. 5 is a perspective view of the cap shown in FIG. 1 deployed on a drinking vessel.
FIG. 6 is a perspective view of a package containing a cap such as shown in FIG. 1 .
FIG. 7 is a side section view of a cap in which the upper disk portion and the lower disk portion have co-extensive perimeter edges.
DETAILED DESCRIPTION OF THE INVENTION
With reference to the accompanying figures, a cap 10 according to the invention comprises a substantially rigid cover disk assembly 20 having a flexible tubular membrane 30 secured thereto and extending therefrom. The tubular membrane 30 is adapted to be stretched so as to extend around and thus entirely surround and envelope an open-top portion of a drinking vessel 40 such as, for example, a pilsner glass, a pint glass, a cocktail glass, a highball glass or other tumbler, a wine glass or other stemware, or a “pop-top” beverage can. The tubular membrane 30 is also adapted to be unrolled down an outer side wall 50 of the drinking vessel 40 such that the cover disk assembly 20 substantially covers the open top of the drinking vessel 40 .
The cover disk assembly 20 is preferably formed of an upper disk portion 60 and a lower disk portion 70 , which are joined together with a first end portion 80 of the tubular membrane 30 captured therebetween. The upper disk portion 60 and the lower disk portion 70 are preferably joined together using a suitable adhesive. Alternatively, and less desirably, mechanical fasteners such as staples can be used to join the upper disk portion 60 and the lower disk portion 70 together.
The upper disk portion 60 is preferably formed of a compressed cellulosic material such as paperboard, which may be faced with a thin layer or film of paper or plastic. A top side 90 of the upper disk portion 60 can be printed with decorative and/or informative indicia 100 such as, for example, advertising for products and/or services. The indicia can also be provided on the upper disk portion 60 through the use of adhesive stickers. Preferably, markings can easily be applied to the top side 90 of the upper disk portion 60 using an ink pen or pencil, which allows a patron to further personalize and uniquely identify their beverage.
The lower disk portion 70 is preferably formed of a moisture resistant material such as plastic. Moisture resistant materials are preferred because beverage contents can splash upwardly against the bottom side 110 of the lower disk portion 70 . It will be appreciated that the upper disk portion 60 and/or the lower disk portion 70 could be formed of a variety of different materials (e.g., paperboard, light metals, plastics, wood and/or laminates comprising two or more thereof) to form a substantially rigid cover disk assembly 20 .
The thickness of the cover disk assembly 20 is not critical, but a thickness within the range of from about 1/16″ (˜1.6 mm) to about ¼″ (˜6.5 mm) is generally believed to be sufficient. In the presently most preferred embodiment of the invention, the cover disk assembly 20 is formed of a flat paperboard upper disk portion 60 having a thickness of about 3/32″ (˜2.4 mm) that is joined to a flat plastic lower disk portion 70 having a thickness of about 1/16″ (˜1.6 mm) using an adhesive.
The upper disk portion 60 is provided with a first opening 120 through which an end of a drinking straw 130 can be inserted. The first opening 120 is preferably circular in shape and has an inner diameter that is slightly larger than the outer diameter of the drinking straw 130 . It will be appreciated that the shape of the first opening 120 is not critical.
The lower disk portion 70 is provided with a second opening 140 through which the end of the drinking straw 130 can be inserted. The second opening 140 preferably comprises a plurality of intersecting slits 150 , which thus form flaps 160 that bias against the drinking straw 130 when the drinking straw 130 is inserted through the second opening 140 . The flaps 160 allow the lower disk portion 70 to remain in contact with the drinking straw 130 after the drinking straw 130 has been inserted through the second opening 140 , which minimizes any open area between the drinking straw 130 and the lower disk portion 70 . It will be appreciated that the number of slits and corresponding flaps is not per se critical.
In the embodiment of the invention shown in FIGS. 1-4 , the second opening 140 through the lower disk portion 70 comprises a pair of intersecting slits 150 , which intersect at about a 90° angle and thus form four flaps 160 that bias against the drinking straw 130 when the drinking straw passes through the second opening 140 . In this embodiment, the slits are provided in a circular recessed area 170 . The recessed area 170 reduces the thickness of the lower disk portion 70 , which allows the flaps 160 to flex more than if the flaps 160 were thicker, and also helps prevent the slits 150 from tearing beyond the area defined by the recessed area 170 . The recessed area 170 also facilitates proper alignment of the upper disk portion 60 with the lower disk portion 70 when the same are joined together. It will be appreciated that an inverse arrangement could be utilized for the first opening and the second opening (i.e., the first opening would include intersecting slits whereas the second opening would be dimensioned sufficiently large enough to allow a drinking straw to pass therethrough).
The upper disk portion 60 has a first perimeter edge portion 180 . In the embodiment shown in the accompanying figures, the first perimeter edge portion 180 defines a circle. However, it will be appreciated that the shape defined by the first perimeter edge portion 180 is not critical, and that shapes other than circles can be used. For example, the first perimeter edge portion 180 may be adapted to define a polygon, the border of one or more US States, the border of one or more countries, animal and plant shapes or the shape of advertising logos. Although the shape defined by the first perimeter edge portion 180 is not critical, the first perimeter edge portion 180 of the upper disk portion should define a shape sufficiently large to substantially cover the entire opening of a drinking vessel 40 on which the cap 10 is deployed.
The lower disk portion 70 has a second perimeter edge portion 190 . Preferably, the second perimeter edge portion 190 does not include any points or angles that could pierce or cut the tubular membrane 30 that extends around the second perimeter edge portion 190 . Thus, the second perimeter edge portion 190 preferably defines a circle, an oval or some other shape having rounded corners. In the most preferred embodiment of the invention, the second perimeter edge portion 190 of the lower disk portion 70 defines a shape that is just slightly larger than the shape of the open-top portion of the drinking vessel 40 onto which the cap 10 is to be deployed. As used in this context, the term “slightly larger” means that the second perimeter edge portion 190 of the lower disk portion 70 extends no more than about ¼″ (˜6.4 mm) beyond the rim or top edge of the drinking vessel 40 .
It will be appreciated that the upper disk portion 60 needs to be at least the same size as the lower disk portion 70 . FIG. 7 shows a section view of a cap 10 wherein the upper disk portion 60 has a first perimeter edge 180 , wherein the lower disk portion 70 has a second perimeter edge 190 , and wherein the first perimeter edge 180 is co-extensive with the second perimeter edge 190 . More preferably, the upper disk portion 60 is larger than the lower disk portion 70 , meaning that the first perimeter edge portion 180 of the upper disk portion 60 is spaced apart from the second perimeter edge portion 190 of the lower disk portion 70 . In the preferred embodiment of the invention illustrated in FIG. 3 , the first perimeter edge portion 180 of the upper disk portion 60 is spaced apart about ¼″ (˜6.4 mm) from the second perimeter edge portion 190 of the lower disk portion 70 .
The tubular membrane 30 is preferably formed of a stretchy, resilient, flexible material such as a thin film of natural latex rubber, silicone or a polyurethane elastomer. In the preferred embodiment, the membrane 30 is fluid impermeable. Natural latex rubber having a thickness similar to that used in the manufacture of surgical gloves is particularly preferred.
As noted, the first end portion 80 of the tubular membrane 30 is captured between the upper disk portion 60 and the lower disk portion 70 . Preferably, the adhesive used to join the upper disk portion 60 and the lower disk portion 70 together also helps secure the first end portion 80 of the tubular membrane 30 to the cover disk assembly 20 . The second end portion 200 of the tubular membrane 30 preferably defines a ring, which facilitates rolling the tubular membrane 30 upwardly toward the lower disk portion 70 .
The tubular membrane 30 is selectively displaceable from a first position to a second position. In the first position, which is shown in FIGS. 1-4 , the tubular membrane 30 is rolled about the ring disposed at the second end portion 200 upwardly toward the lower disk portion 70 . In the second position, which is shown in FIG. 5 , the tubular membrane 30 is unrolled to cover and surround the outer side wall 50 of a drinking vessel 40 and thereby form skirting 210 . The flexible, elastic properties of the tubular membrane 30 cause the skirting 210 to conform to and closely surround the outer side wall 50 of the drinking vessel 40 . When completely unrolled, the skirting 210 preferable has a height “H” of about 2.5″ (˜6.4 cm) to about 4.5″ (˜11.4 cm).
The cap 10 according to the invention can be packaged in a pouch 220 or other suitable protective enclosure prior to use. Optionally, the pouch can further contain a drinking straw 130 , which may be a telescoping drinking straw. The tubular membrane 30 should be in the first position when placed in the pouch 220 . The pouch 220 containing the cap 10 according to the invention can be kept in a pocketbook or garment pocket until needed. It will be appreciated that the pouch 220 can be imprinted with advertising indicia, making it particularly suitable for use as a promotional product. A variety of sizes of caps 10 can be produced and inventoried for use with drinking vessels having openings of varying size.
To use the cap according to the invention, a patron or beverage preparer first removes the cap from its protective pouch. The cap is placed onto a drinking vessel containing the beverage. With the tubular membrane in the first position, the cap is placed onto the open-top portion of the drinking vessel such that the lower disk portion is in contact with or nearly in contact with the top portion of the drinking vessel (e.g., the rim or the top of a beverage can). The rolled-up tubular membrane is then grasped and stretched and pulled down around the outer perimeter of the drinking vessel until the lower disk portion of the cover disk assembly adequately covers the open top portion of the drinking vessel. Next, the tubular membrane is unrolled down around the outer side wall of the drinking vessel, thereby surrounding the outer side wall of the drinking vessel with the skirt portion of the tubular membrane as shown in FIG. 5 . If desired, an easy-to-tear, tamper-evident adhesive label 230 can be applied to secure the second end portion of the tubular membrane to the outer side wall of the drinking vessel. A drinking straw is then inserted through the first opening through the upper disk portion and the second opening through the lower disk portion of the cover disk assembly.
Once deployed, the cap prevents unwanted matter (e.g., insects and drugs) from entering the drinking vessel. The cap inhibits would-be criminals and others from adding unwanted substances to the beverage contained within the drinking vessel. It takes time for a person to unroll, remove, and then redeploy the cap onto a drinking vessel. Furthermore, removing the cap from a drink is a conspicuous act. Finally, in the event that a tamper-proof label has been applied to secure the tubular membrane to the outer side wall of the drinking vessel, removal of the cap from the drinking vessel will be evident.
It will be appreciated that the deployed cap also helps to minimize spills and broken glassware. The skirt portion of the membrane provides a comfortable non-slip gripping surface.
Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and illustrative examples shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents. | The present invention provides a cap for covering the open top of a drinking vessel. The cap includes a substantially rigid cover disk assembly dimensioned to span across and substantially cover the open top of the drinking vessel, and a flexible tubular membrane that extends from a bottom side of the cover disk assembly. The membrane is adapted to be rolled down a side wall of the drinking vessel to thereby removably secure the cap thereto. Identifying indicia can be printed on the top side of the cover disk assembly. The beverage within the drinking vessel can be consumed using a drinking straw. When properly deployed, the cap inhibits the introduction of unwanted matter into the drinking vessel. | 1 |
CROSS REFERENCE TO RELATED PATENTS AND APPLICATIONS
This application is a Continuation-in-Part of Ser. No. 08/572,638, filed Dec. 14, 1995, now abandoned.
BACKGROUND OF THE INVENTION AND PRIOR ART
This invention relates in general to exercise equipment and in particular to a low impact exercise device that simulates a full range of natural striding motion including aggressive striding. It also relates to a striding exercise device that is useful in performing upper body workouts.
The prior art includes a great number of exercise devices that simulate walking, a form of low muscle stress exercise that nearly everyone can perform. The beneficial effects achievable by walking are in proportion to the effort expended. The well known treadmill exercise machine exemplifies such apparatus.
Recently a variety of exercise devices that impose low or minimal impact on the user's knees and legs have become popular. While such devices generally provide some aerobic benefit, they often constrain the user's legs into a very unnatural locked-knee position. In such devices, the user stands on swingably mounted platforms that, for safety reasons, are interlocked to prevent both platforms from simultaneously moving in the same direction. While the interlocking reduces the danger of the user being placed in a precarious position, it unnaturally constrains the user's arm and leg motions and precludes long, natural, as well as aggressive, striding movements.
Handles that are linked to the foot platforms, either directly or indirectly, assist the user in maintaining balance. Even so, the combined foot and arm movements of the devices rarely simulate a natural striding motion. While a treadmill does simulate walking, it imposes impact loading on the user's body, especially on the knees and legs. For many users, this impact loading is undesirable and may even be detrimental.
The prior art also includes a number of so-called cross country skiing machines which attempt to simulate the body movements of a cross country skier. While such machines can provide a very strenuous low impact workout for the user, they are difficult to master, requiring a degree of user skill and balance similar to the sport itself.
The prior art devices generally constrain the range of movement to a small safety zone to preclude the user getting into an unbalanced and precarious position. The limited movements permitted in these devices do not allow for a long, natural striding motion, much less aggressive striding motions, nor do they enable any significant weight transfer to the arms, which is necessary to obtain an upper body workout.
With the exercise device of the present invention, a full range of striding motion is very closely simulated while impact on the user's body is practically eliminated. Significantly, the aerobic effect experienced is readily controllable by merely accelerating the striding action and lengthening the stride, precisely as can be done when aggressively striding. However, unlike striding, with the inventive device a user can lean backward and forward to transfer significant weight to his arms without loss of balance or control. This not only increases the aerobic effort and enables an upper body workout, but also varies the muscle groups that are being exercised.
The inventive device is very comfortable and easy to learn and use, imparting a feeling of balance and stability to even the most novice of users. It also readily accommodates users of different strength and agility. Further, different muscles may be exercised by elevating on one's toes, bending one's knees or by grasping different portions of the handles. The handles move integrally with the foot platforms, in a natural manner, without requiring any linkage or interconnection between the handles or between the foot platforms, which are independently swingable.
OBJECTS OF THE INVENTION
A principal object of the invention is to provide a low impact exercise device that simulates natural and aggressive striding.
Another object of the invention is to provide a novel exercise device that simulates striding and enables safe upper body workouts.
A further object of the invention is to provide a low impact striding exercise device that is safe, comfortable and easy to learn and use.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other objects and advantages of the invention will become apparent upon reading the following description in conjunction with the drawings, in which:
FIG. 1 is a side elevation of one version of the exercise device of the invention;
FIG. 2 is an enlarged side elevation of the exercise device;
FIG. 3 is an enlarged front elevation of the exercise device;
FIG. 4 is a plan view of the exercise device shown in FIG. 3;
FIG. 5 is an enlarged partial cross sectional view taken along line 5--5 of FIG. 4;
FIG. 6 is an end view of the structure of FIG. 5;
FIG. 7 is a perspective view of another version of the exercise device;
FIG. 8 is a reduced side elevation of the exercise device of FIG. 7, illustrating a long striding position;
FIG. 9 is a front elevation of the exercise device illustrated in FIG. 8; and
FIG. 10 is an enlarged partial cross sectional view taken along line 10--10 of FIG. 9.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawings generally and in particular to FIGS. 1-4, a user is shown exercising on one version of the striding device 10 of the invention. A generally square base 12 includes side members 12a and 12b, a front member 12c and a rear member 12d. The side members 12a and 12b include short stubs 12e that engage and laterally support four vertical uprights 14, 15, 16 and 17. The frame members are fabricated from tubular steel with the various junctions between members being preferably welded. The stubs 12e are provided to enable the frame to be partially disassembled for convenient shipping.
A pair of front support hinge tubes 36 and 37, defining a front hinge axis, are supported by end rings that are secured to the tops or ends of the uprights, preferably by welding. Thus, a front hinge axis is defined by the end rings 18 and 19 that are secured to the ends of uprights 14 and 15, respectively. Similarly a pair of rear support hinge tubes 38 and 39, defining a rear hinge axis, are supported by end rings 20 and 21 that are secured to the ends of uprights 16 and 17 (not shown), respectively.
A pair of flat, generally rectangular rigid foot platforms 26 and 27 is suspended from the front and rear support hinge tubes by a pair of linkages, respectively. Right foot platform 26 is pivotably supported at its front by a pivot pin 28 that engages a right front linkage 22 and at its rear by a pivot pin 30 that engages a right rear linkage 24. Similarly, the front of a left foot platform 27 engages a left front linkage 23 by a pivot pin 29 and the rear of the platform engages a left rear linkage 25 by a pivot pin 31. The front linkages 22 and 23 are outwardly bowed to provide knee clearance for those users who exercise vigorously by taking long aggressive strides while bending their knees. The rear linkages 24 and 25 are similarly outwardly bowed to permit hip swinging movements without interference. A pair of handles 34 and 35 extend outwardly and upwardly at an angle from the front of the exercise device 10 and a pair of foot stops 30 and 31 is secured to the tops of the foot platforms 26 and 27, respectively, near their forward ends.
With particular reference to FIGS. 3 and 4, handles 34 and 35 are seen to be affixed to the pair of front support hinge tubes 36 and 37, that are in turn affixed to front linkages 22 and 23, respectively. Hinge tubes 36 and 37 are rotatably mounted on a front bearing tube 40 (shown in FIGS. 5 and 6) that extends between end rings 18 and 19. The front bearing tube 40 serves as an axle for the front support hinge tubes. Rear support hinge tubes 38 and 39 are similarly rotatably mounted on a rear bearing tube (not shown) that extends between end rings 20 and 21, respectively. The front and rear support hinge tubes are thus centered about the front and rear hinge axes that extend between the respective pairs of front and rear end rings as discussed above.
In the partial views of FIGS. 5 and 6, portions of front support hinge tubes 36 and 37 are shown, it being understood that front support hinge tube 37 is a mirror image of hinge tube 36. As mentioned, end ring 18 is welded to the top of upright 14 and receives the end of bearing tube 40 therein. The bearing tube 40 is secured in end ring 18 (and in end ring 19 at its other end) by a roll pin 18a that is inserted in aligned holes in the end ring 18 and the end of bearing tube 40. A pair of T bushings 36a and 36b support front support hinge tube 36 for rotatable motion about bearing tube 40. A similar arrangement is used for front support hinge tube 37 and its T bushings, only one of which (37a) is shown. The T bushings are preferably made of molded nylon and have appropriate diameter shoulders for securing them in the ends of the hinge tubes. The arrangement provides thrust bearing surfaces between the end rings and the T bushings, between the facing surfaces of T bushings 36a and 36b and between the front support hinge tubes and the bearing tube. It will, of course, be recognized that the bearing tubes may be replaced by solid axles should that be desired.
The front and rear bearing tubes provide rigid bridges between the front uprights 14 and 15 and between the rear uprights 16 and 17, respectively. The front linkages 22 and 23 and the rear linkages 24 and 25 are spaced apart on their respective bearing tubes a distance that matches the spacing of an average person's feet. This configuration applies tension loading through linkages 22, 23, 24 and 25 and compression loading on the uprights 14, 15, 16 and 17.
Referring to FIGS. 1 and 2, some important aspects of the inventive device will be noted. The frame design, with its spaced apart uprights and its axes defined by front and rear supports, produces a stable structure with easy entry from either side. It will be noted that the foot platforms and the linkages depart slightly from a parallelogram shape. Specifically, the distance D1 between the end rings 18 and 20 is somewhat less than the distance D2 between the foot platform pivot pins 29 and 30. Also the height of the hinge axes defined by the front and rear pairs of end rings is chosen to match the swing radius of a person's leg, generally about hip high. This arrangement establishes a "zone of stability" for the user. So long as the center of mass of the user stays within the zone of stability, the user is not placed in a precarious position with respect to the machine, despite the fact that the foot platforms (or handles) are not interlinked in any way. The arrangement enables the user a great deal of freedom of movement in performing exercises, including very long natural and aggressive striding movements, and significant shifting of his weight forward or backward to transfer loading to his arms and hands. The solid restraining rails formed by the front and rear bearing tubes and support hinge tubes also provide safety stops should the user's center of mass move outside of the zone of stability while engaging in overly aggressive movements on the machine. It has been found that the zone of stability provides sufficient tolerance so that a machine designed to accommodate a person of average height and weight will enable most people to obtain substantially the full benefits of the invention, namely a long, natural striding motion and significant upper body workout, without losing their balance or being put in a precarious position. A person's weight positively biases the center of mass of the person toward a balance point within this zone of stability. In practice, the distance between end ring 18 and pivot pin is approximately 95 centimeters and that between end rings 18 and 20 is approximately 54 centimeters.
The spacing of the front and rear axes (defined by the front and rear support hinge tubes) results in a flattening of the arc through which the foot platforms travel and enables the user's feet and ankles to bend in a more natural manner. It will also be seen that the rear of each foot platform is slightly higher than its front, as is indicated by the distances D3 and D4, where D4 is greater than D3. This arrangement insures that the user's feet stay firmly in contact with the toe grips, imparts a more rapid heel rise and minimizes any unnatural bending of the ankle at the forward extremity of a long stride.
Another aspect of the invention is the placement of the handles 34 and 35 relative to the user. The handles pivot in front of the user which accommodates a natural arm extension. The handles extend outwards and upwards from their pivot point which accommodates the natural reach of the user relative to height at which the handles are grasped. The handles are also spaced wider apart than the foot platforms for the comfort of the user.
The exercise device of the invention permits very easy entry from either side of the frame. Also the front support hinge tubes 36 and 37 and rear support hinge tubes 38 and 39, in conjunction with the bearing tubes, form sturdy front and rear restraining rails for the security of the user.
In operation, a user enters the exercise device from either side, standing on the foot platforms and placing his feet within the corresponding foot stops. The handles 34 and 35 may be grasped or, alternatively, the user may hold onto the front support hinge tubes 36 and 37. For a mild walking exercise, the user should take short steps. The degree of arm effort is readily controllable and exerting more arm effort diminishes the effort required by the legs and vice versa. The wrists may be exercised in varying degrees by changing the position of the hands on the handles. For true natural striding, long steps are taken, with the degree of aerobic effort required being fully under the control of the user. By leaning forward or backward and by bending the knees or raising upon the toes, different upper and lower body groups of muscles may be exercised in varying degrees. For aggressive striding, very long steps are taken.
FIGS. 7-10 illustrate another version of the invention, in which a pair of spaced apart uprights 58 and 60 are supported on a base having a front crossmember 52 and a rear crossmember 54 connected together by a center member 56 and suitable plates 62 and 64. Front crossmember 52 includes end plates 66 and 68 that support a pair of rollers 70, which are normally not in contact with the floor by virtue of support pads 71 on the underside of the base. The rollers enable easy relocation of the exercise machine by grasping rear crossmember 54 and lifting to transfer the load to the rollers. This arrangement also obviates movement of the machine during strenuous exercises which might otherwise occur if the rollers 70 were in contact with the floor. The various members are formed of tubular steel of rectangular cross section.
A stationary front support tube 82 is welded to the top of front upright 58 and supports an axle (not shown) upon which front support hinge tubes 84 and 86 are rotatably mounted. Suitable end caps 76 cover the ends of the front support hinge tubes. A pair of rigid front linkages 78 and 80 are secured to front support hinge tubes 84 and 86 by means of portions 88 and 90, respectively. The upper ends of the rigid linkages 78 and 80 form handles for a user to grasp. The bearing arrangement for the front support hinge tubes 84 and 86 is similar to that previously described, and include a bearing tube and suitable T bushings.
A longer stationary rear support tube 74 is welded to the top of rear upright 60 and is enclosed by a pair of end pieces 76. A pair of rear flexible linkages, in the form of cables 75 and 77 whose upper ends are partially wrapped around the periphery of support tube 74 and affixed thereto by suitable fasteners 75a and 77a. This construction is best seen in FIG. 10. The cables support the rear ends of the foot platforms. The lower portions of the cables pass over generally circular guides 53 and 55 that are affixed to the rear ends of the foot platforms. The front ends of the foot platforms are pivotally secured to the lower ends of the rigid front linkages 78 and 80 by pivot pins. The cable guides 53 and 55 are preferably molded of high strength plastic.
It will be apparent that during swinging, the rear cables will wrap and unwrap on the support tube 74 and cable guides 55 thus changing its length slightly. As shown, the effects of wrapping on support tube 74 and unwrapping on cable guide 55 tend to offset each other. It will also be seen that cable 75 can be wrapped in a clockwise manner around support tube 74 to alter the effect.
As more clearly shown in FIGS. 8 and 9, a pair of shock absorbers 94 and 96 are provided to increase the resistance experienced by the user and to therefore enable a more aerobic exercise session, if desired. An extension 92 on the front of front upright 58 supports an axle 93 to which one end of each of shock absorbers 94 and 96 is rotatably secured. The other ends of the shock absorbers are rotatably secured to respective ones of the rigid front linkages 78 and 80 by suitable pins 79 and 81, respectively. The shock absorbers may be of conventional design and arranged to be easily disconnected should the user prefer, or they may incorporate user-operable orifice changing mechanisms to vary their resistance. The base of the FIG. 7 version of the invention is bolted together at the plates 62 and 64, which enables the exercise machine to be conveniently shipped, while requiring very simple assembly by the user.
It will be appreciated by those skilled in the art, that the construction of both versions of the invention provide a strong and stable frame for the user. The bushings make for a completely silent exercise device which is of great benefit since a majority of users engage in television viewing or conversation while exercising.
What has been described is a novel exercise device that provides a low impact simulation of walking and striding, including aggressive striding, in addition to enabling both upper and lower muscles groups of the body to be exercised to the degree desired. It is recognized that numerous changes to the described embodiment of the invention will be apparent to those skilled in the art without departing from its true spirit and scope. The invention is to be limited only as defined in the claims. | An exercise device that simulates a striding action includes a base. Four linkages support two independently swingable side-by-side foot platforms from spaced apart front and rear supports secured to uprights that are connected to the base. The front and rear supports are positioned with respect to the foot platforms to substantially match the swing length of a person's leg. The distance between the front and rear supports is less than the distance between the front and rear pivots on the foot platforms. Outwardly extending handles are integral with the foot platforms and are spaced farther apart than the distance between the foot platforms. The rear of each foot platform is slightly elevated with respect to its front. | 0 |
BACKGROUND OF THE INVENTION
The present invention relates to automatic welding devices, and more particularly to a collet for retaining and positioning T-shaped studs adjacent the surface onto which they are to be welded.
In U.S. Pat. No. 3,582,602 issued to Donald H. Ettinger et al. and assigned to the assignee of the present invention, there is shown an automatic portable gun system for repetitively welding relatively small components in the form of T-studs, or buttons, to panel surfaces. In the above cited patent, there is disclosed a welding gun which has a tubular electrode member with a button-holding means at its projecting ends through which buttons are delivered to the holding means for retention during welding. The tubular member disclosed in that device is a relatively heavy-walled metallic member which is machined to provide a collet at the outer end for holding the stud adjacent the workpiece during the welding operation. The collet, as generally provided in such devices, comprises a metallic member which is machined to provide a plurality of close tolerance fingers at the outer end thereof for gripping the button or stud as it is forced into the end of the tubular member, to be held against the work surface.
While these heavy metallic members prove satisfactory in providing a tubular electrode member and chuck, or collet, combination, there are certain drawbacks to this prior art collet arrangement as described in the aforementioned patent.
First, the manufacture of the collet arrangement requires a plurality of machine operations, some of which are to close tolerances in view of the relatively small size stud or button which is used in the automobile industry, for example.
Also, the welding gun is generally provided with an arc shield which surrounds the button at a fixed distance therefrom, in which case the heavy metallic chuck or collet extends very close to the inner dimension of the arc shield providing little clearance therewith. Over a period of time, the large frontal area of the collet collects a buildup of weld material often called "splatter". When a sufficient quantity of this material collects, there may be arcing between the collet and the workpiece which is detrimental to the welding operation.
It is, therefore, an object of the present invention to provide a collet of the type described which is inexpensive and easy to manufacture in contrast to prior art collets.
Another object of the invention is to provide welding apparatus of the type described wherein the frontal surface of the collet is of less area than prior art devices, and therefore minimizes the probability of arcing due to the collection of spatter material on the collet.
SUMMARY OF THE INVENTION
The above objects, as well as other objects which will be apparent as the description proceeds are accomplished by providing an automatic electric welding gun for end welding buttons to a panel with a novel collet comprising a tubular member having an inner end disposed adjacent the feed chamber in the gun and an outer end extending from the wall structure of the gun. The tubular member comprises an internal surface having a larger diameter at the inner end than at the outer end and an internal surface which is of constant diameter for at least a portion of the distance from the outer end to provide an internal surface portion which is substantially normal to a work surface with the periphery of the outer end of the tubular member parallel with the work surface. The collet is generally formed of a unitary sheet of metallic material, such as spring steel, having a range of 0.010"- 0.050" thickness. The collet is also generally provided with a plurality of slots formed at the outer end and extending toward the inner end which may be three in number, including one which extends the entire length of the collet to provide spring action to the entire length of the collet.
BRIEF DESCRIPTION OF THE DRAWING
For a more complete understanding of the invention reference should be made to the accompanying drawing wherein:
FIG. 1 is an elevational view partially in section showing a stud welding device incorporating the teachings of the present invention;
FIG. 2 is a side elevational view partly in section showing an element of the structure of FIG. 1 in detail, taken on an enlarged scale for clarity;
FIG. 3 is a front elevational view showing details of the structure of FIG. 2; and
FIG. 4 is an elevational view partially in section showing the element of FIGS. 2 and 3 in combination with the related structure of FIG. 1.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring to the drawing and in particular to FIG. 1 there is shown an automatic electrode welding gun which, with the exception of those elements which are newly introduced and described herein below, may be similar in construction and operation to that described in U.S. Pat. No. 3,582,602 to Donald H. Ettinger and Englebert A. Meyer assigned to the assignee of the present invention.
As shown in FIG. 1 the welding gun 10 is provided with a collet holder 12, which is fastened to the body structure of the gun 10 by means of a fastener 14. The collet holder 12 has a central bore 16 formed therein which extends through the collet holder and provides an internal opening through which a ram 17 is received. The forward end of the collet holder 12 receives a collet 18 which extends forwardly through an arc shield 20.
The arc shield 20 is supported on the gun 10 by arc shield holder 22 mounted on a quick disconnect 24. The quick disconnect 24 is adapted for receiving a conduit through which the studs to be welded are delivered, one at a time, to the gun. The arc shield 20, as described in the aforementioned U.S. Pat. No. 3,582,602, is an insulative member which may be properly termed both a panel locator and an arc shield. That is to say, the tubular insulating arc shield 20 is both a panel locator and forms a shield preventing arcing between the stud to be welded and adjacent portions of the panel structure, lying outside the shield. The arc shield 20 therefore, is of a somewhat fixed diameter in order to maintain the welding arc within a desired area, defined by the periphery of the shield.
In operation, the stud is delivered through the conduit attached to the quick disconnect 24 and enters a chamber 26 formed in the wall structure of the collet holder 12. The ram 17 contacts the button and pushes it forward into the collet 18 to the outer end of the collet and in contact with the surface to which it is to be welded. The ram 17 also serves to carry the welding current to the button when the button is positioned to the outer end of the collet 18.
As referred to above, the operation of the welding gun 10 is similar to that described in the aforementioned U.S. Pat. No. 3,582,602 and reference may be had to that patent for a better understanding of the control arrangement and welding process.
Referring now to FIGS. 2 and 3, there is shown in detail the collet 18 which is formed of 0.020" thickness 1060 spring steel, but preferably may be in the range of 0.010"- 0.050" in thickness. The collet 18, as shown in FIG. 2, has an inner end 28 of larger diameter than an outer end 30 and a substantially constant diameter portion 31 extends from the inner end toward the outer end over a greater portion of the collet. The wall structure of the collet has a plurality of slots 32, 33 and 34 which extend from the outer end 30 toward the inner end 28. The slot 34 extends over the entire length of the collet 18 and is in effect formed by the edges of the unitary sheet used in forming the collet 18. The slot 34, therefore, provides flexibility over the whole area of the collet and in particular at the inner end of 28 which is received in the bore 16 of the collet holder 12.
At the outer end 30, each of the slots 32, 33 and 34 combine to retain the button head of a fastener B in gripping relation during the welding process, as shown in FIG. 1. The internal diameter of the collet at the outer end 30 being of slightly smaller diameter than the button head of the fastener in the relaxed condition, provides a gripping force on the button, the slots 32, 33 and 34 forming fingers which are resiliently flexible due to the relatively thin resilient sheet material employed in construction of the collet.
In addition to the constant diameter portion 31 of the collet 18, there is a tapered portion 36 terminating at a second constant diameter portion 38 at the outer end 30. The constant diameter portion 38 retains over its entire length the diameter at outer end 30 which is slightly less than a diameter of a button to be welded when the outer end of the collet 18 is in the relaxed or unstressed condition. Thus, the inner surface of the constant diameter portion 38 is normal to the plane of the surface to which the button is to be welded when the button is placed against the work surface and serves to retain the button in such normal position during the welding operation. The portion 38 has the effect of applying pressure over the entire surface of the head of the button to be welded, with the result that when the collet 18 is normal to the work surface, the button will likewise be normal to the work surface.
Adjacent the inner end 28 of the collet 18 there is provided a pair of detents 40 and 42 for retaining the collet 18 in the collet holder 12.
Referring to FIG. 4, it will be noted that the collet holder 12 has a groove 44 formed therein. To install the collet 18 into the collet holder 12, it is merely necessary to pinch the collet such that the detents 40 and 42 are received in the bore 16, and move the collet 18 into the bore until the detents snap into place in the groove 44. Removal of the collet also merely requires pinching the collet until the detents 40 and 42 are released from the groove 44, after which the collet may be removed through the bore 16.
From the foregoing, therefore, it should be evident that the present invention provides a novel collet which is simple and inexpensive to manufacture, easy to install and may be employed in welding guns of the type referred to above.
Additionally, as the diameter of the arc shield 20 is substantially fixed by the size of the button to be employed, the thin wall thickness of the collet produces a small outside collet diameter, and therefore increases the air gap between the collet and arc shield. The result is less splatter build up and a minimum of collet burnout and component failure. The relatively thin walls of the collet 18 also provide a limited front surface area on which buildup of flash material will take place. | An automatic device for feeding and welding T-profile button studs to a surface is provided with a collet for retaining and aligning an individual stud in place adjacent a workpiece. The collet is formed of relatively thin sheet metal and is effective to properly orient the fastener relative to the workpiece surface while minimizing the occurence or arcing in the area between the collet and the arc shield. | 8 |
FIELD OF THE INVENTION
The present invention relates to a sebaceous excitosecretory agent exhibiting a long-lasting excitosecretory action on sebaceous glands.
BACKGROUND OF THE INVENTION
The skin or hair is kept healthy and beautiful by sebum secreted from sebaceous glands. However, the skin gradually loses its smoothness and moistness from adolescence to senescence due to a failure of the sebaceous secretory function, especially in females. For the purpose of supplying oily matters to the skin suffering from a failure of sebaceous secretory function, drugs, medical supplies and cosmetics for oil supply in various forms such as creams, clear lotions and milky lotions, have hitherto been employed.
When conventional products for oil supply are applied to the skin, oily components are of short duration due to gradual removal by external causes such as rubbing although temporarily retained on the skin surface.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a sebaceous excitosecretory agent that has a prolonged action of exciting secretion of sebum and continuously accelerates oil supply to the skin.
Another object of the present invention is to provide a process for exciting secretion of sebum using the above sebaceous excitosecretory agent.
Other objects and effects of the present invention will be apparent from the following description.
The inventors of the present invention have studied various physiologically active substances and found as a result that undecylenic acid excites the function of sebaceous glands and thus completed the present invention.
The present invention relates to a sebaceous excitosecretory agent comprising at least one of undecylenic acid, its salts, its esters, and its amide derivatives as an active ingredient.
The present invention also relates to a process for exiting secretion of sebum comprising the step of applying the above sebaceous excitosecretory agent onto a skin surface.
DETAILED DESCRIPTION OF THE INVENTION
Incorporation of the above-described active ingredient(s) into products for oil supply affords a sebaceous excitosecretory agent having an excitative effect on the sebum secretory function essentially possessed by the human skin as well as the conventional function of oil supply thereby making it possible to supply oily matters to the skin in a natural mode and in a continuous manner.
The sebaceous excitosecretory agent of the present invention also proved effective to improve the skin in the convalescence following senile xeroderma and eszematosis of dry type such as atopic dermatitis.
Undecylenic acid is a fatty acid present in sweat and is known for long to have antimicrobial activity. There has been reported that undecylenic acid is incorporated into shampoos, etc. as an anti-dandruff agent or used as not yet been reported.
Undecylenic acid to be used in the present invention may be in the form of a free acid as well as a salt, an ester or an amide derivative. Examples of the salts of undecylenic acid include potassium, sodium, calcium, magnesium, and zinc salts. Examples of the undecylenic esters include alkyl esters, e.g., methyl, ethyl, propyl, and isopropyl esters; aromatic esters, e.g., benzyl and allyl esters; esters with a polyhydric alcohols, e.g., glycerin, propylene glycol, and polyethylene glycol; and an epoxypropyl ester. Examples of the amide derivatives of undecylenic acid include a monoethanolamide and a diethanolamide. However, the salt, ester or amide derivative of undecylenic acid used in the present invention is not limited to the above examples. The undecylenic acid and derivatives thereof may be used either individually or in combination of two or more thereof.
The sebaceous excitosecretory action of undecylenic acid was investigated according to the following Reference Example.
REFERENCE EXAMPLE
Ten week-old hamsters were divided into three groups each consisting of 4 animals. A first group was maintained on 0.05 ml/animal/day of a 5 wt % solution of undecylenic acid in ethanol applied to the inner side of the auricle for consecutive 14 days. A second group was maintained on 0.05 ml/animal/day of a 1 wt % solution of undecylenic acid in ethanol in the same manner. To a third group (control), ethanol containing no undecylenic acid was administered in the same manner. After 14-day administration, the area of the sebaceous glands in the inner side of the auricle was measured by means of an image analyzer. The results obtained are shown in Table 1 below.
TABLE 1______________________________________ Undecylenic Total Area Acid Number of 100 Concentration of Sebaceous GlandsGroup (wt %) Animals (mm.sup.2)______________________________________1st Group 5 4 4.31 ± 1.002nd Group 1 4 2.56 ± 0.42Control 0 4 1.92 ± 0.18______________________________________
As is apparent from Table 1, undecylenic acid increases sebaceous glands of the auricle in size.
Components of the sebaceous excitosecretory agent other than the above-mentioned active ingredients can be selected from known components.
The sebaceous excitosecretory agent of the present invention may have various dose forms, such as clear lotions, oils, ointments, creams, and milky lotions, according to known techniques.
Undecylenic acid is a fatty acid contained in sweat as stated above and is of no harm to the human body. Therefore, the concentrations of undecylenic acid, its salts, its ester derivatives, and its amide derivatives in these dose forms is not particularly limited and can appropriately be determined according to the dose form as long as the effectiveness of the agent is not adversely affected. The concentration is generally from 0.01 to 10% by weight, and preferably from 0.1 to 5% by weight, based on the total amount of the agent.
If desired, the sebaceous excitosecretory agent of the present invention may further contain other components generally employed in conventional cosmetics as long as the effects of the present invention are not impaired.
The conventional components and its production process as well as the conventional components added thereto of the cosmetic compositions are described, e.g., in Keshohin-Gaku (Cosmetic Science), edited by T. Ikeda, published on May 20, 1979 by Nanzando, Japan, which is incorporated herein by reference, but the present invention is not construed as being limited thereto. Related portions of this reference are shown in the following table.
______________________________________ Compositions and OtherCosmetics production process components______________________________________Lotions page 220, line 14 to page 251, Table 31 page 221, line 12 upCreams page 235, line 9 up to page 227, line 6 up to page 236, line 6 up page 228, line 5Emulsions page 243, line 10 to page 242, line 12 to page 244 line 6 up______________________________________
The sebaceous excitosecretory agent of the present invention can be used in a conventional manner so as to excite secretion of sebum to prevent drying of the skin. For example, the sebaceous excitosecretory agent of the present invention can be applied to dry parts of the skin surface with hands or fingers one or more times a day for the face, or 2 to 4 times a day for hands, legs and other parts. The application amount of the sebaceous excitosecretory agent of the present invention varies depending on the composition and the part to which the agent is applied, and is generally from 0.05 to 1.0 g per 100 cm 2 of skin.
The present invention is now illustrated in greater detail by way of Formulation Examples and Test Example, but it should be understood that the present invention is not deemed to be limited thereto. All the percents are by weight unless otherwise indicated.
______________________________________FORMULATION EXAMPLE 1Clear Lotion______________________________________Zinc undecylenate 0.5%1,3-Butylene glycol 6.0%Ethanol 8.0%Polyoxyethylene hydrogenated castor oil (60 E.O.) 0.8%Methyl p-hydroxybenzoate 0.05%Citric acid 0.05%Sodium citrate 0.07%Perfume 0.1%Purified water balance 100% in total______________________________________
The clear lotion having the above formulation can be used by applying with hands to a dry skin surface of a face, hands, leg and the like several times a day.
______________________________________FORMULATION EXAMPLE 2Oil______________________________________Ethyl undecylenate 0.5%Cholesteryl stearate 1.0%Olive oil 2.0%Squalane balance 100% in total______________________________________
The oil having the above formulation can be used by applying a few drops of the oil to a dry skin surface of a face, hands, legs and the like 1 to several times a day.
______________________________________FORMULATION EXAMPLE 3Cream______________________________________Undecylenic acid 1.0%Bleached bees wax 4.0%Cetanol 2.0%Lanoline 2.0%Liquid paraffin 9.0%Self-emulsifiable glycerol monostearate 3.0%Polyoxyethylene sorbitan monostearate (20 E.O.) 1.5%Propyl p-hydroxybenzoate 0.1%Methyl p-hydroxybenzoate 0.2%1,3-Butylene glycol 5.0%Perfume 0.2%Purified water balance 100% in total______________________________________
The cream having the above formulation can be used by applying to a dry skin surface of a face, hands, legs and the like 1 to 3 times a day.
______________________________________FORMULATION EXAMPLE 4Milky Lotion______________________________________Undecylenic acid monoethanolamide 1.0%Liquid paraffin 5.0%Vaseline 2.0%Bees wax 1.0%Sorbitan sesquioleate 2.0%Polyoxyethylene oleyl ether (20 E.O.) 2.5%Ethyl p-hydroxybenzoate 0.2%1,3-Butylene glycol 5.0%Carboxyvinyl polymer 0.5%Potassium hydroxide 0.3%Perfume 0.2%Purified water balance 100% in total______________________________________
The milky lotion having the above formulation can be used by applying in the similar manner as for the clear lotion.
TEST EXAMPLE
Twenty females ranging in age from 39 to 53 were divided into two groups (10 females per group). 0.1 ml of the cream prepared in Formulation Example 3 was applied to the forehead of a first group once a day for 4 weeks. A control cream having the same composition as the cream except for containing no undecylenic acid was applied to the forehead of a second group in the same manner. After 4 weeks, the applied part was washed with a face cleaner. After standing for 2 hours, cigarette paper (2×3 cm) was attached to the part for 3 hours to collect the sebum secreted on the skin surface. The sebum was extracted from the cigarette paper and weighed. The results obtained are shown in Table 2 below.
TABLE 2______________________________________ Amount of SebumGroup (mg/cm.sup.2 /3 hr)______________________________________1st Group 0.24 ± 0.06Control 0.19 ± 0.05______________________________________
As can be seen from Table 2, the test group maintained on the cream containing undecylenic acid revealed a significant increase of sebum on the surface of the skin.
As described and demonstrated above, the cosmetics for skin care according to the present invention excite the sebaceous secretory function essentially possessed by the human skin and supply oily matters to the skin in a natural and continuous manner to thereby give the skin or hair smoothness and moistness. Further, the sebaceous excitosecretory agent of the present invention is effective to improve skin conditions in the convalescence following eszematosis of dry type such as senile xeroderma and atopic dermatitis.
While the invention has been described in detail and with reference to specific examples 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. | A sebaceous excitosecretory agent comprising at least one of undecylenic acid, its salts, its esters, and its amide derivatives as an active ingredient. A process for exciting secretion of sebum comprising the step of applying onto a skin surface the above sebaceous excitosecretory agent. The sebaceous excitosecretory agent has a long-lasting action to excite secretion of sebum. | 8 |
FIELD OF THE INVENTION
This invention relates to an inflator assembly particularly a propellant filled inflator assembly with a diffuser or endcap attached that provides a safer shipping and storage feature in the event of a fire.
BACKGROUND OF THE INVENTION
Inflation of a typical airbag cushion in a vehicle is achieved by igniting a propellant stored in an inflator. Once ignited, the propellant rapidly generates large volumes of gas which fill the airbag inflating the cushion to protect the vehicle occupants. These devices are credited for saving numerous lives in the event of a vehicle crash.
During the manufacture of these propellant filled inflators, special care is used to insure proper handling and safety precautions are followed to avoid inadvertent ignition of the propellant.
Once assembled, the inflators laden with propellant are moved to an assembly location wherein the inflator can be placed in a module housing along with the airbag cushion. In the case of a side curtain airbag, the inflator may be attached to a fill tube connected to a curtain airbag or directly to the cushion. Alternatively, the inflators could be boxed and stored for later assembly or shipment. In any event, large numbers of the inflators are routinely shipped and transported to vehicle assembly plants.
It is during storage and transportation that these propellant filled inflators can pose a risk in the event of an inadvertent ignition. The situation is generally remote, but in the event of a fire in shipping or storage, the propellant could be ignited causing a release of gases which could cause a condition of high thrust making the unrestrained inflator a projectile or missile causing a risk to personnel standing nearby or those trying to put out the fire.
As a result of this risk, the United States Department of Transportation requires inflators to be subjected to a bonfire test wherein the inflator when placed directly in a fire cannot become a projectile upon ignition of the stored propellant.
To pass this test, inflator manufacturers have devised ways to balance the exhausting gases to create a “thrust neutral” or “zero thrust” inflator.
In U.S. Pat. No. 7,938,443 B a patent entitled “Shipping Safe Inflator For An Airbag Module” discloses a distal end portion of an inflator with a thrust balancing feature having a plurality of elongated secondary apertures with deflection vanes open to exhaust the gases in a thrust balance configuration. This distal end can discharge gases exiting along the axis through the primary discharge opening and the elongated secondary passages redirect part of the flow longitudinally aft oppositely directed to cancel thrust and has a plurality of radially oriented openings to exhaust more of the gas radially in such a fashion the inflator has no thrust capability due to inadvertent ignition.
Others have simply designed inflators with a plurality of holes radially around the circumference of a housing to create a thrust neutral inflator. This technique is most simple and easy to employ in passenger side inflators and other applications wherein the inflator is stored in a housing assembly.
In side curtain airbags, the inflator is generally not in a module housing, but is secured directly onto the vehicle along with the airbag curtain connected via a hose or tubing assembly. In this case, the inflator needed to be designed in such a way that the propellant gases are captured to fill the curtain. Ideally the gases are not lost or vented to atmosphere to achieve a thrust neutral condition when in use. This is true because to vent large amounts of the inflation gases means even more propellant must be used so the remaining captured gases are sufficient to fill the airbag. Accordingly, to insure the inflator achieves a thrust neutral balanced exhaust when exposed to fire during shipping and storage, but when assembled for normal use this safety feature does not waste the inflation gases a new a superior way to manufacture a thrust neutral inflator assembly is needed. Preferably, the new way is accomplished in a cost efficient and very reliable way. These and other beneficial objectives are satisfied by the present inventive design described herein.
SUMMARY OF THE INVENTION
An inflator 30 for producing inflation gas from a propellant 31 has a housing for storing the propellant 31 , a diffuser 10 for attachment to the inflator 30 housing and a sealing member 20 . The diffuser 10 has one or more open passages 14 for passing inflation gas upon ignition of the propellant 31 and a plurality of sealed passages 12 oriented opposite to the one or more open passages 14 . The sealing member 20 covers the sealed passages 12 . The sealing member 20 is consumed when exposed to an open flame thereby opening the sealed passages 12 to vent inflation gases opposite the opposed one or more open passages 14 to create a thrust neutral exhaust upon an inadvertent ignition of the propellant 31 due to exposure to fire. The plurality of sealed passages 12 have an area relative to the area of the opposed one or more open passages 14 of the diffuser 10 balanced in size to ensure thrust neutrality. The sealed passages 12 are four or more openings in the diffuser 10 . The sealed openings 12 are one of circular, square, rectangular, triangular holes or rectangular slots or any combination of these shapes covered by the sealing member 20 .
The sealing member 20 is preferably made of a thermo plastic or elastomeric material. The material from which the sealing member 20 is made is consumed by exposure to flame.
The diffuser 10 is made of metal. The diffuser 10 has an inlet portion of circular cross section 15 having an open inflation channel 1 and the sealing member 20 is attached internally along an arcuate segment of an internal surface 11 of the diffuser 10 . The sealing member 20 has a yield strength, an ultimate strength and a percent elongation set to exceed the inflation pressure and temperatures of the ignited inflator 30 in normal use of inflating an airbag. The sealing member 20 when assembled into the diffuser preferably has at a minimum a yield strength of 33 MPa, ultimate strength of 35 MPa and percent elongation of 50 percent. The sealing member 20 can withstand the maximum inflation pressure and maximum temperature generated by the normally ignited inflator 30 without losing seal integrity in the absence of exposure to external flames or fire related temperatures which are adapted to consume the sealing member 20 exposing the sealed passages 12 . The sealing member 20 when assembled into the diffuser 10 preferably can withstand 2600 psi at 90 degrees C. The sealing member 20 material can be DELRIN 100 NC010, an acetal material.
The sealing member 20 has a plurality of short cylindrical projections 21 adapted to plug the sealed passages 12 ; and wherein two or more of the projections 21 are used to secure the sealing member 20 to the diffuser 10 . Preferably, the two or more projections 21 extending through the openings 12 of the diffuser 10 are heat staked or ultrasonically welded 23 onto the diffuser 10 to secure the sealing member 20 .
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will be described by way of example and with reference to the accompanying drawings in which:
FIG. 1 is a perspective view of the inflator with a thrust neutral diffuser according to the present invention with a plurality of sealed passages sealed by a sealing member.
FIG. 2 is a perspective view of the igniter delay cartridge device of the present invention.
FIG. 3 is a perspective view of the diffuser showing the sealing member attached to the internal surface of the diffuser.
FIG. 4 is a perspective view of the sealing member.
FIG. 5 is perspective view of an alternative construction showing an endcap of the present invention.
FIG. 6 is a view of the present invention inflator with a flame consumable sealing member in the diffuser shown in a side curtain airbag application.
FIG. 7 is a second view of the present invention inflator with a flame consumable sealing member in the diffuser used in a vehicle seat for connection to an inflatable seatbelt.
DETAILED DESCRIPTION OF THE INVENTION
With reference to FIG. 1 , an inflator 30 is shown with a diffuser 10 attached to a discharge end 33 of the inflator 30 . The inflator 30 has a longitudinal shaped housing 32 inside of which is stored a solid propellant 31 for generation of inflation gases for filling an airbag cushion. The propellant 31 is ignited by an ignition device (not shown) that can be activated in the event of a vehicle crash. The overall structure of the inflator 30 can be of any style or shape as long as it has a discharge end 33 to which the diffuser 10 can be securely attached.
As shown, the diffuser 10 has a cylindrical inlet end 15 which surrounds and is secured onto the discharge end 33 of the inflator 30 . Once assembled, the inflator 30 and diffuser 10 become one assembly.
As illustrated in FIG. 2 , the diffuser 10 has a plurality of passages or holes 12 . As shown, the holes 12 are circular openings. Alternatively, the passages or openings 12 can be configured square, triangular, rectangular holes or open slots or any combination of these. Along a 180 degree opposite orientation to the plurality of openings 12 is shown a cylindrical discharge portion 10 A of the diffuser 10 . This discharge portion 10 A has an opening or passageway 14 which is orthogonal to an axis of the inflator 30 and upon ignition of the propellant 31 ; the generated gases are directed into the inlet end 15 of the diffuser 10 along an inlet channel 1 and turned along the passageway 14 which is connected to a tube airbag assembly or directly on an airbag to inflate it.
As shown in FIGS. 1 and 3 , the plurality of openings 12 are closed and sealed by a sealing member 20 . This sealing member 20 is designed to keep the openings 12 sealed even under normal ignition of the inflator 30 . In this way all the generated inflation gases are directed to fill the airbag cushion and virtually none of these gases are lost to atmosphere. This feature enables the inflator 30 to be filled with only the necessary amount of propellant 31 needed to fill the cushion. The sealing member 20 as shown in FIG. 3 is arcuately shaped and closely seals itself along the interior surface 11 of the diffuser 10 . As shown in FIG. 3 , the diffuser 10 has a closed end 17 . Accordingly, this forces the inflation gases to turn in the direction of passage 14 .
As shown in FIG. 4 , the sealing member 20 is molded or otherwise formed with an arcuate shaped base 25 and projecting outward from the base 25 and projecting outward from the base 25 are a plurality of projections 21 , 23 shaped to correspondingly fit into the passageways 14 of the diffuser 10 . In the preferred embodiment two or more of the projections 23 are diagonally opposed and shown extending further than projections 21 . These projections 23 can be used to secure the sealing member 20 tightly to the diffuser 10 as shown in FIG. 1 the projections 23 can be heat staked or ultrasonically welded to the diffuser opening 12 .
As further illustrated in FIG. 4 , the gas inflation pressure is demonstrated by the arrows 100 radially striking the inside surface 27 of the sealing member 20 . When assembled to the diffuser 10 the base 25 is fully supported by the diffuser 10 along the inner surface 11 except at the sealed passages 12 . The sealing member 20 is designed to withstand this pressure and temperature without rupturing or losing seal integrity. Nevertheless, the sealing member 20 is also designed to be easily and rapidly consumed when exposed to fire. The flames generated by fire greatly exceed the temperatures generated by the ignited propellant 31 inside the inflator 30 . This difference in temperature and the fact the flames can rapidly consume the sealing member 20 has enabled the sealing member 20 to rapidly disappear exposing the sealed openings 12 and thus providing a thrust neutral or balanced thrust to be established in the event of exposure to fire. To accomplish this, the total cumulative area of the openings 12 must approximate the open area of the passageway 14 in the discharge channel portion 10 A of the diffuser 10 , preferably the opposing areas are substantially equal. As shown, the diffuser 10 is preferably made of metal of a metal alloy capable of withstanding the heat and pressures exposed during use and in the event of a fire. Metals such as steel or aluminum are generally sufficient.
The sealing member 20 similarly must have a strength exceeding the normal use pressures and temperatures, but must be easily and rapidly consumed when exposed to flames in the event of a fire. Thermoplastic or elastomeric materials can satisfy this condition. The sealing member 20 has a yield strength, an ultimate strength and a percent elongation set to exceed the inflation pressure and temperatures of the ignited inflator 30 in normal use of inflating an airbag. The sealing member 20 when assembled into the diffuser 10 preferably has a yield strength of 33 MPa, ultimate strength of 35 MPa and percent elongation of 50 percent. The sealing member 20 can withstand the maximum inflation pressure and maximum temperature generated by the normally ignited inflator 30 without losing seal integrity in the absence of exposure to external flames or fire related temperatures which are adapted to consume the sealing member 20 exposing the sealed passages 12 . The sealing member 20 when assembled into the diffuser 10 preferably can withstand 2600 psi at 90 degrees C. The sealing member 20 material can be preferably made from DELRIN 100 NC010, an acetal material.
While the preferred invention shows the thrust balancing feature for shipping can be integrally built into the diffuser 10 , it must be appreciated the diffuser 10 can be substituted with a simple endcap if so desired.
In FIG. 5 an alternative embodiment is shown wherein an endcap 50 has a pair of opposing sealing members 20 . The two opposing sealing members 20 when exposed to flame create the described zero thrust or thrust neutral condition. The endcap is a desirable alternative in applications wherein the airbag inflator does not use a diffuser. This and various other modifications employing the flame consumable sealing member 20 are considered within the scope of the appended claims.
With reference to FIGS. 6 and 7 , the present invention inflator 30 with a diffuser 10 having the sealing member 20 is shown. The FIG. 6 depicts the inflator 30 mounted in a bracket assembly 72 with a tube or hose 73 connected to the diffuser 10 and extending to an assembly with a curtain airbag module 74 attached to a bracket 76 with a fill tube 75 connected to hose or tube 73 . This results in an assembly 70 that is pre-manufactured at a facility and shipped for later assembly into a vehicle.
With reference to FIG. 7 , the inflator 30 with a diffuser 10 having a sealing member 20 is shown as an inflation assembly 80 for an inflatable seat belt. That assembly 80 includes the inflator 30 mounted in a bracket 82 with the diffuser 10 connected to a tube or hose 81 that extends to a fill tube 83 and secondary seat bracket 84 . The assembly 80 is adapted to be connected to an inflatable seat belt (not shown). The entire assembly 80 is pre-assembled and shipped to a vehicle manufacturing facility for attachment to seat frame 90 as shown. The inflator 30 when assembled and shipped needs the thrust neutral feature provided by the diffuser 10 with a flame consumable sealing member 20 .
As shown, the present invention provides a thrust neutral feature in a unique way to insure safe transport, but additionally in the event of a car or vehicle fire the sealing member 20 can also safely provide this thrust neutral feature. It being understood that in the event of a crash preceding a fire, the inflator 30 will already be activated and the airbag properly deployed before the sealing member 20 is consumed. This provides a beneficial fail safe feature that insures the airbags always deploy as designed without having the flame consumable sealing member 20 interfering with deployment.
Variations in the present invention are possible in light of the description of it provided herein. While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in this art that various changes and modifications can be made therein without departing from the scope of the subject invention. It is, therefore, to be understood that changes can be made in the particular embodiments described which will be within the full intended scope of the invention as defined by the following appended claims. | An inflator for producing inflation gas from a propellant has a housing for storing the propellant, a diffuser for attachment to the inflator housing and a sealing member. The diffuser has one or more open passages for passing inflation gas upon ignition of the propellant and a plurality of sealed passages oriented opposite to the one or more open passages. The sealing member covers the sealed passages. The sealing member is consumed when exposed to an open flame thereby opening the sealed passages to vent inflation gases opposite the opposed one or more open passages to create a thrust neutral exhaust upon an inadvertent ignition of the propellant due to exposure to fire. | 1 |
SUMMARY OF INVENTION
A tool that is a combination pin straightener and pin spreader to provide a safe, reliable means in a multifaceted easy to handle tool for performing maintenance on stage pin connectors. The tool is comprised of a T-shaped member defining a handle and tube. The handle includes two opposing holes with one end of the handle tapered. The tube which is affixed perpendicularly to the handle includes a blade recessed in the bottom of the tube and affixed parallel to the handle. Both the handle and the tube have finger notches where they intersect.
BACKGROUND OF INVENTION
A. Field of Invention
This invention relates to electrical connector maintenance and repair. In particular to a tool for straightening and spreading electrical contacts, particularly stage pin connectors commonly used in the entertainment industry.
A stage pin connector is typically made of non conductive material fitted with three brass inserts on the receptacle and three matching brass pins on the plug, these brass pins are inserted into the receptacle making electrical contact, the tension in the contact is maintained by a split down the center of each pin on the plug this split makes the pin slightly larger than the inserts causing a solid electrical contact by means of frictional force between the pins and brass inserts. Stage pins come in a variety of sizes ranging from twenty amps to one hundred amps.
B. Description of Prior Art
Previous methods for repairing damaged connectors have been performed by using an exposed blade such a a pocket knife to reestablish the split in the damaged pin. this procedure is both difficult and inaccurate given the large variety of pocket knife blades, it also poses the danger of laceration because of the downward pressure required to split the pin which is the only object between the blade and the hand holding the damaged connector. The most commonly used method of realigning the bent pin is to insert the damaged pin into one of the receptacle inserts and using that receptacle as a leverage arm to bend the damaged pin back to its normal position. Although this is a consistent means of repair it is both inconvenient and dangerous because of potential electrical shock.
It is therefore, a principal object of this invention (do to the high replacement costs of the above mentioned connectors and the dangers imposed trying to maintain said connectors) to provide an apparatus for restoring said connectors to a usable condition which is safe, efficient and economical to the user.
Other objects are to provide a means of increasing the users leverage when splitting pins and eliminating the hazard of lacerations do to an exposed blade.
Another object is to provide a tool with sufficient leverage as means of straightening a variety of the most commonly used pins therefor making a better use of the operators time and eliminating the present dangers.
Still another object is to provide a tool that will straighten a pin that has been bent towards another pin leaving very little clearance between the two said pins.
Another principal object is to provide all the above mentioned objects in one tool which provides the operator with a firm, comfortable and safe grip while performing the needed maintenance.
These and other objects and features of the present invention will become apparent to those skilled in the art from a consideration of the following drawings and claims. The description along with the accompanying drawings provide a selected example of construction of the device to illustrate the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
This invention will now be described with reference to the accompanying drawings in which:
FIG. 1 is a front elevation;
FIG. 2 is a side 1 view;
FIG. 3 is a side 2 view;
FIG. 4 is a bottom view;
FIG. 5 illustrates a connector with correct and incorrect pins;
FIG. 6 illustrates the use of the tool for splitting pins;
FIG. 7 illustrates the use of the tool for straightening bent pins;
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings:
In the illustrated preferred embodiment, the pin straightener and splitting tool, shown generally in FIG. 1 includes a handle (8) and a tube (9) which is preferably formed of a one-piece unitary member that may be about one quarter inch to two inches in thickness. The tool may be made of suitable metal, such as steel, by casting or forging; or it may by machined in two separate pieces (8) and (9) and welded together; or it may be made by molding from a high impact plastic material such as polycarbonate or ABS. The configuration of the tool is such that it lends itself to easy manipulation and highly effective operations throughout its travel. Primarily it consists of a round handle (8) which has two opposing holes at either end (10) and (11) shown in FIG. 2 and FIG. 3, these holes can be of any diameter ranging from one eighth inch to about one inch and can be of any depth ranging from a quarter inch to four inches. These holes are primarily for straightening the bent pins (19) Shown in FIG. 5. One end of the handle (8) is tapered (12), the reduced portion of the handle (12) may be of any dimension of configuration, but is shown in the form of a taper (12), thus permitting it to fit over bent pins (19) as in FIG. 7 that have come to rest at at a narrow distance from another pin (18). Two notches (13) are incorporated on the handle (8) were the tube (9) intersects with the handle, these notches serve as finger grips for increased safety and comfort in handling.
The tube (9) in FIG. 1 and 4 embodies a blade (14) which can be made to any dimension but is shown in the form of a knife blade and is recessed within the tube to prevent lacerations. The blade (14) functions as the splitting device for the damaged stage pins FIG. 5 and 6 (17) . The blade in this illustrated preferred embodiment is affixed parallel to the handle but could function at any position, and can be affixed in many ways such as welding, bolting or set screw. Two notches (15) are also incorporated in the tube were the handle runs across perpendicularly, the indentations are designed for increased comfort and stability for the user.
The pins to be repaired are part of a connector FIG. 5. The assembly (16) usually consists of three pins (17, 18, 19) all of which have a split (20) down the center and are embodied (by a non conductive material (16) along the same face (21). In this illustration a pin (17) is shown with an improper split (22). Another pin (19) is shown bent over, both pins (17, 19) are an illustration of common damage found on stage pin connectors. Both pins need to be corrected to resemble and run parallel to the middle pin (18) shown in FIG. 5, before the connector can be used. It is understood that the omitted members as well as the hidden parts of the assembly are not fully described herein because they form no part of the invention.
When a pin is to be repaired it must first be straightened, this is done by a series of steps preferably shown in FIG. 7. The proper hole (10 or 11) in the handle (8) of the tool is inserted over the damaged pin (19) and by griping the tube (9) in one hand and the connector (16) in to other hand, and applying pressure down on the tube the bent pin can be brought back to an upright position to match the other pins as shown in FIG. 5 as pin (18). The tapered (12) end of the handle (8) has been incorporated in this tool for those pins FIG. 7 that have bent towards another pin (18), these pins are straightened in the same procedure as discussed above.
FIG. 6 illustrates the use of the pin splitting portion of the tool. In this embodiment of the pin splitting process the blade (14) is placed at an angle on top of the closed gap (22) then by applying downward pressure with the tool the split can be reestablished, the blade can then be removed from the pin. It may become necessary to initiate a slight turning action with the handle (8) once the blade has entered the damaged pin to establish the required gap, this will depend on the blade size and the size of pin to be repaired.
It can thus be seen that our novel tool provides a safe, useful and versatile device and method for straightening and splitting damaged stage pin connectors. The invention has been described in the form of a preferred embodiment, but such is not intended to be limiting, and other forms of the invention are considered to be within the scope thereof. | A tool used for straightening and spreading damaged electrical stage pin connectors. The tool consists of a handle and a tube which form a T-shape, there are two opposing holes on the handle for strightening bent pins with one end of the handle being tapered for tight fits. The tube embodies a blade affixed in the bottom of the tube and recessed from the mouth of the tube for prevention of laceration. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention pertains to apparatus and a method for centrifugally casting a babbitting material to a cylindrical bearing shell.
2. Description of the Prior Art
It is known in the commercial prior art to provide a centrifugal casting or babbitting machine in which the cylindrical bearing shell is mounted between opposite end plates on a structure similar to a lathe bed with a fixed headstock having a rotatable plate, and a movable, clamping tailstock plate. The prior art commercial device also includes what may be called a runner trough into which molten babbitt is ladled and from which the molten babbitt passes into the interior of the bearing shell through a conduit extending through the idling end plate. The arrangement known to me as being commercially available also includes a gas heater arrangement for applying heat to the runner trough to prevent the molten babbitt from solidifying in the runner trough. The particular commercial machine of which I am aware also includes an arrangement for spraying cooling water into the space around the bearing shell after the molten babbitt has been applied to the trough and bearing shell.
In another commercially used arrangement of which I am aware a gas-fired heated babbitt tank is located in spaced-apart relation from the idler end plate of the machine and a removable pipe connects the lower end of the tank with the interior of the babbitt shell. A valve on the tank is manually opened for a predetermined time to meter the quantity of babbitt desired for the particular bearing. This arrangement, used for relatively large bearing shells, includes an arrangement for lowering the molten babbitt tank to facilitate loading the tank with the solid babbitt material to be melted, the tank then being elevated to an operating position.
Neither of these arrangements are considered to be wholly satisfactory in my estimation for a number of reasons. First, the manual operations of handling torches for maintaining certain parts at adequate temperatures and the manual ladling of molten metal, introduces problems of safety. The operation of ladling or in any other way of feeding babbitt in other than a continuous pour can frequently result in an inferior bond of the babbitt to the bearing and the presence of porous and laminated layers of babbitting. I attribute such undersirable results as stemming from the intermittent pouring as well as the inexact control of process temperatures, spinning speeds, cooling and pouring times. Another disadvantage of commercially used casting apparatus is that due to the lack of precise pouring controls, excess babbitt is often poured into the casting. As a result of the excess babbitt, increased costs are encountered in the additional machining required as well as the recycling cost for the excess babbitt.
For these and other reasons it is my view that the production level under the prior art arrangements is relatively low compared to what is available from an arrangement in accordance with my invention, and that the rate of rejection with an arrangement according to the invention is substantially reduced.
Accordingly, the aim of my invention is to provide an apparatus and method for centrifugally casting babbitt in which the disadvantages of the prior art commercial arrangements are substantially avoided.
SUMMARY OF THE INVENTION
In accordance with my invention, the apparatus includes spaced apart end-plates between which the cylindrical bearing shell is received, with these end-plates being within an openable housing means which generally encloses the space in which the bearing shell is received. Means are provided for driving the idler end plate between positions in which the bearing shell is clamped and in which it is released. The assembly with which the idler end plate is associated carries an inclined trough and conduit means which connect the lower end of the trough with the interior space of the bearing shell when it is in position for babbitting. A stationary, molten babbitt tank is located adjacent the idler end plate assembly, with a molten babbitt pump being immersed in the tank at an intermediate level. An electric motor is mounted above the tank and connected to drive the pump, and pipe means are connected to the discharge of the pump and extend to a pipe outlet located to overlie the open top side of the trough throughout the range of movement of the trough in its positioning in accordance with the length of a particular bearing shell. The apparatus also includes means for heating the babbitt tank, means for electrically heating and maintaining trough temperature, means for admitting a coolant into the space in the housing about the bearing shell, means for rotating the driven end plate at a predetermined speed in accordance with the size of a particular bearing being babbitted, and means for energizing the electric motor for the pump for a controlled time to feed a specified volume of babbitt into the trough and into the bearing interior in a continuous, uninterrupted flow.
Also in accordance with the arrangement, means are provided for cooling the electric motor for the molten babbitt pump and its bearings, and a control system is provided including switch means and timer means which energize and deenergize the rotating means for the driven end plate, the coolant admission means and the molten babbitt pump in a predetermined sequence of first energizing the rotating means, then the coolant means and then the babbitt pump, and then deenergizing first the babbitt pump, and thereafter the coolant means and the end plate rotating means. The arrangement also includes means responsive to the temperature of the molten babbitt below a predetermined temperature level to prevent the operation of the babbitt pump motor.
Other preferred features will also be described in the description which follows.
DRAWING DESCRIPTION
FIG. 1 is a partly diagrammatic front elevation view of apparatus according to the invention;
FIG. 2 is a top view, again partly diagrammatic, of the apparatus according to the invention; and
FIG. 3 is a partly schematic, partly diagrammatic view of the major parts of the control system for the apparatus.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The apparatus according to the invention as seen in FIGS. 1 and 2 includes a base frame 10 which is similar in form to a lathe bed including a stationary headstock section 12 and a movable, clamping tailstock section 14. The headstock section includes a first rotatable end plate 16 which includes a sealing face 18 thereon against which the outer marginal portion of one open end of a cylindrical bearing shell 20 is received and sealed. The first end plate is driven through a belt drive 22 by a motor 24 which may be a DC motor coupled with an SCR drive to provide an arrangement in which a relatively wide speed range is attainable to permit selecting the proper casting speed for any size bearing which the machine can handle.
An openable, hood-shaped cover 26, shown broken away in FIG. 1 and open in FIG. 2, overlies the space in which the bearing shell 20 is received between the end plates and thus serves along with the underlying structure to generally enclose that space so that a coolant such as water mist may be sprayed or circulated in that space at the appropriate time.
The second or opposite end plate 28 of the tailstock section is an idler end plate which also has a sealing face 30 thereon for receiving the outer marginal portion of the other open end of the bearing shell and sealing it. To drive the second or idler end plate assembly of the tailstock section toward and away from the first end plate, an air-hydraulic cylinder arrangement 32 is provided in the base frame of the unit and is connected to drive the end plate assembly to the left and right to clamp and release, respectively, the bearing shell.
The movable end plate assembly also includes means supporting an upwardly-open, inclined, babbitt receiving trough 34, the lower bottom end of the trough being connected by a conduit 36 to pass to the interior space of the bearing shell the molten babbitt received by the trough. Several electric mica heater elements are applied to the outside wall of the trough 34 and then are covered with thermal insulation 38, the top of the trough being open as seen in FIG. 2.
A molten babbitt tank 40 is stationarily mounted upon the frame 10 at the end of the apparatus adjacent the movable end plate assembly and molten babbitt trough. The tank is electrically heated and is provided with thermal insulation so that the babbitt therein can be maintained at least at a given temperature for the particular babbitt material in the tank. A centrifugal pump 42 is immersed at an intermediate level in the tank and is adapted to be driven by an electric motor 44 mounted above the tank. An angle-shaped pipe 46 has one portion of its length immersed in the tank with its end connected to the discharge of the pump, and extends with its other portion to its outlet at a location overlying the open top side of the trough 34. At least that portion of its length extending from the angle to its open end over the trough is wrapped with thermal insulation. The length of the open slot of the trough 34 is dimensioned such, relative to the location of the outlet of the pipe 46, that within the range of movement of the movable end plate in accordance with the length of the particular bearing which is to be babbitted, the open end of the pipe 46 will always overlie the slot.
A water jacket 48 is provided adjacent the lower end of the motor 44 and in the vicinity of the motor bearings to prevent overheating of the motor and bearings from the molten babbitt in the tank. The water jacket is fed by piping 50.
A second stationary tank 52 for molten babbitt is stationarily mounted on a platform 54 adjacent the first tank. This second tank is identical in its general character to the first tank and accordingly includes an immersed pump (not shown) and a motor 56 and water jacket, etc.
In the particular embodiment forming the basis for the description herein, the one tank is provided with babbitt having a lead base and the other tank is provided with babbitt having a tin base. Because of the difference in the base of the babbitt in the two different tanks, the two different tanks are maintained at different temperatures. For all sizes of bearings, the tin base babbitt is maintained at a temperature of about 850° F. (454° C.), while the temperature of the lead base babbitt is maintained in range of about 725° F. to 775° F. (385° to 413° C.) for the different sizes and different types of bearing shells which are to be babbitted.
It is considered important that the pump in each tank be located at an intermediate level in which contamination from both surface dross and "bottom of the pot" impurities is minimized.
The piping 46 and 58 which leads from the pumps in the two tanks is preferably provided with a thermal insulation blanket around the pipes to aid in maintaining the heat content of the babbitt as it flows to the heated trough 34. It has been found convenient in the embodiment illustrated to join the pipes at a location immediately above the top open slot of the trough so that a single outlet is provided regardless of the type of babbitt used. A siphon break (not illustrated) is included in the piping 46 and 58 to insure a positive cutoff of babbitt flow when the pump 42 is shut off.
The apparatus also includes means for circulating a coolant about the bearing shell 20 in the housing at the appropriate time. In the illustrated embodiment this arrangement includes a water spray pipe 60 in the lower part of the space in which the bearing shell 20 is mounted for rotation, and a water supply pipe 62 having a solenoid operated valve 64 therein is provided to control the flow.
The main parts of the control system are illustrated in the diagrammatic layout of FIG. 3. The system includes three programmable timers 66, 68 and 70 containing switch means and controlling the "On-Off" cycle times of the main drive motor 24, the molten babbitt pump 44, and the cooling spray solenoid valve 64, respectively. For automatic operation, these timers are set for specific time periods in accordance with a schedule developed in accordance with bearing size and types. The timer 66 is connected by the line 72 to an AC-DC adjustable speed drive which controls the application of power to the motor 24. Also associated with the drive motor and its circuitry is a speed control rheostat and indicator, which are not shown. Other safety and convenience elements not shown include an air switch and a housing covered limit switch in the circuitry to the timer means which prevent certain operations if the cover is not closed at the proper time and if the air pressure for the air-oil clamping cylinder 32 (FIG. 1) is below a safe clamping pressure.
The control lines 74 from the pump timer 68 to the magnetic starter 76 for the pump also include a thermostatic switch 78 in one of the lines, this switch reflecting the molten babbitt temperature and being in an open position if the temperature of the babbitt is below a predetermined level, so that operation of the babbitt pump is then precluded.
The control lines 80 connect the third timer 70 to the solenoid valve 64 which controls the admission of spray cooling water into the sprayer 60.
The controls for the heater for the trough 34, and for the babbitt melting tanks are straightforward and accordingly are not shown in FIG. 3. For the convenience of the operator of the machine, the temperatures of the trough and of the melting pots are indicated by visual means (not shown) to prevent an operation which would be aborted by the thermal switch 78 being open due to insufficient temperature. Further, the operator is given instructions about energizing the melting pot heaters and the trough heaters at predetermined times prior to operating the apparatus. Also, whenever the melting pots are on or cooling down the water lines to the pump motors 44 and 56 are open to allow water to flow through the water jacket.
For operating the apparatus, the operator goes through a start-up and operation sequence which basically proceeds as follows. The melting pot and trough heater temperatures are checked in accordance with the charts provided to the operator. The water flow through the water jackets for the pump motors is checked. The air pressure for the air cylinder 32 is checked to see whether it is adequate. Each of the timers 66-70 is set to the proper "On-Off" times as indicated on the operator's chart. The switches which control whether the apparatus is to operate in an automatic fashion or whether individual elements are to be run manually for checking are placed in the automatic position. The housing cover 26 is closed so that the main drive motor can be tested in a manual position and the proper speed set up. Then the switch for the main drive motor is switched back to the automatic position. Then the cover is again opened and the opening between the end plates 16 and 28 is adjusted so that the particular length of bearing to be babbitted will set between them.
The basic steps in preparing a bearing shell for the actual babbitting operation will be briefly outlined. The bearing shells 20, which comprise two longitudinally split parts, are assembled and fluxed and then tinned in flux and tin tanks. The tin tank is maintained at temperatures well above the proper temperature for the casting to have when it is going to be babbitted, and the bearing shell is allowed to remain in the tin tanks for a period which permits it to reach a temperature sufficiently above its proper temperature for babbitting that the additional operations can be carried out on the shell without it cooling below the specified temperature before the babbitting.
Once the bearing has been properly tinned, aluminum shims are inserted between the mating halves of the shell and the bolts holding the two parts together snugged up. The bearing shell is then moved to the apparatus and is lowered into place to line up with the sealing face 18 on the first end plate 16. The clamping cylinder 32 is then actuated to move the opposite end plate 28 to the left into a position in which it clamps the bearing shell, in properly aligned and seated relation, between the two end plates. The clamp control is then switched to a stop position, the bolts of the bearing shell are tightened, and the chain and eye hook which has been used for manipulating the heavy bearing shell is then removed. The clamp switch is then placed back in the clamped position.
The temperature of the bearing shell 20 is then checked to see whether it is at the specified temperature. If it is too hot, it is permitted to cool until it reaches the proper temperature range. If it should occur that the temperature of the bearing is too cold at this time, the shims must be removed and the bearing shell reheated. If the bearing shell is within the proper temperature range, the cover 26 is closed and locked and a starting switch is pushed for the automatic operation.
The sequence which occurs with the automatic operation of the control system results in energizing in a predetermined sequence and for preselected times, first the motor 24 driving the first end plate, then the coolant circulating means accomplished through opening the solenoid valve 64, and then the molten babbitt pump motor 44 or 56, depending upon which tank is being used. After energizing in that sequence, the sequence of deenergizing these elements include first deenergizing the babbitt pump, after a relatively short run, and after a considerably longer period thereafter the coolant circulating means, and finally the main drive motor for the driven end plate.
I find it desirable to begin the spray cooling before the molten babbitt pump is energized, and generally start the cooling about 6 seconds before the babbitt pump is energized. The molten babbitt pump is energized for only a short time (the exact time of cource being dependent upon the size and capacity of the pump) but I maintain the coolant flow until very shortly before the main drive motor 24 is deenergized. It is considered desirable that the coolant start prior to the flow of the molten babbitt so that there is a tendency for the bearing shell to cool in a direction of from outside inwardly. This is believed to be useful to maintain a good bond between the babbitt and the shell, and this also minimizes leakage of the babbitt in an outward direction as the shell is being spun. The main drive motor speeds are determined in accordance with the diameter size of the bearing, and as example, will vary with the inverse square root of the radius, thereby maintaining a constant centrifugal force for casting of the babbitt metal. It is also generally preferred that for larger bearings the temperature of the casting or shell be higher than for the smaller bearings before the operation takes place, due to the larger mass of the bearing, although in the case of bearings of certain character and of a limited size range it may be permissible to have the casting temperature at the same level regardless of the size.
It is believed deserving of emphasis that the benefits noted hereinbefore derive from the automatic cycle carried out in which close control of critical variables is maintained. One of the more important elements of the apparatus yielding control of a critical variable is the use of the immersed molten babbitt pump which is energized for a specific time and produces a continuous uninterrupted flow of the babbitt to yield a relatively precise quantity of babbitt at the proper temperature. With the pump immersed to an intermediate location, both floating dross and bottom of the pot impurities are excluded from the pumped flow. By providing a fixed length of pipe with a siphon break leading from the pump to the trough, the resistance to babbitt flow remains fixed. This fixed parameter, coupled with the uniform head on the pump permits the use of a relatively inexpensive centrifugal pump of a type lending itself to the motor and bearing cooling arrangement, instead of being required to use a very expensive positive displacement pump. The automatic cycle also derives the benefit of maintaining all temperature variables involved in the centrifugal casting of babbitt, and once set, achieve a repetitiveness not before possible. | The apparatus and method provide an arrangement in which molten babbitt is fed into a spinning cylindrical bearing shell from a stationary molten babbitt tank having a babbitt pump immersed in the tank at an intermediate level, with the pump discharge being connected to piping to discharge molten babbitt into a babbitt trough from which the babbitt feeds to the interior of the spinning shell. The babbitt pump is driven for a controlled time period to feed a specified volume of babbitt into the trough and bearing in a continuous uninterrupted flow so that a carefully metered amount of molten babbitt is fed to the bearing. The apparatus also includes a control system operable to energize and deenergize various operating elements in a sequence including the drive motors, means for admitting a coolant about the hot spinning bearing shell, and the molten babbitt pump. | 1 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method and equipment for semiconductor processing, and to a semiconductor processing equipment module, especially, for cleaning semiconductor wafers to achieve a total system which provides high efficiency FA (factory automation).
2. Description of the Related Art
FIG. 25 is a schematic diagram showing the structure of conventional semiconductor processing equipment such as (semiconductor) wafer cleaning equipment. In this figure, one or more wafer cassettes (not shown) are carried from the outside into wafer cleaning equipment 1 via a loader 2. A wafer taking-out unit 3 takes out only wafers (not shown) from the carried-in wafer cassettes. These wafers are wet-cleaned in a wafer cleaning bath 4. After the cleaning, a wafer inserting unit 5 inserts the wafers into a cassette containing no wafer in it (not shown, described as vacant cassette hereafter). In the processing, a wafer carrying robot 7 holds wafers taken out by the above wafer taking-out unit 3, and carries them into the wafer cleaning bath 4. Furthermore, after the wafers are cleaned, the wafer carrying robot 7 carries the wafers to the wafer inserting unit 5. Cassettes containing cleaned wafers (not shown) are carried out of the wafer cleaning equipment 1 via an unloader 6.
The operation of a conventional wafer cleaning equipment having the structure shown above is described next. As shown in FIG. 13, when one through four product cassettes containing wafers to be cleaned are placed in the loader 2, the wafer taking-out unit 3 separates the wafers from the cassettes. Then, the wafers are carried to the cleaning bath 4 by the wafer carrying robot 7. The cassettes which became vacant are carried out of the wafer cleaning equipment 1 via the loader 2.
After the wafers are cleaned in the cleaning bath 4, the wafers are carried to the wafer inserting unit 5 by the wafer carrying robot 7. Then, the wafer inserting unit 5 inserts the wafers into vacant cassettes which are placed in an unloader 6 in advance. After that, the product cassettes containing the cleaned wafers are carried out of the wafer cleaning equipment 1 via the unloader 6.
The wafer cleaning equipment described above has a very limited function that it takes wafers out of product cassettes, performs wet cleaning for wafers, and inserts wafers back into product cassettes. As a result, further operations have to be performed at a certain place outside of the wafer cleaning equipment to remove and keep ID cards attached to product cassettes before wafers are carried into the wafer cleaning equipment. Moreover, it is also necessary, at a place outside the wafer cleaning equipment, to attach corresponding ID cards to product cassettes carried out of the wafer cleaning equipment after the wafers are cleaned. This prevents achievement of full factory automation (described by FFA hereafter) by robots.
Furthermore, in conventional wafer cleaning equipment, carrying products into the equipment and placing them into a cleaning bath are carried out on one same side of the equipment, but carrying products out of the cleaning bath is done on the other side of the equipment. Therefore, to carry products in/out a cleaning bath, there must be plural carrying robots such as robots for carrying products into equipment before cleaning, robots for carrying products out of the equipment after cleaning, and robots for carrying vacant product cases from a location via which products to be cleaned are put into equipment to a location via which cleaned products are carried out. This gives rise to problems such as high costs for FA or large areas occupied by robots in clean rooms.
SUMMARY OF THE INVENTION
It is an object of the present invention to solve the problems described above. More specifically, it is an object of the present invention to provide a semiconductor processing method and equipment and a semiconductor processing equipment module to achieve high efficiency FA (factory automation) with small size equipment whereby perfect management of product cases and ID cards are performed.
In order to achieve the objects described above, the present invention provides semiconductor processing equipment which comprises: ID card removing means for removing an ID card from a case which contains semiconductor wafers and to which the ID card is attached; ID-card keeping means for keeping the removed ID card; processing means for processing semiconductor wafers; a loader which takes semiconductor wafers to be processed out of the cases and puts the semiconductor wafers in the processing means; ID-card attaching means which takes an ID card corresponding to semiconductor wafers processed already out of the ID-card keeping means and attaches the ID card to the case; and an unloader which takes processed semiconductor wafers from the processing means and puts the semiconductor wafers into the case.
The present invention also provides a semiconductor processing method which comprises the steps of: carrying a case, which contains semiconductor wafers and to which an ID card is attached, into semiconductor processing equipment from a first side of the semiconductor processing equipment; removing the ID card from the case; taking semiconductor wafers to be processed out of the cases; carrying the semiconductor wafers taken out of the cases into a processing means via a second side opposite to the first side of the semiconductor processing equipment; processing semiconductor wafers with the processing means; attaching the ID card corresponding to semiconductor wafers taken out of the case to the case; taking semiconductor wafers, which are processed already, out of the processing means via the first side of the semiconductor processing equipment; putting the semiconductor wafers, which are taken out of the processing means, into the case to which the ID card is attached; and carrying the case outside of the semiconductor equipment via the first side of the semiconductor equipment.
Furthermore, the present invention provides a semiconductor processing module which comprises:
plural pieces of semiconductor processing equipment comprising: ID card removing means for removing an ID card from a case which contains semiconductor wafers and to which the ID card is attached; ID-card keeping means for keeping the removed ID card; a processing means for processing semiconductor wafers; a loader which takes semiconductor wafers to be processed out of the cases and puts the semiconductor wafers in the processing means; ID-card attaching means which takes an ID card corresponding to semiconductor wafers processed already out of the ID-card keeping means and attaches the ID card to the case; and an unloader which takes processed semiconductor wafers from the processing means and puts the semiconductor wafers into the case;
case stocking means for stocking cases; and
case carrying means for carrying cases between the plural pieces of semiconductor processing equipments and the case stocking means.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a cassette containing plural wafers;
FIG. 2 is a schematic diagram showing an embodiment of semiconductor processing equipment of the present invention;
FIG. 3 is a schematic perspective view of wafer cleaning equipment of a first embodiment of the present invention;
FIG. 4 is a schematic diagram for explanation of an ID-card handling robot;
FIG. 5 is a schematic diagram for explanation of the loading sequence of wafers to be cleaned in the equipment shown in FIG. 3;
FIG. 6 is a schematic diagram for explanation of the unloading sequence of cleaned wafers from the equipment shown in FIG. 3;
FIG. 7 is a side view showing an ID-card handling robot and the vicinity of it;
FIG. 8 is an elevational view showing an ID-card handling robot and the vicinity of it;
FIG. 9 is an elevational view showing an ID-card handling robot and the vicinity of it for explanation of the operation of removing and keeping an ID card;
FIG. 10 is a side view showing an ID-card handling robot and the vicinity of it for explanation of the operation of removing and keeping an ID card;
FIG. 11 is a side view showing an ID-card handling robot and the vicinity of it for explanation of the operation of removing and keeping an ID card;
FIG. 12 is a schematic diagram showing an embodiment of wafer cleaning equipment for explanation of the loading sequence of wafers to be cleaned;
FIG. 13 is a flowchart showing the loading sequence of wafers to be cleaned;
FIG. 14 is a schematic diagram showing an embodiment of wafer cleaning equipment for explanation of the unloading sequence of cleaned wafers;
FIG. 15 is a flowchart showing the unloading sequence of cleaned wafers;
FIG. 16 is a schematic diagram showing an embodiment of wafer cleaning equipment of a second embodiment of the present invention;
FIG. 17 is a schematic diagram for explanation of the loading sequence of wafers to be cleaned in the equipment shown in FIG. 16;
FIG. 18 is a schematic diagram for explanation of the unloading sequence of cleaned wafers from the equipment shown in FIG. 16;
FIG. 19 is a schematic diagram for explanation of the loading sequence of wafers to be cleaned;
FIG. 20 is a schematic diagram for explanation of the unloading sequence of cleaned wafers;
FIG. 21 is a schematic diagram showing an embodiment of a wafer cleaning module of a third embodiment of the present invention;
FIG. 22 is a schematic diagram for explanation of the flow of cassettes in the wafer cleaning module shown in FIG. 21;
FIG. 23 is a schematic diagram showing an embodiment of a wafer cleaning module of a fourth embodiment of the present invention;
FIG. 24 is a schematic diagram for explanation of the flow of cassettes in the wafer cleaning module shown in FIG. 23; and
FIG. 25 is a schematic diagram showing a conventional wafer cleaning equipment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to the figures, semiconductor processing equipment of the present invention is described below.
FIG. 1 is a perspective view of a (product) case (product cassette, cassette) 37 for use in semiconductor processing equipment of the present invention. This cassette 37 is capable of containing plural wafers 50 and has a pocket 51 in which an ID card (product card) 38 is attached.
FIG. 2 is a schematic diagram showing an embodiment of semiconductor processing equipment of the present invention. The semiconductor processing equipment, such as wafer cleaning equipment 39 with capability of keeping ID cards, has an ID-card handling means 61 which comprises an ID-card removing means for removing an ID card 38 from a cassette (case) 37 shown in FIG. 1, an ID-card keeping means for keeping an removed ID card 38, an ID-card attaching means which takes an ID card 38 corresponding to processed wafers 50 from the ID-card keeping means and attaches it to the cassette 37. The wafer cleaning equipment 39 also has a processing means 64 for processing wafers 50, a loader 2 which takes wafers 50 to be processed from the cassette 37 and puts the wafers 50 into the processing means 64, and an unloader 6 which takes the processed wafers 50 from the processing means 64 and puts them into the cassette 37.
FIRST EMBODIMENT
In the following, referring to the figures, a first embodiment is described. FIG. 3 is a schematic perspective view of wafer cleaning equipment with a capability of holding ID cards. This wafer cleaning equipment 39 with the capability of holding ID cards has a carrying-in/carrying-out lane 20 for carrying in up to four cassettes 37 from outside or carrying them outside. It also has an ID-card handling robot 30 which takes an ID card 38 attached to a cassette 37 and inserts it into an ID-card stocker 31, an ID-card keeping means, and which takes an ID card 38 from the ID-card stocker 31 and inserts it into a cassette 37. Using an ID-card removing lane 21, this ID-card handling robot 30 functions as an ID-card removing means for taking an ID card 38 from a cassette 37. Furthermore, using an ID-card inserting lane 22, the ID-card handling robot 30 also functions as an ID-card attaching means for inserting an ID card 38 into a cassette 37.
For the sake of putting vacant cassettes on an unloader 6, there is an unloader waiting lane 23 where vacant cassettes wait for a while until the unloader 6 becomes capable of accepting vacant cassettes. Furthermore, there is a robot (d) 32 which is capable of carrying up to four cassettes between the carrying-in/carrying-out lane 20, the ID-card removing lane 21, the ID-card inserting lane 22, the unloader waiting lane 23, and the unloader 6. On the other hand, slider (a) 29 can carry up to four cassettes by sliding them between the ID-card removing lane 21, the card handling position just under the ID-card stocker 31, and the ID-card inserting lane 22. A slider 33 carries "cassettes containing wafers to be cleaned with no ID card"--it carries two cassettes at a time--from the ID-card removing lane 21 to a transfer lane 24. The transfer lane 24 has a capacity of up to four of such cassettes. A robot 34a carries up to two cassettes from the transfer lane 24 onto a conveyer 35, and also carries up to two vacant cassettes from the conveyer 35 either to a vacant-cassette buffer 26 or to a vacant-cassette carrying-out lane 25.
The conveyer 35 comprises a table and a driving unit. This table has a capacity of up to two cassettes. The driving unit drives this table such that the table slides back and forth between each end of the conveyer 35. A slider 40 carries up to two cassettes by sliding them on the vacant-cassette carrying-out lane 25. A robot 34b carries up to two cassettes between the conveyer 35 and a transfer lane 27. A robot 36 carries up to two cassettes between the transfer lane 27, a loader 2, and a loader waiting lane 28. Here, those robots which carry cassettes 37 on the equipment are part of a first ease carrying means.
FIG. 4 is a schematic diagram for explanation of the robot 32, the robot 34, and the ID-card handling robot 30.
The robot 32 comprises a X-shaft (a robot travelling shaft), a Y-shaft (a back-and-forth moving hand for holding two cassettes), a Z-shaft (up-and-down movement), and an opening/closing mechanism for the hand for holding cassettes. This robot (d) 32 can carry up to four cassettes at the same time, and can put one or two cassettes on any place (within the restriction of the range of the Y-shaft movement) according to instruction data. The robot 34 comprises a X-shaft (moving cassette holding hand back and forth), a Z-shaft (up-and-down movement), a θ-shaft (a rotation shaft), and an opening/closing mechanism of a hand. This robot 34 carries cassettes 37 from the transfer lane 24 onto the conveyer 35 by 180° rotation.
The ID-card handling robot 30 takes out up to four ID cards 38, at the same time, from the pocket 51 on a side of a cassette placed under the ID-card handling robot 30, and inserts those ID-cards into the ID-card stocker 31 above the cassettes 37. Conversely, it also takes ID cards 38 from the ID-card stocker 31 and inserts them into the pocket 51 on a side of a cassette.
FIG. 5 is a schematic diagram for explanation of the loading sequence of wafers to be cleaned. FIG. 6 is a schematic diagram for explanation of the unloading sequence of cleaned wafers. Incidentally, the wafer cleaning is carried out for up to two cassettes at a time.
First, referring to FIG. 5, the wafer loading sequence is described below. In the following description, step numbers correspond to the numbers in the figure with a surrounding circle.
Step 51: At the beginning of all the steps, four cassettes are put on the carrying-in/carrying-out lane 20. One through four cassettes can be put on it.
Step 52: The robot 32 carries all of these four cassettes at the same time to the ID-card removing lane 21.
Step 53: The slider 29, further, carries all four cassettes at the same time to a place under the ID-card stocker 31.
Step 54: The ID-card handling robot 30 carries four cards (wafers) at the same time to the card stocker 31.
Step 55: The slider 29 carries all four cassettes at the same time to the ID-card removing lane 21.
Step 56: The slider 33 carries two cassettes at a time to the transfer lane 24. Here, the fist two cassettes are called cassette group A, and the latter two cassettes are called cassette group B.
Step 56': The slider 33 carries cassettes of the cassette group B to the proper position so that the robot 34a can take the cassettes. Here, the prime denotes a step concerning the cassette group B.
Step 57: The robot 34a puts cassettes of the cassette group A on the conveyor 35.
Step 58: The conveyor 35 carries cassettes of the cassette group A to the end of the conveyor on the side where the loader 2 is located.
Step 59: The robot 34b carries cassettes of the cassette group A to the transfer lane 27.
Step 60: The robot 36 carries cassettes of the cassette group A to the loader waiting lane 28.
Step 61: The robot 36 places cassettes of the cassette group A on the loader 2. The wafer taking unit 3 takes out the wafers from cassettes of the cassette group A, thus the cassette group A becomes vacant cassette group A remaining on the loader 2.
Step 57': On condition that the loader waiting lane 28 and the transfer lane 27 are vacant, the robot 34a puts cassettes of the cassette group B on the conveyor 35.
Step 58': The conveyor 35 carries cassettes of the cassette group B to the end of the conveyor on the side where the loader 2 is located.
Step 59': The robot 34b carries cassettes of the cassette group B to the transfer lane 27.
Step 60': The robot 36 carries cassettes of the cassette group B to the loader waiting lane 28.
Step 61': The robot 36 places cassettes of the cassette group B on the loader 2. The wafer taking-out unit 3 takes the wafers from cassettes of the cassette group B, thus the cassette group B becomes vacant cassette group B remaining on the loader 2
Step 62: On condition that the transfer lane 27 is vacant, the robot 36 carries cassettes of the vacant cassette group A to the transfer lane 27.
Step 63: The robot 34b puts cassettes of the vacant cassette group A on the conveyor 35.
Step 64: The conveyor 35 carries cassettes of the vacant cassette group A to the end of the conveyor on the side where the unloader 6 is located.
Step 65: The robot 34a carries cassettes of the vacant cassette group A to the vacant-cassette carrying-out lane 25.
Step 66: The slider 40 puts cassettes of the vacant cassette group A on the vacant-cassette carrying-out lane 25 as far as possible.
Step 62': The robot 36 carries cassettes of the vacant cassette group B to the transfer lane 27.
Step 63': The robot 34b puts cassettes of the vacant cassette group B on the conveyor 35.
Step 64': The conveyor 35 carries cassettes of the vacant cassette group B to the end of the conveyor on the side where the unloader 6 is located.
Step 65': The robot 34a carries cassettes of the vacant cassette group B to the vacant-cassette carrying-out lane 25.
Thus, all four cassettes of the vacant cassette groups A and B are now ready and the cassettes are carried out of the wafer cleaning equipment 39.
Incidentally, the vacant-cassette buffer lane 26 is used in the following cases:
(1) In case there already exist cassettes on the vacant-cassette carrying-out lane 25 when the cassettes of the vacant cassette group A are carried to the end of the conveyor 35 on the side where the unloader 6 is located, the cassettes of the vacant cassette group A wait for a while on the vacant-cassette buffer lane 26 until the vacant-cassette carrying-out lane 25 becomes available.
(2) When it is required to change the order of positions of the vacant-cassette groups A and B on the vacant-cassette carrying-out lane 25, cassettes of the vacant-cassette group A coming earlier are put on the vacant-cassette buffer lane 28 to wait so that cassettes of the vacant-cassette group B coming later can be put on the vacant-cassette carrying-out lane 25 before the vacant-cassette group A.
Referring to FIG. 6, the unloading sequence of cleaned wafers is described next.
Step 101: On condition that the wafer cleaning equipment 39 with the capability of holding ID cards requires vacant cassettes to be supplied in it, and that the carrying-in/carrying-out lane 20 and the ID-card inserting lane 22 are vacant, four vacant cassettes are put on the carrying-in/carrying-out lane 20.
Step 102: The robot 32 carries these four vacant cassettes at the same time to the ID-card inserting lane 22.
Step 103: The slider 29 carries the four vacant cassettes to the position under the ID-card stocker 31.
Step 104: The ID-card handling robot 30 removes four corresponding ID cards at the same time from the ID-card stocker 31 and inserts them into the vacant cassettes.
Step 105: The slider 29 carries the vacant cassettes with an inserted ID-card to the ID-card inserting lane 22.
Step 106: The robot 32 carries these four cassettes to the unloader waiting lane 23.
Step 107: The robot 32 puts the first group of two cassettes (called cassette group A hereafter), on the unloader 6. The wafer inserting unit 5 inserts cleaned wafers into the cassettes of the cassette group A on the unloader 6.
Step 108: The robot 32 carries the cassettes of the cassette group A back to the unloader waiting lane 23.
Step 107': On the hand, the robot 32 puts the remaining two cassettes (called cassette group B hereafter) on the unloader 6. The wafer inserting unit 5 inserts cleaned wafers into the cassettes of the cassette group B on the unloader 6.
Step 108': The robot 32 carries the cassettes of the cassette group B back to the unloader waiting lane 23.
Step 109: The robot 32 carries all of four cassettes (of both cassette groups A and B) at the same time to the carrying-in/carrying-out lane 20.
Step 110: These four cassettes are carried out of the wafer cleaning equipment 39.
The details of the ID-card handling robot 30 are described in the following.
FIGS. 7 and 8 are respectively a side view and an elevational view showing the ID-card handling robot (main body) 30 and the vicinity of if. In these figures, the ID-card removing lane 21 and the ID-card inserting lane 22 are located on opposite sides of the ID-card handling robot 30. The slider 29 carries cassettes 37 between the ID-card removing lane 21, the ID-card inserting lane 22 and the position just under the ID-card handling robot 30. Furthermore, there is a card guide 43 which functions as a guide when an ID-card 38 is pushed up by a card pusher 42.
The ID-card handling robot 30 comprises a back-and-forth shaft 45 and an up-and-down shaft 46. Here, the back-and-forth shaft moves a gripper 44 back and forth for holding four ID cards 38 at the same time. The up-and-down shaft 46 moves the gripper 44 up and down. Moreover, there is a controller 47 comprising a control unit and a memory unit, wherein the control unit controls the operations of the ID-card handling robot 30, the card pusher 42, and the card guide 43, and wherein the memory unit contains card position data for each ID card 38 held in the card stocker 31.
The ID-card handling robot 30 operates as follows:
FIGS. 9-11 are schematic diagrams for explanation of how ID cards are removed and held. FIG. 9 is an elevational view showing the ID-card handling robot 30 and the vicinity of it, and FIGS. 10 and 11 are a side view of it. Referring to these figures, ID cards are removed and held according to the following steps (1)-(3).
(1) The slider 29 carries a cassette on the ID-card removing lane 21 to the position under the ID-card handling robot 30.
(2) After the card guide 43 moves to the vicinity of ID cards, the card pusher 42 pushes up the ID cards 38. Furthermore, the gripper 44 of the ID-card handling robot 30 holds these ID cards 38.
(3) The back-and-forth shaft 45 and the up-and-down shaft 46 of the ID-card handling robot 30 are moved to put the ID cards 38 in the card stocker 31.
Furthermore, ID cards 38 are inserted into cassettes according the steps opposite to the above steps (1)-(3), with a slight difference, that is, cassettes are carried by the slider 29 from the ID-card inserting lane 22 to the position just under the ID-card handling robot 30.
In addition to the above descriptions which show the loading sequence for wafers to be cleaned and the unloading sequence for cleaned wafers according to the first embodiment of the present invention, further descriptions are given in FIGS. 12-15 to show major points of these sequences. FIGS. 12 and 13 are a schematic diagram and a flowchart respectively for explanation of the loading sequence of wafers to be cleaned. FIGS. 13 and 14 are a flowchart and a schematic diagram respectively for explaining of the unloading sequence of cleaned wafers.
SECOND EMBODIMENT
Referring to the figures, a second embodiment of the present invention is described below.
FIG. 16 is a schematic diagram of wafer cleaning equipment with capability of holding ID cards in accordance with the second embodiment of the present invention. FIG. 17 is a schematic diagram for explanation of the loading sequence of wafers to be cleaned which is performed using the equipment shown in FIG. 16. FIG. 18 is a schematic diagram for explanation of the unloading sequence of cleaned wafers which is performed using the equipment shown in FIG. 16. In these figures, members of the equipment of the second embodiment are the same as those of the equipment of the first embodiment, except for the vacant-cassette stocker 41 of the second embodiment which is provided instead of the vacant-cassette carrying-out lane 25 of the first embodiment. Accordingly, the basic description of the second embodiment is made with the help of the reference numerals used in the first embodiment, and different matters are mainly explained.
First, the loading sequence of wafers to be cleaned is described below, referring to FIG. 17.
Steps 51-64: The same as those in the first embodiment.
Step 65: The robot 34 carries the cassettes of vacant-cassette group A to the vacant-cassette stocker 41.
Step 66 of the first embodiment--putting cassettes on the lane as far as possible--is not carried out in the second embodiment.
Step 65': The robot 34 carries the cassettes of vacant-cassette group B to the vacant-cassette stocker 41.
Step 67: Four cassettes (cassettes of the vacant-cassette groups A and B) are stocked in the vacant-cassette stocker 41. Incidentally, there is no operation related to a vacant-cassette carrying-out lane 25, because no vacant-cassette carrying-out lane 25 is provided.
Referring to FIG. 18, the unloading sequence of cleaned wafers is described next.
Step 101: The robot 34a carries two vacant cassettes (cassettes of the vacant-cassette group A) from the vacant cassette stocker 41 to the transfer lane 24.
Step 102: The slider 33 carries these vacant cassettes to the ID-card removing lane 21.
Step 101': The robot 34a carries two remaining vacant cassettes (cassettes of the vacant-cassette group B) from the vacant-cassette stocker 41 to the transfer lane 24.
Step 102': The slider 33 carries these vacant cassettes to the ID-card removing lane 21.
Steps 103-110: The same as those in the first embodiment.
In addition to the above descriptions which show the loading sequence for wafers to be cleaned and the unloading sequence for cleaned wafers according to the second embodiment of the present invention, further descriptions are given in FIGS. 19 and 20 to show major points of these sequences. FIGS. 19 is a schematic diagram for explanation of the loading sequence of wafers to be cleaned. FIGS. 20 is a schematic diagram for explanation of the unloading sequence of cleaned wafers. In the second embodiment, the vacant-cassette stocker 41 provided inside the equipment eliminates the necessity to carry vacant cassettes out of the equipment, thus it results in the reduction in the number of robots for carrying vacant cassettes.
THIRD EMBODIMENT
In the following, a semiconductor processing equipment module of the present invention is described. FIG. 21 is a schematic diagram showing a semiconductor processing equipment module, such as a wafer cleaning module, using wafer cleaning equipment with capability of holding ID cards as shown in the first embodiment. In this figure, a robot 8, a case (cassette) carrying means, carries up to four cassettes between cassette cleaning equipment 9 as a case (cassette) cleaning means, a module carrying-in lane 11, a module carrying-out lane 13, a case (cassette) stocker 16 as a case stocking means, carrying-in/carrying-out lanes 20a and 20b and vacant-cassette carrying-out lanes 25a and 25b of each of two pieces of wafer cleaning equipment 39a and 39b.
Referring to FIG. 22, the flow of cassettes in the wafer cleaning module is described below.
Step 201: Four wafer cassettes are put on the module carrying-in lane 11. (One through four cassettes can be put on it.)
Steps 202 and 203: The robot 8 carries these cassettes either to the cassette stocker 16 or directly to the carrying-in/carrying-out lane 20b of the wafer cleaning equipment 39b. Four vacant cassettes from which wafers have been removed in the wafer cleaning equipment 39b are carried to the vacant-cassette carrying-out lane 25b.
Step 204: The robot 8 carries these four vacant cassettes to the cassette cleaning equipment 9. The cassettes are stocked after they are cleaned in the cassette cleaning equipment 9.
Step 205: The robot 8 carries some number of vacant cassettes which the wafer cleaning equipment 39b requires from the cassette cleaning equipment 9 to the carrying-in/carrying-out lane 20b. Then, at the wafer cleaning equipment 39b, cleaned wafers are inserted into the vacant cassettes and the cassettes are carried to the carrying-in/carrying-out lane 20b.
Step 206: The robot 8 carries these cassettes containing cleaned wafers either to the cassette stocker 16 or directly to the module carrying-out lane 13. Cassettes which are carried into the cassette stocker 18 are carried to the module carrying-out lane 13 at an appropriate time by the robot 8.
Step 207: The cassettes containing cleaned wafers are carried out from the module carrying-out lane 13.
Operations similar to the above are also performed for the wafer cleaning equipment 39a.
FOURTH EMBODIMENT
FIG. 23 is a schematic diagram showing a wafer cleaning module using wafer cleaning equipment with capability of holding ID cards shown in the second embodiment. In this figure, a robot 8 carries up to four cassettes between a module carrying-in lane 11, a module carrying-out lane 13, a case (cassette) stocker 16, and carrying-in/carrying-out lanes 20a and 20b of each of two pieces of wafer cleaning equipment 39a and 39b. The fourth embodiment is basically the same as the third embodiment with the exception that a vacant cassette carrying-out lane 25 is replaced by a vacant-cassette stocker 41 (41a and 41b).
Referring to FIG. 24, the flow of cassettes in the wafer cleaning module is described below.
Step 201: Four wafer cassettes are put on the module carrying-in lane 11. (One through four cassettes can be put on it.)
Steps 202 and 203: The robot 8 carries these cassettes either to the cassette stocker 16 or directly to the carrying-in/carrying-out lane 20b of the wafer cleaning equipment 39b. Four vacant cassettes from which wafers have been removed in the wafer cleaning equipment 39b are carried to the vacant-cassette stocker 41b.
Steps 204 and 205: There are no steps corresponding to the steps 204 and 205 of the third embodiment, but at the wafer cleaning equipment 39b, cleaned wafers are inserted into the vacant cassettes and the cassettes are carried to the carrying-in/carrying-out lane 20b.
Step 206: The robot 8 carries these cassettes containing cleaned wafers either to the cassette stocker 16 or directly to the module carrying-out lane 13. Cassettes which are carried into the cassette stocker 16 are carried to the module carrying-out lane 13 at an appropriate time by the robot 8.
Step 207: The cassettes containing cleaned wafers are carried out from the module carrying-out lane 13.
Operations similar to the above are also performed for the wafer cleaning equipment 39a.
As described above, the present invention makes it possible to perform full ID-card management inside equipment. The present invention also makes it possible to achieve a reduction in equipment sizes, and also high efficiency factory automation. Furthermore, the carrying path of cases can be simplified and the number of carrying means such as robots can be reduced. Besides, it is possible to arrange a plurality of items of semiconductor processing equipment in parallel so that cases can be carried to/from only one side of the equipment, thus the number of case carrying means can be reduced and a size reduction can be achieved for modules to achieve the factory automation. | Semiconductor processing equipment includes an ID-card removing robot, an ID-card stocking device, and an ID-card attaching robot so that the management of ID cards is performed inside the equipment. Thus, the present invention makes it possible to reduce equipment size and achieve highly efficient factory automation. Furthermore, in a semiconductor processing equipment module according to the present invention, each item of semiconductor processing equipment has its own ID-card stocking device. As a result, the number of case carriers can be reduced and a space reduction with increased factory automation can be easily realized. | 8 |
The current application claims a foreign priority to application number 104103580 filed on Feb. 3, 2015 in Taiwan
BACKGROUND OF THE INVENTION
1. Technical Field
The present invention relates generally to an optical system, and more particularly to a compact optical image capturing system for an electronic device.
2. Description of Related Art
In recent years, with the rise of portable electronic devices having camera functionalities, the demand for an optical image capturing system is raised gradually. The image sensing device of ordinary photographing camera is commonly selected from charge coupled device (CCD) or complementary metal-oxide semiconductor sensor (CMOS Sensor). In addition, as advanced semiconductor manufacturing technology enables the minimization of pixel size of the image sensing device, the development of the optical image capturing system towards the field of high pixels. Therefore, the requirement for high imaging quality is rapidly raised.
The conventional optical system of the portable electronic device usually has a three or four-piece lens. However, the optical system is asked to take pictures in a dark environment, in other words, the optical system is asked to have a large aperture. An optical system with large aperture usually has several problems, such as large aberration, poor image quality at periphery of the image, and hard to manufacture. In addition, an optical system of wide-angle usually has large distortion. Therefore, the conventional optical system provides high optical performance as required.
It is an important issue to increase the quantity of light entering the lens and the angle of field of the lens. In addition, the modern lens is also asked to have several characters, including high pixels, high image quality, small in size, and high optical performance.
BRIEF SUMMARY OF THE INVENTION
The aspect of embodiment of the present disclosure directs to an optical image capturing system and an optical image capturing lens which use combination of refractive powers, convex and concave surfaces of five-piece optical lenses (the convex or concave surface in the disclosure denotes the geometrical shape of an image-side surface or an object-side surface of each lens on an optical axis) to increase the quantity of incoming light of the optical image capturing system, and to improve imaging quality for image formation, so as to be applied to minimized electronic products.
The term and its definition to the lens parameter in the embodiment of the present are shown as below for further reference.
The lens parameter related to a length or a height in the lens element:
A height for image formation of the optical image capturing system is denoted by HOI. A height of the optical image capturing system is denoted by HOS. A distance from the object-side surface of the first lens element to the image-side surface of the fifth lens element is denoted by InTL. A distance from the image-side surface of the fifth lens to the image plane is denoted by InB. InTL+InB=HOS. A distance from the first lens element to the second lens element is denoted by IN 12 (instance). A central thickness of the first lens element of the optical image capturing system on the optical axis is denoted by TP 1 (instance).
The lens parameter related to a material in the lens:
An Abbe number of the first lens element in the optical image capturing system is denoted by NA 1 (instance). A refractive index of the first lens element is denoted by Nd 1 (instance).
The lens parameter related to a view angle in the lens:
A view angle is denoted by AF. Half of the view angle is denoted by HAF. A major light angle is denoted by MRA.
The lens parameter related to exit/entrance pupil in the lens
An entrance pupil diameter of the optical image capturing system is denoted by HEP.
The lens parameter related to a depth of the lens shape
A distance in parallel with an optical axis from a maximum effective semi diameter position to an axial point on the object-side surface of the fifth lens is denoted by InRS 51 (instance). A distance in parallel with an optical axis from a maximum effective semi diameter position to an axial point on the image-side surface of the fifth lens is denoted by InRS 52 (instance).
The lens parameter related to the lens shape:
A critical point C is a tangent point on a surface of a specific lens, and the tangent point is tangent to a plane perpendicular to the optical axis and the tangent point cannot be a crossover point on the optical axis. To follow the past, a distance perpendicular to the optical axis between a critical point C 41 on the object-side surface of the fourth lens and the optical axis is HVT 41 (instance). A distance perpendicular to the optical axis between a critical point C 51 on the object-side surface of the fifth lens and the optical axis is HVT 51 (instance). A distance perpendicular to the optical axis between a critical point C 52 on the image-side surface of the fifth lens and the optical axis is HVT 52 (instance). The object-side surface of the fifth lens has one inflection point IF 511 which is nearest to the optical axis, and the sinkage value of the inflection point IF 511 is denoted by SGI 511 . A distance perpendicular to the optical axis between the inflection point IF 511 and the optical axis is HIF 511 (instance). The image-side surface of the fifth lens has one inflection point IF 521 which is nearest to the optical axis, and the sinkage value of the inflection point IF 521 is denoted by SGI 521 (instance). A distance perpendicular to the optical axis between the inflection point IF 521 and the optical axis is HIF 521 (instance). The object-side surface of the fifth lens has one inflection point IF 512 which is the second nearest to the optical axis, and the sinkage value of the inflection point IF 512 is denoted by SGI 512 (instance). A distance perpendicular to the optical axis between the inflection point IF 512 and the optical axis is HIF 512 (instance). The image-side surface of the fifth lens has one inflection point IF 522 which is the second nearest to the optical axis, and the sinkage value of the inflection point IF 522 is denoted by SGI 522 (instance). A distance perpendicular to the optical axis between the inflection point IF 522 and the optical axis is HIF 522 (instance).
The lens element parameter related to an aberration:
Optical distortion for image formation in the optical image capturing system is denoted by ODT. TV distortion for image formation in the optical image capturing system is denoted by TDT. Further, the range of the aberration offset for the view of image formation may be limited to 50%-100% field. An offset of the spherical aberration is denoted by DFS. An offset of the coma aberration is denoted by DFC.
The present invention provides an optical image capturing system, in which the fifth lens is provided with an inflection point at the object-side surface or at the image-side surface to adjust the incident angle of each view field and modify the ODT and the TDT. In addition, the surfaces of the fifth lens are capable of modifying the optical path to improve the imagining quality.
The optical image capturing system of the present invention includes a first lens, a second lens, a third lens, a fourth lens, and a fifth lens in order along an optical axis from an object side to an image side. These five lenses have refractive power. Both the object-side surface and the image-side surface of the fifth lens are aspheric surfaces. The optical image capturing system satisfies:
1.2 ≦f /HEP≦6.0; 0.5≦HOS/ f ≦5.0; 0<Σ|InRS|/InTL≦3;
where f is a focal length of the optical image capturing system; HEP is an entrance pupil diameter of the optical image capturing system; HOS is a distance in parallel with the optical axis from an object-side surface of the first lens to the image plane; Σ|InRS| is a sum of InRSO and InRSI, where InRSO is a sum of absolute values of the displacements in parallel with the optical axis of each lens with refractive power from the central point on the object-side surface to the point at the maximum effective semi diameter of the object-side surface, and InRSI is a sum of absolute values of the displacements in parallel with the optical axis of each lens with refractive power from the central point on the image-side surface to the point at the maximum effective semi diameter of the image-side surface; and InTL is a distance in parallel with the optical axis between the object-side surface of the first lens and the image-side surface of the fourth lens.
The present invention further provides an optical image capturing system, including a first lens, a second lens, a third lens, a fourth lens, and a fifth lens in order along an optical axis from an object side to an image side. The first lens has refractive power. The second lens has refractive power, and the third and the fourth lenses have refractive power. The fifth lens has negative refractive power, and both an object-side surface and an image-side surface thereof are aspheric surfaces. The optical image capturing system satisfies:
1.2 ≦f /HEP≦6.0; 0.5≦HOS/ f ≦5.0; 0<Σ|InRS|/InTL≦3; |TDT|<60%; and |ODT|≦50%;
where f is a focal length of the optical image capturing system; HEP is an entrance pupil diameter of the optical image capturing system; HOS is a distance in parallel with the optical axis between an object-side surface, which face the object side, of the first lens and the image plane; HAF is a half of the view angle of the optical image capturing system; TDT is a TV distortion; ODT is an optical distortion; Σ|InRS| is a sum of InRSO and InRSI, where InRSO is a sum of absolute values of the displacements in parallel with the optical axis of each lens with refractive power from the central point on the object-side surface to the point at the maximum effective semi diameter of the object-side surface, and InRSI is a sum of absolute values of the displacements in parallel with the optical axis of each lens with refractive power from the central point on the image-side surface to the point at the maximum effective semi diameter of the image-side surface; and InTL is a distance in parallel with the optical axis between the object-side surface of the first lens and the image-side surface of the fourth lens.
The present invention further provides an optical image capturing system, including a first lens, a second lens, a third lens, a fourth lens, and a fifth lens in order along an optical axis from an object side to an image side. At least two of these five lenses each has at least an inflection point on at least a surface thereof. The first lens has positive refractive power, and both an object-side surface and an image-side surface thereof are aspheric surfaces. The second and the third lens have refractive power, and the fourth lens has positive refractive power. The fifth lens has negative refractive power, and both an object-side surface and an image-side surface thereof are aspheric surfaces. The optical image capturing system satisfies:
1.2 ≦f /HEP≦3.0; 0.5≦HOS/ f ≦3.0; 0≦Σ|InRS|/InTL≦3; |TDT|<60%; and |ODT|≦50%;
where f is a focal length of the optical image capturing system; HEP is an entrance pupil diameter of the optical image capturing system; HOS is a distance in parallel with the optical axis between an object-side surface, which face the object side, of the first lens and the image plane; HAF is a half of the view angle of the optical image capturing system; TDT is a TV distortion; ODT is an optical distortion; Σ|InRS| is a sum of InRSO and InRSI, where InRSO is a sum of absolute values of the displacements in parallel with the optical axis of each lens with refractive power from the central point on the object-side surface to the point at the maximum effective semi diameter of the object-side surface, and InRSI is a sum of absolute values of the displacements in parallel with the optical axis of each lens with refractive power from the central point on the image-side surface to the point at the maximum effective semi diameter of the image-side surface; and InTL is a distance in parallel with the optical axis between the object-side surface of the first lens and the image-side surface of the fourth lens.
In an embodiment, the optical image capturing system further includes an image sensor with a size less than 1/1.2″ in diagonal, and the preferred size is 1/2.3″, and a pixel less than 1.4 μm. A preferable pixel size of the image sensor is less than 1.2 μm, and more preferable pixel size is less than 0.9 μm. A 16:9 image sensor is available for the optical image capturing system of the present invention.
In an embodiment, the optical image capturing system of the present invention is available to high-quality (4K 2K, so called UHD and QHD) recording, and provides high quality of image.
In an embodiment, a height of the optical image capturing system (HOS) can be reduced while |f 1 |>f 5 .
In an embodiment, when the lenses satisfy |f 2 |+|f 3 |+|f 4 |>|f 1 |+|f 5 |, at least one of the lenses from the second lens to the fourth lens could have weak positive refractive power or weak negative refractive power. The weak refractive power indicates that an absolute value of the focal length is greater than 10. When at least one of the lenses from the second lens to the fourth lens could have weak positive refractive power, it may share the positive refractive power of the first lens, and on the contrary, when at least one of the lenses from the second lens to the fourth lens could have weak negative refractive power, it may finely modify the aberration of the system.
In an embodiment, the fifth lens has negative refractive power, and an image-side surface thereof is concave, it may reduce back focal length and size. Besides, the fifth lens has at least an inflection point on a surface thereof, which may reduce an incident angle of the light of an off-axis field of view and modify the aberration of the off-axis field of view. It is preferable that both surfaces of the fifth lens have at least an inflection point on a surface thereof.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
The present invention will be best understood by referring to the following detailed description of some illustrative embodiments in conjunction with the accompanying drawings, in which
FIG. 1A is a schematic diagram of a first preferred embodiment of the present invention;
FIG. 1B shows curve diagrams of longitudinal spherical aberration, astigmatic field, and optical distortion of the optical image capturing system in the order from left to right of the first embodiment of the present application;
FIG. 1C shows a curve diagram of TV distortion of the optical image capturing system of the first embodiment of the present application;
FIG. 2A is a schematic diagram of a second preferred embodiment of the present invention;
FIG. 2B shows curve diagrams of longitudinal spherical aberration, astigmatic field, and optical distortion of the optical image capturing system in the order from left to right of the second embodiment of the present application;
FIG. 2C shows a curve diagram of TV distortion of the optical image capturing system of the second embodiment of the present application;
FIG. 3A is a schematic diagram of a third preferred embodiment of the present invention;
FIG. 3B shows curve diagrams of longitudinal spherical aberration, astigmatic field, and optical distortion of the optical image capturing system in the order from left to right of the third embodiment of the present application;
FIG. 3C shows a curve diagram of TV distortion of the optical image capturing system of the third embodiment of the present application;
FIG. 4A is a schematic diagram of a fourth preferred embodiment of the present invention;
FIG. 4B shows curve diagrams of longitudinal spherical aberration, astigmatic field, and optical distortion of the optical image capturing system in the order from left to right of the fourth embodiment of the present application;
FIG. 4C shows a curve diagram of TV distortion of the optical image capturing system of the fourth embodiment of the present application;
FIG. 5A is a schematic diagram of a fifth preferred embodiment of the present invention;
FIG. 5B shows curve diagrams of longitudinal spherical aberration, astigmatic field, and optical distortion of the optical image capturing system in the order from left to right of the fifth embodiment of the present application;
FIG. 5C shows a curve diagram of TV distortion of the optical image capturing system of the fifth embodiment of the present application;
FIG. 6A is a schematic diagram of a sixth preferred embodiment of the present invention;
FIG. 6B shows curve diagrams of longitudinal spherical aberration, astigmatic field, and optical distortion of the optical image capturing system in the order from left to right of the sixth embodiment of the present application; and
FIG. 6C shows a curve diagram of TV distortion of the optical image capturing system of the sixth embodiment of the present application.
DETAILED DESCRIPTION OF THE INVENTION
An optical image capturing system of the present invention includes a first lens, a second lens, a third lens, a forth lens, and a fifth lens from an object side to an image side with refractive power. The optical image capturing system further is provided with an image sensor at an image plane.
The optical image capturing system works in three wavelengths, including 486.1 nm, 510 nm, 587.5 nm, and 656.2 nm, wherein 587.5 nm is the main reference wavelength, and 555 nm is the reference wavelength for obtaining the technical characters.
The optical image capturing system of the present invention satisfies 0.5≦ΣPPR/|ΣNPR|≦2.5, and a preferable range is 1≦ΣPPR/|ΣNPR|≦2.0, where PPR is a ratio of the focal length f of the optical image capturing system to a focal length fp of each of lenses with positive refractive power; NPR is a ratio of the focal length f of the optical image capturing system to a focal length fn of each of lenses with negative refractive power; ΣPPR is a sum of the PPRs of each positive lens; and ΣNPR is a sum of the NPRs of each negative lens. It is helpful to control of an entire refractive power and an entire length of the optical image capturing system.
HOS is a height of the optical image capturing system, and when the ratio of HOS/f approaches to 1, it is helpful to decrease of size and increase of imaging quality.
In an embodiment, the optical image capturing system of the present invention satisfies 0<ΣPP≦200 and f 1 /ΣPP≦0.85, where ΣPP is a sum of a focal length fp of each lens with positive refractive power, and ΣNP is a sum of a focal length fn of each lens with negative refractive power. It is helpful to control of focusing capacity of the system and redistribution of the positive refractive powers of the system to avoid the significant aberration in early time. The optical image capturing system further satisfies ΣNP<−0.1 and f 5 /ΣNP≦0.85, which is helpful to control of an entire refractive power and an entire length of the optical image capturing system.
The first lens has positive refractive power, and an object-side surface, which faces the object side, thereof is convex. It may modify the positive refractive power of the first lens as well as shorten the entire length of the system.
The second lens has negative refractive power, which may correct the aberration of the first lens.
The third lens has positive refractive power, which may share the positive refractive power of the first lens. It may share the positive refractive power of the first lens to reduce an increase of the aberration and reduce a sensitivity of the system.
The fourth lens has positive refractive power, and an image-side surface thereof, which faces the image side, is convex. It may share the positive refractive power of the first lens to reduce an increase of the aberration and reduce a sensitivity of the system.
The fifth lens has negative refractive power, and an image-side surface thereof, which faces the image side, is concave. It may shorten a rear focal length to reduce the size of the system. In addition, the fifth lens is provided with at least an inflection point on at least a surface to reduce an incident angle of the light of an off-axis field of view and modify the aberration of the off-axis field of view. It is preferable that each surface, the object-side surface and the image-side surface, of the fifth lens has at least an inflection point.
The image sensor is provided on the image plane. The optical image capturing system of the present invention satisfies HOS/HOI≦3 and 0.5≦HOS/f≦5.0, and a preferable range is 1≦HOS/HOI≦2.5 and 1≦HOS/f≦2, where HOI is height for image formation of the optical image capturing system, i.e., the maximum image height, and HOS is a height of the optical image capturing system, i.e. a distance on the optical axis between the object-side surface of the first lens and the image plane. It is helpful to reduction of size of the system for used in compact cameras.
The optical image capturing system of the present invention further is provided with an aperture to increase image quality.
In the optical image capturing system of the present invention, the aperture could be a front aperture or a middle aperture, wherein the front aperture is provided between the object and the first lens, and the middle is provided between the first lens and the image plane. The front aperture provides a long distance between an exit pupil of the system and the image plane, which allows more elements to be installed. The middle could enlarge a view angle of view of the system and increase the efficiency of the image sensor. The optical image capturing system satisfies 0.5≦InS/HOS≦1.1, and a preferable range is 0.8≦InS/HOS≦1, where InS is a distance between the aperture and the image plane. It is helpful to size reduction and wide angle.
The optical image capturing system of the present invention satisfies 0.45≦ΣTP/InTL≦0.95, where InTL is a distance between the object-side surface of the first lens and the image-side surface of the fifth lens, and ΣTP is a sum of central thicknesses of the lenses on the optical axis. It is helpful to the contrast of image and yield rate of manufacture, and provides a suitable back focal length for installation of other elements.
The optical image capturing system of the present invention satisfies 0.1≦|R 1 /R 2 |≦5, and a preferable range is 0.1≦|R 1 /R 2 |≦4, where R 1 is a radius of curvature of the object-side surface of the first lens, and R 2 is a radius of curvature of the image-side surface of the first lens. It provides the first lens with a suitable positive refractive power to reduce the increase rate of the spherical aberration.
The optical image capturing system of the present invention satisfies −200<(R 9 −R 10 )/(R 9 +R 10 )<30, where R 9 is a radius of curvature of the object-side surface of the fifth lens, and R 10 is a radius of curvature of the image-side surface of the fifth lens. It may modify the astigmatic field curvature.
The optical image capturing system of the present invention satisfies 0<IN 12 /f≦2.0, and a preferable range is 0.01≦IN 12 /f≦0.25, where IN 12 is a distance on the optical axis between the first lens and the second lens. It may correct chromatic aberration and improve the performance.
The optical image capturing system of the present invention satisfies 0<(TP 1 +IN 12 )/TP 2 ≦10, where TP 1 is a central thickness of the first lens on the optical axis, and TP 2 is a central thickness of the second lens on the optical axis. It may control the sensitivity of manufacture of the system and improve the performance.
The optical image capturing system of the present invention satisfies 0<(TP 5 +IN 45 )/TP 4 ≦10, where TP 4 is a central thickness of the fourth lens on the optical axis, TP 5 is a central thickness of the fifth lens on the optical axis, and N 45 is a distance between the fourth lens and the fifth lens. It may control the sensitivity of manufacture of the system and improve the performance.
The optical image capturing system of the present invention satisfies 0.1≦(TP 2 +TP 3 +TP 4 )/ΣTP≦0.9, and a preferable range is 0.4≦(TP 2 +TP 3 +TP 4 )/ΣTP≦0.8, where TP 2 is a central thickness of the second lens on the optical axis, TP 3 is a central thickness of the third lens on the optical axis, TP 4 is a central thickness of the fourth lens on the optical axis, TP 5 is a central thickness of the fifth lens on the optical axis, and ΣTP is a sum of the central thicknesses of all the lenses on the optical axis. It may finely modify the aberration of the incident rays and reduce the height of the system.
The optical image capturing system of the present invention satisfies 0≦|InRS 11 |+|InRS 12 |≦2 mm; and 1.01≦(|InRS 11 |+TP 1 +|InRS 12 |)/TP 1 ≦3, where InRS 11 is a displacement in parallel with the optical axis from a point on the object-side surface of the first lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the object-side surface of the first lens, wherein InRS 11 is positive while the displacement is toward the image side, and InRS 11 is negative while the displacement is toward the object side; InRS 12 is a displacement in parallel with the optical axis from a point on the image-side surface of the first lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the image-side surface of the first lens; and TP 1 is a central thickness of the first lens on the optical axis. It may control a ratio of the central thickness of the first lens and the effective semi diameter thickness (thickness ratio) to increase the yield rate of manufacture.
The optical image capturing system of the present invention satisfies 0≦|InRS 21 |+|InRS 22 |≦2 mm; and 1.01≦(|InRS 21 |+TP 2 +|InRS 22 |)/TP 2 ≦5, where InRS 21 is a displacement in parallel with the optical axis from a point on the object-side surface of the second lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the object-side surface of the first lens; InRS 22 is a displacement in parallel with the optical axis from a point on the image-side surface of the second lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the image-side surface of the second lens; and TP 2 is a central thickness of the second lens on the optical axis. It may control a ratio of the central thickness of the second lens and the effective semi diameter thickness (thickness ratio) to increase the yield rate of manufacture.
The optical image capturing system of the present invention satisfies 0≦|InRS 31 |+|InRS 32 |≦2 mm; and 1.01≦(|InRS 31 |+TP 3 +|InRS 32 |)/TP 3 ≦10, where InRS 31 is a displacement in parallel with the optical axis from a point on the object-side surface of the third lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the object-side surface of the first lens; InRS 32 is a displacement in parallel with the optical axis from a point on the image-side surface of the third lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the image-side surface of the third lens; and TP 3 is a central thickness of the third lens on the optical axis. It may control a ratio of the central thickness of the third lens and the effective semi diameter thickness (thickness ratio) to increase the yield rate of manufacture.
The optical image capturing system of the present invention satisfies 0≦|InRS 41 |+|InRS 42 |≦2 mm; and 1.01≦(|InRS 41 |+TP 4 +|InRS 42 |)/TP 4 ≦10, where InRS 41 is a displacement in parallel with the optical axis from a point on the object-side surface of the fourth lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the object-side surface of the first lens; InRS 42 is a displacement in parallel with the optical axis from a point on the image-side surface of the fourth lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the image-side surface of the fourth lens; and TP 4 is a central thickness of the fourth lens on the optical axis. It may control a ratio of the central thickness of the fourth lens and the effective semi diameter thickness (thickness ratio) to increase the yield rate of manufacture.
The optical image capturing system of the present invention satisfies 0≦|InRS 51 |+|InRS 52 |≦3 mm; and 1.01≦(|InRS 51 |+TP 5 +|InRS 52 |)/TP 5 ≦20, where InRS 51 is a displacement in parallel with the optical axis from a point on the object-side surface of the fifth lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the object-side surface of the first lens; InRS 52 is a displacement in parallel with the optical axis from a point on the image-side surface of the fifth lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the image-side surface of the fifth lens; and TP 5 is a central thickness of the fifth lens on the optical axis. It may control a ratio of the central thickness of the fifth lens and the effective semi diameter thickness (thickness ratio) to increase the yield rate of manufacture.
The optical image capturing system of the present invention satisfies 0<Σ|InRS|≦15 mm, where Σ|InRS| is of an sum of absolute values of the displacements in parallel with the optical axis of each lens with refractive power from the central point to the point at the maximum effective semi diameter, i.e. Σ|InRS|=InRSO+InRSI while InRSO is of a sum of absolute values of the displacements in parallel with the optical axis of each lens with refractive power from the central point on the object-side surface to the point at the maximum effective semi diameter of the object-side surface, i.e. InRSO=|InRS 11 |+|InRS 21 |+|InRS 31 |+|InRS 41 |+|InRS 51 | and InRSI is of a sum of absolute values of the displacements in parallel with the optical axis of each lens with refractive power from the central point on the image-side surface to the point at the maximum effective semi diameter of the image-side surface, i.e. InRSI=|InRS 12 |+|InRS 22 |+|InRS 32 |+|InRS 42 |+|InRS 52 |. It may increase the capability of modifying the off-axis view field aberration of the system.
The optical image capturing system of the present invention satisfies 0<Σ|InRS|/InTL≦3 and 0<Σ|InRS|/HOS≦2. It may reduce the total height of the system as well as efficiently increase the capability of modifying the off-axis view field aberration of the system.
The optical image capturing system of the present invention satisfies 0<|InRS 41 |+|InRS 42 |+|InRS 51 |+|InRS 52 |≦5 mm; 0<(|InRS 41 |+|InRS 42 |+|InRS 51 |+|InRS 52 |)/InTL≦2; and 0<(|InRS 41 |+|InRS 42 |+|InRS 51 |+|InRS 52 |)/HOS≦2. It could increase the yield rate of manufacture of the two lenses, which are the first and the second closest to the image side, and increase the capability of modifying the off-axis view field aberration of the system.
The optical image capturing system of the present invention satisfies HVT 41 ≧0 mm and HVT 42 ≧0 mm, where HVT 41 a distance perpendicular to the optical axis between the inflection point on the object-side surface of the fourth lens and the optical axis; and HVT 42 a distance perpendicular to the optical axis between the inflection point on the image-side surface of the fourth lens and the optical axis. It may efficiently modify the off-axis view field aberration of the system.
The optical image capturing system of the present invention satisfies HVT 51 ≧0 mm and HVT 52 ≧0 mm, where HVT 51 a distance perpendicular to the optical axis between the inflection point on the object-side surface of the fifth lens and the optical axis; and HVT 52 a distance perpendicular to the optical axis between the inflection point on the image-side surface of the fifth lens and the optical axis. It may efficiently modify the off-axis view field aberration of the system.
The optical image capturing system of the present invention satisfies 0.2≦HVT 52 /HOI≦0.9, and preferable is 0.3≦HVT 52 /HOI≦0.8. It is helpful to correction of the aberration of the peripheral view field.
The optical image capturing system of the present invention satisfies 0≦HVT 52 /HOS≦0.5, and preferable is 0.2≦HVT 52 /HOS≦0.45. It is helpful to correction of the aberration of the peripheral view field.
In an embodiment, the lenses of high Abbe number and the lenses of low Abbe number are arranged in an interlaced arrangement that could be helpful to correction of aberration of the system.
An equation of aspheric surface is
z=ch 2 /[1+[1( k+ 1) c 2 h 2 ] 0.5 ]+A 4 h 4 +A 6 h 6 +A 8 h 8 +A 10 h 10 +A 12 h 12 +A 14 h 14 +A 16 h 16 +A 18 h 18 +A 20 h 20 (1)
where z is a depression of the aspheric surface; k is conic constant; c is reciprocal of radius of curvature; and A4, A6, A8, A10, A12, A14, A16, A18, and A20 are high-order aspheric coefficients.
In the optical image capturing system, the lenses could be made of plastic or glass. The plastic lenses may reduce the weight and lower the cost of the system, and the glass lenses may control the thermal effect and enlarge the space for arrangement of refractive power of the system. In addition, the opposite surfaces (object-side surface and image-side surface) of the first to the fifth lenses could be aspheric that can obtain more control parameters to reduce aberration. The number of aspheric glass lenses could be less than the conventional spherical glass lenses that is helpful to reduction of the height of the system.
When the lens has a convex surface, which means that the surface is convex around a position, through which the optical axis passes, and when the lens has a concave surface, which means that the surface is concave around a position, through which the optical axis passes.
The optical image capturing system of the present invention further is provided with a diaphragm to increase image quality.
In the optical image capturing system, the diaphragm could be a front diaphragm or a middle diaphragm, wherein the front diaphragm is provided between the object and the first lens, and the middle is provided between the first lens and the image plane. The front diaphragm provides a long distance between an exit pupil of the system and the image plane, which allows more elements to be installed. The middle diaphragm could enlarge a view angle of view of the system and increase the efficiency of the image sensor. The middle diaphragm is helpful to size reduction and wide angle.
The optical image capturing system of the present invention could be applied in dynamic focusing optical system. It is superior in correction of aberration and high imaging quality so that it could be allied in lots of fields.
We provide several embodiments in conjunction with the accompanying drawings for the best understanding, which are:
First Embodiment
As shown in FIG. 1A and FIG. 1B , an optical image capturing system 100 of the first preferred embodiment of the present invention includes, along an optical axis from an object side to an image side, an aperture 100 , a first lens 110 , a second lens 120 , a third lens 130 , a fourth lens 140 , a fifth lens 150 , an infrared rays filter 170 , an image plane 180 , and an image sensor 190 .
The first lens 110 has positive refractive power, and is made of plastic. An object-side surface 112 thereof, which faces the object side, is a convex aspheric surface, and an image-side surface 114 thereof, which faces the image side, is a concave aspheric surface, and the image-side surface has an inflection point. The first lens 110 satisfies SGI 121 =0.0387148 mm and |SGI 121 |/(|SGI 121 |+TP 1 )=0.061775374, where SGI 121 is a displacement in parallel with the optical axis from a point on the image-side surface of the first lens, through which the optical axis passes, to the inflection point on the image-side surface, which is the closest to the optical axis.
The first lens 110 further satisfies HIF 121 =0.61351 mm and HIF 121 /HOI=0.209139253, where HIF 121 is a displacement perpendicular to the optical axis from a point on the image-side surface of the first lens, through which the optical axis passes, to the inflection point, which is the closest to the optical axis.
The second lens 120 has negative refractive power, and is made of plastic. An object-side surface 122 thereof, which faces the object side, is a concave aspheric surface, and an image-side surface 124 thereof, which faces the image side, is a convex aspheric surface, and the image-side surface 124 has an inflection point. The second lens 120 satisfies SGI 221 =−0.0657553 mm and |SGI 221 |/(|SGI 221 |+TP 2 )=0.176581512, where SGI 221 is a displacement in parallel with the optical axis from a point on the image-side surface of the second lens, through which the optical axis passes, to the inflection point on the image-side surface, which is the closest to the optical axis.
The second lens further satisfies HIF 221 =0.84667 mm and HIF 221 /HOI=0.288621101, where HIF 221 is a displacement perpendicular to the optical axis from a point on the image-side surface of the second lens, through which the optical axis passes, to the inflection point, which is the closest to the optical axis.
The third lens 130 has negative refractive power, and is made of plastic. An object-side surface 132 , which faces the object side, is a concave aspheric surface, and an image-side surface 134 , which faces the image side, is a convex aspheric surface, and each of them has two inflection points. The third lens 130 satisfies SGI 311 =−0.341027 mm; SGI 321 =−0.231534 mm and |SGI 311 |/(|SGI 311 |+TP 3 )=0.525237108 and |SGI 321 |/(|SGI 321 |+TP 3 )=0.428934269, where SGI 311 is a displacement in parallel with the optical axis, from a point on the object-side surface of the third lens, through which the optical axis passes, to the inflection point on the object-side surface, which is the closest to the optical axis, and SGI 321 is a displacement in parallel with the optical axis, from a point on the image-side surface of the third lens, through which the optical axis passes, to the inflection point on the image-side surface, which is the closest to the optical axis.
The third lens 130 satisfies SGI 312 =−0.376807 mm; SGI 322 =−0.382162 mm; |SGI 312 |/(|SGI 312 |+TP 5 )=0.550033428; |SGI 322 |/(|SGI 322 |+TP 3 )=0.55352345, where SGI 312 is a displacement in parallel with the optical axis, from a point on the object-side surface of the third lens, through which the optical axis passes, to the inflection point on the object-side surface, which is the second closest to the optical axis, and SGI 322 is a displacement in parallel with the optical axis, from a point on the image-side surface of the third lens, through which the optical axis passes, to the inflection point on the image-side surface, which is the second closest to the optical axis.
The third lens 130 further satisfies HIF 311 =0.987648 mm; HIF 321 =0.805604 mm; HIF 311 /HOI=0.336679052; and HIF 321 /HOI=0.274622124, where HIF 311 is a distance perpendicular to the optical axis between the inflection point on the object-side surface of the third lens, which is the closest to the optical axis, and the optical axis, and HIF 321 is a distance perpendicular to the optical axis between the inflection point on the image-side surface of the third lens, which is the closest to the optical axis, and the optical axis.
The third lens 130 further satisfies HIF 312 =1.0493 mm; HIF 322 =1.17741 mm; HIF 312 /HOI=0.357695585; and HIF 322 /HOI=0.401366968, where HIF 312 is a distance perpendicular to the optical axis between the inflection point on the object-side surface of the third lens, which is the second the closest to the optical axis, and the optical axis, and HIF 322 is a distance perpendicular to the optical axis, between the inflection point on the image-side surface of the third lens, which is the second the closest to the optical axis, and the optical axis.
The fourth lens 140 has positive refractive power, and is made of plastic. Both an object-side surface 142 , which faces the object side, and an image-side surface 144 , which faces the image side, thereof are convex aspheric surfaces, and the object-side surface 142 has an inflection point. The fourth lens 140 satisfies SGI 411 =0.0687683 mm and |SGI 411 |/(|SGI 411 |+TP 4 )=0.118221297, where SGI 411 is a displacement in parallel with the optical axis from a point on the object-side surface of the fourth lens, through which the optical axis passes, to the inflection point on the object-side surface, which is the closest to the optical axis.
The fourth lens 140 further satisfies HIF 411 =0.645213 mm and HIF 411 /HOI=0.21994648, where HIF 411 is a distance perpendicular to the optical axis between the inflection point on the object-side surface of the fourth lens, which is the closest to the optical axis, and the optical axis.
The fifth lens 150 has negative refractive power, and is made of plastic. Both an object-side surface 152 , which faces the object side, and an image-side surface 154 , which faces the image side, thereof are concave aspheric surfaces. The object-side surface 152 has three inflection points, and the image-side surface 154 has an inflection point. The fifth lens 150 satisfies SGI 511 =−0.236079 mm; SGI 521 =0.023266 mm; |SGI 511 |/(|SGI 511 |+TP 5 )=0.418297214; and |SGI 521 |/(|SGI 521 |+TP 5 )=0.066177809, where SGI 511 is a displacement in parallel with the optical axis, from a point on the object-side surface of the fifth lens, through which the optical axis passes, to the inflection point on the object-side surface, which is the closest to the optical axis, and SGI 521 is a displacement in parallel with the optical axis, from a point on the image-side surface of the fifth lens, through which the optical axis passes, to the inflection point on the image-side surface, which is the closest to the optical axis.
The fifth lens 150 further satisfies SGI 512 =−0.325042 mm and |SGI 512 |/(|SGI 512 |+TP 5 )=0.497505143, where SGI 512 is a displacement in parallel with the optical axis, from a point on the object-side surface of the fifth lens, through which the optical axis passes, to the inflection point on the object-side surface, which is the second closest to the optical axis.
The fifth lens 150 further satisfies SGI 513 =−0.538131 mm; and |SGI 513 |/(|SGI 513 |+TP 5 )=0.621087839, where SGI 513 is a displacement in parallel with the optical axis, from a point on the object-side surface of the fifth lens, through which the optical axis passes, to the inflection point on the object-side surface, which is the third closest to the optical axis.
The fifth lens 150 further satisfies HIF 511 =1.21551 mm; HIF 521 =0.575738 mm; HIF 511 /HOI=0.414354866; and HIF 521 /HOI=0.196263167, where HIF 511 is a distance perpendicular to the optical axis between the inflection point on the object-side surface of the fifth lens, which is the closest to the optical axis, and the optical axis, and HIF 521 is a distance perpendicular to the optical axis between the inflection point on the image-side surface of the fifth lens, which is the closest to the optical axis, and the optical axis.
The fifth lens 150 further satisfies HIF 512 =1.49061 mm and HIF 512 /HOI=0.508133629, where HIF 512 is a distance perpendicular to the optical axis between the inflection point on the object-side surface of the fifth lens, which is the second the closest to the optical axis, and the optical axis.
The fifth lens 150 further satisfies HIF 513 =2.00664 mm and HIF 513 /HOI=0.684042952, where HIF 513 is a distance perpendicular to the optical axis between the inflection point on the object-side surface of the fifth lens, which is the third closest to the optical axis, and the optical axis.
The infrared rays filter 170 is made of glass, and between the fifth lens 150 and the image plane 180 . The infrared rays filter 170 gives no contribution to the focal length of the system.
The optical image capturing system of the first preferred embodiment has the following parameters, which are f=3.73172 mm; f/HEP=2.05; and HAF=37.5 degrees and tan(HAF)=0.7673, where f is a focal length of the system; HAF is a half of the maximum field angle; and HEP is an entrance pupil diameter.
The parameters of the lenses of the first preferred embodiment are f 1 =3.7751 mm; |f/f 1 |=0.9885; f 5 =−3.6601 mm; |f 1 |>f 5 ; and |f 1 /f 5 |=1.0314, where f 1 is a focal length of the first lens 110 ; and f 5 is a focal length of the fifth lens 150 .
The first preferred embodiment further satisfies |f 2 |+|f 3 |+|f 4 |=77.3594 mm; |f 1 |+|f 5 |=7.4352 mm; and |f 2 |+|f 3 |+|f 4 |>|f 1 |+|f 5 |, where f 2 is a focal length of the second lens 120 ; f 3 is a focal length of the third lens 130 ; and f 4 is a focal length of the fourth lens 140 .
The optical image capturing system of the first preferred embodiment further satisfies ΣPPR=f/f 1 +f/f 4 =1.9785; ΣNPR=f/f 2 +f/f 3 +f/f 5 =−1.2901; ΣPPR/|ΣNPR|=1.5336; |f/f 1 |=0.9885; |f/f 2 |=0.0676; |f/f 3 |=0.2029; |f/f 4 |=0.9900; and |f/f 5 |=1.0196, where PPR is a ratio of a focal length f of the optical image capturing system to a focal length fp of each of the lenses with positive refractive power; and NPR is a ratio of a focal length f of the optical image capturing system to a focal length fn of each of lenses with negative refractive power.
The optical image capturing system of the first preferred embodiment further satisfies InTL+InB=HOS; HOS=4.5 mm; HOI=2.9335 mm; HOS/HOI=1.5340; HOS/f=1.2059; InTL/HOS=0.7597; InS=4.19216 mm; and InS/HOS=0.9316, where InTL is a distance between the object-side surface 112 of the first lens 110 and the image-side surface 154 of the fifth lens 150 ; HOS is a height of the image capturing system, i.e. a distance between the object-side surface 112 of the first lens 110 and the image plane 180 ; InS is a distance between the aperture 100 and the image plane 180 ; HOT is height for image formation of the optical image capturing system, i.e., the maximum image height; and InB is a distance between the image-side surface 154 of the fifth lens 150 and the image plane 180 .
The optical image capturing system of the first preferred embodiment further satisfies ΣTP=2.044092 mm and ΣTP/InTL=0.5979, where ΣTP is a sum of the thicknesses of the lenses 110 - 150 with refractive power. It is helpful to the contrast of image and yield rate of manufacture, and provides a suitable back focal length for installation of other elements.
The optical image capturing system of the first preferred embodiment further satisfies |R 1 /R 2 |=0.3261, where R 1 is a radius of curvature of the object-side surface 112 of the first lens 110 , and R 2 is a radius of curvature of the image-side surface 114 of the first lens 110 . It provides the first lens with a suitable positive refractive power to reduce the increase rate of the spherical aberration.
The optical image capturing system of the first preferred embodiment further satisfies (R 9 −R 10 )/(R 9 +R 10 )=−2.9828, where R 9 is a radius of curvature of the object-side surface 152 of the fifth lens 150 , and R 10 is a radius of curvature of the image-side surface 154 of the fifth lens 150 . It may modify the astigmatic field curvature.
The optical image capturing system of the first preferred embodiment further satisfies ΣPP=f 1 +f 4 =7.5444 mm and f 1 /(f 1 +f 4 )=0.5004, where ΣPP is a sum of the focal lengths fp of each lens with positive refractive power. It is helpful to share the positive refractive power of the first lens 110 to the other positive lenses to avoid the significant aberration caused by the incident rays.
The optical image capturing system of the first preferred embodiment further satisfies ΣNP=f 2 +f 3 +f 5 =−77.2502 mm and f 5 /(f 2 +f 3 +f 5 )=0.0474, where f 2 , f 3 , and f 5 are focal lengths of the second, the third, and the fifth lenses, and ΣNP is a sum of the focal lengths fn of each lens with negative refractive power. It is helpful to share the negative refractive power of the fifth lens 150 to the other negative lenses to avoid the significant aberration caused by the incident rays.
The optical image capturing system of the first preferred embodiment further satisfies IN 12 =0.511659 mm and IN 12 /f=0.1371, where IN 12 is a distance on the optical axis between the first lens 110 and the second lens 120 . It may correct chromatic aberration and improve the performance.
The optical image capturing system of the first preferred embodiment further satisfies TP 1 =0.587988 mm; TP 2 =0.306624 mm; and (TP 1 +IN 12 )/TP 2 =3.5863, where TP 1 is a central thickness of the first lens 110 on the optical axis, and TP 2 is a central thickness of the second lens 120 on the optical axis. It may control the sensitivity of manufacture of the system and improve the performance.
The optical image capturing system of the first preferred embodiment further satisfies TP 4 =0.5129 mm; TP 5 =0.3283 mm; and (TP 5 +IN 45 )/TP 4 =1.5095, where TP 4 is a central thickness of the fourth lens 140 on the optical axis, TP 5 is a central thickness of the fifth lens 150 on the optical axis, and N 45 is a distance on the optical axis between the fourth lens and the fifth lens. It may control the sensitivity of manufacture of the system and improve the performance.
The optical image capturing system of the first preferred embodiment further satisfies TP 3 =0.3083 mm and (TP 2 +TP 3 +TP 4 )/ΣTP=0.5517, where TP 2 , TP 3 , and TP 4 are thicknesses on the optical axis of the second, the third, and the fourth lenses, and ΣTP is a sum of the central thicknesses of all the lenses with refractive power on the optical axis. It may finely modify the aberration of the incident rays and reduce the height of the system.
The optical image capturing system of the first preferred embodiment |InRS 11 |=0.307838 mm; |InRS 12 |=0.0527214 mm; TP 1 =0.587988 mm; and (|InRS 11 |+TP 1 +|InRS 12 |)/TP 1 =1.613208773, where InRS 11 is a displacement in parallel with the optical axis from a point on the object-side surface 112 of the first lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the object-side surface 112 of the first lens; InRS 12 is a displacement in parallel with the optical axis from a point on the image-side surface 114 of the first lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the image-side surface 114 of the first lens; and TP 1 is a central thickness of the first lens 110 on the optical axis. It may control a ratio of the central thickness of the first lens and the effective semi diameter thickness (thickness ratio) to increase the yield rate of manufacture.
The optical image capturing system of the first preferred embodiment |InRS 21 |=0.165699 mm; |InRS 22 |=0.0788662 mm; TP 2 =0.306624 mm; and (|InRS 21 |+TP 2 +|InRS 22 |)/TP 2 =1.797606189, where InRS 21 is a displacement in parallel with the optical axis from a point on the object-side surface 122 of the second lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the object-side surface 122 of the second lens; InRS 22 is a displacement in parallel with the optical axis from a point on the image-side surface 124 of the second lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the image-side surface 124 of the second lens; and TP 2 is a central thickness of the second lens 120 on the optical axis. It may control a ratio of the central thickness of the second lens and the effective semi diameter thickness (thickness ratio) to increase the yield rate of manufacture.
The optical image capturing system of the first preferred embodiment |InRS 31 |=0.383103 mm; |InRS 32 |=−0.411894 mm; TP 3 =0.308255 mm; and (|InRS 31 |+TP 3 +|InRS 32 |)/TP 3 =3.57902386, where InRS 31 is a displacement in parallel with the optical axis from a point on the object-side surface 132 of the third lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the object-side surface 132 of the third lens; InRS 32 is a displacement in parallel with the optical axis from a point on the image-side surface 134 of the third lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the image-side surface 134 of the third lens; and TP 3 is a central thickness of the third lens 130 on the optical axis. It may control a ratio of the central thickness of the third lens and the effective semi diameter thickness (thickness ratio) to increase the yield rate of manufacture.
The optical image capturing system of the first preferred embodiment |InRS 41 |=0.0384 mm; |InRS 42 |=0.263634 mm; TP 4 =0.512923 mm; (|InRS 41 |+TP 4 +|InRS 42 |)/TP 4 =1.588848619, where InRS 41 is a displacement in parallel with the optical axis from a point on the object-side surface 142 of the fourth lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the object-side surface 142 of the fourth lens; InRS 42 is a displacement in parallel with the optical axis from a point on the image-side surface 144 of the fourth lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the image-side surface 144 of the fourth lens; and TP 4 is a central thickness of the fourth lens 140 on the optical axis. It may control a ratio of the central thickness of the fourth lens and the effective semi diameter thickness (thickness ratio) to increase the yield rate of manufacture.
The optical image capturing system of the first preferred embodiment further satisfies |InRS 51 |=0.576871 mm; |InRS 52 |=0.555284 mm; TP 5 =0.328302 mm; and (|InRS 51 |+TP 5 +|InRS 52 |)/TP 5 =4.448516914, where InRS 51 is a displacement in parallel with the optical axis from a point on the object-side surface 152 of the fifth lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the object-side surface 152 of the fifth lens; InRS 52 is a displacement in parallel with the optical axis from a point on the image-side surface 154 of the fifth lens, through which the optical axis passes, to a point at the maximum effective semi diameter of the image-side surface 154 of the fifth lens; and TP 5 is a central thickness of the fifth lens 150 on the optical axis. It may control the positions of the maximum effective semi diameter on both surfaces of the fifth lens, correct the aberration of the spherical field of view, and reduce the size.
The optical image capturing system of the first preferred embodiment satisfies InRSO=1.471911 mm; InRSI=1.3623996 mm; and Σ|InRS|=2.8343106 mm, where InRSO is of a sum of absolute values of the displacements in parallel with the optical axis of each lens with refractive power from the central point on the object-side surface to the point at the maximum effective semi diameter of the object-side surface, i.e. InRSO=|InRS 11 |+|InRS 21 |+|InRS 31 |+|InRS 41 |+|InRS 51 |; InRSI is of a sum of absolute values of the displacements in parallel with the optical axis of each lens with refractive power from the central point on the image-side surface to the point at the maximum effective semi diameter of the image-side surface, i.e. InRSI=|InRS 12 |+|InRS 22 |+|InRS 32 |+|InRS 42 |+|InRS 52 |; and Σ|InRS| is of an sum of absolute values of the displacements in parallel with the optical axis of each lens with refractive power from the central point to the point at the maximum effective semi diameter, i.e. Σ|InRS|=InRSO+InRSI. It may efficiently increase the capability of modifying the off-axis view field aberration of the system.
The optical image capturing system of the first preferred embodiment satisfies Σ|InRS|/InTL=0.856804897 and Σ|InRS|/HOS=0.632658616. It may reduce the total height of the system as well as efficiently increase the capability of modifying the off-axis view field aberration of the system.
The optical image capturing system of the first preferred embodiment satisfies |InRS 41 |+|InRS 42 |+|InRS 51 |+|InRS 52 |=1.434189 mm; |InRS 41 |+|InRS 42 |+|InRS 51 |+|InRS 52 |)/InTL=0.433551693; and (|InRS 41 |+|InRS 42 |+|InRS 51 |+|InRS 52 |)/HOS=0.320131473. It may increase yield rate of the lenses of the first and the second closest to the image side as well as efficiently increase the capability of modifying the off-axis view field aberration of the system.
The optical image capturing system of the first preferred embodiment satisfies HVT 41 =1.28509 mm and HVT 42 =0 mm, where HVT 41 a distance perpendicular to the optical axis between the inflection point on the object-side surface of the fourth lens and the optical axis; and HVT 42 a distance perpendicular to the optical axis between the inflection point on the image-side surface of the fourth lens and the optical axis. It may efficiently modify the aberration of the peripheral view field of the system.
The optical image capturing system of the first preferred embodiment satisfies HVT 51 =0 mm; HVT 52 =1.06804 mm; and HVT 51 /HVT 52 =0, where HVT 51 a distance perpendicular to the optical axis between the inflection point on the object-side surface of the fifth lens and the optical axis; and HVT 52 a distance perpendicular to the optical axis between the inflection point on the image-side surface of the fifth lens and the optical axis. It may efficiently modify the aberration of the off-axis view field of the system.
The optical image capturing system of the first preferred embodiment satisfies HVT 52 /HOI=0.364083859. It may efficiently modify the aberration of the off-axis view field of the system.
The optical image capturing system of the first preferred embodiment satisfies HVT 52 /HOS=0.237342222. It may efficiently modify the aberration of the peripheral view field of the system.
In the first embodiment, the first lens 110 and the fifth lens 150 are negative lenses. The optical image capturing system of the first preferred embodiment further satisfies NA 5 /NA 2 =2.5441, where NA 2 is an Abbe number of the second lens 120 , and NA 5 is an Abbe number of the fifth lens 150 . It may correct the aberration of the system.
The optical image capturing system of the first preferred embodiment further satisfies |TDT|=0.6343% and |ODT|=2.5001%, where TDT is TV distortion; and ODT is optical distortion.
The parameters of the lenses of the first embodiment are listed in Table 1 and Table 2.
TABLE 1
f = 3.73172 mm; f/HEP = 2.05; HAF = 37.5 deg; tan(HAF) = 0.7673
Radius of
Thickness
Refractive
Abbe
Focal length
Surface
curvature (mm)
(mm)
Material
index
number
(mm)
0
Object
plane
infinity
1
Aperture
plane
−0.30784
2
1 st lens
1.48285
0.587988
plastic
1.5441
56.1
3.77514
3
4.54742
0.511659
4
2 nd lens
−9.33807
0.306624
plastic
1.6425
22.465
−55.2008
5
−12.8028
0.366935
6
3 rd lens
−1.02094
0.308255
plastic
1.6425
22.465
−18.3893
7
−1.2492
0.05
8
4 th lens
2.18916
0.512923
plastic
1.5441
56.1
3.7693
9
−31.3936
0.44596
10
5 th lens
−2.86353
0.328302
plastic
1.514
57.1538
−3.6601
11
5.75188
0.3
12
Filter
plane
0.2
1.517
64.2
13
plane
0.58424
14
Image
plane
−0.00289
plane
Reference wavelength: 555 nm
TABLE 2
Coefficients of the aspheric surfaces
Surface
2
3
4
5
6
k
−1.83479
−20.595808
16.674705
11.425456
−4.642191
A4
6.89867E−02
2.25678E−02
−1.11828E−01
−4.19899E−02
−7.09315E−02
A6
2.35740E−02
−6.17850E−02
−6.62880E−02
−1.88072E−02
9.65840E−02
A8
−4.26369E−02
5.82944E−02
−3.35190E−02
−6.98321E−02
−7.32044E−03
A10
5.63746E−03
−2.73938E−02
−7.28886E−02
−1.13079E−02
−8.96740E−02
A12
7.46740E−02
−2.45759E−01
4.05955E−02
6.79127E−02
−3.70146E−02
A14
−6.93116E−02
3.43401E−01
1.60451E−01
2.83769E−02
5.00641E−02
A16
−2.04867E−02
−1.28084E−01
1.24448E−01
−2.45035E−02
7.50413E−02
A18
1.99910E−02
−2.32031E−02
−1.94856E−01
2.90241E−02
−5.10392E−02
A20
Surface
7
8
9
10
11
k
−1.197201
−20.458388
−50
−2.907359
−50
A4
3.64395E−02
−1.75641E−02
−7.82211E−04
−1.58711E−03
−2.46339E−02
A6
2.22356E−02
−2.87240E−03
−2.47110E−04
−3.46504E−03
6.61804E−04
A8
7.09828E−03
−2.56360E−04
−3.78130E−04
4.52459E−03
1.54143E−04
A10
5.05740E−03
7.39189E−05
−1.22232E−04
1.05841E−04
−2.83264E−05
A12
−4.51124E−04
−5.53116E−08
−1.50294E−05
−5.57252E−04
−5.78839E−06
A14
−1.84003E−03
8.16043E−06
−5.41743E−07
4.41714E−05
−2.91861E−07
A16
−1.28118E−03
2.10395E−06
2.98820E−07
1.80752E−05
8.25778E−08
A18
4.09004E−04
−1.21664E−06
2.73321E−07
−2.27031E−06
−9.87595E−09
A20
The detail parameters of the first preferred embodiment are listed in Table 1, in which the unit of radius of curvature, thickness, and focal length are millimeter, and surface 0-14 indicates the surfaces of all elements in the system in sequence from the object side to the image side. Table 2 is the list of coefficients of the aspheric surfaces, in which A1-A20 indicate the coefficients of aspheric surfaces from the first order to the twentieth order of each aspheric surface. The following embodiments have the similar diagrams and tables, which are the same as those of the first embodiment, so we do not describe it again.
Second Embodiment
As shown in FIG. 2A and FIG. 2B , an optical image capturing system of the second preferred embodiment of the present invention includes, along an optical axis from an object side to an image side, an aperture 200 , a first lens 210 , a second lens 220 , a third lens 230 , a fourth lens 240 , a fifth lens 250 , an infrared rays filter 270 , an image plane 280 , and an image sensor 290 .
The first lens 210 has positive refractive power, and is made of plastic. An object-side surface 212 thereof, which faces the object side, is a convex aspheric surface, and an image-side surface 214 thereof, which faces the image side, is a concave aspheric surface. The image-side surface 214 has an inflection point.
The second lens 220 has negative refractive power, and is made of plastic. An object-side surface 222 , which faces the object side, thereof has a convex aspheric surface, and an image-side surface 224 , which faces the image side, thereof is a concave aspheric surface. The object-side surface 222 has an inflection point, and the image-side surface 224 has two inflection points.
The third lens 230 has positive refractive power, and is made of plastic. An object-side surface 232 , which faces the object side, is a concave aspheric surface, and an image-side surface 234 , which faces the image side, is a convex aspheric surface, and the object-side surface 232 and the image-side surface 234 each has an inflection point.
The fourth lens 240 has positive refractive power, and is made of plastic. An object-side surface 242 , which faces the object side, thereof is a concave aspheric surface, and an image-side surface 244 , which faces the image side, thereof is a convex aspheric surface, and each of them has an inflection point.
The fifth lens 250 has negative refractive power, and is made of plastic. An object-side surface 252 , which faces the object side, is a concave aspheric surface, and an image-side surface 254 , which faces the image side, is a concave aspheric surface. The image-side surface 254 has an inflection point.
The infrared rays filter 270 is made of glass, and between the fifth lens 250 and the image plane 280 . The infrared rays filter 270 gives no contribution to the focal length of the system.
The optical image capturing system of the second preferred embodiment has the following parameters, which are |f 2 |+|f 3 |+|f 4 |=37.5373 mm, |f 1 |+|f 5 |=7.9194 mm, and |f 2 |+|f 3 |+|f 4 |>|f 1 |+|f 5 |, where f 1 is a focal length of the first lens 210 ; f 2 is a focal length of the second lens 220 ; f 3 is a focal length of the third lens 230 ; f 4 is a focal length of the fourth lens 240 ; and f 5 is a focal length of the fifth lens 250 .
The optical image capturing system of the second preferred embodiment further satisfies TP 4 =0.7048 mm and TP 5 =0.3912 mm, where TP 4 is a thickness of the fourth lens on the optical axis, and TP 5 is a thickness of the fifth lens on the optical axis.
In the second embodiment, the first, the third, and the fourth lenses 210 , 230 , and 240 are positive lenses, and their focal lengths are f 1 , f 3 , and f 4 . ΣPP is a sum of the focal lengths of each positive lens. It is helpful to share the positive refractive power of the first lens 210 to the other positive lenses to avoid the significant aberration caused by the incident rays.
In the second preferred embodiment, the second and the fifth lenses 220 and 250 are negative lenses, and their focal lengths are f 2 and f 5 . ΣNP is a sum of the focal lengths of each negative lens. It is helpful to share the negative refractive power of the fifth lens 250 to the other negative lenses to avoid the significant aberration caused by the incident rays.
The parameters of the lenses of the second embodiment are listed in Table 3 and Table 4.
TABLE 3
f = 3.04474 mm; f/HEP = 1.4; HAF = 50.0002 deg; tan(HAF) = 1.1918
Radius of
Thickness
Refractive
Abbe
Focal length
Surface
curvature (mm)
(mm)
Material
index
number
(mm)
0
Object
plane
infinity
1
Aperture
infinity
−0.31441
2
1 st lens
2.20673
0.411318
plastic
1.565
58
6.28889
3
5.4028
0.510799
4
2 nd lens
9.51235
0.2
plastic
1.65
21.4
−30.5763
5
6.39691
0.06878
6
3 rd lens
−29.9399
1.133545
plastic
1.565
58
4.63066
7
−2.44608
0.130206
8
4 th lens
−5.73148
0.70476
plastic
1.607
26.6
2.33036
9
−1.19388
0.449239
10
5 th lens
−2.01485
0.391231
plastic
1.65
21.4
−1.63051
11
2.45082
0.4
12
Filter
infinity
0.2
1.517
64.2
13
infinity
0.349594
14
Image
infinity
plane
Reference wavelength: 555 nm; position of blocking light: blocking at the fourth surface with effective semi diameter of 1.05 mm.
TABLE 4
Coefficients of the aspheric surfaces
Surface
2
3
4
5
6
k
0.286533
−8.244129
−35.082575
−50
50
A4
3.84219E−03
3.02641E−02
−1.51099E−01
−5.74219E−02
1.23903E−02
A6
5.55804E−02
−5.04066E−02
−2.11069E−02
−1.30714E−01
−3.55675E−02
A8
−1.48618E−01
9.75086E−02
−5.13379E−02
1.97663E−01
3.82511E−02
A10
1.93241E−01
−1.15283E−01
1.14370E−01
−1.53379E−01
−1.74251E−02
A12
−1.07560E−01
8.13581E−02
−1.36206E−01
5.58656E−02
4.53820E−03
A14
1.91982E−02
−3.26764E−02
3.81604E−02
−6.15078E−03
−5.11068E−04
Surface
7
8
9
10
11
k
0.767661
6.669586
−3.146326
0.091085
−10.235913
A4
4.98629E−03
−1.47899E−02
5.58711E−03
1.36758E−01
3.53284E−03
A6
−3.41408E−02
1.26542E−02
−2.32654E−02
−7.53831E−02
−1.37235E−02
A8
2.60941E−02
−9.49276E−03
2.02171E−02
5.80670E−03
4.96294E−03
A10
−1.13517E−02
5.07336E−03
−7.33256E−03
1.03780E−02
−8.55116E−04
A12
2.30791E−03
−1.06311E−03
1.33148E−03
−3.97156E−03
7.06088E−05
A14
3.89425E−05
8.08345E−05
−9.28261E−05
4.46112E−04
−2.29052E−06
An equation of the aspheric surfaces of the second embodiment is the same as that of the first embodiment, and the definitions are the same as well.
The exact parameters of the second embodiment based on Table 3 and Table 4 are listed in the following table:
Second embodiment (Reference wavelength: 555 nm)
InRS11
InRS12
InRS21
InRS22
InRS31
InRS32
0.31441
0.10243
−0.21762
−0.13002
0.05135
−0.70439
InRS41
InRS42
InRS51
InRS52
HVT51
HVT52
−0.26322
−0.73306
−1.13201
−0.34899
0.00000
1.90704
|ODT|
|TDT|
InRSO
InRSI
Σ|InRS|
2.25805
1.37178
1.97860
2.01889
3.99749
Σ|InRS|/
Σ|InRS|/
(|InRS32| + |InRS41|)/
(|InRS42| + |InRS51|)/
InTL
HOS
IN34
IN45
0.99940
0.80766
7.4314
4.1516
(|InRS41| + |InRS42| + |InRS51| +
(|InRS41| + |InRS42| + |InRS51| +
|InRS52|)/InTL
|InRS52|)/HOS
0.61934
0.50051
|f/f1|
|f/f2|
|f/f3|
|f/f4|
|f/f5|
|f1/f2|
0.48415
0.09958
0.65752
1.30655
1.86735
0.20568
Σ PPR/|Σ
Σ PPR
Σ NPR
NPR|
Σ PP
Σ NP
IN12/f
2.44822
1.96693
1.24469
13.24991
−32.20681
0.47464
HVT52/
HVT52/
|InRS51|/
|InRS52|/
f1/Σ PP
f5 Σ NP
HOI
HOS
TP5
TP5
0.05063
0.16776
0.5099
0.3853
2.8935
0.8920
InTL
HOS
HOS/HOI
InS/HOS
InTL/HOS
Σ TP/InTL
4.94947
3.99988
1.32339
0.93648
0.80814
0.71023
HVT41
HVT42
1.77754
0
The exact parameters of the inflection points of the second embodiment based on Table 3 and Table 4 are listed in the following table:
Second embodiment (Reference wavelength: 555 nm)
HIF121
0.88751
HIF121/
0.23730
SGI121
0.07965
|SGI121|/(|SGI121| +
0.16223
HOI
TP1)
HIF211
0.23445
HIF211/
0.06269
SGI211
0.00241
|SGI211|/(|SGI211| +
0.00000
HOI
TP2)
HIF221
0.35152
HIF221/
0.09399
SGI221
0.00824
|SGI221|/(|SGI221| +
0.28482
HOI
TP2)
HIF222
1.18543
HIF222/
0.31696
SGI222
−0.09891
|SGI222|/(|SGI222| +
0.00000
HOI
TP2)
HIF311
0.84976
HIF311/
0.22721
SGI311
−0.01155
|SGI311|/(|SGI311| +
0.01008
HOI
TP3)
HIF321
1.41374
HIF321/
0.37801
SGI321
−0.54447
|SGI321|/(|SGI321| +
0.32448
HOI
TP3)
HIF411
1.31111
HIF411/
0.35056
SGI411
−0.17910
|SGI411|/(|SGI411| +
0.20264
HOI
TP4)
HIF421
1.21613
HIF421/
0.32517
SGI421
−0.44870
|SGI421|/(|SGI421| +
0.38900
HOI
TP4)
HIF521
0.90504
HIF521/
0.24199
SGI521
0.13029
|SGI521|/(|SGI521| +
0.24982
HOI
TP5)
Third Embodiment
As shown in FIG. 3A and FIG. 3B , an optical image capturing system of the third preferred embodiment of the present invention includes, along an optical axis from an object side to an image side, an aperture 300 , a first lens 310 , a second lens 320 , a third lens 330 , a fourth lens 340 , a fifth lens 350 , an infrared rays filter 370 , an image plane 380 , and an image sensor 390 .
The first lens 310 has positive refractive power, and is made of plastic. An object-side surface 312 thereof, which faces the object side, is a convex aspheric surface, and an image-side surface 314 thereof, which faces the image side, is a concave aspheric surface. The image-side surface 314 has an inflection point.
The second lens 320 has negative refractive power, and is made of plastic. An object-side surface 322 thereof, which faces the object side, is a convex aspheric surface, and an image-side surface 324 thereof, which faces the image side, is a concave aspheric surface, and both the object-side surface 322 and the image-side surface 324 each has an inflection point.
The third lens 330 has positive refractive power, and is made of plastic. Both an object-side surface 332 , which faces the object side, and an image-side surface 334 thereof, which faces the image side, are convex aspheric surfaces, and the object-side surface 332 has two inflection points, and the image-side surface 334 has an inflection point.
The fourth lens 340 has a positive refractive power, and is made of plastic. An object-side surface 342 , which faces the object side, is a convex aspheric surface, and an image-side surface 344 , which faces the image side, is a convex aspheric surface. The object-side surface 342 has two inflection points, and the image-side surface 344 has an inflection point.
The fifth lens 350 has negative refractive power, and is made of plastic. An object-side surface 352 , which faces the object side, is a concave aspheric surface, and an image-side surface 354 , which faces the image side, is a concave aspheric surface. The image-side surface 354 has an inflection point.
The infrared rays filter 370 is made of glass, and between the fifth lens 350 and the image plane 380 . The infrared rays filter 370 gives no contribution to the focal length of the system.
The parameters of the lenses of the third preferred embodiment are |f 2 |+|f 3 |+|f 4 |=32.4226 mm; |f 1 |+|f 5 |=8.1201 mm; and |f 2 |+|f 3 |+|f 4 |>|f 1 |+|f 5 |, where f 1 is a focal length of the first lens 310 ; f 2 is a focal length of the second lens 320 ; f 3 is a focal length of the third lens 330 ; and f 4 is a focal length of the fourth lens 340 ; and f 5 is a focal length of the fifth lens 350 .
The optical image capturing system of the third preferred embodiment further satisfies TP 4 =1.0277 mm and TP 5 =0.3571 mm, where TP 4 is a thickness of the fourth lens 340 on the optical axis, and TP 5 is a thickness of the fifth lens 350 on the optical axis.
In the third embodiment, the first, the third, and the fourth lenses 310 , 330 , and 340 are positive lenses, and their focal lengths are f 1 , f 3 , and f 4 . ΣPP is a sum of the focal lengths of each positive lens. It is helpful to share the positive refractive power of the first lens 310 to the other positive lenses to avoid the significant aberration caused by the incident rays.
In the third embodiment, the second and the fifth lenses 320 and 350 are negative lenses, and their focal lengths are f 2 and f 5 . ΣNP is a sum of the focal lengths of each negative lens. It is helpful to share the negative refractive power of the fifth lens 350 to the other negative lenses.
The parameters of the lenses of the third embodiment are listed in Table 5 and Table 6.
TABLE 5
f = 3.05885 mm; f/HEP = 1.6; HAF = 50.0004 deg; tan(HAF) = 1.1918
Radius of
Thickness
Refractive
Abbe
Focal length
Surface
curvature (mm)
(mm)
Material
index
number
(mm)
0
Object
plane
infinity
1
Aperture
infinity
−0.20702
2
1 st lens
2.32343
0.353041
plastic
1.565
58
6.58097
3
5.82279
0.457376
4
2 nd lens
7.94316
0.2
plastic
1.65
21.4
−19.4179
5
4.84204
0.076567
6
3 rd lens
15.63605
0.834209
plastic
1.565
58
11.2433
7
−10.5486
0.332193
8
4 th lens
5.91378
1.027713
plastic
1.607
26.6
1.76135
9
−1.22915
0.339447
10
5 th lens
−2.41538
0.357068
plastic
1.65
21.4
−1.53908
11
1.83365
0.5
12
Filter
infinity
0.2
1.517
64.2
13
infinity
0.269115
14
Image
infinity
plane
Reference wavelength: 555 nm.
TABLE 6
Coefficients of the aspheric surfaces
Surface
2
3
4
5
6
k
1.115215
11.130271
−4.865377
−35.432749
−50
A4
−1.22823E−02
6.98730E−03
−8.42639E−02
8.33111E−03
−1.04830E−02
A6
4.09036E−02
−7.23714E−02
−5.67365E−02
−1.54384E−01
−3.80907E−02
A8
−1.26323E−01
1.26898E−01
−3.15710E−02
1.88117E−01
4.40527E−02
A10
1.82929E−01
−1.41596E−01
1.04374E−01
−1.44884E−01
−1.76411E−02
A12
−1.37740E−01
6.49432E−02
−1.24170E−01
6.03040E−02
3.66285E−03
A14
3.65585E−02
−1.71854E−02
3.18231E−02
−1.02849E−02
−2.75988E−04
Surface
7
8
9
10
11
k
29.732304
−43.181612
−4.099814
0.602956
−11.784731
A4
−8.34945E−02
−5.06881E−02
−3.12119E−03
7.84581E−02
7.00755E−03
A6
−1.68832E−02
1.05343E−02
−2.49976E−02
−5.49218E−02
−1.58596E−02
A8
2.41127E−02
−1.04770E−02
1.96079E−02
3.36415E−03
5.17853E−03
A10
−1.34748E−02
4.88607E−03
−7.49422E−03
9.94439E−03
−8.54091E−04
A12
2.24863E−03
−1.04418E−03
1.32973E−03
−3.84911E−03
7.03304E−05
A14
5.03578E−04
1.11042E−04
−7.55412E−05
4.42762E−04
−2.34893E−06
An equation of the aspheric surfaces of the third embodiment is the same as that of the first embodiment, and the definitions are the same as well.
The exact parameters of the third embodiment based on Table 5 and Table 6 are listed in the following table:
Third embodiment (Reference wavelength: 555 nm)
InRS11
InRS12
InRS21
InRS22
InRS31
InRS32
0.20702
0.06238
−0.19270
−0.06988
0.08479
−0.47135
InRS41
InRS42
InRS51
InRS52
HVT51
HVT52
−0.20043
−0.88560
−1.17465
−0.45992
0.00000
1.74263
|ODT|
|TDT|
InRSO
InRSI
Σ|InRS|
2.07460
1.21381
1.85958
1.94913
3.80871
Σ|InRS|/
Σ|InRS|/
(|InRS32| + |InRS41|)/
(|InRS42| + |InRS51|)/
InTL
HOS
IN34
IN45
0.95754
0.76995
2.0222
6.0694
(|InRS41| + |InRS42| + |InRS51| +
(|InRS41| + |InRS42| + |InRS51| +
|InRS52|)/InTL
|InRS52|)/HOS
0.68398
0.54998
|f/f1|
|f/f2|
|f/f3|
|f/f4|
|f/f5|
|f1/f2|
0.46480
0.15753
0.27206
1.73665
1.98745
0.33891
Σ PPR/|Σ
Σ PPR
Σ NPR
NPR|
Σ PP
Σ NP
f1/Σ PP
2.47351
2.14498
1.15316
19.58562
−20.95698
0.33601
HVT52/
HVT52/
|InRS51|/
|InRS52|/
f5 Σ NP
IN12/f
HOI
HOS
TP5
TP5
0.07344
0.14953
0.4659
0.3523
3.2897
1.2881
InTL
HOS
HOS/HOI
InS/HOS
InTL/HOS
Σ TP/InTL
4.94673
3.97761
1.32266
0.95815
0.80409
0.69691
HVT41
HVT42
0.822206
0
The exact parameters of the inflection points of the third embodiment based on Table 5 and Table 6 are listed in the following table:
Third embodiment (Reference wavelength: 555 nm)
HIF121
0.73520
HIF121/
0.19658
SGI121
0.04521
|SGI121|/(|SGI121| +
0.11351
HOI
TP1)
HIF211
0.32257
HIF211/
0.08625
SGI211
0.00556
|SGI211|/(|SGI211| +
0.02705
HOI
TP2)
HIF221
0.48706
HIF221/
0.13023
SGI221
0.02157
|SGI221|/(|SGI221| +
0.09737
HOI
TP2)
HIF311
0.46827
HIF311/
0.12521
SGI311
0.00612
|SGI311|/(|SGI311| +
0.00729
HOI
TP3)
HIF312
0.92223
HIF312/
0.24659
SGI312
0.01161
|SGI312|/(|SGI312| +
0.01372
HOI
TP3)
HIF321
1.33361
HIF321/
0.35658
SGI321
−0.35650
|SGI321|/(|SGI321| +
0.29940
HOI
TP3)
HIF411
0.46150
HIF411/
0.12339
SGI411
0.01476
|SGI411|/(|SGI411| +
0.01416
HOI
TP4)
HIF412
1.58641
HIF412/
0.42417
SGI412
−0.13299
|SGI412|/(|SGI412| +
0.11458
HOI
TP4)
HIF421
1.64121
HIF421/
0.43883
SGI421
−0.72795
|SGI421|/(|SGI421| +
0.41463
HOI
TP4)
HIF521
0.83907
HIF521/
0.22435
SGI521
0.13595
|SGI521|/(|SGI521| +
0.27575
HOI
TP5)
Fourth Embodiment
As shown in FIG. 4A and FIG. 4B , an optical image capturing system of the fourth preferred embodiment of the present invention includes, along an optical axis from an object side to an image side, an aperture 400 , a first lens 410 , a second lens 420 , a third lens 430 , a fourth lens 440 , a fifth lens 450 , an infrared rays filter 470 , an image plane 480 , and an image sensor 490 .
The first lens 410 has positive refractive power, and is made of plastic. An object-side surface 412 thereof, which faces the object side, is a convex aspheric surface, and an image-side surface 414 thereof, which faces the image side, is a concave aspheric surface. The image-side surface 414 has an inflection point.
The second lens 420 has negative refractive power, and is made of plastic. An object-side surface 422 thereof, which faces the object side, is a convex aspheric surface, and an image-side surface 424 thereof, which faces the image side, is a concave aspheric surface. The object-side surface 422 has an inflection point, and the image-side surface 424 has two inflection points.
The third lens 430 has positive refractive power, and is made of plastic. Both an object-side surface 432 thereof, which faces the object side, and an image-side surface 434 thereof, which faces the image side, are convex aspheric surfaces. The object-side surface 432 has two inflection points, and the image-side surface 434 has an inflection point.
The fourth lens 440 has positive refractive power, and is made of plastic. An object-side surface 442 , which faces the object side, is a convex aspheric surface, and an image-side surface 444 , which faces the image side, is a convex aspheric surface. The object-side surface 442 and the image-side surface 444 each has an inflection point.
The fifth lens 450 has negative refractive power, and is made of plastic. An object-side surface 452 thereof, which faces the object side, is a concave aspheric surface, and an image-side surface 454 thereof, which faces the image side, is a concave aspheric surface. The object-side surface 452 and the image-side surface 454 each has an inflection point.
The infrared rays filter 470 is made of glass, and between the fifth lens 450 and the image plane 480 . The infrared rays filter 470 gives no contribution to the focal length of the system.
The optical image capturing system of the fourth preferred embodiment has the following parameters, which are |f 2 |+f 3 |+|f 4 |=26.7777 mm; |f 1 |+|f 5 |=7.5798 mm; and |f 2 |+|f 3 |+|f 4 |>|f 1 |+|f 5 |, where f 1 is a focal length of the first lens 410 ; f 2 is a focal length of the second lens 420 ; f 3 is a focal length of the third lens 430 ; f 4 is a focal length of the fourth lens 440 ; and f 5 is a focal length of the fifth lens 450 .
The optical image capturing system of the fourth preferred embodiment further satisfies TP 4 =0.6641 mm and TP 5 =0.3846 mm, where TP 4 is a thickness of the fourth lens 340 on the optical axis, and TP 5 is a thickness of the fifth lens 350 on the optical axis.
In the fourth embodiment, the first, the third, and the fourth lenses 410 , 430 , and 440 are positive lenses, and their focal lengths are f 1 , f 3 , and f 4 . ΣPP is a sum of the focal lengths of each positive lens. It is helpful to share the positive refractive power of the first lens 410 to the other positive lenses to avoid the significant aberration caused by the incident rays.
In the fourth embodiment, the second and the fifth lenses 420 and 450 are negative lenses, and their focal lengths are f 2 and f 5 . ΣNP is a sum of the focal lengths of each negative lens. It is helpful to share the negative refractive power of the fifth lens 450 to the other negative lenses.
The parameters of the lenses of the fourth embodiment are listed in Table 7 and Table 8.
TABLE 7
f = 3.10964 mm; f/HEP = 1.8; HAF = 50.0001 deg; tan(HAF) = 1.1918
Radius of
Thickness
Refractive
Abbe
Focal length
Surface
curvature (mm)
(mm)
Material
index
number
(mm)
0
Object
plane
infinity
1
Aperture
infinity
−0.22952
2
1 st lens
1.85543
0.323351
plastic
1.565
58
5.76521
3
4.02259
0.451954
4
2 nd lens
13.22816
0.2
plastic
1.65
21.4
−15.7807
5
5.76987
0.063866
6
3 rd lens
14.30372
0.813297
plastic
1.565
58
8.81139
7
−7.51537
0.440432
8
4 th lens
3.9112
0.664104
plastic
1.583
30.2
2.18556
9
−1.78697
0.423446
10
5 th lens
−1.69555
0.384614
plastic
1.632
23.4
−1.81457
11
3.94917
0.3
12
Filter
infinity
0.2
1.517
64.2
13
infinity
0.329249
14
Image
infinity
plane
Reference wavelength: 555 nm.
TABLE 8
Coefficients of the aspheric surfaces
Surface
2
3
4
5
6
k
0.81056
6.920254
−50
22.219487
50
A4
−8.08919E−03
1.66907E−02
−9.41408E−02
−6.59309E−02
−2.45875E−02
A6
6.16441E−02
−7.37384E−02
−9.33631E−02
−1.18278E−01
−3.63650E−02
A8
−1.34347E−01
1.55040E−01
6.32463E−02
1.62882E−01
3.45634E−02
A10
1.66548E−01
−1.63622E−01
4.55174E−04
−1.23873E−01
2.49263E−03
A12
−1.00744E−01
5.75888E−02
−9.90199E−02
5.03186E−02
−9.62709E−03
A14
2.28465E−02
−1.16382E−02
2.19684E−02
−8.64796E−03
2.47321E−03
Surface
7
8
9
10
11
k
13.90358
2.080982
−1.563385
−0.358726
−23.55212
A4
−7.68123E−02
−7.53626E−02
2.96645E−02
1.23832E−02
2.55146E−03
A6
−1.25192E−02
2.26118E−02
−2.49354E−02
−1.92842E−03
−1.34850E−02
A8
1.82598E−02
−1.59430E−02
1.78544E−02
−1.12204E−02
4.86038E−03
A10
−1.46102E−02
4.95408E−03
−7.93350E−03
1.20226E−02
−8.55387E−04
A12
3.06895E−03
−1.65361E−03
1.30293E−03
−3.72413E−03
7.21051E−05
A14
3.15123E−04
1.12446E−04
−2.73636E−05
3.87876E−04
−2.40558E−06
An equation of the aspheric surfaces of the fourth embodiment is the same as that of the first embodiment, and the definitions are the same as well.
The exact parameters of the fourth embodiment based on Table 7 and Table 8 are listed in the following table:
Fourth embodiment (Reference wavelength: 555 nm)
InRS11
InRS12
InRS21
InRS22
InRS31
InRS32
0.22952
0.10617
−0.12818
−0.00459
0.00924
−0.53297
InRS41
InRS42
InRS51
InRS52
HVT51
HVT52
−0.38714
−0.82986
−1.15388
−0.64707
0.00000
1.52391
|ODT|
|TDT|
InRSO
InRSI
Σ|InRS|
1.57549
1.10615
1.90796
2.12066
4.02862
Σ|InRS|/
Σ|InRS|/
(|InRS32| + |InRS41|)/
(|InRS42| + |InRS51|)/
InTL
HOS
IN34
IN45
1.07000
0.87687
2.0891
4.6848
(|InRS41| + |InRS42| + |InRS51| +
(|InRS41| + |InRS42| + |InRS51| +
|InRS52|)/InTL
|InRS52|)/HOS
0.80157
0.65689
|f/f1|
|f/f2|
|f/f3|
|f/f4|
|f/f5|
|f1/f2|
0.53938
0.19705
0.35291
1.42281
1.71371
0.36533
Σ PPR/|Σ
Σ PPR
Σ NPR
NPR|
Σ PP
Σ NP
f1/Σ PP
2.31510
1.91076
1.21161
16.76216
−17.59527
0.34394
HVT52/
HVT52/
|InRS51|/
|InRS52|/
f5 Σ NP
IN12/f
HOI
HOS
TP5
TP5
0.10313
0.14534
0.4075
0.3317
3.0001
1.6824
InTL
HOS
HOS/HOI
InS/HOS
InTL/HOS
Σ TP/InTL
4.59431
3.76506
1.22843
0.95004
0.81950
0.63355
HVT41
HVT42
1.04217
0
The exact parameters of the inflection points of the fourth embodiment based on Table 7 and Table 8 are listed in the following table:
Fourth embodiment (Reference wavelength: 555 nm)
HIF121
0.83523
HIF121/
0.22332
SGI121
0.09421
|SGI121|/(|SGI121| +
0.22562
HOI
TP1)
HIF211
0.24014
HIF211/
0.06421
SGI211
0.00184
|SGI211|/(|SGI211| +
0.00912
HOI
TP2)
HIF221
0.42148
HIF221/
0.11270
SGI221
0.01330
|SGI221|/(|SGI221| +
0.06236
HOI
TP2)
HIF222
1.03865
HIF222/
0.27771
SGI222
0.00385
|SGI222|/(|SGI222| +
0.01887
HOI
TP2)
HIF311
0.41856
HIF311/
0.11192
SGI311
0.00527
|SGI311|/(|SGI311| +
0.00644
HOI
TP3)
HIF312
0.94855
HIF312/
0.25362
SGI312
0.00725
|SGI312|/(|SGI312| +
0.00883
HOI
TP3)
HIF322
1.41359
HIF322/
0.37797
SGI322
−0.50303
|SGI322|/(|SGI322| +
0.38215
HOI
TP3)
HIF411
0.61785
HIF411/
0.16520
SGI411
0.03975
|SGI411|/(|SGI411| +
0.05647
HOI
TP4)
HIF421
1.66767
HIF421/
0.44590
SGI421
−0.69186
|SGI421|/(|SGI421| +
0.51024
HOI
TP4)
HIF511
1.81375
HIF511/
0.48496
SGI511
−0.99942
|SGI511|/(|SGI511| +
0.72211
HOI
TP5)
HIF521
0.81503
HIF521/
0.21792
SGI521
0.06809
|SGI521|/(|SGI521| +
0.15042
HOI
TP5)
Fifth Embodiment
As shown in FIG. 5A and FIG. 5B , an optical image capturing system of the fifth preferred embodiment of the present invention includes, along an optical axis from an object side to an image side, an aperture 500 , a first lens 510 , a second lens 520 , a third lens 530 , a fourth lens 540 , a fifth lens 550 , an infrared rays filter 570 , an image plane 580 , and an image sensor 590 .
The first lens 510 has positive refractive power, and is made of plastic. An object-side surface 512 thereof, which faces the object side, is a convex aspheric surface, and an image-side surface 514 thereof, which faces the image side, is a concave aspheric surface. The image-side surface 514 has an inflection point.
The second lens 520 has negative refractive power, and is made of plastic. An object-side surface 522 thereof, which faces the object side, is a concave aspheric surface, and an image-side surface 524 thereof, which faces the image side, is a convex aspheric surface.
The third lens 530 has positive refractive power, and is made of plastic. An object-side surface 532 thereof, which faces the object side, is a convex aspheric surface, and an image-side surface 534 thereof, which faces the image side, is a concave aspheric surface. The object-side surface 532 has an inflection point, and the image-side surface 534 has two inflection points.
The fourth lens 540 has a positive refractive power, and is made of plastic. An object-side surface 542 , which faces the object side, is a concave aspheric surface, and an image-side surface 544 , which faces the image side, is a convex aspheric surface. The object-side surface 542 and the image-side surface 544 each has an inflection point.
The fifth lens 550 has negative refractive power, and is made of plastic. An object-side surface 552 thereof, which faces the object side, is a convex aspheric surface, and an image-side surface 554 thereof, which faces the image side, is a concave aspheric surface. The object-side surface 552 and the image-side surface 554 each has an inflection point.
The infrared rays filter 570 is made of glass, and between the fifth lens 550 and the image plane 580 . The infrared rays filter 570 gives no contribution to the focal length of the system.
The parameters of the lenses of the fifth preferred embodiment are |f 2 |+f 3 |+|f 4 |=112.7630 mm; |f 1 |+|f 5 |=7.5905 mm; and |f 2 |+|f 3 |+|f 4 |>|f 1 |+|f 5 |, where f 1 is a focal length of the first lens 510 ; f 2 is a focal length of the second lens 520 ; f 3 is a focal length of the third lens 530 ; and f 4 is a focal length of the fourth lens 540 ; and f 5 is a focal length of the fifth lens 550 .
The optical image capturing system of the fifth preferred embodiment further satisfies TP 4 =1.4369 mm and TP 5 =0.7193 mm, where TP 4 is a thickness of the fourth lens 540 on the optical axis, and TP 5 is a thickness of the fifth lens 550 on the optical axis.
In the fifth preferred embodiment, the first, the third, and the fourth lenses 510 , 530 , and 540 are positive lenses, and their focal lengths are f 1 , f 3 , and f 4 . ΣPP is a sum of the focal lengths of each positive lens. It is helpful to share the positive refractive power of the first lens 510 to the other positive lenses to avoid the significant aberration caused by the incident rays.
In the fifth preferred embodiment, the second and the fifth lenses 520 and 550 are negative lenses, and their focal lengths are f 2 and f 5 . ΣNP is a sum of the focal lengths of each negative lens. It is helpful to share the negative refractive power of the fifth lens 550 to the other negative lenses to avoid the significant aberration caused by the incident rays.
The parameters of the lenses of the fifth embodiment are listed in Table 9 and Table 10.
TABLE 9
f = 3.07211 mm; f/HEP = 2.0; HAF = 50.0000 deg; tan(HAF) = 1.1918
Radius of
Thickness
Refractive
Abbe
Focal length
Surface
curvature (mm)
(mm)
Material
index
number
(mm)
0
Object
plane
infinity
1
Aperture
infinity
−0.17441
2
1 st lens
1.877
0.291633
plastic
1.583
30.2
5.66505
3
4.06658
0.316187
4
2 nd lens
−10.1091
0.409057
plastic
1.565
58
−100
5
−12.4837
0.051233
6
3 rd lens
5.92541
0.576756
plastic
1.65
21.4
10.9473
7
32.70513
0.182028
8
4 th lens
−2.6559
1.436919
plastic
1.565
58
1.81565
9
−0.88685
0.05
10
5 th lens
5.3738
0.719329
plastic
1.634
23.8
−1.9254
11
0.94863
0.6
12
Filter
infinity
0.2
1.517
64.2
13
infinity
0.362488
14
Image
infinity
plane
Reference wavelength: 555 nm
TABLE 10
Coefficients of the aspheric surfaces
Surface
2
3
4
5
6
k
−2.898419
2.201514
47.365798
49.999846
−50
A4
7.57889E−02
1.96262E−02
−2.77771E−02
−3.17649E−01
−3.05247E−01
A6
2.00574E−02
−5.11280E−02
−3.83429E−02
1.12207E−01
1.29093E−02
A8
−5.35177E−02
1.22456E−01
6.98240E−03
1.11784E−02
7.52215E−02
A10
1.12972E−01
−1.77441E−01
−1.07919E−02
−1.04300E−01
−4.10520E−01
A12
−1.07360E−01
6.61941E−02
−9.59444E−02
1.29766E−02
4.97363E−01
A14
2.22060E−02
−1.12144E−02
2.19634E−02
−1.95273E−02
−3.04967E−01
Surface
7
8
9
10
11
k
48.577511
−4.171536
−2.809738
−50
−5.295357
A4
−3.11560E−02
−1.71318E−02
−5.28008E−02
−1.77724E−02
−1.06711E−02
A6
−4.89053E−02
2.16362E−02
−2.52606E−02
−2.36540E−02
−1.22919E−02
A8
3.06016E−02
−1.23317E−02
2.08644E−02
−7.86477E−03
5.10738E−03
A10
−1.08111E−02
4.09103E−03
−6.71711E−03
1.16802E−02
−9.07942E−04
A12
4.23316E−04
8.35031E−04
9.11449E−04
−3.81466E−03
7.46277E−05
A14
7.68035E−04
−3.92410E−04
3.81218E−05
3.89495E−04
−2.32533E−06
An equation of the aspheric surfaces of the fifth embodiment is the same as that of the first embodiment, and the definitions are the same as well.
The exact parameters of the fifth embodiment based on Table 9 and Table 10 are listed in the following table:
Fifth embodiment (Reference wavelength: 555 nm)
InRS11
InRS12
InRS21
InRS22
InRS31
InRS32
0.17441
0.08278
−0.09107
−0.30013
−0.30136
−0.21631
InRS41
InRS42
InRS51
InRS52
HVT51
HVT52
−0.27577
−1.23371
−0.70347
−0.12434
0.84832
1.86249
|ODT|
|TDT|
InRSO
InRSI
Σ|InRS|
2.09505
0.81365
1.54608
1.95727
3.50335
Σ|InRS|/
Σ|InRS|/
(|InRS32| + |InRS41|)/
(|InRS42| + |InRS51|)/
InTL
HOS
IN34
IN45
0.86864
0.67429
2.7033
38.7436
(|InRS41| + |InRS42| + |InRS51| +
(|InRS41| + |InRS42| + |InRS51| +
|InRS52|)/InTL
|InRS52|)/HOS
0.57952
0.44986
|f/f1|
|f/f2|
|f/f3|
|f/f4|
|f/f5|
|f1/f2|
0.54229
0.03072
0.28063
1.69202
1.59557
0.05665
Σ PPR/|Σ
Σ PPR
Σ NPR
NPR|
Σ PP
Σ NP
f1/Σ PP
2.51494
1.62629
1.54642
18.42800
−101.92540
0.30742
HVT52/
HVT52/
|InRS51|/
|InRS52|/
f5 Σ NP
IN12/f
HOI
HOS
TP5
TP5
0.01889
0.10292
0.4980
0.3585
0.9780
0.1729
InTL
HOS
HOS/HOI
InS/HOS
InTL/HOS
Σ TP/InTL
5.19563
4.03314
1.38921
0.96643
0.77626
0.85137
HVT41
HVT42
1.47069
0
The exact parameters of the inflection points of the fifth embodiment based on Table 9 and Table 10 are listed in the following table:
Fifth embodiment (Reference wavelength: 555 nm)
HIF121
0.74702
HIF121/
0.19974
SGI121
0.07188
|SGI121|/(|SGI121| +
0.19775
HOI
TP3)
HIF311
0.20619
HIF311/
0.05513
SGI311
0.00299
|SGI311|/(|SGI311| +
0.00515
HOI
TP3)
HIF321
0.25733
HIF321/
0.06880
SGI321
0.00086
|SGI321|/(|SGI321| +
0.00149
HOI
TP3)
HIF322
1.33054
HIF322/
0.35576
SGI322
−0.17387
|SGI322|/(|SGI322| +
0.23163
HOI
TP3)
HIF411
1.03535
HIF411/
0.27683
SGI411
−0.18492
|SGI411|/(|SGI411| +
0.11402
HOI
TP4)
HIF421
1.47016
HIF421/
0.39309
SGI421
−0.96954
|SGI421|/(|SGI421| +
0.40289
HOI
TP4)
HIF511
0.51071
HIF511/
0.13655
SGI511
0.02040
|SGI511|/(|SGI511| +
0.02758
HOI
TP5)
HIF521
0.75392
HIF521/
0.20158
SGI521
0.19949
|SGI521|/(|SGI521| +
0.21711
HOI
TP5)
Sixth Embodiment
As shown in FIG. 6A and FIG. 6B , an optical image capturing system of the sixth preferred embodiment of the present invention includes, along an optical axis from an object side to an image side, a first lens 610 , an aperture 600 , a second lens 620 , a third lens 630 , a fourth lens 640 , a fifth lens 650 , an infrared rays filter 670 , an image plane 680 , and an image sensor 690 .
The first lens 610 has negative refractive power, and is made of plastic. An object-side surface 612 thereof, which faces the object side, is a convex aspheric surface, and an image-side surface 614 thereof, which faces the image side, is a concave aspheric surface. The object-side surface 612 has an inflection point.
The second lens 620 has positive refractive power, and is made of plastic. An object-side surface 622 thereof, which faces the object side, is a convex aspheric surface, and an image-side surface 624 thereof, which faces the image side, is a convex aspheric surface.
The third lens 630 has positive refractive power, and is made of plastic. An object-side surface 632 thereof, which faces the object side, is a concave aspheric surface, and an image-side surface 634 thereof, which faces the image side, is a convex aspheric surface. The image-side surface 634 has an inflection point.
The fourth lens 640 has a positive refractive power, and is made of plastic. An object-side surface 642 , which faces the object side, is a concave aspheric surface, and an image-side surface 644 , which faces the image side, is a convex aspheric surface.
The fifth lens 650 has negative refractive power, and is made of plastic. An object-side surface 652 thereof, which faces the object side, is a concave aspheric surface, and an image-side surface 654 thereof, which faces the image side, is a convex aspheric surface. The image-side surface 654 has an inflection point.
The infrared rays filter 670 is made of glass, and between the fifth lens 650 and the image plane 680 . The infrared rays filter 670 gives no contribution to the focal length of the system.
The parameters of the lenses of the sixth preferred embodiment are |f 2 |+|f 3 |+|f 4 |=33.5491 mm; |f 1 |+|f 5 |=10.9113 mm; and |f 2 |+|f 3 |+|f 4 |>|f 1 |+|f 5 |, where f 1 is a focal length of the first lens 610 ; f 2 is a focal length of the second lens 620 ; f 3 is a focal length of the third lens 630 ; and f 4 is a focal length of the fourth lens 640 ; and f 5 is a focal length of the fifth lens 650 .
The optical image capturing system of the sixth preferred embodiment further satisfies TP 4 =1.1936 mm and TP 5 =0.4938 mm, where TP 4 is a thickness of the fourth lens 640 on the optical axis, and TP 5 is a thickness of the fifth lens 650 on the optical axis.
In the sixth preferred embodiment, the second, the third, and the fourth lenses 620 , 630 , and 640 are positive lenses, and their focal lengths are f 2 , f 3 , and f 4 . The optical image capturing system of the sixth preferred embodiment further satisfies ΣPP=f 2 +f 3 +f 4 =33.5491 mm and f 2 /(f 2 +f 3 +f 4 )=0.1012, where ΣPP is a sum of the focal lengths of each positive lens. It is helpful to share the positive refractive power of the second lens 620 to the other positive lenses to avoid the significant aberration caused by the incident rays.
In the sixth preferred embodiment, the first and the fifth lenses 610 and 650 are negative lenses, and their focal lengths are f 2 and f 4 . The optical image capturing system of the sixth preferred embodiment further satisfies ΣNP=f 1 +f 5 =−10.9113 mm; and f 5 /(f 1 +f 5 )=0.3956, where ΣNP is a sum of the focal lengths of each negative lens. It is helpful to share the negative refractive power of the fifth lens 650 to the other negative lenses to avoid the significant aberration caused by the incident rays.
The parameters of the lenses of the sixth embodiment are listed in Table 11 and Table 12.
TABLE 11
f = 3.06009 mm; f/HEP = 2.0; HAF = 50.0007 deg; tan(HAF) = 1.1918
Radius of
Thickness
Refractive
Abbe
Focal length
Surface
curvature (mm)
(mm)
Material
index
number
(mm)
0
Object
plane
infinity
1
1 st lens
3.50904
0.796742
plastic
1.514
56.8
−6.5946
2
1.59356
4.172675
3
Aperture
infinity
−0.36597
4
2 nd lens
2.36495
0.703695
plastic
1.565
58
3.39442
5
−9.20538
0.766828
6
3 rd lens
−3.96665
0.773956
plastic
1.565
58
26.056
7
−3.3475
0.128823
8
4 th lens
−19.1128
1.193613
plastic
1.565
58
4.09863
9
−2.11807
0.384924
10
5 th lens
−1.36773
0.49381
plastic
1.65
21.4
−4.31667
11
−3.02608
0.1
12
Filter
infinity
0.2
1.517
64.2
13
infinity
1.623541
14
Image
infinity
0.027363
plane
Reference wavelength: 555 nm
TABLE 12
Coefficients of the aspheric surfaces
Surface
1
2
4
5
6
k
−0.364446
−0.797073
−0.976489
45.184506
−4.955335
A4
3.03151E−03
2.47474E−02
1.19749E−02
1.53107E−02
−3.15766E−02
A6
3.11535E−04
1.09227E−03
3.29173E−03
−8.86750E−03
−7.36452E−03
A8
6.03641E−06
2.11777E−03
−1.41246E−03
1.63700E−02
9.93051E−03
A10
−1.90703E−05
−1.38673E−04
2.09487E−03
−9.72154E−03
−1.85429E−02
A12
1.68207E−06
−2.43097E−05
−1.07114E−03
1.55553E−03
8.34169E−03
A14
−4.42840E−08
5.42793E−07
4.80842E−05
4.47459E−04
−9.07537E−04
Surface
7
8
9
10
11
k
−4.26661
−17.215386
0.01572
−0.56999
−1.957095
A4
−2.02516E−02
−2.81080E−02
1.04073E−02
2.87988E−02
4.78950E−03
A6
−1.45844E−02
1.26828E−02
4.37395E−04
−1.68233E−04
−4.65598E−04
A8
1.47638E−02
−2.57367E−02
−8.83115E−04
−1.52077E−04
1.47492E−04
A10
−8.52821E−03
1.81999E−02
−2.21655E−04
2.58158E−05
−1.37919E−05
A12
−3.64995E−05
−8.19803E−03
−4.19162E−05
−6.96422E−06
1.27305E−06
A14
8.24445E−04
1.22153E−03
5.89942E−06
1.05801E−05
−1.66946E−07
An equation of the aspheric surfaces of the sixth embodiment is the same as that of the first embodiment, and the definitions are the same as well.
The exact parameters of the sixth embodiment based on Table 11 and Table 12 are listed in the following table:
Sixth embodiment (Reference wavelength: 555 nm)
InRS11
InRS12
InRS21
InRS22
InRS31
InRS32
1.85151
2.39057
0.36630
−0.08200
−0.32310
−0.42687
|InRS51|/
|InRS52|/
InRS41
InRS42
InRS51
InRS52
TP5
TP5
−0.37068
−1.05112
−1.19340
−0.63635
2.4167
1.2887
|ODT|%
|TDT|%
InRSO
InRSI
Σ|InRS|
1.99808
0.23490
4.10499
4.58691
8.69190
Σ|InRS|/
Σ|InRS|/
(|InRS32| + |InRS41|)/
(|InRS42| + |InRS51|)/
InTL
HOS
IN34
IN45
0.96053
0.79017
6.19108
5.83107
(|InRS31| + |InRS32| + |InRS41| +
(|InRS31| + |InRS32| + |InRS41| +
|InRS42|)/InTL
|InRS42|)/HOS
0.35932
0.29560
|f/f1|
|f/f2|
|f/f3|
|f/f4|
|f/f5|
|f1/f2|
0.46403
0.90151
0.11744
0.74661
0.70890
1.94278
Σ PPR/|Σ
Σ PPR
Σ NPR
NPR|
Σ PP
Σ NP
IN12/f
1.76556
1.17293
1.50526
33.54905
−10.91127
1.24399
HVT52/
HVT52/
f1/Σ PP
f5/Σ NP
HVT51
HVT52
HOI
HOS
0.10118
0.39562
0.00000
0.00000
0.00000
0.00000
InTL
HOS
HOS/HOI
InS/HOS
InTL/HOS
Σ TP/InTL
11.00000
9.04910
2.94118
0.54823
0.82265
0.43781
HVT41
HVT42
0
0
The exact parameters of the inflection points of the sixth embodiment based on Table 11 and Table 12 are listed in the following table:
Sixth embodiment (Reference wavelength: 555 nm)
HIF111
2.68797
HIF111/
0.718709
SGI111
1.25958
|SGI111|/(|SGI111| +
0.61254
HOI
TP1)
HIF321
1.35714
HIF321/
0.362872
SGI321
−0.35849
|SGI321|/(|SGI321| +
0.316563
HOI
TP3)
HIF521
1.81195
HIF521/
0.484479
SGI521
−0.454608
|SGI521|/(|SGI521| +
0.479333
HOI
TP5)
It must be pointed out that the embodiments described above are only some preferred embodiments of the present invention. All equivalent structures which employ the concepts disclosed in this specification and the appended claims should fall within the scope of the present invention. | A five-piece optical lens for capturing image and a five-piece optical module for capturing image, along the optical axis in order from an object side to an image side, include a first lens with positive refractive power having a convex object-side surface; a second lens with refractive power; a third lens with refractive power; a fourth lens with refractive power; and a fifth lens with negative refractive power; and at least one of the image-side surface and object-side surface of each of the five lens elements are aspheric. The optical lens can increase aperture value and improve the imagining quality for use in compact cameras. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. patent application Ser. No. 10/871,557, filed Jun. 18, 2004.
FIELD OF THE INVENTION
[0002] This invention relates to flexible protective barriers which may be temporarily or permanently erected to protect buildings and occupants or other structures from the effects of high velocity winds or shock waves, with associated debris, resulting from natural phenomena, such as wind storms, and man made events, such as, explosive blasts.
[0003] 2. Description of the Prior Art
[0004] As is known by one skilled in the art of protecting buildings and the like from damage caused by missile-like objects that are occasioned by the heavy winds of hurricanes or tornadoes, there are commercially available variations of hurricane protective devices, often called shutters, that fasten immediately over the frangible area to be protected. These devices are typically expensive to purchase, cumbersome, made from stiff, heavy material such as steel and aircraft quality aluminum alloy or occasionally reinforced plastic. Many shutters need to be manually connected and then removed and stored at each threat of inclement weather. Many others require unsightly and difficult-to-mount reinforcing bars at multiple locations. Further, these known shutters are usually opaque, preventing light from entering a shuttered area and preventing an inhabitant from seeing out. Likewise, it is desirable that police be able to see into buildings to check for inhabitants and to prevent looting which can be a problem in such circumstances. Missiles, even small not potentially damaging missiles, striking these heretofore known shutters create a loud, often frightening noise that is disturbing to inhabitants being protected.
[0005] There are many patents that teach the utilization of knitted or woven fabric such as netting, tarpaulins, drop cloths, blankets, sheets wrapping and the like for anchoring down recreational vehicles, nurseries, loose soil and the like. Other protection devices use fabric or netting material to cover a unit to be protected. Typically, the device completely covers the unit, and edges of the fabric are fastened to the ground. Examples of fabric-employing devices are shown in the following patents: U.S. Pat. No. 3,862,876 issued to Graves, U.S. Pat. No. 4,283,888 and U.S. Pat. No. 4,397,122 issued to Cros, U.S. Pat. No. 4,858,395 issued to McQuirk, U.S. Pat. No. 3,949,527 issued to Double et al., U.S. Pat. No. 3,805,816 issued to Nolte, U.S. Pat. No. 5,522,184 issued to Oviedo-Reyes, U.S. Pat. No. 4,590,714 issued to Walker and U.S. Pat. No. 5,347,768 issued to Pineda. The U.S. Pat. No. 5,522,184 for example, provides a netting that fits flush over the roof of a building and uses a complicated anchoring system to tie down the netting.
[0006] What is needed in the art is a wind, rain and debris protective system, for individual openings, that can be installed during the construction of a building, either on the inside or outside of windows and doors or can be added to existing structures.
SUMMARY OF THE PRESENT INVENTION
[0007] A kit for protecting openings in a structure from penetration by debris, rain, and the force of high wind. The basic kit employs a polypropylene, woven monofilament geotextile material for use in temporary coupling to a structure opening, such as a window opening. The basic kit includes fasteners that secure the material over the opening and, should the opening be breached such as when a window is broken, the material maintains the envelope of the structure.
[0008] Alternatively the material can be used in combination with a retainer permanently secured to the structure wherein the material is temporarily placed into the retainer. In a preferred embodiment, the retainer has a flat flange with a channel on one edge and a longitudinal slit. The flat flange is adapted to cooperate with fasteners to connect the retainer to the structure with said channel extending parallel with the openings, and a flexible material with reinforced margins. The reinforced margins include a slide adapted to telescopically engage the channel with the material in the slit whereby the flexible material spans the openings when the slide is secured in the channel.
[0009] Thus, an object of this invention is to provide a barrier made from flexible material to protect the weak portions of the structure envelope including but not limited to, EIFS walls, windows, covered sections and openings of a building and the like from the force of wind, rain and impact from wind-borne debris.
[0010] Another objective of this invention is to provide the use of a retainer for securing the two opposing edges of a wind barrier material to retainer anchors located so as to form a structure envelope about the openings with the barrier spanning the opening.
[0011] Another object of this invention is that it may be sold as an after market kit to be installed on existing structures.
[0012] Yet another object of this invention is that it can be included in manufactured components, such as windows and doors, for installation in new or existing structures.
[0013] A further object of this invention is that the material fabric can be installed as an integral part of a structure during new construction.
[0014] Other objectives and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a plan view of a manufactured window with an integral material fabric;
[0016] FIG. 1A is a plan view of a manufactured window with an integral material fabric spaced apart from the window pane by a storm bar;
[0017] FIG. 1B is a plan view of a manufactured window with an integral material fabric space apart from the window pane by an inflatable bag;
[0018] FIG. 2 is a cross section of a structure constructed with the retainer in the enclosed space;
[0019] FIG. 2A is a cross section of a structure constructed with a retainer fastened into the header providing a flashing for the window frame;
[0020] FIG. 3 is a cross section of a structure constructed with the retainer outside;
[0021] FIG. 3A is a cross section of a structure constructed with the retainer fastened into the header providing a flashing for the window frame;
[0022] FIG. 4 is a perspective of a window of a structure with a retrofitted material fabric in place;
[0023] FIG. 5 is a perspective of a retainer for the material fabric;
[0024] FIG. 6 is a perspective of an alternative retainer;
[0025] FIG. 7 is a perspective of a supply roll of the material fabric; and
[0026] FIG. 8 is a perspective showing the reinforced margin of the material fabric.
DETAILED DESCRIPTION OF THE INVENTION
[0027] This invention contemplates the use of a flexible barrier, preferably a reasonably transparent, woven synthetic textile material that is able to satisfy stringent testing requirements. The flexible material is capable of withstanding high impact loads without bursting, can be disposed in front of a window or door intended to be protected, and anchored on opposing edges by either direct fastening to the walls of the structure or by use of a retainer for anchoring. Once the material is anchored it is able to contain the impact of foreign objects hurled by the high winds.
[0028] When the kit is used with a building, for example, the kit may include retainers that are permanently fastened to the top of a window or door and the bottom of the window, door, or opening. The fabric material may then include a flexible rod formed integral with the material along the opposing edges that is slidably secured into the retainer. Alternatively, the fabric may be anchored at the opposed sides of the window or door. Knitted or extruded material can be used if the material itself meets the criteria described later herein.
[0029] Although air travels through the material 11 , the barrier is approximately 95% closed, and the velocity of wind passing is greatly reduced and passage of rain effectively stopped. The preferred embodiment has interstices such that rain sheets on the barrier or air flow through the barrier is reduced or stopped. For example, the velocity of a 100 mph wind is reduced by approximately 97% by passing through the fabric material 11 of the present invention. The material fabric of the present invention substantially reduces the force of wind passing through the fabric material and also provides protection against wind-borne missiles having diameters of approximately 3/16 inch in diameter or larger. The ability to provide protection from wind forces and solid debris in the form of an envelope structure represents a step forward in this field. Further, the barrier maintains integrity of the structure, even if the frangible portions of the opening are broken.
[0030] The use of the barrier allows very large areas with spans of greater than 25 feet to be covered with ease. Thus, most window groupings could be readily protected. This invention is light in weight, easy to use, does not require reinforcing bars, can be constructed in varying degrees of transparency, can be weather tight, is economical, and is capable of dissipating far greater forces without damage than stiff devices. Missiles striking this barrier make very little sound.
[0031] The material 11 does not have rigidity but rather is very flexible, which gives several positive features including allowing for ease of storage as by rolling or folding. Also, the material fabrics may be easily installed by sliding the reinforced margins through the channels. The flexible barrier may be placed a distance out from the surface to be protected to prevent window breakage. However, if the barrier is not distanced from the surface from the window, an impact may cause loss of the window, the material maintains the structure envelop to prevent total loss of the building, which typically occurs when the structure envelop integrity is breached and high winds are allowed inside the structure.
[0032] In operation, an impacting missile stretches the material fabric until it decelerates to a stop or is deflected. The fabric material has a predetermined tensile strength and stretch that makes it suitable for this application. Said known strength and stretch, together with the speed, weight and size of the impacting missile, all of which are given in test requirements, permit design calculation to ascertain barrier deflection at impact. This deflection is a determinate of the optimum distance that this barrier is to be spaced out from the frangible area to be protected. Other determinates which may be included are additional deflection from wind pressure and from slack from an improper installation.
[0033] If the decision is to position the barrier out a distance from a window, the frangible surface need not be great and may be sufficient without the use of a standoff. If the window is proximate the outside wall of the structure, or is a large window, the distance can be ascertained which permits a time of deceleration such that the barrier will stop far stronger impacts than with the heretofore known rigid devices. In simple terms, the missile is slowed to a stop by elasticity as the barrier stretches. The greater the impact, the greater the stretch. Thus the building is not subjected to an abrupt harsh blow as the impact on the shutter is transferred to the building. The energy transfer is much gentler and less destructive than with the rigid devices.
[0034] The interstices of the material fabric permit the light to pass through and is reasonably transparent. If transparency is not desirable, the fabric can be made sufficiently dense to minimize or eliminate the interstices. To assure a long life, the material of the fabric preferably would be resistant to the ultra violet radiation, and to biological and chemical degradation such as are ordinarily found outdoors. This invention contemplates either coating the material or utilizing material with inherent resistance to withstand these elements. A synthetic material such as polypropylene has been found to be acceptable. An example of a coated material is vinyl coated polyester. Materials intended to be used outdoors in trampolines, for example, are likely candidates for use in this invention. Black colored polypropylene is most resistant to degradation from ultra violet radiation. Other colors and vinyl coated polyester are sufficiently resistant, particularly if the barrier is not intended to be stored in direct sunlight when not in use.
[0035] The material fabric of the instant invention allows air passage through it when dry, albeit at substantially reduced rate. Moisture on the fabric further reduces air passage. An upwind over pressure of 1″ of mercury, which roughly translates into a 100 mph wind, forces air through at 250 cubic feet per minute (cfm) or approximately 3 mph. The amount of air passage depends on the interstice size. If further protection is desired, the polypropylene material may be laminated with a flexible plastic skin.
[0036] It is of importance that the material affords sufficient impact protection to meet the regulatory agencies' requirements in order for this to be a viable alternative to other hurricane protective mechanisms. While stiff structures, such as panels of metal, are easily tested for impact requirement and have certain defined standards, fabrics on the other hand, are flexible and react differently from stiff structures. Hence the testing thereof is not as easily quantified as the stiffer materials. However, certain empirical relationships exist so that correlation can be made to compare the two mediums. Typically, the current impact test of certain locales requires a wood 2×4 stud be shot at the barrier exerting a total force of approximately 230 pounds, or 61.3 pounds per square inch (psi), over its frontal (impacting) surface. This impact and resultant force relate to the Mullen Burst test commonly used by manufacturers to measure the bursting strength of their fabrics. Thus the impact test heretofore used on rigid devices will work equally well on this flexible device.
[0037] The preferred embodiment of this invention would use a textile having at least a burst pressure of 675 psi or a total of 2,531.25 pounds over the same 3.75 square inch frontal surface of the nominal 2×4 test missile and would stretch 21% immediately prior to failure. The strength and stretch characteristics of the material are known. The strength of this fabric is more than eleven (11) times the 230 pounds of strength required to withstand the above-described 2×4 missile test as presently required by said regulatory agencies. Stronger fabrics are available. Others are available in various strengths, colors and patterns.
[0038] In the alternative embodiment, the use of flexible fabric material distanced out from the frangible area as a protective barrier allows extended deceleration. When the strength and stretch properties of the fabric are known and allowed for, the extended deceleration becomes controlled.
[0039] The material fabric 11 of this invention is easy to install, requires low maintenance and has low acquisition cost. There is much flexibility with storage. It is preferable but not essential, that the material selected to be used in the material fabric of this invention be inherently resistant to elements encountered in the outdoors or can be coated with coatings that afford resistance to these elements. A suitable material is polypropylene formed in a monofilament and woven into a geotextile (style 20458 ) manufactured by Synthetic Industries of Gainesville, Ga. The fabric is woven in a basket (plain) weave as shown in FIG. 5 where the fill and warp threads alternately cross over and under adjacent fills and warps. In the preferred embodiment the interstices are substantially equal to 0.6 millimeters. In the basic embodiment, the interstices allow the insertion of a fastener such as a tapcon screw without damage to the material. The interstices move to allow insertion of the fastener screw without damage to the material.
[0040] The material selected must meet certain strength criteria. These criteria, together with the size of span covered by the barrier, constitute the basis for calculating the deflection of the barrier. Said deflection is calculated as follows:
[0041] 1) The fabric must be sufficiently strong that the impact force it is required to withstand is less than the failure force (Mullen Burst).
[0042] 2) The impact (test) force is then divided by the force required to cause failure (Mullen Burst). This quotient is then multiplied by the known stretch at failure to obtain the stretch factor. The woven polypropylene synthetic fabrics of the type used in the preferred embodiment stretch 20-22% just prior to failure, depending on manufacturing technique. This stretch information is available from the manufacturer.
[0043] 3) The actual stretch measurement is then calculated and in conjunction with the span of the barrier used to ascertain the maximum deflection.
Example
[0044] The preferred embodiment is used as an example to demonstrate this formula. The preferred embodiment is a polypropylene, woven monofilament geotextile. The individual filaments are woven into a basket weave network and calendered so that the filaments retain dimensional stability relative to each other. This geotextile is resistant to ultra violet degradation and to biological and chemical environments normally found in soils. This fabric is often used as the mat for outdoor trampolines and is intended to be very resistant to weathering. The fabric is known to stretch a maximum of 21% prior to failure and requires a force of 675 psi to fail.
[0045] 1. The present test that was originally legislated by Dade County Florida and may become the standard in the industry, requires the barrier to withstand a force of only 61.3 psi. Consequently the fabric meets and exceeds the first requirement of strength.
[0046] 1. The stretch factor calculation is (test load/maximum load×% stretch at maximum load=stretch factor) 61.3/675×21=1.9%. This becomes a constant factor insofar as this fabric and the Dade test remain involved. The calculation will change if any one or more of the strength, energy or stretch characteristics of the test or fabric are modified Likewise, it is known that stretch varies directly with force up to the maximum at failure. To calculate the actual stretch, the calculation is stretch factor×height=actual stretch. Therefore if the distance between the two fastened sides is eight feet (96 inches), the stretch measurement will be 96×1.9%=1.83″.
[0047] 2. To calculate the deflection, right triangles are used such that the hypotenuse is ½ of the sum of the height plus stretch (97.83/2=48.92″). The known side is ½ of the height (96/2=48″). Thus the deflection=the square root of the difference between the square of the hypotenuse less the square of the known side. This result is 9.4″ which is the maximum deflection on impact by test missile.
[0048] 3. Thus the barrier will deflect at least 9.4 inches if an eight (8) foot span is to be used. A longer span will require wider spacing, a shorter will require less. The table shown below reflects this deflection for various sample distances of span with this preferred fabric.
[0049] Table demonstrating relationship between Span and Maximum Deflection if spacing apart from a window is preferred.
[0000]
Height
Deflection
8 feet
9.4 inches
10 feet
11.8 inches
12 feet
14.1 inches
14 feet
16.5 inches
16 feet
18.8 inches
18 feet
21.2 inches
20 feet
23.5 inches
22 feet
25.9 inches
24 feet
28.2 inches
30 feet
35.2 inches
40 feet
47.0 inches
*The deflection may be interpolated for windows and doors of lesser or greater length.
[0050] As the deflection is intended to be minimum, and although the barrier is intended to meet or exceed test standards as opposed to warranting protection in actual situations which are difficult to predict, this invention can include an additional factor in the deflection to allow for maximum wind pressure. Arbitrarily assuming a 115 mph wind at 90 degrees to the barrier and assuming the barrier has been made weather tight with no air flow through the barrier to somewhat relieve pressure, and assuming the barrier is installed at sea level where air is densest, the additional pressure on the barrier will be 0.237 pounds per linear inch of span. This additional pressure can be resolved into a vector and added directly to the test force of 61.3 pounds. Thus an 8 foot barrier will have an additional (0.237×96=) 22.75 pounds added for a total of 84.05 pounds. A 40 foot barrier will have (0.237×480=) 113.76 pounds added for a total of 175.06 pounds. This number should be substituted into the above formula to give a more accurate calculation of deflection.
[0051] For example: an 8 foot barrier could deflect 10.9″ when allowing for a 115 mph wind factor rather than 9.7″ if the wind was not factored in. The deflection of a 40 foot barrier becomes 80.28″ (6.69°) rather than 47″ (3.9°). If the window is not necessary to salvage, deflection is not of concern as the fabric material will prevent loss of envelop integrity.
[0052] The fabric must be anchored in a suitable manner so as to absorb the loads without being torn from its support. While various hardware devices may be used to anchor the fabric in place, general criteria include stainless steel screws or nails 13 with sufficient pull out strength in both wood and concrete to withstand the stress created by the material fabric 11 . These criteria are merely exemplary and not limiting. Other anchoring hardware may be used to install the protective barrier of this invention.
[0053] In FIG. 1 , a manufactured window 14 , for use in new construction or as replacement in existing structures, is shown. The frame 15 is of a size to fit into a standard sized opening in a structure, such as a house or commercial building for habitation or business. The frame 15 includes the structural framework to connect the window to the structure within the opening. As illustrated, the retainer 16 is integrally connected to the window between the frame 15 and the window sashes 17 and 18 . During manufacture of the window, the retainer 16 is fastened to the casement by screws or nails before final assembly. Alternatively, the retainer may be attached to the outer edge of the casement so that the channel 19 is disposed between the edge of the opening and the outer edge of the casement. When the embodiment is in the vertical position, the use of a locking hasp 30 prevents the fabric material from sliding out of the retainer channel. FIG. 1A depicts the use of a rigid stand-off 80 that can be made of wood, aluminum or the like material. For instance, a 1″ by 6″ rigid material may be used to span an opening to maintain the material a fixed distance from the opening. Similarly, as depicted in FIG. 1B , an inflatable structure 86 may be placed over the opening to maintain the material a fixed distance from the opening. The inflatable structure can be a nylon or the like material that is easily stored and when needed can be inflated by the material covering to provide a spacing for protection of the opening.
[0054] In FIG. 4 , the manufactured window is shown installed in a building wall 40 . In this embodiment, the flat flange is attached to the outer surface of the frame 15 by fasteners 41 .
[0055] In FIG. 2 , the barrier is shown as a part of the original construction of a new building 50 , or otherwise integrated into the building facade. The building has an inner wall 51 and an outer wall 52 . The inner and outer walls are joined through an intermediate structural component 53 and a window 54 . The material fabric 11 is to be mounted in the enclosed space of the building with the flat flange 20 permanently connected to the intermediate component 53 between the intermediate component and the inner wall 51 . FIG. 2A depicts the retainer 16 with the flat flange 20 inverted which works as a flashing by attachment to the header.
[0056] In FIG. 3 , the building is constructed with the channel 19 on the outside of the frangible element and the flat flange 20 is permanently connected to the intermediate component between the intermediate component and the outside wall. In this embodiment, the flat flange 20 is formed with an angular extension 21 positioned either upward with channel 19 extending over the top of the opening or in a downward slope as depicted by channel 19 A wherein the longitudinal slit 22 A is placed over the opening for better drainage of water.
[0057] FIG. 3A depicts the retainer 16 with the flat flange 20 inverted which works as a flashing by attachment to the header, the angle further provides for water drainage.
[0058] The retainer 16 , shown in FIGS. 5 and 6 , is formed of a flat flange 20 , an angular extension 21 and a channel 19 . The channel 19 has a longitudinal slit 22 . The retainer may be made of various materials with the requisite strength and durability to withstand the conditions of use, such as stainless steel or aluminum. Polymers of the requisite strength may also be used. Preferably, the retainer, flange and channel are of one piece construction though modular construction may be used. As mentioned above, the retainer must withstand the stress generated by the material fabric 11 when under load. The flat flange 20 may be made with apertures 60 for the attaching screws or the holes may be drilled on site or the screws or nails may be punched through the flange. The angular extension 21 may be made in different configurations to accommodate the different installations required by building design. In FIG. 5 , a 45 degree angle is shown and, in FIG. 6 , a 90 degree angle is shown. Of course, there may be other designs, such as, straight, U-shaped or Z shaped and the angular extension may be bent or deformed, on site. The angular extension functions to align the barrier 10 with the perimeter of the opening shown in FIG. 4 , either top and bottom or side to side, and to provide spacing for deflection of the material fabric.
[0059] The channel 19 cooperates with the bead 23 to connect the retainer 16 and the material fabric 11 . The slots 22 may be oriented in the channels to face each other across the span of the material fabric 11 . This places the strain directly on the selvedge edge of the material fabric, the joint with the bead, and the opposite edges of the slots 22 . In the alternative, the slots may be rotated at an angle from each other so that the material fabric engages one edge of each slot continuously and reduces the strain on the selvedge and the bead.
[0060] In FIGS. 7 and 8 the material fabric 11 is illustrated. The material fabric 11 is flexible enough to be stored as a roll 70 or a series of rolls. The material fabric must be bendable to permit the ends of the beads to be threaded into the ends of the channels. The beads are then slid through the channels to cover the windows or doors with the material fabric. The material fabric has a selvedge edge 71 that may be folded over on itself, have a reinforcing tape sewn along the edge, or some other form of bonding to secure the edges. In addition to a selvedge edge, a reinforcing tape may be used. The bead 23 is bonded, sewn, stapled or otherwise fixed to the selvedge edge of the material fabric. The bead 23 may be metal or plastic with a continuous extension 72 intimately connected with the edge of the material fabric.
[0061] Depending on whether the barrier is purchased as part of new construction, or part of manufactured components, or as after market improvements, the end result places the retainers along two opposed sides of windows and/or doors, either inside or outside the building. The material fabrics are supplied either pre-cut to size or in a supply roll. Once the building is finished or the retainers installed, the sized material fabrics can be removably mounted quickly. The opposite beads are threaded into the opposed channels of the retainers and the material fabrics are slid into position covering the frangible elements of the doors and windows.
[0062] A number of embodiments of the present invention have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the invention is not to be limited by the specific illustrated embodiment but only by the scope of the appended claims. | In the event of hurricanes or man-made events causing high wind velocities and flying debris, a window or door material fabric is removably installed to protect the frangible elements of the openings and unsuitably protected portions of the envelope. The barrier has retainers fastened on opposite sides of an opening with a flexible material fabric extending between the retainers. Alternatively, the barrier can be secured directly to the structure providing envelop protection to the structure. | 4 |
BACKGROUND OF THE INVENTION
The number of solid cancers and lymphoid or blood cancers is stagnant and/or rises and chemotherapic treatments provide disappointing or very insufficient results. The major difficulty comes from the fact that chemotherapeutic agents are toxic and sometimes lethal. They inhibit the proliferation not only of malignant cells but also that of normal cells which makes it necessary to find selective agents, capable of acting by themselves or in combination, in order that the inhibiting erect toward undesirable cells predominates. Having at disposition agents that are highly selective so that side effects are held to the minimum is an important objective of cancer research.
The same problem of poor selectivity and undesirable side effects occurs in the application of radiotherapy.
Considerable efforts are also given to find chemical entities that would be active against viruses that cause diseases in humans, animals and plants. The known antiviral entities also are not sufficiently selective; in addition their number is much smaller than those known to be active against bacteria and fungi.
In the case of both malignancies and viruses, it would be desirable to find entities that are active and selective at the level of abnormal cells, e.g. that will usefully affect DNA or enzymes implicated in the proliferation of malignant or virus infected cells.
BRIEF DESCRIPTION OF THE INVENTION
I have found that naringin and naringenin, and pharmaceutically acceptable derivatives thereof, inhibit the growth of cancer cells. I have also found that these compounds do not substantially damage normal cells. This selectivity between cancerous and non-cancerous cells makes naringin and naringenin effective therapeutic agents for the treatment of cancers.
In preferred embodiments, naringin, naringenin, or a pharmaceutically acceptable ester or salt thereof, or mixtures of one or more of the foregoing, are admixed with a pharmaceutically acceptable carrier. The resulting pharmaceutical composition is then separated into unit dosages, and one or more units is administered to the patient at a given time. The dosage, manner of administration, and frequency and length of time for treatment, vary with the patient, and are chosen by the physician to assure the best contact of the cancerous cells with an effective concentration of the agent.
In another aspect of the invention, a patient whose cancer cells are resistant to chemotherapy or radiotherapy is treated with an agent of this invention. I have found that these agents can be effective even against cancer cells which are resistant to chemotherapy and/or radiotherapy.
In still another aspect of the invention, it has been found that naringin and naringenin and their derivatives exhibit a synergistic effect when administered to animals or to patients undergoing conventional chemotherapy.
Another aspect of the invention resides in the discovery that naringin and naringenin provoke the contraction, i.e. closing, of DNA chains of cancer cells but not that of DNA chains of normal cells. The agents of this invention act on initiation sites of DNA of cancer cells, and also prevent the DNA chain elongation. It is believed that this causes in totality or partly the inhibition of growth of cancer cells. The closing of DNA chains prevents or inhibits the addition of deoxyribonucleotide units into the DNA molecule.
The fact that naringin and naringenin contract DNA chains from cancer cells suggests that in the acquired immune deficiency syndrome (AIDS) disease, induced by HIV virus, naringin and naringenin may prevent the formation of viral particles from "protooncogenes" which must modified during infection in order to produce virus. Thus, naringin and naringenin and their derivatives may be of value in the treatment of AIDS.
As far as planar and animal viral injection is concerned, naringin and naringenin administered to the host inhibit viral proliferation. This is believed due to their inhibiting the activity of certain enzymes present in or produced by the virus.
Yet another embodiment of the invention comprises a method for extraction of naringin and naringenin from natural vegetable (plant) sources.
THE DRAWINGS
FIG. 1 is the ultraviolet absorption spectrum of naringin commercially available and of naringin prepared by the method of this invention.
FIG. 2 shows the effects of naringin when tested using in vitro cultured human cancer and normal cells.
FIG. 3 shows the effect of naringin on the in vitro synthesis of DNA from normal cells and from cancer cells.
FIGS. 4a and 4b show the effect of naringin on the synthesis in vitro of DNA from cancer cells, when added at the start of synthesis and when added a period of time after the synthesis reaction has started.
FIGS. 5a and 5 b shows the effect of naringin, and of naringenin, in contracting cancer cell DNA chains but not contracting normal DNA chains, the extent of contraction being shown by hypochromicity.
FIG. 6 shows the effect or naringin and of naringenin on the activity of Terminal deoxynucleotidyl Transferase (TdT).
FIG. 7 shows a tobacco leaf infected with tobacco mosaic virus (TMV), one side of the leaf having been treated with naringin and the other side not treated.
FIGS. 8a and 8b show the structural formulae of naringin and naringenin, born being compounds known in the chemical literature.
FIGS. 9a and 9b and 10a, 10b, 10c, and 10d show synergistic action between classical antibiotics and naringin isolated by the described method of the present invention (Example 1). In these FIGS.: 5 FU =5-fluorouracil; JO-1=naringin Example 1; ARA-C=arabinoside cytosine; Endoxan= cyclophosphamide; HU=hydroxy-urea.
FIG. 11 is a drawing of a Table 1 which illustrates the survival of mice bearing cancer cells (lymphoma YC 8), untreated and treated by commercial naringin (i.p. route) and naringin-Example 1.
FIG. 12 is a drawing of a Table 2 illustrates the survival or mice bearing cancer cells (lymphoma YC8), untreated and treated by naringinExample 1 (i.m. route).
FIG. 13 is a drawing of a Table 3 which illustrates the survival of mice bearing cancer cells (Ehrlich carcinoma cells), untreated and treated by naringin according to Example 1 (i.p. route).
FIG. 14 is a drawing of a Table 4 which illustrates the survival of mice bearing cancer cells (lymphoma YC8), untreated and treated by commercial naringin (i.p. route).
DETAILED DESCRIPTION OF THE INVENTION
Both naringin and naringenin, as well as their derivatives, appear to act in two different ways on DNA of cancer cells. First, they contact or close DNA chains at the point of initiation or chain growth. Second, they contract or close DNA chains during chain elongation. These effects are probably the result of complementary strands of the DNA chain binding to each other through the added naringin or naringenin by covalent and/or hydrogen bonding. The closing of DNA chains of normal cells does not occur. It is believed that these phenomena contribute to or cause the selective inhibition of the growth of cancer cells, and the lack of inhibition of growth or normal cells, caused upon exposure of same to naringin or naringenin. However, I do not wish to be bound by this theory or any theory.
An amount of naringin, naringenin, or esters or salts thereof effective to inhibit the growth, i.e., proliferation, of cancer cells is administered to an animal (by animal include especially mammals, including humans) infected with cancer. A solution of these agents may be introduced intravenously, intraperitoneally, or intramuscularly, or orally as by tablet or capsule, or by rectal route, the physician choosing the manner of administration most suitable under the circumstances.
For humans, the dosages will generally fall within the following limits, but the physician may well go below or above these limits in particular cases.
Per os, i.e., by mouth, 1 to 3 grams agent per day. A naringin-acetone extract can be mixed with cellulose powder after pH is adjusted to neutral and dried at 60° to 70° C. for several hours, then pulverized in a Waring blender and placed in capsules, the concentration being such that about 0.5 gram naringin is present in each capsule. Two to six capsules per day may be used without any inconvenience for several months. The dosages will be about the same for the rectal route.
Naringin may be intramuscularly injected without disturbance into human beings or other animals. For humans, an intra muscular daily dose of 500-1000 milligrams for several consecutive days may be used. The naringin may be used in the form of a solution in small amounts of ethyl alcohol or other solvent such as dimethylsulfoxice (DMSO).
For intravenous injection or perfusion, 250-1000 milligrams daily come will generally be well tolerated. The agent may be dissolved in fresh DMSO and then further diluted with aqueous physiological solution to a final DMSO concentration of 5 to 10 percent.
For intravenous injection, the use of millipore filters as described in Example 1 is necessary. In preparing oral or rectal dosages, it is sufficient to use soluble extract (acetone and/or ether phase) after the pH adjustment to neutral values. In fact there is no toxicity in the commercial syrup used as source for amount. Naringin extract (acetone and/or ether phase) does not exhibit toxic effects on animals. Concentrated naringin extract can be mixed with cellulose powder dried, when pulverized and directly used :n capsules in a manner that each capsule contains one appropriate unit dosage amount (oral route), or embodied with wax for this purpose for suppository dosage (rectal route).
For viral infections, dosages of the same order of magnitude as those used in the treatment of cancer will be used; the same modes of administration may be used.
To prevent viral infections of plants or for post infection treatment, the active agent will be applied with a physiologically acceptable carrier, which may be liquid or solid, particularly adapted for adhesion to plant leaves or other paris of the plant (50 to 200 micrograms per leaf).
Extraction of Naringin from Plants
Example 1
Hippophae Rhamnoides
A commercially available syrup for humans containing large amounts of vitamin C and comprising about forty percent sugar and sixty percent extract of berry of the plant Hippophae Rhamnoides, was used as starting material. This syrup is available from Laboratories Weeua, 9 rue Eugene-Jung, 68330 Hungue, France.
To 500 millimeters of syrup, hydrochloric acid was added (final concentration 1 N) and the mixture was heated in a beaker for fifteen minutes at 100° C. After cooling the thus-hydrolyzed material, an excess of acetone was added (volume ×3 or 4 ). The mixture was mechanically shaken at room temperature. After a moment of standing, two phases appear. The acetone upper phase (yellow color) was removed and saved. Treatment of aqueous phase with acetone was repeated several times until acetone phase does not contain yellow color. Then several extractions were performed in the same manner with ether in order to extract the maximum of the active agent (naringin and naringenin).
The acetone phases were pooled, and distilled. The ether phases were pooled, and distilled. The distilled solvents may serve for further extractions. The acetone and ether residues were combined and pH adjusted to 7.0 (NaOH or KOH), and constitute highly concentrated naringin.
According to the form which will be given to the agent and the mode of administration, the agent will be or will not be further purified. If one decides on further purification, the acetone/ether residues are dissolved in a mixture of water-ethanol (1:1), the pH adjusted to 10-12 and the material filtered on millipor filters (0.45μ). The material remaining on millipor contains essentially pure naringin/naringenin. The filters were then incubated with 95° ethyl alcohol in a beaker with slight heating. The extraction with ethyl alcohol was repeated several times. The presence of naringin dissolved in the ethanol was determined by UV absorbance at different wavelengths (nm) which gives a characteristic spectrum, shown in FIG. 1. The preparation contains essentially naringin, and naringenin is probably present in small amount. Little or no vitamin C, sugar or lipids remain present in such a preparation.
Comparison with commercially available naringin used as standard (dissolution in ethyl alcohol) is then performed according to several criteria. The spectrum in UV absorption from 220 to 310 nm is determined by using 4 to 20 μg (micrograms) of naringin/milliliter. The spectrum of product isolated according to this Example 1 essentially coincides with that obtained for the reference naringin product. Illustration in FIG. 1. Naringenin has practically the same spectrum with maximum absorption (290 nm) as that of the reference solution.
On chromatography paper or silica gel plates, naringin isolated in this Example 1 migrates in the presence of ethanol as solvent, as does commercial naringin. Spots of both detected by UV light are in both cases close to the front of the solvent.
The same extraction and purification procedure has been applied directly to the Hippophae fruit.
The preparation of this Example 1 is more soluble in water and possesses a better biological activity compared with that exhibited by commercial compounds. This difference is probably due to the presence of small quantities of remaining sugars or lipids in the preparation.
Naringin prepared by the method illustrated in this Example has been given the name of "JO-1," and tests were done under that name.
Example 2
Citrus
Green lemon skin was peeled off and mixed with water and broken with a mixer. For isolation of naringin, the same procedure as above Example 1 was used. Certain grapefruits and oranges can also be used as a source for extraction of naringenin and naringin.
Example 3
Endive roots (Chicorum endivia)
Endive roots grown in earth are washed then peeled off and the peel not conserved. The roots are washed, cut into pieces and crunched with water in order to get an heavy soup-like mixture which is boiled for 30 min. at 100° C. The liquid is then filtered through a piece of woven material, vegetal fragments are re-extracted several times under the same conditions. The filtered liquids are pooled, concentrated and hydrolysed with hydrochloric acid (final concentration 1 N) for 10 min. at 100° C., then cooled. All other steps for purification are the same as those described above in Example 1.
Effects of Naringin and Naringenin
Example 4
The effect of naringin and naringenin has been detected according to an in vitro method which shows the action of a given substance on the replication process of DNA originating from either normal tissues or cancer tissues, as described in French patent application No. 7,728,208 of Sept. 19, 1977, which corresponds to U.S. Pat. No. 4,264,729 issued Apr. 28, 1981.
Results for naringin are presented in FIG. 3. They show that this product strongly inhibits in vitro synthesis of DNAs from different human cancer tissues, i.e. breast, colon and liver cancers, while that of DNAs from normal tissues (human bone marrow and spleen and monkey brain) is practically unaffected. This shows that naringin specifically interferes with cancer DNA but not with DNA polymerase. The same is true for naringenin. DNAs used were isolated from human cancer and normal tissues furnished by different hospitals as indicated in IRCS Medical Science 14: 809-810, 1986. The normal brain tissue originated from Macaca mulatta.
Example 5
The same test method was used on DNA from cancerous tissue, determining the amount of tritium-labeled DNA synthesized over a period of time and the effect of introducing naringin at different points in time. The results, illustrated in FIGS. 4a and 4b, show that naringin acts on DNA initiation sites when given at zero time of incubation, and also stops DNA chain elongation if added after the reaction starts.
Example 6
Naringin prepared in accordance with Example 1, and a commercial sample of naringenin prepared by Roth Co. of France, were used for comparison. The results of tests conducted as described below, displayed in FIGS. 5a and 5b show that both materials contract cancer cell DNA chains but have either no effect or a very slight effect on normal cell DNA. The results are expressed as decrease of UV absorbance (hypochromicity) in the presence of various concentrations of the agent. The hypochromicity corresponds to DNA chain contraction, while hyperchromicity would correspond to DNA chain opening (i.e. the breaking of hydrogen bonds which normally hold the two DNA chains together). The spleen and bone marrow DNAs used in this test were from normal human spleen and bone marrow tissue cells.
UV absorbance at wavelength of 260 nm for different DNAs from normal and cancer cells is performed at room temperature. 20 μg (micrograms) of DNA (deoxyribonucleic acid) are dissolved in 1 ml of Tris-HC1 buffer (10 -2 molar, pH adjusted to 7.3, solution made using sterile distilled water). The absorbance is measured before and after addition of either naringin or naringenin. The blank cuvette contains an equivalent amount of naringin or naringenin, but not DNA. The contact between DNA and compound is of about one minute (very slight agitation). The absorbance at 260 nm is then measured. The results are expressed as diminution (%) of UV absorbance.
Example 7
Naringin prepared in Example 1 has been used for determining its effect on in vitro cultured human cancer and normal cells, according to the method of Shoermaker R.H. et al., Cancer Research 45: 2145-2153, 1985). Culture medium contained 100 μg of penicillin and streptomycin in order to prevent bacterial contamination.
FIG. 2 shows results of this test, demonstrating the differential effect of various concentrations of naringin. Naringin strongly inhibits the various human cancer cells and has little effect on normal human bone marrow cells, and this in spite of a great sensitivity possessed by hematological cells to the effect of chemotherapeutic agents in general.
It is important to note that the ovary cancer cells* and leukemic cells* used in this Example were resistant to classical chemotherapy.
These results would indicate that naringin may sensitize cells resistant to chemo/radiotherapy by conventional therapeutic agents and, in all cases, these cells may be destroyed by using naringin and/or naringenin or their derivatives.
Example 8
The effect of naringin prepared according to Example 1, of commercial naringin and of commercial naringenin has been tested on tobacco mosaic virus (TMV). In this experiment, viral suspension containing 2 μg of virus/ml of distilled water, was incubated at 30° C. for 30 min. with each of the above compounds (20-50 micrograms per milliliter) and then 20 μl placed on one-half of the leaf (xanthy tobacco) while the same concentration of untreated virus was placed on the other half of the same leaf. The appearance of viral disease was checked two to three days later. By counting the "plaque" forming units (PFU), each corresponding to about 10 viral particles, it was observed that each of the added agents inhibits TMV multiplication. FIG. 7 shows the results of the test with naringin from Example 1. Naringenin or commercial naringin gave similar results.
Example 9
Both naringin and naringenin inhibit in vitro the activity of Terminal deoxynucleotidyl Transferase (TdT), an enzyme involved in the integration of viral genome into host cell. This enzyme is present in cat leucosis vaccine prepared by genetic engineering (Engerix® Leucocell vaccine), vaccine highly purified. I have previously shown that this enzyme catalyzes the polymerisation of d-TMP and d-CMP originating from d-TTP and d-CTP used respectively as substrates.
For testing the activity of TdT, the incubation medium (0.10 ml final volume) contains: 25 μmoles fresh solution of Tris-HC1 buffer pH 7.70; 2 μmoles MgCl 2 ; ( 3 d-NTP (deoxynucleoside-5'-triphosphate, 100,000 CPM). Increasing amounts of Leucocell vaccine (as indicated in FIG. 6) are used. Incubation for 10 minutes at 36° C., then addition of an equal volume of trichloroacetic acid (TCA 5%). Acid-precipitable material is filtered on millipore (Whatman GF/C), washed with 5% TCA then with 95° alcohol. After millipore drying, radioactivity of acid-insoluble material is measured in scintillation spectrometer Packard. The results are expressed as CPM (counts/minute)/sample.
FIG. 6 shows that both naringin and/or naringenin inhibit in vitro activity of TdT which contaminates commercial vaccine prepared from an RNA virus responsible for cat leucosis. In contrast, the activity of TdT which contaminates Engerix®-vaccine antigen B (Med. Sci. Res. 1987, vol.15 pp. 529-530), an antigen prepared from DNA virus is not inhibited, under the same conditions, by naringin or naringenin. Thus both naringin and naringenin selectively interfere with the proliferation of RNA virus but not DNA virus. However, as RNA from RNA-virus is transcribed into DNA by reverse transcriptase before being integrated into cell genome (potential role of TdT), naringin and naringenin are equally useful agents in treatment of all DNA infections equally.
Example 10
The effect of naringin on in vitro reverse transcriptase activity was determined. The reverse transcriptase commercially available from erythroblastosis virus (RNA virus) was used. The test was carried out as follows:
The reaction mixture (150 μl, final volume) contained 25 μM Tris-HC1 buffer, pH 7.7; 2 μM MgC1 2 ; 0.6 nM/each of deoxyribonucleoside-5'-triphosphates: deoxyadenosine-triphosphate (dATP), deoxycytidine-triphosphate (dCTP), deoxyguanosine-triphosphate (dGTP) and 0.6 nM 3 H-thymidine triphosphate ( 3 H-TTP, 100,000 CPM); 0.2-0.5μg globin m RNA (freshly prepared solution pH 6.5); 0.1 μg oligo dT 12-18 and 1-5 μg enzymatic protein. After 10 minutes incubation at 37° C. the reaction was stopped by adding an equal volume of cold trichloroacetic acid (TCA 10%) containing 0.02 M sodium pyrophosphate. The precipitate was filtered on glass filter Whatman (GF/A or GF/C), washed with 5% TCA containing 0.02 M pyrophosphate, then with ethyl alcohol 95° and finally dried. The radioactivity was measured in 5 ml of scintillation fluid with Beckman spectrometer. The radioactivity of acid precipitable material was determined.
The following table indicates the rate of inhibition when naringin of Example 1 is present in the incubation reaction in the presence of globin m RNA.
______________________________________ CPM of 3H-TMP incorporated in 10 min. % inhibition______________________________________complete mixture 1676 --+ naringin 25 μg 836 5050 μg 520 70150 μg 501 71______________________________________
EXAMPLE 11
This example illustrates the absence of toxicity of naringin or naringenin injected by intravenous route to BALB C mice. The fragility of mice veins did not permit to practice more repeated injections, either for toxicity or for tumor treatment by this route.
______________________________________Naringin (or Naringenin) i.v. Route (10% DMSO)(Example 1)______________________________________125 mg/kg no toxic effect250 mg/kg no toxic effect500 mg/kg no toxic effect______________________________________
One can conclude that naringin and naringenin may be administered either by i.v. injection or by perfusion at doses from 250-1000 mg/kg, doses well tolerated.
Example 12
The low affinity of naringin for normal cell DNA on one hand, for cells in vitro culture on the second hand, as well as the absence of toxicity in mice, are facts which suggest an absence of toxicity towards blood cells, white blood cells and platelets in particular.
A solution of naringin (Example 1) (10% DMSO in physiological solution) was injected (50 mg) to rabbits three times per week by intravenous route for two consecutive months. No change in blood analysis of animals treated in that way was detected, neither a loss of body weight.
Example 13
O BALB C mice bearing lymphoma YC8 (ascitic form) and Swiss mice bearing Ehrlich ascitic cells (20-22 grams, Charles River breeding) were distributed at random in sets of 10.
Each set received respectively:
Set I Control. Received tumor cells and NaC1 isotonic solution (0.2 ml/mouse, twice/day, i.p. route)
Set II: Mice bearing tumor cells received JO-1 (= naringin, Example 1): 0.2 ml/mouse, twice/day, i.p. route (for JO-1 concentrations, see Tables 1, 3, and 4, and FIG. 10.)
Set III: Mice bearing tumor cells received naringin (JO-1): 0.2 ml/mouse twice/day (for concentrations, see FIGS. 9 and 10), i.p. route and, at the same time these mice received a chemotherapeutic agent (for concentrations, see FIGS. 9 and 10) i.p. route.
Set IV: Mice bearing tumor cells received naringin (Example 1): 0.2 ml/mouse twice/day (for concentrations, see Table 2), i.m. route.
Ascitic tumor cells were taken in sterile medium from mice bearing these cells for 15-20 days. 0.1 ml of ascitic suspension was mixed with 10 ml of buffered solution (pH 7.2) : (NaCl 7.2 g/l; Na 2 HPO 4 4.3 g/l and KH 2 PO 4 0.4 g/l).
The number of cells was determined (by Malassez cell) and cellular suspension diluted in order to get cell number close to 40.000-50.000/ml. 0.1 ml of this suspension was immediately injected by i.p. route to mice in sets I, II and III and by i.m. route to mice in set IV.
Treatment: 48 hours after injection of tumor cells: the mice of set II received (i.p.) JO-1 heated at 37° and filtered on millipore, treatment for five consecutive days; the mice of set III were treated (i.p.) by a mixture of JO-1 and one of the antibiotics for 5 consecutive days; the mice of set I (control) received (i.p.) only isotonic solution for 5 consecutive days; the mice of set IV received (i.m.) JO-1 for 15 consecutive days.
Mice were observed for one month or two months after cessation of treatment. Only the survivors in excellent physical condition were taken into consideration .
It should be noted that Ehrlich ascitic cells are less sensitive to the effect of naringin than lymphoma YC8 cells. | Naringin and naringenin are disclosed as pharmaceuticals that selectively inhibit the growth of cancer cells in the presence of normal cells. They are also effective against cancer cells that are resistant to chemotherapy or radiotherapy. It is shown that naringin and naringenin selectively contract DNA chains of tumor cells but not DNA chains of normal cells. The subject compounds also exhibit anti-viral activity. A novel method for the recovery of naringin and naringenin from natural vegetable sources is taught. | 0 |
CROSS-REFERENCE TO RELATED APPLICATION
This application claims the benefit of U.S. Provisional Application No. 60/471,093, filed May 15, 2003.
FIELD OF THE INVENTION
This invention relates to a system for making a special receptacle or package, and more particularly to a system for making a reclosable sterile collection bag having a flexible strip closure mechanism.
BACKGROUND OF THE INVENTION
Bags having wire closure mechanisms are currently used to obtain industrial, chemical, and forensic material samples in a sterile manner. For example, U.S. Pat. No. 2,973,131 describes a collection bag having metal wires. Strips of pressure sensitive tape are used to attach the metal wires to opposite sides of the bag. Both the wires and the tape project beyond the side edges of the bag. During use, the bag is filled, the mouth of the bag is closed and rolled against the body of the bag, and the projecting portions of the metal wires are folded back to clamp the rolled end closed.
Later inventions have been made to improve the ease with which the bag may be opened. For example, U.S. Pat. Nos. 3,189,253; 4,356,954; and 5,180,220 each use center pull tabs. U.S. Pat. No. 4,356,954 uses downwardly-directed strip ends. U.S. Pat. No. 5,180,229 encloses the wire ends with an additional length of covering material. The arrangements of the above patents can be difficult and costly to manufacture. Other potential problems are pull tabs or tear strips that become separated from their bags and fall into (and therefore contaminate) foodstuffs or other products, and bags that are difficult to open or which may be punctured inadvertently.
SUMMARY OF THE INVENTION
The present invention provides a novel system for manufacturing a sterile collection bag having a body and an opening mechanism. The body is formed of opposed sidewalls and includes an upper body end portion adjacent to the mouth opening. The interior of the body defines a sterile collection space for a sample object or fluid. The opening mechanism includes first and second flexible closure strips, each having a first end, a second end, and a midsection. The strips can be constructed of plastic with an integrated, centrally located metal wire. The strips are attached to the sidewalls of the bag body and are longer than the width of the body so as to project beyond the sidewall edges. The projecting ends of the strips can be secured to one another.
The bag can be designed in such a way as to prevent the intrusion of air and other contaminants to the interior sterile collection space until its initial use, by sealing the top of the bag. For example, the bag can be formed of polymer film, and one or more lateral notches are cut slightly above the location of the attached flexible closure strips. The strips can be sufficiently rigid and abrupt to facilitate lateral tearing of the upper end of the bag, guided by an adjacent edge of a closure strip. This allows the top of the bag to be torn away for opening upon initial use, but prevents air and other contaminants from entering the interior sterile collection space beforehand.
In accordance with the present invention, bags of the type described above can be manufactured inexpensively and at high speed by automatic equipment including a placement component for rapidly moving individual bag blanks from a pack or magazine to a conveyor system in uniformly spaced relationship, and automatic equipment for applying opening tabs to opposite surfaces of the bag, followed by high speed application and cutting of the flexible closure strips. The manufacturing method preferably is conducted with the bag blanks moved continuously from the placement section to the high speed cutting section, as compared to incremental movement which could slow down the manufacturing process.
BRIEF DESCRIPTION OF THE DRAWINGS
The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:
FIG. 1 is a front elevation of a sterile collection bag that can be made by the system of the present invention;
FIG. 2 is a front elevation of a closure strip for use with the bag of FIG. 1 ;
FIG. 2A is a front elevation corresponding to FIG. 2 , showing an alternative closure strip that may be used;
FIG. 3 is an enlarged section along line 3 — 3 of FIG. 2 ;
FIG. 4 is a top perspective of a bag that can be made by the system of the present invention with some component parts shown in exploded relationship;
FIG. 5 is a top perspective corresponding to FIG. 4 , but with the parts assembled and the bag partially opened prior to use for collection of a sample;
FIG. 6 is a top perspective corresponding to FIG. 5 , with the mouth of the bag opened for insertion of a sample;
FIG. 7 is a perspective of a bag in accordance with FIG. 6 rolled and clamped closed to retain a collected sample therein;
FIG. 8 is a top perspective of an alternative bag partially opened;
FIG. 9 is a top perspective of the alternative bag with the mouth of the bag opened;
FIG. 10 is a diagrammatic side elevation of a pick-up and placement component used in a bag manufacturing system in accordance with the present invention, and FIG. 10A is a top perspective of a bag blank operated on by such component;
FIG. 11 is a diagrammatic side elevation of a tab-applying component used in a bag manufacturing system in accordance with the present invention, and FIG. 11A is a top perspective of a bag blank operated on by such component;
FIG. 12 is a diagrammatic side elevation of a closure strip-applying component used in a bag manufacturing system in accordance with the present invention; and FIG. 12A is a top perspective of a bag blank operated on by such component; and
FIG. 13 is a diagrammatic side elevation of a high speed cutting component used in a bag manufacturing system in accordance with the present invention, and FIG. 13A is a top perspective of a bag operated on by such component.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The present invention provides a system for manufacturing a bag that can be used in collection, processing, and manipulation of material samples taken for biological, industrial (such as food sampling) and forensic testing.
Referring to FIG. 1 , the bag 10 includes a body 12 formed of plastic or other known flexible, non-porous collection bag material. The body 12 includes opposed front and rear walls 14 and an upper body end portion 16 . Each sidewall 14 has an exterior surface and a center section. The bottom and side edges of the sidewalls are sealed, such as by conventional heat sealing or adhesive, represented by the cross-hatching along the bottom and side marginal portions. The top edge 17 also is sealed. The interior of the body 12 defines a sterile collection space for a sample to be placed. Notches 15 are provided at the side edges of the sidewalls 14 at the juncture between the bag body 12 and upper body end portion 16 . Preferably the upper body end portion 16 is brightly colored or otherwise prominently marked (represented by stippling in the drawings) so as to be readily visible when separated from the remainder of the bag structure as described below.
A flexible closure strip 22 usable with the bag of FIG. 1 is illustrated in FIGS. 2 and 3 . With reference to FIG. 3 , closure strip 22 has an essentially planar backside 23 which may be coated with a layer of adhesive 24 . A malleable wire 25 is embedded in a longitudinally extending rib 26 which preferably is located intermediate the top and bottom edges 27 , 28 of the strip. Thus, a substantial protrusion is provided on the front side 29 of strip 22 . Preferably the wire 25 is entirely surrounded and coated by the plastic material of the strip, so that no part of the midsection of the wire is exposed. The plane of the front side 29 of the strip, ignoring the rib 26 , is approximately aligned with the periphery of the embedded wire 25 .
The wire is a malleable metal, similar to wires used for common twist ties. In this construction, the plastic material also is a malleable material having little, if any, memory or spring characteristics, such that a double thickness of strips 22 can be easily bent to a new configuration and retain that configuration until bent back or bent to a new configuration. However, when in the flat configuration illustrated in FIG. 2 , at least the top edge 27 of the strip has sufficient thickness so as to be almost rigid as compared to the flexible bag material, with an abrupt corner or corners.
As described in more detail below with reference to FIGS. 10–13 , to facilitate bag manufacture and assembly by automatic machinery, long lengths of the closure strip 22 may be formed in rolls, prior to application of the adhesive coating 24 . Strips of a desired length can be cut from the roll and applied to the bag, all by the automatic machinery, but, in accordance with the present invention, continuous strips may be applied across multiple bags before the strips are cut. The wires 25 embedded in the pre-formed strips are reliably positioned as desired at the center of the strips. This alleviates the prior problem of misalignment of wires under paper tapes, direct contact of the wires with the bags, and exposed wires.
With reference to FIG. 4 , each strip 22 is applied to its bag with the top edge 27 of the strip extending between or close beneath the bag notches 15 . As see in the drawings, the front and back strips are in directly opposed relationship. Preferably the manner of attachment is adhesive applied along the midsection and projecting end portions 31 of each strip. Thus such end portions are secured together at their flat rear faces 28 . Opening tabs 30 have top end portions interposed between the strips 22 and the bag sidewalls 14 , and secured thereto by the adhesive. Such tabs have large projecting portions which preferably are square and approximately one inch in width by one inch in length, at least about ¾ inch in each dimension in the preferred embodiment. The projecting parts of these tabs 30 hang loose and are of a textured material suitable for writing indicia on them by a conventional writing instrument such as a pen or pencil, and of non-slippery material, i.e., with a sufficiently high co-efficient of friction that they may be readily grasped between a user's thumb and forefinger, for example, and pulled relatively apart as described below with reference to FIG. 6 .
With reference to FIG. 5 , the side notches breach the sheer strength of the plastic bag material providing a convenient starting point for a tear across the upper end portion 16 of the bag. Preferably the notches do not extend beyond the inner edge of the sealed area which would provide an opening into the interior of the bag that could cause contamination. The upper end portion is peeled downward along the top edge 27 of one or the other of the closure strips 22 , as shown in FIG. 5 . The sharp or abrupt top edge 27 of the strip 22 guides the tear and assists in assuring a clean, complete separation of the upper end portion 16 from the body 12 of the bag. The bag material can be a transversely oriented polymer, but an advantage of the invention is that a less expensive nonoriented polymer film can be used without scoring or partial perforation while still allowing the bag to be opened for use by tearing away the top end section 16 .
Typically, the bags are formed of a transparent or nearly transparent material, for visualization of any samples held therein. However, it has been found that upper tear strips of a transparent material may fall into the nearby environment, causing possible contamination. The brightly colored or otherwise prominently marked tear strip of the present invention is readily identified so that it will be retrieved if it is inadvertently dropped.
With reference to FIG. 6 , once the upper body end 16 has been tom from the bag, the mouth of the bag can be opened conveniently by pulling on the projecting tabs 30 . The desired sample S can be inserted through the open mouth of the bag. For the reasons discussed above, preferably the tabs 30 are brightly colored or otherwise prominently marked in case they become separated from the bag. Also, the non-slippery material, in combination with large tabs, make opening the bag mouth more convenient than in known designs, and the tabs provide a location for marking information concerning the contents, date of collection, etc.
After insertion of the sample S into the bag, the mouth is closed manually, rolled shut, and the projecting ends of the closure strips folded back onto the body of the bag to clamp it in the closed condition shown in FIG. 7 .
In the construction illustrated in FIGS. 8 and 9 , the projecting end portions 31 of the front and rear closure strips 22 are not secured together. The midsections of the strips, which can be less pliable than the strips of the previously described construction, are adhered to the bag body, but end portions 31 are unconnected so that they may diverge from each other at a small acute angle from the side edges of the bag to their free ends. Otherwise, the embodiment of FIGS. 8 and 9 is identical to the embodiment previously described. The top end part 16 can be torn beginning from a notch 15 along the abrupt top edge 27 of a strip 22 , as shown in FIG. 8 . Thereafter, the strip ends 31 can be squeezed together to bias the midsections of the strips apart as seen in FIG. 9 . If necessary to achieve a desired degree of opening, the strip ends at one side can be pushed toward the strip ends at the other, or the opening tabs can be used. After insertion of the sample, the mouth of the bag is closed, rolled, and clamped to the condition of FIG. 7 .
The ends of the strips 22 can extend straight and perpendicular to the top and bottom strip edges 27 , 28 as seen in FIG. 2 , for example. The plastic material has less tendency to puncture a bag, and the embedded wire is not exposed to a position where it substantially increases the prospects of a puncture.
In another construction, shown in FIG. 2A , the ends of strips 22 are formed with shallow recesses or central indentations 32 such that the wire ends are offset inward from the plastic strip ends 34 . The plastic ends are broader and more blunt than the wires, and less likely to cause unintended punctures.
FIGS. 10–13 illustrate automatic manufacture of sterile collection bags of the type described above. A placement component 32 picks up individual bag blanks 34 from a pack or magazine 36 and transfers the bags to a conveyor 38 . In a representative embodiment, this component can correspond to the model RPP-421 “pick and place” equipment of MGS Machine Corporation of Maple Grove, Minn., but other conventional “pick and place” machines can be used. The RPP-421 equipment includes a planetary drive for multiple pick-up heads 40 which include pressure-actuated pick-up members 42 . The pick-up members follow an epicyclic path from the pick-up point at the right of FIG. 10 through the position indicated at 44 to the position indicated at 46 where an individual bag blank is released onto the conveyor 38 . Pick-up and release of the blanks is timed and coordinated so that the spacing between adjacent bags is uniform. The conveyor 38 can have projections 48 which assist in providing the desired spacing, in combination with the timed release of a bag on the upper surface of the conveyor in synchronism with the conveyor drive. An individual bag blank 34 is shown in FIG. 10A , including the upper end portion 16 which is sealed, and the sealed side marginal portions. The bottom 50 of the bag blank is open in the illustrated embodiment, so that a desired sample, reagent, dilutent, etc. can be inserted after the bag manufacturing process described herein. For sample collection, the bottom 50 of the bag blank can be sealed from the outset.
From the constant speed, driven conveyor 38 , the bags are fed to another constant speed conveying mechanism 52 which includes upper and lower endless belts 54 and 56 . With reference to FIG. 11 , the upper belt 54 has a lower run 58 biased relatively toward the upper run 60 of the lower belt 56 . These two belts are positioned to grasp the bag blanks 34 at approximately their center portions, and slide the upper end portions of the blanks along a horizontal support and guide plate 62 . This plate is offset toward the viewer in FIG. 11 from the adjacent runs 58 , 60 of the belts 54 , 56 , but underlies the upper portions of the bag blanks. The opening tabs 30 ( FIG. 11A ) are applied by automatic equipment 64 as the bags are moved continuously in the direction of the arrow 66 . The equipment 64 is in the form of automatic label applicators such as the model 230 applicator of Accraply, Inc., of Plymouth, Minn. The tabs are provided on a backing roll 68 with only the end portions corresponding to the upper end portions of the tabs 30 having pressure sensitive adhesive. The backing strip is wound around feed and tension rollers to an applicator head 70 and applicator roll 72 . The applicator has an automatic product speed following feature such that a tab 30 is applied midway between the opposite side edges of each bag blank 34 . The first tab is applied by a first applicator unit at the top, where the upper end portion of the bag is supported on the plate 62 . The other tab is applied to the bottom surface by a second applicator component 64 which is offset downstream from the first unit and has its applicator head 70 and roller 72 aligned with an opening 74 through the plate 62 so that the bottom surface of the bag blank is exposed for a short distance. Following application of the tabs by the label applicators, the bare backing tape is wound on a take-up roll 76 . The condition of the bag following this procedure is illustrated in FIG. 11A , with the opening tabs 30 adhesively secured to the opposite walls of the bag, but only at the top end portions, leaving a free or hanging end portion of each tab.
With reference to FIGS. 12 and 12A , following automatic application of the oppositely located tabs, the belts 54 , 56 convey the bag blanks to components 78 for applying the flexible closure strips 22 . As noted above, long lengths of the closure strip material can be formed in rolls 80 with a continuous strip 22 guided past an adhesive applying nozzle 82 . Each of the units 78 correspond to a “tin tie” applicator available from Bedford Technology Division of Bedford Industries of Worthington, Minn., in combination with a series 3000V hot melt adhesive applicator available from Nordson Corporation of Duluth, Ga. At the top and at the bottom, a continuous strip 22 having the cross-sectional structure shown in FIG. 3 is routed around feed and tension rollers with the flat back of the strip 22 passing adjacent to one of the nozzles 82 where a continuous bead of adhesive is applied. From the nozzles, the strips 22 are brought together between pinch rolls 84 . This secures the top and bottom strips together at locations between the spaced bags being conveyed past the pinch rolls, and secures the strips to the bags in directly opposed relationship, as illustrated in FIG. 12A , for example, over the upper portions of the tabs 30 and along the upper end portions 16 of each bag blank 34 .
With reference to FIGS. 13 and 13A , following application of the continuous closure strip material, the bags 34 continue their travel by the center belts 54 , 56 to a high speed cutting mechanism 86 . The cutting mechanism quickly and precisely cuts the strips 22 midway between adjacent bags, resulting in the bag shown in FIG. 13A . In a representative embodiment, the high speed cutting mechanism includes a carriage 88 mounted on a rail 90 for movement back and forth in the direction of and contrary to the direction of travel of the bags 34 . Movement of the carriage is accomplished by a driven belt mechanism 92 . A knife 94 cooperates with an anvil 96 mounted on the carriage, and is actuated as the carriage is moved at the same speed as the bags and closure strips. More specifically, a sensor 93 detects passage of a bag 34 and actuates movement of the “flying knife” carriage in the direction of travel of the bag, with the knife and anvil positioned precisely between adjacent bags. The knife 94 is rapidly moved downward to cut the strip and back upward while moving in the same direction and at the same speed as the bags. The carriage then is quickly reciprocated back to the starting position for the next cutting operation.
After the quick and precise cutting of the closure strips 22 , the bags are fed to an exit conveyor 98 or other exit or collection mechanism. From the time of placement of the bags onto the first conveyor ( FIG. 10 ), to the final cutting operation ( FIG. 13 ), the bags preferably move continuously without stopping for any of the bag-forming operations.
While the preferred embodiment of the invention has been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention. | A placement component rapidly moves individual bag blanks from a pack or magazine to a conveyor system in uniformly spaced relationship. Each bag blank has opposite surfaces. While the conveyor system continues to move the bags, opening tabs are automatically applied to opposite surfaces of each bag, followed by high speed application and cutting of sideways extending flexible closure strips. The bag blanks are moved continuously from the placement component to the high speed cutting section, as compared to incremental movement, for high speed manufacturing of specialized bags. | 1 |
FIELD OF THE INVENTION
[0001] The invention relates to novel methods of anticholinergic therapy, particularly for respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD), without causing the class-related adverse effects of antimuscarinic compounds.
BACKGROUND OF THE INVENTION
[0002] Aclidinium (3(R)-(2-hydroxy-2,2-dithien-2-ylacetoxy)-1-(3-phenoxypropyl)-1-azoniabicyclo[2.2.2]octane) is a potent muscarinic receptor antagonist described, e.g., in WO 01/04118, WO 05/115467, WO 05/115466, and WO 05/115462 the contents of which applications are incorporated herein by reference. Aclidinium is a long-acting bronchodilator intended for administration by inhalation for treatment of respiratory diseases, especially asthma and COPD), currently in clinical trials.
[0003] Currently available muscarinic receptor antagonists include tiotropium ((1α,2β,4β,7β)-7-[(2-hydroxy-2,2-dithienylacetoxy]-9,9-dimethyl-3-oxa-9-azoniatricyclo[3.3.1.0 2,4 ]nonane), ipratropium ([8-methyl-8-(1-methylethyl)-8-azoniabicyclo[3.2.1]oct-3-yl]3-hydroxy-2-phenyl-propanoate), and glycopyrrolate ((1,1-dimethyl-2,3,4,5-tetrahydropyrrol-3-yl) 2-cyclopentyl-2-hydroxy-2-phenyl-acetate).
[0004] Acetylcholine is a neurotransmitter associated with parasympathetic innervation in the body and also with transmissions in the brain. It helps control the functioning of the heart, blood vessels, airways, and organs of the urinary and digestive tracts. It is also involved in memory, learning, and concentration. Antimuscarinic compounds inhibit the effects of acetylcholine on muscarinic receptors, which are by far the most common type of cholinergic receptors in the body. Compounds that inhibit acetylcholine activity at the M3 muscarinic receptors in the airways are very useful in the treatment of respiratory diseases, as they inhibit the acetylcholine-mediated contraction of smooth muscle in the airways, resulting in bronchodilation, and also reduce mucus secretion in the lungs.
[0005] One problem with the use of antimuscarinic compounds it the treatment of respiratory diseases, however, is the risk of side effects related to systemic suppression of cholinergic activity. These can include, for example, dry mouth, throat irritation, decreased sweating, increased pupil size, blurred vision, increased intraocular pressure, increased heart rate, chest pain, decreased gastric motility, constipation, difficulty starting and continuing to urinate, and loss of bladder control due to overflow incontinence. Anticholinergic activity can also have effects on the central nervous system, such as impaired concentration, confusion, agitation, anxiety, delirium, attention deficit, impaired memory, light-headedness, drowsiness, and respiratory depression. It has been found that cholinesterase inhibitors, which inhibit the breakdown of acetylcholine, are beneficial in
[0006] Alzheimer's disease and dementia, thus a physician may wish to avoid anticholinergic drugs in such patients if feasible. Acetylcholine has a complicated role in Parkinson's disease patients. It is believed to have a role in facilitating dopamine release, possibly through actions at the M4 and M5 muscarinic receptors in the brain, and on this basis, cholinesterase inhibitors are sometimes prescribed for Parkinson's patients; yet especially before the advent of levodopa, anticholinergics were used to treat the symptoms of Parkinson's disease, possibly by blocking the dopamine inhibiting activity of the M1 muscarinic receptors.
[0007] Older patients are more likely to experience undesired anticholinergic effects because their bodies produce less acetylcholine. Also, cells in many parts of the body (such as the digestive tract) in older patients may have fewer acetylcholine receptors. Thus, the acetylcholine produced is less likely to have an effect, and the effect of anticholinergic drugs is correspondingly greater. Moreover, older patients may have reduced kidney and/or liver function, and so may be prone to increased serum concentrations of many anticholinergic drugs. As discussed below, a number of commonly prescribed medications have anticholinergic effects, so patients who are taking multiple medications with anticholinergic side effects may be at elevated risk. Older men in particular may suffer adverse effects, because the urinary difficulties associated with anticholinergic activity may exacerbate or be exacerbated by an enlarged or obstructed prostate. Overall, anticholinergic side effects are among the most common drug-related negative effects experienced by elderly people.
[0008] Currently marketed antimuscarinics may be unsuitable for use in patients having a susceptibility to conditions that may be exacerbated by systemic anticholinergic effects. Levels of systemic anticholinergic activity that may be easily tolerated in a young, healthy person may be unacceptable in such patients. Conditions that may be exacerbated by systemic anticholinergic effects include schizophrenia, glaucoma, dry eyes, enlarged or obstructed prostate, narrowing or obstruction of the small intestine, enlarged colon, chronic constipation, enlarged lower esophagus, heart disease (especially any condition that may be aggravated by tachycardia, for example restenosis or plaque in the coronary arteries, propensity to arrhythmias, damage resulting from prior heart attacks, and congestive heart failure), Parkinson's disease, Alzheimer's disease, dementia, and myasthenia gravis. Antimuscarinics may also present special risks when co-administered with drugs which have anticholinergic effects, for example atypical antipsychotics or tricyclic antidepressants. Antihistamines, particularly first generation sedating antihistamines such as diphenhydramine, may bind muscarinic receptors in addition to histamine type-1 receptors, and so may also have anticholinergic effects. In extreme cases, anticholinergic drugs can trigger anticholinergic delirium, a medical emergency characterized by hot, dry skin, dry mucus membranes, dilated pupils, absent bowel sounds, and tachycardia. Finally, systemically active antimuscarinics may interfere with the action of drugs intended to enhance acetylcholine function, for example cholinesterase inhibitors and cholinergic agonists.
[0009] Accordingly, there is a need for antimuscarinic therapy, particularly for respiratory diseases, especially asthma and chronic obstructive pulmonary disease (COPD), which does not cause the class-related adverse effects of systemically active antimuscarinic compounds.
SUMMARY OF THE INVENTION
[0010] It has now been discovered that aclidinium may be used in the treatment of respiratory diseases without exposing patients to the class-related adverse effects of systemically active antimuscarinic compounds. Although aclidinium has the same ester moiety as, e.g., tiotropium (2-hydroxy-2,2-dithien-2-ylacetoxy), aclidinium administered by inhalation is surprisingly much more subject to degradation in plasma to its inactive acid and alcohol metabolites. Consequently, systemic exposure to the compound is negligible. Because of aclidinium's rapid metabolization, it is unlikely to result in undesirable systemic anticholinergic effects. Aclidinium nevertheless has a long duration of action at the receptor and is capable of providing long-acting benefits of antimuscarinic therapy to lungs and airways.
[0011] Accordingly, the invention provides, in a first embodiment, the use of aclidinium, in the manufacture of a medicament for use in the treatment or prevention of a respiratory disease or condition in a patient by inhalation, without producing in said patient systemic antimuscarinic effects.
[0012] Typically, the respiratory disease is a disease that may be treated, ameliorated or inhibited by a muscarinic receptor antagonist. More preferably, the respiratory disease or condition is selected from acute or chronic bronchitis, emphysema, asthma and chronic obstructive pulmonary disease, especially asthma and chronic obstructive pulmonary disease, most especially chronic obstructive pulmonary disease.
[0013] Typically, the patient is suffering from or susceptible to a condition which may be exacerbated by systemic antimuscarinic activity. More typically, the patient is suffering from or susceptible to one or more conditions selected from
[0014] a. schizophrenia, impaired concentration, confusion, agitation, delirium, attention deficit, impaired memory, respiratory depression.
[0015] b. glaucoma, dry eye, increased pupil size, blurred vision, increased intraocular pressure,
[0016] c. enlarged or obstructed prostate, difficulty urinating, overflow incontinence,
[0017] d. narrowing or obstruction of the small intestine, enlarged colon, chronic constipation, enlarged lower esophagus, decreased gastric motility, constipation,
[0018] e. dry mouth, throat irritation, impaired sweating
[0019] f. cardiovascular disease (including any of restenosis, arteriosclerosis, prior stroke or heart attack, congestive heart failure), arrhythmia, tachycardia,
[0020] g. Parkinson's disease, Alzheimer's disease, dementia, and/or
[0021] h. myasthenia gravis
[0022] Typically, the patient is a male. Further, the patient is typically over sixty years old.
[0023] In a further embodiment of the invention, the medicament is for administration to a patient who intends to drive or operate machinery during the course of treatment.
[0024] In a further embodiment of the invention, the patient is receiving a second drug which is a systemically active anticholinergic agent, or an agent which may cause or exacerbate any of the conditions listed above. Typically, the second drug is selected from antipsychotics, tricyclic antidepressants, and antihistamines.
[0025] In a further embodiment of the invention, the patient is receiving a drug which is intended to enhance acetylcholine function, e.g., a cholinesterase inhibitor or cholinergic agonist, e.g., as set forth below.
[0026] Typically, the aclidinium is in the form of a salt with an anion X, wherein X is a pharmaceutically acceptable anion of a mono or polyvalent acid. More typically, X is an anion derived from an inorganic acid, such as hydrochloric acid, hydrobromic acid, sulphuric acid and phosphoric acid, or an organic acid such as methanesulphonic acid, acetic acid, fumaric acid, succinic acid, lactic acid, citric acid and maleic acid. Preferably, the aclidinium is in the form of aclidinium bromide.
[0027] Typically, the aclidinium is in the form of a dry powder suitable for inhalation.
[0028] Typically, the medicament comprises a pharmaceutically acceptable carrier selected from mono-, di- or polysaccharides and sugar alcohols. Preferably, the carrier is lactose.
[0029] Typically, the systemic antimuscarinic effect to be avoided is selected from dry mouth, throat irritation, decreased sweating, increased pupil size, blurred vision, increased intraocular pressure, increased heart rate, chest pain, difficulty urinating, enlarged or obstructed prostate, decreased gastric motility, constipation, impaired concentration, confusion, agitation, delirium, attention deficit, impaired memory, and respiratory depression.
[0030] Typically, the patient receives one or more additional medication for treatment of the respiratory disease or condition. More typically, the additional medication for treatment of the respiratory disease or condition is selected from beta-adrenergic agonists, corticosteroids or glucocorticoids, PDE IV inhibitors, antihistamines, anti-IgE antibodies, leukotriene D4 inhibitors, inhibitors of egfr-kinase, p38 kinase inhibitors and/or NK1-receptor antagonists; e.g., selected from the compounds identified below. Preferably, the additional medication is selected from corticosteroids and/or beta-adrenergic agonists.
[0031] The invention further provides aclidinium, as defined above, or a medicament as defined above, for use in the treatment or prevention, by inhalation, of a respiratory disease or condition, as defined above, in a patient as defined above, without producing in said patient systemic antimuscarinic effects as defined above.
[0032] The invention further provides a method of treating or preventing, by inhalation, a respiratory disease or condition as defined above, in a patient in need of such treatment, which patient is as defined above, without producing in said patient systemic antimuscarinic effects as defined above, which method comprises administering to said patient an effective amount of aclidinium, as defined above.
DETAILED DESCRIPTION OF THE INVENTION
[0033] Medications which may have anticholinergic effects or make patients more susceptible to anticholinergic effects, include, for example,
[0034] a. Drugs for nausea or dizziness, especially anticholinergic agents, e.g., promethazine (Phenergan), prochlorperazine (Compazine), trimethobenzamide (Tigan), meclizine (Antivert), cyclizine (Marezine), scopalamine
[0035] b. Drugs for Parkinson's Disease, especially anticholinergic agents, e.g., benztropine; biperiden; procyclidine; trihexyphenidyl; ethoproprazine
[0036] c. Antidepressants, especially tricyclics, e.g., amitriptyline (Elavil), doxepin (Sinequan), imipramine (Tofranil), trimipramine (Surmontil), nortriptyline (Pamelor), protriptyline (Vivactil). amoxapine (Asendin), maprotiline (Ludiomil), clomipramine (Anafranil); desipramine (Norpramin)
[0037] d. Antihistamines, especially first-generation sedating antihistamines, e.g., diphenhydramine (Benadryl) chlorpheniramine (Chlor-Trimeton), hydroxyzine (Atarax/Vistaril), cyproheptadine (Periactin)
[0038] e. Muscle relaxants, e.g., metaxalone (Skelaxin) cyclobenzaprine (flexeril), orphenadrine (Norflex)
[0039] f. Certain anti-migrane medications, e.g., belladonna alkaloids
[0040] g. Certain anti-diarrhea drugs, e.g., diphenoxylate/atropine (Lomotil)
[0041] h. Urinary and GI Antispasmodics, e.g., oxybutynin (Ditropan), flavoxate (Urispas), dicyclomine (Bentyl), hyoscyamine; belladonna alkaloids; tolterodine (Detrol), trospium, clindinium; propantheline, pirenzepine, telenzepine,
[0042] i. Antiarrhythmic drugs, e.g., disopyramide (Norpace), procainamide (Pronestyl), quinidine, atropine
[0043] j. Antipsychotics, e.g., chlorpromazine (Thorazine), thioridazine (Mellaril), clozapine (Clozaril), fluphenazine (Stelazine), thiothixene (Navane)
[0044] Medications which enhance cholinergic activity, include
[0045] a. Reversible cholinesterase inhibitors, e.g., edrophonium, tacrine, donepizil, physostigmine, pyridostigmine, rivastigmine, galantamine, neostigmine,
[0046] b. Cholinergic agonists, e.g., methacholine, bethanachol, pilocarpine
[0047] Beta-adrenergic agonists that can be combined with aclidinium in the present invention particularly include β2 adrenergic agonists useful for treatment of respiratory diseases or conditions, for example, selected from the group consisting of arformoterol, bambuterol, bitolterol, broxaterol, carbuterol, clenbuterol, dopexamine, fenoterol, formoterol, hexoprenaline, ibuterol, isoprenaline, mabuterol, meluadrine, nolomirole, orciprenaline, pirbuterol, procaterol, reproterol, ritodrine, rimoterol, salbutamol, salmeterol, sibenadet, sulfonterol, terbutaline, tulobuterol, GSK-597901, GSK-159797, KUL-1248, TA-2005 and QAB-1491, in free or pharmaceutically acceptable salt form. Preferably, the β32 adrenergic agonist is a long-acting β2 adrenergic agonist, e.g., selected from the group consisting of formoterol, salmeterol and QAB-149 in free or pharmaceutically acceptable salt form.
[0048] Corticosteroids that can be combined with aclidinium in the present invention particularly include those suitable for administration by inhalation in the treatment of respiratory diseases or conditions, e.g., prednisolone, methylprednisolone, dexamethasone, naflocort, deflazacort, halopredone acetate, budesonide, beclomethasone dipropionate, hydrocortisone, triamcinolone acetonide, fluocinolone acetonide, fluocinonide, clocortolone pivalate, methylprednisolone aceponate, dexamethasone palmitoate, tipredane, hydrocortisone aceponate, prednicarbate, alclometasone dipropionate, halometasone, methylprednisolone suleptanate, mometasone furoate, rimexolone, prednisolone farnesylate, ciclesonide, deprodone propionate, fluticasone propionate, halobetasol propionate, loteprednol etabonate, betamethasone butyrate propionate, flunisolide, prednisone, dexamethasone sodium phosphate, triamcinolone, betamethasone 17-valerate, betamethasone, betamethasone dipropionate, hydrocortisone acetate, hydrocortisone sodium succinate, prednisolone sodium phosphate and hydrocortisone probutate. Budesonide and mometasone are especially preferred.
[0049] PDE 4 inhibitors that can be combined with aclidinium in the present invention include denbufylline, rolipram, cipamfylline, arofylline, filaminast, piclamilast, mesopram, drotaverine hydrochloride, lirimilast, roflumilast, cilomilast, 6-[2-(3,4-Diethoxyphenypthiazol-4-yl]pyridine-2-carboxylic acid, (R)-(+)-4-[2-(3-Cyclopentyloxy-4-methoxyphenyl)-2-pheraylethyl]pyridine, N-(3,5-Dichloro-4-pyridinyl)-2-[1-(4-fluorobenzyl)-5-hydroxy-1H-indol-3-yl]-2-oxoacetamide, 9-(2-Fluorobenzyl)-N6-methyl-2-(trifluoromethyl)adenine, N-(3,5-Dichloro-4-pyridinyl)-8-methoxyquinoline-5-carboxamide, N-[9-Methyl-4-oxo-1-phenyl-3,4,6,7-tetrahydropyrrolo[3,2,1-jk][1,4]benzodiazepin-3(R)-yl]pyridine-4-carboxamide, 3-[3-(Cyclopentyloxy)-4-methoxybenzyl]-6-(ethylamino)-8-isopropyl-3H-purine hydrochloride, 4-[6,7-Diethoxy-2,3-bis(hydroxymethyl)naphthalen-1-yl]-1-(2-methoxyethyl)pyridin-2(1H)-one, 2-carbomethoxy-4-cyano-4-(3-cyclopropylmethoxy-4-difluroromethoxyphenyl)cyclohexan1-one, cis [4-cyano-4-(3-cyclopropylmethoxy-4-difluoromethoxyphenyl)cyclohexan-1-ol, ONO-6126 (Eur Respir J 2003, 22 (Suppl. 45): Abst 2557) and the compounds claimed in the PCT patent applications number WO03/097613 and PCT/EP03/14722 and in the Spanish patent application number P200302613.
[0050] PDE4 antagonists that can be combined with aclidinium in the present invention include tomelukast, Ibudilast, pobilukast, pranlukast hydrate, zafirlukast, ritolukast, verlukast, sulukast, cinalukast, iralukast sodium, montelukast sodium, 4-[4-[3-(4-Acetyl-3-hydroxy-2-propylphenoxy)propylsulfonyl]phenyl]-4-oxobutyric acid, [[5-([[3-(4-Acetyl-3-hydroxy-2-propylphenoxy)propyl]thio]1,3,4-thiadiazol-2-yl]thio]acetic acid, 9-[(4-Acetyl-3-hydroxy-2-n-propylphenoxy)methyl]-3-(1H-tetrazol-5-yl)-4H-pyrido [1,2-a]pyrimidin-4-one, 5-[3-[2-(7-Chloroquinolin-2-yl)vinyl)phenyl)-8-(N,N-dimethylcarbamoyl)-4,6-dithiaoctanoic acid sodium salt; 3-[1-[3-[2-(7-Chloroquinolin-2-yl)vinyl]phenyl]-1-[3-(dimethylamino)-3-oxopropylsulfanyl]methy sulfanyl]propionic acid sodium salt, 6-(2-Cyclohexylethyl)-[1,3,4]thiadiazolo[3,2-a]-1,2,3-triazolo[4,5-d]pyrimidin-9(1H)-one, 4-[6-Acetyl-3-[3-(4-acetyl-3-hydroxy-2-propylphenylthio)propoxy]-2-propylphenoxy]butyric acid, (R)-3-Methoxy-4-(1-methyl-5-N-(2-methyl-4,4,4-trifluorobutyl]carbamoyl]indol-3-ylmethyl]-N-(2-methylphenylsulfonyl)benzamide, (R)-3-[2-Methoxy-4-[N-(2-methylphenylsulfonyl)carbamoyl]benzyl)-1-methyl-N-(4,4,4-trifluoro-2-methylbutyl]indole-5-carboxamide, (+)-4(S)-(4-Carboxyphenylthio)-7-[4-(4-phenoxybutoxy)phenyl]-5(Z)-heptenoic acid and the compounds claimed in the PCT patent application number PCT/EP03/12581.
[0051] The words “treatment” and “treating” are to be understood as embracing treatment and/or amelioration of symptoms of a disease or condition as well as treatment of the cause of the disease or condition. Reference to “prevention” of a disease embraces prophylaxis and/or inhibition of the disease.
[0052] Aclidinium for use in the methods of the invention may be administered by any suitable route to provide local antimuscarinic action. It is preferably administered by inhalation, e.g., as a powder, spray, or aerosol, preferably as a dry powder. Pharmaceutical compositions comprising aclidinium may be prepared using conventional diluents or excipients and techniques known in the galenic art. For example, dry powder formulations may contain a powder mix for inhalation comprising the aclidinium and a suitable powder base (carrier substance) such as lactose or starch. Use of lactose is preferred. Suitable inhaler devices are known in the art. Dosages will vary depending on, e.g., the individual, the mode and frequency of administration, and the nature and severity of the condition to be treated. Daily dosages for a 40 kg adult human may typically for example be on the order of 100-1000 micrograms of active agent in the form of dry powder for inhalation.
EXAMPLE 1
In Vitro Stability of Aclidinium Compared With Tiotropium And Ipratropium And Glycolpyrrolate Stability In Human Plasma
[0053] The in vitro experiments are carried out at 36° C. and at a concentration of 5 μg/ml (6 μl of a 1 mg/ml dimethyl sulfoxide solution of each substance is added to a final volume of 1.2 ml). After 3 minutes of pre-incubation, reaction is started by addition of the test substances. At pre-defined times of 0, 5, 15, 30 and 60 min., aliquots of 100 μl of the plasma are separated and the reaction stopped by the addition of 1 ml of a 20 mM, pH 4.0 sodium acetate buffer solution. The test substances are replaced with buffer for the control reactions. Human plasma is obtained from volunteers by written informed consent. The blood is collected in tubes containing lithium heparin as anticoagulant, immediately centrifuged at 4° C. and the resultant plasma stored at −20° C. when not in use.
[0054] The determination of aclidinium, tiotropium, ipratropium and glycolpyrrolate in human plasma (100 μl) is carried out by high-performance liquid chromatography (HPLC) using UV detection, at 238 nm for aclidinium and tiotropium, and 203 nm for Ipratropium, and an automated online solid-phase extraction and injection procedure. A suitable chromatographic system consists of a high-pressure pump (model 322 Kontron for aclidinium and tiotropium and model 515 Waters for ipratropium), a Prospekt system (Spark Holland) assisted by a 233XL sampling injector (Gilson Medical Electronics), a tunable absorbance detector (model 2487, Waters Ass.), and a Digital Alpha Server 1000 4/266 computer with Acces*Chrom software (Perkin Elmer Nelson Systems, Inc.). Chromatography for aclidinium and tiotropium determination is carried out on a Spherisorb ODS2, 5 μm, 150×4.6 mm column (Waters Ass.) with a Guardapack gBondapak CN Precolumn (Waters Ass.) and a mobile phase (50:50 v/v for ACLIDINIUM and 22:78 v/v for tiotropium) of acetonitrile: 20 mM, pH 3.0 sodium phosphate buffer solution containing 0.2% triethylamine at a flow rate of 1 ml/min. The approximate retention times for aclidinium and tiotropium are 9.8 and 9.5 minutes respectively. Chromatography for ipratropium determination is carried out on a Symmetry C18, 5 μm, 150×4.6 nun column (Waters Ass.) and a mobile phase (12:88, v/v) of acetonitrile:20 mM, pH 3.0 sodium phosphate buffer solution containing 0.2% triethylamine at a flow rate of 1 ml/min. The approximate retention time of tiotropium is 9.5 minutes. The extraction of aclidinium, tiotropium and ipratropium from plasma is performed on C2 cartridges (Baker) activated with 1.5 ml of acetonitrile and conditioned with 1.5 ml of water. Plasma samples, previously diluted with 1 ml of a 20 mM, pH 4.0 sodium acetate buffer solution, were loaded into the C2 cartridges. After washing out the cartridges with 1 ml of water and 1 ml of acetonitrile:water (40:60, v/v) for aclidinium, or 3 ml of water for tiotropium, or 1 ml of water and 1 ml of acetonitrile:water (10:90, v/v) for ipratropium, the remaining components are eluted with the mobile phase over 1 minute. There are no significant endogenous peaks at retention times of the analytes that would interfere with their quantitation. The recovery of aclidinium is about 95% from human plasma. The recovery of tiotropium and ipratropium from plasma is between 80-100%. Glycopyrrolate stability in human plasma is using essentially the same procedures as for the other three drugs. The lower limit of quantitation is established at 5 mg/ml for all analytes.
[0055] Aclidinium is rapidly hydrolyzed in human plasma in its alcohol and acid metabolites. Both metabolites of aclidinium are assayed on binding for M1, M2, M3, and M4 human muscarinic receptors and are devoid of significant affinity for these receptors. The plasma half life of aclidinium in plasma is lower than 5 minutes for human. Moreover, aclidinium is stable in acid aqueous solutions (pH≦4) and the hydrolytic cleavage of the ester bond takes place at neutral and basic pHs.
[0056] In contrast, the other three antirnuscarinic esters are quite resistant to degradation by esterases in plasma. Plasma degradation for tiotropium (16%), ipratropium (0%), glycolpyrrolate (9%) is not biologically significant during the time of this study (60 min).
EXAMPLE 2
[0057] Clinical Phase I study: Aclidinium bromide is tested in a Phase I, double-blind, partial cross-over, placebo controlled study to assess the activity, pharmacokinetics and tolerability of aclidinium.
[0058] Methods: 12 healthy male volunteers are randomly assigned to 1 of 4 treatment sequences comprising single doses of aclidinium (50, 300 and 600 micrograms) or placebo administered by dry powder inhaler. The washout period between administrations is at least 6 days. Efficacy endpoints are specific airway conductance (sGaw), airway resistance (Raw) and bronchial hyperresponsiveness (PC35 sGaw methacholine).
[0059] Results: Aclidinium significantly increases sGaw at all timepoints (1-24 h, p<0.001 vs placebo). Correspondingly, Raw is significantly decreased by aclidinium at all timepoints except 1 h and 24 h (pO.001 vs placebo). Aclidinium 300 and 600 micrograms also significantly reduces PC35 sGaw methacholine at all post-administration timepoints (p<0.001 vs placebo): the methacholine doses required to decrease sGaw by 235% were 142.7 and 181.7 vs 27.1 mg/mL, for aclidinium 300 and 600 micrograms vs placebo, respectively, at 24 h; and 207.1 and 256.0 vs 35.5 mg/mL, respectively, at 2 h. Neither aclidinium nor its metabolites are detected in plasma and no study-drug-related adverse events are reported.
[0060] Conclusion: Aclidinium produces significant and long-lasting protection against methacholine-induced bronchoconstriction in healthy male volunteers, demonstrating its suitability for once-daily dosing, notwithstanding that plasma levels are not even detectable.
EXAMPLE 3
[0061] Clinical Phase 11 study: A double-blind, randothised, placebo-controlled, cross-over trial assesses the pharmacodynamics, pharmacokinetics and tolerability of aclidinium and its effects in COPD patients
[0062] Methods: Men with COPD (FEV1<65% predicted) with demonstrated airway reversibility to ipratropium are randomised to 1 of 4 treatment sequences comprising single doses of aclidinium (100, 300 and 900 micrograms) and placebo administered by dry powder inhaler with a washout period of 1 week between doses. Lung function measurements include FEV1 and FVC.
[0063] Results: 17 males (mean age 63.5 y, mean FEV, 1.63 L) participate in the study. Aclidinium (100, 300 and 900 micrograms) significantly increases mean FEVi AUC(0-24)/24 compared with placebo (1.800 [p=0.002], 1.798 [p<O.OOO1] and 1.827 [pO.OOO1] L vs 1.597 L, respectively). The increase in FEVI are statistically significant at 24 h for all doses. Aclidinium 300 and 900 micrograms produces greater peak FEV1 effects and the time to maximal onset occurres earlier than with the 100 micrograms dose. Similar trends are seen with PVC. No plasma levels of aclidinium or its alcohol metabolite are detected; low levels of its acid metabolite can be detected following the 900 microgram dose. Aclidinium is well tolerated: only 6 cases of mild or moderate headache (vs 2 with placebo) and 1 of mildly increased sweating appear possibly related to treatment.
[0064] Conclusion: Single doses of aclidinium (100, 300 and 900 micrograms) produce a rapid and long-lasting bronchodilation in patients with COPD, notwithstanding that plasma levels are not detectable. | The invention provides methods of inhalation treatment of a respiratory disease or condition in a patient in need to such treatment without producing in said patient systemic antimuscarinic effects, comprising administering to said patient an effective amount of aclidinium. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to valves and is particularly concerned with valves for use in conventional domestic, agricultural and commercial water taps. Accordingly, the invention will primarily be described in these contexts although it will be readily apparent to the skilled addressee that the invention has broader ramifications and may be readily modified to suit other applications. The following description is therefore not to be deemed limiting on the scope of the invention.
DESCRIPTION OF THE PRIOR ART
Common domestic water taps comprise a tap body having a fluid flow pathway extending therethrough, a valve seat located intermediate the fluid flow pathway, a tap spindle moveable towards and away from the valve seat which includes an axial recess, and a tap head which connects to the tap body and which houses the tap spindle. The tap head includes an opening in the top through which an upper portion of the tap spindle extends and on which a handle is fitted to permit the tap spindle to be rotated in the tap head and thereby move either towards or away from the valve seat.
Valves which are commonly used with this type of tap are known as tap washers or jumper valves and comprise a disc-like seal which overlies the valve seat, and a stem which extends from the disc-like seal and locates within the tap spindle. Thus, movement of the tap spindle towards the valve seat causes the disc-like seal to be brought into engagement with the valve seat to thereby stop the flow of water through the tap body.
Such disc-like seals have a number of disadvantages, prime among which are their proclivity to rapid wear, leading to a relatively limited life span. Also, it is quite common for particulate debris to be trapped on the disc so that a firm seating cannot be achieved and dripping occurs. In addition, there must be absolute tolerance between the valve seat and the valve seal otherwise it is necessary to exert significant turning pressure on the tap handle to ensure that the seal is properly sealed. This can lead to cracking of the valve seat.
One method of solving the problem of valve wear and the problem of debris entrapment is the subject of Australian Patent No. 630040. In that patent there is described a valve assembly which includes a resiliently deformable spherical sealing member on the downstream side of the valve seat. The sealing member is retained within the valve body by means of a helical spring which surrounds the spherical sealing member.
A slight drawback in the valve design described in the aforementioned Australian Patent is that in order to turn the tap off, the tap spindle must be tightly wound down to ensure that the spherical sealing member is firmly pressed against its seat. Since the sealing member is moving against the flow of fluid, this can require quite a few complete revolutions of the tap handle before the flow ceases completely.
OBJECTS OF THE INVENTION
It is therefore an object of the invention to provide an alternative valve construction which has the advantages of the aforementioned valve but addresses the drawback associated with turning the valve off, that is, by providing a simpler action requiring less turning of the valve handle.
A further object of the invention is to provide a retrofit valve which is adapted for use in conventional tap systems.
SUMMARY OF THE INVENTION
According to one aspect of the present invention there is provided a valve having a seat located in a passageway between a fluid inlet and a fluid outlet, a sealing member adapted to seal against the fluid inlet side of the seat, and a plunger for moving the sealing member off the seat.
The design of the valve is such that the pressure of the fluid is used to form the seal, thereby enabling a quick seal to be achieved. Furthermore, when the valve is incorporated into a tap body, the tap handle on the end of the plunger need only be rotated by between about one quarter and one half a turn to fully unseat the sealing member to enable full fluid flow through the valve. Also, it is impossible to damage the valve seat when closing the valve as the pressure of the fluid which enables this closure is considerably less than the force exerted by a person in winding a conventional valve shut.
The design of the valve is also such that it can be readily retrofit into an existing tap system.
DETAILED DESCRIPTION OF THE INVENTION
The sealing member preferably has a spherical configuration although other shapes are not excluded. The sealing member can be formed from a resilient material but is preferably of solid, rigid construction. Such materials of construction include stainless steel and brass, as well as natural and synthetic rubbers with appropriate additives, plastics materials, composites of these materials, and the like. It can, furthermore, be of solid or hollow construction.
It can be desirable, but not essential, that the sealing member and the inlet side of the valve seat are of complementary shape in the region where they abut one another, so as to guarantee a liquid-tight seal between the sealing member and the inlet side of the valve seat when the sealing member is in its closed position. For example, with the preferred spherical sealing member, the inlet side of the valve seat can be provided with a slightly concavely curved sealing surface extending around the flow aperture. However, as noted, this is not essential and it is typically sufficient in the majority of cases to provide a resilient seal of fabric or plastics material for the sealing member to locate onto. This will generally provide adequate sealing in the valve body.
Biasing means are preferably included in the valve design to bias the sealing member against the seat and to guide the sealing member to its sealing location. Such biasing means can comprise a spring, such as a helical compression spring, located on the fluid inlet side of the seat. The biasing means will suitably be fabricated from non-toxic, non-corrosive materials such as stainless-steel and plastics materials.
The plunger suitably extends through the valve seat from the fluid outlet side of the passageway and can be retained by, or formed integrally with, a rotatable spindle of an associated tap handle. Preferably the plunger is formed integrally with the spindle and has a reduced cylindrical configuration at the end which acts against the sealing member to unseat it and open the valve.
Another aspect of the present invention is a tap incorporating a valve as described above. The tap can be of a conventional domestic water tap or a single handle hot and cold mixing tap incorporating two of the aforementioned valve arrangements.
The tap design is such that it only takes between about ¼ and ½ a rotation of the handle to turn it fully on. Also since the action of turning on is against the flow of water and the reverse action of turning off is with the flow of water, overtightening of the tap is avoided and it is therefore essentially damage-proof. Turning off, in fact, conveys a very soft feel as such an action is assisted by the flow of water and the biasing means.
The fact that sealing is effected by means of a spherically sealing member such as a stainless steel ball or the like, means that there is very little wear at the point of sealing and the sealing member can be expected to last the life of the tap.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view of a valve according to the present invention,
FIG. 2 is a cross-sectional view of the valve of FIG. 1 in a tap body,
FIG. 3 is a cross-sectional view similar to FIG. 2 but wherein the valve is open,
FIG. 4 is a cross-sectional view of a hot and cold mixer tap incorporating two valves according to the present invention, and
FIG. 5 is an exploded perspective view of the mixer tap of FIG. 4 .
DESCRIPTION OF PREFERRED EMBODIMENT
Preferred embodiments of the invention will now be described with reference to the accompanying drawings, in which like reference numerals refer to like parts.
Referring firstly to FIG. 1 , the valve has a seat 10 located in a passageway between a fluid inlet 11 and a fluid outlet 12 .
A stainless steel spherical sealing member 13 is located on the inlet side of the seat 10 .
A cylindrical plunger 14 is located for axial movement in a housing 15 , to move the sealing element from the seat. The plunger 14 has a tapered end 16 so that it can extend through an opening in the seat 10 without significantly impeding the flow of fluid past the seat as hereinafter described. A helical groove 17 in the housing 15 accommodates a detent 18 on the plunger 14 , and regulates the axial movement of the plunger as it is rotated.
The sealing element 13 is guided to its seating position by a helical spring 20 and by virtue of the pressure of the fluid at the inlet side of the seat, as described below.
Reference is now made to FIG. 2 which shows the previously described valve fitted to a tap body 21 . The tap body can either be a body specifically made for the valve or it can be the tap body of a conventional tap which has had its original valve seating system removed.
The tap body 21 is connected to a pressurised fluid supply at 22 and has an outlet passageway at 23 .
The valve is fitted to the tap body and secured thereto by a collar 24 which is held by the housing 15 and which screws into the tap body. A washer 26 seals the bottom region of the valve to the tap body.
FIG. 3 shows the sealing member 13 displaced from its seat by the plunger 14 and the flow of fluid through the tap and valve indicated by heavy arrows.
In use, fluid flow through the tap is prevented, as shown in FIG. 2 , by the stainless steel spherical sealing element 13 seating against the seat 10 due to the pressure of the fluid on the inlet side of the valve. That is, the pressure of the fluid is used to advantage to provide the seal. Additionally, sealing can be provided by the helical spring 20 should the pressure in the system at the inlet happen to fall below that which would otherwise enable self-sealing to occur.
Rotation of the tap handle 25 by between only about one quarter to one third of a full rotation is sufficient to wind the cylindrical plunger 14 downwardly by an amount which fully unseats the sealing element 13 from the seat 10 so that it is displaced to the location shown in FIG. 3 . It will be observed that the sealing element is fully depressed into a bottom corner of the chamber in which it is located, this also being enabled by the helical spring 20 which, upon compression, acts as a guide for the sealing element to this position.
In this unseated position, fluid is free to flow through the tap in the direction shown by the arrows.
In order to turn the tap off, the handle 25 is rotated in the opposing (ie. clockwise) direction to that when it was turned on, allowing the sealing element 13 to rise under the pressure of fluid at the fluid inlet, and to be guided by the helical spring to seal against the seat 10 . Alternatively, closing could be effected automatically once the turning force on the tap handle 25 is removed. To this end, for instance, a heavier helical spring could be used instead of the normal spring 20 .
Reference is now made to FIGS. 4 and 5 which illustrate a multi-valve arrangement incorporated into a hot and cold mixer tap.
The mixer tap includes a fixed housing having a handle 30 , a rotatable spout 31 , and hot and cold water inlets 32 , 33 . Each water inlet 32 , 33 has an associated valve arrangement consisting of a stainless steel ball 34 ( 35 ) surmounted on a helical spring 54 ( 55 ), a seat 36 ( 37 ) and a plunger 38 ( 39 ) with a tapered end 40 ( 41 ) which can extend through an opening in the seat. A plurality of channel outlets, e.g. 42 , 43 are formed in the mixer tap casting which connect to the rotatable spout 31 .
The upper ends of the respective plungers 38 , 39 freely contact a floating plate 44 which is acted upon by a shaft 45 extending through a swivel control 46 . The swivel control has lugs 47 , 49 which support the control in the upper portion of the housing in such a manner that it can pivot from side to side. A sloping slot 50 is formed in the wall of the swivel control for accommodating a pin 51 , which is connected to the shaft 45 , to regulate the axial movement of the shaft 45 when it is rotated by handle 30 in a manner analogous to that described in the earlier embodiment.
In operation, fluid flow through the mixer is prevented by the stainless steel balls 34 , 35 seating against their respective seats 36 , 37 , due to the pressure of the fluid on the inlet sides of the valves.
Rotation of the handle 30 by between about one quarter to one third of a full, rotation is sufficient to drive the shaft 45 fully downward, guided by the slot 50 , and depress the floating plate 44 against the top ends of the plungers 38 , 39 . This, in turn, depresses the plungers so that their respective tapered ends pass through the valve seat openings and displace the stainless steel balls 34 , 35 from their seats, thereby enabling hot and cold water to flow in equal amounts through the valve housings, into the channel outlets, e.g. 42 , 43 and out through the spout 31 .
In order to regulate the relative flows of hot and cold water, the handle 30 is rocked toward the hot or cold water inlet side so that the swivel control 46 pivots on its lugs 47 , 49 and directs the end of the shaft 45 to one of the sides of the floating plate 44 . The floating plate then tilts and depresses either plunger 38 or 39 to a greater or lesser extent than the other. This results in the relative displacement of the stainless steel balls in their respective housings, being different so that the relative flow of hot and cold water is changed.
Halting the flow of water through the mixer can be by counter-rotation of the handle manually, or automatically as described in the previous embodiment. | A retrofit valve for primarily for use in conventional domestic, agricultural and commercial water taps. The valve has a seat ( 10 ) located in a passageway between a water inlet ( 11 ) and a water outlet ( 12 ). A spherical sealing member ( 13 ) is arranged to seal against the fluid inlet side of the seat, and a plunger ( 12 ) is provided for moving the sealing member off the seat. | 5 |
RELATED APPLICATION INFORMATION
This application is a 371 of International Application PCT/ES2012/000035 filed 17 Feb. 2012 entitled “Direct-Drive Wind Turbine”, which was on 22 Aug. 2013, with International Publication Number WO 2013/121054 A1, the content of which is incorporated herein by reference.
FIELD OF THE INVENTION
The present invention resides in the technical field of horizontal axis wind turbines and, particularly, direct drive wind turbines with a rotor directly connected to the rotor blades that turns around an internal stator.
BACKGROUND OF THE INVENTION
Wind turbines are common in the state of the art and are becoming increasingly more important for generating electrical power on a global scale. The most common wind turbines include horizontal axis wind turbines, in which a rotor hub that bears a plurality of turbine blades is attached to the internal rotor of an electric machine through a horizontal drive shaft and gearbox. The hub is mounted in a gyratory manner onto a nacelle at the top of a tower. The nacelle houses the gearbox, the electric machine and other functional elements. The gearbox, in addition to being fairly expensive, is an element that requires constant maintenance and a great deal of space, hence the dimensions of the nacelle should be sufficiently large enough to house the gearbox.
“Direct drive” wind turbines have been developed to solve this problem. A direct drive wind turbine comprises an external rotor and internal stator, a horizontal shaft connected to the external rotor so that the external rotor turns around the internal stator. It also comprises a nacelle mounted at the top of a tower that houses a shaft, carrier mechanism for bearing the horizontal shaft. The blade roots are connected to the external rotor, generally through a hollow hub. The dimensions of the hub are designed to enable access to some bolts through which the blade root is fastened directly to the hub or, where pertinent, likewise to a pitch angle adjustment mechanism to regulate the blade attack angle. The hub is an additional element that should be connected to the external rotor. The foregoing requires a relatively large unit and entails the need for additional connection elements, which should be mounted and maintained. A direct drive wind turbine of this sort is described, for instance in document WO 01/21956-A1.
Documents EP-0864748-A1, EP1394406A2, EP-1783363-A1 and DE-44155570-A1 also describe direct drive wind turbines that lack a hub with the blades directly coupled to support structures mounted equidistantly on external peripheral parts of the body of an external rotor. The problem inherent in wind turbines of this son involve the bolts employed for fastening the blade or, where pertinent, the pitch mechanism elements, to the blade support structures, since they are not accessible for inspection, maintenance or repair and/or replacement tasks. Thus, when these tasks are necessary, the entire nacelle rotor must be dismounted and lowered to the ground.
DESCRIPTION OF THE INVENTION
The present invention intends to overcome the aforementioned drawbacks in the state of the art by providing a direct drive wind turbine comprising a generator that includes an external rotor with an external annular body and internal stator; a horizontal shaft to which the external rotor is connected so that the external rotor turns around the internal stator, a nacelle mounted on top of the tower for housing a shaft carrier mechanism to bear this horizontal shaft; and a plurality of blade carrier structures evenly arranged on the outer peripheral parts of the external rotor body, with each detachable support structure coupled to a blade root of a turbine; where:
each blade root is connected to the blade carrier structure on the rotor body-through a hollow blade root extender; the blade root extender comprises a proximal end part connected to the blade carrier structure through proximal bolts, and a distal end part connected to the blade root, an inner chamber encompassed by a peripheral wall, a lateral manhole on the peripheral wall for gaining access to the inner chamber and a door to close the manhole.
The terms “proximal” and “distal” employed herein mean “near the external rotor” and “far from the external rotor”.
An extender installed between the blade root, external annular body and the side manhole will enable access to the proximal and distal bolts for inspection, maintenance, repair, tightening and/or replacement tasks in a wind turbine that is not equipped with an additional hub, rather the blades are connected to the same external annular body of the external rotor. These tasks can be executed inside the root extender's inner chamber, which provides additional safety for workers undertaking these tasks.
The direct drive wind turbine could be a conventional model in which the generator rotor comprises a plurality of permanent magnets attached internally to its external annular body and an internal stator comprising inductor windings, though it could also be a model that is electrically excited through superconductors.
Depending on the embodiment of the invention, the distal end part of the root extender is securely connected to the blade root, for instance, through distal axial bolts extending through a flange inside the root extender and penetrating into a peripheral wall of the blade root.
According to such an embodiment, each blade carrier structure could comprise a pitch system to rotate the blade consisting of a gyratory ring element that is mounted on the proximal end part of the root extender, and at least one propeller pinion driven by an electric gear motor, and engages the annular notched part of a ring element so that the root extender and, consequently, the blade turn together with the gyratory ring element. The gyratory ring element turns around a central part of the blade support structure.
The notched part could be a constituent of the outer peripheral edge of the gyratory ring element arranged underneath the proximal end part of the root extender, and could be driven by an electric gear motor attached to the external rotor body outside the root extender.
Alternatively, the notched part could be a constituent of the inner annular notched edge part of the gyratory ring element while the electric gear motor is mounted in a stationary manner at the central part of the root support structure. The proximal end part of the root extender encompasses this notched edge part, propeller pinion and electric gear motor, and turns with the gyratory ring element when the latter rotates on the blade support structure. In this case, the electric gear motor can be mounted in a stationary manner onto the central part of the blade carrier structure through a motor support so that the electric gear motor is arranged within the inner chamber of the root extender, or at least partially mounted at a gap on this central part of the blade support structure.
In another embodiment of the invention, the proximal end part of the root extender could be connected to the gyratory ring element through proximal bolts extending through an internal proximal flange on the root extender into the gyratory-ring element.
According to this alternative embodiment, each blade carrier structure could comprise a blade pitch angle adjustment mechanism to rotate the blade, consisting of a stationary ring element that is mounted on the blade support structure, and at least one propeller pinion that engages an annular notched part of the stationary ring element, and driven by an electric gear motor. The proximal end part of the root extender is mounted on a part of the support that is mounted in a gyratory manner onto blade support structure. The notched part is an inner peripheral part of the ring element located underneath the proximal edge part of the root extender. Each electric gear motor is mounted in a stationary manner on the blade carrier structure onto an inner part of the wall inside the inner chamber of the root extender. The rotation of the propeller pinion causes the electric gear motor to travel along the annular notched part inside the stationary ring element. Given that the electric gear motor is attached to the inner part of the root extender wall, it forces the root extender to move with the electric gear motor and, consequently, turn with respect of the blade support structure.
In a further embodiment, the proximal end part of the root extender is securely connected to the root support structure.
Depending on this further embodiment, the proximal end part of the extender can be securely connected to the blade carrier structure through a plurality of axial bolts extending through an inner proximal flange inside the root extender into the blade support structure.
An alternative to this further embodiment entails a blade pitch angle adjustment mechanism comprising a gyratory ring element mounted on the distal end part of the root extender. The blade pitch angle adjustment mechanism includes at least one propeller pinion that engages an annular notched part inside the gyratory ring element. The propeller pinion is driven by an electric gear motor mounted in a stationary manner on an inner distal part of the wall inside the inner chamber of the root extender. The blade root is fastened to the gyratory ring element so that the rotation of the propeller pinion causes the gyratory ring element and therefore the blade root secured thereto to rotate, hence the blade.
The present invention clearly enables access through the side manhole for inspecting, repairing and replacing the fastening bolts and other elements from inside the root extender with no need to mount an additional hub onto the external rotor; and therefore satisfactorily overcomes the drawbacks of the current state of the art.
BRIEF DESCRIPTION OF THE FIGURES
The aspects and embodiments of the invention will be described below based on some annexed schematic drawings, in which
FIG. 1 is a cross section of a first embodiment of a wind turbine according to the invention;
FIG. 2 is a cross section along line A-A marked in FIG. 1 ;
FIG. 3 is a cross section along line B-B marked in FIG. 1 ;
FIG. 4 is a cross section of a second embodiment of the invention;
FIG. 5 is a cross section along line C-C marked in FIG. 4 ;
FIG. 6 is a partial cross section of a blade carrier structure and root extender-according to a third embodiment of the invention;
FIG. 7 is a cross section along line D-D marked in FIG. 6 ;
FIG. 8 is a partial cross section of a blade carrier structure and root extender according to a fourth embodiment of the invention;
FIG. 9 is a cross section along line E-E marked in FIG. 8 ;
FIG. 10 is a partial cross section of a blade carrier structure and root extender-according to a fifth embodiment of the invention;
FIG. 11 is a cross section along line F-F marked in FIG. 10 ;
FIG. 12 is a partial cross section of a blade carrier structure and root extender according to a sixth embodiment of the invention;
FIG. 13 is a cross section along line G-G marked in FIG. 12 .
These figures contain numbered references for identifying the following elements
1 external rotor 1 a external body ring 1 b front shield 1 c rear shield 1 d front bearing 1 e rear bearing 2 permanent magnets 3 internal stator 4 internal coils 5 horizontal axis/shaft 6 nacelle 6 a nose 7 tower 8 axis/shaft support mechanism 9 blade support structure 9 a central part 9 b peripheral support part/area 10 turbine blade 10 a blade root 11 a proximal axial pins 11 b , 11 c distal axial pins 12 root extensor 12 a proximal extreme part 12 b proximal flange 12 c distal extreme part 12 d distal flange 12 e internal chamber 12 f peripheral wall 13 lateral entry 14 door 15 , 15 i ring element 15 a serrated part 15 b connecting part 15 c lowered part 16 driving pinion 17 electrical geared motor 18 counterweight 19 proximal bearing 20 distal bearing 21 motor/engine support 22 external fairing 23 ring element support part
EMBODIMENTS OF THE INVENTION
In the embodiment illustrated in FIGS. 1 through 3 , the direct drive wind turbine comprises a nacelle - 6 - mounted at the top of a tower - 7 -, an external rotor - 1 - having an external annular body - 1 a - with a plurality of permanent magnets - 2 - fastened inside the external annular body - 1 a -, and an internal stator - 3 - comprising inductor windings - 4 -.
The external rotor - 1 - comprises a front shield - 1 b - and a rear shield - 1 c - connected to a horizontal shaft - 5 - respectively through a front bearing - 1 d - and a rear bearing - 1 e - so that the external rotor - 1 - can rotate around the internal stator - 3 -. The horizontal shaft - 5 - is supported by a conventional shaft carrier mechanism - 8 - housed in the nacelle. Counterweights - 18 - are arranged at the rear part of the nacelle. A cone nose - 6 a - is mounted at the forward part of the external rotor - 1 -.
The peripheral parts of the external rotor body - 1 a - of the external rotor - 1 - are equipped with three evenly distributed blade carrier structures - 9 - arranged to connect a blade root - 10 a - of a wind turbine blade - 10 -. Each blade root - 10 a - is connected to one of the blade carrier structures - 9 - on the external annular body - 1 a - by a hollow blade extender - 12 - that comprises an inner chamber - 12 e - encompassed by a peripheral wall - 12 f -, a proximal end part - 12 a - securely connected to the blade carrier structure - 9 - by proximal bolts - 11 a - and a distal end part - 12 c - securely connected to the blade root by distal bolts - 11 b -. The peripheral wall has a side manhole - 13 - to gain access to the inner chamber - 12 e -. The manhole - 13 - is closed by a door - 14 -.
The proximal end part - 12 a - of the root extender - 12 - is securely connected to the blade carrier structure - 9 - through a plurality of proximal axial bolts - 11 a - that extend through an internal proximal flange - 12 b - mounted on the root extender - 12 - toward the inner part of the blade carrier structure - 12 -, while the distal end part - 12 c - of the root extender - 12 - is securely connected to the blade root - 10 a - through distal axial bolts - 11 b , 11 c - that extend through an internal distal flange - 12 d - mounted on the root extender - 12 - and penetrate a peripheral wall on the blade root - 10 a -. Thus, the bolts - 11 a , 11 b - can be accessed from the inner chamber - 12 e - of the root extender - 12 -.
The second embodiment of the direct drive wind turbine illustrated in FIGS. 4 and 5 differs from the first embodiment illustrated in FIGS. 1 through 3 in that each root extender - 12 - is connected respectively to one of the blade carrier structures - 9 - through a pitch angle adjustment mechanism for rotating the blade - 10 -. The blade pitch angle adjustment mechanism comprises a gyratory ring element - 15 - mounted in a gyratory manner onto the proximal end part - 12 a - of the root extender - 12 - so that the blade - 10 - rotates with the gyratory ring element - 15 -, a propeller pinion - 16 - that engages an annular notched edge part - 15 a - inside the gyratory ring element - 15 - and bearings - 19 that enable the gyratory ring element - 15 - to turn on the support structure - 9 -.
The gyratory pinion - 16 - is driven by an electric gear motor - 17 - mounted stationary on a central part - 9 a - of a blade carrier structure - 9 - through a motor support - 21 - so that the root extender - 12 - and, therefore, the blade - 10 - rotate with the gyratory ring element - 15 -.
The proximal end part - 12 a - of the root extender - 12 - is mounted on the ring element - 15 - through proximal bolts - 11 a - extending through a proximal flange - 12 b - on the root extender - 12 -, so that the proximal end part - 12 a - of the root extender - 12 - encompasses the notched edge part - 15 a -, the propeller pinion - 16 - and the electric gear motor - 17 -. Thus, the proximal bolts - 11 a -, distal bolts - 11 b -, the notched edge part - 15 a -, propeller pinion - 16 - and the electric gear motor - 17 - are housed and accessible from the inner chamber - 12 e - of the root extender - 12 -.
In the third embodiment illustrated in FIGS. 6 and 7 , each blade pitch angle adjustment mechanism comprises a ring element - 15 - mounted in a gyratory manner at the central part - 9 a - of the blade carrier structure - 9 - through bearings - 19 -. The root extender - 12 - is securely mounted on the ring element - 15 - through proximal bolts - 11 a - extending through a proximal flange - 12 b - on the proximal end part - 12 a - of the root extender - 12 - so that the root extender - 12 - and blade - 10 - turn together with the gyratory ring element - 15 -. The distal end part - 12 b - of the root extender - 12 - is mounted on the blade root - 10 a - as illustrated in FIGS. 1 through 3 . Thus, the proximal bolts - 11 a - and distal bolts - 11 b - are housed and accessible from the inner chamber - 12 e - of the root extender - 12 -.
The ring element - 15 - comprises an outer notched part - 15 a -, which is part of an outer peripheral edge of the gyratory ring element - 15 - located underneath the proximal edge part - 12 a - of the root extender - 12 -. The gyratory ring element - 15 - is driven by a propeller pinion - 16 - of an electric gear motor - 17 - that is fastened to the external annular body - 1 a - outside the root extender - 12 -.
In the fourth embodiment illustrated in FIGS. 8 and 9 , each blade pitch angle adjustment mechanism comprises a ring element - 15 - mounted in a gyratory manner at the central part - 9 a - of the blade carrier structure - 9 - through bearings - 19 -. The root extender - 12 - is securely mounted on the ring element - 15 - through proximal bolts - 11 a - extending through a proximal flange - 12 b - on the proximal end part - 12 a - of the root extender - 12 - so that the root extender - 12 - and blade - 10 - turn together with the gyratory ring element - 15 -. The distal end part - 12 b - of the root extender - 12 - is mounted on the blade root - 10 a - in the same manner as illustrated in FIGS. 1 through 3 .
The root extender - 12 - is securely mounted on the ring element - 15 - through proximal bolts - 11 a - extending through a proximal flange - 12 b - on the proximal end part - 12 a - of the root extender - 12 - so that the root extender - 12 - and blade - 10 - turn together with the gyratory ring element - 15 -. The distal end part - 12 b - of the root extender - 12 - is mounted on the blade root - 10 a - in the same manner as illustrated in FIGS. 1 through 3 .
The gyratory ring element - 15 - comprises an internal notched part - 15 a -, which is a constituent of the inner peripheral edge of the gyratory ring element - 15 - driven by the propeller pinion - 16 - of an electric gear motor - 17 - that is mounted at least partially in a stationary manner at a gap on this central part of the blade carrier structure - 9 -. Thus, the proximal bolts - 11 a -, distal bolts - 11 b -, the notched edge part - 15 a -, propeller pinion - 16 - and the electric gear motor - 17 - are housed and accessible from the inner chamber - 12 e - of the root extender - 12 -.
In the fifth embodiment illustrated in FIGS. 10 and 11 , the distal end part - 12 b - of the root extender - 12 - is also mounted on the blade root - 10 a - as illustrated in FIGS. 1 through 3 . A blade pitch angle adjustment mechanism for turning each blade is envisioned. The proximal mechanism for adjusting the blade pitch angle comprises a stationary ring element - 15 ′- mounted in a stationary manner on the blade carrier structure - 9 - through fastening bolts (not shown) or otherwise, and a propeller pinion - 16 - driven by an electric gear motor - 17 - that engages an annular notched part - 15 a - inside the ring element - 15 - that is stationary - 15 ′-. The electric gear motor - 17 - is mounted in a stationary manner next to the blade carrier structure - 9 - onto an inner part of the wall inside the inner chamber - 12 e - of the root extender - 12 -. The proximal end part - 12 a - of the root extender - 12 - is mounted on a peripheral support part - 9 b -, which is mounted in a gyratory manner on the blade carrier structure - 9 - through proximal bolts - 11 a - that extend through an internal proximal flange - 12 b - on the root extender - 12 - into the peripheral support part - 9 b -. Thus, the proximal bolts - 11 a -, distal bolts - 11 b -, the notched edge part - 15 a -, propeller pinion - 16 - and the electric gear motor - 17 - are housed and accessible from the inner chamber - 12 e - of the root extender - 12 -.
According to this fifth embodiment, the rotation of the propeller pinion - 16 - causes the electric gear motor - 17 - to travel along the annular notched part - 15 a - inside the stationary ring element - 15 -. Given that the electric gear motor - 17 - is attached to the inner part of the root extender wall - 12 -, it forces the root extender - 12 - to move with the electric gear motor - 17 - and, consequently, turn with respect of the blade carrier structure - 9 -.
In the sixth embodiment illustrated in FIGS. 12 and 13 , the proximal end part - 12 a - of the root extender - 12 - is mounted on the blade carrier structure - 9 - as illustrated in FIGS. 1 through 3 . Mounted in a gyratory manner on the distal end part - 12 b - at the root, extender - 12 -, there is a blade pitch angle adjustment mechanism for each blade, comprising a gyratory ring element - 15 -. The distal mechanism for adjusting the blade pitch angle includes at least one propeller pinion - 16 - that engages an annular notched part - 15 a - inside the gyratory ring element - 15 -. The propeller pinion - 16 - is driven by an electric gear motor - 17 - mounted in a stationary manner on an inner distal part of the wall inside the inner chamber - 12 e - of the root extender - 12 -. The blade root - 10 a - is fastened to the gyratory ring element - 15 - so that the rotation of the propeller pinion - 16 - causes the gyratory ring element - 15 - in addition to the blade root - 10 a - and blade - 10 - secured thereto to rotate. As illustrated, the proximal bolts - 11 a -, distal bolts - 11 b -, the notched edge part - 15 a -, propeller pinion - 16 - and the electric gear motor - 17 - are housed and accessible from the inner chamber - 12 e - of the root extender. | A direct-drive wind turbine comprising an external rotor having an external anular body and a stator, a nacelle which is mounted on an upper part of a tower and which houses a shaft-holder mechanism for supporting the horizontal shaft, a plurality of blade-holder structures arranged equidistantly on external peripheral portions of the external anular body, and a blade root connected to the blade-holder structure, said turbine also including a distal end part connected to the blade root, a lateral hatch for accessing an internal chamber in the blade ender and a door for closing the hatch. | 5 |
BACKGROUND
The invention relates to a device for the variable adjustment of the control times for gas-exchange valves of an internal combustion engine according to the preambles of claims 1 or 5 .
In internal combustion engines, camshafts are used for actuating the gas-exchange valves. Camshafts are mounted in the internal combustion engine such that cams mounted on the camshafts contact cam followers, for example, cup tappets, finger levers, or rocker arms. If a camshaft is set in rotation, then the cams roll against the cam followers, which, in turn, actuate the gas-exchange valves. Through the position and the shape of the cams, both the opening period and also the opening amplitude, but also the opening and closing times of the gas-exchange valves are set.
Modern engine concepts are moving towards a design with a variable valve drive. On one hand, the valve stroke and valve opening period should be able to be shaped variably up to the complete shutdown of an individual cylinder. For this purpose, concepts, such as switchable cam followers or electro-hydraulic or electrical valve actuators are provided. Furthermore, it has been shown to be advantageous to influence the opening and closing times of the gas-exchange valves during the operation of the internal combustion engine. Here, it is especially desirable to influence the opening or closing times of the intake or exhaust valves separately, in order to selectively set, for example, a defined valve overlap. By adjusting the opening or closing times of the gas-exchange valves as a function of the current engine-map range, for example, the current rotational speed or the current load, the specific fuel consumption can be reduced, the exhaust-gas behavior can be positively influenced, and the engine efficiency, the maximum torque, and the maximum output can be increased.
The described variability of the valve control times is achieved through a relative change in the phase position of the camshaft relative to the crankshaft. Here, the camshaft is usually in driven connection with the crankshaft via a chain, belt, or gear drive or a driving concept with an identical function. Between the chain, belt, or gear drive driven by the crankshaft and the camshaft there is a device for changing the control times of an internal combustion engine, also called camshaft adjuster below, which transfers the torque from the crankshaft to the camshaft. Here, this device is constructed so that during the operation of the internal combustion engine, the phase position between the crankshaft and the camshaft can be held securely and, if desired, the camshaft can be rotated within a certain angular range relative to the crankshaft.
Belt-driven camshaft adjusters are usually arranged outside of the cylinder head. Here, care must be taken that the camshaft adjuster must be completely sealed from the surroundings, in order to prevent the leakage of motor oil into the engine compartment. Any leakage oil must be captured and led back into the cylinder head.
In internal combustion engines with separate camshafts for the intake valves and the exhaust valves, these can each be equipped with a camshaft adjuster. Therefore, the opening and closing times of the intake and exhaust valves can be shifted in time relative to each other and the valve overlap can be adjusted selectively.
The position of modern camshaft adjusters is usually located on the driving-side end of the camshaft. The camshaft adjuster, however, can also be arranged on an intermediate shaft, a non-rotating component, or the crankshaft. It is made from a drive wheel, which is driven by the crankshaft and which keeps a fixed phase relationship relative to this crankshaft, a driven part in driving connection with the camshaft, and an adjustment mechanism transferring the torque from the drive wheel to the driven part. The drive wheel can be constructed, in the case of a camshaft adjuster not arranged on the crankshaft, as a chain, belt, or gear and is driven by the crankshaft by a chain, belt, or gear drive. The adjustment mechanism can be operated electrically (by a driving triple-shaft gear mechanism), hydraulically, or pneumatically.
A preferred embodiment of the hydraulic camshaft adjuster is the so-called rotary piston adjuster. In this embodiment, the drive wheel is locked in rotation with a stator. The stator and a driven element are arranged concentric to each other, wherein the driven element is connected non-positive, positive, or form fit, for example, by a press fit, a screw connection, or a weld connection, to the camshaft, an extension of the camshaft, or an intermediate shaft. In the stator, several hollow spaces spaced apart in the circumferential direction are formed, which extend radially outward from the driven element. The hollow spaces are defined in a pressure-tight way by side covers in the axial direction. Into each of these hollow spaces extends a blade, which is connected to the driven element and which divides each hollow space into two pressure chambers. Through selective connection of the individual pressure chambers to a pressurized medium pump or to a tank, the phase of the camshaft can be adjusted or held relative to the crankshaft.
For controlling the camshaft adjuster, sensors detect the characteristic data of the engine, such as, for example, the load state and the rotational speed. This data is fed to an electronic control unit, which controls the inflow and outflow of pressurized medium to and from the different pressure chambers after comparing the data with a characteristic data map of the internal combustion engine.
To adjust the phase position of the camshaft relative to the crankshaft, in hydraulic camshaft adjusters, one of the two pressure chambers of a hollow space acting against each other is connected to a pressurized medium pump and the other is connected to the tank. In this way, the pressurization of one chamber and the release of pressure in the other chamber displace the blade and thus directly cause a rotation of the camshaft relative to the crankshaft. To keep the phase position, both pressure chambers are either connected to the pressurized medium pump or both are separated from the pressurized medium pump and also the tank.
The pressurized medium flows to or from the pressure chambers are controlled by a control valve, usually a 4/3 proportional valve. Each valve housing is provided with a connection for the pressure chambers (working connection), a connection to the pressurized medium pump, and at least one connection to a tank. Within the essentially hollow cylindrical valve housing there is a control piston that can be shifted in the axial direction. The control piston can be brought into each position between two defined end positions in the axial direction via an electromagnetic actuator against the spring force of a spring element. The control piston is further provided with annular grooves and control edges, whereby the individual pressure chambers can be connected selectively to the pressurized medium pump or to the tank. Likewise, a position of the control piston can be provided, in which the pressure chambers are separated both from the pressurized medium pump and also from the pressurized medium tank.
Such a device is disclosed in DE 199 08 934 A1. This involves a device with a rotary piston construction. A stator is supported so that it can rotate on a driven element locked in rotation with a camshaft. The stator is constructed with recesses open to the driven element. In the axial direction of the device, compensating disks are provided, which define the recesses in the axial direction in a sealing manner. The recesses are closed in a pressure-tight manner by the stator, the driven element, and the compensating disks and thus form pressure spaces. On the outer casing surface of the driven element there are blades, which extend into the recesses. The blades are constructed so that they divide the pressure chambers into two pressure chambers acting against each other. By supplying or discharging pressurized medium to or from the pressure chambers, the phase position of the driven element can be selectively maintained or adjusted relative to the stator and thus the camshaft relative to the crankshaft. For this purpose, a device for the pressurized medium supply is provided with pressurized medium lines and a control valve.
The stator, the driven element, and the compensating disks are encapsulated by a two-part housing, which is locked in rotation with a drive wheel constructed as a toothed belt wheel.
The flat bases of the housing halves ensure a pressure-tight contact of the compensating disks on the stator and the driven element.
In addition, the driving torque of the crankshaft is transferred to the stator with a friction fit via the drive wheel and the bases of the compensating disks. Alternatively, it is proposed that the side surfaces of the stator have profiling, whereby an additional positive fit can be achieved.
In this embodiment, a large number of components are required for realizing the device, whereby increased assembly costs and thus production costs occur. In addition, the described transmission of the torque from the drive wheel to the stator is associated with increased production expense, which has a negative effect on the costs of the device.
SUMMARY
Therefore, the invention is based on the objective of avoiding these mentioned disadvantages and thus providing a device for the variable adjustment of the control times of gas-exchange valves of an internal combustion engine, in which the number of components and thus the assembly expense and the production costs of the device are reduced. Furthermore, the device shall be improved to the extent that the transfer of the torque from the crankshaft to the stator is improved and is achieved with more cost-effective measures.
In a first embodiment of a device for the variable adjustment of the control times of gas-exchange valves of an internal combustion engine with a stator, a driven element arranged coaxial thereto, wherein the two components are mounted so that they can rotate relative to each other and wherein the two components define at least one pressure space at least in the radial direction and in the circumferential direction, and with a housing, which is constructed separate from the stator and from the driven element and which at least partially encapsulates the stator and the driven element, the objective is met according to the invention in that the housing defines the pressure space in an axial direction in a sealing manner.
Here, it can be provided that the housing is made from at least two housing elements and at least one flat section of the housing projecting perpendicular to the axial direction of the device acts as a sealing surface for the pressure space and defines this space in an axial direction.
In one refinement of the invention, it is provided that the housing defines the pressure space in a sealing manner also in the other axial direction.
In addition, it can be provided that the stator is in driving connection with the housing via a positive-fit connection.
In another embodiment of a device for the variable adjustment of the control times of gas-exchange valves of an internal combustion engine with a driven element driving a camshaft, a stator driven by a crankshaft, wherein the two components are mounted so that they can rotate relative to each other, and with a housing, which is constructed separate from the stator and from the driven element and which at least partially encloses these components, wherein at least one pressure chamber is defined by the stator, the driven element, and the housing, the objective according to the invention is met in that a base of a pot-shaped section of the housing acts as a sealing surface for the pressure space at least in one axial direction.
In all of the embodiments, the stator can be constructed as a sheet-metal part that is shaped without cutting or as a solid sintered component.
In the case of the construction of the stator as a sheet-metal part shaped without cutting, this can be produced by a deep-drawing process.
It is also conceivable to construct at least one housing element as a sheet-metal part shaped without cutting, wherein this part can be produced by a deep-drawing process.
Such devices can be provided with a chain, a belt, or a gear and can be in drive connection with the crankshaft via a chain, a toothed belt, or a gear drive.
If the device is to be driven by means of a toothed belt, then the housing is constructed so that this prevents the discharge of pressurized medium from the device.
The two housing elements can be connected to each other by a weld connection, whereby the housing prevents the discharge of pressurized medium from the device.
In one advantageous refinement of the invention, it can be provided that a cylindrical section extending in the axial direction is constructed on the housing for sealing the device against a radial shaft sealing ring. In addition, it can be provided that a camshaft engages in the section and that a gap is constructed between the inner diameter of the section and the camshaft. Therefore, the device can be arranged outside of the cylinder head, wherein the section engages in an opening of the cylinder head and is sealed to this cylinder head by the radial shaft seal. Any leakage oil can be fed back via the gap between the section and the camshaft into the cylinder head and thus into the crankcase.
In another advantageous refinement of the invention, it is provided that molded elements are constructed on at least one of the housing elements for increasing the surface area. These molded elements are used, first, for reinforcing the housing and, second, for increasing its surface area, which leads to better cooling of the device. The molded elements can be constructed, for example, as cooling ribs.
By encapsulating the stator and the driven element by a housing, among other things, the following two tasks are fulfilled. First, the housing is used for closing the pressure spaces in the axial direction of the device in a pressure-tight manner. This can be realized either indirectly by pressing sealing disks against the stator or directly by the formation of sealing surfaces on the housing. In the case of toothed belt-driven devices, which are usually arranged outside of the cylinder head, the housing is also used as encapsulation for the device, which prevents the discharge of pressurized medium from the device into the engine compartment. Any leakage oil is captured within the housing and fed back into the engine compartment via an axial section. In this embodiment, the driven element is usually constructed as a sintered component, which must be sealed in a processing step following the shaping process. This processing step is usually very time-intensive and thus cost-intensive.
Through the formation of the housing as a sheet-metal part shaped without cutting, which is naturally oil-tight, such sealing processing steps can be eliminated. In addition, the number of connection points to be sealed can be reduced from at least two (between the side covers and the stator) to one (between the housing halves).
In comparison with the device described in the state of the art, a cost advantage can be achieved in that at least the function of one of the sealing disks is integrated into the housing. For this purpose, at least one base of a pot-shaped section of the housing has a flat construction. This base lies in a pressure-tight way in the axial direction both on the stator and also on the driven element.
The housing is made from two housing elements, in which the stator and the driven element can be placed. Here, both housing elements can have a pot-shaped construction. Also conceivable is an embodiment with a pot-shaped housing element and a flat housing element. The housing elements can be connected to each other by connection means, for example, screws or bolts, or a non-positive or positive fit. The base of at least one of the pot-shaped sections is flat and constructed so that it bounds the pressure spaces constructed between the stator and the driven element in an axial direction in a pressure-tight manner. It is also conceivable that the pressure spaces are defined in both axial directions by flat sections of the housing that are perpendicular to the axial direction of the device.
By reducing the number of components and the associated lower assembly expense, the costs of the device can be reduced considerably. Here, the cost-effective production of the housing elements has a positive effect through a non-cutting shaping process, for example, a deep-drawing process.
Also conceivable is the use of a stator, which is produced in a non-cutting shaping process from a sheet-metal blank. By forming the stator as a thin-walled, shaped sheet-metal part, in the circumferential direction of the stator, radial profiling is constructed. In this case, the stator is made from radially outer circumferential walls and radially inner circumferential walls and side walls, which each connect an inner circumferential wall to an outer circumferential wall. This profiling can be used to transfer the torque transmitted from the drive wheel to the housing to the stator. For this purpose, the inner diameter of the circumferential surface of the pot-shaped section or sections is adapted to the outer diameter of the outer circumferential walls. Consequently, the stator can be held in the housing, wherein the stator is simultaneously centered relative to the housing. Between the outer circumferential walls of the stator, on the pot-shaped section/s of the housing housing/s there are formations, which are constructed so that they contact corresponding side walls. In this way, in the circumferential direction a positive-fit connection is realized, by which the torque can be transferred from the housing to the stator. By transmitting the torque via surfaces in contact in the circumferential direction and the enlarged contact surface area, the stator can be made thinner and thus more lightweight and more cost-effective. In addition, this type of connection can be produced significantly more reliably.
In addition, the formations in the housing can be used for the engagement of the drive wheel. By forming an inner casing surface of the drive wheel complementary to the outer casing surface of the housing, at this point a positive-fit connection in the circumferential direction can also be produced.
Likewise, the use of this positive-fit connection between the housing and a solid stator, for example, made from sintered metal, is also conceivable. Advantageously, for this purpose, the profiling of the outer circumferential surface of the stator is already taken into account in the shaping tool. Therefore, no additional costs are generated, while the quality of the stator-housing connection can be significantly improved.
Naturally, the invention is also conceivable in chain-driven or gear-driven devices.
In one advantageous refinement of the invention, a locking device is provided, wherein a locking pin engages in a connecting element formed on a sealing disk and wherein the sealing disk is made from steel that can be hardened.
BRIEF DESCRIPTION OF THE DRAWINGS
Additional features of the invention emerge from the following description and from the drawings, in which embodiments of the invention are shown simplified. Shown are:
FIG. 1 a a simplified schematic view of an internal combustion engine,
FIG. 1 a longitudinal section view through a device according to the invention,
FIG. 2 a plan view of the device according to the invention from FIG. 1 along the line II-II,
FIG. 3 a perspective view of a housing element of the device according to the invention from FIG. 1 ,
FIG. 4 a plan view of the other device according to the invention analogous to that from FIG. 1 , along the line II-II.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
In FIG. 1 a , an internal combustion engine 100 is sketched, wherein a piston 102 sitting on a crankshaft 101 is shown in a cylinder 103 . The crankshaft 101 connects in the shown embodiment via a traction mechanism drive 104 or 105 with an intake camshaft 106 or an exhaust camshaft 107 , wherein a first and a second device 1 can provide for a relative rotation between the crankshaft 101 and camshafts 106 , 107 . Cams 108 , 109 of the camshafts 106 , 107 actuate an intake gas-exchange valve 110 or the exhaust gas-exchange valve 111 . Likewise, it can be provided to equip only one of the camshafts 106 , 107 with a device 1 or to provide only one camshaft 106 , 107 , which is provided with a device 1 .
FIGS. 1 and 2 show a first embodiment of a device 1 for variable adjustment of the control times of gas-exchange valves of an internal combustion engine. Below, the invention will be explained with reference to a belt-driven device 1 . Also conceivable are chain-driven or gear-driven devices. The special feature of the belt-driven devices lies in their pressurized medium-tight encapsulation, which is not necessary in the other embodiments. A control device 1 a is comprised essentially from a stator 2 and a driven element 3 arranged concentric to the stator. In FIG. 2 , a plan view of a sealing disk 12 is shown, wherein components lying behind this disk are indicated by dashed lines.
The driven element 3 is made from a wheel hub 4 , on whose outer periphery axial blade grooves 5 are formed, and five blades 6 , which are arranged in the blade grooves 5 , extend radially outwardly. Furthermore, the driven element 3 is provided with a stepped central borehole 4 a , in which a not-shown camshaft engages, in FIG. 1 from the right, in the assembled state of the device 1 . In the assembled state of the device 1 , this is locked in rotation with the camshaft, for example, by a non-positive fit, friction fit, positive fit, or press fit connection or by fastening means.
The stator 2 is constructed as a thin-walled sheet-metal part, wherein this is made from inner circumferential walls 7 and outer circumferential walls 8 , which are connected to each other via side walls 9 . The inner and outer circumferential walls 7 , 8 extend essentially in the circumferential direction, while the side walls 9 extend essentially in the radial direction. The stator 2 is produced in one part by a non-cutting shaping process from a sheet-metal blank. Here, it can be provided to produce the stator 2 by a deep-drawing method, for example, from a steel plate, without cutting. Through the use of the inner circumferential walls 7 , which contact a cylindrical circumferential wall of the driven element 3 , the stator 2 is supported so that it can rotate on the driven element 3 . Starting from the inner circumferential walls 7 , the side walls 9 extend essentially in the radial direction outward and transition into the outer circumferential walls 8 . Through this construction, several pressure spaces 10 are formed, in the shown embodiment five, which, as described below, are closed in a pressure-tight manner in the axial direction by a housing 11 or by a sealing disk 12 .
The blades 6 are arranged on the outer casing surface of the driven element 3 such that a blade 6 extends into a pressure space 10 . Here, the blades 6 contact the outer circumferential walls 8 of the stator 2 in the radial direction. For this purpose, spring elements 13 , which force the blades 6 radially outwardly, are arranged in the blade grooves 5 . The width of the blades 6 is constructed so that the blades 6 contact the housing 11 or the sealing disk 12 in the axial direction. In this way, it is achieved that each blade 6 divides a pressure space 10 into two pressure chambers 14 , 15 acting against each other.
The stator 2 and the driven element 3 are arranged within the housing 11 , which is constructed so that it encapsulates these components in an oil-tight manner. The housing 11 is made from an essentially pot-shaped first housing element 16 and a disk-shaped second housing element 17 . The connection point of the housing elements 16 , 17 can be sealed by a not-shown sealing means or by a sealing joining method. In the shown embodiment, a weld connection 16 a in the circumferential direction is provided. The first housing element 16 is arranged on the camshaft-facing side of the device 1 . A flat section perpendicular to the axial direction of the device 1 in a pot-shaped section of the first housing element 16 , called base 18 below, is put through symmetric to the rotational axis of the first housing element 16 , wherein a cylindrical section 19 extending in the axial direction is formed. The section 19 is used, first, for holding the not-shown camshaft or a pressurized medium distributor. Second, in the case of a belt-driven device 1 , the outer casing surface of the cylindrical section 19 can be used as a seat of a radial shaft seal 20 , which seals the device 1 relative to a not-shown cylinder head.
The inner diameter of the essentially cylindrical casing surface of the pot-shaped section of the first housing element 16 is adapted to the outer diameter of the outer circumferential walls 8 of the stator 2 . This guarantees a centered holding of the stator 2 in the first housing element 16 . In addition, the essentially cylindrical casing surface of the first housing element 16 is provided with formations 21 , which extend radially inward between adjacent outer circumferential walls 8 of the stator 2 . The formations 21 are constructed such that these contact the corresponding two side walls 9 of the stator 2 in the circumferential direction. In this way, a positive-fit connection is produced in the circumferential direction between the stator 2 and the housing 11 , whereby the two components are locked with each other in rotation. Here it can be provided that the formations 21 extend up to the inner circumferential walls 7 of the stator 2 or that the formations 21 engage only partially in this hollow space.
In addition, a radially extending collar 22 , in which boreholes 23 are formed, is constructed on the end of the first housing element 16 facing away from the camshaft.
The second housing element 17 is arranged coaxial to the first housing element 16 , wherein the outer circumferential surface of the second housing element 17 is constructed complementary to the collar 22 of the first housing element 16 . Through the use of connection means 24 , screws in the shown embodiment, the two housing elements 16 , 17 and a drive wheel 24 constructed as a belt wheel are locked in rotation with each other. Alternatively, non-positive or positive-fit connection methods could also be provided. In addition, the inner circumferential surface of the drive wheel 24 could be constructed complementary to the outer circumferential surface of the first housing element 16 , whereby the drive wheel 24 engages in the formations 21 of the first housing element 16 and thus the two components are connected with a positive fit in the circumferential direction. The introduction of the torque transmitted from the crankshaft to the drive wheel 24 can now be transmitted to the stator via the positive-fit connections between the drive wheel 24 and the formations 21 of the first housing element 16 and furthermore via the positive-fit connections between the formations 21 and the stator 2 . This positive-fit connection of the components in the circumferential direction replaces the friction-fit connection described in the state of the art between the bases of the housing elements and an axial side surface of the stator 2 . Thus, the transmitted forces act in the direction of the connection between the components and over a significantly larger surface, whereby the forces can be transmitted reliably. The transmitted force is distributed onto a larger connection surface, whereby the stator 2 can have a thin-walled construction. In this way, in addition to the functional reliability of the torque transmission, the weight of the device 1 and thus its moment of inertia and also the costs will be reduced.
The second housing element 17 can be provided, as shown in FIG. 1 , with a central opening 17 a . This opening 17 a is used for an embodiment of the device 1 , in which the driven element 3 is fixed by a central screw to the camshaft, as an engagement opening for a tool for tightening the central screw. In this case, the opening 17 a can be closed in an oil-tight manner by a not-shown cover after the assembly of the device 1 on the camshaft.
Also conceivable are embodiments of the device 1 , in which the second housing element 17 is constructed without an opening 17 a.
On the second housing element 17 , molded elements 11 a are formed, which, first, cause a reinforcement of the component and, second, increase the surface area of the housing 11 and thus contribute to improved cooling. Especially advantageous is a construction of the molded elements 11 a as cooling ribs. In FIG. 3 , a perspective view of the first housing element 16 is shown. The formations 21 , which engage inwardly in the radial direction into the hollow spaces of the stator 2 , can be seen easily. The formations 21 also allow the engagement of the drive wheel 24 on the outer casing surface, wherein advantageously the inner casing surface of the drive wheel 24 is adapted to the outer casing surface of the first housing element 16 .
As is to be seen in FIG. 1 , the pressure spaces 10 are closed pressure-tight in the axial direction on the camshaft-facing side of the device 1 by the base 18 of the first housing element 16 . For this purpose, the base 18 of the first housing element 16 has a flat construction and is arranged such that it connects in the axial direction directly to the driven element 3 or the stator 2 . On the side of the device 1 facing away from the camshaft, there is a sealing disk 12 between the second housing element 17 and the stator 2 or the driven element 3 . The outer periphery of the sealing disk 12 is adapted to the inner contours of the first housing element 16 , whereby it is locked in rotation with the housing 11 and thus with the stator 2 . This contacts both the driven element 3 and also the stator 2 , at least in the region of the pressure spaces, and is pressed by the second housing element 17 against the stator 2 , whereby the pressure spaces 10 are closed pressure-tight in this axial direction. Alternatively, it is also conceivable to eliminate this sealing disk 12 and to implement the axial sealing of the pressure spaces 10 by the second housing element 17 . For this purpose, this second housing element 17 also must have a flat construction.
Therefore, because the base 18 of the first housing element 16 is used as a sealing surface for the pressure spaces 10 in the axial direction, a second sealing disk can be eliminated, whereby the number of components and thus the assembly expense and the costs of the device 1 can be reduced. These advantages could be increased in that the sealing disk 12 is also eliminated and the sealing of the pressure spaces is also implemented in this axial direction by the second housing element 17 .
The device 1 is further provided with two groups of pressurized medium lines 25 , 26 , which extend outward starting from the central borehole 4 a of the driven element 3 in the radial direction. The first pressurized medium lines 25 here open into the first pressure chambers 14 , while the second pressurized medium lines 26 open into the second pressure chambers 15 . Through the use of a pressurized medium distributor or alternatively a control valve arranged in the central borehole 4 a of the driven element 3 , pressurized medium can be selectively fed or led away from the first or the second pressure chambers 14 , 15 via the pressurized medium lines 25 , 26 . Thus, between the first and second pressure chambers 14 , 15 a pressure gradient can be established. Whereby the blades 6 are forced in the circumferential direction and thus the relative phase position of the driven element 3 relative to the stator 2 can be selectively adjusted variably or held. By adjusting the phase position between the driven element 3 , which is locked in rotation with the camshaft and the stator 2 , which is in driven connection with the crankshaft, the phase position between the crankshaft and camshaft can be selectively influenced and thus the control times of the gas-exchange valves relative to the position of the crankshaft can be influenced.
In addition, in FIG. 2 , a rotational angle limiting device 27 is shown, which is realized by a pin 28 locked in rotation with the driven element 3 and a recess 29 constructed on the sealing disk 12 . The pin 28 engages in the recess 29 , wherein the recess 29 extends in the circumferential direction, such that the pin 28 comes to lie in both extreme positions of the driven element 3 relative to the stator against an essentially radial wall of the recess 29 . In this way it is prevented that the blades 6 extend into the transition region between the outer circumferential walls 8 and the side walls 9 . Thus, it is prevented that the blades 6 are fixed at the radii constructed there.
For an insufficient supply of pressurized medium to the device 1 , for example, during the start-up phase of the internal combustion engine or while idling, the driven element 3 is moved in an uncontrolled way relative to the stator 2 due to the changing and towing moments, which the camshaft exerts on this driven element. In a first phase, the towing moments of the camshaft force the driven element 3 relative to the stator 2 in a circumferential direction, which lies opposite the rotational direction of the stator 2 , until this movement is stopped by the rotational angle limiting device 27 . Below, the changing moments, which the camshaft exerts on the driven element 3 , lead to a back and forth motion of the driven element 3 and thus of the blade 6 in the pressure spaces 10 until at least one of the pressure chambers 14 , 15 is filled completely with pressurized medium. This leads to higher wear and to the development of noise in the device 1 . Furthermore, in this operating phase, the phase position between the driven element 3 and the stator 2 oscillates at a high amplitude, which leads to noisy operation of the internal combustion engine.
To prevent this, in the device 1 a locking device 30 is provided. This is comprised of a locking pin 31 , which is arranged in a recess of the driven element 3 and which is forced in the direction of the sealing disk 12 by a spring. On the sealing disk 12 , a connecting element 32 is formed, in which the locking pin 31 is forced into a maximum advanced position or a maximum retarded position of the driven element 3 relative to the stator 2 . In this case, the locking pin 31 contacts the radial limiting walls of the connecting element 32 , wherein it simultaneously extends into the receptacle formed on the driven element 3 . In this way, a positive-fit, mechanical connection is produced between the driven element 3 and the stator 2 in a relative phase position, which corresponds to an optimum position for the starting and/or the idling of the internal combustion engine. In addition to the locking of the driven element 3 relative to the stator 2 in one of the maximum end positions, it can also be provided to lock both components relative to each other in a middle position. Advantageously, the sealing disk 12 is constructed from steel that can be hardened. The sealing disk 12 is subjected to a hardening method after the shaping, whereby this sealing disk can receive the forces transmitted via the locking pin 31 in a functionally reliable way. This leads to an increased service life of the device 1 .
Furthermore, means are provided, in order to force the locking pin 31 back into the receptacle when the device 1 is supplied with sufficient pressurized medium and thus to cancel the locking. In the shown embodiment, it is provided to pressurize the connecting element 32 with pressurized medium via pressurized medium channels 33 . The pressurized medium channels 33 are constructed as grooves formed in the side surface of the driven element 3 . These grooves extend from at least one of the pressure chambers 14 , 15 up to the connecting element 32 .
The pressurized medium led into the connecting element 32 forces the locking pin 31 against the force of the spring back into the receptacle, whereby the fixed phase reference between the driven element 3 and stator 2 is canceled.
Here, it is provided that the pressurized medium channels 33 communicate with the connecting element 32 only in a defined small angular interval of the phase position between the stator 2 and the driven element 3 .
The housing 11 is advantageously constructed as a sheet-metal housing, wherein the two housing elements 16 , 17 are each produced from a sheet-metal blank by a non-cutting shaping process. Here, for example, techniques such as deep-drawing methods are considered. By forming the housing 11 from a steel sheet-metal blank, a reliable sealing of the device 1 is guaranteed, whereby the device 1 can be used as a belt-driven camshaft adjuster. Such camshaft adjusters are typically arranged outside of the cylinder head, whereby a secure sealing of the device 1 is required. Leakage oil is collected by the formation of the housing 11 as a molded sheet-metal part within the device 1 and can be fed back into the cylinder head via channels formed on the cylindrical section 19 . Alternatively, between the section 19 and the camshaft, an annular gap can be formed, in order to lead leakage oil back into the cylinder head. The first housing element 16 is advantageously sealed relative to the cylinder head by a radial shaft seal 20 arranged on the section 19 .
Through the encapsulation of the stator 2 and the driven element 3 within the housing 11 , cost-intensive post-treatment for sealing the driven element 3 normally formed as a porous sintered component can be eliminated. Any small leakage through the sintered material or at the sealing points is kept within the device 1 by the housing 11 and can be fed back into the cylinder head.
In the embodiment, in which the pressure spaces 10 are closed pressure-tight by a sealing disk 12 on the side of the device 1 facing away from the camshaft, this sealing disk 12 can be used simultaneously as a compensating disk in order to compensate any tolerances between the two housing elements 16 , 17 .
FIG. 4 shows another embodiment of a device 1 according to the invention. In this view, the sealing disk 12 is removed. This embodiment is essentially identical to the first embodiment, which is why identical components are provided with identical reference numbers. In contrast to the first embodiment, here the stator 2 a is not constructed as a thin-walled, shaped sheet-metal part, but instead as a solid component. This component can involve, for example, a stator 2 a made from a sintered material. In this embodiment, the housing 11 fulfills the same functions as in the first embodiment (torque transmission, sealing of the pressure spaces 10 ), whereby the same advantages are achieved. The formations 21 engage in indentations 21 a formed on the stator 2 a . These indentations can be constructed cost-neutral on the sintered component, such that these are already taken into account in the shaping tool.
REFERENCE SYMBOLS
1 Device
1 a Control device
2 Stator
2 a Stator
3 Driven element
4 Wheel hub
4 a Central borehole
5 Blade groove
6 Blade
7 Inner circumferential wall
8 Outer circumferential wall
9 Side wall
10 Pressure space
11 Housing
11 a Molded element
12 Sealing disk
13 Spring element
14 First pressure chamber
15 Second pressure chamber
16 First housing element
16 a Weld connection
17 Second housing element
17 a Opening
18 Base
19 Section
20 Radial shaft seal
21 Formations
22 Collar
23 Boreholes
24 Drive wheel
25 First pressurized medium line
26 Second pressurized medium line
27 Rotational angle limiting device
28 Pin
29 Recess
30 Locking device
31 Locking pin
32 Connecting element
33 Pressurized medium channel
100 Internal combustion engine
101 Crankshaft
102 Piston
103 Cylinder
104 Traction mechanism drive
105 Traction mechanism drive
106 Inlet camshaft
107 Outlet camshaft
108 Cam
109 Cam
110 Intake gas-exchange valve
111 Exhaust gas-exchange valve | A device ( 1 ) for the variable adjustment of control times of an internal combustion engine, including a stator ( 2 ), a driven element ( 3 ) arranged coaxially thereto, with both components being assembled so as to rotate relative to one another, and both components define at least one pressure chamber ( 10 ) at least in the radial and circumferential directions, and a housing ( 11 ), separate from the stator ( 2 ) and the driven element ( 3 ) which encloses the stator ( 2 ) and the driven element ( 3 ) in an oil-tight manner, whereby the housing ( 11 ) seals and defines the pressure chamber in an axial direction. | 5 |
TECHNICAL FIELD
[0001] The invention relates to multimodality medical imaging systems for viewing anatomical structures and functions of a patient, such as combined x-ray Computed Tomography (CT) and Positron Emission Tomography (PET) scanners and, more particularly, to separating the scanners to facilitate use of one scanner independently of the other scanner.
BACKGROUND OF THE INVENTION
[0002] Tomographic imaging devices or cameras are frequently used to assist in the diagnosis and treatment of a variety of anatomical structures and physiologic functions within the body of a subject patient, while minimizing the need for invasive procedures. Such devices typically utilize scanners that obtain data or information about such structures and functions from the patient at specified, discrete locations along the length of a patient. Using this information, the camera produces a series of images, each depicting a cross-section of the body of the patient, in a plane generally perpendicular to the length of the patient, and at specified points along the length of the patient. Combined, successive images or a substantially continuous spiral image taken along the length of a patient can yield a relatively three-dimensional view of internal organs and tissues, or at least provide a cross-sectional view of bodily structures or functions at various places on the patient. Tomographic cameras are most frequently used to view and treat organs and other tissues within the head, torso and trunk of a patient and, in particular, diagnose and treat such ailments as heart disease, arteriosclerosis, cancer, and the like.
[0003] Tomographic imaging cameras are often identified by the “mode” or “modality” of radiation used by their scanners to obtain patient data. Well-known scanner modalities include the X-ray Computed Tomography (CT), Magnetic Resonance Imaging (MRI), Ultrasound (ULT), Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography (PET) scanners. Camera systems which combine two or more different scanners to obtain a greater variety of imaging information from a patient are referred to as “multimodality imaging systems.” Conversely, tomographic cameras utilizing the same mode to collect imaging information are referred to as having the same modality.
[0004] A tomographic camera utilizes a scanner having an array of radiation detectors forming a ring or bore that surrounds a patient. The scanner gathers information along a plane defined by the detector ring, which intersects the patient substantially perpendicularly to the length of the patient. Other processors and instruments coupled to the scanner form the tomographic image, based on information received from the scanner. To obtain information at successive points along the head, torso and trunk of a patient, the patient is supported horizontally on a patient table that translates or moves the patient horizontally through the bore of a tomographic camera.
[0005] It is often desirable to utilize two or more adjacent tomographic scanners of different modalities, in multimodality systems, to obtain a variety of imaging information from a single traverse of a patient through multiple scanner bores. This is highly desirable as a means of increasing efficiency (by completing two or more scans in one operation), increasing the accuracy of indexing, correlating or linking multimodality images to the same location along the length of the patient (by coordinating operation of the scanners to a single, controlled movement of the patient) and reducing the labor costs otherwise associated with separate, multimodality scanning operations.
[0006] In general, multimodality systems include a series of scanners, each having a different modality, supported by a single housing. Each scanner obtains different information about the patient, which, when combined, provides a better understanding of the patient. More specifically, multimodality cameras typically include a scanner of anatomical structures of the patient (e.g., CT, MRI and Ultrasound cameras) and a scanner of physiologic functions of the patient (e.g., SPECT and PET cameras). The series of scanners forms a relatively long bore, typically longer than the combined head and torso of taller patients and spanning the entire length of shorter patients. The patient is moved at a relatively slow rate through the lengthy multimodality scanning bore, while imaging information is obtained.
[0007] The residence time of a patient within the multimodality scanner bore closure typically is in the range of from less than a minute to as much as an hour or more. During much or all of this time, the patient is isolated from operators of the multimodality scanners and cameras, from caregivers who may need to treat the patient, adjust instruments connected to the patient, or perform interventional applications (i.e., image-guided biopsies and the like), and from caregivers who might otherwise attend to the patient, should the patient become upset or ill from ingested radio-pharmaceuticals, and the like. Moreover, the relatively lengthy isolation of the patient within the tight quarters of the bore can cause anxiety, such as claustrophobia, and other discomfort or stress in the patient.
[0008] These shortcomings of multimodality cameras make their use less desirable when all modalities of imaging are not required. For example, in the event use of only the first scanner of a multimodality system is needed, such as use of a CT scanner forming the front portion of the scanner bore, the patient will remain within the scanner bore. In that circumstance, the extended length of the bore forming an imaging area for the PET scanner is unused. Nevertheless, should interventional applications or other procedure require direct access to a patient by a caregiver, additional time and effort will be required to extend or withdraw the patient from either end of the multimodality scanner bore. Moreover, unnecessary levels of patient discomfort, stress and anxiety result.
[0009] Accordingly, there is a need for a multimodality tomographic imaging system that allows use of less than all scanners and corresponding adjustment of the length of the scanner bore, to provide more immediate patient access and to reduce the time and effort needed to handle or attend to the patient.
SUMMARY OF THE INVENTION
[0010] The invention comprises a system and method for creating medical images of a subject patient using a plurality of imaging devices, such as tomographic imaging scanners. The imaging devices each have a bore through which a patient is translated during scanning. The imaging devices can be moved apart to allow greater access to a patient between the bores.
[0011] In one aspect of the invention, open area is formed between the imaging devices along the path of the patient, through which a caregiver can attain line-of-sight visual contact with or other access to the patient. The access area size is variable by adjustment of the distance separating the imaging devices.
[0012] In another aspect of the invention, a mechanism aligns the bores of the imaging devices to allow multimodality scanning.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] For a more complete understanding of the present invention, and the advantages thereof, reference is now made to the following description taken in conjunction with the accompanying drawings, in which:
[0014] [0014]FIG. 1 is a schematic side view of a multimodality medical imaging system incorporating the present invention, with the imaging devices in an adjoining position;
[0015] [0015]FIG. 1A is a schematic front view a multimodality medical imaging system of FIG. 1;
[0016] [0016]FIG. 2 is a schematic side view of the multimodality medical imaging system of FIG. 1, with the imaging devices in a separated position;
[0017] [0017]FIG. 3 is a perspective view of a preferred embodiment of a multimodality medical imaging system incorporating the present invention, with the imaging devices in separate positions, similar to the positions illustrated in FIG. 2;
[0018] [0018]FIG. 4 is a top view of the system shown in FIGS. 3 and 4, with the imaging devices in separate positions;
[0019] [0019]FIG. 5 is a side top view of a the embodiment shown in FIG. 3, with the imaging devices in an adjoining position;
[0020] [0020]FIG. 6 is a front view of an imaging device and associated mechanism for actuating the device to move between adjoining and separated positions;
[0021] [0021]FIG. 7 is a partial perspective view of an alignment and patient table vertical actuating assembly of an imaging device;
[0022] [0022]FIG. 8 is a perspective view of two imaging devices taken from below the devices, illustrating the relative position of the alignment and vertical actuating structure shown in FIG. 7;
[0023] [0023]FIG. 9 is a perspective view of two imaging devices taken from below the devices, illustrating additional structure for aligning the devices in an adjoining position;
[0024] [0024]FIG. 9A is a detailed drawing of the a portion of the alignment structure shown in FIGS. 7 - 9 ;
[0025] [0025]FIG. 10 is a partial perspective view of one of the imaging devices, illustrating alternative structure for aligning the devices in an adjoining position; and
[0026] [0026]FIG. 11 is a perspective view of two imaging devices, illustrating further the alternative alignment structure shown in FIG. 10.
DETAILED DESCRIPTION
[0027] Shown in FIG. 1 is a multimodality medical imaging system scanner assembly 100 , having first and second imaging devices 110 and 120 . In the embodiment shown, each of the imaging devices 110 and 120 comprise at least a scanner having a modality of operation, and may also include associated scanner support structure and associated electronics. Further, in the embodiment shown, each of the imaging devices 110 and 120 includes a scanner opening or bore 112 and 122 (shown by broken lines), respectively, through which a patient table 130 extends and translates a subject patient 140 during a scanning operation. It will be apparent that imaging devices 110 and 120 may alternatively utilize scanners or detectors that obtain information about the patient 140 without being configured to form a bore, such as a partial closure, an arrangement of one or more planar detectors and other configurations capable of obtaining patient information. Moreover, it will be apparent that while scanner bores 110 and 120 are preferably circular, other configurations capable of obtaining imaging information may alternatively be utilized.
[0028] The patient table 130 serves as a patient support structure that also coordinates movement of the patient 140 with respect to operation of the scanners of the imaging devices 110 and 120 , to obtain patient imaging information at one or more desired locations along the length of the patient 140 . It will be apparent that a variety of available conventional patient table 130 designs would be suitable for these purposes. It will be apparent that the patient table 130 may be designed or operated to extend the patient 140 past the scanners of the imaging devices 110 and 120 in a variety of methods, such as at a continuous rate, at variable rates, in incremental displacements or a combination of such methods, as may be desired or suitable for the scanning operation to be conducted.
[0029] Alternatively, instead of the patient table 130 , the present invention may utilize the patient handling assembly more fully disclosed in co-pending U.S. application Ser. No. ______, filed on Oct. 19, 2001, entitled “Multimodality Medical Imaging System and Method With Patient Handling Assembly” [Docket No. 018171 ] and naming as inventors Mark DeSilets, Timothy Buskard, Joseph Carter, Jacco Eerden and Donald Wellnitz. The content of that application is incorporated herein by reference for all purposes.
[0030] The imaging devices 110 and 120 acquire, through their scanners, information from the patient 140 sufficient to form tomographic images of the patient. Each of the imaging devices 110 and 120 is coupled to one or more conventional tomographic imaging processor(s), utilizing conventional imaging software to form images from information received from the imaging devices 110 and 120 .
[0031] Preferably, the imaging devices 110 and 120 cooperate to obtain patient information through different modalities, to provide anatomical structure images and physiologic function images of the patient 140 . More specifically, imaging device 110 is preferably a CT scanner that utilizes X-rays as the mode of obtaining data from which images depicting the internal structure of the patient 140 are formed. On the other hand, imaging device 120 is preferably a PET scanner that utilizes positron emissions originating from a radio-pharmaceutical ingested by the patient as the mode of acquiring data from which images depicting primarily metabolic physiological functions within the patient 140 are formed. During operation, the entire body of the patient 140 is passed through the bores 112 and 122 of the respective imaging devices 110 and 120 , and their respective scanners, so that a collection of one or more images are obtained from each scanner. When scanning is complete, the patient is retracted in the opposite horizontal direction by the patient table 130 , typically at a faster rate than during the scanning operation, to withdraw the patient 140 from the scanner assembly 100 , to the starting position at the beginning of the scanning procedure.
[0032] Referring now to both FIGS. 1 and 1A, the scanner bores 112 and 122 of the imaging devices 110 and 120 are substantially circular, thus surrounding the patient during imaging scanning operations. The axes 112 A and 122 A of the respective circular openings of each of the bores 112 and 122 are aligned with each other and are preferably aligned with or at least substantially parallel to the path of travel of the patient 140 on the patient table 130 . This allows the patient table 130 to translate the patient 140 through the imaging devices 110 and 120 in one substantially continuous pass. Preferably, the center line of the patient 140 is substantially aligned with or at least substantially parallel to the axes 112 A and 122 A of the detector bores 112 and 122 by adjusting the height of the patient table 130 and the alignment of the table 130 with the bores 112 and 122 .
[0033] Referring to FIGS. 1 and 2, the imaging devices 110 and 120 are each supported within separate housing portions 110 H and 120 H, each of which are preferably formed from painted sheet metal and are electrically isolated from internal conductors. Alternatively, the housing portions 110 H and 120 H are formed from fiberglass or other non-conductive material. The housing portions 110 H and 120 H are each preferably formed in a unitary construction, and are adapted to be secured together in an adjoining position shown in FIG. 1, at opposing faces 110 F and 120 F, respectively. Housing portions 110 H and 120 H contain and support imaging devices 110 and 120 , respectively. The opposing faces of the two housing portions 110 H and 120 H abut and are secured together along seam line 170 in the adjoining position, below the level of the bores 112 and 122 of the imaging devices 110 and 120 .
[0034] The multimodality medical imaging system scanner assembly 100 includes an actuating mechanism 300 for positioning the housing portions 110 H and 120 H between adjoining and separate positions, as well as virtually any intervening position along a range of approximately 1.5 meters. It will be apparent that actuating mechanism 300 may alternatively be configured for shorter or longer ranges of motion, as desired. The actuating mechanism 300 actuates the rear imaging device 120 linearly and substantially along the aligned axes 112 A and 122 A of the housing portions 110 H and 12 H. The actuating mechanism 300 may employ a variety of mechanisms, such as a single or stacked set of ball or lead screws, cylinders, gears or the like, powered hydraulically, pneumatically electrically or by other desired power source.
[0035] [0035]FIGS. 1 and 2 show that the rearward housing portion 120 is driven, while the front housing portion 110 remains fixed, anchored to the underlying support surface, thereby allowing the patient table 130 to remain relatively stationary. However, it will be understood that actuating mechanism could alternatively adjust to position of both of housing portions 110 H and 120 H or only housing portion 110 H, if desired. When in the adjoining position bores 112 and 122 of imaging devices 110 and 120 in maintained in relatively fixed positions, by the abutting housing faces 110 F and 120 F or by a suitable alignment mechanism. A seam line 170 identifies the contact surfaces of the abutting housing faces 110 F and 120 F.
[0036] As is shown in FIG. 2, separation of the imaging devices 110 and 120 shortens the length of the bore of the medical imaging scanner assembly 100 and allows a caregiver 200 to have direct access to those portions of the patient 140 extending from the bore. When the assembly 100 is utilized in a singly modality, such as when use of only scanner 110 is desired, the actuating mechanism separates imaging devices 110 and 129 , preferably prior to scanning. The assembly 100 thus operates similarly to a single mode scanner, without the inconvenience of a lengthy and partially unused bore that would otherwise interfere with access to the patient 140 . Prior to use of the assembly 100 as a multimodality scanner, the imaging devices are 110 and 120 actuated into the closed position. In the closed position, with their respective bores 112 and 122 in held axial alignment and in fixed positions relative to each other, to facilitate image registration of the image information obtained by the imaging devices 110 and 120 .
[0037] [0037]FIGS. 3, 4 and 5 illustrate an embodiment in which an access area 160 is formed by the separation of the imaging devices 110 and 120 , when the imaging devices 110 and 120 are in the closed position. In this configuration, the abutting housing faces 110 F and 120 F extend below the access area 160 . FIGS. 3 and 4 illustrates that the caregiver 200 can have access to the entire length of the patient 140 . This is accomplished by configuring the actuating mechanism 300 (not shown in FIGS. 3, 4 and 5 ) to separate the imaging devices 110 and 120 by as much or more than the entire length of the patient 140 . Such separation allows unfettered access to virtually every portion of the patient extending between the imaging devices 110 and 120 , including the entire length of the patient 140 . FIG. 5 illustrates the relative position of the access area 160 , patient 140 and caregiver 200 , when the imaging devices 110 and 120 are actuated into the closed position, with the head of the patient 140 extending from the CT scanner of imaging device 110 . While the caregiver 200 is shown to be an individual, it will be apparent that the term “caregiver” includes any means of providing monitoring, diagnostic treatment, comfort or other care services to the patient 140 , such as by use of robotics or other equipment.
[0038] The formation of access area 160 is disclosed in co-pending U.S. patent application Ser. No. ______, entitled “Multimodality Medical Imaging System and Method With Intervening Patient Access Area” [Docket No. US018172], naming as inventors Mark DeSilets, Jacco Eerden and Horace H. Hines, filed on Oct. 19, 2001. The content of that application is incorporated herein by reference for all purposes. Access area 160 allows a caregiver 200 to have access to the patient 140 as the patient table 130 translates the patient 140 from the CT scanner 110 to the PET scannner 120 during imaging operations, when the housing portions 110 H and 120 H are in the closed position.
[0039] Maintaining the imaging devices 110 and 120 in fixed relation to each other and in axial alignment when the assembly 100 is in the closed position allows images created from data the scanners separately obtain to be registered correlated, indexed or linked in relation to each other. This is accomplished using information indicating the position of the patient 140 on the patient table 130 . More specifically, the patient table 130 includes means for detecting the displacement and position of the patient relative to the multimode scanners of the imaging devices 110 and 120 . This information can be used in combination with information indicating the fixed distance separating the scanning planes of the imaging devices 110 and 120 to register, correlate, pair or link the images from each of the devices 110 and 120 to a particular location or point on the patient 140 . Each tomographic image obtained from imaging device 110 may thus be paired with or indexed to a corresponding tomographic image obtained from detector 120 with reference to substantially the same location along the length of the patient 140 .
[0040] Referring now to FIG. 6, shown is a front view of the imaging device 120 , supported for movement by four support wheels 310 (only the front two wheels shown), and an associated actuating mechanism 300 for driving the imaging device into engagement with and away from the imaging device 120 . The actuating mechanism 300 extends below the imaging device 120 and comprises a drive beam 320 secured to an underlying support surface and drive wheels 340 frictionally engaging and driving along opposite sides of the drive beam 300 . The drive beam is substantially aligned with the axes 112 A and 122 A or the bores 112 and 122 . The drive beam 340 includes upper and lower flanges 350 and 360 , respectively, forming channels for guiding the drive wheels 340 . Preferably, a pair of drive wheels 340 engage and are sufficiently spaced along each of the lateral surfaces of the drive beam 320 , to maintain the bore 122 of the imaging device 120 in alignment with the bore axes 112 A and 122 A. The drive wheels 340 are preferably actuated by electrical motors (not shown) or other suitable power source. The support wheels 310 run on stainless steel wear plates 370 secured to the underlying surface and extending along the path of travel of the support wheels 310 .
[0041] [0041]FIGS. 7, 8, 9 , and 9 A illustrate a preferred alignment mechanism 400 for laterally and axially aligning the imaging devices 110 and 120 when in the closed position. For clarity, the actuating mechanism 300 and the support wheels of the imaging device 120 are not shown. The alignment mechanism 400 comprises a support frame 410 secured to and extending rearwardly from the front imaging device 100 . The support frame 410 is secured by a pair of anchor flanges 420 to the underlying support surface against longitudinal and lateral movement. Secured to and extending rearwardly from the support frame 410 are a pair of alignment lugs 430 , each positioned approximately an equal distance on opposite sides of the associated bore axis 112 A. The alignment lugs 430 are each preferably cylindrical, with spherical bearing surfaces 440 facing the rear imaging device 120 . The support frame 410 extends into a frame recepticle 450 extending into the housing 122 H of the rearward imaging device 120 and aligned with the bore axes 112 A and 122 A. Mounted within the rear wall of the frame recepticle 450 are a pair of female alignment sockets 460 which are engaged by the alignment lugs 430 as the imaging devices 110 and 120 are brought together into the closed position. As is best shown in the detail drawing of FIG. 9A, the alignment sockets 460 have conical inner surfaces, which bear against the cylindrical bearing surfaces of the alignment lugs 430 to align the imaging devices 110 and 120 .
[0042] Referring now to FIGS. 10 and 11, shown is an alternate configuration of the alignment mechanism 400 , in which the alignment lugs 430 and their corresponding alignment sockets 460 are mounted at locations adjacent the sides of the respective imaging devices 110 and 120 . This configuration may also be combined with the configuration of the alignment mechanism 400 shown in FIGS. 7, 8 and 9 .
[0043] The support frame 410 also may be utilized as a vertical actuator to vertically position a patient table mounted on the support frame, between the imaging devices 110 and 120 , in accordance with U.S. patent application Ser. No. ______, entitled “Multimodality Medical Imaging System and Method With Patient Handling Assembly” [Docket No. US018171], previously incorporated by reference herein.
[0044] Having thus described the present invention by reference to certain of its preferred embodiments, it is noted that the embodiments disclosed are illustrative rather than limiting in nature and that a wide range of variations, modifications, changes, and substitutions are contemplated in the foregoing disclosure and, in some instances, some features of the present invention may be employed without a corresponding use of the other features. Many such variations and modifications may be considered obvious and desirable by those skilled in the art based upon a review of the foregoing description of preferred embodiments. Accordingly, it is appropriate that the appended claims be construed broadly and in a manner consistent with the scope of the invention. | The invention comprises a system and method for creating medical images of a subject patient using a plurality of imaging devices, such as tomographic imaging scanners. The imaging devices each have a bore through which a patient is translated during scanning. The imaging devices can be moved apart to allow greater access to a patient between the bores. | 8 |
This is a continuation of copending application Ser. No. 07/361,593 filed on Jun. 2, 1989, now abandoned; which is a divisional of prior application Ser. No. 153,935, filed Feb. 9, 1988 now U.S. Pat. No. 4,853,571; which was a divisional of prior application Ser. No. 022,894, filed Mar. 6, 1987 now abandoned, which was continued as application Ser. No. 07/188,629 filed May 2, 1988, now U.S. Pat. No. 4,813,243.
BACKGROUND AND SUMMARY OF THE INVENTION
This invention relates to drives for clothes washing machines of the type having a cabinet in which an agitator is mounted on a vertical axis and is oscillated back and forth with a perforated spin tub which in turn is mounted within a water tight container, the spin tub and the agitator rotating continuously in one direction to give a spin action, said cabinet containing an electric motor and driving means for the agitator and spin tub and/or clothes washing machines incorporating such drives.
It is an object of the present invention to provide a drive for a clothes washing machine of the type described and/or a clothes washing machine incorporating such a drive which will at least provide the public with a useful choice.
Accordingly, in one aspect the invention consists in a drive for a clothes washing machine of the type having a cabinet in which an agitator is mounted on a vertical shaft so as to rotate therewith and is oscillated back and forth within a coaxially mounted perforated spin tub, the spin tub and the agitator rotating continuously in one direct to give a spin action, and the perforated spin tub and agitator in turn being mounted within a water tight container, said cabinet containing an electric motor and driving means to oscillate said agitator back and forth or rotate said spin tub continuously in one direction, and is characterized in that at least one part of said spin tub one part rotatable with said agitator are axially movable relative to each other; in that each said one part has a part of an interconnecting means associated therewith; and in that interconnection actuating means are provided operable in a washing sequence to actuate said parts of said interconnecting means by relative axial movement of said at least one part rotatable with said agitator and said at least one part of said spin tub to connect said agitator to said spin tub when spin action is required and to actuate said parts of said interconnecting means to separate by opposite relative axial movement to permit said agitation of said agitator without material relative movement of said spin tub during a washing phase in said sequence.
In a further aspect the invention consists in a drive system comprising an electric motor having a stator carrying energizable windings on poles thereof, a shaft carrying said rotor and being rotatable in frames forming part of said electric motor, said frames also mounting said stator of said motor, a clothes washing agitator, a perforated spin tub in a washing container in turn mounted in a cabinet, with said motor, said clothes washing agitator and said spin tub being mounted co-axially on said shaft and rotatable thereon in a mode selected from an agitating mode in which said rotor, said shaft and agitator are oscillated backwards and forwards over an arc of movement and said spinning tub remains substantially stationary and a spinning mode in which said rotor, said spin tub and said agitator are rotated continuously in one direction. At least one part of said spin tub and one part rotatable with the agitator are axially movable relative to each other, each said one part having a part of an interconnecting means associated therewith, and interconnecting actuating means are provided operable in a washing sequence to actuate said parts of said interconnecting means by relative axial movement of said at least one part of said agitator and said at least one part of said spin tub to connect said agitator to said parts of said interconnecting means to separate by opposite relative axial movement to permit said agitation of said agitator without material relative movement of said spin tub during a washing phase in said sequence.
In a still further aspect the invention consists in a drive for a clothes washing machine of the type having a cabinet in which an agitator is mounted on a vertical shaft so as to rotate therewith and is oscillated back and forth within a perforated spin tub, the spin tub and the agitator rotating continuously in one direction to give a spin action and the perforated spin tub and agitator in turn being mounted within a water tight container, said cabinet containing an electric motor and driving means to oscillate said agitator back and forth or rotate said spin tub continuously in one direction, characterized in that said drive includes interconnecting means provided between said driving means and said spin tub, said interconnecting means including actuating means actuable by the presence or absence of a substantially predetermined quantity of water in said container so that when at least said predetermined amount of water is present in said container said interconnecting means are disconnected between said driving means and said perforated spin tub and when water is substantially absent from said container said interconnecting means connect said driving means to said perforated spin tub so that said perforated tub will rotate with said driving means.
In a still further aspect the invention consists in a drive system for a clothes washing machine of the type having a cabinet in which an agitator is mounted on a vertical shaft so as to rotate therewith and is oscillated back and forth by an electric motor within a coaxially mounted perforated spin tub, the spin tub and the agitator being rotated continuously in one direction by said electric motor to give a spin action, and the perforated spin tub and agitator in turn being mounted within a water tight container, said cabinet containing an electric motor, said drive selectively oscillating said agitator back and forth and rotating said spin tub and agitator continuously in one direction, said drive including at least one part of said spin tub and one part rotatable with said agitator which are axially movable relative to each other, each said one part having a part of an interconnecting means associated therewith; and interconnection actuating means are provided operable in a washing sequence to actuate said parts of said interconnecting means by relative axial movement of said at least one part rotatable with said agitator and said at least one part of said spin tub to connect said agitator to said spin tub when spin action is required and to actuate said parts of said interconnecting means to separate by opposite relative axial movement to permit said agitation of said agitator without material relative movement of said spin tub during a washing phase in said sequence.
In a still further aspect the invention consists in an electric motor comprising a stator carrying energizable windings on poles thereof, a rotor, a motor frame, said frame having bearing mountings in a central disposition and having coacting locating means near outer edges thereof arranged to hold said frame with said bearing mountings separated and axially aligned, said frame having stator locating means arranged to hold the outer cylindrical surface of a stator concentric with said bearing mounting of said frame, a pair of bearings mounted in said bearing mountings, a shaft rotatably mounted in said bearings and carrying said rotor, said rotor comprising a backing ring of a magnetic material, a series of permanent magnets spaced apart on an inner surface of said backing ring and rotatable exteriorly of said stator windings, a hub mounted on said shaft, and a backing ring support holding inner faces of said permanent magnets concentric with said shaft.
In a still further aspect the invention consists in a clothes washing machine comprising a cabinet, a container for wash water suspended in said cabinet, an electric motor mounted below said container, an agitator within said container, a drive shaft between said electric motor and said agitator so that said electric motor directly drives said agitator, a spin tub within said container and within which said agitator is mounted, said spin tub being rotatably mounted on said drive shaft, sealing means between said drive shaft and said container and interconnecting means having two positions in one of which positions said interconnecting means connects said spin tub to said agitator so as to rotate therewith and in which other position said spin tub is disconnected from said agitator, an electric supply means arranged to drive said agitator in a forward and reverse motion to give agitation to clothes placed within said spin tub in one mode of operation when said spin tub is disconnected from said agitator, and arranged to rotate said spin tub and said agitator continuously in one direction when the spin tub and the agitator are interconnected by said interconnecting means.
In a still further aspect the invention consists in a clothes washing machine comprising a cabinet, a container for water suspended in said cabinet, an electric motor mounted below said container, an agitator within said container, a drive shaft between said electric motor and said agitator so that said electric motor directly drives said agitator, a spin tub within said container and within which said agitator is mounted, said spin tub being rotatably mounted on said drive shaft, sealing means between said drive shaft and said container, and interconnecting means having two positions, in one of which positions said connecting means connects said spin tub to said agitator so as to rotate therewith and in which other position said spin tub is disconnected from said agitator, said electric motor being arranged to drive said agitator in a forward and reverse motion to give agitation to clothes placed within said spin tub in one mode of operation when said spin tub is disconnected from said agitator, and arranged to rotate said spin tub and said agitator continuously in one direction when the spin tub and the agitator are interconnected by said interconnecting means, at least one part of said spin tub and one part rotatable with said agitator being axially moveable relative to each other, each said one part having a part of said interconnecting means associated therewith, and interconnection actuating means are provided operable in a washing sequence to actuate said parts of said interconnecting means by relative axial movement of said at least one part rotatable with said agitator and said at least one part of said spin tub to connect said agitator to said spin tub when spin action is required and to actuate said parts of said interconnecting means to separate by opposite relative axial movement to permit said agitation of said agitator without material relative movement of said spin tub during a washing phase in said sequence.
To those skilled in the art to which the invention relates, many changes in construction and widely differing embodiments and applications of the invention will suggest themselves without departing from the scope of the invention as defined in the appended claims. The disclosures and the descriptions herein are purely illustrative and are not intended to be in any sense limiting.
The invention consists in the foregoing and also evisages constructions of which the following gives examples.
BRIEF DESCRIPTION OF THE DRAWINGS
One preferred form of the invention will now be described with reference to the accompanying drawings, in which
FIG. 1 is a cross -sectional elevation of a clothes washing machine constructed according to the invention, with some parts shown at 45° plan to other parts;
FIG. 2 is an enlarged view partly in cross section of a water container, spin tub, agitator, drive and electric motor; and
FIGS. 3 and 4 are respectively a plan view cross section of preferred motor frames incorporated in the invention in the preferred form;
FIG. 5 is a further enlarged view of a seal shaft and bearings being part of FIG. 2;
FIG. 6 is a partial cross section of an alternative embodiment of the invention;
FIG. 7 is a partial cross section of a further alternative embodiment of the invention;
FIG. 8 is a partial elevation at 45° to the view of FIG. 1; and
FIG. 9 is a rear view of an agitator motor forming part of the invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings, a clothes washing machine comprises a cabinet 1 of square cross section which has mounted in it an electric motor 2 constructed according to the present invention as will be described further later. A water container 3 is suspended within the cabinet 1 by suspension rods 4 and springs 5, and, for example, four springs and rods are provided, and the motor and other mechanisms are attached to the container 3. The springs are provided in the corners of the square cross section cabinet 1; accordingly, parts of the rod are shown in sectional view in FIG. 8 which is at 45° to the other sectional view of FIG. 1. By "water" is meant washing liquid, e.g. water and detergent. Contained within the water container 3 there is a perforated spin tub 6 and within the spin tub is an agitator 7. An opening lid 9, shown only partially, is provided through which clothes may be inserted into the container and within the spin tub 6, and the spin tub is partly balanced by upper balancing ring 10 shown only in the rear at one side in FIG. 1. The springs terminate in hooks 12 which engage in apertures 13 in the container base molding 29. The agitator 7 is mounted on a hollow drive shaft 11 so as to rotate therewith but is slidable axially thereon. The spin tub 6 is coaxially mounted on the shaft 11 so as to be rotatable and also slidable axially thereon.
The motor 2 is constructed as follows. A rotor 15 has a backing ring 16 (FIG. 2) and the backing ring is formed from a strip of magnetic material, for example a silicon steel alloy, and the strip of steel is coiled on edge with adjacent surfaces lightly insulated and touching each other to provide a short hollow cylinder or annular helix. Inside the helix there is provided a series of magnets 17, the backing ring 16 being expanded slightly before being placed over the magnets placed in a mold. The magnets are permanent magnets of a material capable of being magnetized to a high flux value, e.g. "neodymium" iron made by Magnaquench Inc., and the annulus and the magnets are held in place by a plastic member 18 which has a hub 19, a disc or spoked connector portion 20, and a substantially cylindrical element 21, the member 18 being molded over the backing ring and magnets so as to maintain the inner faces of the magnets 17 concentric with the axis of the hub 19.
The stator 25 of the motor has a magnetic core which comprises a strip of magnetic material, again preferably a silicon steel alloy or other low hysteresis steel, which is preformed to provide spaced apart pole pieces, and again this strip is formed by bending on edge to form an annular helix in the form of a hollow cylinder with the poles 8 formed by the stacked pole pieces pointing outwardly. As may be seen in FIG. 9, the poles S are connected together by a narrow band 14 so that bending on edge is relatively easily effected. To provide insulation for windings on the poles of the core, a top insulating molding 22 is placed on one side of the poles and a bottom insulating molding 23 placed on the opposite side, meeting at a joint line 24. Windings are placed on the moldings wound around each pole and such windings 26 are effected on the poles directly.
It is preferable that the stator be wound in a three phase star connected mode and the windings are made and connected using known techniques.
The stator 25 and the rotor 15 are mounted as will shortly be described.
The water container 3 is preferably an injection molding, and the base 29 has motor support columns 30 preferably braced with stiffening webs 31. These webs extend to the outer perimeter of the container 3 and are molded integrally with the container.
The motor 2 includes two bearing frames 32 and 33 which comprise injection moldings of a die cast metal or plastic material or preferably steel pressings or plastic material. Preferably the frames 32 and 33 are produced from the same mold or set of dies, thus ensuring equality of dimensions between the two frames. The frames are carefully designed and made so that the bearing moldings 27 and 28 are concentric with locating pins or dimples S4 and corresponding holes 35 at the periphery of the frames and with the external angle 36 in which the inner corner 37 of the stator 25 fits with an interference fit.
Stiffening depressions 49 are provided to stiffen the frames, and on assembly one frame is assembled rotated 45° relative to the other frame to provide correct matching of holes and dimples.
Bearings 38 and 39 fit in the bearing mountings 27 and 28 and the bearings are spaced apart by a spacing tube 40 which encircles the drive shaft 11. The hub 19 is fixed to the shaft 11 by a bolt 41 engaging a nut 42 held in the hollow of the shaft 11 by the shaft 11 being swaged down to provide splines which engage corresponding spline spaces 42 in the hub 11. For transport purposes a further nut 43 holds the assembly supported by suspension rods and fixed to a cabinet member 44.
The spin tub 6 comprises a stainless steel perforated hollow cylinder 45 fixed to a plastic extruded base 46, e.g., by spinning the lower edge of the cylinder 45 on to the periphery of the plastic base 46. If desired, a lower balancing ring 47 is provided and the balancing rings are each comprised as a hollow ring with baffles and liquid container therein and the rings are each closed by an annular disc 48. One balancing ring, preferably the ring 10, was found to give reasonable balance while spinning.
A plurality of bridges 50 are provided at spaced intervals with gaps between them, and the bridges connect the balancing ring 47 (if fitted) to an air chamber in the form of a bell 51 having an open mouth directed downwardly and a tube 52 integral therewith which surrounds the shaft 11. A low friction plastic bearing 53 enables the plastic base 29 and consequently the spin tub 6 to rotate and slide axially on the drive shaft 11.
A series of downwardly directed dog clutch teeth 55 (FIG. 2) of a high impact duty material, e.g. a high impact duty plastic material, are carried by a carrier 56 riveted, screwed or otherwise fixed to the air chamber 51, e.g. by screws 57. A ring 60 carries coacting dog clutch teeth 61 also of a high impact duty material, and the ring 60 is rotatable by and axially slidable on the drive shaft 11, e.g. by engagement of splines on the ring 60 with splines on the drive shaft 11. The agitator 7 has a boss 62 with inner splines 63 engaging outer splines 64 on the ring 60 so that rotation of shaft 11 results in rotation of the teeth 61 and the agitator 7, and the boss 62 slides axially on the drive shaft 11 as may be seen by comparing the "up" position of elements on the left hand side of FIGS. 1 and 2 with the "down" position on the right hand side.
The air chamber 51 is designed to provide a flotation or buoyancy force resulting from the entrapment of air in the air tight chamber 51 when water closes the perimeter of the lower edge of the air chamber 51. In the event that water enters the air chamber 51, e.g. because of turbulence during agitation, the lower face could be closed off with the disc 54.
The buoyancy force is at least sufficient to lift the spin tub 6 and the agitator 7 when a substantially predetermined volume of water is provided in the container 3, and the spin tub and agitator 7 are shown in the "up" position on the left hand side of FIGS. 1 and 2 and in the "down" position on the right hand side. When the spin tub 6 is in the up position, i.e. supported by flotation of the air chamber 51, the teeth 55 and the teeth 61 are disengaged from each other and the agitator may be rotated freely over any desired rotational movement independent of the spin tub 6. When water is absent or substantially absent from the container 3, the spin tub 6 sinks until the teeth 55 and 61 are engaged. The spin tub 6 and agitator will then be rotated as one unit and this rotation will be effected continuously in one direction to spin clothes in the spin tub to a drier condition in the known way. To assist in freeing frictional contact between the axially sliding parts during up and down movement of the spin tub during filling with, and emptying of water, control means are provided for controlling motor 2 to give a slow agitating action, i.e. forward and reverse rotation over a small arc of movement. At each reversal the dogs will reverse contact and be free of each other for a short time due to clearances as between the dogs and spaces between the dogs.
To assist in fixing the spin tub against rotation during agitation, i.e. when the agitator is in the up position, the upper edge 67 of the spin tub may contact a frictional surface 68 on the underside of a top member 69 of the container 3.
The agitator 7 has external blades 81 thereon which extend from the surface of both column 82 and the upper surface of an upper coned disc 83. There is a space 84 between the disc 83 and the upper surface 85 of the air chamber 51; this space may be divided with radial vanes (not shown), since the purpose of the space arrangement is to provide a centrifugal impeller. Such an impeller may be otherwise provided, e.g. an independent centrifugal pump could be provided.
Outlet openings 86 are provided from the space 84 at or near the outer edge of the disc 83, the outer edge 87 of which is turned downwardly and operates in close proximity to the inner edge of the balance ring 46. As a result of this construction a pumping action is given, pumping water from the center of column 82 from apertures 88 through space 84 below balance ring 46 to space 86 between the spin tub 6 and the container 3, and lint is restrained in this space before the water re-enters the spin tub through the holes 90. If desired, a container may be mounted on the column 82, such container holding a clothes conditioner in the known way.
electronic commutation equipment 65 is provided on an annular printed circuit board in an annular container 66 mounted below the stator 25, and the electronic commutation equipment is preferably enclosed in a compound for protection and heat sinking, and is such as to enable the electric motor 2 to move in a backward and forward motion thus causing the shaft 11 to be oscillated backward and forth resulting in the agitator 7 being also rotated in a back and forth motion to give the well known washing motion. Such electronic commutation equipment is described in copending New Zealand Application No. 213489/213490 and corresponding UK Patent Application 8622289 and U.S. patent application 06/908,176 which are incorporated herein by reference. The electronic commutation equipment 65 is also arranged to drive the motor continuously to give a spin action, and to drive the spin tub with the agitation when the absence of water from the container 3 results in engagement of teeth 55 and 61 as above described.
However, when the agitator is preferably given a slow agitation motion and the container 3 has water in it, at least to a predetermined level, the flotation force of air in air chamber 51 causes the air chamber, spin tub agitator to rise. The teeth 61 and the agitator may now move independently of the spin tub and thus may be oscillated back and forth at a desired rate and over any desired angle of rotation to give a washing action without material movement of the spin tub.
To provide seals between the drive shaft 11 and the base 29 of the water container, a short cylinder of, e.g., steel, 70 (FIG. 5) is fixed to the upper frame 32 by a screw 71, and a flange 27 holds the bearing 38 in place. The short cylinder 70 supports a seal 72 against the wall 73 of an aperture in the water container base 29, and a disc 74 holds a further seal 75 against the shaft 11, being reinforced by a backing ring 76. A played disc 77 holds a further seal 78 against the shaft 11 reinforced also by a spring 79, the flange 80 sitting within a short cylinder 81 integral with disc 74.
The seal 72, short cylinder 81, disc 74 and seal 75 are integral with each other, and the played disc 77, seal 78 and flange 80 are integral with each other. Both units are made of "Neoprene" or other known flexible seal material.
A pump 95 is provided for the purpose of draining the container 3, and the pump 95 is mounted directly about an opening 96 in a lower part of the container 3 and thus a single flexible tube can run from the pump outlet through the back of the cabinet to the user drain connection point.
It is to be noted that the bearings 37 and 38 are a slip fit on the drive tube 11, and tightening of the bolt 41 and a cap 91 by a screw 92 clamps both bearings into position. Removal of the rotor securement screw 92 and the bolt 41 can result in the drive tube 11 being removed from above and the motor rotor 15 being removed from below. The motor 2 is removable as a unit after removing also the screws 93 holding the frames 32 and 33 in position. Thus, for maintenance this removal can be readily effected. Furthermore, following removal of the securement screw 92, the agitator and agitator hub can be removed and the spin tub assembly then lifted off from above. Thus, maintenance is very simple.
It is also to be noted that because the spin tub and its contents float during the agitation phase, no thrust bearing is required. Also, the bearing 53 operates under water and only under low speed conditions, i.e. the agitator speed relative to the substantially stationary spin tub, and therefore the bearing need only be a light duty bearing.
An alternative form of interconnection means is provided as follows:
The agitator 7 has associated with it a bell 100, both being fixed to the shaft 101 by a bolt 102. The shaft 101 corresponds to the shaft 11 and is driven by an electric motor as above described.
Within the bell 100 is a rise and fall member 103 which is a plastic molding sealably attached by flexible bellows 105, e.g. of "Neoprene", to the outer edge 106 of the plastic member 103 and to the edge of the bell 100. A further flexible bellows is sealably attached to the member 103 and to the hub of the bell 100. The member 103 has prongs or dogs spaced at intervals thereon, and such prongs or dogs engage in the spaces between castellations 109 in the bottom of the spin tub 6. A spring (not shown) is provided which exerts a downward force from the hub 108 on the member 103, and the cavity 110 is open to the atmosphere through a cross hole or notch 111 in the hub and a series of holes in the shaft or drive tube 101. This arrangement is such that when the container 3 is emptying, the spring moves the member 103 downwardly so that the prongs or dogs 104 engage in the spaces between the castellations 109 and thus the spin tub will move with the agitator and be rotated with that agitator continuously for the purpose of spinning. However, when the container 3 has water in it to a predetermined level, the hydrostatic water pressure on the undersurface of the member 103 causes that member to rise against the pressure of the spring, air venting through the air holes above-mentioned, and the prongs or dogs are then raised out of contact with the spin tub and the agitator may now move independently of the spin tub and thus may be oscillated back and forth to give washing action.
In a further alternative arrangement of the spin tub to agitator interconnecting means shown in FIG. 7, the agitator 7 is combined with a hub 110 fixed by a bolt 111 to a solid splined shaft 112. An air chamber in the form of a bell member 115 is a slidable fit on the shaft 112 and has air entrapment spaces 116 in which air is trapped by rising water in the container 3 when the latter is being filler preparatory to agitation occurring. The bell 115 then acts as a float, raising detents or dogs 113 from engagement with castellations 107, as shown on the right hand side of FIG. 7, to a disengaged position as shown on the left hand side of FIG. 7.
A least in the preferred forms, the invention provides the following advantages:
1. The electric motor assembly and construction is integrated with the drive system in a manner such that a simple shaft and pair of bearing support the rotor at one end of the agitator and spin tub at the other end, avoiding the need for separate shafts and bearings for the motor and for the agitator and spin tub drive.
2. The mounting of the stator and the rotor outboard of the lower motor frame enable ready replacement of the stator and/or rotor.
3. The mounting of the electronics in an annular disk associated with the stator of the motor reduces the length of interconnecting wiring and enables a compact factory wired unit to be provided. | An electric motor (2) for a clothes washing machine including the motor and a drive, the motor having a stator (25) held outboard of a frame carrying bearings (37, 38) in which a shaft (11) rotates, the shaft carrying the rotor (21) outboard of the stator (25), and permanent magnets (17) on an inner face of the rotor. The stator (25) is formed as an annular helical yoke edgewise wound from a strip of magnetic material and having an inner face and an outer face, the strip having pole pieces (8) formed integrally therewith extending from one edge of the strip and the strip being edgewise wound whereby the pole pieces coincide in stacked groups to form a plurality of poles arranged at equally spaced intervals extending radially outwardly from the outer face of the yoke. Energizable stator windings (26) are wound directly on the poles (8) of the stator and are adapted to be energized through an electronic commutation circuit (65,66) and the rotor (21) is mounted for rotation exteriorly of and relative to the stator, the rotor comprising a backing ring (16) of magnetic material and a series of permanent magnets (17) held at spaced-apart intervals on an inner surface of the backing ring (16) and opposing the poles (8) of the stator (25). | 3 |
BACKGROUND
1. Field of Invention
This invention relates to fire protection, specifically, portable roof top sprinklers.
BACKGROUND
2. Description of Prior Art
Current methods used to prevent houses from burning during a fire is to place a standard lawn sprinkler and hope it doesn't turn over. The current roof top sprinklers as seen in U.S. Pat. No. 8,24,020 issued to Randall Harward on Apr. 25, 1989, cannot be adjusted to the angle of different roof structures, causing the system to tip over and become useless in its purpose. Installing a sprinkler system within the construction of the roof top as seen in U.S. Pat. No. 5,263,543 issued to Ralph Nigro on Nov. 23, 1993, could interfere with the integrity of the house if a leak should occur, causing costly damage to the structure before it would be detected.
OBJECTS AND ADVANTAGES
Accordingly, several objects and advantages of this invention are:
a. To provide a portable fire protection system.
b. To provide a portable fire protection system that is inexpensive.
c. To provide a portable fire protection system that can be mounted on different types of surfaces.
d. To provide a portable fire protection system that can be mounted on different shapes of surfaces.
e. To provide a portable fire protection system that can be manufactured from readily available materials.
f. To provide a portable fire protection system that can be mass produced using current manufacturing procedures.
SUMMARY OF INVENTION
The present invention is a fire protection system which can be mounted on any uneven or odd shaped surface of a roof without requiring any additional mounting apparatus. The fire protection system has a plurality of sprinkler assemblies connected together in series. Each sprinkler assembly has a water manifold pipe, a pair of U-shaped supports, and a sprinkler head connected to the water manifold pipe. Each U-shaped support has a pair of legs with support rotator discs affixed to upper ends of the legs for pivotally connecting the U-shaped supports to the water manifold pipe. The manifold pipe extends through manifold rotator discs affixed thereto. Locking bolts extends through respective semi-circular slots formed in the rotator discs of the U-shaped supports and the manifold rotator discs for locking the U-shaped supports in a selected pivotal angle of adjustment. During use, the support legs of the front and rear U-shaped supports are supported by front and rear roof sections of a house with the apex of the roof extending between the pair of U-shaped supports.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a perspective view of the fire protection system.
FIG. 2 shows an exploded perspective view of the fire protection system.
FIG. 3 shows a perspective view of the Water manifold assembly with a sprinkler head attached.
FIG. 4 shows a perspective view of the outside stand assembly with rotator plates attached.
FIG. 5 shows a perspective view of the inside stand assembly with rotator plates attached.
FIG. 6 shows a perspective view of a multitude of fire protection systems attached to the roof of a house with a spray of water emitting from the spray heads.
REFERENCE NUMERALS IN DRAWINGS
18 Fire Protection Sprinkler system
20 Water manifold
22 a Left side rear support rotator disc
22 b Right side rear support rotator disc
23 a Left side rear support rotator disc slot
23 b Right side rear support rotator disc slot
24 a Left side front support rotator disc
24 b Right side front support rotator disc
25 a Left side front support rotator disc slot
25 b Right side front support rotator disc slot
26 a Left side water manifold rotator disc
26 b Right side water manifold rotator disc
27 a Left side water manifold rotator disc slot
27 b Right side water manifold rotator disc slot
28 Water manifold connecting plug
30 a Left side threaded nut
30 b Right side threaded nut
32 a Left side bolt
32 b Right side bolt
34 Sprinkler head assembly
36 Water manifold hose bib assembly
40 Water manifold to sprinkler assembly connector tee
42 a Left side rear support leg
42 b Right side rear support leg
44 a Left side rear support leg adjuster tube
44 b Right side rear support leg adjuster tube
46 a Left side rear support leg adjuster lock device
46 b Right side rear support leg adjuster lock device
48 a Left side rear support adjuster leg
48 b Right side rear support adjuster leg
49 a Left side and Right side rear support leg connector
49 b Left side and Right side front support leg connector
50 a Left side front support leg
50 b Right side front support leg
51 a Left side front support leg adjuster tube
51 b Right side support leg adjuster tube
52 a Left side front support leg adjuster lock device
52 b Right side front support leg adjuster lock device
53 a Left side front support leg adjuster
53 b Right side front support leg adjuster
54 House
55 Water Spray
DETAILED DESCRIPTION
The preferred embodiment of the Fire Protection Sprinkler system of the present invention is illustrated in FIG. 1, a perspective view of the fire protection system. The water manifold 20 freely supports the left side rear support rotator disc 22 a , right side rear support rotator disc 22 b , left side front support rotator disc 24 a , and right side front support rotator disc 24 b at the through hole at approximately the center of the diameter of the discs. The planer surface of the left side rear support rotator disc 22 a , right side rear support rotator disc 22 b , left side front support rotator disc 24 a , right side front support rotator disc 24 b are positioned perpendicular to the surface of the water manifold 20 . The left side rear support rotator disc 22 a and left side front support rotator disc 24 a are positioned to the left side of the water manifold 20 closest to the water manifold hose bib assembly 36 . The right side rear support rotator disc 22 b and right side front support rotator disc 24 b are positioned at the right side of the water manifold 20 closest to the water manifold connection plug 28 . The left side water manifold rotator disc 26 a , is fixed securely at the left side of the water manifold 20 so that the rotational movement along the linear axis of water manifold 20 is transferred to the axis of the left side water manifold rotator disc 26 a . The right side water manifold rotator disc 26 b , is fixed securely on the right side of the water manifold 20 so that the rotational movement along the linear axis of the water manifold is transferred to the axis of the right side water manifold rotator disc 26 b . The left side front support rotator disc 24 a is sandwiched between the left side rear support rotator disc 22 a and the left side water manifold rotator disc 26 a . The left side bolt 32 a passes through slots 23 a , 25 a , and 27 a with the left side nut 30 a screwing onto the left side bolt 32 a . This applies a clamping force to the planer surfaces of the left side rear support rotator disc 22 a , left side front support rotator disc 24 a , left side water manifold rotator disc 26 a , thus restricting the rotational movements of the left side disc assembly. The right side front support rotator disc 24 b is sandwiched between right side rear support rotator disc 22 b and right side water manifold rotator disc 26 b.
Right side bolt 32 b passes through slots 23 b , 25 b , 27 b with right side nut 30 b screwing onto right side bolt 32 b thus applying clamping force to the planer surfaces of right side rear support rotator disc 22 b , right side front support rotator disc 24 b , right side water manifold rotator disc 26 b , restricting the rotational movements of right side rear support rotator disc 22 b , right side front support rotator disc 24 b , right side water manifold rotator disc 26 b securing right side rear support rotator disc 22 b , right side front support rotator disc 24 b , right side water manifold rotator disc 26 b from any movements about the planer surfaces of right side rear support rotator disc 22 b , right side front support rotator disc 24 b , right side water manifold rotator disc 26 b.
Leg 42 a and 42 b are connected at the end portion of the leg to the end portions of rear leg support connector 49 a forming a u-shape support member. The remaining end of the leg 42 a is attached securely to the outer diameter of the left side rear support rotator disc 22 a at a point opposite the slot 23 a on the left side rear support rotator disc 22 a . The remaining end of the leg 42 b is attached to the outer diameter of right side rear support rotator disc 22 b at a point opposite the slot 23 b on right side rear support rotator disc 22 b . Legs 50 a and 50 b are connected at the end portion of the leg to the end portions of front leg support connector 49 b forming a u-shape support member. The remaining end of the leg 50 a is attached securely to the outer diameter of the left side front support rotator disc 24 a at a point opposite the slot 25 a on the left side front support rotator disc 24 a . The remaining end of the leg 50 b is attached to the outer diameter of the right side front support rotator disc 24 b at a point opposite the slot 25 b on right side front support rotator disc 24 b.
Left side rear support leg adjuster tube 44 a is permanently attached to the left side rear support leg 42 a , facing out at the lower portion of the left side rear support leg 42 a . Left side rear support adjuster leg 48 a is inserted through the left side rear support leg adjusted tube 44 a . The diameter of the left side rear support adjuster leg 48 a is sufficiently smaller in diameter than the diameter of the left side rear support leg adjuster tube 44 a . This allows the left side rear support leg adjuster 44 a to move freely in the left side rear support leg adjuster tube 44 a.
When the left side rear support adjuster leg 48 a is positioned where it is in the correct location the locking device 46 a locks the left side rear support adjuster leg 48 a in place. Right side rear support leg adjuster tube 44 b is permanently attached to the right side rear support leg 42 b , facing out at the lower portion of the right side rear support leg 42 b . Right side rear support adjuster leg 48 b is inserted through the right side rear support leg adjuster tube 44 b . The diameter of the right side rear support adjuster leg 48 b is sufficiently smaller in diameter than the diameter of the right side rear support leg adjuster tube 44 b . This allows the right side rear support leg adjuster 48 b to move freely in the right side rear support leg adjuster tube 44 b . When the right side rear support adjuster leg 48 b is positioned where it is in the correct location the locking device 46 b locks the right side rear support adjuster leg 44 b in place. Right side front support leg adjuster tube 51 b is permanently attached to the right side front support leg adjuster 53 b , facing out at the lower portion of the right side front support leg 50 b . Right side front support leg adjuster 53 b is inserted through the right side front support leg adjuster tube 51 b . The diameter of the right side front support leg adjuster 53 b is sufficiently smaller in diameter than the diameter of the right side front support leg adjuster tube 51 b . This allows the right side front support leg adjuster 53 b to move freely in the right side front support leg adjuster tube 51 b.
When the right side front support leg adjuster 53 b is positioned where it is in the correct location the locking device 52 b locks the right side front support leg adjuster 53 b in place. Left side front support leg adjuster tube 51 a is permanently attached to the left side front support leg adjuster 53 a , facing out at the lower portion of the left side front support leg 50 a . Left side front support leg adjuster 53 a is inserted through the left side front support leg adjuster tube 51 a . The diameter of the left side front support leg adjuster 53 a is sufficiently smaller in diameter than the diameter of the left side front support leg adjuster tube 51 a . This allows the left side front support leg adjuster 53 a to move freely in the left side front support leg adjuster tube 51 a . When the left side front support leg adjuster 53 a is positioned where it is in the correct Location the locking device 52 a locks the right side front support leg adjuster 53 a in place.
The fire protection sprinkler system water manifold of the present invention is illustrated in FIG. 3 . The left side water manifold rotator disc 26 a is showing the left side water manifold rotator disc slot 27 a near the outer edge of the planer surface of the left side water manifold rotator disc 26 a . The right side water manifold rotator disc 26 b is showing the right side water manifold rotator disc slot 27 b near the outer edge of the planer surface of the right side water manifold rotator disc 26 b The water manifold sprinkler assembly connector tee 40 is secured to the water manifold 20 facilitating the attachment of the sprinkler head assembly 34 .
A perspective view is illustrated in FIG. 6 showing a multitude of Fire Protection Systems 18 attached to the roof of a house 54 with a spray of water 55 emitting from the spray heads of the fire protection sprinkler systems 18 .
Accordingly, the reader will see that the fire protection system of this invention can be used conveniently, inexpensively and can be set up quickly. It can be made of different materials. It can be made using different dimensions, such as, making it taller, shorter, wider, narrower, lighter, heavier, or in whatever configurations not stated. It allows for an easy and quick setup in emergency situations. Although the description above contains much specificity, these should not be construed as limiting the scope of the invention, but as merely providing illustrations of some of the presently preferred embodiments of this invention. For example, the water delivery system can range from the standard tap water supply to a pressurized, electronically controlled, or a liquid filled tank system. Thus, the scope of the invention should be determined by the appended claims and their legal equivalents, rather than by the examples given. | A fire protection system has a plurality of sprinkler assemblies connected together in series. Each sprinkler assembly has a water manifold pipe, a pair of U-shaped supports, and a sprinkler head connected to the water manifold pipe. Each U-shaped support has a pair of legs with support rotator discs affixed to upper ends of the legs for pivotally connecting the U-shaped supports to the water manifold pipe. The manifold pipe extends through manifold rotator discs affixed thereto. Locking bolts extends through respective semi-circular slots formed in the rotator discs of the U-shaped supports and the manifold rotator discs for locking the U-shaped supports in a selected pivotal angle of adjustment. During use, the support legs of the front and rear U-shaped supports are supported by front and rear roof sections of a house with the apex of the roof extending between the pair of U-shaped supports. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an impact drill for use in a drilling operation on a concrete, mortar or tile, for example, and more particularly to an impact drill having a drill mode for performing a drilling operation by rotating a drill bit and an impact drill mode for performing a drilling operation by rotating and vibrating the drill bit.
2. Description of the Related Art
FIG. 1 shows a conventional example of the impact drill of this kind. In FIG. 1 , reference numeral 1 denotes a main frame portion that forms an outer shell of the impact drill and has the self-contained parts at predetermined positions, comprising a gear cover 17 , an inner cover 18 , an outer cover 19 , a housing 7 and a handle portion 6 . Reference numeral 2 denotes a spindle inserted transversely through the gear cover 17 , and 3 denotes a drill chuck attached at the top end of the spindle. A rotational ratchet 4 is mounted near the central part of the spindle 2 . The rotational ratchet 4 is rotated along with the rotation of the spindle 2 , and moved along with the axial movement of the spindle 2 . The serrated irregularities are formed on one face 4 a of the rotational ratchet 4 .
Reference numeral 5 denotes a stationary ratchet disposed at a position opposed to the rotational ratchet 4 , in which the serrated irregularities are also formed on one face 5 a of the stationary ratchet. The stationary ratchet 5 has a hollow cylindrical shape, and is fixed to the inner cover 18 , irrespective of the rotation and axial movement of the spindle 2 .
On the other hand, a motor 8 is disposed inside the housing 7 linked to the handle portion 6 . A rotational driving force of the motor 8 is transmitted via a rotation shaft 9 to a gear 10 . Since the gear 10 is press fit into a second pinion 11 , the rotational driving force is transmitted to the second pinion 11 . The second pinion 11 has two pinion portions 11 a , 11 b having a different number of teeth, which are engaged with a low speed gear 12 and a high speed gear 13 , respectively. When the second pinion 11 is rotated, both the gears 12 , 13 are also rotated.
Reference numeral 14 denotes a clutch disk engaged with the spindle 2 and mounted to be slidable in the axial direction. If the clutch disk 14 is inserted into a concave portion of the low speed gear 12 , the rotation of the second pinion 11 is transmitted via the low speed gear 12 and the clutch disk 14 to the spindle 2 , as shown in FIG. 1 . On the other hand, if the clutch disk 14 is slid to the right from the position of FIG. 1 , and inserted into a concave portion of the high speed gear 13 , the rotation of the second pinion 11 is transmitted via the high speed gear 13 and the clutch disk 14 to the spindle 2 . Accordingly, the spindle 2 can be rotated at low speed or high speed by movement of the clutch disk 14 .
Reference numeral 15 denotes a change lever for changing the operation mode of the impact drill, namely, between a drill mode and an impact drill mode. A change shaft 16 is press fit into the change lever 15 , whereby when the change lever 15 is rotated, the change shaft 16 is also rotated. The change shaft 16 has a notch portion 16 a , as shown in FIGS. 2 , 3 and 4 , whereby when the notch portion 16 a is at the position of FIG. 2 , the impact drill is operated in the drill mode, while when the notch portion 16 a is at the position of FIG. 3 , the impact drill is operated in the impact drill mode.
(A) Drill Mode
When a drill bit (not shown) attached in the drill chuck 3 is contacted with a machined surface and the handle portion 6 is pressed in a direction of the arrow in FIG. 1 , an end part of the spindle 2 makes contact with the change shaft 16 to be immovable to the right, when the notch portion 16 a of the change shaft 16 is at the position of FIG. 2 . Accordingly, there is no contact between the irregular face 4 a of the rotational ratchet 4 and the irregular face 5 a of the stationary ratchet 5 . Accordingly, a rotational driving force of the motor 8 is transmitted via the low speed gear 12 or high speed gear 13 to the spindle, so that the drill bit is given a rotational force.
(B) Impact Drill Mode
In an impact drill mode, the notch portion 16 a of the change shaft 16 is brought into the position of FIG. 3 by rotating the change lever 15 . Then, the drill bit attached in the drill chuck 3 is contacted with a machined surface. If the handle portion 6 is pushed in a direction of the arrow in FIG. 1 , an end part of the spindle 2 enters the notch portion 16 a , as shown in FIG. 4 . That is, the spindle 2 is slightly moved to the right, so that the irregular face 4 a of the rotational ratchet 4 is contacted with the irregular face of the stationary ratchet 5 .
In drilling the machined surface, if the spindle 2 is rotated in the state of FIG. 4 , the rotational ratchet 4 is meshed and engaged with the stationary ratchet 5 , and rotated to cause vibration due to the irregular faces of both the ratchets 4 and 5 . This vibration is transmitted through the spindle 2 to the drill bit (not shown). That is, the drill bit is given a rotational force and vibration to perform a drilling operation.
However, when the impact drill is operated in the impact drill mode, the vibration caused by rotation of the spindle in the state where the irregular faces of the ratchets 4 and 5 are contacted under pressure is transmitted not only to the drill bit, but also through the stationary ratchet 5 and the inner cover 18 from the housing 7 to the handle portion 6 . Therefore, there is a problem that the user of the impact drill undergoes a great vibration, and feels uncomfortable. Especially when the impact drill is continuously employed for a long time, care must be taken not to transmit the vibration to the user and cause adverse effect on the health of the user.
Several proposals for reducing the vibration transmitted to the user have been made. For example, in JP-UM-B-2-30169, a structure was disclosed in which a clutch cam 22 is supported movably in the axial direction of the spindle 20 , and pressed and urged to a rotary cam 21 by a spring 23 , as shown in FIG. 5 . In FIG. 5 , reference numeral 21 denotes a rotary cam that is rotated along with the spindle 20 . A cam face 21 a of the rotary cam 21 is formed with serrated irregularities.
On the other hand, the clutch cam 22 is composed of a hollow cylindrical portion slidable in the axial direction of the spindle 20 and a flange portion 22 b . A cam face 22 c of the flange portion 22 b is formed with a serrated irregular face.
The spring 23 is provided between the flange 22 b of the clutch cam 22 and a plate 24 a engaging a groove 22 a of the clutch cam 22 , and always urges the clutch cam 22 toward the rotary cam 21 . Thus, when the spindle 20 is moved backward, the cam faces 21 a and 22 c are contacted under pressure. If a pressing force applied to the spindle 20 overcomes a resilient force of the spring 23 , the spring 23 is compressed, so that the clutch cam 22 is moved backward (to the right in the figure). When the clutch cam 22 is moved forward from the back position due to a resilient force of the spring 23 , it strikes against the rotary cam 21 , so that the rotary cam 21 is vibrated together with the spindle 20 .
With this structure, since the vibration caused by contact between the cam faces 21 a and 22 c is relieved by the spring 23 and transmitted to the handle portion (not shown), there is the effect that the vibration transmitted to the user is reduced as compared with the structure in which the ratchet 5 is firmly disposed as shown in FIG. 1 .
On the other hand, FIGS. 6 and 7 are schematic views showing the above structure in which the change shaft 16 and the change lever 15 as shown in FIGS. 2 , 3 and 4 are disposed at the right end portion of the spindle 20 as shown in FIG. 5 . In FIGS. 6 and 7 , a spring 25 is additionally inserted between the rotary cam 21 and the plate 24 a to prevent the spindle 20 from being moved to the right.
When the notch portion 16 a of the change shaft 16 is at the position as shown in FIG. 6 , the impact drill is operated in the drill mode in which the cam faces 21 a and 22 c are always out of contact. Also, when the notch portion 16 a of the change shaft 16 is at the position as shown in FIG. 7 , the impact drill is operated in the impact drill mode in which the cam faces 21 a and 22 c are contacted and collided.
In this impact drill mode, if a pressing force is applied to the main body (not shown), the spindle 20 is moved to the right. However, when the pressing force is weak, a right end portion of the spindle 20 slightly enters the notch portion 16 a , and the cam faces 21 a and 22 c of FIG. 7 are lightly contacted, so that the back movement amount of the clutch cam 22 is small, the restoring force of the spring 23 is small, and a stroke force from the clutch cam 22 to the rotary cam 21 is reduced.
On the other hand, when the pressing force is strong, a right end portion of the spindle 20 deeply enters the notch portion 16 a , and the cam faces 21 a and 22 c are greatly engaged, so that the clutch cam 22 is greatly moved backward, whereby the restoring force of the spring 23 is great, and the stroke force from the clutch cam 22 to the rotary cam 21 is significant.
Herein, when an object to be drilled which is hard and thin tile or concrete is positioned for drilling, or drilled prudently, it is necessary to sustain a state where the pressing force is weakened to suppress the stroke force, as described above. Several proposals have been conventionally made for the structure in which the magnitude of stroke force is adjustable.
In Japanese Patent No. 3002284, the maximal movement amount of the rotational ratchet and the spindle is made larger than engageable with the stationary ratchet, in which the stationary ratchet is provided movably in the axial direction, and biased forward by the spring. A biasing force of the spring is adjusted by changing a force for pressing the main body.
In JP-A-62-74582, there was described an impact drill in which the rotational ratchet and the spindle can not be moved in the axial direction, and the stationary ratchet is provided movably in the axial direction, and biased forward by the spring, whereby a member for regulating the axial movement of the stationary ratchet is provided adjustably from the outside. The stationary ratchet is regulated from moving forward beyond a predetermined position by adjusting the regulating member, so that the intermeshing depth of ratchets is adjusted.
In Japanese Patent No. 2754047, there was described an impact drill in which the rotational ratchet and the spindle can not be moved in the axial direction, and the stationary ratchet is provided movably in the axial direction, and biased forward by the spring, whereby a second spring for adjusting the compression amount from the outside is provided, in addition to a first spring for always biasing the stationary ratchet. By adjusting the compression amount from the outside, a combination of the first spring and the second spring is varied to adjust the biasing force of the spring.
In JP-A-3-178708, there was described an impact drill in which the rotational ratchet and the spindle are provided to be movable backward to the position at which they are engaged with the stationary ratchet, and the stationary ratchet is provided movably in the axial direction, and biased forward by the spring, whereby the axial position of a spring seat is provided adjustably from the outside. The biasing force of the spring is adjusted by moving the spring seat from the outside. Also, there was described a similar impact drill in which the length of an outer frame itself is provided adjustably. In this case, the biasing force of the spring is adjusted by changing the length of the outer frame itself.
In JP-A-4-240010, there was described an impact drill in which the rotational ratchet and the spindle are provided to be movable backward to the position at which they are engaged with the stationary ratchet, and the stationary ratchet is provided movably in the axial direction, and biased forward by the spring, whereby the axial position of a seat accepting the spring from behind is provided adjustably from the outside. The biasing force of the spring is adjusted by changing the axial position of the seat accepting the spring from behind.
SUMMARY OF THE INVENTION
In Japanese Patent No. 3,002,284, it is difficult to keep the pressing force constant, and particularly when a small stroke force is attained by the weak pressing force, the stroke force is too excessive if the pressing force is too strong, resulting in a problem that the fragile partner member is possibly broken.
In JP-A-62-74582 the vibration transmitted from the spindle to the housing is not relieved, and the intermeshing depth of ratchets may be reduced but the relative position of the ratchet and the spring is invariable, resulting in a problem that the biasing force of the spring can not be weakened. Likewise, with this constitution, the intermeshing depth of ratchets may be increased, but the relative position of the ratchet and the spring is invariable, whereby the biasing force of the spring could not be increased. That is, with this constitution, the intermeshing depth of ratchets may be changed but the relative position of the ratchet and the spring is invariable, resulting in a problem that the adjustment width of the stroke force is small.
In Japanese Patent No. 2754047, JP-A-3-178708, and JP-A-4-240010, the vibration transmitted from the spindle to the housing is not relieved, and the biasing force of the spring may be changed but the intermeshing depth of ratchets may not be changed, resulting in a problem that the adjustment width of the stroke force is small.
It is an object of the invention to provide an impact drill that solves the above-mentioned problems associated with the prior art. It is a further object of the invention to provide an impact drill in which a state of generating a set stroke force is maintained even if the biasing force is excessive, the adjustment width of the stroke force is large, and the vibration transmitted to the user is reduced.
According to one aspect of the invention, there is provided with an impact drill including: a spindle rotated by a motor and movable in an axial direction; a drill chuck fixed to the spindle and mountable with a drill bit; a first ratchet fixed to the spindle and having a face of an irregular portion; a second ratchet having a face of an irregular portion opposed to the face of the irregular portion of the first ratchet and movable in the axial direction but unrotatable; and a spring for urging the second ratchet in a direction of the first ratchet, in which the spindle is given an axial vibration by a contact and separation action between the irregular faces of the first and second ratchets due to a relative rotation of the first ratchet to the second ratchet, wherein a regulating member regulates an amount of movement of the spindle at a plurality of positions in a range where the first and second ratchets can be engaged.
According to another aspect of the invention, the regulating member is movable relative to a main frame portion to come into contact with the spindle. The regulating member is formed to gradually change an interval between the spindle and the regulating member, when the regulating member is moved relative to the main frame portion.
According to another aspect of the invention, the regulating member has a columnar shape. The regulating member has a plurality of notch portions having a different distance from a center of the regulating. The regulating member is rotatably provided in the main frame portion so as to make the notch portions contactable with the spindle.
According to another aspect of the invention, the regulating member has a plate-like shape. The regulating member has a plurality of step portions having a different depth. The regulating member is movably provided in the main frame portion so as to make the step portions contactable with the spindle.
According to another aspect of the invention, the movement amount of the spindle movable in the axial direction is regulated to be a minimum value (as a first mode). The movement amount of the spindle movable in the axial direction is regulated to be a middle value (as a second mode). The movement amount of the spindle movable in the axial direction is regulated to be a maximum value (as a third mode).
According to another aspect of the invention, the first mode is a mode of regulating the movement amount of the spindle to an extent that the irregular portion of the first ratchet and the irregular portion of the second ratchet are contacted with each other. The second mode is a mode of regulating the movement amount of the spindle to an extent that the irregular portion of the first ratchet and the irregular portion of the second ratchet are engaged with each other at a bottom portion of the first ratchet and the second ratchet. The third mode is a mode of regulating the movement amount of the spindle to an extent that the irregular portion of the first ratchet and the irregular portion of the second ratchet are engaged with each other to a bottom portion of the first ratchet and the second ratchet. The second ratchet is further moved backward by pressing a main frame of the impact drill onto a workpiece.
According to another aspect of the invention, a fourth mode of regulating the movement amount of the spindle to an extent that the irregular portion of the first ratchet and the irregular portion of the second ratchet are not contacted with each other.
Since the amount of back movement of the spindle and the rotational ratchet is regulated, the work may be performed with such a pressing force that the spindle comes into contact with the regulating member, whereby even though the pressing force is further increased, the compression amount of the spring is not increased, and the biasing force of the spring is not increased, so that the stroke force does not become excessive to prevent the partner member from being broken.
When the stroke force is weakened, the amount of back movement of the spindle and the rotational ratchet is regulated to be smaller, whereby the intermeshing depth of ratchets is not only shallower, but also the compression amount of the spring is reduced, so that the biasing force of the spring can be weakened. Accordingly, the stroke force can be weaker than conventionally, and therefore made adequate for the fragile partner member.
Moreover, when the stroke force is intensified, the amount of back movement of the spindle and the rotational ratchet is regulated to be larger, whereby the intermeshing depth of ratchets is not only deeper, but also the compression amount of the spring is increased, so that the biasing force of the spring can be intensified. Accordingly, the stroke force can be stronger than conventionally, and therefore made adequate for the partner member difficult to be drilled.
If the work is performed with such a pressing force that the spindle does not come into contact with the regulating member, the vibration of the spindle in the axial direction is relieved and transmitted via the ratchet and the spring to the outer frame portion, whereby the operator performs the work comfortably with less vibration transmitted to the operator.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a cross-sectional view showing one example of the conventional impact drill;
FIG. 2 is an explanatory view of the impact drill in a drill mode;
FIG. 3 is an explanatory view of the impact drill in an impact drill mode;
FIG. 4 is an explanatory view of the impact drill in the impact drill mode;
FIG. 5 is a partial constitutional view showing another example of the conventional impact drill;
FIG. 6 is an explanatory view of another example of the conventional impact drill in the drill mode;
FIG. 7 is an explanatory view of another example of the conventional impact drill in the impact drill mode;
FIG. 8 is a cross-sectional view showing an impact drill according to a first embodiment of the invention, in the drill mode;
FIG. 9 is a cross-sectional view showing the impact drill according to the first embodiment of the invention, in a weak stroke mode;
FIG. 10 is a cross-sectional view showing the impact drill according to the first embodiment of the invention, in a strong stroke mode;
FIG. 11 is a cross-sectional view showing the impact drill according to the first embodiment of the invention, in a stroke force variable mode;
FIG. 12 is a cross-sectional view showing an impact drill according to a second embodiment of the invention, in the drill mode;
FIG. 13 is a cross-sectional view showing the impact drill according to the second embodiment of the invention, in the weak stroke mode;
FIG. 14 is a cross-sectional view showing the impact drill according to the second embodiment of the invention, in the strong stroke mode;
FIG. 15 is a cross-sectional view showing the impact drill according to the second embodiment of the invention, in the stroke force variable mode;
FIG. 16 is an explanatory view of a change shaft of the impact drill according to the first embodiment of the invention; and
FIG. 17 is an explanatory view of a plate-like change lever of the impact drill according to the second embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The preferred embodiments of the present invention will be described below in detail.
First Embodiment
FIGS. 8 , 9 , 10 and 11 are constitutional views of a main portion of an impact drill according to a first embodiment of the invention. Firstly, referring to FIG. 8 , the constitution of each part will be described below.
A spindle 102 is provided in a main frame portion 101 and moved forward (to the left in the figure) or backward (to the right in the figure) relative to a workpiece 119 . A chuck 103 for mounting a drill bit 118 is provided at the top end of the spindle 102 . A first ratchet 104 and a second ratchet 105 are provided in the almost central part of the main frame portion 101 . The first ratchet 104 is rotated along with the spindle 102 and moved axially, and has serrated irregularities 104 a on one face. The second ratchet 105 is formed with serrated irregularities 105 d on a bottom portion 105 c . Also, the second ratchet 105 has a dual cylindrical shape, in which an inner cylindrical portion 105 a slides on the spindle 102 and an outer cylindrical portion 105 b slides in the axial direction of the spindle 102 along an inner wall of the main frame portion 101 , but has a notch portion in a part on the circumferential face to prevent rotational motion.
Moreover, a side wall portion 122 extends in a direction of the spindle inside the main frame portion 101 , and a spring 120 is provided between the side wall portion 122 and the cylindrical bottom portion 105 c . Reference numeral 109 denotes a rotation shaft to which a rotational driving force is transmitted from a motor (not shown), in which its rotational driving force is transmitted via a gear 110 to a second pinion 111 . Reference numeral 112 denotes a low speed gear, 113 denotes a high speed gear, and 114 denotes a clutch disk, in which when the clutch disk 114 is at the position as shown, a rotational force is transmitted via the low speed gear 112 to the spindle 102 .
On the other hand, if the clutch disk 114 is rotated to the position where the high speed gear 113 and the spindle 102 are engaged by rotating a change lever 117 , a rotational force of the second pinion 111 is transmitted via the high speed gear 113 to the spindle 102 . Accordingly, the spindle 102 can be rotated at low speed or high speed depending on the rotated position of the change lever 117 .
As a result of the experiment, it has been confirmed that the vibration transmitted to the user in the drilling operation, namely, the vibration of an impact drill main body, is reduced owing to the above configuration.
According to first embodiment of the invention, a steel ball 125 is provided at a rear end of the spindle 102 , and contacted with a columnar change shaft 141 having a plurality of notch portions different in the depth. FIG. 16 shows a sectional face of the change shaft 141 taken along the A—A plane of FIG. 8 . In this example, there are a face 141 a having the largest notch depth W 3 , a face 141 b having the next largest notch depth W 2 , a face 141 c having the smallest notch depth W 1 , and a columnar face 141 d without notch. This change shaft 141 is engaged with a change lever 140 , and the contact face with the steel ball 125 is changed in the order of 141 a , 141 b , 141 c and 141 d by rotating the change lever 140 .
The operation of the impact drill with the above constitution will be described below.
(a) Drill Mode
A drill mode is shown in FIG. 8 . That is, the change shaft 141 is rotated by turning the change lever 140 , so that the steel ball 125 disposed at the rear end of the spindle 102 is contacted with a part of the change shaft 141 without notch portion 142 , namely, the face 141 d of FIG. 16 . In this positional relation, even when the main frame portion 101 is pressed in the direction of the arrow, a serrated irregular portion 104 a of the first ratchet 104 and a serrated irregular portion 105 d of the second ratchet 105 are not engaged, causing no vibration, whereby the impact drill is operated as the normal drill mode.
(b) Weak Stroke Impact Drill Mode
FIG. 9 shows a weak stroke mode of the impact drill. By turning the change lever 140 from the state of FIG. 8 , the steel ball 125 at the rear end of the spindle 102 is contacted with the face 141 c of the change shaft 141 having the smallest notch depth W 1 . This notch depth W 1 is regulating the movement of the spindle 102 to the extent that the serrated irregular portion 104 a of the first ratchet 104 and the serrated irregular portion 105 d of the second ratchet 105 are lightly contacted at the tip. In this positional relation, even when the main frame portion 101 is pressed with a great force in the direction of the arrow, the restoring force of the spring 120 is small, and the impact force occurring between the first ratchet 104 and the second ratchet 105 is small. Accordingly, when this small impact force is sustained, this weak stroke mode is advantageous in prudently drilling the hard, thin tile or the like.
(c) Strong Stroke Impact Drill Mode
FIG. 10 shows a strong stroke mode of the impact drill. By further turning the change lever 140 from the state of FIG. 9 , the steel ball 125 at the rear end of the spindle 102 is contacted with the face 141 b of the change shaft 141 having the larger notch depth W 2 . This notch depth W 2 is regulating the movement of the spindle 102 to the extent that the serrated irregular portion 104 a of the first ratchet 104 and the serrated irregular portion 105 d of the second ratchet 105 are engaged to the bottom. Thus, the second ratchet 105 is moved further backward from the position of FIG. 9 , the restoring force of the spring 120 is great, and the impact force occurring between the first ratchet 104 and the second ratchet 105 is great. Accordingly, when this great impact force is sustained, this strong stroke mode is optimal in prudently drilling the mortar wall or the like at high drilling speed.
(d) Stroke Force Variable Impact Drill Mode
FIG. 11 shows a stroke force variable mode of the impact drill. By further turning the change lever 140 from the state of FIG. 10 , the steel ball 125 at the rear end of the spindle 102 is opposed to the face 141 a of the change shaft 141 having the largest notch depth W 3 . This notch depth W 3 is regulating the movement of the spindle 102 to the extent that the serrated irregular portion 104 a of the first ratchet 104 and the serrated irregular portion 105 d of the second ratchet 105 are engaged to the bottom, the main frame portion 101 is further pressed in a direction of the arrow, and the rear end 105 e of the second ratchet 105 does not abut against a main extension frame 122 even when the second ratchet 105 is moved backward. In this positional relation, when the main frame portion 101 is pressed according to the feeling of the operator himself or herself, the restoring force of the spring 120 is similarly changed depending on the magnitude of pressing force, whereby the operator can perform the operation by adjusting the magnitude of stroke force according to the force of pressing the main frame portion 101 .
As described above, with the first embodiment, the change lever 140 is rotated by changing the face of the change shaft 141 in contact with the steel ball 125 , whereby vibration modes for various stroke forces can be implemented.
Second Embodiment
FIG. 12 shows a second embodiment of the invention, which has one feature in that the steel ball 125 provided at a rear end of the spindle 102 is contacted with a plate-like change lever 143 having the step portions different in the depth.
That is, FIG. 17 shows the plate-like change lever 143 in enlargement, which has a face 143 a having the largest step W 3 , a face 143 b having the next largest step W 2 , a face 143 c having the smallest step W 1 , and a face 143 d without step. This plate-like change lever 143 is provided movably in the vertical direction, whereby the contact face with the steel ball 125 is changed in accordance with its position. FIGS. 12 to 15 are cross-sectional views of the impact drill as looked from the above (opposite to the side where the handle portion 6 is provided in FIG. 1 ). Accordingly, since the change lever 143 is provided movably in the left-to-right direction of the impact drill, one end of the change lever 143 can be pressed by a forefinger, and the other end pressed by a thumb, when the handle portion 6 is grasped, whereby the operability is excellent.
(a) Drill Mode
A drill mode is shown in FIG. 12 . That is, the face 143 d without step of the plate-like change lever 143 is contacted with the steel ball 125 . In this positional relation, even when the main frame portion 101 is pressed in the direction of the arrow, a serrated irregular portion 104 a of the first ratchet 104 and a serrated irregular portion 105 d of the second ratchet 105 are not engaged, causing no vibration, whereby the impact drill is operated as the normal drill mode.
(b) Weak Stroke Impact Drill Mode
FIG. 13 shows a weak stroke mode of the impact drill. By pressing down the plate-like change lever 143 from the state of FIG. 12 , the steel ball 125 is contacted with the face 143 c having the smallest step W 1 . This step W 1 has the depth of regulating the movement of the spindle 102 to the extent that the serrated irregular portion 104 a of the first ratchet 104 and the serrated irregular portion 105 d of the second ratchet 105 are lightly contacted at the tip. In this positional relation, even when the main frame portion 101 is pressed with a great force in the direction of the arrow, the restoring force of the spring 120 is small, and the impact force occurring between the first ratchet 104 and the second ratchet 105 is small.
(c) Strong Stroke Impact Drill Mode
FIG. 14 shows a strong stroke mode of the impact drill. By further pressing down the plate-like change lever 143 from the state of FIG. 13 , the steel ball 125 is contacted with the face 143 b having the step W 2 . This step W 2 has the depth of regulating the movement of the spindle 102 to the extent that the serrated irregular portion 104 a of the first ratchet 104 and the serrated irregular portion 105 d of the second ratchet 105 are engaged to the bottom. Thus, the second ratchet 105 is moved further backward from the position of FIG. 9 , the restoring force of the spring 120 is great, and the impact force occurring between the first ratchet 104 and the second ratchet 105 is great.
(d) Stroke Force Variable Impact Drill Mode
FIG. 15 shows a stroke force variable mode of the impact drill. By further pressing down the plate-like change lever 143 from the state of FIG. 14 , the steel ball 125 is contacted with the face 143 a having the largest step W 3 . This step W 3 has the depth of regulating the movement of the spindle 102 to the extent that the serrated irregular portion 104 a of the first ratchet 104 and the serrated irregular portion 105 d of the second ratchet 105 are engaged to the bottom, the main frame portion 101 is further pressed in a direction of the arrow, and the rear end 105 e of the second ratchet 105 does not abut against a main extension frame 122 even when the second ratchet 105 is moved backward. In this positional relation, when the main frame portion 101 is pressed according to the feeling of the operator himself or herself, the restoring force of the spring 120 is similarly changed depending on the magnitude of pressing force, whereby the operator can perform the operation by adjusting the magnitude of stroke force according to the force of pressing the main frame portion 101 . | An impact drill includes a first ratchet rotating along with a spindle and movable in an axial direction, a second ratchet engaged with the first ratchet and movable in a axial direction but unrotatable, and a spring provided between the second ratchet and a partial member of a housing. An amount of movement of the spindle in the axial direction is regulated, so that the pressing force is too excessive, the restoring force of the spring urging the second ratchet is controlled to maintain a state of generating a set stroke force. | 1 |
This is a continuation of co-pending application Ser. No. 757,226 filed on July 22, 1985, now abandoned.
FIELD OF THE INVENTION
The invention relates to Mannich basis of spirosuccinimides having anticonvulsant, sedative and/or antileukemic properties.
BACKGROUND OF THE INVENTION
The ability of spirosuccinimides to alter the excitability of conductive tissues as anticonvulsants, local anesthetics and antiarrhythmics has been reported. Hauck, et al, J. Med. Chem., 10, 611 (1967); Tenthorey, et al, J. Med. Chem., 24, 47 (1981); Alvin, et al, Anticonvulsants, (J. A. Vida, Ed.), p. 112, Academic Press (1977).
Mannich bases of spiro-5'-oxazolidine-2,4'-dione are disclosed in J. Heterocyclic Chem., 20, 13 (1983). Mannich bases of spiro[fluorene-9,3'-pyrrolidine]-2,40 ,5'-dione having purported anticonvulsant and antileukemic activity are reported in J. Pharmaceutical Sci., 67, 953 (1978); Heterocycles, 12, 637 (1979); and Pharmazie, 34, 581 (1979).
Various N-substituted azaspirane-diones are disclosed in the following U.S. Pat. Nos: 3,106,552; 3,150,143; 3,200,118; 3,238,217; 3,256,276; 3,257,398; 3,263,862, 3,507,881. Despite the broad generic teachings of these patents, the present spirosuccinimides are readily distinguished as Mannich bases. They contain only a single carbon atom between the azaspirane-dione nitrogen and the amino nitrogen of the substituent side chain. The presence of the methylene unit gives the present compounds unique chemical properties over compounds which are not Mannich bases.
SUMMARY OF THE INVENTION
Compounds of the formula ##STR2## are provided wherein ring A is selected from the group consisting of saturated and unsaturated monocyclic and bicyclic carbon rings of at least 5 carbon atoms. R and R 1 are each selected from the group consisting of lower alkyl, lower alkenyl, cycloalkyl and aryl groups, and when R and R 1 are taken together with the nitrogen atom to which they are attached, represent a heterocyclic selected from the group consisting of morpholino, piperidino, pyrrolidino, piperazino and lower alkyl-, lower hydroxyalkyl-, lower haloalkyl-, lower haloalkoxy-, aryl-, haloaryl-, pyridyl-, and arylakyl-substituted derivatives of these heterocyclic groups.
The compounds of the present invention may be taken up in pharmaceutically acceptable carriers, for example, solutions, suspensions, tablets, capsules, ointments, elixers, and injectable compositions and the like. The compositions may be particularly employed as sedatives, and to protect against convulsions.
In a preferred embodiment, ring A comprises a cyclopentyl or cyclohexyl ring. In another preferred embodiment, ring A is an indanyl or indenyl ring.
It is an object of the invention to provide novel, physiologically active compounds and methods for their preparation.
It is an object of the invention to provide novel compounds which are Mannich bases of spirosuccinimides having anticonvulsant, sedative or antileukkemic properties.
It is an object of the invention to provide compositions of these novel compounds in pharmaceutically acceptable carriers for use as anticonvulsants, sedatives and antileukemics.
It is an object of the invention to provide a method of sedation.
Other objects and advantages of the invention will appear hereinafter.
DESCRIPTION OF THE FIGURE
FIG. 1 shows the protection of mice against seizures induced by Maximl Electroshock (MES, 50 mA, 0.2 sec.) and pentylenetetrazole, available as "METRAZOLE", (scMet, 85 mg/kg) by a series of indanylspirosuccinimide Mannich bases. Candidate compounds were administered intraperitoneally thirty minutes prior to seizure challenge to at least 5 animals per dose.
FIG. 2 shows the protection of mice against MES as a function of dose and time for a representative compound of the present invention, 1'-[methyl(N-hydroxyethyl)piperazino]-indan-1-spiro-3'-pyrrolidine-2',5'-dione.
DESCRIPTION OF THE INVENTION
The preferred method for preparing the compounds of the present invention comprises reacting the parent spiroimide with formaldehyde and an appropriate secondary amine under Mannich reaction conditions. The Mannich bases thus prepared have demonstrated anticonvulsant activity in a standard phamacological assay using pentylenetetrazole and/or electroshock as the convulsant agent.
Compounds of formula (I) were prepared as follows. 0.25 moles of the parent ketone were condensed with 0.45 moles of ethyl cyanoacetate in benzene and acetic acid, with ammonium acetate as a catalyst, and refluxed for 18 h under standard Knoevenagel conditions. The condensation product, once isolated and purified, was stirred at room temperature for 4 days in an aqueous ethanolic solution with 2.5 molar equivalents of KCN to yield the dicyano ester. The latter was hydrolyzed and decarboxylated, without prior purification, by refluxing in aqueous HCl/acetic acid for 2 days. Basification with 20% NaOH, heating with activated charcoal, filtration and re-acidification with 5.5M HCl afforded the corresponding diacid. Cyclization of the diacid to its corresponding anhydride was accomplished by refluxing in acetyl chloride for 3 h, removal of the solvent under reduced pressure, and recrystallization of the products from hot benzene. Ammonolysis of the cyclic anhydride in benzene/ether (2.5:1.0) gave the corresponding amido acid which was cyclized in refluxing acetyl chloride, to yield the spiroimide which was recrystallized from hot ethanol/ether. Three molar equivalents of a secondary amine from Table 1 or 2 to one equivalent of imide were mixed thoroughly in a flask contained in an ice bath. To this was added 3 molar equivalents of aqueous formaldehyde with vigorous stirring. The solids thus derived were recrystallized from hot benzene/petroleum ether (1:1).
In a preferred embodiment according to formula (I), ring A is selected from the group of cyclopentyl, cyclohexyl, indanyl and indenyl groups; R and R' form, together with the nitrogen to which they are attached, a heterocyclic ring selected from the group consisting of morpholino, piperidino, N-methyl-piperazino, N-(p-chlorophenyl)piperazino N-hydroxyethylpiperazino and N-(2'-pyridyl)-piperazino; or R and R' are each benzyl groups. Preferred spiroindanylsuccinimides include 1'-methylmorpholino-indan-1-spiro-3'-pyrrolidine-2',5'-dione; 1'-methylpiperidinoindan-1-spiro-3'-pyrrolidine-2',5'-dione; 1'-[methyl-N-(4-chlorophenyl)piperazino]-indan-1-spiro-3'-pyrrolidine-2',5'-dione; 1'-[methyl-(N-methyl)piperazino]-indan-1-spiro-3'-pyrrolidine-2',5'-dione; 1'-[methyl(N-hydroxyethyl)piperazino]-indan-1-spiro-3'-pyrrolidine-2',5'-dione; and 1'-[methyl(N-2"pyridyl)piperazino]-indan-3'-pyrrolidine-2',5'-dione. Preferred spirocylopentylsuccinimides include N-methyl-morpholino-2-azaspiro[4.4]nonane-1,3-dione; N-methyl-(N-methyl)piperazino-2-azaspiro[4.4]-nonane-1,3-dione; and N-methyl(N-phenyl)piperazino-2-azaspiro[4.4]-nonane-1,3-dione.
The physical and spectral properties of nine compounds prepared according to the above procedure from the parent ketones indanone and cyclopentanone are set forth in Tables 1 and 2, respectively. All compounds had correct mass spectral and elemental analyses.
TABLE 1__________________________________________________________________________Spiroindanylsuccinimides ##STR3## Example # AmineSecondary ##STR4## mp °C. Yield Spectral Data.sup.1__________________________________________________________________________1 morpholine ##STR5## 103 58% 2.1-3.0(m,5H), 3.2 (s,2H), 7.1-7.5 (m,4H)2 piperidine ##STR6## 80-82 66% 1.1-1.8 (brs,6H), 2.0-3.5(m,10H), 4.5(s,2H), 7.1-7.5 (m,4H)3 N-(p-chloro- phenyl)- piperazine ##STR7## 185-187 91% 2.1-3.3(m,14H), 4.6(s,2H), 6.7-7.5 (m,8H)4 dibenzyla- N(CH.sub. 2C.sub.6 H.sub.5).sub.2 115-117 96% 2.3-3.3(m,6H), mine 3.8(s,4H), 4.6 (s,2H) 7.1-7.5 (m,14H)5 N-methyl- piperazine ##STR8## 113-114 67% 2.1-3.3(m,4H), 2.3 (s,3H) 2.4-2.80 (m,8H) 3.0(s,2H), 4.53(s,2H) 7.1-7.5 (m,4H)6 N-hydroxy- ethylpipera- zine ##STR9## 109-111 40% 2.2-3.4(m,17H), 3.4-3.9(t,2H),4.6 (s,2H),6.9-7.8 (m,4H)7 N-2" pyridyl)- piperazine ##STR10## 120-122 50% 2.0-3.3(m,10H); 3.4-3.9(m,4H); 4.6(s,2H); 6.5-6.9 (m,2H); 6.9-7.8 (m,5H); 8.1-8.4(m,1H)__________________________________________________________________________ .sup.1 HNMR Chemical shifts (ppm) in CDCl.sub.3 with TMS internal standard.
TABLE 2__________________________________________________________________________Spirocyclopentylsuccinimides ##STR11## Example # AmineSecondary ##STR12## mp °C. Yield Spectral Data.sup.1__________________________________________________________________________8 morpholine ##STR13## 69-71 55% 1.5-2.0 (m,8H), 2.5-1.8 (m,6H), 3.5-3.9 (q,4H), 4.5 (s,2H)9 N-methyl- piperazine ##STR14## 110-112 82% 1.3-3.6(m,8H), 2.5(s,2H)10 N-phenyl- piperazine ##STR15## 117-119 71% 1.3-2.3 (m,8H), 2.4-2.9 (m,6H), 2.9- 3.4 (m,4H), 4.3 (s,2H),6.6-7.5 (m,5H)__________________________________________________________________________
The anticonvulsant activity of these compounds was determined according to the standard pharmacological assay of Swinyard, et al, J. Pharmacol. Exp. Ther., 106, 319 (1952), using pentylenetetrazole and/or electroshock.
Briefly, a spirosuccinimide according to the present invention was administered to mice inraperitoneally as a suspension in 0.5% methyl cellulose in volumes of 0.09-0.3 ml. One half hour later, 85 mg/kg pentylenetetrazole was administered subutaneously. The results are scored in Table 3 wherein S means sedation, A means ataxia, and LRR means loss of righting reflex.
TABLE 3______________________________________Protection Against Penteylenetetrazole In Mice # of Ani- Obser- % Pro-Cpd mg/kg mals/dose vations tection______________________________________Spiroindanylsuccinimide 300 5 S -- 500 5 S 20Example #1 100 5 S -- 150 5 S 40 200 11 S,A 82 300 5 S,A,LRR 100Example #2 50 5 S -- 150 5 S -- 300 12 S -- 475 5 S,LRR -- 500 5 S,LRR 20Example #3 300 5 S --Example #4 400 5 S -- 800 5 S --Example #5 50 5 S -- 75 5 S 20 100 5 S 75 200 5 S 100Example #6 70 5 S 0 100 5 S 20 135 5 S 80 170 5 S 100Example #7 -- -- -- --Example #8 -- -- -- --Example #9 500 5 S --______________________________________
Anticonvulsant activity against electroshock was established as follows. One half hour after intraperitoneal administration of the test compound in 0.5% methyl cellulose in volumes of 0.09-0.03 ml, mice were subjected to a maximal electroshock of magnitude 50 ma/0.2 sec. Sedation, ataxia and loss of righting reflex were scored as before. The results appear in Table 4.
TABLE 4______________________________________Protection Against Maximal Electroshock In Mice # of Ani- Obser- % Pro-Cpd mg/kg mals/dose vations tection______________________________________Spiroindanylsuccinimide 50 5 S 0 100 5 S 40 150 5 S,A 100Example #1 100 5 -- 0 150 5 S 60 200 5 S,A 100Example #2 50 5 S 0 100 5 S 60 150 5 S,A 100Example #5 100 5 S 0 150 5 S,A 60 200 5 S,A 80 250 5 S,A 100Example #6 85 5 S 0 100 5 S 20 135 5 S 60 170 5 S 100______________________________________
Some degree of sedation was observed in all of the compounds tested, although this did not parallel protection against seizures. Although the spirocyclopentylsuccinimide Mannich base of Example 8 failed to provide protection against seizures in the pentylenetetrazole screen, several of the spiroindanylsuccinimide Mannich bases showed protective effects in both pentylenetetrazole and maximum electroshock assays.
The dose-effect curves for spiroindanyl derivatives (FIG. 1) in the two assay systems reveal the following:
In the maximum electroshock screen, the order of the activity was as follows:
Piperidine>Hydroxyethylpiperazine>Morpholine=N-Methylpiperazine>Parent Imide
ED.sub.50 Range (5 Cpds): 0.3 mM/Kg to 0.5 mM/Kg
The order of activity in the pentylenetetrazole screen was:
N-Methylpiperazine>Hydroxyethylpiperazine=Morpholine>>Piperidine>Parent Imide
ED.sub.50 Range (3 Cpds): 0.27 mM/Kg to 0.55 mM/Kg
It appears that the chemically-induced seizures are more sensitive to structural changes than seizures induced by electroshock. The piperidinyl and parent imides are most selective for MES-seizures, the N-Methylpiperazinyl imide is most selective for pentylenetetrazol seizures. The N-morpholino and N-Hydroxyethylpiperazinyl imides appear to be equiactive in both assays.
Various doses (0.3; 0.375; 0.5; 0.6 mM/Kg) of the hydroxyethylpiperazinyl Mannich base of indanyl-1-spirosuccinimide (Example #6) were injected (i.p.) into four groups of mice. Thereafter the mice were challenged by electroshock at various time intervals (15, 30, 60, and 120 minutes). The protective efficacy is presented in FIG. 2. Each data point represents n=5 mice/dose/time interval. The compound appears to rapidly penetrate the central nervous system as evidenced by the protection afforded 15 minutes after administration. Increased doses result in prolonged protection; a doubling of the dose leads to a tenfold increase in protective half-life.
The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification, as indicating the scope of the invention. | Mannich bases of spirosuccinimides are provided having anticonvulsant, sedative and antileukemic activity. The compounds have the following formula wherein ring A is a saturated or unsaturated monocyclic or bicyclic carbon ring of at least five carbon atoms: ##STR1## | 2 |
BACKGROUND OF THE INVENTION
(a) Field of the Invention
The present invention relates to a continuously operable fuel flow rate measuring device, and more particularly it relates to a continuously operable fuel flow rate measuring device of type comprising a variable orifice adapted to be controlled in connection with the total amount of air being drawn into an internal combustion engine, and a pressure regulator adapted to maintain the pressure difference across said variable orifice at a predetermined value.
(b) Description of the Prior Art
An arrangement has been known which comprises a single distributor, a plurality of variable orifices adapted to be simultaneously adjusted and optionally operable to determine the amount of fuel being supplied to a plurality of injectors, and a control valve for maintaining the pressure difference across each of said variable orifices at as constant a value as possible, the area of opening of each variable orifice being linearly variable with the axial displacement of the control spool.
In this connection, it is required that the area of opening of said orifice vary with the amount of air being drawn into the internal combustion engine. For advantageous positioning in the engine room and in order to attain an accurate control action, it is desired that the air flowmeter for measuring the suction air flow rate be connected directly to the above-mentioned control spool.
SUMMARY OF THE INVENTION
The present invention provides a construction comprising a sleeve having a substantially triangular measuring window communicating with the outlet port of a main body, said sleeve being inserted in the cavity of said main body, and a control spool having an annular groove communicating with the inlet port of said main body through an axially extending through hole and axially slidably inserted in said sleeve, said substantially triangular measuring window cooperating with said annular groove of said control sleeve to form a variable orifice. As a result of this construction, by axially sliding the control spool, any desired fuel rate can be easily obtained.
According to the invention, the end face of the control spool is resiliently pressed against a control rod adapted to transmit the displacement of a flow rate detecting valve disposed in a suction air passage to attain a direct correspondence between the degree of opening of the variable orifice and the axial position of the flow rate detecting valve. As a result, the amount of communication between the annular groove of the control spool and the triangular window of the sleeve will vary with the axial position of the flow rate detecting valve, i.e., with the amount of suction air, whereby the air-fuel ratio can be accurately maintained.
Because of the construction of the invention as described above, there is provided a fuel injection device which can be advantageously positioned in the engine room and which is high in the accuracy of flow rate measurement.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic view of a continuously operable fuel injection device according to the present invention;
FIG. 2 is a schematic view of the internal arrangement of a pressure control unit;
FIG. 3 is a schematic view of variable orifice;
FIG. 4 a schematic view of another embodiment of a pressure control unit; and
FIGS. 5 through 7 are sectional views showing different forms of the construction of a control spool.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
In the drawings, A designates a fuel injection device; B designates a suction air flow rate measuring mechanism for measuring the flow rate of air being drawn into an internal conbustion engine; and C designates a fuel measuring and distributing mechanism for measuring and distributing fuel.
In the suction air flow rate measuring mechanism B, the numeral 1 designates a servo-mechanism utilizing a fluid, comprising a servo-valve 2 and an actuator 3 disposed in an air cleaner; and 4 designates a measuring mechanism for maintaining the pressure difference (P 1 -P 2 ) across a flow rate detecting valve 6 disposed in a suction passage 5 at a constant value by means of said servo-mechanism and measuring the suction air flow rate from the area of opening of the flow rate detecting valve 6. In the fuel meauring and distributing mechanism C, the numeral 7 designates a main body comprising an upper member 8, an intermediate member 9 and a lower member 10; 11 designates a sleeve disposed in a hole 12 formed in the main body at the center thereof; 13 designates a control spool disposed in the sleeve 11 so that it is axially displaceable by a control rod 14 which transmits the displacement of said flow rate detecting valve 6; 15 designates a spring which presses the control spool 13; 16 designates an annular groove formed in the outer periphery of the control spool 13; 17 designates substantally triangular windows formed in the sleeve 11; and 18 designates a pressure control unit. The pressure control unit comprises a diaphragm 19 clamped between the intermediate member 9 and the lower member 10, a valve seat 20 fixed to said diaphragm 19, a ball 21 seated in said valve seat 20, a springy reed 22 clamped between the upper member 8 and the intermediate member 9, a valve barrel 23 inserted in the upper member 8, and a spring 24 pulling the diaphragm 19 downwardly as seen in FIG. 1.
The construction of the control spool 13 is as shown in FIG. 5. Thus, the control spool 13 comprises two independently produced spools 131 and 132 which are urged against each other by a spring 133 to define an annular slit 134 between the spools 131 and 132. One spool 131 comprises a central projection 135, a lowered peripheral edge 136, a peripheral groove 137, one or a plurality of axial through holes for feeding fuel to the peripheral groove 137, and a spring seat 139 formed on the other end. The other spool 132 has one or a plurality of axial through holes 140. The spring 133 serves to urge said spools 131 and 132 against the control rod 14 in such a condition that the spools are put together end to end. Because of the construction described above, the annular slit 134 formed around the entire periphery encircling the butted surfaces of the spools 131 and 132 is determined by the level difference between the central projection 135 and the peripheral edge 136. In addition, the central projection, the lowered peripheral edge and the peripheral groove in the spool 131 may be provided in the other spool 132 instead of in the spool 131. As for the axial through holes 138 and 140 provided in the spools, it is sufficient to provide them in only one of the spools if communication passages are provided in the outer periphery of the spool.
FIG. 6 shows another embodiment of the control spool 13. According to this embodiment, separate spools 131 and 132 are axially centrally formed with a through hole 141 and the two spools are axially adjustably connected together by a shaft 142 loosely inserted in one or both of the spools, springs 143 and stop rings 144 and 145. When the spools are assembled into the sleeve having the triangular windows, the alignment between the two spools is effected by the inner surface of the sleeve.
FIG. 7 shows a further modification of the control spool 13, wherein none of the separate spools 131 and 132 are formed with a central projection. The spools are provided with through holes 146 and 147 and are axially adjustably connected together by a shaft 148 loosely inserted in one or both of the spools 131 and 132, a shim 149 which provides a desired slit width, springs 150 and stop rings 151 and 152. When the spools are assembled into the sleeve having the triangular windows, the alignment between the two spools is effected by the inner surface of the sleeve.
With the control spool constructions described above, the production of the separate spools does not require any special machining process for cutting the annular slit, because it is only necessary to provide a difference in level between the central projection and the peripheral edge in order to define such annular slit. Therefore, the machining operation is easy and high machining precision can be easily attained. Further, in the control spool of FIG. 7 which does not require the central projection, it is only necessary to prepare a shim of required thickness.
This device operates as follows.
When a throttle valve 23 is manipulated, the pressure difference (P 1 -P 2 ) across the flow rate detecting valve 6 will deviate. This pressure change will be detected as a displacement of the pressure difference setting diaphragm 26 of the servo-valve 2, said displacement bringing about a corresponding change in the area of opening 28 of the variable orifice 27. Eventually, the pressure P n (P' 2 <P n <P 1 ) in the bellows 29 of the actuator 3 will change, causing the flow rate detecting valve 6 to be further opened or closed until the pressure difference (P 1 -P 2 ) resumes its predetermined value. In addition, the numeral 30 designates a venturi serving to provide a negative pressure source for the servo-mechanism 1.
The above refers to a case where it is desired to make the amount of suction air proprtional to the volume rate of flow. However, when it is desired to make it proportional to the weight rate of flow, a density compensation bellows 31 will be provided so that it can be interlocked to said pressure difference setting diaphragm 26. The effective area of the bellows 31 is selected so that it is equal to the expression (the effective area of the pressure difference setting diaphragm 26)×(the pressure difference at the reference temperature and pressure)÷(the pressure of a reference gas enclosed in the bellows 31). The bellows 31 is installed in parallel to the pressure difference setting spring 32 and takes a share in setting the pressure difference.
When the flow rate detecting valve 6 is opened and closed in proportion to the amount of suction air, the control spool 13 interlocked to the flow rate detecting valve 6 is also displaced within the sleeve 11. Therefore, the amount of communication between the annular groove 16 of the control spool 13 and the triangular windows 17 of the sleeve 11 changes with the amount of suction air and hence the intended air-fuel ratio is maintained accurately.
The fuel is pumped from a fuel tank 33 into the main body 34 by a fuel pump 34 while it is maintained at a predetermined pressure by a pressure regulator 35, part of the fuel being led through a hole 36 and into the lower chamber 37 of the pressure control unit 18, from which it is fed back to the tank 33. The rest is led through the metering gate 16, 17 and into the upper chamber 38 of the pressure control unit 18, from which it is passed through the reed valve 21, 22, 23 to the associated fuel injector (not shown) attached to the air suction pipe. The reed valve 21, 22, 23 so acts that the fuel pressure Pb in the upper chamber 38 will have a fixed value set by the pressure Pa in the lower chamber 37 plus the pressure exerted by the tension spring 24. Consequently, the pressure drop (Pa-Pb) across the fuel metering gate 16, 17 is maintained at a fixed value, so that the amount of communication of the fuel metering gate 16, 17 is proportional to the rate of flow of fuel. In addition, the fuel is also acting on the upper surface of the spool 13 through the through hole 39 of the spool 13.
In the drawings, a single pressure control unit 18 has been shown installed to the fuel measuring and distributing mechanism. It is to be noted, however, that the same number of such pressure control units as the number of cylinders of the engine are disposed around the fuel measuring and distributing mechanism. The annular groove 16 and triangular windows 17 may be replaced by the slit type provided that the area of opening of the orifice is proportional to the amount of suction air.
FIG. 4 shows another embodiment of a pressure regulator. This pressure regulator 40 has two chambers A and B separated from each other by a diaphragm 41. The chamber A is provided with a communication hole 42 communicating with the outlet port of the flow rate measuring device, and a communication hole 44 communicating with an injector 43, the discharge pressure being Pb. The chamber B is provided with a communication hole 45 communicating with the lower chamber underneath the control spool of the flow rate measuring device, a supply pressure Pa being exerted therein. A reinforcing plate 46 is attached to the diaphragm 41. In the chamber A on one side of the reinforcing plate 46, a valve ball 48 made integral with a large articular ball 47 as by welding is rotatably installed as held by a presser member 49 and is subjected to the influence of an energy storing spring 50. The numeral 51 designates a valve seat disposed in the communication hole 44 and having a conical surface 52, said valve seat cooperating with the valve ball 48 to form a passage 53 for fuel. In the chamber B on the other side of the reinforcing plate 46, a pressure difference setting spring (which is a tension spring) 54 is installed through the intermediary of an adjusting screw 55, the force of said spring serving to set the pressure difference (Pa-Pb) between the chambers A and B. The function of said pressure regulator is the same as that of the pressure regulator shown in FIG. 1 and hence a description thereof is omitted.
The present invention is not limited to the embodiments described above and may of course be modified into various forms without departing from the true scope and spirit of the invention. | A continuously operable fuel injection device comprises a sleeve having a substantially triangular measuring window communicating with the outlet port of a main body, the sleeve being inserted in the cavity of the main body, and a control spool having an annular groove communicating with the inlet port of the main body through an axially extending hole and axially slidably inserted in the sleeve, the substantially triangular measuring window cooperating with the annular groove of the control sleeve to form a variable orifice. By axially sliding the control spool, any desired flow rate can be obtained. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to the packaging field, and more particularly to a laminated thermoplastic film which can be used to produce a heat-sealable, heat-shrinkable bag having a polyester external surface.
The use of heat-shrinkable thermoplastic films is well known to the packaging industry. For example, poultry products are typically sealed within bags made from such films and heated, thus shrinking the bag until it fits tightly about the product.
One type of thermoplastic material currently used to form such bags is monolayer polyester film. Polyester bags have many advantages. For instance, they provide strength and protection through tight adhesion to the product. Also, printing onto treated polyester tends to be somewhat more stable than onto other thermoplastic materials. However, a problem exists in that polyester is not heat-sealable except at exceptionally high temperatures, and as a result such bags must be sealed with adhesive. Bags sealed with adhesive are not as strong in the seal area as than heat sealed bags, cannot be closed on the open end by existing heat seal equipment and cannot be printed so as to lock or protect the printing.
A second type of heat-shrinkable bag currently in use is made of co-extruded, heat-shrinkable, thermoplastic films, such as polyolefin. For example, U.S. Pat. No. 3,299,194 to Golike and U.S. Pat. No. 3,663,662 to Golike et al. disclose shrink films of oriented polyethylene and various copolymers of ethylene. U.S. Pat. No. 4,597,920 to Golike teaches a shrink films which is a copolymer of ethylene with at least one C 8 -C 18 α-olefin. Methods for producing multi-layer thermoplastic film are provided in U.S. Pat. No. 2,855,517 to Rainer et al., U.S. Pat. No. 3,022,543 to Baird, U.S. Pat. No. 3,754,063 to Schirmer, and U.S. Pat. No. 3,981,008 to D'Entremont.
Coextruded films, such as polyolefins, are useful in producing heat-shrinkable bags because they are heat-sealable and therefore can be produced on existing heat seal equipment economically. They maintain good physical contact with a packaged product after heat shrinking, and thereby retain juices within packaged meats, but not as well as the laminated shrink bags. However, coextruded films have different mechanical properties, such as tensile strength and modulus, and therefore bags made from these films are more apt to tear or otherwise become physically damaged during handling than a multilayer lamination. Another important disadvantage is that you cannot reverse print or lock the print between the film layers, whether by surface or reverse print, with coextruded films, making them exposed to abuse, abrasion, and removal of the print by physical or chemical action.
Therefore, there exists a need for a thermoplastic film which combines the advantages and eliminates the disadvantages associated with monolayer polyester and coextruded films.
More particularly, there exists a need for a film which is strong, which is heat-sealable, and which eliminates the problem associated with surface printing.
SUMMARY OF THE INVENTION
The present invention relates to a heat-sealable, heat-shrinkable laminate film, as well as a bag or other packaging produced from the film.
The film is comprised of first layer of heat-shrinkable thermoplastic material laminated to a second layer of heat-sealable, heat-shrinkable thermoplastic material which has similar shrink characteristics to the first layer and an adhesive which adheres the two layers together. In this way, the first and second layers will shrink at approximately equal rates, thereby providing a uniform appearance and structural stability both during the lamination process and in a package produced with the film.
In one embodiment, the first layer may be a polyester, such as polyethylene terephthalate, and the second layer may be a polyolefin, such as polypropylene or polyethylene. The two layers may be adhered together on a standard laminating machine using processes that allows the lamination to occur without undue shrinking.
The film may be used to produce a heat-shrinkable package, such as a bag. For example, a length of the film may be folded to form two sections so that the second layers of each section contact one another to form the inner surface of the bag and the first layers form the outer surface of the bag. The edges of the sections may be heat-sealed to adhere the second layers together and produce the final bag structure.
Therefore, it should be clear that the present invention provides a thermoplastic film which combines the advantages and eliminates the disadvantages associated with monolayer polyester and co-extruded films. For instance, the film of the present invention may be used to produce a bag having a strong, printable polyester outer surface and a clean, heat sealable inner surface. Furthermore, indicia may be reverse printed on the inner surface of the first layer, or, the surface of the second layer, and thereby protected in the final product.
These and other advantages are explained in more detail in the following detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a schematic diagram representing a cross-sectional view of the film of the present invention;
FIG. 2 is a perspective view of a heat-shrinkable bag made in accordance with the present invention; and
FIG. 3 is a cross-sectional view of a side of a bag made in accordance with the present invention.
DETAILED DESCRIPTION OF THE INVENTION
The heat-sealable, heat-shrinkable thermoplastic laminate film of the present invention has the cross-sectional appearance shown in FIG. 1. The film 10 comprises a substrate 12, or first layer, adhered to a second layer 14, by means of a layer of adhesive 16.
The substrate 12 is comprised of a sheet of polyester, such as HS heat-shrinkable polyethylene terephthalate (see, R. W. Moncrieff, Man-Made Fibres, John Wiley and Sons, New York, 4th ed., 1963). Polyethylene terephthalate typically has gauges from 50 to 150 and is designed to shrink approximately 50% at a temperature of 100° C. The specific type of polyethylene terephthalate employed depends upon the specific end use of the film 10. For example, if the end use is one that does not require a high barrier against moisture transmissions or oxygen permeability, the substrate 12 may be polyethylene terephthalate types HSV-65 or HSV-150, available from E. I. Du Pont de Nemours Company, Wilmington, Del. If an extremely high barrier against moisture vapor transmission, as well as against oxygen permeability, is desired, types XM-927-65 or XM 927-150, available from E. I. Du Pont de Nemours Company, Wilmington, Del., may be employed. These "XM" types are polyethylene terephthalate film coated with a polyvinyldine chloride coating, and are particularly useful for extending the shelf lives of meat or poultry products. A third type of film, such as HS-65 and HS-150, available from E. I. Du Pont de Nemours Company, Wilmington, Del., has a relatively high melting point and therefore is desirable for use in high temperature applications such as cooking meat products.
The second layer 14 may be of any thermoplastic material which is heat-sealable and which has approximately the same shrinking characteristics, attained by a blow-up ratio or orientation, as the substrate 12. For example, the second layer 14 may be comprised of a polyolefin, such as polypropylene or polyethylene. Also, a 1.00 mil to 3.00 mil ionomer extrusion produced by Tara Plastics of College Park, Georgia from one of #1601, #1650 and #1652 Surlyn® resin (ethylene-methacrylic acid di-and ter-polymers) supplied by E. I. DuPont de Nemours and Company may be used. The ionomer is particularly useful in that it has been found to adhere to packaged meat during cooking and prevent loss of juices therefrom during this process. The second layer 14 may be produced by standard extruding to a blow-ratio or orientation conducive to shrink, and should achieve an approximately 50% shrink at 100° C.
The term "shrink characteristics" means the ability of film to be oriented in such a way as to cause it to shrink in size, both longitudinally and latitudinally when subjected to certain temperature levels. This orientation causes a change in the molecular structure of the film, that when subjected to the higher temperature causes this molecule configuration to attempt to return to its original structure. This can be done in a number of ways, but all include the changing of time, temperature and pressure on the film.
The adhesive layer 16 may be comprised of any type of adhesive which will effectively secure the substrate 12 to the second layer 14 for the intended purposes of the film 10. For example, the adhesive must maintain the attachment at high temperatures so that the film 10 can survive heat shrinking, as well as cooking if so desired, without damage. One adhesive which may be used is a polyurethane type lamal HSA adhesive and a CR180 catalyst, available from Morton Thiokol Inc., Morton Chemical Division, Chicago, Ill. Another type of adhesive may be a water based adhesive, such as Morton #2018.
Printed matter 18 may be placed onto the substrate 12 in any known manner. The printing may be provided on the outer surface 20 of the substrate 12, in which case the printing process may be performed either before or after the adhering of the substrate 12 and second layer 14. It is also possible to provide the printed matter 18 on the inner surface 22 of the substrate 12 so that the printing becomes protected between the substrate 12 and second layer 14 in the film 10. Printed matter 18 may also be placed on the inside surface of sealing layer 16 in which case the printed matter would also become protected between the substrate 12 and the second layer 14 in the film 10.
The film 10 may be produced on a standard laminating machine, such as available from Dri Tech, New Berlin, Wis. The similarity in shrink characteristics of the substrate 12 and second layer 14 eliminates problems caused by the heat shrink associated with production. A roll of substrate 12 and a roll of the second layer 14 are held separately on the laminating machine. The rolls are unwound into the lamination process while the machine speed is set at approximately 300 to 400 feet per minute, the oven temperature at approximately 22° C.-82° C. (72° F.-180° F.), the web temperature at the same temperature as the oven, and the adhesive applied at a weight of 1.25±0.25 lbs. per ream. The laminator nip temperature should be approximately 65° C. (150° F.) and the nip pressure should be approximately 30-50 P.S.I. using a first treater set at 20 to 40% and a second treater set at 50 to 90%. The chill rolls should set the film 10 running at 15° to 27° C. (60° F.-80° F.).
The film 10 may be made into shrinkable bags 24, such as shown in FIG. 2. The bag 24 may be produced by folding a sheet of film 10 into two equal length sections 26,28 so that the substrate 12 comprises the outside portion 30 of the bag 24 and the second layer 14 comprises the inside portion 32. To complete the bag 24, the side edges 34 of the film 10 are heat sealed together, preferably at a low temperature, such as by impulse sealing. As shown in cross-sectional view in FIG. 3, upon application of heat, the second layer 14 of the first section will seal to the second layer 14 of the second section. | A heat-sealable, heat-shrinkable laminate film having a first layer of heat-shrinkable thermoplastic material and a second layer of heat-sealable, heat-shrinkable thermoplastic material adhered to the first layer, the materials of the first and second layers having similar shrink characteristics. | 1 |
BACKGROUND OF THE INVENTION
Related Applications
This application is a continuation-in-part of application Ser. No. 103,322, filed Dec. 14, 1979, application Ser. No. 145,657, filed May 2, 1980, and application Ser. No. 210,923, filed Nov. 28, 1980 all abandoned.
Iron may occur in water as an already-precipitated iron floc, in soluble form or in a colloidal state. Two or all three of the above types may coexist. For the purposes of this invention, the soluble as well as the insoluble forms of the iron are converted to colloidal dimensions.
Where iron occurs as an insoluble floc, such water is commonly known as "red water." "Red water" is objectionable from an aesthetic point of view, and also deposits out to stain. When iron occurs as "red water" partial or even complete oxidation of the iron has already taken place. The insoluble ferric compounds responsible for the rust color can be removed by a filter, but any remaining soluble ferrous compounds will be subsequently oxidized to deposit downstream.
Iron is present in soluble form in a large proportion of waters, and is one of the most troublesome components of domestic and industrial water supplies because it is extremely difficult to remove, particularly from well water. Iron commonly occurs in well water as the soluble ferrous bicarbonate. Well water is normally not exposed to air until it has been drawn from the well, and so is clear as drawn, but upon exposure to the air it slowly forms an adherent deposit of the insoluble hydrated ferric compounds. The compounds are dark-colored and, consequently, if they are deposited on bathroom or kitchen fixtures, clothes, and other surfaces, ugly stains result which are difficult to remove.
It has been known for some time that the soluble ferrous iron present in water can be oxidized to insoluble hydrated ferric compounds upon contact with catalytic manganese oxides. The manganese higher oxides may be provided in a filter as an impregnant on a particulate carrier or as a ground manganese-containing ore. However, the oxidation of the ferrous iron by the manganese oxide results in reduction of the manganese oxide, which then has to be regenerated by treatment with a permanganate salt. This greatly increases the cost of the process and renders it impractical for ordinary household use. Correct dosage is difficult, which means that if there is excess permanganate present that can pass downstream of the filter, it can create as many problems as the iron which the filter is supposed to remove.
The usual way for removing iron from domestic water supplies, such as for household use, is by passing the water through a bed of cation exchange resins. The resin has to be regenerated periodically by treatment with aqueous sodium chloride to restore its ion-removing capacity.
Cation exchange resins used for water softening are not very efficient in the removal of iron. Iron collected in the bed is difficult to desorb during the brine regeneration step. Iron is not readily removed by sodium chloride treatment and requires the inclusion in the brine of an agent such as sodium hydrosulfite or a citrate. Moreover, iron in the water deposits on and plugs the conditioner controls, leading to frequent shutdowns and service calls. If "red water" is passed through the bed, fouling of the resin bed occurs, considerably shortening the onstream cycle.
Soluble ferrous iron can also be oxidized to form filterable hydrated ferric compounds by treatment with agents such as chlorine, hypochlorite, and chlorine dioxide.
In large water supply systems such as municipal or industrial plants, iron is removed in a soda-lime water softening process or in the aeration of water, followed by filtration.
Aeration of the water is carried out by a variety of means described widely in the literature. Aeration equipment has as a design feature maximum surface exposure of the water to air to promote dissolution of the air in the water. For instance, the cascading of water over slats, the sprinkling of water through air, and the introduction of air into water by the use of spargers is widely practiced. All these methods do speed up the dissolving of the air in the water, but the process is relatively slow due to the surface tension barrier of the water. Equipment is large and its efficiency is poor, unless means is provided to raise the pH of the water.
Reading from Water Supply, Treatment and Distribution by Walker, page 202:
Simple aeration may be all that is required to precipitate the ferrous bicarbonate as ferric hydroxide in accordance with the following equations: ##STR1## further aeration: ##STR2## In order that the reaction will go to completion and precipitate the ferric hydroxide, it is necessary that the pH be approximately 7 or higher. If possible, the pH should be raised to 7.5 to 8.0, but even so the reaction may take 15 minutes retention before it is complete, and in some cases as much as 1 hour retention has been necessary.
It is postulated by the applicant that the surface tension lowering of the water at higher pH accelerates air dissolution in the water to complete the oxidation of the ferrous iron. Such a process is described by McLean in U.S. Pat. No. 3,649,532, wherein his aeration device purposely gives delayed and incomplete oxidation until the water enters an alkalizing mineral bed.
A concern of the prior art practitioners was the tendency for a portion of the soluble ferrous iron to precipitate out of the water as a colloid. Because of the small dimensions of the colloidal particles, it was thought they could not be trapped in a conventional filter. Expensive precoagulation steps were thought necessary, and are routinely used before filtration to precipitate the iron hydrates.
Reading from the Journal of the American Water Works Association, Volume 50, page 689 (1958):
Aeration readily oxidizes ferrous bicarbonate from the soluble form to ferric hydrate, and the hydrate, though present even in the colloidal size, is readily adsorbed and absorbed by conventional flocs produced by the reaction of alum or any of the ferric coagulant.
Reading from the Nalco Water Handbook, Nalco Chemical Co., pp. 10-15 (1979):
A fourth aspect of the precipitation process is the zeta potential of the initial heavy metal colloidal precipitate. In many plants where heavy metals are being removed, one of the principal problems in reaching the desired effluent limits is the colloidal state of the precipitated materials--they have not been properly neutralized, coagulated and flocculated.
The process of the present invention uses colloid formation to advantage. It purposely colloidalizes substantially all of the already-precipitated iron hydrate in the water while simultaneously introducing air therein to oxidize the soluble iron. High shear and zones of decompression/compression to which the water is subjected overcome surface tension phenomena and rapidly dissolve air in the water to accelerate its reactivity with the soluble iron to convert it to ferric hydrates, colloidally precipitated. Such colloidal particles inherently carry a surface charge; the very high dispersion factor of the so-formed colloidal system results in enhanced particle surface charge, which makes possible iron removal in a bed of particulate material containing at least localized sites of the opposite charge.
The process of Lawlor et al. U.S. Pat. No. 2,237,882 typifies an aeration procedure of the prior art to remove iron from water. Lawlor et al. use a crock diffuser, air being supplied by an air compressor. The air passes through the pores of the diffuser into a stream of the iron-containing water in the form of "minute bubbles." Although some iron hydrate colloid may result from such treatment, this method of introducing the air is not conducive to the formation of a colloidal dispersion. The "minute bubbles" themselves carry a negative charge and serve to attract and coagulate any iron hydrate micelles on their surface.
Particulate materials suitable for use in the applicant's filter are numerous. The activity of these materials to precipitate electrostatically-charged micelles depends on the creation on their surface or in their environment of an opposing charge. They are primarily selected on the basis of properties such as rough or porous surface, which increases surface area in the filter bed, and ion exchange capacity to take up such polyvalent ions as calcium and iron to provide localized sites of positive charge in an otherwise negatively-charged media. Particulate materials of choice thus carry both negatively and positively-charged sites to precipitate, respectively, positively and negatively-charged micelles. After the particulate media have exchanged the polyvalent ions, they remain electrostatically active but chemically inert. Applicant has no need to treat the media with an oxidizing chemical such as permanganate, or to use alkalizing materials in the filter to raise the pH to catalyze iron oxidation.
So far as is known, any material capable of carrying a charge in contact with water and capable of being subdivided or compressed into a particulate form and provide a reasonably rough or porous surface, can serve as a filter bed. No continuing chemical interaction is involved so far as is presently known, and no catalytic effect has been detected. The aeration of the water under pressure and high shear is evidently sufficiently quantitative to convert the iron hydrates to colloidal dimensions. Phase boundary interaction between the variously charged micelles and the particulate material through which the water flows leads to a rapid and substantially complete precipitation and removal of the colloidal components.
Because of the small size of the iron-containing micelles, they can penetrate through the upper layers of the filter bed and provide a depth filtration. Iron removal by the prior art, which involved flocculation and sedimentation, resulted in deposition of floc in the upper layers of the filter, causing plugging and necessitating frequent backwashing.
SUMMARY OF THE INVENTION
The process of the present invention is adapted for continuous operation and is capable of removing iron in a single-pass, flow-through system, comprising the steps of:
(1) colloidalization of the iron in water under conditions of high shear and decompression/compression to finely divide existing insoluble iron hydrates, and by dissolving therein air in sufficient amount to oxidize and form colloidally dispersed iron hydrates from the dissolved iron present, thereby providing substantially all the iron in the form of micelles having a surface charge;
(2) maintaining the waater under a pressure within the range of about 10 to 500 psig;
(3) then passing the water under a pressure within said range through a mass of particulate material having a surface charge of attracting, removing, and collecting the dispersed iron hydrates; and
(4) recovering water containing less iron than the starting water, and preferably less than 0.3 mg/liter of iron.
The iron hydrates collected throughout the mass of particulate material are non-adherent and can be easily removed by backwashing.
The term "iron hydrate" as used herein includes any insoluble compound of ferric iron containing water of hydration such as the iron oxides and the hydroxides. Such compounds usually contain ferric iron as cation, but may consist of ferro-ferric complexes. Ferric hydroxide, hydrous ferric oxides, hydrous ferric carbonates and silicates are representative of such compounds.
The bed of particulate material should be held under pressure. It can be placed in a pressure vessel provided with controls for periodic backwash. Such procedure assists in holding the air in solution and completing its reaction with the ferrous iron. Pressure also reduces any tendency for the air to gas-out in the filter media to produce a barrier on the surface of the granules. The bed of particulate material should provide sufficient dwell time to destabilize the iron-containing micelles and precipitate them in the media.
The necessary aeration of the water under the conditions of high shear can be accomplished by a variety of devices. Such device acts as a jet compressor, air being added in controlled amount into a zone of violent agitation. Distinguished from the prior art aerations, the air so added is rapidly solubilized in the water to serve without any additional agent to oxidize the soluble iron and form the colloidal iron hydrate micelles.
Preferred devices that can be used are made up of three basic components: a nozzle, a diffuser, and a housing holding these parts in their relative positions to provide a mixing chamber for the air and the water. Usually, a suction tube terminates in such chamber for the introduction of the air. A device of this type comprises in combination:
(1) a housing having an inlet for water, an inlet for air, and an outlet for aerated water;
(2) a chamber in the housing for adding air to the water, mixing and dissolving it therein;
(3) first, second, and third flow passages in the housing interconnecting the water inlet, the air inlet, and the aerated water outlet, respectively, with the chamber;
(4) means in the first fluid flow passage for projecting a high velocity jet stream of water or air into the chamber across the inlet into the chamber of the second fluid flow passage in a manner to draw air or water from that passage into the chamber and into the high velocity jet stream and obtain violently turbulent mixing of the two components;
(5) means for controlling the volume amount of at least one of the flows of water or air into the chamber to control the amount of air dissolved in the water;
(6) diffuser means receiving the flow of the aerated water from the chamber and delivering it to the outlet of the housing; and
(7) water retention means for maintaining the fluids throughout their passage through the housing under a pressure within the range of 10 to about 500 psig.
BRIEF DESCRIPTION OF THE DRAWINGS
Preferred embodiments of the invention are shown in the drawings, in which:
FIG. 1 is a flow sheet showing the apparatus components of a domestic or household water system including the apparatus of the invention;
FIG. 2 is a longitudinal section of the injector-mixer of FIG. 1;
FIG. 3 is a flow sheet showing the apparatus components of a municipal or community water system including the apparatus of the invention;
FIG. 4 is a longitudinal section of the injector-mixer of FIG. 3; and
FIG. 5 is a graph showing zeta potential, as determined on the Riddick Zetameter, against pH for hydrous ferric oxide floc, hydrous ferric silicate floc, and hydrous ferric oxide floc prepared in the presence of calcium ion.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A typical device according to one aspect of this invention is shown in FIG. 2, which illustrates the requirements for the process. Such device is called an injector-mixer. It consists of a water inlet 20 and a water outlet 21, interconnected by a flow passage 24 which contains a nozzle 28 terminating in a chamber 30. The chamber 30 has a suction inlet 31 and an outlet 32 which leads into a diffuser 29. The position of the chamber 30 is critical in relation to the nozzle 28, the diffuser 29, and the suction inlet 31 to create a proper suction and provide a zone for air-water mixing.
The suction inlet 31 provides for air intake into the chamber 30. The air thus introduced rises violently with the water ejected from the nozzle into the chamber. Control of the amount of air added is accomplished by the setting of a screw 35, which is housed adjacent to an inlet 36. An air flow passage 37 interconnecting the inlet 36 with the suction inlet 31 has a section 38 housing a ball check valve and defining an annular passage for air flow past a ball 39. When fluid flow through the nozzle ceases, as by shutdown of a pump, so does aspiration of the air. Fluid pressure in the system closes the ball check valve, the ball 39 seating against the sealing gasket 34.
The device may also contain a bypass to divert from the nozzle a portion of the water being pumped. Such bypass may be enclosed in the same housing as the flow passage 24 (see FIG. 2) or it may be external to the body of the injector-mixer. In FIG. 2, the flow passage is divided into two sub-passages 23 and 24 by the wall 25. The amount of water passing through the bypass is controlled by positioning the screw 26, which can be moved between positions all the way across the passage to the wall 25, or fully withdrawn into the threaded socket 27. If the bypass is external to the housing, an auxiliary valve in this line controls the amount of water diverted from the nozzle.
The bypass is a desirable feature, since the amount of air intake through the suction tube is proportional to the amount of water passing through the nozzle. The valving in the bypass to divert more or less water from the nozzle provides a complementary means of air dosage control. The bypass also increases the amount of water which can be pumped through a given size injector-mixer without placing excessive back-pressure on the pump. In the suction chamber, the air and water are violently mixed, and the mixture escapes via the diffuser 29 to be turbulently blended into the bypass stream. The conditions of high shear and decompression/compression of the water lead to very rapid dissolution of the air in the water to react with the dissolved iron and form the colloidal system desired. The air is first drawn through the suction tube into the chamber, an area of decompression; then it is compressed again as it moves, mixed with the water, down the diffuser.
Another type of injector-mixer that is particularly adapted for use in larger systems such as municipal supplies, where greater volumes of water are pumped and more air is involved, may take several forms. The device may consist of a succession of nozzles, followed by expansion chambers enclosed in a single housing and terminating in a single diffuser. Controlled amounts of air are introduced into at least one chamber by a suction tube equipped with a check valve and valve for controlling air intake. The additional shear and decompression/compression through the subsequent nozzle or nozzles for the air-water mixing lead to complete dissolution of the air in the water, and quantitative oxidation of the soluble iron to form the colloidal dispersion.
Other municipal systems where the piping is large may find it more advantageous to use air as the motive force. An injector-mixer is immersed in a pressurized stream of pumped water and air from a compressor is injected through the nozzle to suck in water via orifices peripheral to the chamber. Such a device is shown in FIG. 3.
Still another method of injecting controlled amounts of air into the water is by insertion of a snifter valve containing check means into a water system upstream of the mixer, such as on the suction side of a pump. The snifter valve will open to draw in air when the pump is running, but will close on pump shutoff. The amount of air added through the snifter valve must be carefully controlled by screw or other means to provide enough oxygen for iron oxidation but not enough to cause the pump to lose its prime. The air-water mixer inserted downstream of the snifter valve has no need to draw in air, but can take the form of a nozzle or series of nozzles with diffuser.
While the aeration of the water clearly results in at least partial oxidation of the ferrous iron to a ferric state, and most such ferric compounds show a rusty hue in water, the aerated water downstream of the injector-mixer may nevertheless be clear to the naked eye. The iron hydrates contained therein probably exist in the form of an invisible sol. Retention of the iron hydrates in a colloidal state and avoidance of their coagulation are important features of the invention, so that a large surface area of highly charged micelles may be presented to the particulate media during the filtration step.
It has been noted that particulate materials having a rough surface, such as a nodulous or porous surface, and therefore an appreciably larger surface area, tend to attract, collect, and remove the iron hydrate micelles more effectively. Porous, rough-surfaced materials such as pumice and diatomite are especially good examples of suitable materials. The materials can be rough, as naturally occurring after being subdivided to a convenient particle size, or as synthetically compacted or compressed into shapes or aggregates from smaller particles, such as extruded rods.
Exemplary particulate materials are the siliceous rocks, such as silica sand and diatomaceous earths, the aluminum silicates including the milled-classified materials and extruded or compressed materials, e.g., the bentonites, kaolin, feldspar, the zeolites, perlite, pumice, and other forms of lava. Perlite and pumice are especially effective, and are preferred. Also satisfactory are the magnesium silicates, such as talc. Natural aluminas, such as bauxite and the purified bauxites (Al 2 O 3 ), and the hydrated aluminas can be used, as well as the dolomites, limestone, and magnesia, and the various mixed forms such as partially calcined dolomite, calcium carbonate, magnesium hydroxycarbonate, and magnesium aluminum oxide (MgO.Al 2 O 3 ). The various forms of carbon such as coke, charcoal and activated carbon extrusions or compressed shapes are also suitable. Mixtures of two or more of these materials can be used. As is evident, the range of suitable filtering materials is large. The common requirement for such suitable materials is that they offer a charge surface in contact with the water.
The particle size of the particulate material is such as would prevail in any filter. Finer materials tend to cake and block the flow, while the larger particles do not provide a sufficiently large surface area so that beds of impractical size have to be employed.
The colloidal system which results from the aeration of the water passing through the injector-mixer is complex, and in fact may vary from water to water. It is known that pH plays an important role in determining the type of charge on the micelles. As shown in FIG. 5, hydrated ferric oxides in distilled water carry a positive charge below pH 6.5, above which point they carry an increasingly negative charge as the pH rises. The curves also show the effect of ionic calcium on the zeta potential of the hydrous ferric oxide dispersion, making it more positive in nature.
Potable waters usually have a pH within the range of 5.5 to 9.5. The process of the invention successfully removes iron within this range, most proficiently within the range of about 6.5 to 7.5. When the water contains free acid, as is common in some parts of the country, dolomite, limestone, and their partially calcined counterparts or magnesia aggregates may be used in the filter. They serve to take up such acid and raise the pH to 5.5 or more, acting also to precipitate and collect the iron-containing micelles in the filter.
Most well waters contain silica, and in this instance a colloidal hydrous ferric silicate is probably formed. By referring to FIG. 5, it is seen that the floc consisting of hydrous ferric silicate shows the expected negative charge, even at a pH as low as 5.5. Moreover, hydrous ferric oxides and hydroxides readily adsorb multivalent cations of the type of Ca++ and Fe+++ to increase their positive potential and act in the filter bed to remove negatively-charged micelles.
FIG. 1 is a flow sheet showing the components of a domestic water system, including an apparatus embodying the innvention. Such domestic water system receives water pumped from a well W via line 1, which is led into the injector-mixer 2 shown in detail in FIG. 2. The aerated water passes into line 4, which directly downstream of the mixer is tapped via line 5 and valve 6 for sampling the aerated water. Such sampling permits monitoring of the amount of oxygen in the water at this point. Most pressurized water systems include a water holding tank such as tank 7 equipped with a pressure switch. Either an air-blanketed tank or a diaphragm-containing tank may be used. However, even when water is pumped directly to the bed of particulate material held in tank 12, iron residuals are often reduced to acceptable levels in the effluent water, since the oxidation of the soluble iron compounds in the water proceeds rapidly in the injector-mixer. When used, water enters the pressure holding tank 7 via the line 8 at the bottom until the tank is under a predetermined maximum gauge pressure, say 40 psig, and then the pressure switch kicks off, shutting off the pump. Water is drawn from the tank whenever a faucet is opened, until the tank is drawn down to a predetermined minimum pressure, say 20 psig, whereupon the pressure switch kicks on, starting the pump to repressurize the tank to the 40 psig.
Downstream of the switch, the water, containing iron hydrate micelles, passes via line 10 to the control valve 11, which directs the flow of water into the tank 12 and, alternatively, to the backwash line 13 or to the service line 14. The tank 12 is provided with a dip tube 15 extending from top to bottom of the tank, with screens 17 and 16 at the top and bottom ends. The top of the dip tube 15 is directly connected to the valve 11, which directs flow in either direction in the line between either the service line 14 or the backwash line 13.
The tank 12 contains a bed 18 of particulate material such as pumice supported on a gravel layer 19, deep enough to cover the screen 16.
The flow entering the tank 12 from the line 10 is directed by the valve 11 to the top of the bed 18, and passes down through the bed to and through the gravel layer 19 and then enters the dip tube 15 via screen 16, whence it re-enters the valve 11 and is directed into line 14 to service.
When it is necessary to remove the collected iron hydrate sludge from the bed 18, the backwashing mode is adopted. The valve 11 is turned so that the influent flow is directed into the dip tube 15, out through the screen 16, and upwardly through the bed. This removes the collected iron hydrates, which pass through the screen 17 to be dumped by the backwash line 13.
FIG. 3 is a flow sheet showing the components of a municipal water system including an apparatus embodying the invention. The municipal water system shown in FIG. 3 receives water pumped by pump P from a reservoir or well (not shown) via line 50, around and through the injector-mixer 51 (shown in detail in FIG. 4) into the pressure holding tank 52. The aerated water downstream of the mixer 51 passes into line 54, which can be tapped by a line and valve (not shown, but as in FIG. 1) for sampling the aerated water. Such sampling permits monitoring of the amount of oxygen in the water. The water enters the pressure holding tank 52 via the line 54 at one end until the tank is under a predetermined maximum gauge pressure, say 75 psig, whereupon the pressure switch 59 kicks off to shut down the pump P. Water escapes from the tank 52 whenever a withdrawal is made, until the gauge registers a pressure of say 50 psig, whereupon the pressure switch 59 kicks on to restart the pump. The water enters the valve 60 and is directed, after passing through the filter, into the line 64 to service.
When the bed 68 needs to have the collected iron hydrates removed from the particulate material 68, the backwashing mode is adopted, as in FIG. 1. The value 60 is set so that the influent flow is directed in a reverse direction through the bed. This unloads the collected sludge, which is drawn through an upper screen (not shown) and thence dumped via the backwash line 63.
The injector-mixer in this instance uses air as the motive force to mix the air in the water. The injector-mixer 51 is shown in detail in FIG. 4. It has an air inlet 70 fed by air under pressure from line 71, the air being supplied by the compressor 72. The line 71 is provided with a valve 73 which can be moved into selected positions according to the amount of air required for the aeration. The air inlet 70 communicates with an orifice 74, sized according to air flow so as to create a vacuum into which water is drawn through the openings 78 defined by the supports 76. In the chamber 79 the air violently mixes with the water. Continuous with the chamber a diffuser 75 is carried on the four supports 76 anchored to the orifice housing 77 of the mixer 51. The air-water mixture enters the diffuser 75, and after leaving the diffuser is turbulently blended with the main stream of the water in passage 80.
In operation, water flow from line 50 is divided into main flow via passage 80 and flow drawn into the mixing chamber 79 via the openings defined by the supports 76. The air jet from the orifice 74 aspirates an amount of water controlled by the air velocity through the orifice, which in turn is controlled by the valve 73 and the air compressor 72, and also by the size of the orifice 74. A number of such injector-mixers may be inserted in the pipe 80 if the requirement exists and the pipe is sufficiently large.
Theoretically, 1 mg/liter of dissolved oxygen will oxidize 7 mg/liter of ferrous iron to the ferric state. This minimum amount would be required to convert the ferrous iron to the hydrated ferric oxides. However, more than this can be used to facilitate the conversion process. Example 14 shows that three times the theoretical amount gives virtually quantitative iron removal. In a case of high iron content, such as 25 mg/liter soluble iron, the oxygen content need not exceed 10 mg/liter. It is to be understood that oxygen gas may be substituted for air in all examples cited.
The following Examples, in the opinion of the inventor, represent preferred embodiments of the invention.
EXAMPLES 1 TO 12
In these Examples, the apparatus used for the test runs comprised a submerged pump, a Well-x-trol diaphragm pressure tank, and a filter bed. The Well-x-trol tank was provided with a pressure switch with a setting of 20 psig to initiate pump start, and a 40 psig setting for pump stop. Between these pressure limits, the pump had an average pumping rate of 19 gpm.
The pressure tank had a total capacity of 10 gallons per pumping cycle.
The particulate material used, as shown in Table I, was confined in a vertical tank 9 inches in diameter and 48 inches high. The tank was loaded to a depth of 26 inches with granular particulate material of the type indicated in the Table, such as, for instance in Example 1, pumice granules, and the particulate material held in place by a coarse gravel underlay 6 inches deep. The bed of particulate material acted to collect and remove the iron hydrate micelles present in the aerated water.
The tank was provided with a manual control valve permitting the water to pass through the bed to service or by backwash to drain.
The water as pumped from the well was analyzed, and found to contain 4.5 mg/liter of soluble iron. To prepare the system for service, the particulate bed was backwashed to remove excessive fines and orient the bed by particle size. With the filter control valve in the service position, water was then passed continuously through the bed, at the rate of 4 gpm/sq. ft., and samples were taken for iron analysis.
First, the test runs were carried out omitting the injector-mixer from the system and leading the well water directly to the pressure tank. Little or no reduction in the iron content of the water occurred in this series, as may be seen in Table I.
Next, the test runs were carried out with the injector-mixer. For aeration of the water, the injector-mixer was interposed between the pump and the pressure tank. The air intake through the suction tube was regulated to provide a dissolved oxygen content in the water of 1.2 mg/l. The treated water was then passed through the bed of particulate material, and again water samples were taken and analyzed for iron.
The effectiveness of the injector-mixer in removing the iron is apparent from Table 1. The most effective particulate material listed was pumice, which reduced the iron content to less than 0.05 mg/l. Extruded bentonite and kaolin were also very effective. Least effective were anthracite and silica sand No. 1, which were not rough but had a smooth, glasslike surface. Silica sand No. 2 showed a rough nodulous surface under microscopic examination, confirming the effect of the rough surface on the removal efficiency of the material.
TABLE I__________________________________________________________________________ Effluent water Aerated Non- 1.2 mg/l O.sub.2 aeratedExample No. Particulate Material Particle Size Surface Excoriates Fe-mg/l Fe-mg/l__________________________________________________________________________1 Pumice.sup.1 0.6 mm rough yes 0.05 4.2 porous2 Coke.sup.1 0.82 mm rough Slightly 1.5 4.3 porous3 Carbon.sup.2 1/16 inch rough yes 0.8 4.34 Anthracite.sup.1 0.8 mm smooth no 3.8 4.45 Sand No. 1.sup.1 0.7 mm smooth no 3.2 4.36 Sand No. 2.sup.1 1.0 mm rough no 1.75 4.47 Talc.sup.1 0.84 mm rough yes 0.5 4.38 Diatomaceous earth.sup.2 1/16 inch rough.sup.4 yes 0.5 4.39 Bentonite.sup.2 1/16 inch rough.sup.4 yes 0.3 4.410 Kaolin.sup.2 1/16 inch rough.sup.4 yes 0.3 4.411 Zeolite.sup.2 ion exchange 1/16 inch rough.sup.4 Slight 0.6 4.3 aluminum silicate12 Dolomite, partially 0.65 mm rough yes 0.07 4.3 calcined__________________________________________________________________________ .sup.1 media were screened to provide particle size as shown .sup.2 media were milled, wet extruded and dried .sup.3 water had a pH of 6.9 and contained 4.5 mg/liter of dissolved iron It was passed through the filter at a rate of 4 gpm/ft.sup.2. .sup.4 roughened by excoriation in use
EXAMPLES 13 TO 15
Using the same apparatus as Examples 1 to 12 with a pumice bed screened to provide pumice particles 0.6 mm in diameter, a series of runs were carried out at different flow rates, at different amounts of oxygen added through the injector-mixer, and at different pH's. In Example 13, the flow rate was varied. In Example 14, the amount of oxygen was varied, and in Example 15, the pH of the water was varied. The well water contained 4.5 mg/l of dissolved iron, and would require a theoretical dosage of 0.675 mg/l of dissolved oxygen to completely oxidize the contained ferrous iron.
The results obtained are shown in Table II.
TABLE II__________________________________________________________________________ Flow rate Aerated O.sub.2 pH of Fe-in effluentExample No. Particulate Material (gpm/ft.sup.2) (mg/l) well water (mg/l)__________________________________________________________________________13 Pumice- 2.8 1.4 6.9 0.02 ground and screened 3.7 1.4 6.9 0.05 0.6 mm 4.5 1.4 6.9 0.2 9.3 1.4 6.9 0.6 10.0 1.4 6.9 0.814 Pumice as above 4.5 0.7 6.9 0.2 4.5 1.0 6.9 0.2 4.5 1.2 6.9 0.1 4.5 1.6 6.9 0.04 4.5 2.0 6.9 0.0215 Pumice as above 4.5 1.2 6.25 .12 4.5 1.2 6.4 .08 4.5 1.2 6.6 .06 4.5 1.2 6.8 .02 4.5 1.2 7.1 0.05__________________________________________________________________________
The results for Example 13 show that a slower flow rate through the bed improves iron removal efficiency. A longer retention time in the bed promotes collection and removal of the iron hydrates and also prevents a breakthrough of iron-containing floc through the bed.
The results for Example 14 show that more than the theoretical amount of oxygen, about 0.7 mg/l, is beneficial in improving iron removal efficiency. Best results are obtained at three times the theoretical amount.
The results for Example 15 show that pH should exceed 6.4 for optimum iron removal efficiency. Best results are obtained at a pH of 6.8 and above.
EXAMPLE 16
Using the apparatus of Examples 1 to 12, a run was carried out using pumice with water containing 25 mg/liter of soluble iron, the maximum amount usually found in a water supply. The results obtained are shown in Table III.
TABLE III______________________________________ AeratedGrain Size 5.2 mg/l O.sub.2(mm) Surface Excoriates Fe-mg/l______________________________________pumice 0.6 rough yes 0.17 porous______________________________________
EXAMPLE 17
In this Example, the community water system shown in FIG. 3 was used, with a pump, a 4300-gallon pressure tank, and a 36"×6' bed of particulate material provided with the necessary 6" piping and controls for backwashing. A pressure range of 50 to 75 psig was maintained in the system. The particulate material used in the bed consisted of expanded perlite having an average particle size of 0.8 mm. Water containing 3.2 mg/l of iron was pumped to the pressure tank at a rate of 80 gpm and was aerated in 6" piping by using two small injector-mixers inserted as shown. The compressor was set to deliver air through the injectors to provide an O 2 content in the water of 1.2 mg/l. The system was well backwashed and allowed to come to equilibrium by water withdrawal over a two-day period. At the end of this time, the pH was found to be 7.0 and iron reduced to 0.12 mg/l. Water withdrawal rates continued at about 3000 gallons per day; backwashing to remove the collected iron-containing sludge was carried out once weekly.
EXAMPLE 18
Using the same apparatus as in Examples 1 to 12, a suction pump was substituted for the submersible pump. The suction pump was fitted with a snifter valve provided with a spring-loaded check valve at the suction connection of the pump. A screw protruding into the air stream controlled flow rate of air into the water. An injector-mixer was inserted downstream of the pump, between the pump and the pressure tank. The suction inlet of the injector-mixer for air intake was eliminated. The analysis of the effluent water showed an iron content of 0.5 mg/l. | A process is provided for removing impurities such as iron compounds from water, which comprises the steps of:
(1) colloidalizing the iron compounds in water under conditions of high shear and decompression/compression to finely divide existing insoluble iron hydrates, and by dissolution in the water of air in sufficient amount to oxidize and form colloidally dispersed iron hydrates from the dissolved iron present, thereby providing substantially all of the iron in the form of micelles having a surface charge;
(2) maintaining the water under a pressure within the range from about 10 to 500 psig;
(3) then passing the water under a pressure within said range through a mass of particulate material having a surface charge capable of attracting, removing, and collecting the dispersed iron hydrates; and
(4) recovering water containing less iron than the starting water, and preferably less than 0.3 PPM of iron.
The iron hydrates collected throughout the mass of particulate material are non-adherent and can be easily removed by backwashing the filter. | 8 |
FIELD OF THE INVENTION
[0001] This invention relates to an irrigation valve for controlling the flow of water through piping of an irrigation system. More particularly, this invention relates to an irrigation valve with improved operation at low water flows.
BACKGROUND OF THE INVENTION
[0002] Flow control valves are a well known and integral part of most irrigation systems. A typical example can be seen in U.S. Pat. No. 6,394,413 to Lohde, et al, herein incorporated by reference.
[0003] These valves control the flow of water through an upstream pipe and thereby turn sprinklers fed by the pipe on and off. Such valves are usually remotely actuated by control signals sent from an automated irrigation controller. Often, these control signals are electric impulses sent from the controller to a solenoid in the valve which ultimately controls whether the valve is open or closed.
[0004] Pilot-activated diaphragm-operated valves for use in irrigation systems are well known. One example can be seen in U.S. Pat. No. 3,336,843, herein incorporated by reference.
[0005] This style of valve has a closure member with a sealing surface which moves against or away from an annular seat to close or open the valve, respectively. Integral to the closure member is a diaphragm positioned to seal off an upper portion of the valve. When the valve is to be opened, the fluid pressure is relieved by bleeding fluid out of the diaphragm chamber through a manual valve or a remotely operated solenoid valve. Relieving this pressure allows the closure member to move upwards as water passes through the valve.
[0006] To save on manufacturing expenses and also to avoid the negative effects of material warpage and deformation, the closure member must be molded in such a way that it has a constant wall thickness, resulting in open channels or spaces, commonly called “material savers.” What has been discovered, however, is that over time, the diaphragm may extrude into these channels or spaces. This extrusion increases tension on the diaphragm, preventing valve closure at low water flows.
[0007] Some prior art valves available on the market today prevent the diaphragm extrusion into the closure member by providing a separate plastic insert into the inner channel of the guide washer. While this method prevents diaphragm extrusion, it presents increased manufacturing expense and difficulties by presenting another plastic part to design and injection mold. Further, the manufacturing conditions for both the closure member and the insert must be highly controlled and precise, otherwise the insert will fit poorly within the closure member, risking inefficient or faulty valve operation.
[0008] Therefore, what is needed is a single piece closure member that is easily manufactured, yet also prevents diaphragm extrusion within the closure member.
OBJECTS AND SUMMARY OF THE INVENTION
[0009] It is an object of the present invention to provide an improved valve that closes properly under low flow water conditions.
[0010] It is a further object of the present invention to provide an improved valve that continues to close at low water flows over an extended period of time.
[0011] The present invention seeks to address the above described problems and others not specifically enumerated here by providing a valve having an improved closure member, the preferred embodiment of which are described below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0012] FIG. 1 is a cross sectional view of an irrigation valve of the prior art;
[0013] FIG. 2 is a cross sectional view of an irrigation valve as shown in FIG. 1 with a diaphragm extruded into a closure member;
[0014] FIG. 3 is a cross sectional view of one embodiment of the present invention;
[0015] FIG. 4 is a plan view of a valve diaphragm of the prior art;
[0016] FIG. 5 is a plan view of a typical valve diaphragm assembly of the prior art; and
[0017] FIG. 6 is a plan view of one embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0018] FIGS. 1 and 2 illustrate a prior art irrigation valve 100 in the closed position. This irrigation valve 100 includes a water inlet port 114 , a water outlet port 115 , and a guide washer 102 that includes a sealing surface 103 . Typically the sealing surface 103 is made from a rubber or other resilient material.
[0019] The valve is actuated by a solenoid 112 that is connected to a solenoid plunger 108 which controls the opening and closing of a discharge port 107 . In the closed position, the solenoid plunger 108 blocks a passage 150 that otherwise connects a diaphragm chamber 109 (located above a diaphragm 101 ) to the discharge port 107 and to the valve water outlet port 115 .
[0020] The valve assembly 120 seals off the diaphragm chamber 109 from the lower portion of the valve. As seen in FIG. 5 , the valve assembly 120 is made up of a diaphragm retaining cap 117 which sits over a diaphragm 101 . Beneath the diaphragm sits a guide washer 102 having an inner circular channel 110 . Retained in the guide washer 102 is a sealing surface 103 . The sealing surface 103 is secured to the guide washer 102 with a valve washer 118 and metering insert 106 .
[0021] The diaphragm 101 is typically composed of a semi elastic material such as rubber. Such elastic material allows the diaphragm to flex as the valve assembly 120 rises up to an open position and down to a closed position. The diaphragm is secured in the valve 100 between the upper portion 205 of the valve 100 and the lower portion 207 of the valve 100 . These two halves are secured together with screws (not shown). As seen in FIGS. 1 and 2 , a properly secured diaphragm creates the upper diaphragm chamber 109 .
[0022] As best seen in FIGS. 1 and 2 , metering pin 105 is located within the center of valve assembly 120 . The clearance 104 between the metering insert 106 and metering pin 105 allows water to enter into the diaphragm chamber 109 . The diameter of the metering pin 105 may be changed to let varying amounts of water into the diaphragm chamber 109 , thus controlling the pressure within the diaphragm chamber 104 .
[0023] In the closed position, the water pressure in the diaphragm chamber 109 is equal to the water pressure in the valve through water inlet port 114 . In contrast, the water pressure of diaphragm chamber 109 is much less than the pressure of water entering through the water inlet port 114 when the valve is set to the open position as discussed below. The pressure is lower due to the pressure drop that occurs when the water flows through the clearance 104 .
[0024] In operation, a water supply is connected to water inlet port 114 , and further portions of an irrigation system are connected to water outlet port 115 . When the solenoid 112 is un-energized, the solenoid plunger 108 is biased to cover and seal the discharge port 107 . As water enters from the water inlet port 114 , it travels through the clearance 104 of the metering insert 106 , into the diaphragm chamber 109 . Simultaneously, due to losses resulting from flow of water, the pressure of the inlet port 114 drops while passing between the seal surface 103 and valve seat 121 , causing an annular area of low pressure 152 , which helps the diaphragm assembly 120 to move downwards. Pressure builds within the diaphragm chamber 109 until it approaches equalization with the water pressure coming in from water inlet port 114 . Typical inlet pressure is about 60 psi. With the help of the spring 111 , the diaphragm assembly continues downwards until the sealing surface 103 makes contact with the valve seat 121 .
[0025] In the shut position, the pressure within the diaphragm chamber 109 is equal to the pressure of the inlet 114 , but the overall force on the diaphragm assembly 120 is downwards. This is due to the fact that the pressure in the diaphragm chamber 109 is exerting its effect over a larger surface area of the diaphragm assembly 120 , than the pressure in the inlet 114 . This downward resultant force prevents the diaphragm assembly 120 from being pushed up from the water pressure of the inlet 114 . As a result, the sealing surface 103 of the diaphragm assembly 120 remains seated on the valve seat 121 , preventing passage of the inlet water through the valve.
[0026] When the solenoid 112 is energized, the solenoid plunger 108 lifts and thus allows water from the diaphragm chamber 109 to pass through the discharge port 107 and out to the water outlet port 115 . The open discharge port 107 thus causes pressure in the diaphragm chamber 109 to drop. As a result, the water from the water inlet port 114 pushes up on the valve assembly 120 , which compresses valve spring 111 and unseats the sealing surface 103 from the valve seat 121 . With the valve pushed upwards, away from its valve seat 121 , water may freely pass from the water inlet port 114 , through valve 100 , and out water outlet port 115 .
[0027] FIG. 2 illustrates a problem common to prior art irrigation valves. To improve manufacturability and reduce costs, guide washer 102 is formed with an inner circular channel 110 . This inner circular channel 110 is covered by diaphragm 101 . Due to factory manufacturing conditions, air is often trapped between the diaphragm 101 and this inner circular channel 110 .
[0028] When the valve 100 is in the closed position, pressure builds in the diaphragm chamber 109 . Since air compresses under pressure, unlike water, a portion of the diaphragm 101 a is thus pushed or extruded into the circular channel 110 . Consequently, the peripheral edges of the diaphragm 101 become stretched and taut, making it more difficult for the valve to close.
[0029] When flow into the valve 100 is medium to high (typically about 5-30 gallons per minute), the additional closing force generated by the low pressure region in the annular space 152 required to seat the valve seal 103 is available, in spite of the extruded diaphragm, and the valve assembly 120 properly closes. But when flow into the valve 100 is low (typically less than about 5 gallons per minute), the resulting low pressure region generated in the annular space 152 is insufficiently low enough to fully seat the sealing surface 103 onto the valve seat 121 .
[0030] In some circumstances, the faulty valve assembly 120 remains open about 0.02-0.05 inches, which is enough for the valve 100 to flow 1-4 gallons per minute, never fully shutting off. And, over time, the diaphragm 101 becomes increasingly stretched, as greater portions 101 a of the diaphragm 101 extrude into the circular channel 110 .
[0031] The present invention seeks to avoid the above problem by presenting a guide washer 201 which prevents extrusion of the diaphragm 101 into the circular channel 110 .
[0032] FIG. 6 illustrates one embodiment of a valve assembly 202 containing a spoked guide washer 201 . The spoked guide washer 201 is circular in shape, having an inner circular channel interrupted by multiple fins 203 . Each fin 203 extends to the bottom of the inner channel and is level with the surface of the spoked guide washer 201 .
[0033] The positioning and the numbering of fins 203 are such that they prevent the diaphragm 101 from extruding into the gaps of the inner channel of the spoked guide washer 201 . Although air may be present in gaps of the inner channel, the spokes maintain the relative position of the diaphragm 101 and thus better ensure the valve functionality (e.g. closure) at low water flows.
[0034] FIG. 3 illustrates the spoked guide washer's 201 positioning within the improved valve 200 . With higher reliability, the improved valve 200 may be used for a wider variety of irrigation uses, such as drip irrigation.
[0035] It is known in the art that an injection molding process is best used when the design of the molded part ensures that even cooling of the molten plastic occurs. If cooling differentials occur, then the molded plastic article will likely encounter sink problems that distort or warp the molded article shape from it's intended original form.
[0036] The design of spoked guide washer 201 allows the article to cool evenly by virtue of the spaces between fins 203 , thus ensuring that the guide washer 201 maintains its original intended shape.
[0037] In a preferred embodiment, the present invention prevents diaphragm extrusion with a spoked guide washer 201 , keeping design and manufacturing costs low, while also reducing possible complication associated with additional parts.
[0038] An alternative embodiment of the present invention (not pictured) includes spoked bars within the guide washer wherein the bars are, radially positioned and flush with the upper surface. Like the previous embodiment's fins, the bars help support the diaphragm while preventing extrusion into the inner channel of the guide washer. Unlike the fins, the bars do not extend downward to the bottom of the inner channel, yet still provide the same extrusion resistant benefits.
[0039] Although the invention has been described in terms of particular embodiments and applications, one of ordinary skill in the art, in light of this teaching, can generate additional embodiments and modifications without departing from the spirit of or exceeding the scope of the claimed invention. Accordingly, it is to be understood that the drawings and descriptions herein are proffered by way of example to facilitate comprehension of the invention and should not be construed to limit the scope thereof. | The present invention illustrates an irrigation valve that operates at low flows by providing a guide washer of the valve assembly that prevents diaphragm extrusion. Specifically, the circular channel area of a guide washer of the valve includes spoke-like fins. These fins keep the diaphragm from extruding into the open channel over time, while allowing for easy guide washer manufacturing. | 5 |
FIELD
[0001] The present application relates to fuel vapor purging in a hybrid vehicle.
BACKGROUND AND SUMMARY
[0002] Hybrid vehicles, such as plug-in hybrid vehicles, may have two modes of operation: an engine-off mode and an engine-on mode. While in the engine-off mode, power to operate the vehicle may be supplied by stored electrical energy. While in the engine-on mode, the vehicle may operate using engine power. By switching between electrical and engine power sources, engine operation times may be reduced, thereby reducing overall carbon emissions from the vehicle. However, shorter engine operation times may lead to insufficient purging of fuel vapors from the vehicle's emission control system. Additionally, refueling and emission control system leak detection operations that are dependent on pressures and vacuums generated during engine operation may also be affected by the shorter engine operation times in hybrid vehicles.
[0003] Various strategies have been developed to address fuel vapor control and management in hybrid vehicle systems. Example approaches include separating storage of refueling vapors from storage of diurnal vapors by adding a fuel tank isolation valve (FTIV) between a fuel tank and a fuel vapor retaining canister, and allowing refueling vapors to the canister during refueling events, and engine-on purging methods. The separation of diurnal and refueling vapors allows a pressure to be generated in the fuel tank, while application of alternative vacuum sources allows a vacuum to be generated in the canister.
[0004] One example approach for fuel vapor management is shown by Ito el al. in U.S. Pat. No. 6,557,401. Therein, leak detection of fuel vapor recovery system components is performed in two stages. First the fuel tank is sealed and a change in fuel tank pressure is measured over time. Next, a vacuum is applied to the canister. Presence of leaks is determined based on changes in the fuel tank pressure and the canister pressure over time.
[0005] Another example approach is shown by Takagi et al. in U.S. Pat. No. 6,761,154. Therein, leak detection is performed by operating a pump to apply a vacuum on the carbon canister, followed by monitoring a change in canister pressure over time. A valve disposed between the fuel tank and the carbon canister is then opened to apply the vacuum to the fuel tank, followed by monitoring a change in fuel tank pressure over time. Presence of leaks may be determined based on changes in canister pressure and fuel tank pressure over time
[0006] However, the inventors herein have recognized potential issues with these approaches. As one example, these approaches fail to address the transitory nature of pressure and vacuum accumulation in a hybrid vehicle system due to infrequent and irregular engine operation. For example, the shorter duration of engine operation in hybrid vehicles may lead to lower amounts of vacuum being generated during an engine-on mode, such that insufficient vacuum may be present in the fuel tank for a subsequent leak detection operation. As a result, there may not be sufficient pressure and/or vacuum for detecting leaks in both the fuel tank and the carbon canister. Since leak detection in the fuel tank in the above approaches is tied to leak detection in the carbon canister, insufficient pressure and/or vacuum may lead to incomplete fuel vapor recovery system leak detection. Also, operation of an external dedicated pump to generate vacuum and/or pressure for leak detection may increase system cost and power consumption.
[0007] The above issues may be at least partly addressed by a method of monitoring a vehicle fuel vapor recovery system coupled to an engine intake, said fuel vapor recovery system including a fuel tank coupled to a canister via a fuel tank isolation valve, the canister coupled to the engine intake via a canister purge valve, the canister further coupled to a vacuum accumulator via a vacuum accumulator valve. The method may comprise, under a first condition, applying a pressure on the fuel tank before applying a pressure on the canister; and under a second condition, applying a pressure on the canister before applying a pressure on the fuel tank; and under the first or second condition, indicating degradation based on a change in a fuel vapor recovery system pressure value upon pressure application. In one example, a fuel vapor recovery system for a hybrid vehicle may comprise a fuel tank coupled to fuel vapor retaining device (such as a carbon canister) via a fuel tank isolation valve (FTIV). The canister may be coupled to the engine intake via a canister purge valve (CPV). The canister may be further coupled to a vacuum accumulator via a vacuum accumulator valve (VAV). As such, the FTIV may be maintained in a closed state during vehicle operation and may be selectively opened during refueling and diurnal vapor purging conditions. By maintaining the FTIV closed, the fuel vapor circuit may be divided into a canister side and a fuel tank side. Refueling vapors may be retained in the canister on the canister side of the circuit while diurnal vapors may be retained in the fuel tank on the fuel tank side of the circuit.
[0008] A first pressure sensor may be coupled to the fuel tank to estimate a pressure of the fuel tank side of the circuit, while a second pressure sensor may be coupled to the canister to estimate a pressure of the canister side of the circuit. Based on input from various sensors, such as the pressure sensors, and further based on vehicle operating conditions, a controller may adjust various actuators, such as the VAV, the CPV, the FTIV, and a canister vent valve (CVV), to enable fuel tank refueling, purging of stored fuel vapors, and leak detection in the fuel vapor recovery system.
[0009] In one example, during leak detection, an order of monitoring components of the fuel vapor recovery system may be adjusted based on an amount of pressure and/or vacuum available for the leak detection in either of the carbon canister or the fuel tank. For example, if sufficient pressure and/or vacuum is not available in the fuel tank for leak detection, vacuum from the vacuum accumulator may be applied to the carbon canister by opening the VAV. In this case, first the carbon canister may be checked for leaks, then the operation of the FTIV may be monitored, and then the fuel tank may be tested for leaks. In comparison, when the fuel tank does have sufficient pressure and/or vacuum for leak detection, the order of leak detection may be changed, wherein first the fuel tank may be tested for leaks, then the operation of the FTIV may be determined, and finally the carbon canister may be checked for leaks.
[0010] In one example, leak detection may involve monitoring a change in fuel tank pressure and/or a canister pressure over time. For example, leaks may be identified based on a rate of change in pressure during the vacuum/pressure application, or based on difference before and after vacuum/pressure application. In another example, leak detection may be based on temperature and pressure changes in the fuel tank.
[0011] In this way, by adjusting an order of application of vacuum and/or pressure on fuel vapor recovery system components based on availability of vacuum and/or pressure, leak detection may be performed on all the components of the system even when the duration of the engine-on operation varies in the hybrid vehicle. Additionally, leak detection in the components may be decoupled from each other based on the amount of pressure and/or vacuum available. By decoupling leak detection in a first component, such as the fuel tank, from leak detection in a second component, such as the canister, a more robust leak detection routine may be possible.
[0012] It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 shows a schematic depiction of a hybrid vehicle.
[0014] FIG. 2 shows an example embodiment of the fuel system and fuel vapor recovery system of FIG. 1 .
[0015] FIG. 3 shows a high level flow chart for operating the fuel vapor recovery system of FIG. 2 .
[0016] FIG. 4 shows a high level flow chart for operating the fuel vapor recovery system during a refueling event.
[0017] FIG. 5 shows a high level flow chart for operating the fuel vapor recovery system during a purging event.
[0018] FIGS. 6-8 show high level flow charts for performing leak detection operations on the fuel vapor recovery system of FIG. 2 .
[0019] FIGS. 9-11 show maps depicting example fuel tank and/or canister pressures which may occur during leak detection operations.
[0020] FIG. 12 shows a map depicting example changes in fuel tank temperature which may occur during leak detection operations.
DETAILED DESCRIPTION
[0021] The following description relates to a fuel vapor recovery system for a hybrid vehicle, such as the vehicle system of FIG. 1 , and a method of monitoring flow of fuel vapors and/or air though the fuel vapor recovery system. As shown in FIG. 2 , the fuel vapor recovery system may include a fuel tank isolated from a canister by a fuel tank isolation valve (FTIV), the canister further coupled to an engine intake by a canister purge valve (CPV). In this way, refueling vapors may be stored in the canister while diurnal vapors are retained in the fuel tank, dividing the fuel vapor circuit into a canister side and a fuel tank side. A vacuum accumulator may be included in the fuel vapor recovery system to provide a vacuum source to the canister. The vacuum accumulator may be configured to generate and store vacuum during engine-on conditions and engine-off conditions, such as from the engine and/or from a brake booster pump. A controller may receive signals from various sensors including pressure, temperature, fuel level, and refueling door position sensors, and accordingly regulate actuators, including various valves of the fuel vapor recovery system, by performing various routines during vehicle operation, such as refueling, fuel vapor purging, and leak detection, as shown in FIGS. 3-8 . Example changes in system pressures and temperatures, as detected by various sensors in the fuel vapor recovery system, are depicted in the maps of FIGS. 9-12 . By applying inter-related strategies, engine-on and engine-off vehicle operations, refueling, fuel vapor purging, and leak detection operations may be better coordinated, thereby improving fuel vapor management in hybrid vehicles.
[0022] Referring to FIG. 1 , the figure schematically depicts a vehicle with a hybrid propulsion system 10 . Hybrid propulsion system 10 includes an internal combustion engine 20 coupled to transmission 16 . Transmission 16 may be a manual transmission, automatic transmission, or combinations thereof. Further, various additional components may be included, such as a torque converter, and/or other gears such as a final drive unit, etc. Transmission 16 is shown coupled to drive wheel 14 , which may contact a road surface.
[0023] In this example embodiment, the hybrid propulsion system also includes an energy conversion device 18 , which may include a motor, a generator, among others and combinations thereof. The energy conversion device 18 is further shown coupled to an energy storage device 22 , which may include a battery, a capacitor, a flywheel, a pressure vessel, etc. The energy conversion device may be operated to absorb energy from vehicle motion and/or the engine and convert the absorbed energy to an energy form suitable for storage by the energy storage device (in other words, provide a generator operation). The energy conversion device may also be operated to supply an output (power, work, torque, speed, etc.) to the drive wheel 14 and/or engine 20 (in other words, provide a motor operation). It should be appreciated that the energy conversion device may, in some embodiments, include a motor, a generator, or both a motor and generator, among various other components used for providing the appropriate conversion of energy between the energy storage device and the vehicle drive wheels and/or engine.
[0024] The depicted connections between engine 20 , energy conversion device 18 , transmission 16 , and drive wheel 14 may indicate transmission of mechanical energy from one component to another, whereas the connections between the energy conversion device 18 and the energy storage device 22 may indicate transmission of a variety of energy forms such as electrical, mechanical, etc. For example, torque may be transmitted from engine 20 to drive the vehicle drive wheel 14 via transmission 16 . As described above energy storage device 22 may be configured to operate in a generator mode and/or a motor mode. In a generator mode, system 10 may absorb some or all of the output from engine 20 and/or transmission 16 , which may reduce the amount of drive output delivered to the drive wheel 14 , or the amount of braking torque from brake system 30 , which includes brake booster 34 and brake booster pump 32 , to the drive wheel 14 . Such operations may be employed, for example, to achieve efficiency gains through regenerative braking, increased engine efficiency, etc. Further, the output received by the energy conversion device may be used to charge energy storage device 22 . Alternatively, energy storage device 22 may receive electrical charge from an external energy source 24 , such as a plug-in to a main electrical supply. In motor mode, the energy conversion device may supply mechanical output to engine 20 and/or transmission 16 , for example by using electrical energy stored in an electric battery.
[0025] Hybrid propulsion embodiments may include full hybrid systems, in which the vehicle can run on just the engine, just the energy conversion device (e.g. motor), or a combination of both. Assist or mild hybrid configurations may also be employed, in which the engine is the primary torque source, with the hybrid propulsion system acting to selectively deliver added torque, for example during tip-in or other conditions. Further still, starter/generator and/or smart alternator systems may also be used.
[0026] From the above, it should be understood that the exemplary hybrid propulsion system is capable of various modes of operation. For example, in a first mode, engine 20 is turned on and acts as the torque source powering drive wheel 14 . In this case, the vehicle is operated in an “engine-on” mode and fuel is supplied to engine 20 from fuel system 100 (depicted in further detail in FIG. 2 ). Fuel system 100 includes a fuel vapor recovery system 110 to store fuel vapors and reduce emissions from the hybrid vehicle propulsion system 10 .
[0027] In another mode, the propulsion system may operate using energy conversion device 18 (e.g., an electric motor) as the torque source propelling the vehicle. This “engine-off” mode of operation may be employed during braking, low speeds, while stopped at traffic lights, etc. In still another mode, which may be referred to as an “assist” mode, an alternate torque source may supplement and act in cooperation with the torque provided by engine 20 . As indicated above, energy conversion device 18 may also operate in a generator mode, in which torque is absorbed from engine 20 and/or transmission 16 . Furthermore, energy conversion device 18 may act to augment or absorb torque during transitions of engine 20 between different combustion modes (e.g., during transitions between a spark ignition mode and a compression ignition mode).
[0028] The various components described above with reference to FIG. 1 may be controlled by a vehicle control system 40 , which includes a controller 12 with computer readable instructions for carrying out routines and subroutines for regulating vehicle systems, a plurality of sensors 42 , and a plurality of actuators 44 . Select examples of the plurality of sensors 42 and the plurality of actuators 44 are described in further detail below, in the description of fuel system 100 .
[0029] FIG. 2 shows an example embodiment 200 of the fuel system 100 and fuel vapor recovery system 110 of FIG. 1 . Engine 20 , coupled to a fuel system 100 , may include a plurality of cylinders (not shown). Engine 20 may receive intake air through intake manifold 60 which may lead to an exhaust passage (not shown) that routes exhaust gas to the atmosphere (as indicated by arrows). It will be appreciated that the engine intake and exhaust manifolds may be additionally coupled to an emission control device and/or a boosting device.
[0030] Fuel system 100 may include a fuel tank 120 coupled to a fuel pump system for pressurizing fuel delivered to the injectors of engine 20 (not shown). It will be appreciated that fuel system 100 may be a return-less fuel system, a return fuel system, or various other types of fuel system. Vapors generated in fuel system 100 may be routed to a fuel vapor recovery system 110 via a first conduit, vapor line 112 , before being purged to intake manifold 60 via a second conduit, purge line 118 .
[0031] The fuel tank 120 may hold a plurality of fuel blends, including fuel with a range of alcohol concentrations, such as various gasoline-ethanol blends, including E10, E85, gasoline, etc., and combinations thereof. As depicted in FIG. 2 , fuel tank 120 includes a fuel level sensor 122 which may comprise a float connected to a variable resistor. Alternatively, other types of fuel level sensors may be used. Fuel level sensor 122 sends fuel level input signals to controller 12 .
[0032] Fuel tank 120 also includes a refueling line 116 , which is a passageway between the refueling door 126 , which includes a refueling valve (not shown) on the outer body of the vehicle and the fuel tank, wherein fuel may be pumped into the vehicle from an external source during a refueling event. Refueling door sensor 114 coupled to refueling door 126 may be a position sensor and send input signals of a refueling door open or closed state to controller 12 . Refueling line 116 and vapor line 112 may each be coupled to an opening in fuel tank 120 ; therein fuel tank 120 has at least two openings.
[0033] As noted above, vapor line 112 is coupled to the fuel tank for routing of fuel vapors to a fuel vapor canister 130 of the fuel vapor recovery system 110 . It will be appreciated that fuel vapor recovery system 110 may include one or more fuel vapor retaining devices, such as one or more of a fuel vapor canister 130 . Canister 130 may be filled with an adsorbent capable of binding large quantities of vaporized hydrocarbons (HCs). In one example, the adsorbent used is activated charcoal.
[0034] Canister 130 may receive fuel vapors from fuel tank 120 through vapor line 112 , as vapor line 112 is connected at an opposing end to an opening in canister 130 . Canister 130 includes two additional openings, wherein a vent 136 and a purge line 118 are coupled, such that canister 130 has three openings. While the depicted example shows a single canister, it will be appreciated that in alternate embodiments, a plurality of such canisters may be connected together.
[0035] Opening of vapor line 112 is regulated by a fuel tank isolation valve (FTIV) 124 . In an alternate embodiment FTIV 124 may be mounted directly to fuel tank 120 at the attachment point of vapor line 112 . As such, during vehicle operation, FTIV 124 may be maintained in a closed state, such that refueling vapors may be stored in the canister on the canister side of the fuel vapor circuit and diurnal vapors may be retained in the fuel tank on the fuel tank side of the fuel vapor circuit. FTIV 124 may be operated on by controller 12 in response to a refueling request or an indication of purging conditions. In these instances, FTIV 124 may be opened to allow diurnal vapors to enter the canister and relieve pressure in the fuel tank. Additionally, FTIV 124 may be operated on controller 12 to perform specific steps of leak detection, such as applying a pressure (positive pressure or vacuum) from fuel tank 120 to canister 130 during a first leak detection condition, or applying a vacuum from canister 130 to fuel tank 120 during a second leak detection condition (described in further detail in FIGS. 6-8 ). In one example, FTIV 124 may be a solenoid valve and operation of FTIV 124 may be regulated by the controller by adjusting a duty cycle of the dedicated solenoid (not shown).
[0036] A first fuel tank pressure sensor, such as a fuel tank pressure transducer (FTPT) 128 , may be coupled to fuel tank 120 to provide an estimate of a fuel tank pressure. For example, FTPT 128 may be included in the top portion of fuel tank 120 . In an alternate embodiment, FTPT 128 may be coupled to vapor line 112 on the fuel tank side of the fuel vapor circuit. Additionally, fuel tank 120 may include a temperature sensor 140 to provide an estimate of a fuel tank temperature. Temperature sensor 140 may be coupled to FTPT 128 , as depicted in FIG. 2 . In an alternate embodiment, temperature sensor 140 may be coupled to the fuel tank in a distinct location from FTPT 128 . Each of pressure (P FT ) and temperature (T FT ) signals from FTPT 128 and temperature sensor 140 , respectively, are received by controller 12 .
[0037] Fuel vapor recovery system 110 may communicate with the atmosphere through vent 136 , extending from canister 130 . Canister vent valve (CVV) 132 may be located along vent 136 , coupled between canister 130 and the atmosphere, and may adjust flow of air and vapors between fuel vapor recovery system 110 and the atmosphere. Operation of the CVV 132 may be regulated by a canister vent solenoid (not shown). Based on whether the fuel vapor recovery system is to be sealed or not sealed from the atmosphere, the CVV may be closed or opened. Specifically, controller 12 may energize the canister vent solenoid to close CVV 132 and seal the system from the atmosphere, such as during leak detection conditions.
[0038] In contrast, when the canister vent solenoid is at rest, the CVV 132 may be opened and the system may be open to the atmosphere, such as during purging conditions. Further still, controller 12 may be configured to adjust the duty cycle of the canister vent solenoid to thereby adjust the pressure at which CVV 132 is relieved. In one example, during a refueling vapor storing operation (for example, during a fuel tank refilling and/or while the engine is not running), the canister vent solenoid may be de-energized and the CVV may be opened so that air, stripped of fuel vapor after having passed through the canister, can be pushed out to the atmosphere. In another example, during a purging operation (for example, during a canister regeneration and while the engine is running), the canister vent solenoid may be de-energized and the CVV may be opened to allow a flow of fresh air to strip the stored vapors of the activated charcoal. Additionally, controller 12 may command CVV 132 to be intermittently closed, by adjusting operation of the canister vent solenoid, to diagnose reverse flow through the fuel vapor recovery system. In yet another example, during leak detection, the canister vent solenoid may be energized to close CVV 132 , while CPV 134 and FTIV 124 are also closed, such that the canister side of fuel vapor recovery circuit is isolated. In this way, by commanding the CVV to be closed, the controller may seal the fuel vapor recovery system from the atmosphere.
[0039] Fuel vapors released from canister 130 , for example during a purging operation, may be directed into intake manifold 60 via purge line 118 . The flow of vapors along purge line 118 may be regulated by canister purge valve (CPV) 134 , coupled between the fuel vapor canister and the engine intake. In one example, CPV 134 may be a ball check valve, although alternative check valves may also be used. The quantity and rate of vapors released by the CPV may be determined by the duty cycle of an associated solenoid (not shown). As such, the duty cycle of the canister purge valve solenoid may be determined by the vehicle's powertrain control module (PCM), such as controller 12 , responsive to engine operating conditions, including, for example, an air-fuel ratio. By commanding the canister purge valve to be closed, the controller may seal the fuel vapor recovery system from the engine intake.
[0040] An optional canister check valve 136 may also be included in purge line 118 to prevent intake manifold pressure from flowing gases in the opposite direction of the purge flow. As such, the check valve may be necessary if the canister purge valve control is not accurately timed or the canister purge valve itself can be forced open by a high intake manifold pressure (such as, during boosted conditions). An estimate of the manifold absolute pressure (MAP) may be obtained from a MAP sensor (not shown) coupled to engine intake manifold 60 , and communicated with controller 12 . As such, check valve 136 may only permit the unidirectional flow of air from canister 130 to intake manifold 60 . In the event of high pressure air entering the purge line from intake manifold 60 , canister check valve 136 may close, thereby preventing the pressure in canister 130 from exceeding design limits. While the depicted example shows the canister check valve positioned between the canister purge valve and the intake manifold, in alternate embodiments, the check valve may be positioned before the purge valve. A second canister pressure sensor, such as canister pressure transducer (CPT) 138 , may be included in purge line 118 , coupled between canister 130 and CPV 134 to provide an estimate of a canister pressure. In alternate embodiments the CPT may be coupled to the vent between the canister and the CVV, or may be coupled to the vapor line between the canister and the fuel tank on the canister side of the fuel vapor circuit. Signals indicating canister pressure (Pc) are received by controller 12 .
[0041] Fuel vapor recovery system 110 also includes vacuum accumulator 202 coupled to fuel vapor canister 130 . In one example, vacuum accumulator 202 may be coupled through vacuum line 208 to purge line 118 , between canister 130 and the CPV 134 . In other example embodiments, the vacuum line may be coupled to the vapor line between the canister and the FTIV. Application of vacuum from the vacuum accumulator to the canister through vacuum line 208 is regulated by opening or closing vacuum accumulator valve (VAV) 204 , as commanded by controller 12 . VAV 204 may be selectively opened by controller 12 during emission leak detection operations, such as when insufficient engine-off natural vacuum is available, to provide additional vacuum for leak detection. For example, VAV 204 may be selectively opened during a secondary leak detection subroutine implemented under a condition wherein the absolute pressure of the fuel tank is less than a threshold, as further elaborated in FIG. 9 .
[0042] In one embodiment, vacuum accumulator 202 may be coupled to intake manifold 60 through conduit 206 , and may accumulate vacuum when the hybrid vehicle is operated in the engine-on mode. That is, the accumulator may store an amount of engine vacuum for later use. Additionally, or optionally, a venturi 302 may be coupled to vacuum accumulator 202 by venturi vacuum line 304 . The venturi may be mounted at various locations on the body of the hybrid vehicle that receive air or exhaust flow during vehicle motion and operation. For example, the venturi may be mounted on the underside of the vehicle body. In another example, venturi 302 may be coupled to the exhaust manifold, for example along the tailpipe, such that vacuum may be generated due to the flow of exhaust through the venturi. In yet another example, as depicted, venturi 302 may be mounted in the exhaust pathway of a brake booster pump 32 coupled to a brake booster 34 of the vehicle brake system 30 . Herein, during brake application, vacuum may be generated due to operation of the brake booster pump and flow of brake booster pump exhaust through the venturi. In one example, by coupling the venturi to the exhaust pathway of the brake booster pump, rather than directly coupling the vacuum accumulator to the brake booster pump, the brake booster pump may not be exposed to fuel vapors. In still other embodiments, vacuum accumulator 202 may be directly coupled to brake booster pump 32 , wherein vacuum may be generated by operating the brake pump, and stored in the vacuum accumulator for use in leak detection routines.
[0043] Controller 12 may be configured to regulate various operations of the fuel vapor recovery system by receiving signals from sensors, such as pressure, temperature, and position sensors, and commanding on actuators, such as opening and closing of valves or the refueling door. For example, controller 12 may carry out various routines for leak detection, refueling, and fuel vapor purging, as shown in FIGS. 4-8 . Specifically, the various routines for the fuel vapor recovery system may be better coordinated by controller 12 , for example, by performing a higher-level vapor recovery system routine, as shown in FIG. 3 , which may strategically implement each of the various routines depending on the operating conditions of the vehicle, such as engine-on or engine-off operations, and pressure and temperature inputs from sensors. For example, if a refueling routine is implemented, controller 12 may disable a purging routine.
[0044] An example higher-level vapor recovery system routine 300 is depicted in FIG. 3 . Herein, at 302 it may be determined whether the vehicle is on or off, that is, whether or not the vehicle is operational. In one example, this may be detected by a key command sensor and/or motion sensor for the vehicle (not shown). If the vehicle is not being operated, the controller 12 may enable a leak detection routine at 303 , described further in FIG. 6 . Leak detection may additionally be regulated by other factors recorded by the controller, such as time elapsed since a last leak detection routine occurred. In alternate embodiments, leak detection methods may be implemented while the vehicle is on, but in an engine-off mode of operation.
[0045] If the controller receives a signal that the vehicle is on, at 304 it is determined if the vehicle is in an engine-on mode or an engine-off mode. If the vehicle is operating in an engine-off mode, the controller may implement the commands shown at 308 . Specifically, the controller may maintain a closed state for each of the FTIV and the CPV. That is, diurnal vapors may be stored in the fuel tank while refueling vapors may are stored in the canister. Additionally, purging routines may be limited for the duration of the engine-off mode of operation. Optionally at 310 , during the engine-off mode of operation, vacuum may be stored in the vacuum accumulator. Specifically, the controller may maintain the VAV closed while vacuum is generated at the venturi coupled to the vacuum accumulator. As previously elaborated, vacuum may be generated due to flow of air and/or exhaust through the venturi irrespective on engine operation mode, such as due to flow of ambient air during vehicle motion or exhaust flow from the brake booster pump.
[0046] If the vehicle is operating in an engine-on mode at 304 , then at 306 , the FTIV and CPV may be maintained in closed positions. At 310 , the controller may maintains the VAV closed while accumulating vacuum due to flow of air and/or exhaust through the coupled venturi. As such, in addition to the vacuum accumulation strategies described above, vacuum may also be generated by coupling the vacuum accumulator to the engine intake manifold. Next, at 314 , purging conditions may be confirmed. Purging conditions may include detection of engine-on operations, a signal from the CPT that the canister pressure is above a predetermined threshold (such as, threshold 2 of FIG. 5 ), and/or a signal from the FTPT that the fuel tank pressure is above a threshold (such as, threshold 3 of FIG. 5 ). If purging conditions are confirmed, a purging routine (further depicted in FIG. 5 ) may be commanded at 315 . If purging conditions are not met, at 318 , the controller may maintain the closed positions of the FTIV and the CPV.
[0047] At 316 , independent of the vehicle operation mode, it may be determined if a fuel tank refueling is requested by the user. If no refueling request is received, the routine may end. In one example, a refueling request may be determined by the controller based on user input through a button, lever, and/or voice command. In response to a refueling request, a refueling routine (further depicted in FIG. 4 ) may be implemented at 320 . However, if the refueling request is received during a purging operation (such as, while purging operations of step 315 are being performed), at 320 , the purging routine may be temporarily disabled for the duration of the refueling event, for example, by temporarily commanding the CPV closed. With this, the routine may end.
[0048] In this way, purging and refueling operations may be better coordinated so as to enable refueling only when fuel tank pressures are within a safe range, while staggering purging operations with refueling so as to reduce excess refueling fuel vapor flow into the engine intake.
[0049] Now turning to FIG. 4 , a refueling routine 400 is shown. At 402 , a user refueling request may be confirmed by the controller. In response to the refueling request, the controller may disable engine operations at 406 . At 408 , purging operations may be disabled, for example, by (temporarily) maintaining the CPV in a closed position. At 410 , the FTIV may be opened and the CVV may be maintained open. Herein, by opening the vapor line between the fuel tank side and the canister side of the fuel vapor circuit, pressure in the fuel tank may be relieved. For example, if a high pressure exists in the fuel tank, air and fuel vapors may flow from the fuel tank through the vapor line and into the canister. In another example, if a vacuum exists in the fuel tank, air may flow from the canister through the vapor line and into the fuel tank. In both examples, pressures of the fuel tank and the canister may go toward equilibrium, such that the fuel tank may be safely and easily opened.
[0050] At 412 , it may be determined whether the absolute value of the fuel tank pressure is below a predetermined threshold (threshold 1 ). If so, at 416 , refueling may be enabled. If the absolute value of the fuel tank pressure is greater than threshold 1 , the controller may delay opening of the refueling door in command 414 , until the fuel tank pressure falls below threshold 1 . The controller may enable refueling by commanding a refueling door to open, for example, by de-energizing a solenoid in the refueling door to enable door opening. The vehicle operator may then have access to the refueling line and fuel may be pumped from an external source into the fuel tank until refueling is determined to be complete at 418 .
[0051] Because the FTIV may remain open during the refueling operation, refueling vapors may flow through the vapor line and into the carbon canister for storage. Until refueling is complete, refueling operations may be maintained at 420 . If refueling is completed at 418 , for example based on input from the fuel level sensor, the refueling door may be closed at 422 , for example by energizing the refueling door solenoid. In response to refueling door closing, at 424 , the FTIV may be closed in thereby ensuring that refueling vapors are stored in the canister side of the fuel vapor circuit. Therein, the refueling routine may be concluded. In this way, refueling may be enabled only when fuel tank pressures are within a safe range, and improving coordination of refueling with purging.
[0052] Now turning to FIG. 5 , a purging routine 500 is depicted. Purging routine 500 may be enabled in response to purging conditions being met (at 314 of FIG. 3 ), such as when the vehicle is operated in an engine-on mode and a refueling event is not requested. At 502 , while the vehicle is operated in the engine-on mode, it may be determined if a canister pressure (Pc), for example as estimated by the CPT, is above a predetermined threshold for purging (threshold 2 ). If the canister pressure is above the threshold, and a refueling request is received at 504 , then at 506 , purging operations may be disabled at least for the duration of refueling, and refueling operations ( FIG. 4 ) may be enabled at 508 . Specifically, CPV may be maintained closed for the duration of the refueling event.
[0053] If the canister pressure is above the threshold, and no refueling request is received at 504 , then at 510 , the controller may command the CPV to open while maintaining the FTIV closed and the CVV open. At 512 , air may flow from the atmosphere into the canister through the vent and a first amount of refueling vapors stored in the canister may be purged to the engine intake manifold. Thus, during the purging of the first amount of fuel vapors from the canister to the intake, no fuel vapors may be purged from the fuel tank to the canister. The first amount of purging may include an amount of fuel vapors (e.g., fuel mass), a duration of purging, and a rate of purging. As such, the CPV may be maintained open until the canister pressure, for example as estimated by the CPT, falls below a threshold (threshold 2 ), at 514 , at which time the CPV may be closed at 516 .
[0054] At 518 , purging conditions of the fuel tank may be determined, for example, based on a fuel tank pressure (such as estimated by the FTPT) being above a threshold for purging (threshold 3 ). If the fuel tank pressure is below threshold 3 , the fuel tank may not require purging and therefore the FTIV may be maintained in a closed position at 520 and the purging routine may end. If the fuel tank pressure is above threshold 3 , the controller may command the FTIV to open at 522 , and at 524 may bleed diurnal vapors, such as a second amount of fuel vapors, from the fuel tank through the vapor line into the canister. The second amount of purging may include an amount of fuel vapors (e.g., fuel mass), a duration of purging, and a rate of purging. The second amount may be based on the first amount purged from the canister. For example, as an amount and duration of purging of the first amount of fuel vapors from the canister increases, the second amount purged from the fuel tank may be increased. During the bleeding of diurnal vapors from the fuel tank, the canister pressure may be monitored and the FTIV may remain open (at 528 ) at least until the canister pressure reaches a threshold. At 526 , it may be confirmed that the canister pressure is above a lower threshold but below an upper threshold (threshold 4 ). If the canister pressure is greater than or equal to threshold 4 , the controller may command the FTIV to close at 530 and the purging routine may be completed.
[0055] In one example, the threshold pressure for purging the fuel tank may be based on the threshold pressure for purging the canister. For example, threshold 4 may be determined as a function of threshold 2 and may be less than threshold 2 to ensure that a first amount of fuel vapors, purged from the canister to the engine, is greater than a second amount of fuel vapors, bled from the fuel tank to the canister. This method of operation may curb pressure fluctuations in the fuel tank by relieving some pressure during purging operations, while limiting the amount and rate of fuel vapor flow to the engine intake manifold. Additionally, this method may change the pressure vs. temperature curve of the fuel tank during cool downs due to removal of fuel mass, affecting subsequent leak detection subroutines (described below) and diurnal vapor generation.
[0056] In this way, by limiting the amount and rate of fuel vapors that flow to the engine during purging, engine flooding may be prevented and variability in vehicle operation experienced by the vehicle operator may be reduced. In alternate embodiments, both fuel tank pressure and canister pressures may be monitored throughout the purging routine. Additionally, the FTIV may be opened concurrently with the CPV. In still other embodiments, the same threshold may be used for commanding both fuel tank purging and canister purging.
[0057] In one example, the vehicle may be a hybrid vehicle with an engine that is selectively operated in response to a battery state of charge. Thus, in one example, the vehicle may be operated with the engine-on, for example, due to the state of charge of the vehicle battery being below a threshold. During vehicle motion, a venturi coupled to the underside of the vehicle body may be configured to generate vacuum due to the flow of air there-through. The generated vacuum may be stored in a vacuum accumulator coupled to the venturi. Similarly, during vehicle operation, vacuum may be generated and stored in the venturi during brake application. For example, the venturi may be coupled to the outlet of a brake booster pump such that exhaust flow the brake booster pump may be flown through the venturi and advantageously used to generate a vacuum. The stored vacuum may be used at a later time, for example, during leak detection operations.
[0058] During the vehicle operation, a controller may keep the FTIV closed and the CPV closed to retain refueling fuel vapors in the canister and diurnal fuel vapors in the fuel tank. When purging conditions are met, for example, when a canister pressure exceeds a threshold due to storage of fuel vapors therein, the controller may open the CPV while keeping the FTIV closed, to thereby purge an amount of fuel vapors to the engine intake. After purging fuel vapors from the canister, that is, when the canister pressure has dropped below a threshold, the controller may then proceed to purge fuel vapors from the fuel tank to the canister and/or engine intake. In one example, the controller may determine whether to purge the diurnal fuel vapors from the fuel tank to the canister and/the intake based on engine operating conditions, and/or a fuel tank pressure. For example, when the fuel tank pressure at the time of purging is above a threshold, the controller may determine that a larger amount of fuel vapors are to be purged from the fuel tank, and may accordingly open the FTIV while keeping the CPV open to thereby purge fuel vapors to the canister and further on to the engine intake. In another example, when the fuel tank pressure at the time of purging is below the threshold, the controller may determine that a smaller amount of fuel vapors are to be purged from the fuel tank, and may accordingly open the FTIV while closing the CPV to thereby purge fuel vapors to the canister and not to the engine intake. Once purging operations are completed, the controller may re-seal the fuel tank and canister by closing the FTIV and CPV to resume storing fuel vapors in the canister and retaining diurnal vapors in the fuel tank. In this way, purging of fuel vapors from the canister and the fuel tank may be coordinated.
[0059] In another example, during vehicle operation (that is, during an engine-on or engine-off mode), a refueling request may be received, such as due to a fuel level in the fuel tank falling below a threshold. As such, if the refueling request is received during a purging operation, the purging may be delayed for at least the duration of the refueling, to advantageously coordinate refueling operations with purging operations. To enable refueling, the engine controller may first turn the engine off, if it was previously turned on. A refueling door may be opened to enable a fuel pump nozzle to be inserted to receive fuel in the fuel tank. However, before opening a refueling valve coupled to the door, to ensure operator safety during refueling, the controller may verify that the fuel tank pressure is below a threshold. If the fuel tank pressure is above the threshold, the controller may open the FTIV to release the retained diurnals into the canister and delay opening of the fuel valve and refueling of the fuel tank until the fuel tank pressure falls below a threshold. In this way, safety during refueling operations may be enhanced.
[0060] If the vehicle is not running, then the controller may be configured to perform one or more leak detection routines for identifying the presence of leaks in the fuel vapor recovery system. Specifically, leaks may be identified by applying a vacuum and monitoring changes in fuel vapor recovery system pressure (such as fuel tank pressure and canister pressure). The vacuum applied for leak detection may be an engine-off natural vacuum created due to a previous engine operation, or may be applied by providing vacuum from the vacuum accumulator. In one example, where the leak is due to a degradation of a fuel vapor recovery system valve, such as the FTIV and/or the CPV, the controller may determine valve degradation by comparing changes in the fuel tank pressure and/or the canister pressure before and after the vacuum application.
[0061] To meet regulatory standards for fuel vapor recovery systems, the hybrid vehicle may include one or more leak detection subroutines. In one example, during a first condition, wherein the hybrid vehicle has been operated in the engine-on mode for an extended duration the vehicle temperature may be high, generating a high pressure in the fuel tank, greater than a predetermine threshold, such as threshold 5 of FIG. 6 , which is sufficient for leak detection. In the first condition, in another example, the fuel tank pressure to be negative (a vacuum) as fuel stored in the fuel tank may have been consumed by the engine, such that the absolute value of the fuel tank pressure is greater than a predetermined threshold (such as threshold 5 of FIG. 6 ), and is sufficient for leak detection.
[0062] If a high pressure or vacuum is present in the fuel tank (greater than a threshold), the fuel tank pressurization may be advantageously used to test for leaks in the system and identify degradation of the fuel vapor recovery system components, such as the FTIV, the CPV, and/or the CVV, in a primary leak detection subroutine. For example, with the fuel tank sealed (by closing the FTIV and CPV) and pressurized, a rate of change or pressure in the sealed fuel tank may be monitored. As such, in the absence of leaks, the fuel tank pressure may be substantially constant, and may not fluctuate. Thus, in one example, the controller may determine degradation of one or more of the FTIV, the refueling valve, and/or the FTPT in a response to a rate of change of the fuel tank being greater than a threshold (such as threshold 6 of FIG. 6 ) due to one or more leaks in the valves of the fuel tank or malfunction of the fuel tank pressure sensor. If the pressure of the fuel tank did not substantially change, the FTIV may be commanded open such that air/fuel vapors are permitted to move through the vapor line, and the fuel tank pressure may be monitored again. As such, upon opening the FTIV, in the absence of leaks, the fuel tank pressure may be expected to decreases over time, for example decrease with a rate of change of fuel tank pressure greater than a threshold (such as threshold 7 of FIG. 6 ), due to the flow of vapors through the vapor line, If the rate of change of the fuel tank pressure is less than the threshold, the controller may determine that the FTIV is stuck in a closed position, and thus the FTIV is degraded.
[0063] As such, if the FTIV is functional, the canister pressure and the fuel tank pressure can be expected to generally reach equilibrium. For example, the fuel tank pressure may gradually decrease towards the canister pressure, while the canister pressure may gradually increase towards the fuel tank pressure. Thus in another example, the controller may determine degradation in one or more of the CPV, the CVV, and/or the CPT based on the rate of change of the canister pressure being greater than a threshold (threshold 10 ) after a predetermined duration of time has elapsed. Upon indication of degradation of any of the above mentioned fuel vapor recovery system components, the controller may set a diagnostic code.
[0064] Optionally, in another example, the controller may generate the first condition, such that a vacuum or pressure sufficient for leak detection is generated in the fuel tank. In one example, this may be accomplished by allowing the engine to run after the vehicle has stopped to generate vacuum in the fuel tank through fuel consumption, or pressure by increased vehicle temperature. In another example, the controller may delay emission leak check for a predetermined duration and monitor temperature change during the duration of the delay, until temperature change is greater than a predetermined threshold (such as threshold 8 of FIG. 7 ). The controller may then monitor fuel tank pressure and if corresponding change in pressure has not occurred with the change in temperature, degradation of one or more of the FTIV, the refueling valve, and/or the FTPT is determined by the controller. Each of these examples may allow for the primary leak detection subroutine to be implemented by the controller, as described above.
[0065] In yet another example, during a second condition, wherein the hybrid vehicle has been operated in the engine-off mode for an extended duration, the vehicle temperature may be close to ambient temperature and fuel consumption may be low. In this example, neither of a high pressure nor a vacuum are generated in the fuel tank and the fuel tank pressure may be less than a predetermine threshold (such as threshold 5 of FIG. 6 ), and is insufficient for leak detection.
[0066] If a high pressure or vacuum is not present in the fuel tank (less than a threshold), an external vacuum source, such as a vacuum accumulator, may be advantageously used to test for leaks in the system and identify degradation of the fuel vapor recovery system components, such as the FTIV, the CPV, and/or the CVV, in a secondary leak detection subroutine. The vacuum accumulator may obtain negative pressure/vacuum by one or more methods. For example, the vacuum accumulator may be coupled to the engine intake manifold such that negative pressure is stored while the vehicle is operated in the engine-on mode. As such, the presence of a vacuum may be dependent on engine-on operation time. Optionally, the controller may command the engine to run after the vehicle is shut off to increase engine-on time and increase the amount of vacuum stored in the vacuum accumulator. In another example, vacuum accumulation may be independent of engine-on time. As such, the vacuum accumulator may be coupled to a venturi located at a position on or within the vehicle that receives air flow, such as on the underside of the vehicle, or in the exhaust pathway of a brake booster pump. It may be appreciated that one or more of the above methods may be used to accumulate vacuum for use in the secondary leak detection subroutine.
[0067] As such, in the secondary leak detection subroutine, with the canister sealed (by closing the FTIV, CVV and CPV) and pressurized by applying a vacuum from the vacuum accumulator via opening of the VAV, a rate of change or pressure in the sealed canister may be monitored. Thereby in the absence of leaks, for example, the canister pressure may be substantially constant, and may not fluctuate. Thus, in one example, the controller may determine degradation of one or more of the FTIV, the CVV, the CPV, and/or the CPT in a response to a rate of change of the fuel tank being greater than a threshold (such as threshold 10 of FIG. 8 ) due to one or more leaks in the valves of the canister or malfunction of the canister pressure sensor. If the pressure of the canister did not substantially change, the FTIV may be commanded open such that air/fuel vapors are permitted to move through the vapor line, and the canister pressure may be monitored again. As such, upon opening the FTIV, in the absence of leaks, the canister pressure may be expected to increase over time, for example increase with a rate of change of canister pressure greater than a threshold (such as threshold 10 of FIG. 8 ), due to the flow of vapors through the vapor line. If the rate of change of the canister pressure is less than the threshold, the controller may determine that the FTIV is stuck in a closed position, and thus the FTIV is degraded.
[0068] As such, if the FTIV is functional, the canister pressure and the fuel tank pressure can be expected to generally reach equilibrium. For example, the fuel tank pressure may gradually decrease towards the canister pressure, while the canister pressure may gradually increase towards the fuel tank pressure. Thus in another example, the controller may determine degradation in one or more of the refueling vavle and/or the FTPT based on the rate of change of the fuel tank pressure being greater than a threshold (threshold 6 ) after a predetermined duration of time has elapsed. Upon indication of degradation of any of the above mentioned fuel vapor recovery system components, the controller may set a diagnostic code.
[0069] As discussed above, during leak detection, an order of detecting leaks in the components of the fuel vapor recovery system may be adjusted based on the availability of sufficient pressure and/or vacuum in the fuel tank (such as, an engine-off natural vacuum) or an amount of vacuum that may be supplied by the vacuum accumulator. Herein, two example leak detection routines are depicted in FIGS. 6-8 . A primary leak detection routine 600 may use pressure or vacuum from the fuel tank to detect leaks in a first order of detection including first determining the presence of leaks in the fuel tank and then applying the pressure/vacuum from the fuel tank to the canister to determine the presence of leaks in the canister. A secondary leak detection subroutine 800 may detect leaks in a second, alternate, order of detection including using vacuum from an external source (such as the accumulator) applied to the canister to first determine the presence of leaks in the canister and then applying the vacuum to the fuel tank to determine the presence of leaks in the fuel tank. Various sources and methods may be used to apply a vacuum or pressure to the canister and/or the fuel tank, as elaborated in FIG. 8 . Maps of example pressure and temperature signals that may be received by the controller during the leak detection routines of FIGS. 6-8 are shown in FIGS. 9-12 .
[0070] Returning to FIG. 6 , it shows a primary leak detection routine 600 . Starting at 602 , the controller may first estimate a fuel tank pressure (for example, based on a signal received from the FTPT) and determine if there is sufficient pressure or vacuum in the fuel tank to perform leak detection. In one example, sufficient pressure or vacuum may be determined based on an absolute value of the fuel tank pressure being greater than a predetermined threshold (threshold 5 ). Herein, the absolute fuel tank pressure may refer to an amount of positive pressure in the fuel tank, when the leak detection is performed by applying positive pressure, or may refer to an amount of vacuum in the fuel tank, when the leak detection is performed by applying a vacuum (that is, negative pressure).
[0071] Map 1000 in FIG. 10 depicts example ranges of acceptable absolute fuel tank pressures and thresholds for leak detection based on whether the leak detection includes applying a positive pressure or a vacuum. Herein, threhold 5 extends equally in both directions of vacuum and positive pressure application (as shown by dotted-lines) on each side of the x-axis, depicted as range 1010 . In alternate embodiments, different thresholds may be applied depending on whether a positive pressure or a vacuum is applied during leak detection.
[0072] Each of the curves 1002 , 1004 , 1006 , and 1008 represent example fuel tank pressures. In the present embodiment, the absolute fuel tank pressure signal may be monitored and not a rate of change of fuel tank pressure. The controller may take detect the absolute pressure signal at various points in time, such as t 0 , t 1 , t 2 , t 3 , t 4 , or t n . Based on the absolute fuel tank pressure determined at a time when leak detection is requested, the controller may determine whether to perform the primary leak detection routine, including detecting leaks in the fuel tank before detecting leaks in the canister, or whether to perform the secondary leak detection routine, including detecting leaks in the fuel tank after detecting leaks in the canister. In this example, a signal detected at t n is further described, wherein t n is the time at which the controller receives an indication for leak detection may be enabled, such as shutting off of the vehicle and/or time elapsed since last leak detection event.
[0073] In one example, at 602 , the absolute fuel tank pressure estimated at t n may be a positive pressure that is less than threshold 5 (as shown in curve 1004 ) or a vacuum that is greater than threshold 5 (as shown in curve 1006 ). In response to insufficient absolute pressure in the fuel tank estimated at 602 , the primary leak detection routine 600 may be disabled by the controller at 603 , and vacuum may be applied from one or more alternative pressure and vacuum sources by enabling vacuum application routine 700 (shown in FIG. 7 ). If sufficient, vacuum is generated in the fuel tank in routine 700 , 603 may loop back to the start of the primary leak detection routine 600 , starting at 602 . Alternatively, at 605 , a secondary leak detection routine with an alternate order of leak detection (as elaborated in FIG. 8 ), may be enabled. In comparison, if the absolute fuel tank pressure estimated at 602 is a positive pressure that is greater than threshold 5 (as shown in curve 1002 ) or a vacuum that is less than threshold 5 (as shown in curve 1008 ), then in response to sufficient absolute pressure in the fuel tank, the primary leak detection routine may continued.
[0074] Returning to FIG. 6 , if sufficient pressure/vacuum is detected in the fuel tank, at 604 , the fuel tank pressure may be monitored over time. That is, a change in fuel tank pressure over time (or a rate of change of fuel tank pressure) may be monitored. At 606 , it may be determined whether the change in fuel tank pressure over time is less than a threshold (threshold 6 ). As such, since the fuel tank remains sealed during leak detection, a change in fuel tank pressure over time may be indicative of a leak at the fuel tank isolation valve (due to FTIV degradation) and/or degradation of the FTPT. Thus, if the change in fuel tank pressure over time is more than the threshold, at 608 FTIV degradation may be determined and at 626 , a diagnostic code may be set. If the change in fuel tank pressure over time is less than the threshold, then at 610 , the controller may determine that no leaks are present, and that the valves are not degraded.
[0075] Examples of changes in fuel tank pressure over time are shown in map 900 of FIG. 9 . Herein, the controller monitors changes in fuel tank pressure (by receiving signals from the FTPT) beginning at t 0 and continuing for a predetermined duration, herein to t n . Line 904 depicts a fuel tank positive pressure that decreases over time and line 906 depicts a fuel tank vacuum that increases over time. In this example, each of lines 904 and 906 indicate the presence of leaks due to a change in fuel tank pressure over time that is greater than a threshold. In comparison, line 902 shows a fuel tank positive pressure and line 908 shows a fuel tank vacuum that change over time at a rate lower than the threshold. Herein, each of lines 902 and 908 may indicate that there are no leaks in the system and that the valves of the fuel vapor recovery system are not degraded.
[0076] Returning to FIG. 6 , after it is determined that no leaks are present in the fuel tank and the FTPT is operative, the controller may close the CVV and open the FTIV at 612 , thereby sealing the canister from the atmosphere and applying the pressure or vacuum from the fuel tank to the canister by allowing flow of air and fuel vapors through the vapor line. The CPV may be maintained in a closed position, as no purging operations may occur when the vehicle is off (see FIG. 3 ). At 614 , a change in absolute fuel tank pressure over time may again be monitored by the controller by receiving signals from the FTPT, and it may be determined if the rate of change of absolute fuel tank pressure is greater than a threshold (threhsold 7 ). Herein, in the absence of leaks, after opening the FTIV, the flow of fuel vapors from the fuel tank to the canister may be expected to cause the fuel tank pressure to change. Thus, if the change in fuel tank pressure over time is below the threshold, then at 616 , the controller may determine that a leak is present, and that the FTIV is degraded (e.g. is inoperative) and may set a diagnostic code at 626 . However, if the change in fuel tank pressure over time is greater than threshold, then at 618 the controller may determine that the FTIV is not degraded.
[0077] At 620 , the controller may then monitor the canister pressure over time through signals from the CPT beginning at t 0 and continuing for a predetermined duration (such as, to t n ), and a rate of canister pressure change is determined at 622 . For example, it may be determined if the canister is able to hold pressure or vacuum over time after the fuel tank and the canister have equalized. At 628 , the controller may determine that there is no leak in the canister based on a rate of change in canister pressure over time being less than a threshold (threshold 10 ). In one example, no leaks may be determined in the system as the change in canister pressure is less than thershold 10 , such as sample pressures line 902 and line 908 of FIG. 9 . In comparison, at 624 , leaks may be determined in response to the change in canister pressure over time being greater than a threshold 10 , such as sample pressure readings line 904 and line 906 of FIG. 9 . The controller may determine the presence of a leak in the canister, degradation of a canister purge valve, or CPT degradation, and set a diagnostic code at 626 .
[0078] If at 602 the absolute value of fuel tank pressure is less than threshold 5 , such as sample pressure readings line 1004 and line 1006 of FIG. 10 , then one or more alternate pressure/vacuum generation routines may be implemented by the controller, as now explained with reference to FIG. 7 . One or more of the various vacuum generating strategies described herein may be either operated at different times, or concurrently. In one example, when the first vacuum generating strategy is performed and a fuel tank temperature is measured, the second and third strategies may be disabled. In another example, when engine operation is continued in the second strategy, engine vacuum may be stored in the accumulator and applied for leak detection, as in the third strategy. However, in alternate embodiments, only one of the engine vacuum (directly from the engine) or vacuum from the accumulator may be enabled for leak detection. That is, when engine operation is continued in the second strategy, the vacuum accumulator may be closed and the third strategy may be disabled.
[0079] In a first strategy, at 704 , leak detection may be delayed and a fuel tank temperature, such as from a fuel tank temperature sensor, may be recorded at t 0 . After a predetermined duration of time, t n , has elapsed, the fuel tank temperature may again be recorded and the controller may determine if the temperature has heated or cooled sufficiently to generate a pressure change in the fuel tank. This is represented in 710 as the absolute value of the change in temperature between t 0 and t n being greater than a threshold (threshold 8 ). In one example, threshold 8 may be related to threshold 5 , such that the temperature change corresponds to an amount of pressure/vacuum that is sufficient for leak detection.
[0080] Example fuel tank temperature readings, as received from fuel tank temperature sensor, are shown in map 1200 of FIG. 12 . Herein line 1202 demonstrates a change from a relatively higher temperature to a relatively cooler temperature, thereby decreasing a pressure in the fuel tank; while line 1206 demonstrates a relatively cooler temperature changing to a relatively warmer temperature, thereby increasing a pressure in the fuel tank. Each of lines 1202 and 1206 show a temperature change greater than the threshold, thereby indicating to the controller that a corresponding, sufficient amount of pressure change, has occurred. In comparison, line 1204 , which is generally flat, represents a temperature change that is less than the threshold, thereby indicating that a sufficient pressure change has not occurred.
[0081] Returning to FIG. 7 , if the change in temperature (and thus a corresponding change in pressure) at 710 is not greater than the threshold, the routine may return to 704 and continue to delay the leak. However, if the temperature change is greater than the threshold, at 712 (as in 602 ), the controller may then determine if the absolute value of the fuel tank pressure is greater than a threshold (threshold 5 ). In one example, at 716 , when the absolute fuel tank pressure remains below threshold 5 , in response to no pressure change in conjunction with a temperature change, the controller may determine that leaks are present in the system. For example, it may be determined that leaks are present in the FTIV, or CPV, or that the FTPT is degraded. Accordingly, at 718 , a diagnostic code may be set. If the absolute pressure of the fuel tank is greater than threshold 5 at 712 , then at 813 , the primary leak detection routine ( FIG. 6 ) may be resumed.
[0082] In a second vacuum generating strategy, beginning at 724 , the controller may close the CVV and maintain the closed position of the CPV and FTIV, such that the canister side of the circuit is sealed. Vacuum from a vacuum accumulator is then applied to the canister by opening the VAV at 726 . The vacuum accumulator may acquire vacuum from one or more of the engine intake, an ambient air stream, or the brake booster exhaust pathway. At 728 , the controller may determine if the canister pressure is less than a threshold, threhsold 9 , by receiving a signal from the CPT. In one example at 729 , wherein the canister pressure is less than threshold 9 , a secondary leak detection routine ( FIG. 8 ) may be enabled. If the canister pressure is greater than a threshold 9 upon application of a vacuum, at 730 , the controller may determine that one or more of the canister valves, or FTIV, or CPT are degraded.
[0083] Example changes in canister pressure, as received from the CPT, are shown in map 1100 of FIG. 11 . Herein, the dotted-line represents threshold 9 . In the present embodiment, the canister pressure is detected at various points in time, such as t 0 , t 1 , t 2 , t 3 , t 4 , or t n . For this example, a signal detected at t n is further described, wherein t n is the time at which other signals are received by the controller indicating that leak detection may be enabled, such as time elapsed since opening of the VAV.
[0084] At t n , example CPT reading shown in line 1102 may be a positive pressure that is greater than threshold 9 and example CPT reading shown in line 1104 may be a vacuum that is greater than threshold 9 . If at the time that a vacuum is applied on the canister, the canister pressure is greater than the threshold, as shown in line 1102 and line 1104 , the secondary leak detection routine 800 ( FIG. 8 ) may be disabled by the controller and a diagnostic code may be set to report degradation of one or more the canister valves and/or the CPT. In comparison, if at t n , the canister pressure shows that a canister vacuum is less than threshold 9 , as shown in line 1106 , the secondary leak detection routine 800 ( FIG. 8 ) may be enabled by the controller.
[0085] Returning to FIG. 7 , in a third vacuum generating strategy, beginning at 720 , the engine may be run for a duration (such as a short duration) after the vehicle is shut off. The duration of the continued engine operation may correspond to a length of time required to generate sufficient pressure/vacuum, for example, a duration required to bring the absolute pressure in the fuel tank above a threshold (such as threshold 5 ). If the engine is run after the vehicle is shut off and absolute fuel tank pressure is less than threshold 5 (at 712 ), then at 716 , the controller may determine that a leak is present in the fuel tank (e.g., due to FTIV degradation) and may set a diagnostic code at 718 . If the absolute value of fuel tank pressure is greater than threshold 5 at 712 , the controller may initiate primary leak detection routine 600 .
[0086] Optionally, alternative to generating a vacuum in the fuel tank, the continued engine operation at 720 may be used to store vacuum in a vacuum accumulator, as in 722 . In this case, the vacuum accumulator may be coupled to the engine intake and vacuum may be applied to the canister by opening of the VAV, as in 726 . The routine may then return to the second vacuum generating strategy (as previously elaborated at 728 - 730 ). If sufficient vacuum is present in the canister (that is, canister pressure is less than threshold 9 ), then at 729 , the secondary leak detection routine 800 may be implemented by the controller, as shown in FIG. 8 .
[0087] Now turning to FIG. 8 , a secondary leak detection routine is depicted that may be enabled in response to insufficient fuel tank pressure or vacuum for performing the primary leak detection routine. In the secondary routine, the canister may be checked for leaks before confirming operation of the FTIV, and detecting leaks in the fuel tank. Specifically, a vacuum may be applied from a source other than engine-off natural vacuum, such as the vacuum generated in FIG. 7 , and leak detection may be enabled in the canister before detecting leaks in the fuel tank.
[0088] At 802 , a vacuum is applied to the canister from a vacuum accumulator such that the canister pressure is less than threshold 9 (as previously shown at 726 and 728 of FIG. 7 ). Once sufficient vacuum has been detected in the canister, at 804 , canister pressure is monitored over time. At 806 , it may be confirmed whether the change in canister pressure over time is less than a threshold (threshold 10 ). As the canister may remain sealed during leak detection, a change in canister pressure over time being greater than a threshold at 806 may be indicative of a leak, for example, at one more of the canister valves and/or degradation of the CPT (at 808 ), and a diagnostic code may be set by the controller at 826 . A sample pressure reading indicating a leak may be represented by line 906 of FIG. 9 . If the change in canister pressure over time is less than the threshold at 806 , then at 810 , the controller may determine that the valves of the canister have no leaks and the CPT is operative. A sample pressure reading indicating that no leak is present may be represented by line 908 of FIG. 9 .
[0089] After it is determined that no leaks are present in the canister and the CPT is operative, the controller may open the FTIV at 812 , thereby applying the vacuum from the canister to the fuel tank by allowing flow of air and fuel vapors through the vapor line. The CPV may be maintained in a closed position, as no purging operations may occur when the vehicle is off (see FIG. 3 ). At 814 , a change in canister pressure over time may again be monitored by the controller. If the change in canister pressure over time is less than a threshold, the controller may determine that the FTIV is inoperative (e.g., is stuck closed) at 816 , and may set a diagnostic code at 826 . However, if a change in canister pressure over time is greater than the threshold 10 , then at 818 , the controller may determine that the FTIV is operative (e.g., is not stuck open), as in 818 . In this case, line 908 of FIG. 9 may show no change over time and may indicate malfunction of the FTIV, while line 906 may show change in pressure over time and may indicate that the FTIV is operative.
[0090] At 820 , the controller may monitor the fuel tank pressure over time, for example, through signals from the FTPT, beginning at t o and continuing for a predetermined duration to t n . The change in fuel tank pressure over time may be determined to be greater or less than a threshold (threshold 6 ) at 822 . At 828 , it may be determined by the controller that there is no leak if the change in fuel tank pressure over time is less than threshold 6 . Specifically, a fuel tank pressure reading showing little or no change over time indicates that there are no leaks present in the fuel tank, such as line 908 of FIG. 9 . In comparison, a fuel tank pressure reading showing change over time indicates that there may be a leak present in the fuel tank, such as line 906 of FIG. 9 . Accordingly, the controller may determine the presence of leaks at 824 and set a diagnostic code at 826 , respectively. After diagnostic codes indicating leaks are set by the controller, secondary leak detection subroutine 800 may be ended.
[0091] In this way, leak detection routines may be adjusted based on the availability of sufficient amount of pressure or vacuum for the leak detection. Further, purging operations may be coordinated with refueling operations and leak detection operations, thereby improving fuel vapor management, particularly in hybrid vehicles.
[0092] It will further be appreciated that the configurations and routines disclosed herein are exemplary in nature, and that these specific embodiments are not to be considered in a limiting sense, because numerous variations are possible. For example, the above diagnostic routines may be decoupled such that leak detection of the fuel tank and the canister are performed as distinct operations. The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of the various systems and configurations, and other features, functions, and/or properties disclosed herein.
[0093] The following claims particularly point out certain combinations and sub-combinations regarded as novel and non-obvious. These claims may refer to “an” element or “a first” element or the equivalent thereof. Such claims should be understood to include incorporation of one or more such elements, neither requiring nor excluding two or more such elements. Other combinations and sub-combinations of the disclosed features, functions, elements, and/or properties may be claimed through amendment of the present claims or through presentation of new claims in this or a related application. Such claims, whether broader, narrower, equal, or different in scope to the original claims, also are regarded as included within the subject matter of the present disclosure. | A method and system for fuel vapor control in a hybrid vehicle (HEV). The HEV fuel vapor recovery system includes a fuel tank isolation valve, which is normally closed to isolate storage of refueling from storage of diurnal vapors. The method for fuel vapor control includes selectively actuating the fuel tank isolation valve during interrelated routines for refueling, fuel vapor purging, and emission system leak detection diagnostics to improve regulation of pressure and vacuum the HEV fuel vapor recovery system. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a completion application of co-pending U.S. Provisional Application Ser. No. 60/800,350 filed May 15, 2006 for “Cement Composition” the entire disclosure of which is hereby incorporated by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention pertains to cementitious products. More particularly, the present invention pertains to cementitious products having heat generating components incorporated therewith. Even more particularly, the present invention pertains to a cementitious product having heat absorbing materials incorporated therewith or incorporated into a topcoat overlying the cementitious product.
[0004] 2. Description of the Prior Art
[0005] As is known to those skilled in the art to which the present invention pertains the ability to melt snow and ice from cement and other road materials is an important process in those regions where there are below-freezing temperatures. Typically, the Northeast, Midwest and Northwest portions of the United States as well as parts of Northern Europe, Asia and Australia during their winters, suffer from these conditions. Usually, snow removal invokes the use of plows, as well as salt, to remove snow and melt ice. However, salt, in and of itself, tends to pit and/or otherwise erode the surface be it tarmac, asphalt, cement and the like. Similarly, plows have a tendency to cut or otherwise disrupt the surface due to the cutting of the surface with the blade of the plow.
[0006] The present invention, as hereinafter described, provides a material which absorbs heat and is used to facilitate the melting of the precipitate, be it snow or ice, on the surface of the road.
SUMMARY OF THE INVENTION
[0007] It has been found that by incorporating a mixture of powdered zinc and sulphur either directly into a roadway material and, preferably, cement or concrete or as a topcoat applied thereover, improved melting of ice and/or improved heat absorption of a roadway is accomplished.
[0008] In using the two powders, generally, the two powders are present in a respective weight ratio of sulphur to zinc of about 3:1 to about 1:3 and preferably from about 1:1 to about 2:1 whether incorporated into the cement or concrete or other roadway composition or the topcoat.
[0009] The topcoat, where used, is preferably, an aqueous latex having the powders admixed therewith.
[0010] For a more complete understanding of the present invention reference is made to the following detailed description, and illustrative example.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0011] As noted hereinabove, the present invention contemplates the inclusion of a mixture of powdered sulphur and zinc to improve the heat absorption thereof.
[0012] In a first embodiment hereof an improved cement or concrete or other roadway material is provided by incorporating therewith the powder mixture and in a second embodiment hereof, the powder mixture is incorporated into a topcoat for the roadway and is applied thereover.
[0013] Turning to the first embodiment hereof, it is contemplated that the powders be incorporated into a cementitious composition. In using the powders to prepare such a cementitious composition, the sulphur will be present in an amount ranging from about 0.5 to about 2.0 parts, by weight thereof, per hundred parts by weight of the total composition. The zinc powder will be present in an amount ranging from about 0.05 to about 2.0 parts, by weight, per hundred parts, by weight, of the total cement composition.
[0014] In forming a cement or concrete composition in accordance herewith, generally, the composition will contain about 10 to 35 parts, by weight, of Portland cement, per hundred parts, by weight, of the total composition.
[0015] The cement composition will also include from about 70 to about 85 parts of limestone (CaCO 3 ) or gravel, such as 60-40 gravel, and the like as well as mixtures thereof, also from about two parts to about 10 parts of water, by weight, per hundred parts, by weight, of the total composition.
[0016] Although not wishing to be bound by any theory it appears that the minor amount of sulphur warms up the surface of the cement as tires traverse the surface and the zinc powder acts as a heat conductor.
[0017] In accordance with the second aspect or embodiment hereof, the powder mixture is incorporated into an aqueous latex topcoat. Such topcoats are well-known and commercially available and, generally, comprise water and a dispersion of polymeric material. When the water evaporates the polymer particles coalesce to form a solid film. With the powders in the latex, they become suspended in the aqueous dispersion and remain as part of the film upon evaporation of the water.
[0018] When the powder mixture is used in such a topcoat, the powders will be present, preferably, in about a 3:1 to 1:3 weight ratio of sulphur to zinc in the latex composition. Ordinarily, each of the sulphur and zinc powders will be present in an amount ranging from about 10% to about 20%, by weight, based upon the total weight of the composition.
[0019] When the powder mixture is used in the topcoat, the two powders are mixed together or, are added separately, into the aqueous latex at room temperature and with sufficient stirring or agitation to suspend the powders therein. To avoid precipitation of the powders, preferably, the powders are incorporated into the latex at the time of deployment or just prior thereto. The powder-containing latex is then applied by any suitable means such as by spraying, brushing, or the like to form a topcoat over the road surface. Optimally, this is done at ambient conditions.
[0020] As noted, the powders do not dissipate on the surface, but rather remain dispersed in the polymer coalescence after evaporation of the water.
[0021] The present invention, further, contemplates the incorporation of the powders in both the topcoat and the cement composition.
[0022] In practicing the present invention, the zinc powder will have a particle size of about 10 microns and the sulfur will have a mesh size of about 100 mesh.
[0023] From the above, it is seen that there has been described a cement composition or topcoat which promotes heat retention therewithin.
[0024] Following is an illustrative, non-limiting example of the present invention. In the example all parts are by weight absent indications to the contrary.
EXAMPLE
[0025] This example illustrates the use of the present invention as a cement composition.
[0026] A series of cement slabs were prepared during a Fall month by entraining in dry air 388 parts of 60-40 gravel, 70 parts of Portland Cement, 11.1 parts of sulphur, 4.0 parts of zinc, and 33 parts of water and thoroughly mixing the ingredients together to provide a uniform composition.
[0027] After first preparing the mixture, two 3×3×4 inch slabs were prepared from this mixture by pouring the so-produced cement into a suitable mold.
[0028] Two additional slabs were prepared using the same composition, except that the zinc and sulphur powders were eliminated from the mixture thereto.
[0029] Each of the four slabs was allowed to set for seven days in the outdoors during the Fall month where there was an average temperature of about 45° F. After seven days in the outdoors, the surface heat of each slab was measured using a conventional temperature gun. The surface of the slabs having the powder mixture incorporated therewith evidenced a 20° F. temperature differential between the slabs containing the powder mixture and the slabs without.
[0030] In addition, after observing the slabs in the ambient, each of the four slabs were exposed to heat using a 250 watt heat lamp which was directly focused onto each slab for a period of 5 minutes while the temperature in the outdoors was about 40° F. The temperature of the surface of each slab was then measured using a Temperature gun. The surface of the slabs having the zinc and sulphur admixture within the cement showed a temperature of about 75° F., whereas the slabs without the zinc and sulphur mixture only measured about 49° F.
[0031] From the above, it is seen that with the zinc and sulphur admixture heat retention is greatly increased. | A powder mixture for improving heat retention in cementitious or similar roadway compositions or a topcoat therefor. This powder mixture is a zinc and sulphur powder mixture. The mixture is added either directly into the roadway composition or is applied as a component of a water-based latex topcoat. The two powders improve the heat retention capability of the roadway composition. | 2 |
CROSS REFERENCE RELATED APPLICATIONS
This application is a continuation of U.S. Ser. No. 08/607,903, filed Feb. 27, 1996, to issue as U.S. Pat. No. 5,876,453, which was filed as PCT/US95/15576 filed on Nov. 30, 1995, which is CIP U.S. patent application Ser. No. 08/351,214, filed Nov. 30, 1994, now abandoned.
FIELD OF THE INVENTION
The present invention relates to processes for improving the surfaces of devices to be surgically implanted in living bone, and to implant devices having the improved surfaces.
BACKGROUND OF THE INVENTION
The success of prosthetic devices surgically implanted in living bone depends substantially entirely on achieving and maintaining an enduring bond between the confronting surfaces of the device and the host bone. Surgical procedures for preparing living bone to receive a surgically implanted prosthetic device have been known for twenty years or more, but considerable controversy remains concerning the ideal properties of the surface of the device which confronts the host bone.
It is known through clinical experience extending over several decades that titanium and its dilute alloys have the requisite biocompatability with living bone to be acceptable materials for use in making surgically implantable prosthetic devices, when the site of installation is properly prepared to receive them. There is, however, less certainty about the ideal physical properties of the surfaces of the prosthetic devices which confront the host bone. For example, the endosseous dental implant made of titanium enjoys sufficient predictable success to have become the artificial root most frequently chosen for restoring dentition to edentulous patients, but that success depends in part on the micromorphologic nature of the surface of the implant which comes in contact with the host bone. Because there is no standard for the surface micromorphology of dental implants, the surfaces of commercial implants have a wide range of available textures. It is known that osseointegration of dental implants is dependent, in part, on the attachment and spreading of osteoblast-like cells on the implant surface. It appears that such cells will attach more readily to rough surfaces than to smooth surfaces, but an optimum surface for long-term stability has not yet been defined.
Wilke, H. J. et al. have demonstrated that it is possible to influence the holding power of implants by altering surface structure morphology: “The Influence of Various Titanium Surfaces on the Interface Strength between Implants and Bone”, Advances in Biomaterials, Vol. 9, pp. 309-314, Elsevier Science Publishers BV, Amsterdam, 1990. While showing that increased surface roughness appeared to provide stronger anchoring, these authors comment that it “cannot be inferred exclusively from the roughness of a surface as shown in this experiment. Obviously the shear strength is also dependent on the kind of roughness and local dimensions in the rough surface which can be modified by chemical treatment.”
Buser, D. et al., “Influence of Surface Characteristics on Bone Integration of Titanium Implants”, Journal of Biomedical Materials Research, Vol. 25, pp. 889-902, John Wiley & Sons, Inc., 1991, reports the examination of bone reactions to titanium implants with various surface characteristics to extend the biomechanical results reported by Wilke et al. The authors state that smooth and titanium plasma sprayed (“TPS”) implant surfaces were compared to implant surfaces produced by alternative techniques such as sandblasting, sandblasting combined with acid treatment, and plasma-coating with HA. The evaluation was performed with histomorphometric analyses measuring the extent of the bone-implant interface in cancellous bone. The authors state, “It can be concluded that the extent of bone-implant interface is positively correlated with an increasing roughness of the implant surface.”
Prior processes that have been used in attempts to achieve biocompatible surfaces on surgically implantable prosthetic devices have taken many forms, including acid etching, ion etching, chemical milling, laser etching, and spark erosion, as well as coating, cladding and plating the surface with various materials, for example, bone-compatible apatite materials such as hydroxyapatite or whitlockite or bone-derived materials. Examples of U.S. patents in this area are U.S. Pat. No. 3,855,638 issued to Robert M. Pilliar Dec. 24, 1974 and U.S. Pat. No. 4,818,559 issued to Hama et al. Apr. 4, 1989. A process of ion-beam sputter modification of the surface of biological implants is described by Weigand, A. J. et al. in J. Vac. Soc. Technol., Vol. 14, No. 1, January/February 1977, pp. 326-331.
As Buser et al. point out (Ibid p. 890), the percentage of bone-implant contact necessary to create sufficient anchorage to permit successful implant function as a load-bearing device over time remains unclear. Likewise, Wennerberg et al., “Design and Surface Characteristics of 13 Commercially Available Oral Implant Systems”, Int. J. Oral Maxillofacial Implants 1993, 8:622-633, show that the different implants studied varied considerably in surface topography, and comment: “Which of the surface roughness parameters that will best describe and predict the outcome of an implant is not known” (p. 632).
Radio-frequency glow-discharge treatment, also referred to as plasma-cleaning (“PC”) treatment, is discussed in Swart, K. M. et al., “Short-term Plasma-cleaning Treatments Enhance in vitro Osteoblast Attachment to Titanium”, Journal of Oral Implantology, Vol. XVIII, No. 2 (1992), pp. 130-137. These authors comment that gas plasmas may be used to strip away organic contaminants and thin existing oxides. Their conclusions suggest that short-term PC treatments may produce a relatively contaminant-free, highly wettable surface. U.S. Pat. No. 5,071,351, issued Dec. 10, 1991, and U.S. Pat. No. 5,188,800, issued Feb. 23, 1993, both owned by the assignee of the present application, describe and claim methods and means for PC cleaning of a surgical implant to provide a contact angle of less than 20 degrees.
Copending application Ser. No. 08/149,905, filed Nov. 10, 1993, owned by the assignee of the present application, describes and claims inventions for improving the surfaces of surgically implantable devices which employ, among other features, impacting the surface with particles of the same material as the device to form the surface into a desired pattern of roughness.
SUMMARY OF THE INVENTION
It is a primary object of the present invention to produce an implant surface having a roughness that is substantially uniform over the area of the implant that is intended to bond to the bone in which the implant is placed.
It is a further object of this invention to provide an improved surgically implantable device having on its surface a substantially uniform micromorphology.
It is another object of the invention to provide a process or processes for manufacturing such improved implant devices.
It is an additional object of the invention to provide such improved implant devices which can be manufactured without contaminating the surfaces thereof.
It is a more specific object of the invention to provide an improved etch-solution process that will result in a substantially uniform surface topography on surgically implantable devices.
In accordance with the present invention, the foregoing objectives are realized by removing the native oxide layer from the surface of a titanium implant to provide a surface that can be further treated to produce a substantially uniform surface texture or roughness, and then performing a further, and different, treatment of the resulting surface substantially in the absence of unreacted oxygen. The removal of the native oxide layer may be effected by any desired technique, but is preferably effected by immersing the implant in hydrofluoric acid under conditions which remove the native oxide quickly while maintaining a substantially uniform surface on the implant. The further treatment is different from the treatment used to remove the native oxide layer and produces a desired uniform surface texture, preferably acid etching the surface remaining after removal of the native oxide layer. To enhance the bonding of the implant to the bone in which it is implanted, a bone-growth-enhancing material, such as bone minerals, hydroxyapatite, whitlockite, or bone morphogenic proteins, may be deposited on the treated surface. The implant is preferably maintained in an oxygen-free environment following removal of the native oxide layer, in order to minimize the opportunity for oxide to re-form before the subsequent treatment is performed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagrammatic sectional view taken through a body of titanium covered with a layer of native oxide;
FIG. 2 is the same section shown in FIG. 1 after impacting the surface with a grit;
FIG. 3 is the same section shown in FIG. 2 after bulk etching with an acid etch;
FIG. 4 is the same section shown in FIG. 2 after first removing the native oxide and then bulk etching with an acid;
FIGS. 5A and 5B are scanning electron micrographs (“SEMs”) of two titanium dental implants prepared in accordance with the present invention;
FIGS. 6A and 6B are SEMs of the same implants shown in FIGS. 5A and 5B, at a higher magnification level;
FIG. 7 is a graph of the results of an Auger electron spectroscopic analysis of a titanium surface that has been exposed to air;
FIGS. 8A and 8B are SEMs of two titanium dental implants prepared in accordance with the present invention; and
FIGS. 9A and 9B are SEMs of the same implants shown in FIGS. 8A and 8B, at a higher magnification level.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Turning now to the drawings, and referring first to FIG. 1, a titanium body 10 which has been exposed to air has on its outer surface 12 an irregular layer 14 of an oxide or oxides of titanium which form naturally. This oxide layer 14 is referred to herein as the “native oxide” layer, and typically has a thickness in the range from about 70 to about 150 Angstroms. The native oxide layer that forms naturally on titanium when it is exposed to air is actually a combination of different oxides of titanium, including TiO, TiO 2 , Ti 2 O 3 and Ti 3 O 4 . The concentration of these oxides in the titanium body diminishes with distance from the surface of the body. The oxide concentration may be measured in an Auger spectrometer.
Auger electron spectroscopy (AES) measures the energy of Auger electrons produced when an excited atom relaxes by a radiationless process after ionization by a high energy electron, ion or x-ray beam. The spectra of a quantity of electrons emitted as a function of their energy reveal information about the chemical environment of the tested material. One of the major uses of AES is the depth profiling of materials, to reveal the thickness (depth) of the oxide layer on the surfaces of materials. These Auger electrons lie in an energy level that extends generally between the low energy level of the emission of secondary electrons up to the energy of the impinging electron beam. In this region, small peaks will occur in the spectra at certain energy levels that identify the existence of certain elements in the surface.
As used herein, the term “native oxide layer” refers to the layer which extends from the surface of the material to the depth at which the energy of the peak-to-peak oxygen profile as measured in an Auger electron spectrometer decreases by one-half. For example, in the peak-to-peak oxygen profile reproduced in FIG. 7, the thickness of the native oxide layer was 130 Angstroms, which is the depth at which the oxygen profile dropped to half its maximum intensity. Thus, removal of a 130-Angstrom layer from the surface of the titanium body would remove the native oxide layer.
FIG. 2 depicts the surface 12 of the titanium body 10 after being grit blasted to achieve initial roughening, as described in more detail below. The oxide layer 14 is still present, but it has a rougher surface than in its original state depicted in FIG. 1 .
FIG. 3 depicts the grit-blasted surface 12 of the titanium body 10 after it has been bulk etched in an etching acid. The etched area 16 where the native oxide layer 14 has been removed by the etching acid exhibits a much finer roughness, but in areas where the oxide layer remains, the initial roughness depicted in FIG. 2 also remains.
FIG. 4 depicts the grit-blasted surface 12 of the titanium body 10 after it has been etched in a first acid to remove the native oxide layer 14 , and then in a second acid to produce the desired topography on the surface 16 produced by the first acid treatment. As described in more detail below, the preferred surface topography has a substantially uniform, fine roughness over the entire surface 16 .
Among the processes previously used to improve the surfaces of dental implants made of titanium is that of etching the surface with an acid, such as a mixture of two parts (by volume) sulfuric acid and one part (by volume) muriatic acid. It has been found that such acid treatments do not etch an oxidized implant surface uniformly or consistently from one region to another.
According to one aspect of the present invention, the native oxide layer is removed from the surface of a titanium implant prior to the final treatment of the surface to achieve the desired topography. After the native oxide layer is removed, a further and different ‘treatment of the surface is carried out in the absence of unreacted oxygen to prevent the oxide layer from re-forming until after the desired surface topography has been achieved. It has been found that this process permits the production of unique surface conditions that are substantially uniform over the implant surface that is so treated.
Removal of the native oxide layer can be effected by immersing the titanium implant in an aqueous solution of hydrofluoric (HF) acid at room temperature to etch the native oxide at a rate of at least about 100 Angstroms per minute. A preferred concentration for the hydrofluoric acid used in this oxide removal step is 15% HF/H 2 O. This concentration produces an etch rate of approximately 200-350 Angstroms per minute at room temperature, without agitation, so that a typical native oxide layer having a thickness in the range from about 70 to about 150 Angstroms can be removed in about one-half minute. Other suitable etching solutions for removing the native oxide layer, and their respective etch rates, are:
50% HF—etch rate˜600 to 750 Angstroms/min.
30% HF—etch rate˜400 to 550 Angstroms/min.
10% HF—etch rate˜100 to 250 Angstroms/min.
A 100% HF was found to be difficult to control, and the etch rate was not determined. The preferred 15% HF solution allows substantially complete removal of the native oxide layer with minimum further consumption of the titanium surface after the implant is removed from the solution.
The native oxide layer may be removed by the use of other acids, or by the use of techniques other than acid etching. For example, the Swart et al. article cited above mentions the use of plasma cleaning to remove thin oxides. Regardless of what technique is used, however, it is important to remove substantially all the native oxide from the implant surface that is intended to interface with the living bone, so that the subsequent treatment of that surface produces a substantially uniform surface texture to promote uniform bonding to the living bone. The native oxide layer is preferably removed from substantially the entire bone-interfacing surface of the implant. In the case of screw-type dental implants, the bone-interfacing surface typically includes the entire implant surface beyond a narrow collar region on the side wall of the implant at the gingival end thereof. This narrow collar region preferably includes the first turn of the threaded portion of the implant. It is preferred not to etch the gingival end itself, as well as the narrow collar region, because these portions of the implant are normally fabricated with precise dimensions to match abutting components which are eventually attached to the gingival end of the implant. Moreover, it is preferred to have a smooth surface on that portion of a dental implant that is not embedded in the bone, to minimize the risk of infection.
The treatment that follows removal of the native oxide layer must be different from the treatment that is used to remove the native oxide layer. A relatively aggressive treatment is normally required to remove the oxide layer, and such an aggressive treatment does not produce the desired uniform surface texture in the resulting oxide-free surface. Thus, after the native oxide layer has been removed, the resulting implant surface is immediately rinsed and neutralized to prevent any further attack on the implant surface. The surface is then subjected to the further, and different, treatment to produce a desired uniform surface texture. For example, the preferred further treatment described below is a relatively mild acid-etching treatment which forms a multitude of fine cone-like structures having relatively uniform, small dimensions. Because of the prior removal of the native oxide layer, even a mild second treatment of the implant surface can produce a substantially uniform effect over substantially the entire bone-interfacing surface of the implant.
Prior to removing the native oxide layer, the oxide-bearing surface may be grit blasted, preferably with grit made of titanium or a dilute titanium alloy. As is taught in the aforementioned copending U.S. patent application Ser. No. 08/149,905, the use of a grit made of titanium avoids contaminating the surface of a titanium implant. Thus, for a dental implant made of commercially pure (“CP”) titanium, the blasting material may be CP B299 SL grade titanium grit. The preferred particle size for this grit is in the range from about 10 to about 60 microns (sifted), and the preferred pressure is in the range from about 50 to about 80 psi.
The surface treatment that follows removal of the native oxide layer from the implant surface may take several forms, singly or in combination. The preferred treatment is a second acid etching step, using an etch solution (“Modified Muriaticetch”) consisting of a mixture of two parts by volume sulfuric acid (96% by weight H 2 SO 4 , 4% by weight water) and one part by volume hydrochloric acid (37% by weight HCl, 63% by weight water) at a temperature substantially above room temperature and substantially below the boiling point of the solution, preferably in the range from about 60° C. to about 80° C. This mixture provides a sulfuric acid/hydrochloric acid ratio of about 6:1. This preferred etch solution is controllable, allowing the use of bulk etch times in the range from about 3 to about 10 minutes. This solution also can be prepared without the risk of violent reactions that may result from mixing more concentrated HCl solutions (e.g., 98%) with sulfuric acid. This second etching treatment is preferably carried out in the absence of unreacted oxygen, and before the implant surface has been allowed to re-oxidize, following removal of the native oxide layer. Of course, the implants may be kept in an inert atmosphere or other inert environment between the two etching steps.
The second etching step produces a surface topography that includes many fine projections having a cone-like aspect in the sub-micron size range. Because of the fine roughness of the surface, and the high degree of uniformity of that roughness over the treated surface, the surface topography produced by this process is well suited for osseointegration with adjacent bone. As illustrated by the working examples described below, the final etched surface consists of a substantially uniform array of irregularities having peak-to-valley heights of less than about 10 microns. Substantial numbers of the irregularities are substantially cone-shaped elements having base-to-peak heights in the range from about 0.3 microns to about 1.5 microns. The bases of these cone-shaped elements are substantially round with diameters in the range from about 0.3 microns to about 1.2 microns, and spaced from each other by about 0.3 microns to about 0.75 microns. The SEMs discussed below, and reproduced in the drawings, illustrate the surface topography in more detail.
The acid-etched surface described above also provides a good site for the application of various materials that can promote bonding of the surface to adjacent bone. Examples of such materials are bone-growth-enhancing materials such as bone minerals, bone morphogenic proteins, hydroxyapatite, whitlockite, and medicaments. These materials are preferably applied to the etched surface in the form of fine particles which become entrapped on and between the small cone-like structures. The bone-growth-enhancing materials are preferably applied in the absence of oxygen, e.g., using an inert atmosphere.
The roughness of the surface to which these materials are applied enhances the adherence of the applied material to the titanium implant. The uniformity of the rough surface enhances the uniformity of the distribution of the applied material, particularly when the material is applied as small discrete particles or as a very thin film.
A preferred natural bone mineral material for application to the etched surface is the mineral that is commercially available under the registered trademark “BIO-OSS”. This material is a natural bone mineral obtained from bovine bone; it is described as chemically comparable to mineralized human bone with a fine, crystalline biological structure, and able to support osseointegration of titanium fixtures.
The invention will be further understood by reference to the following examples, which are intended to be illustrative and not limiting:
EXAMPLE NO. 1
A batch of 30 screw-type cylindrical implants made of CP titanium were grit blasted using particles of CP B299 SL grade titanium grit having particle sizes ranging from 10 to 45 microns, at a pressure of 60 to 80 psi. After grit-blasting, native oxide layer was removed from the implant surfaces by placing 4 implants in 100 ml. of a 15% solution of HF in water at room temperature for 30 seconds. The implants were then removed from the acid, neutralized in a solution of baking soda, and placed in 150 ml. of “Modified Muriaticetch” (described above) at room temperature for 3 minutes. The implants were then removed from the acid, neutralized, rinsed and cleaned. All samples displayed very similar surface topographies and a high level of etch uniformity over the surface, when compared with each other in SEM evaluations. Consistency in the surface features (peaks and valleys) was also observed. The SEMs in FIGS. 5A, 5 B, 6 A and 6 B show the surfaces of two of the implants, Sample A-1 and Sample A-4, at magnifications of 2,000 and 20,000. It will be observed that the surface features over the areas shown are consistent and uniform. The scale shown on the X20,000 photographs is 1 micron=0.564 inch. At this magnification the surfaces appear to be characterized by a two-dimensional array of cones ranging in height (as seen in the SEMs) from about 0.17 inch to about 0.27 inch; the base diameters of these cones varied from about 0.17 inch to about 0.33 inch. Converting these numbers to metric units on the above-mentioned scale (1 micron=0.564 inch) yields:
cone height range (approx.)=0.30 to 0.50 micron
cone base diameter range (approx.)=0.30 to 0.60 micron.
The same degree of uniformity was found in all the samples, and from sample to sample, at magnifications of 2,000 and 20,000, as compared with similar samples subjected to bulk etching without prior removal of the native oxide, as described in EXAMPLE NO. 2 below.
EXAMPLE NO. 2
Four of the implants that had been grit blasted as described in EXAMPLE NO. 1 above were placed in 150 ml. of “Modified Muriaticetch” for 10 minutes. The implants were then removed, neutralized, rinsed and cleaned. SEM photographs taken at magnifications of 2,000 and 20,000 showed that the bulk etch solution failed to remove the native oxide layer after 10 minutes in the etch solution. The failure to remove the native oxide layer (100-150 Angstrom units thick) resulted in a non-uniformly etched surface, as depicted in FIG. 3 . In areas of the implant surfaces where the native oxide was removed, the topography was similar to that observed on the implants in EXAMPLE NO. 1.
EXAMPLE NO. 3
The procedure of this example is currently preferred for producing commercial implants. A batch of screw-type implants made of CP titanium were immersed in a 15% solution of HF in water at room temperature for 60 seconds to remove the native oxide layer from the implant surfaces. A plastic cap was placed over the top of each implant to protect it from the acid. The implants were then removed from the acid and rinsed in a baking soda solution for 30 seconds with gentle agitation. The implants were then placed in a second solution of baking soda for 30 seconds, again with agitation of the solution; and then the implants were rinsed in deionized water. Next the implants were immersed in another solution of two parts by volume sulfuric acid (96% by weight H 2 SO 4 , 4% by weight water) and one part by volume hydrochloric acid (37% by weight HCl, 63% by weight water) at 70° C. for 5 minutes. The implants were then removed from the acid and rinsed and neutralized by repeating the same steps carried out upon removal of the implants from the HF. All samples displayed very similar surface topographies and a high level of etch uniformity over the surface, when compared with each other in SEM evaluations. Consistency in the surface features (peaks and valleys) was also observed. The SEMs in FIGS. 8A, 8 B, 9 A and 9 B show the surfaces of two of the implants, Sample 705MB and Sample 705MC, at magnifications of 2,000 and 20,000. It will be observed that the surface features over the areas shown are consistent and uniform. The scale shown on the X20,000 photographs is 1 micron=0.564 inch. At this magnification the surfaces appear to be characterized by a two-dimensional array of cones ranging in height (as seen in the SEMs) from about 0.17 inch to about 1.128 inch; the base diameters of these cones varied from about 0.17 inch to about 1.128 inch. Converting these numbers to metric units on the above-mentioned scale (1 micron=0.564 inch) yields:
cone height range (approx.)=0.30 to 2.0 microns
cone base diameter range (approx.)=0.30 to 2.0 microns.
The same degree of uniformity was found in all the samples, and from sample to sample, at magnifications of 2,000 and 20,000, as compared with similar samples subjected to bulk etching without prior removal of the native oxide, as described in EXAMPLE NO. 2 above. | The surface of a device that is surgically implantable in living bone is prepared. The device is made of titanium with a native oxide layer on the surface. The method of preparation comprises the steps of removing the native oxide layer from the surface of the device and performing further treatment of the surface substantially in the absence of unreacted oxygen. | 2 |
BACKGROUND AND SUMMARY OF THE INVENTION
The invention relates to a modular construction system for producing a plurality of design variants of a roof module and to a method for producing such roof modules.
Modular production techniques are being increasingly used in motor car construction, wherein certain component groups are separately joined away from the main production line and then incorporated as a finished module again into the main production line. In particular, the production of roof modules according to this principle can be derived from the prior art as generally known. A plurality of roof variants is generally offered for a motor car type, for example solid roofs, sliding roofs, panoramic roofs and the like. To date the roof modules for these design variants have also differed in how they were connected to the rest of the motor car shell. Panoramic glass roofs for example are generally stiffened with a sheet metal frame and adhesively bonded into the shell from above. Other roof variants are joined to the shell from below and often require additional assembly parts and greater assembly expenditure.
For different roof variants of a motor car, therefore, it is disadvantageous that a plurality of assembly stations must be provided in the main production line as each roof variant, as described, is connected to the shell of the motor car in a different way.
Exemplary embodiments of the present invention provide a modular construction system and a method for producing a roof module, with which different design variants of roof modules can be produced that can be connected to a motor car shell in the same way.
Such a modular construction system serves for the production of a plurality of design variants of a roof module for a motor car. In this regard, a plurality of design-variant-specific adapter elements and a plurality of design-variant-specific planar elements are provided. By means of respectively at least one adapter element a respective planar element can be connected to a frame, forming a roof opening, in particular of a shell of the motor car. The adapter elements create a uniform connection interface between the roof and the shell in such a way that all roof modules that can be produced using the modular construction system can be connected to the motor car shell in the same way. It is thus no longer necessary—as known from the prior art—for each design variant to have its own installation station for the roof module in the motor car shell. Instead, all different modules can be incorporated in the same way into the shell. Both production time and production costs can thereby also be advantageously spared.
The design-variant-specific planar elements hereby include preferably planar elements for sliding roofs and/or panoramic glass roofs and/or lifting and sliding roofs and/or solid roofs. All common design variants of motor car roofs can thereby be advantageously realized by means of one and the same modular construction system. A design-variant-specific cover part is thereby produced from the combination of at least two respective planar elements.
The design-variant-specific adapter elements are preferably formed as frames. It is particularly preferable for the adapter elements to be separated into a front and a rear part frame that abut or overlap in the region of the B pillar of the motor car. In order to achieve an additional stiffening of the roof it is possible for an additional transverse reinforcing element to be provided in this area. A respective design-variant-specific cover part is also preferably separated in the region of the B pillar into a front and rear planar element, as in particular the rear region of the cover part often has no differences between different design variants. For example, a sliding roof and a lifting and sliding roof have the same rear planar element. Accordingly, the front planar elements comprising the actual sliding roof or lifting and sliding roof function must be differently formed in the two design variants.
In a further embodiment of the invention a plurality of design-variant-specific functional elements are provided which can be connected to at least one adapter element and/or one planar element. It can hereby be a matter of the actual cover mechanism for moving a sliding roof, an electric drive for movable parts of the roof, window shades, wind deflectors, guide rails or similar.
The invention further relates to a method for producing a roof module for a motor car from a plurality of design variants. Initially, a frame forming a roof opening is provided, in particular of a motor car shell, and then a planar element is selected from a plurality of design-variant-specific planar elements depending upon the desired design variant. In order to connect the planar element to the frame, at least one adapter element assigned to the selected planar element is selected in the next step from a plurality of design-variant-specific adapter elements and the planar element is connected to the frame by means of said adapter elements. The connection of adapter elements and planar elements is preferably thereby carried out by adhesive bonding.
As already described in relation to the modular construction system, the assembly of roof modules of different design variants on the motor car shell can be made uniform so that the number of necessary work stations in the main production line can be reduced.
BRIEF DESCRIPTION OF THE DRAWING FIGURES
The invention and its embodiments will be described in greater detail below by reference to the drawings, in which:
FIG. 1 shows a frame of a motor car shell structure for incorporation of a roof module produced with an exemplary embodiment of the inventive modular construction system;
FIG. 2 shows adapter elements for an exemplary embodiment of an inventive modular construction system;
FIG. 3 shows functional elements for an exemplary embodiment of an inventive modular construction system;
FIG. 4A-4C show design-variant-specific planar elements and cover parts formed therefrom for an exemplary embodiment of an inventive modular construction system; and
FIG. 5 illustrates a sliding roof, panoramic glass roof, lifting and sliding roof, and a solid roof.
DETAILED DESCRIPTION
The shell of a motor car forms—as shown in FIG. 1 —a frame 10 for receiving a roof module. This comprises two longitudinal beams 12 and two transverse beams 14 .
In order to be able to provide different design variants of the roof module—as shown in FIG. 2 —adapter elements 16 , 18 are connected to the frame 10 formed as part of the shell. The adapter elements 16 , 18 are thereby formed as frame-like plastic elements which respectively extend approximately over half of the longitudinal extension of the roof module, are aligned and thus separated in the installation position of the roof module approximately in the region of the B pillar of the motor car. The frame-like adapter elements 16 , 18 respectively comprise large openings 16 a , 18 a that can optionally be covered in a transparent or openable manner. Likewise, in the region of the B pillar and thus between the adapter elements a glass element 20 can be arranged for additional reinforcing of the roof module. The adapter elements 16 , 18 serve firstly for the further stiffening of the roof module and secondly in particular for connection of different planar and functional elements to the frame 10 . For all design variants of the roof module a uniform connection geometry to the shell is provided by the adapter elements 16 , 18 , whereby all design variants can thereby be connected in a single work station in the main production line to the frame 10 and thus to the shell.
After assembly of the adapter elements 16 , 18 on the frame 10 additional functional components 22 —an overview of which is shown in FIG. 3 —are connected to the roof module. It is hereby a question of drive motors 24 for driving sliding roofs, corresponding rail systems 26 , in which the sliding roofs run, guide rails 28 and also sunshades 30 . The necessary functionality for movable design variants of the roof module is thus provided.
In the final assembly stage the planar elements, which close the roof module outwardly and together form a respective design-variant-specific cover part, are assembled on the structure present thus far. FIG. 4A shows a cover part 32 for a panoramic glass roof. The cover part 34 is divided into two in the region of the B pillar and comprises a front planar element 34 and a rear planar element 36 which are respectively formed transparently. In the region of the abutment 38 between the planar elements 34 and 36 , for example, the reinforcement shown in FIG. 2 can be carried out through the transverse bow 20 . An only partially transparent or opaque solid roof can also be produced through corresponding selection of the planar elements 34 , 36 in this way.
FIG. 4B shows a cover part 40 for a sliding and lifting roof that is also divided into two. The rear planar element 42 is thereby designed in the usual way as a sheet metal outer shell, the front planar element 43 contains the actual outward movement mechanism so that the sliding and lifting roof can be moved out in the direction of the arrow 44 .
FIG. 4C shows a cover part 46 for an outwardly extending sliding roof, wherein on the front adapter element 16 , which comprises the passage opening 16 a , a displaceable roof element 52 is arranged that can initially be moved out in the direction of the arrow 54 and then displaced in the direction of the arrow 56 towards the rear via a rear planar element which is hidden in the illustration shown.
All cover parts can—as shown in FIG. 4 A-C—be designed in two parts. It is also possible, however, to design them in one part.
The respective rear planar elements 36 , 42 of the three variants shown in FIG. 4 are arranged via the respective adapter element 18 in a fixed manner on the motor car roof. The planar elements can thereby be transparent or translucent and consist of an extensively free choice of materials from glass, plastic or sheet metal. The front planar element 43 , 52 can be movable and in particular be designed to open.
It is particularly advantageous to design the roof modules so that they can be introduced, preferably adhesively bonded, from above into a vehicle shell. This simplifies the assembly and reduces the required construction space so that the headroom for vehicle occupants is improved. In comparison with roof modules incorporated from below the water drainage into the wet area shell is also possible so that additional water discharge hoses can be omitted.
FIG. 5 illustrates a sliding roof 505 , panoramic glass roof 510 , lifting and sliding roof 515 , and a solid roof 520 .
The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof. | A modular construction system for producing a plurality of design variants of a roof module for a motor car includes a plurality of design-variant-specific adapter elements and a plurality of design-variant-specific planar elements. Using at least one adapter element, at least one respective planar element can be connected to a frame, forming a roof opening, in particular of a motor car shell. | 8 |
This application corresponds to the U.S. national phase of Patent Cooperation Treaty application No. US97/01754, filed Jan. 31, 1997 under 35 U.S.C. §371, which claims priority of U.S. patent application Ser. No. 08/595,277, filed Feb. 1, 1996 now abandoned, the entire contents of both of which are incorporated herein by reference.
FIELD OF THE INVENTION
This invention relates generally to arthroplasty and, more particularly to devices and techniques for positioning a prosthesis prior to fixation through the injection of a bonding agent.
BACKGROUND OF THE INVENTION
In current human joint repair situations, it is common practice to prepare host bone stock to receive an implant then, if satisfied with the physical correspondence, apply cement to the host, install the prosthesis, and stabilize the arrangement until curing. This approach has several disadvantages. Foremost among them arises from the unpredictable process of ensuring that, although the prosthesis may have been ideally placed prior to cementation, once the cement is applied, orientation may shift, resulting in a final configuration which is less than optimal.
A few approaches have been attempted to assist in making the positioning of the final implant more predictable. As discussed further in the detailed description herein, one such approach utilizes a centralizing plug inserted distally within the medullary canal, and from which there extends a rod upon which a final implant including a corresponding central bore may be monorailed. The plug and rod are positioned in conjunction with a trial which also includes a central bore, which is then removed, the intramedullary cavity filled with cement and the final implant slid over the rod, displacing the cement as it is pushed down into position. Although this technique may assist in maintaining a side-to-side orientation prior to cementation, it does not address the simultaneous need for up-and-down and/or rotational stabilization. Additionally, as with current techniques, cement is applied to the host prior to the introduction of the final implant, leaving open the possibility that the final implant may be held in a position different from that associated with the trial, and may therefore result in an unacceptable misplacement as the cement cures.
Other approaches do reverse this order, and install the final implant prior to the injection of cement. The known approaches, however, utilize a highly specialized prosthetic device including centralizing protrusions and internal channels through which the cement is introduced. That is, in these systems, the prosthesis itself is used as the cement injector. Due to their requirement for a highly specialized final prosthetic element, such systems are incompatible with currently available implant devices, and therefore raise costs while reducing the options of the practitioner. In addition, they do not adequately address the need for simultaneously stabilizing multiple degrees of freedom prior and during cementation. As a further disadvantage, the systems which use the prosthesis as the cement injector tend to use the cement as a grout between the outer surface of the implant and the inner surface of the receiving cavity. It has been shown, however, that the changes of success are improved through the creation of a thicker cement “mantle,” as opposed to a thin grout-type layer. The need remains, then, for a system whereby the prosthesis may be stabilized relative to multiple degrees of freedom prior to cementation, and, ideally, remain compatible with existing prosthetic components while forming a strong and stable bond to the host.
SUMMARY OF THE INVENTION
The present invention resides in apparatus and methods for maintaining the proper positioning of a prosthetic implant having proximal and distal ends within a prepared bone cavity during cement injection and curing. In contrast to prior-art systems the invention provides first stabilization means, implantable within the bone cavity, for minimizing lateral movement of the distal end of the implant, and second stabilization means, physically separate from the means for minimizing lateral movement of the distal end of the implant, for minimizing both the lateral movement of the proximal end of the implant and the rotational movement of the implant overall. In the preferred embodiment, the second stabilization means includes an apertured cap removably securable to the end of a bone having the prepared cavity through which the implant is inserted and held in place. This cap, which may either be entirely rigid or include a pliable membrane in the vicinity of the aperture, preferably further includes a first port associated with cement injection and a second port associated with cement over-pressurization. In an alternative embodiment, the second stabilization means includes a manually operated mechanism enabling the implant to be temporarily yet rigidly secured thereto in accordance with a desired orientation, preferably affording adjustments along multiple degrees of freedom prior to the rigid securement thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A illustrates, in skeletal form, the first step of a prior-art implantation sequence involving host bed preparation;
FIG. 1B depicts an intermediate step in the prior-art sequence wherein the cavity prepared according to FIG. 1A is filled with cement;
FIG. 1C illustrates the final phase of this prior-art sequence wherein a femoral prosthesis is inserted into the injected cement prior to hardening;
FIG. 2A illustrates a prior-art improvement over the sequence shown in FIGS. 1A through 1C, wherein a distal plug is used for distal centering of the implant;
FIG. 2B illustrates yet another prior-art improvement over the approach of FIG. 2A wherein a vertically oriented rod is attached to the distal plug over which an implant may be slid after cement injection to further inhibit movement during curing;
FIG. 3 is an arrangement according to this invention showing the use of a proximal cap which may be used either with a specially prepared prosthetic device or commercially available unit;
FIG. 4 illustrates two independently usable alternative embodiments according to the invention, including a multiple degree-of-freedom proximal retainment structure and a distal plug including leaf springs;
FIG. 5 is a drawing which shows, from an oblique perspective, an alternative embodiment of the invention which clamps around the femur below the area of resection, and attaches to an elongated fastener oriented generally lengthwise with respect to the implant;
FIG. 6 is a drawing which shows how the invention could be applied to a humeral prosthesis; and
FIG. 7 is a drawing which shows how the invention may be applied to knee arthroplasty.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 of U.S. Pat. No. 5,340,362 shows an existing, prior-art procedure for inserting and cementing a prosthesis into a bone cavity, and this figure has been reproduced herein. In accordance with this technique, the canal is reamed or broached as shown in FIG. 1A, and a trial is typically inserted thereinto to ensure that the final prosthetic component will be properly received. After this trialing, cement is injected into the excavated area as shown in FIG. 1B, and the prosthesis is inserted as shown in FIG. 1C, and left in position while the cement hardens. As discussed in the background of the instant invention, the technique just described is deficient in that, although the prosthesis may be optimally oriented during the trial procedure, the position of the actual implant may shift upon insertion into the cemented host or thereafter, resulting in a misaligned final fixation.
Various improvements also exist in the prior art to minimize such adjustment problems. At the very least, as shown in FIG. 6 of U.S. Pat. No. 4,994,085, reproduced herein as FIG. 2A, a distal centralizer 16 is inserted beforehand into the intramedullary cavity 13 to which the distal tip 17 a of the implant 17 engages at point 16 a . This, at least, stabilizes the relative position of the distal tip 17 a , resulting in a narrower range of angles (A to B) through which the implant 17 may move within the cement-filled cavity prior to final curing. The teachings of this reference further improve upon post-cementation stabilization by incorporating a stabilizing rod 4 into the distal plug 6 over which a specially designed implant 2 having a centralized hole 4 is slidably installed, as shown in FIG. 2B herein (FIG. 4 of the issued patent). Assuming the various connections between rod 5 , plug 6 and the inner walls of the intermedullary canal are relatively rigid, and the various tolerances involved are substantially tight, movement of the implant 2 is further restricted until the cement finally cures.
Another approach taken according to the prior art involves the injection of cement after positioning of a specially designed implant into a prepared cavity. The '362 patent referenced above is directed toward such an approach. As with other arrangements of type, the final implant includes a cement canal along its longitudinal axis. A bone-cement injector is threaded onto the proximal portion of this cement canal, causing the cement to subsequently travel down and through the implant, eventually exiting through openings in and around its distal tip. A restrictor plug halts downward cement travel, thus initiating an upward, retrograde filling of the void in between the prosthesis and the cancellous bone wall. In addition to a single distal aperture through which the injected cement is introduced, side ports may also be included, as shown in U.S. Pat. No. 4,274,163 and various other prior-art references.
The methods and associated apparatus just described exhibit various shortcomings. In the technique described with reference to FIG. 2B herein, although movements within the curing cement bed are further restricted, the point of substantial stability remains at the distal tip of the implant, enabling a certain level of proximal misalignment to continue, as no true proximal stabilization is provided. Worse, perhaps, is that since the centering rod and bore through the specialized component are both circular, the final implant is still subject to up-and-down and/or rotational variation, resulting in potential misalignment upon fixation.
With respect to the techniques wherein cement is injected after installation, although the implant may be stabilized both proximally and distally as the cement is injected, as with the device of the '085 patent, a specially designed implant including the injector ports must be utilized, resulting in a specialized unit demanding significantly higher cost. Furthermore, regardless of the existing system utilized, attention to the pressure of the cement during injection and curing has not been adequately addressed. Although, for example, the system described in the '163 patent referenced above utilizes various components to maintain pressurization, numerous sophisticated articles are required, including a high pressure nitrogen gas source, disposable cylinder and various associated valves and tubing which may be difficult to assemble, require skilled operators, or create expensive waste and maintenance problems.
The present invention improves upon the prior art by providing a simplified apparatus and associated installation methods whereby an implant may be oriented both proximally and distally prior to the injection of cement, while, at the same time, providing means for guarding against rotational and up/down movement of the implant as well during such injection and subsequent curing. In addition, configurations according to the invention provide a simple means for expelling over-pressurized cement, thereby yielding a simple, but satisfactory indication that sufficient cement has been injected to an acceptable level. Although, in one embodiment, the invention makes advantageous use of a longitudinal bore through the implant, in another embodiment, all of the above improvements and advantages are realized in conjunction with standard, currently available prostheses, thus resulting in an approach which is both straightforward and economical.
FIG. 3 is an oblique drawing of an arrangement according to this invention depicting various independent embodiments. Overall, an implant 310 is shown inserted into a prepared cavity 312 , in this case the implant 310 being a femoral hip prosthesis and the cavity 312 being the intramedullary canal, though, as will be apparent to those of skill in the art of orthopaedics, the general principles disclosed herein are not restricted to this application, and may be used in other joint situations, including the knee (FIG. 7 ), shoulder (FIG. 8) and other situations. Certain features of the femur are shown such as the greater trochanter 313 and lesser trochanter 315 , and it is assumed that a resection not visible in this figure has been performed on at least a portion of the proximal end of the femur along with reaming and other preparation of the medullary canal itself to accept the implant 310 .
Broadly, according to the invention, an apertured proximal sealing cap is installed over the resection portion of the femoral shaft, the prosthesis 310 is inserted through the proximal opening 320 of the seal, and cement is injected through an injection port 322 . In a preferred embodiment, this proximal seal includes a horseshoe-shaped collar 330 having one or more means such as thumb screws 332 for releasably securing the collar 330 over the bone, and a preferably pliable gasket 334 made from rubber or other suitable polymeric materials through which the aperture 320 is formed. Also located on and through this gasket 334 is a flap valve 336 wherein the material forming the gasket 334 is adjusted to flap open or rupture at a predetermined pressure level, preferably on the order of 25 mm of mercury, which has shown to be advantageous for such orthopaedic purposes. Preferably, this flap valve 336 is formed either by scoring the material of the gasket 334 in a manner conducive to such rupture, or, alternatively, the material may be thinned in this area to break under load.
The embodiment of the proximal seal just described is that preferred for use in conjunction with standard, commercially available implants. That is, the aperture 320 formed in the gasket 334 may take the form of a slit, an oval, or another shape appropriate to the stem of the implant, enabling the device to be inserted therethrough and retained in place by the surrounding material of the gasket 334 against the stem, either through friction or high-tolerance. Alternatively, then, if a more precise geometry of the stem at the point where it emerges through the proximal seal is known, the material 334 may be of a more rigid composition, and may, in fact, be integrally formed to the collar 330 , in which case the injection port 322 and valve 336 may be more elaborate and substantial. For example, if the area 334 is metal, the port 322 may be threaded for a more solid connection to commercially available injector nozzles, and the valve 336 may take advantage of more sophisticated pressure-release techniques available in the art, including adjustability for a particular pressure or range of pressures.
Whether the implant is of a standard configuration or specialized for use in conjunction with the invention, a distal spacer 340 is preferably utilized for distal centering. A longitudinal rod 342 may optionally be added to, or installed on the plug 340 , requiring a specialized implant having a longitudinal bore 344 akin to that described in the '085 patent referred to above, the exception being that, according to this invention, the implant 310 would be monorailed onto the optional rod 342 prior to the injection of cement into the cavity formed between the walls of the implant and the prepared medullary canal. Thus, as discussed above, the present invention may either be used with a specially prepared implant having this longitudinal bore and/or convenient wall geometries or, alternatively, and unlike the prior art, a standard prosthesis may be used.
In the event that the prosthesis includes an arrangement to assist in installation or removal such as ring 350 , the alternative proximal stabilization configuration of FIG. 4 may be used. To further assist in proximal securement, a multiple degree-of-freedom clamp arrangement illustrated generally at 404 may be attached to a proximal cover 406 secured to femoral end or attached to a portion of available bone material by whatever means. In the embodiment shown, a first rod 408 securely affixed to the member 406 at point 409 , onto which there is disposed a slidable collar 412 which may be locked into position with a suitable device such as thumb screw 414 . A second rod 420 and collar 422 contains two thumb screws, one to lock the collar 422 in position along rod 420 , and a different thumb screw 430 for positive engagement with the prosthesis proper. It will be understood to those of skill that various other approaches may be utilized in accordance with the general principle contained herein to grasp and hold any portion or aperture of a standard implant without requiring its modification.
FIG. 4 also shows an alternative distal plug according to the invention which may be used in combination with any of the embodiments previously described. With such an inventive plug, it is first seated distally at an appropriate distance within the intermedullary canal, and includes a plurality of deformable upwardly oriented leaf springs 490 . Accordingly, with the plug 480 installed in place as shown, an even more generalized type of implant, and not requiring an actual, solid connection to such a distal spacer, may be inserted down and into the medullary canal and held in place while resisting distal side-to-side motion as the distal tip of the implant is retained within these leaf springs 490 . This also allows adjustments in a longitudinal direction enabling fine tuning at the effective length of the implant. Note in FIG. 4 that the aperture through which the implant is inserted is quite a bit larger than that shown in FIG. 4 and, in fact, does not include a seal per se. This is due to the fact that, in accordance with this embodiment, cement may, in fact, be injected prior to or after the implant is held in place both proximally and distally. Indeed, according to this particular embodiment, a standard distal plug may be used in conjunction with the mechanism shown generally at 404 even without a cap or collar as shown. For example, this mechanism 404 may simply attach to an existing bone surface or structure instead of the point 409 , thereby holding the implant in place proximally and distally while preventing motion in all dimensions as the cement cures, regardless of when it was injected. In accordance with an alternative methodology, the proximal and distal stabilizers may be used in conjunction with a trial then, upon achieving a desired orientation, a single manual fastener may be loosened, and the actual implant installed in the exact configuration of the trial to guarantee proper positioning.
FIG. 5 illustrates an alternative embodiment of the invention, seen generally at 502 from an oblique perspective. In this case, a prosthesis 504 , which may have a threaded bore along an axis 508 to receive a threaded fastener such as a bolt 506 , is physically coupled to a first structural element 520 which slidably engages with a collar 530 , and which may be tightened in place with a manual fastener such as thumb screw 532 . Other types of fasteners, including those requiring tools such as set screws, may alternatively be utilized for this purpose. In this embodiment, the prosthesis 504 may be rotated about the axis 508 with the bolt 506 in a slightly loosened condition, and then tightened when a desired angular rotation is achieved. A score mark 522 may be used in conjunction with score marks 524 to provide an indication of this desired angular rotation for future reference. Preferably, score marks are provided on the underside of member 520 as well in the vicinity of the attachment to the prosthesis, to assist in maintaining the desired rotational configuration once the bolt 506 is tightened. Prosthetic devices having a threaded bore along axis 508 are available from the Zimmer Company, though in the event that such a feature is not provided for, connection may be made to the prosthetic element itself as disclosed elsewhere herein, rendering this threaded bore convenient but not necessary to the invention.
Preferably in this embodiment a set of score marks 526 are also provided on the member 520 , such that with the member 520 being moved back and forth to adjust the lateral or transverse positioning of the implant, the fastener 532 may be used to lock the configuration in place, with the marks 526 being used to maintain a visual indication of the desired lateral configuration. Attached to collar 530 is a downwardly extending member 540 , which is received by a collar 544 having a manual adjustment device 546 . The member 540 may also include markings 542 , such that, as the element 540 is moved up and down to adjust for the axial length of the prosthesis, fastener 546 may be locked with the score marks 542 providing a visual indication.
The collar 544 is attached to a clamp 550 , which is rigidly attached to the outer surface of the femur through manual fasteners 552 and 554 . As a further optional convenience, the collar 544 may be rotationally variable, and locked into place along with member 540 with manual fastener 546 , with optional score marks 560 being used as a visual indication of this configuration, if so desired.
Although the various embodiments of this invention may be used to properly position a trial implant prior to the positioning of a final prosthetic element, it should be apparent that in all cases, the device such as 504 in FIG. 5 is assumed to be the final implant itself, thereby eliminating the need for a trial. Particularly if the various positioning elements of the invention are sufficiently low in profile, the entire assembly, including those shown in the figures, joint reduction may be carried out, with the various fasteners being adjustably and rigidly clamped, with the final implant positioned in place and rigidly connected thereto. Following this procedure, the properly positioned implant may be removed from its reduced configuration and cemented. According to the invention, depending upon the circumstances, the prosthesis may be cemented in situ , with the various positioning members according to the invention remaining locked in place, or, alternatively, one or more of the fasteners may be loosened, with the implant and, perhaps, other fasteners attached thereto, removed and repositioned once cement has been injected into the intramedullary canal.
For example, referring to the embodiment of FIG. 5, fastener 546 may be slightly loosened, with the prosthesis 504 and members 520 and 540 rigidly attached thereto being temporarily removed, the cavity filled with cement, and the prosthesis with members 520 and 540 reinserted, with member 540 being reinstalled into collar 544 , utilizing the score marks 542 to ensure that fixation will take place at a proper and desired orientation upon re-tightening of the fastener 546 . It will also be apparent that in the embodiment of FIG. 5 and others disclosed herein, that if the assembly attached to the femur and to the prosthetic element through using one or more structural elements according to the invention is sufficiently rigid, positioning of the final implant may be stabilized in three dimensions (for example, rotationally, transversely, and axially—i.e., with respect to the coronal, sagittal and transverse planes). | Apparatus and method are disclosed for maintaining the proper positioning of an implant ( 310, 504 ) within a prepared bone cavity ( 312 ) during cement injection and curing. First stabilization means ( 340, 480 ), implantable within the bone cavity, minimize lateral movement of the implant distal end, while second stabilization means ( 330, 334, 406, 404 ), physically separate from the first stabilization means ( 340, 480 ), minimize both the lateral movement of the implant proximal end and the rotational movement of the implant overall. In the preferred embodiment, the second stabilization means ( 330, 334 ) includes an aperture cap ( 334 ) removable securable to the end of a prepared bone. This cap ( 334 ), preferably further includes first and second ports ( 322, 336 ) associated, respectively, with cement injection and cement over-pressurization. In an alterative embodiment, the second stabilization means ( 406, 404 ) includes a manually operated mechanism enabling ( 404 ) the implant ( 504 ) to be temporarily, yet rigidly, secured thereto in accordance with a desired orientation, preferably affording adjustments along multiple degrees of freedom prior to the rigid securement thereof. | 0 |
BACKGROUND OF THE INVENTION
This invention relates to a board game which uses a map of the United States of America (U.S.) in which the players try to construct roads between cities.
Games, including board games, that employ maps are well known and have been used for many years. For example, in one earlier game there is a map of selected countries and a path placed on the board. The first player to traverses the path wins. Another prior art game discloses a map of the U.S. and simulates the operation of a trucking company.
In another game with a map fictitious continental regions and players are disclosed with the players earning points through the use of game cards. Another game discloses a map showing areas of Europe and players earning points by moving from city to city.
Still another game discloses a map of the U.S. and simulates a family vacation.
DESCRIPTION OF THE PRIOR ART
Games that employ maps are disclosed in the known in the prior art. For example, U.S. Pat. No. 4,095,800 to Konsolas discloses a map of selected countries and a path placed on the board. The first player to traverses the path wins.
U.S. Pat. No. 4,643,430 to D'Aloia discloses a map of the U.S. and simulates the operation of a trucking company.
U.S. Pat. No. 4,733,870 to Rinehart discloses a map with fictitious continental regions and players with the players earning points through the use of game cards.
U.S. Pat. No. 4,961,582 to Van Lysel discloses a game with a map showing areas of Europe and players earning points by moving from city to city.
U.S. Pat. No. 5,405,140 to Terlinden et al. discloses a map of the U.S. and simulates a family vacation.
In the present invention is a game which uses a map of the U.S. with the players trying to construct roads at random locations all as will be detailed in the specification that follows hereafter.
SUMMARY OF THE INVENTION
This invention relates to a game which uses a map of the U.S. with the players trying to construct roads at random locations. Four cities on the map are selected at random, the first to construct roads between their cities wins the game using selected cards and overcoming other obstacles.
It is the primary object of the present invention to provide for an improved board game having a map of the U.S. and selected cities.
Another object is to provide for such a game in which each player is randomly assigned cities using the first deck of cards while a second card deck provides for action and frustruction directions to help or delay the winning of the game according to the rules.
These and other objects and advantages of the present invention will become apparent to readers from a consideration of the ensuing description and the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the board game of the present invention showing the map of the U.S. with some playing pieces placed on the board.
FIGS. 2-8 are views of the game board pieces used with the FIG. 1 game board.
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 is a perspective view of the board game 1 of the present invention showing a map 3 of the states for the contiguous U.S. with some playing pieces placed on the board. The board 1 is rectangular in shape and may be foldable for storage or transport purposes. The adjacent portions of the countries of Mexico 5 and Canada 7 are also shown on the board. Within the map 3 each of the forty eight states are outlined in different colors with roads traversing the states to some selected cities located in that or an adjacent state. All of the depicted states are represent in size and shape in relation to each other with Texas 9 being the largest shown and Rhode Island 11 the smallest. In one embodiment 32 distinct cities are shown on map 3 at their locations within the states in which actually located, for example, New York City 13 and Los Angeles 15 . A large O may be used to represent the city space and a rectangle (v) for road space on the map. As an example, one road between two cities is marked with both a 17 and a V . Interconnecting each of the distinct cities are roads 17 with road space, like Interstate Highway 10 from Phoenix, AZ 19 to San Diego, Calif. 21 . This is but one example used to mark both the location of a road 17 and the space for the road V. Each of the road connected cities selected is marked by a O.
In addition to the shown states, selected cities, connecting roadways, and other well known geographical representations, like the great lakes, rivers, Gulf of Mexico and Oceans, the map 3 may have certain playing pieces and/or markers placed on its surface. As described in more detail with respect to FIGS. 2-8, the playing pieces consist of two decks of cards and the playing markers consists of City Markers, Road Closed Markers, Intersection Markers, Player tiles (five different colors) and Detour Markers. On the map there are: three Intersection Markers 23 shown standing upright on the map, three Road Closed Markers 25 , three City Markers 27 , three Player tiles 31 of three different colors, and two Detour Markers 33 . Playing cards 35 are also shown in FIG. 1. A City Peg , not shown, may also be used.
FIGS. 2-8 are views of the game board pieces used with the FIG. 1 game board. The previous mentioned playing pieces and markers are shown in greater detail including the intersection Marker 23 (FIG. 5) with different colored signal lights on four sides of the marker, the Road Closed Marker 25 (FIG. 4 ), a City Marker 27 (FIG. 3 ), one of five individual colored Player tiles 31 (FIG. 7 ), the Detour Marker 33 (FIG. 8) and a safe passage tile 41 (FIG. 6 ). Another possible playing piece, The City Peg, is not shown. The two decks of playing cards designated as playing pieces 35 shown in FIG. 1 may be broken down into two sub decks marked Frustruction 37 and City Card 39 . There are four distinct different sets of color markers used with their two sub decks . In the preferred embodiment, there are twenty four City Markers (4 of each different color), 18 City Markers pegs (3 of each different color), 240 road construction tiles, 6 Intersection Markers (traffic signals), 4 Detour Marker signs shaped like an orange diamond with black arrows pointing in different direction on the face, 4 Road Closed Marker signs shaped like a rectangle with alternating black and yellow stripes, 13 Safe Passage tiles 41 colored white, 4 neutral City Markers having white circular stacks, 104 cards in all in the deck marked FRUSTRUCTION, 37 and 32 cards in the another deck 39 marked with the names of the 32 preselected cities.
In use each of the four players choose a respective different color. The Detour Marker signs, Road Closed Marker signs, neutral City Markers and Safe Passage white tile 41 (one subset of the tiles 31 ) are placed on the flat surface of board 1 in their respective places. The city deck of cards 39 is shuffled and 4 cards are dealt face up one for each of four players. These four cities represent the cities the roads are to be constructed to connect. The remainder of the city deck of cards is placed face down on the game board 1 . Players then place their City Markers 27 on the four cities dealt and return the cards to the bottom of the city deck of cards 39 . The other deck of cards 37 (see FIG. 1) is shuffled and dealt with 3 cards face down to each player such that each player is limited to only seeing the cards dealt to that player. The remainder of the cards in deck 37 is divided into two piles and placed face down on the board. The youngest player goes first with others following in clockwise order.
After drawing a card from the deck 37 , a player plays one of the four cards they hold. For example, if you hold a card marked “Play Immediately” this card must be played and followed, otherwise it is the card of your choice. If you hold more than one “Play Immediately” card, play the one of your choice and then the second “Play Immediately” card on your next turn. Once the card is played and instructions followed your turn is over.
The Frustruction deck of cards contains cards with a variety of cards with different indicia on their face side. One is the Mileage Card. When using this card a ratio of one road construction tile for 100 miles on the map 3 , a corresponding number of these tiles are place on the road space of the game board map. If you choose, you may connect your road construction tiles to cities or tiles of other players already on the game board in order to connect to your cities. Road construction tiles may not be placed on a space indicated as a city space.
Another card in the deck 37 has indicia indicating Remove Mileage Card. If this card is selected, the player can remove the corresponding number of road construction tiles from any road space on the game board, e.g., 1 tile=100 miles. You many not remove a safe passage tile from the game board once they are played.
The Intersection Card is also in the deck 37 . When selected a player may place this card on any vacant City space only. An Intersection or City Marker must be on a City space in order for the road construction tiles to be connected through that city. Only 6 intersections may be placed on the game board at any one time.
A Remove An Intersection Card is also in the card deck 37 . When selected the player may remove the Intersection Card of their choice from the game board.
The Detour Card is in deck 37 . This card detours traffic and is represented by the detour marker 33 . When this card is selected, the marker is placed on the game board on any road space. Detours may not be placed on top of road tiles. Road construction tiles are not connected as long as the Detour remains on that road between the road tiles. The Detour marker must be removed and a road construction tile put on the road for the tiles to be connected. Only 4 Detours may be placed on the game board at any one time. Detours may not be placed on a City space. There is a Remove a Detour Card in deck 37 which allows the selector player to remove any Detour of their choice from the game board.
Another card in deck 37 is the Road Closed Card. The Road Closed card allows the selector to place a Road Closed Marker 25 on any road space on the game board. Road Closed signs may not be placed on the top of road tiles. Once placed on the board the Road Closed Marker 25 remains until the game is over.
Still another card in deck 37 is the Safe Passage Card. This selected card is represented by a white tile 41 . This tile may be placed on any road space where there is not a road tile. Safe Passage tiles 41 may not be placed on a City space. Safe Passage tiles cannot be removed by other players and count the same as road construction tiles. Safe passage tiles may be used by any players during the game as with regular road tiles. Safe Passage tile must connect to one another when played. If all of the Safe Passage tiles 41 indicated on the card drawn cannot be used during that turn they are forfeited.
When the Exchange a City Card is drawn from deck 37 , a player will switch 2City Markers as instructed on the card drawn. If a Move a City Card is selected from the same deck, the player will move a City maker to a vacant city as instructed on the card drawn. Cities occupied by an Intersection are consider vacant for this purpose.
The Add a City Card is also in deck 37 . When selected a player must add another city to connect to (insert the colored peg into a Neutral City marker and place on the board). This player now has has an additional city to connect to through the game. If the city drawn is currently occupied by another player simply drawn another City card from deck 39 and resume play.
The Give a City Card in deck 37 , when drawn, allows the player to add another city to any opponent he or she chooses (i.e., insert the colored City peg 29 into a Neutral City marker and place on the board). That selected opponent player now has an additional city to connect to throughout the game.
The Double Play Card in the Frustruction deck of cards 37 allows the player to draw an additional card and do what is indicated on the card twice. If it is not possible to complete all of the instructions on the card drawn, the player completes what is possible and play moves to the next player. For example, if the card instructs you to place 2 Detour Markers and only one such marker is left to place.
In order to win a player must be the first to connect all of your City Markers. If two or more players connect all of their cities at the same time, clear the board. Each player that “tied” remains in the game. The cards in deck 37 are reshuffled and dealt three to each remaining player. The players left are each dealt two City cards from the top of the City Card deck 39 to connect and play resume as usual until there is a winner.
The present game teaches Geography, Topography, Strategy, Advance Planning, and dealing with sudden and unexpected adversity that can impact carefully planned logistics and strategy. If desired magnets can be used to hold the markers to the game board when traveling or semi-precious jewels with precious metals could also be used for the markers. The game board could be made of any appropriate material such as durable cardboard, paper or plastic.
Although the preferred embodiment of the present invention and the method of using the same has been described in the foregoing specification with considerable details, it is to be understood that modifications may be made to the invention which do not exceed the scope of the appended claims and modified forms of the present invention done by others skilled in the art to which the invention pertains will be considered infringements of this invention when those modified forms fall within the claimed scope of this invention. | A game that has a map of the contiguous U.S. with the players trying to construct roads at random locations between cities. Four cities on the map are selected at random, the first to construct roads between the cities wins the game using selected cards and overcoming other obstacles. | 0 |
[0001] This application is a continuation in part application based on application Ser. No. 10/114,070 filed on Apr. 3, 2002, which claims priority under 35 USC 119(e) from provisional patent application 60/347,889 filed on Jan. 15, 2002.
FIELD OF THE INVENTION
[0002] The present invention is directed to an improved animal feeds and mineral supplements, and particularly ones containing effective amounts of sulfur and garlic for insect repellency.
BACKGROUND ART
[0003] In the prior art, it is well know to provide mineral supplements to ruminant animals. One reason for this is that minerals are important in antler development, and an animal's diet does not always supply the necessary minerals for optimum antler growth.
[0004] As such, it is common for many hunters and landowners to establish mineral licks on their property, providing that such are permitted by law.
[0005] Besides antler growth, studies have shown that mineral supplementation increases forage uptake, improves forage digestion, and increases reproductive success.
[0006] An example of a mineral supplement is shown in U.S. Pat. No. 6,244,217 to Robbins, herein incorporated in its entirety by reference.
[0007] While mineral supplements provide significant improvements in the health of ruminant animals, insects continue to be a problem for animal health. Internal and external parasites have plagued deer and cattle for centuries. These pests reduce weight gain, and increase stress for the animals.
[0008] Accordingly, there is a need to provide improved insect repellents for use on ruminant animals.
[0009] The present invention solves this need by providing an insect repelling mineral supplement and/or feed that contains effective amounts of garlic and sulfur.
[0010] While it is know to use garlic powder as a feed additive for livestock, U.S. Pat. No. 5,268,357 to Yabiki et al., there is no suggestion of its use in mineral supplements for insect repellency. Yabiki et al. also do not teach the use of garlic and sulfur as part of a feed.
[0011] The Robbins patent discloses a mineral supplement that suggests that sulfur be present. However, Robbins does not exemplify a mineral supplement with sulfur, the nutrient lists do not show any sulfur. At most, the sulfur in the Robbins supplement would be in amounts to supply the needs of the animal's for health and nutrition, similar to an RDA in vitamins, e.g., generally a trace amount compared to the other main constituents of the supplement (a micro mineral as compared to a macro mineral). However, this patent does not identify amounts, nor suggest that the sulfur be in amounts for insect repellency.
[0012] Other feed supplements employ sulfur, see U.S. Pat. No. 3,794,740 to Achorn et al., but in the form of ammonium sulphate and levels of 0.33% by weight.
SUMMARY OF THE INVENTION
[0013] It is a first object of the present invention to provide an improved mineral supplement or animal feed for ruminant animals.
[0014] Another object of the invention is a mineral supplement or feed that provides insect repellency for animals in general, including dogs and cats.
[0015] One other object of the invention is a method of repelling insects from ruminant animals by modifying a mineral supplement or animal feed through the addition of effective amounts of garlic and sulfur.
[0016] Yet another object of the invention is using the effective amounts of garlic and sulfur in mineral supplements that double as animal attractants.
[0017] Other objects and advantages of the present invention will become apparent as a description thereof proceeds.
[0018] The invention entails improvements in mineral supplements, particularly mineral licks for deer. The improvement comprises having the mineral supplement contain an effective amount of garlic and sulfur for insect repellency. The mineral supplement mineral supplement can be either solid, liquid, or powder, and when in solid form, is preferably in the form of a mineral lick. It is preferred that the mineral supplement contains at least about 25% by weight of salt content, and more preferably a majority of salt.
[0019] The invention also entails a method of repelling insects for ruminant animals by adding an effective amount of garlic and sulfur to a ruminant animal mineral supplement; and placing the mineral supplement in one or more locations that are accessible by the ruminant animals. The mineral supplement as the solid, liquid, or granular and is preferably placed in the wild location such as a forest, or the like.
[0020] It is preferred that the garlic and sulfur amounts are at least 0.1% garlic and 0.5% sulfur on a weight basis of the supplement. The sulfur percentage is based on elemental sulfur, so that the amount of compounds containing other elements than sulfur may exceed the 0.5% elemental sulfur target. The garlic could range from at least 0.1% to up to 5%, more preferably up to 2.0% or 3.0%, and the sulfur could range from 0.5% to up to 10%, if desired. It should be understood that the upper limits of the sulfur and garlic relate more to the attractive and/or health effect of the mineral supplement, too much sulfur or garlic may actually repel deer from using the supplement. Too much sulfur may also be harmful to an animal.
[0021] Another aspect of the invention is the use of effective amounts of the garlic and sulfur in an animal feed for insect repellency. Typically, smaller or reduced amounts of the sulfur and garlic are used when made part of an animal feed since the animal's intake of the feed is generally much greater in weight percentage than that consumed when ingesting a supplement.
[0022] Another aspect of the invention is the use of effective amounts of the garlic and sulfur in a mineral supplement/animal attractant for animals, particularly deer. Examples of these attractants include those that use sodium carbonate (soda ash) as a major component, or other attractants such as corn and molasses licks, and various powder or solid attractants.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0023] The present invention offers significant improvements in the treatment of animals, particularly ruminant animals.
[0024] It is believed that the use of garlic as a component of the mineral supplement or animal feed helps repel insects as the animals sweat the garlic that has been ingested. Garlic also helps the animal's heart while at the same time reducing cholesterol.
[0025] The presence of sulfur is also advantageous in that it has medicinal properties and repels insects and snakes. When ingested, the sulfur will repel insects when it is sweated out by the animals.
[0026] The amount of garlic and sulfur is deemed to be an effective amount to function in its intended role as an insect repellent when sweated out of an animal. The effective amount may vary depending on the animal, and its size. The amount should be sufficient so that the garlic and sulfur leave the animal via sweat for insect repellency. It is believed that at least 0.10% garlic of the supplement on a weight basis should be sufficient for most animals. A preferred range of garlic would be up to 5.0%. More preferred ranges for garlic on a weight basis would be 0.1-5.0%, with an even more preferred range of 0.5 to 2.0 or 3.0%, and a target of around 0.8 to 1.20% or around 1.0%.
[0027] Similarly, at least about 0.5% sulfur should be used, with a preferred target being about at least 1% and up to about 10%. More preferred ranges for sulfur on a weight basis would be 0.5-6.0%, with an even more preferred range of 2.0-4.0%, and a target of around 2.5 to 3.5%, or around 3.0%.
[0028] The garlic can be added to the supplement in any known form. The form of garlic may depend on the form of the mineral supplement. Typically, supplements come in liquid, granular, and solid form, and the form of garlic would be chosen depending on the form of the supplement. It is preferred to use garlic powder or granules since this is an economical form of garlic. However, garlic oil could also be employed. In fact, garlic substitutes could be used as well. Aquaresins and oleoresins could also be used as a garlic source.
[0029] Likewise, the form of sulfur would also be related to the form of the supplement. In addition, the sulfur could be added in its pure form, or as a compound, e.g., sulfates, sulfides, and the like. As with garlic, it is preferred to add sulfur powder due to its cost and ease in making the final mineral supplement product.
[0030] The inventive mineral supplement is distinguished from known feed supplements in that feed supplements supply all the nutrition that the animal requires. In contrast, mineral supplements are akin to the vitamins people take on daily basis. To supply all of the nutritional requirements, feeds often employ proteins, carbohydrates, fiber, molasses, or other components that are typically found in feeds. The aim of the supplement aspect of the invention is not to feed the ruminant animals but provide an insect repellent as part of a mineral supplement. In this mode of the invention, there is no need to employ a feed component, and in fact, the presence of such a component may attract undesirable animals and lessen the impact of the insect repellent on the target population of ruminant animals.
[0031] Another distinguishing characteristic of the inventive mineral supplement is the presence of salts. The salt amount is generally at least 25% on a weight basis, and these levels are not found in feeds. For example, some supplements have up to 95% salt with the balance being 5.0% of the remaining components. However, it is believed that about 25% or even a majority of salt is needed to overcome the taste of the minerals, which tend to be bitter. The salt used is that typically found in mineral supplements, e.g., sodium chloride, etc.
[0032] An exemplary supplement could be obtained by modifying a commercially available supplement such Persimmon Pit, which is distribute sold by Johnson Laboratories of Troy Ala. Typically, this type of a supplement (without the persimmon) would contain the following:
monocalcium phosphate calcium carbonate magnesium oxide potassium chloride calcium pantothenate choline chloride folic acid Vitamin A supplement Vitamin D 3 supplement Vitamin B 12 supplement Vitamin E supplement Riboflavin niacinamide thiamin HCL
[0047] The amounts of the various components can vary. While Persimmon Pit is shown as one example, other commercial mineral supplement formulations (deer, cattle or the like) could also be modified as well with effective amounts of garlic and sulfur for insect repellency.
[0048] In addition, other minerals or vitamins, e.g., sodium carbonate, selenium, could be added or removed as would be within the skill of the art.
[0049] The improved mineral supplement can be made using the conventional techniques used for making solid, powder or liquid supplements. Since these techniques are well know in the art, a further description is not deemed necessary for understanding of the invention.
[0050] The mineral supplement is believed to be useful for any ruminant animal, but is particularly attractive for use with deer, and even more so whitetail deer.
[0051] Once the mineral supplement is made, it can be placed in one or more locations that are accessible to the ruminant animals. When using it for deer, it is preferred to make the supplement in the form of a lick, and position the lick in a location where deer normally visit, e.g., the wild such as fields, forests, meadows, or the like. In another alternative, the supplement could be positioned in a hole to be accessed by the animals. Of course, it could be used in granular form and put in feeders or the like as well.
[0052] If used for other animals such as cattle, it could be provided in these forms or other forms that would be conducive to ingestion by cattle.
[0053] Another embodiment of the invention entails using the effective amounts of sulfur and garlic in an animal feed for insect repellency. While a feed may not be desirable when compared to a mineral supplement for attracting animals such as whitetail deer, a feed may be advantageous for other ruminant animals, or may be applicable where it may be desirable to put out feeds for deer, times of drought or the like when natural food sources may be scarce. When employing a feed, it is preferred to use a reduced amount of sulfur and garlic as compared to the amounts noted above for the mineral supplements. The reason for this is that animals consume more feed per day than supplements. For sulfur, a preferred range is believed to be up to around 1.0%, with a more preferred maximum of up to around 0.5%.
[0054] The amount of garlic is not as sensitive for animals as the amount of sulfur. Consequently, the same ranges and targets could be used for the feed as for the supplement. From an economic standpoint though, less garlic can be employed in the feed since, as noted above, the animal will consume more feed by weight than supplement. As such, the garlic can range up to only 3.0% rather than 5.0% as with the supplement. The following example shows why the amount of sulfur and garlic can be reduced in a feed. If the animal consumes 1.0 pounds a day of the supplement, this translates to 0.1 pounds of garlic at a 1.0% by weight garlic loading of the supplement. If the animal consume 5 pounds of feed a day, there only needs to be 0.2% by weight of garlic in the feed to ingest the same amount of garlic as the supplement for insect repellency. Similarly, 3.0% sulfur in the supplement can be reduced to 0.6% sulfur in the feed. Of course, these percentages can change depending on the expected consumption of supplement and feed.
[0055] It should be understood that an animal feed is different from a feed supplement or a mineral supplement. The Yabiki et al. patent, hereby incorporated by reference in its entirety, particularly its description of garlic powder, exemplifies the difference between feeds and feed additives, and teaches modifying a feed with bile powder, garlic powder, and other feed additives for increasing disease resistance.
[0056] The intended animal feed of the invention is one that is distinguished from mineral or feed supplements. Feeds may come in different forms, e.g., roughage, cereals, etc. Roughages mostly likely have a high crude fiber content and low digestible energy content. In contrast, cereals have readily available carbohydrates, sugars, starches, fats and oils, which are more digestible and contain less fiber than roughage-type feeds. With feed, the focus is providing sufficient energy and protein to the animal. In contrast, supplements, whether they are for energy, vitamins, proteins, or minerals, are high in concentration of the material(s) identified as the supplement. Energy supplements can be cereal by-products. Protein supplements, such as soybean or canola meal typically have more than 20% protein. Mineral supplements can concentrate on providing macro minerals such as calcium, phosphorus, sodium, chlorine and potassium, or micro-minerals such as iron, copper, sulfur, zinc, manganese, cobalt, iodine, selenium, molybdenum and chromium.
[0057] According to one aspect of the invention, the garlic and sulfur are used in a mineral supplement, particularly for deer. In another aspect, the garlic and sulfur are used in an animal feed, preferably a ruminant animal feed, wherein the primary components are energy and/or protein providers such as hay, alfalfa, grasses, clover, trefoil, haylage, green chop, corn silage, straw, corn stover, corn, wheat, oats, barley, soybeans. These components generally constitute a majority of the feed in terms of weight percent.
[0058] The components found in a typical feed composition are as follows: corn chops; soybean meal; dehydrated alfalfa meal, wheat middlings; cane molasses; defluorinated phosphate; calcium carbonate; salt; vitamin A supplement; vitamin d-3 supplement; vitamin E supplement; niacin; choline chloride; D-pantothenic acid; riboflavin supplement, zinc oxide, copper sulfate, zinc sulfate; manganese sulfate; ferrous carbonate; ethylene diamine dihydriodide; magnesium oxide; cobalt carbonate; sodium selenite; and natural and artificial flavorings. It should be understood that this is just one example of an animal feed, and other known feeds can be used as part of the invention. The percentages of the various components may vary, but this variance may occur without altering the basic aspect of the invention.
[0059] When using the garlic- and sulfur-containing feed, the feed is fed to the animals using a normal feeding schedule, such feeding resulting in improved repellency to insects, and better animal health.
[0060] It should also be understood that when using sulfur in compound form, the sulfur is the major component of the compound. Adding zinc as a desired micro mineral using zinc sulfate would not supply the necessary amount of sulfur for insect repellency.
[0061] As noted with the mineral supplements, the animal feed is primarily intended for ruminant animals such as cattle, deer, elk, and the like. However, it is believed that the invention of the combination of effective amounts of garlic and sulfur for insect repellency can have use in feeds for other animals, particularly dogs and cats, and chickens. Again, this type of a feed would the type that would supply the daily nutritional needs to the animal, just as present day dog and cat food and chicken feed do.
[0062] The mineral supplement aspect of the invention can doubles as an animal attractant. These attractants contain mineral supplements and also are presently being used to attract deer or the like. Examples of known mineral supplements/attractants include Deer-Go-Insane, which is made by Johnson Laboratories, Inc. of Troy, Ala. This attractant uses sodium carbonate (soda ash) as the primary attractant and it is available as a powder and liquid. Other ones that can be purchased are Deer Dynomite, available through the Internet, and Evolved Habitat products, also available on the Internet, see for example, www.scorpionoutdoors.com. Of course, other powdered, solid, or liquid attractants using various compounds to lure deer could include the effective amounts of sulfur and garlic for combined luring, insect repellency, and improved animal health. Attractants may also be pure attractants that do not contain minerals for supplementation. One attractant of this type would be a mix of corn and molasses, preferably in block form, or merely molasses in liquid form. It is believed that any attractant available today that could support inclusion of the garlic and sulfur would be adaptable for the invention. Certain attractants are distinguishable from the mineral supplements in that these types do not contain minerals in such levels that would supplement the deer's mineral intake. Other animal attractants are also distinguishable from feed in that they generally do not include feed components in sufficient quantities that a deer or other animal would eat the attractant for daily nourishment.
[0063] When using the garlic and sulfur in these types of animal attractants, the amounts to be used parallel those used in the mineral supplements described above. The need to use less of the garlic and sulfur as is described above for feeds does not apply to the animal attractants since the attractants are not consumed by the animals in the same way that typical feeds are consumed.
[0064] As such, an invention has been disclosed in terms of preferred embodiments thereof, which fulfills each and every one of the objects of the present invention as set forth above and provides a new and improved mineral supplement, attractant and feed for animals.
[0065] Of course, various changes, modifications and alterations from the teachings of the present invention may be contemplated by those skilled in the art without departing from the intended spirit and scope thereof. It is intended that the present invention only be limited by the terms of the appended claims. | A feed or mineral supplement for animals, especially deer, contains effective amounts of sulfur and garlic to repel insects from the animals. By inducing the insect repellent into the animal via ingestion of the attractant, disease and stress in the animals as caused by the insects is reduced. A feed is easily modified by adding the effective amounts of the garlic and sulfur to the feed. | 8 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is the U.S. National Stage of International Application No. PCT/EP2011/067367 filed Oct. 5, 2011 and claims benefit thereof, the entire content of which is hereby incorporated herein by reference. The International Application claims priority to the European application No. 10187251.3 EP filed Oct. 12, 2010, the entire contents of which is hereby incorporated herein by reference.
FIELD OF INVENTION
[0002] The invention relates in general to a self-centering clamping device and a measuring device for a blade. The invention relates particularly to a self-centering clamping device and a measuring device with a blade of a turbine, engine or compressor.
BACKGROUND OF INVENTION
[0003] In the measurement of moments or geometric measurements, it is important to fix and center the measurement objects exactly for the purpose of exact measurement. The measurement objects must be capable of being positioned quickly and reliably in a reproducible way.
[0004] Conventionally, blades, such as turbine, engine or compressor blades, are fixed in a grooved block with bracing by an eccentric. Damage to the blade may occur during bracing.
[0005] GB 2 047 897 shows a device for the measurement of turbine blades, with a groove for receiving the blade in a transverse direction of the blade and with a bracing mechanism for bracing the blade in a longitudinal direction of the blade.
[0006] U.S. Pat. No. 5,792,267 discloses a fastening device for a turbine blade for the purpose of coating the blade, with a cylindrical base block, with a groove receiving the root and with a push-on sleeve and a cover for the block in order thereby to secure the blade.
SUMMARY OF INVENTION
[0007] The object of the invention is to improve the fixing of blades.
[0008] This object is achieved by the features of the independent claim(s).
[0009] According to a first aspect of the invention, a self-centering clamping device for a blade comprises a mount with a root reception orifice which has a contour adapted to a root of the blade. The root reception orifice extends in the vertical direction and has a vertically running groove for receiving at least part of the root of the blade, and a rotatable roller is arranged in a lower region of the root reception orifice and forms a stop for the root of the blade, a contact region of the roller for the root lying in an angular range larger than 0° and smaller than 90°, and the angular range being oriented upward and into the root reception orifice.
[0010] When the blade is inserted into the reception orifice, the blade is moved by gravity onto the roller functioning as a stop and is thus centered automatically. Reliable positioning without bracing is thus possible. On account of the movability of the roller, wear caused by friction is prevented. Damage to the blade is likewise avoided. The reception orifice is adapted essentially to the set-up of a turbine or compressor wheel disk, thus making it easier to position the blade. The arrangement of the roller make it possible to apply the blade in that quadrant of the roller which assists a downward movement of the blade by rotation. The blade thus slides with low friction into the reception orifice.
[0011] The roller may have, in particular, a rolling bearing. By means of a rolling bearing, for example in the form of a ball, barrel or needle bearing, friction is reduced and reliability and precision are increased. However, plane bearings may basically also be considered as bearings for the roller.
[0012] An axis of rotation of the roller may be at an angle with respect to the horizontal. By means of an inclined roller, the centering of the blade can be further improved, since the blade, as it were, may slip along the inclined circumferential surface of the roller into the reception orifice.
[0013] The mount ( 5 ) may be a grooved block, thus making handling easy.
[0014] The roller may be arranged opposite a vertically running groove orifice. As a result of the arrangement of the roller, the blade is pressed into the groove and is thereby fixed securely.
[0015] A sliding roller may be arranged above the roller and opposite the groove orifice. The sliding roller makes it possible for the blade to be introduced into and removed from the reception orifice without any friction. In this case, in particular, a plurality of sliding rollers may also be arranged one above the other. This reduces the risk that the blade tilts and also, with regard to larger blades, makes it possible to handle the blade in the reception orifice in a simple way. Instead of the sliding roller or sliding rollers, a sliding surface made from a material having low friction may also be present.
[0016] Two rollers may be provided. The distribution of the weight of the blade to two rollers makes it possible to have an even more reliable clamping device. The two rollers may be inclined with respect to one another in such a way that a type of funnel is obtained for the blade.
[0017] Although not necessary, an eccentric for clamping the root may be arranged opposite the groove orifice. In addition, an eccentric may fix the blade if, for example, the clamping device has to be moved together with the inserted blade for the purpose of the workstep.
[0018] The root reception orifice may be in the form of a blade fastening groove, thus making handling easier.
[0019] According to a second aspect of the invention, a measuring device for a blade comprises a self-centering clamping device, as described above. The measuring device likewise has the abovementioned advantages and designs. By means of the measuring device, for example, the blade can be positioned reliably and reproducibly on a moment balance or a measuring apparatus.
BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The invention is described in more detail below by means of the drawings.
[0021] FIG. 1 shows a perspective illustration of a measuring device with self-centering clamping device according to the invention.
[0022] FIG. 2 shows a sectional illustration of the measuring device and of the self-centering clamping device in a side view according to the invention.
[0023] FIG. 3 shows a sectional illustration of the measuring device and of the self-centering clamping device in a top view according to the invention.
[0024] FIG. 4 shows diagrammatically a contact region of the roller according to the invention.
DETAILED DESCRIPTION OF INVENTION
[0025] The drawings serve merely to explain the invention and do not restrict this. The drawings and the individual parts are not necessarily true to scale. Identical reference symbols designate identical or similar parts.
[0026] FIG. 1 shows a measuring device 1 with a clamping device 2 for a measurement object, such as, for example, a turbine blade or a compressor blade 3 (referred to below as “blade”). The clamping device 2 comprises a baseplate 4 . By means of the baseplate 4 , the measuring device 1 is fastened to a moment balance, not illustrated, or to an intermediate structure for measuring the blade 3 .
[0027] A mount 5 is fastened essentially vertically on the baseplate 4 . Formed in the mount 5 is a reception orifice 6 in which a blade root 7 of the blade 3 is fastened. The mount 5 and reception orifice 6 may be designed, for example, as a grooved block. A plurality of sliding rollers 8 are arranged in the reception orifice 6 and make it easy to insert the blade 3 into the clamping device 2 . By means of an inclined roller 9 , the blade root 7 of the blade 3 is positioned securely and reproducibly in the reception orifice 6 .
[0028] FIG. 2 shows a sectional illustration of the measuring device 1 with the roller 9 serving as a stop. Three sliding rollers 8 are arranged vertically one above the other in the mount 5 .
[0029] Part of the sliding rollers 8 projects into the reception orifice 6 , specifically at a base region of the groove-shaped reception orifice 6 , that is to say opposite a vertically running groove orifice. The sliding rollers 8 consequently assist the insertion and removal of the blade 3 .
[0030] Further sliding rollers 8 may be arranged at the two lateral regions of the reception orifice 6 . Two or only one sliding roller 8 may also be provided.
[0031] Arranged in the lower region of the reception orifice 6 , underneath the sliding rollers 8 , is the roller 9 on which part of the blade root 7 of the blade 3 lies and which consequently serves as a movable stop.
[0032] The roller 9 is mounted rotatably about an axis of rotation 10 . The roller 9 may be designed, for example, as a rolling bearing with an inner fixed inner ring or inner core, with an outer rotatable roller and with rolling bodies, such as, for example, rollers or balls, arranged between them.
[0033] Instead of a roller, a cylinder, ball or similar body which enables the blade 3 to roll may also be used as a stop for the blade 3 . Not the entire circumferential surface is needed for the functions of a stop, and therefore a body which has only part of the circumferential surface of, for example, a roller, cylinder or ball may also be used as a stop.
[0034] With regard to the blade roots 7 shown in the exemplary embodiment, the end faces 12 do not run at right angles (90°) to the side faces 13 , but instead at an angle which may lie between 30° and 90°. In the present exemplary embodiment, therefore, the axis of rotation 10 of the roller 9 is at an angle with respect to the horizontal. The axis of rotation 10 of the roller 9 is consequently not parallel to the axes of rotation of the sliding rollers 8 . Instead, the axis of rotation 10 is oriented parallel to the end face 12 of the blade root 7 . If the end faces 12 run at right angles (90°) to the side faces 13 , it is advantageous if, instead of one roller 9 , two rollers are present, the axes of rotation of which run, in particular, in a v-shaped manner with respect to one another.
[0035] The roller 9 is arranged with respect to the reception orifice 6 in such a way that a contact region 11 of the roller 9 for the blade root 7 lies in an angular range larger than 0° to smaller than 90°, in particular 30° to 60°, for example at an angle of about 45°, to the circumferential surface of the roller 9 (cf. FIG. 4 ). In this case, the angular range is measured from the horizontal upward, so that the angular range is oriented upward and toward the reception orifice 6 . This ensures that the root 7 does not engage either tangentially, that is to say at a virtual interface of a horizontal with the outer face of the roller 9 , or directly radially, that is to say at a virtual interface of a vertical with the outer face of the roller 9 . The horizontal and vertical in this case run through the center point of the roller 9 .
[0036] With tangential bearing contact, there is the risk that the blade root 7 could move past the roller 9 , while, in the case of directly radial perpendicular contact, the rolling properties of the roller 9 are not brought to bear. Since the blade root 7 impinges in the region between these two end points, the blade root 7 and as it were roll automatically into the end position on account of its weight by means of the roller 9 .
[0037] The roller 9 or part of the roller 9 may be elastically deformable in order to make it possible to adapt the roller 9 to the blade root 7 . The width of the roller 9 may be dimensioned according to the conditions of the blade 3 , although the roller 9 should have a minimum width which keeps the pressure load for the blade 3 and for the roller 9 within tolerable limits. The diameter of the roller 9 and its orientation should be dimensioned in such a way that impingement of the blade 3 in the correct circumferential region and subsequent rolling are possible.
[0038] Alternatively, two rollers may be provided, which are then advantageously inclined with respect to one another and form a funnel or V-shaped stop into which the blade root 7 can slide.
[0039] An optional eccentric for clamping the blade root 7 may be arranged opposite the vertically running groove orifice, that is to say in the region of the sliding rollers 8 . For example, the middle of the three sliding rollers 8 will be replaced by an eccentric which can additionally brace the blade 3 , for example for transport purposes.
[0040] FIG. 3 shows the measuring device 1 in a sectional illustration in a top view. The baseplate 4 can be fastened to a moment balance by means of screws, pins, bolts or similar fastening means. The reception orifice 6 formed in the mount 5 is adapted in its contour to the blade root 7 of the blade 3 in order to ensure secure fixing of the blade 3 . In particular, side regions of the reception orifice 6 taper conically so as to be adapted to the blade root 7 .
[0041] The reception orifice 6 may contain a groove or be designed as a groove, in particular it can be adapted to a blade fastening groove into which the blade 3 is finally mounted. The sliding rollers 8 and the roller 9 are arranged in a rearward part or base region of the reception orifice 6 , said rearward part or base region being arranged opposite a vertically running groove orifice.
[0042] The measuring device 1 is used as described below: first, the measuring device 1 is fastened to a moment balance or a similar measuring instrument. The blade root 7 of the blade 3 is subsequently introduced into the reception orifice 6 of the clamping device 2 until the blade root 7 comes to bear on the roller 9 . In this case, the sliding rollers 8 assist frictional movement of the blade root 7 in the reception orifice 6 . The blade 3 is self-centered by means of the roller 9 . As a result of gravity, the blade 3 slides through the reception orifice 6 until it is fixed to the roller 9 .
[0043] After measurement has taken place, the blade 3 is drawn out of the reception orifice 6 and is in this case assisted again by the sliding rollers 8 . | A self-centering clamping device for a blade includes a mount having a root reception orifice which has a contour adapted to a root of the blade. The root reception orifice extends in the vertical direction and has a vertically running groove for receiving at least part of the root of the blade. A rotatable roller is arranged in a lower region of the root reception orifice and forms a stop for the root of the blade, a contact region of the roller for the root lying in an angular range larger than 0° and smaller than 90°, and the angular range being oriented upward and into the root reception orifice. | 5 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to, and the benefit of, U.S. Provisional Patent Application Ser. No. 61,469,008 filed Mar. 29, 2011, the entire contents of which are incorporated by reference herein.
BACKGROUND
[0002] 1. Technical Field
[0003] The present disclosure relates generally to a surgical device for use in a minimally invasive surgical procedure. More particularly, the present disclosure relates to a surgical portal device adapted and configured to receive surgical instruments therein, and to reposition the distal ends of the surgical instruments that are placed through the surgical portal device.
[0004] 2. Description of Related Art
[0005] Increasingly, many surgical procedures are performed through small incisions in the skin. As compared to the larger incisions typically required in traditional procedures, smaller incisions result in less trauma to the patient. By reducing the trauma to the patient, the time required for recovery is also reduced. Generally, the surgical procedures that are performed through small incisions in the skin are referred to as endoscopic. If the procedure is performed on the patient's abdomen, the procedure is referred to as laparoscopic. Throughout the present disclosure, the term minimally invasive is to be understood as encompassing both endoscopic and laparoscopic procedures.
[0006] During a typical minimally invasive procedure, surgical objects, such as surgical access devices (e.g., trocar and cannula assemblies) or endoscopes, are inserted into the patient's body through the incision in tissue. In general, prior to the introduction of the surgical object into the patient's body, insufflation gas is used to enlarge the area surrounding the target surgical site to create a larger, more accessible work area. Accordingly, the maintenance of a substantially fluid-tight seal is desirable so as to inhibit the escape of the insufflation gases and the deflation or collapse of the enlarged surgical site. In response to this, various access devices with sealing features are used during the course of minimally invasive procedures to provide an access for surgical objects to enter the patient's body. Each of these devices is configured for use through a single incision or a naturally occurring orifice (i.e. mouth, anus, or vagina) while allowing multiple instruments to be inserted through the device to access the working space beyond the device, generally an internal body cavity.
[0007] During procedures employing multiple surgical instruments through a single incision access device, it is advantageous to determine the position of the end effectors relative to each other and/or relative to a fixed reference point. This is desirable when one or more of the instruments includes an end effector that is articulable relative to the surgical instrument. Identifying the position of each end effector relative to the other end effectors and/or a common reference point is advantageous during a surgical procedure.
[0008] Some disadvantages of minimally invasive procedures include a lack of direct visualization of the surgical site and reduced dexterity of instruments, as compared to traditional open surgeries.
[0009] One surgical technique used to increase the ability of the surgeon to visualize and access critical anatomy is triangulation. Triangulation is a principle in which the positioning of the surgical instruments may be determined by having known initial positions of the instruments with respect to a given point, e.g., another device or instrument, and tracking the change in position from that initial position. One method of triangulation involves holding surgical instruments so that their tips form the apex of an imaginary triangle. By knowing the initial positions of surgical instruments with respect to a given point and by tracking the change in position, the coordinates of the surgical instruments are determinable.
[0010] One example, as disclosed by US Patent Application Pre-Grant Publication US2005/0234294, uses an articulating element disposed near a distal region and pivotally coupled to hinges by linkages.
[0011] Another example, as disclosed by US Patent Application Pre-Grant Publications US2007/0167680 and US2008/0051631, uses a rod connected to linking members which spread a set of arm members containing surgical devices apart when the rod is actuated.
[0012] Another example, as disclosed by US Patent Application Pre-Grant Publication US2008/0188868, uses a collar, a wedge, a balloon or bands to help maintain a divergence between the surgical devices.
[0013] Yet another example, as disclosed by U.S. Pat. Nos. 5,318,013; 5,395,367; and 5,511,564, uses an actuator including an articulated linking comprising a pair of arms pivotably connected to a push rod and to shafts of respective grasping forceps to enable relative spreading of the grasping forceps from a straightened or mutually parallel configuration to a spread use configuration.
[0014] In conventional minimally invasive surgical procedures, triangulation is achieved through insertion of multiple instruments through multiple openings. In most minimally invasive surgical procedures through a single incision, straight and rigid surgical instruments are inserted through a single incision. To control the instruments, a surgeon often crosses his hands. The lack of triangulation makes visualization and access of critical anatomy potentially difficult.
[0015] Furthermore, the placement of multiple instruments through a single incision increases the potential of interference among those instruments. It would be advantageous to space those instruments apart within the surgical site, without necessitating a larger incision.
[0016] Consequently, a continuing need exists for improved minimally invasive surgical devices.
SUMMARY
[0017] The present disclosure relates to surgical access ports for use in minimally invasive procedures where articulation of instruments disposed in a body cavity is required to reach off-axis points within the body cavity and determine the relative positioning of end effectors of surgical instruments disposed through the surgical access ports.
[0018] According to one embodiment of the present invention, a surgical access port is provided which includes a housing, at least two lumens extending through the housing, and an articulation structure disposed in the surgical access port. The housing is comprised of a cylindrical member having proximal and distal ends, and defining a longitudinal axis. Each lumen has an entrance aperture in the proximal end of the housing, and an exit aperture in the distal end of the housing. The body of the lumen gradually widens toward the distal end of the housing to accommodate the radial movement of surgical instruments under articulation control.
[0019] The articulation structure is envisioned to have different configurations. In one configuration, the actuation member may be a worm gear, with the rotating members abutting the actuation member as gear wheels. In this configuration, the actuation member is restricted from linear translation along the longitudinal axis.
[0020] In another configuration, the actuation structure is a toothed rack abutting rotating pinions. In this configuration, the actuation structure is free to translate along the longitudinal axis.
[0021] Connecting the rotating members to the tubular members are rigid arms. The rigid arms are connected to the rotating members such that they rotate about an axis substantially transverse to the longitudinal axis when the actuation structure is engaged, i.e., they move radially with respect to a longitudinal axis of the device. This rotation of the rigid arms thus effects angular displacement of the tubular members, and any surgical instruments disposed therethrough, from the longitudinal axis.
[0022] In some configurations, more than two tubular members, more than one actuation member, and/or more than two rotating members may be present, allowing for triangulation of multiple instruments with respect to multiple axes. In such configurations, actuation members may be oriented such that they articulate surgical instruments in multiple axes. Additionally, the spacing between tubular members may not be symmetrical about the longitudinal axis, so as to achieve a desired triangulation within a body member.
[0023] A handle may extend proximally from the actuation member, through the housing and further proximally so that the handle may be engaged by an operator. This handle provides direct control of the articulation structure to the operator of the surgical access port.
[0024] Also disclosed is a method for achieving triangulation, wherein the surgical access port is placed within a body member, surgical instruments are disposed in the surgical access port, and the actuating member is engaged such that articulation of the surgical instruments in a body cavity is achieved, allowing for triangulation of the instruments to determine the relative positioning of the end effectors of the surgical instruments.
[0025] Further disclosed herein are the steps of performing a minimally invasive procedure through the surgical access port, removing the surgical instruments from the surgical access port, and removing the surgical access port from the body member following surgery.
[0026] The various aspects of this disclosure will be more readily understood from the following detailed description when read in conjunction with the appended drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Embodiments of the present disclosure are described herein with reference to the accompanying drawings, wherein:
[0028] FIG. 1 is a side perspective view of a surgical access port according to an embodiment of the present disclosure, disposed in an incision site (shown in cut-away view) and containing an articulation structure (shown in phantom view);
[0029] FIG. 2 is a side view of the surgical access port, with a cylindrical member (shown in phantom view), and the articulation structure comprising two lumens, two tubular members, two rigid arms, and two gear wheels abutting a worm gear;
[0030] FIG. 3 is a top plan view of the surgical access port shown in FIG. 2 , with the articulation structure shown in phantom view.
[0031] FIG. 3A is a partial detail view of the area surrounding a lumen, tubular member, and rigid arm in FIG. 3 ;
[0032] FIG. 4 is a bottom plan view of the surgical access port shown in FIG. 2 , with the articulation structure shown in phantom view and showing shaped lumen exits at the distal end of the cylindrical member;
[0033] FIG. 5 is a side view of the surgical access port as shown in FIG. 2 , disposed in a layer of tissue (shown in cut-away view) and with two surgical instruments inserted through the lumens;
[0034] FIG. 6 is a side view of the surgical access port as shown in FIG. 5 , with the articulation structure having been engaged and the tubular members and surgical instruments disposed at an angle with the longitudinal axis;
[0035] FIG. 7 is a side view of an embodiment of a surgical access port (shown in phantom view), wherein more than two lumens and corresponding gear wheels and surgical instruments are present in an articulation structure;
[0036] FIG. 8 is a side view of an embodiment of a surgical access port (shown in phantom view), wherein the articulation structure comprises a toothed rack abutting rotating pinions; and
[0037] FIG. 9 is a side view of the surgical access port shown in FIG. 8 , with the actuation structure having been engaged and the tubular members and surgical instruments disposed at an angle with the longitudinal axis.
DETAILED DESCRIPTION OF EMBODIMENTS
[0038] Embodiments of the presently disclosed surgical access ports for use in minimally invasive surgery are described in detail with reference to the drawings, in which like reference numerals designate identical or corresponding elements in each of the several views. As used herein, the term “distal” refers to that portion of the tool, or component thereof which is further from the user while the term “proximal” refers to that portion of the tool or component thereof which is closer to the user. The presently disclosed surgical access ports are usable in an incision through a patient's tissue or in a naturally occurring orifice (e.g. anus or vagina).
[0039] Referring initially to FIG. 1 , a surgical access port, generally designated as 100 , is shown. The surgical access port 100 is comprised of a cylindrical member 110 that has a generally hourglass profile. The cylindrical member 110 has a proximal end 110 a and a distal end 110 b and defines a longitudinal axis A 1 . Extending from the proximal end 110 a to the distal end 110 b of the cylindrical member 110 are two lumens 120 . Each lumen 120 has an entrance 120 a in the proximal end 110 a of the cylindrical member 110 , and an exit 120 b in the distal end 110 b of the cylindrical member 110 . The lumens 120 widen toward the distal end 110 b of the cylindrical member 110 to accommodate radial movement within the surgical access port 100 of objects under articulation control. The lumen exits 120 b are similarly elongated for this purpose.
[0040] Disposed within the cylindrical member 110 is an articulation structure 130 , which comprises two tubular members 140 disposed in the lumens 120 , two worm wheels 160 , and a worm gear 150 . Extending proximally of the worm gear 150 and above the proximal end 110 a of the cylindrical member 110 is a handle 180 .
[0041] Turning now to FIG. 2 , a side view of the surgical access port 100 is shown, with the cylindrical member 110 in phantom view and the articulation structure 130 shown in standard view. Looking to the articulation structure 130 , the worm gear 150 is configured to rotate about the longitudinal axis A 1 , but is restricted from axial translation along the longitudinal axis A 1 . The worm gear 150 abuts the worm wheels 160 , and helical thread 150 a is configured to engage the teeth 160 a of the worm wheels 160 . The worm wheels 160 are fixably attached to the rigid arms 170 by any suitable method, and may be integrally formed of the same member. The rigid arms 170 , in turn, are attached to the tubular members 140 . The attachment of the rigid arms 170 to the tubular members 140 is by way of an attachment to an outer surface of the tubular members 140 , and may be achieved by any suitable coupling method, such as adhesion or clamping. Extending proximally from the articulation structure 130 is a handle 180 . The handle 180 is operatively connected to the worm gear 150 , and is configured such that an operator of the surgical access port 100 may engage the articulation structure 130 by engaging the handle 180 . The handle 180 allows the operator of the surgical access port 100 to engage the articulation structure 130 from a point proximal of the cylindrical member 110 .
[0042] Referring to FIG. 3 , a top plan view of the surgical access port 100 is shown. The lumens 120 containing the tubular members 140 extend from a proximal end 110 a of the cylindrical member 110 . At a distal end 110 b ( FIG. 1 ) of the cylindrical member 110 , the exit aperture 120 b of the lumens 120 can be seen in phantom view. The lumens 120 and exit aperture 120 b of the lumens 120 widen towards the distal end 110 b of the cylindrical member 110 such that the tubular members 140 and rigid arms 170 are allowed freedom of movement along an axis substantially transverse to the longitudinal axis A 1 ( FIG. 1 ). When the worm wheels 160 (shown in phantom) are set in motion by the worm gear 150 , they cause the rigid arms 170 and tubular members 140 to rotate, and the tubular members move radially through the widened lumen 120 and lumen exit aperture 120 b.
[0043] FIG. 3A shows an enlarged detail view of the area encompassing lumen 120 , tubular member 140 , and rigid arm 170 from the top plan view of FIG. 3 . Tubular member 140 is shown disposed within the lumen 120 . Shown in phantom view is the widened lumen exit 120 b . Also shown in phantom view is the rigid arm 170 abutting the tubular member 140 .
[0044] Turning now to FIG. 4 , a bottom plan view of the surgical access port 100 is shown. In this view, the exit apertures 120 b of the lumens 120 are shown in the foreground. As in FIG. 3 , the rigid arms 170 are attached to the tubular members 140 . Upon engagement of the articulation member 150 ( FIG. 1 ), the tubular members 140 are displaced radially with respect to the longitudinal axis A 1 ( FIG. 1 ), and are allowed freedom of movement through the exit apertures 120 b of the lumens 120 . Thus, the end effectors 195 b ( FIG. 5 ) of the surgical instruments 195 ( FIG. 5 ) are placed at off-axis positions within an internal body cavity 190 b ( FIG. 5 ).
[0045] As seen in FIG. 5 , the surgical access port 100 is configured to be disposed in a layer of tissue 190 , often at an incision site 190 a . The proximal and distal ends 110 a and 110 b of the cylindrical member 110 may include rims or flanges to aid in anchoring the surgical access port 100 in the layer of tissue 190 . Also shown is a pair of surgical instruments 195 having end effectors 195 b , disposed in the tubular members 140 . The surgical access port 100 is oriented such that the articulation structure 130 is substantially parallel to the longitudinal axis A 1 and the surgical instruments 195 and end effectors 195 b are disposed in the tubular members 140 and exit within the internal body cavity 190 b.
[0046] In use, the operator of the surgical access port 100 engages the handle 180 and actuates the worm gear 150 . Engagement of the handle 180 transmits torque to the worm gear 150 , causing it to rotate about the longitudinal axis A 1 . The helical thread 150 a of the worm gear 150 engages the teeth 160 a of the worm wheels 160 , and causes them to rotate about an axis substantially transverse to the longitudinal axis A 1 . The rotational motion of the worm wheels 160 in turn causes the rigid arms 170 to which they are attached to pivot about the axis of rotation of the worm wheels 160 . As the rigid arms 170 are attached to the tubular members 140 and the surgical instruments 195 and end effectors 195 b are inserted therethrough, the pivoting of the rigid arms 170 causes radial displacement of the surgical instruments 195 and end effectors 195 b with respect to the longitudinal axis A 1 .
[0047] Turning now to FIG. 6 , the surgical access port 100 is shown with the articulation structure 130 having been engaged. The worm wheels 160 have rotated in response to the rotation of the worm gear 150 . The pivoting of rigid arms 170 thus cause tubular members 140 and the surgical instruments 195 disposed therethrough to deflect with respect to the longitudinal axis A 1 . This displacement is permitted by the gradually widened lumens 120 toward the distal end 110 b of the cylindrical member 110 and the lumen exit apertures 120 b . With worm gear 150 having been actuated a measured amount, and knowing the rate of rotation of the actuation structure 130 , the operator of the surgical access port 100 can determine the relative spacing of the end effectors 195 b of the surgical instruments 195 with respect to a known point, such as the cylindrical member 110 or the longitudinal axis A 1 .
[0048] Referring now to FIG. 7 , another embodiment of a surgical access port, designated 200 , is shown. The articulation structure 230 of surgical access port 200 is configured to triangulate more than two surgical instruments 195 , and includes at least a third surgical instrument 295 with end effector 295 b . Disposed in the surgical access port 200 is a third lumen 220 containing a third tubular member 240 , and a corresponding third worm wheel 260 and third rigid arm 270 . The third worm wheel 260 is oriented on an axis substantially transverse to the longitudinal axis A 1 , but also different from the axis along which the first and second worm wheels 160 are disposed. The surgical access port 200 is configured such that upon actuation of the worm gear 150 , the third worm wheel 260 will rotate about an axis substantially transverse to the longitudinal axis A 1 (but different from the axes about which first and second worm wheels 160 rotate), and third tubular member 240 and third surgical instrument 295 will articulate in conjunction with the first two tubular members 140 and first two surgical instruments 195 . As explained above, the operator of the surgical access port 200 can determine the relative spacing of the end effectors 195 b , 295 b of the surgical instruments 195 , 295 with respect to a known point, such as the cylindrical member 110 or the longitudinal axis A 1 .
[0049] Turning now to FIG. 8 , a surgical access port 300 is shown, which contains a toothed rack 350 as an actuation member. The toothed rack 350 is attached to a handle 180 extending proximally from the cylindrical member 110 . In use, the handle 180 is engaged by an operator at the proximal end 110 a of the cylindrical member 110 , force is transmitted to the toothed rack 350 . The toothed rack 350 translates along the longitudinal axis A 1 . As the toothed rack 350 moves distally along the longitudinal axis A 1 , the teeth 350 a of the toothed rack engage the teeth 360 a of pinions 360 and cause them to rotate about an axis substantially transverse to the longitudinal axis A 1 . The rigid arms 170 , attached to the pinions 360 , pivot about the axis about which the rotating members rotate, and cause the tubular members 140 to which they are connected to displace radially from the longitudinal axis A 1 .
[0050] Referring to FIG. 9 , the surgical access port 300 is shown in an actuated state, with the toothed rack 350 displaced distally along the longitudinal axis A 1 . The pinions 360 , rigid arms 170 , and tubular members 140 have all pivoted about axes transverse to the longitudinal axis A 1 , resulting in the surgical instruments 195 disposed therethrough to be displaced radially to a desired position within the internal body cavity 190 b . As in the previous embodiments, the known dimensions of the articulation structure 330 allows an operator of the surgical access port 300 to determine the relative spacing of the end effectors 195 b of the surgical instruments 195 with respect to a known point, such as the cylindrical member 110 or the longitudinal axis A 1 .
[0051] It will be understood that various modifications may be made to the embodiments of the presently disclosed surgical access ports. Therefore, the above description should not be construed as limiting, but merely as exemplifications of embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the present disclosure. | A surgical access port and method for achieving triangulation is disclosed, the surgical access port comprising a housing and an articulation structure. The housing is comprised of a cylindrical member having proximal and distal ends, and defining a longitudinal axis. The articulation structure is comprised of at least two lumens, each of the at least two tubular members disposed in a respective lumen, at least two rotating members disposed along each of the at least two tubular members, an actuating member, and a rigid member connecting each rotating member to each tubular member. The tubular members are configured to receive instruments for use in minimally invasive procedures. | 0 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed to an improved fork lift that is light-weight, leveraged (i.e., does not require counter weights), self-propelled, towable at highway speeds and compact enough to be mounted beneath trailer beds. The invention is also directed to a method for operating and transporting the improved fork lift.
2. Description of the Background Art
Significant problems may be encountered when transporting conventional fork lifts to or from work sites. Most fork lifts are provided with large counterweights and, therefore, are extremely heavy and require large, powerful vehicles for towing. Because of their weight and size, they often cannot be towed safely at highway speeds, and they then need to be carried on trailers having ramps and/or tilting beds.
Some conventional fork lifts can be secured directly to the rear of a truck or semi trailer. However, these types of fork lifts can only be used with trucks or semi trailers having a special mounting attachment and which are capable of supporting the weight of the fork lift (including some counterbalance weight) overhanging, i.e., protruding, from the extreme rear end of the truck. Further, the most efficient semi trailers have their wheels at the extreme rear of the semi trailer to provide the longest wheel base and the greatest carrying capacity. Conventional fork lifts cannot be carried at the rear end of these types of semi trailers inasmuch as the rear wheels interfere with the mounting assembly for the fork lift.
SUMMARY OF THE INVENTION
An object of the present invention is to provide a very light weight fork lift which can be towed safely at highway speeds, as can any conventional trailer of the same weight, and by pick-up size vehicles or even behind loaded light-to-medium capacity trucks.
A further object of the invention is to provide a fork lift that can be folded to a very low profile to facilitate transporting the fork lift beneath the deck and/or frame of a semi-trailer in the mid-section between semi dollies and rear wheels.
Still another object of the invention is to provide a fork lift with no counterbalance weights and which is capable of lifting extremely heavy loads.
These and other objects are achieved according to the present invention which comprises a light--approximately 2000 lbs.--fork lift having highway tires and drive axles. A steerable wheel can be elevated when the device is towed behind a vehicle. Alternatively, the fork lift can be compacted and mounted beneath the mid section of a semi trailer.
The fork lift of the present invention fundamentally alters the configuration of a conventional fork lift, using a leveraged support system to eliminate counter-weights, and a tilting platform with a translating fork lift carriage and moveable rear axle. While this modification of the conventional fork lift design does restrict the fork lift's use to limited lift-heights, its use for loading and unloading at normal bed heights is retained and the lift capacity is not diminished. In fact, the lift capacity of the fork lift of the present invention is comparable to much heavier conventional (heavily counterbalanced) fork lifts.
The invention might be best realized by mounting the device on a 3 wheel drive chassis with steerable third wheel or a 4 wheel drive chassis with two steerable wheels. The combined effects of a variable wheel-base and translating fork carriage--all under hydraulic control, for example--allow load positioning for maximum stability, minimum turning radius, and good tractive force despite the low ratio of unloaded vehicle weight to loaded vehicle weight. The two-wheel axle with traction locking differential may be driven directly by a hydraulic motor (which is driven directly by a combustion engine or by an electric motor), and may be of standard manufacture in a 3/4 or 1 ton pickup truck series. Driving hydraulic motors with combustion engines or electric power sources is well known in the art and will not be detailed here. A splined drive shaft coupling could be included to allow a quick disconnect mechanism to isolate the differential for towing while the steerable wheel is raised off the ground through the tow bar mechanism, the moveable axle being positioned to support the weight of the vehicle while in tow. The retractable axle-moving cylinders also allow the carriage-bearing platform to reach ground level with less inclination so that loads are moved more easily to a position that places the weight above the two wheel axle when the cylinders are extended.
The load bearing platform corresponds somewhat to a conventional fork lift mast that could be tilted to an extreme angle from vertical, except that the fork tilting means of the instant invention is mounted on the carriage on the apron side of the mast and has greater travel than conventional tilting means.
The platform also differs from a conventional fork lift mast in that carriage rollers are provided external to the mast, thus allowing the mast to be relatively flat instead of the usual channel shape with internal rollers. This flattened design is helpful in realizing a very low profile when other elevated members of the device are folded down toward the base frame of the fork lift. This design is intended to provide a fork lift that will fit securely under the mid section of a semi-trailer with the wheels of the fork lift situated under the deck on opposite sides of the two longitudinal "I" beams (or channels) extending along the length of conventional flat bed semi-trailers and with the frame and superstructure of the fork lift drawn up against the "I" beams while being transported. The remaining parts of the fork lift would fit beside the "I" beams and would be secured in that position, the prongs of the fork lift extending vertically along the outside edge of trailer bed and the shanks of the forks lying horizontal or prone.
Leveraging of loads while loading or unloading may be accomplished by resting the shoes attached to the platform end upon the ground or on the bed of the vehicle being serviced. This works easily with single side pallets such as used in the sod industry. The shoes can be provided with a simple locking clamp that attaches to the stake pocket support frames that extend along the sides of nearly all conventional flat-bed units so as to add safety and permit handling double-side pallets used in general freight operations. Where the semi-trailer is not provided with stake pocket support rails, an alternative maneuver might be needed. For example, inserting forks and lifting the outside edge of a pallet only slightly would allow a support to be inserted or wedged outboard of the shoes to provide platform support.
Another feature of the invention, particularly helpful when inserting forks on rough or uneven surfaces, can be obtained by by-passing the lifting cylinders on one side of the platform and causing the forks to be tilted laterally to a desired angle before lifting with cylinders on both sides of the platform. This maneuver can be accomplished using a selector valve that momentarily interrupts the flow of hydraulic fluid to cylinders on one side of the fork lift. It would also permit tilting a loaded set of forks to a more favorable center of gravity while traversing rough ground or along an inclined surface. Problems associated with an elevated load (e.g., a high center of gravity) would be significantly lessened. Tilting the platform laterally also leans the pallet away from adjacent objects, eliminating the need for side-shift mechanisms in most cases.
Additional advantages of the inventive fork lift include minimum damage to surfaces over which the fork lift travels, low fuel consumption and/or efficient use of battery operated power sources, and in transportation by aircraft or where basic machine weight is an important factor, light weight without sacrificing significant lifting ability.
There are also safety features inherent in the design for carrying beneath the vehicle deck. Besides being supported by four cylinders with locking valves holding the folded fork lift tightly against the carrying vehicle underframe and safety chains to reinforce security, any serious, albeit unlikely, complete structural failure would cause the fork lift to fall in front of the rear wheels of the semi rather than in front of following traffic, as in a rear mounted lift mishap. Such an unlikely disaster could be prevented by providing a warning system to warn the driver if any of the four contact points of the carried vehicle are loosened from firm contact with semi's underframe--such as audible sensors and/or warning lights. A fail-safe system is, therefore, virtually insured.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention is described in detail below with reference to the accompanying drawings, in which:
FIG. 1a is an operator side view of the inventive fork lift vehicle carrying a load and showing a partial profile of the differential drive system;
FIG. 1b is a view from the engine side of the fork lift showing lowered and elevated positions of the platform and an operator protection framework;
FIG. 2 is a plan view of the fork lift showing the variable wheelbase and two wheel drive system;
FIG. 3 is a view from the steerable wheel end of the fork lift;
FIG. 4 is a side view of the fork lift chassis beneath a semi trailer showing the fork lift on the ground and in a carrying position supported by mounting means;
FIG. 5a is a plan view of the operator protection framework re-assembled as a towing mechanism on the fork lift and a plan view of the fork lift frame used as a hydraulic reservoir;
FIG. 5b is a side view of the tow bar means used to elevate the steerable drive wheel and a side view of frame reservoir;
FIG. 5c is an end view of the frame as a hydraulic reservoir;
FIG. 6 is a side view of the shoes and an associated hydraulic means for controlling the position of the shoes;
FIG. 7 is an end view of one platform rail and the hydraulic means at the flange of the rail for controlling the position of the shoe;
FIG. 8 is an end view of one platform rail with the shoe in a vertical position;
FIG. 9 is a side view of the platform rail with means to handle two-sided pallets in the absence of stake rails;
FIG. 10 is a side view of the same means in FIG. 9 deployed and engaged for handling two-sided pallets without stake pocket rails;
FIG. 11 is an end view of one half of the carriage assembly, including the motor drive mechanism, as seen from the proximate end of the platform;
FIG. 12 is a side view of the carriage assembly on the platform;
FIG. 13 is a plan view of the carriage assembly on the platform;
FIG. 14 is a diagrammatic scheme of the hydraulic system and the electrical circuitry;
FIG. 15 is a plan view of a section of the chassis between the main frames showing the steering and driving mechanism for a single drive wheel and the position of the folded-down superstructure extending into this section;
FIG. 16 is a single wheel end view of the same section of the chassis as shown in FIG. 15; and
FIG. 17 is a profile view from the engine side of the same section of the chassis as shown in FIG. 15.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1a, 1b, 2 and 3 show a chassis of tubular framework consisting of two longitudinal sections 1 and 1a extending in parallel and connected by a cross-over frame section 32a seen in FIG. 2 and several arching frame segments 17, 24 and 32 best seen in FIG. 3. The two wheel assembly 23, as shown in FIG. 2, joins side members 1 and 1a by attachment to sliding sleeves 20 that are slidably mounted on members 1 and 1a. These provide rigidity to that section of the chassis that has no fixed cross members and serve as means to vary the wheel base while contributing to a light weight but strong chassis construction.
FIG. 1a shows a profile of the fork lift from the operator's side with a load in position for carrying. The position for operating is shown offset from the frame chassis and on the opposite side from the engine shown in FIGS. 2 and 3. The operator's seat 15, protector framework 74 and control valve stand 163 are supported by frame 1a in outboard locations by extensions of frame members 24 and 32 and by braces 160, 161, 64, and 65, respectively. Details of the section showing steerable wheel assembly 30 are shown in later figures. One each of five pairs of hydraulic cylinders 2, 6, 8, 10 and 19 are shown in attached positions for functions described later. Valve stand 163 and control valves 162 are shown pivoted on mount 164 and in a prone, alternate position in outline. This position is used when other superstructure elements are folded down for transportation by carrying vehicles. Also in outline are components of the two wheel axle assembly 23 and the drive train components of the assembly 126. Assembly 14 comprising the carriage with mounted forks and tilting means is driven by hydraulic motor 140 and travels on strands of chain 144, fastened near ends of supporting platform 4 and engaging an assemblage of sprockets 143. The carriage is supported on platform 4 by rollers 33 riding in channels of platform 4 and retained on platform 4 by rollers 34 (see FIG. 1b) under outboard flanges of platform 4.
FIG. 1b, which is a profile from the engine side of the fork lift, shows the fork lift with a shortened wheelbase accomplished by retracting hydraulic cylinders 19 which are mounted to chassis frames at attachments 18 and to sleeves at attachments 18a as shown in FIG. 1a. The shortened wheelbase permits lift arms 7, pivotally mounted at 38 on stand 13, to lower platform 4 which is pivotally mounted to arms 7 at mount 27. Shoes 29, pivotally mounted on the distal end of platform 4 will reach the ground and provide support for loads being picked up on fork assembly 14 for translating the load to a carrying position at the proximate end of the platform 4 as well as providing support for depositing loads on the ground.
Cylinders 2, attached pivotally to frame 24 and pivotally to platform 4 at mounts 41, control the proximate end of platform 4. Cylinder 6, pivotally attached at cross-member 32 of frame and to lift arms 7 at shackles 36, control elevation of platform 4. When cylinders 6 are extended, lift arms 7 pivot where mounted on stand 13 and raise platform 4 to the position shown in outline, which is a height used to service most load-carrying vehicles. Cylinders 2 follow the arc of lift arms 7 and can be operated to keep platform 4 parallel to the ground. During changes of elevation, the cylinders 10 are used to maintain the load in a level position, pivoting where attached to the carriage at 28 and to shanks 12 of forks at mount 40 as shown in FIG. 1a.
Cylinders 8, pivotally mounted on frame 24 and pivotally attached to stand 13 at the offset 152, serve to brace stand 13 in an upright position or with stand 13 pivoting at 35 as shown in FIG. 1a, may be retracted to achieve slightly greater elevation than the outline shows by further rotation of the base of each cylinder 6. Retraction of cylinders 8 also facilitates servicing vehicles with low deck heights by maintaining the horizontal position of platform 4 at lower levels.
Engine and pump assembly 25 and fuel tank 37 are shown supported by base 154 welded to frame 1 and to frame 24. Reference numeral 153 indicates cross-bracing to strengthen the two stands 13 mounted on 1 and 1a by joining them as a unitary structure.
The procedure for picking up and depositing a load at ground level is similar to standard fork lift operation. The forks are positioned low enough to enter or exit pallets or loads but just above the surface of the ground and are driven under or removed from below the load. The conventional lifting technique changes with the present invention as loads are first moved with the tilting action of the carriage forks, accomplishing weight transfer to or from load-carrying rollers 33 of the carriage. Picking up the load places the weight on the platform shoes on the ground until the carriage is translated to a load-carrying position and the axle is extended to provide vehicle stability and the shoes are lifted for traveling. Depositing loads reverses this procedure.
To operate at deck levels, the shoes are placed on the vehicle being serviced for support while loading or unloading and the carriage is moved to enter or exit from beneath the load and to move to the proper position while the forklift remains stationary. The fork lift is moved only when no support is needed at the distal end of the platform 4, as by the shoes.
FIG. 2 shows a retracted position of axle control cylinders 19 with wheels 22, and an outline of an extended position of assembly 23. Means for steering (assembly 16) is shown in simplified form with a tiller 170. The illustrated steering employs a torque energizer but other means of power steering could also be employed. The motor 49 and drive train assembly 126, which power assembly 23, are supported by frame 125 which is welded to sleeves 20, and is shown in FIG. 2. Assembly 126 includes a decoupling mechanism 128 on shaft 127, which shaft 127 is supported by bearings 121 and joined by U joint assembly 120 to the differential. Splined coupler 128 has internal splines that mesh with external splines on shaft 127 and the output shaft of motor 49. This mechanism is used only when the fork lift vehicle is to be towed.
FIG. 3 shows the pump and engine assembly 25 coupled for working the hydraulic system, a brace 159 for supporting the pump and an oblique brace 154' of the base for supporting engine assembly 25 are shown. Cross-member 32 is shown arched in its central section to allow passage of the drive motor 49 when axle assembly 23 is fully retracted. FIG. 3 also provides a simplified view showing how the steerable wheel assembly is mounted and showing the drive motor 50 for propelling the wheel. Another view of the operator protector assembly 74 and valve stand 163 with supporting structure 161 is also provided. Frame members 61 are shown in place over adapters 62 which are pinned to frame 24 by pins 67. Other pins 64a through 68c secure the rigid structure of the framework.
FIG. 4 shows the fork lift chassis on the ground in outline and the fully folded fork lift in a mounted position beneath a semi trailer. The following is a description of a method designed to be universally adaptable without modification to a semi trailer when stake pocket rails are available for lifting the fork lift. Several pairs of adapters are required, including tube inserts 21 for attaching cylinders 10 to distal ends of frames 1 and 1a, adapters 31 for attaching piston ends of cylinders 10, and adapters 31 for attaching cylinder 2 piston ends to the stake pocket railing on each side of the semi trailer.
Protector frame 74 is first collapsed into a carrying position by removing pins 64a and 65a as shown in FIG. 3 and sliding tube members 61 down on adapters 62. Then the framework will fold into the position shown and be part of a reduced profile of the fork lift. Cylinders 2 will be removed from operational positions and relocated to attach their base ends to proximate ends of frames 1 and 1a at mounts 70. Cylinders 10 also will be relocated to attach base ends to adapters 21. Forks 11 are tilted upright by hand so shanks 12 can be pinned to carriage in a prone position. Cylinders 6 are detached from lift arms 7 at shackle mounts, and cylinders 8 are retracted to pull down stands 13, bringing lift arms 7 and platform 4 to a folded position to complete the reduced profile. The procedure for remote control described in FIG. 14 details using the hydraulic and electric circuitry then allows the operator to maneuver the fork lift beneath the semi trailer deck and frame and to extend or retract the cylinders 2 and 10 to attach same to rail adapters 31. Closing cylinders 2 and 10 to completes the lifting operation so that the fork lift is positioned in the proper carrying position.
The stake pocket rails 101 are standard features of flat bed semi trailers and are welded to side members 102 of the semi deck along the entire length of the trailer. Other details shown are cross members 73 of the semi. Deck 100 is supported by cross members 73 and has side members 102 attached. I beams 72 are shown in an end view. These I beams, or in some cases channels, extend the length of the semi trailers and are the main supportive components to which cross members 73 are attached. Flanges 71 at the bottom of the I beam or channels provide surfaces to which the folded mid-section of the fork lift is held. The end sections of the fork lift with wheels' and other components are fit outside of I beams and under the deck.
FIGS. 5a, 5b and 5c are plan, profile and end views, respectively of the operator protection assembly re-assembled for use as a tow bar and steerable wheel elevator. To utilize members of framework 74 and so avoid carrying an additional structural framework used only for towing, a disassembly of protector 74 is required and may be illustrated with some reference to FIG. 3. The pins described in FIG. 3 as providing framework rigidity are removable and can be used to reassemble the protector as a tow bar as follows. Removing pins 68a (refer to FIG. 1b), 68b and 68c allow separation of members 60, 61, and 63. Pulling pins 64a and 65a permit telescoping members 61 down on adapters 62. If pins 67 are removed, two pairs of 61 and 62 combinations may be moved and attached with pins 64b at mounting positions 69 on upright frame sections of frame 24. Braces 63 of protector 74 now may be pinned to the two pairs of 61 and 62 by pins 64a. The four members 60 are now pinned to the two members 63 by one pin 65b and one pin 68c. Members 60 are also attached to the piston ends of cylinders 2 by pin 68b after cylinders 2 have been detached from operating connections to platform 4 and pivoted for use as tow bar lifting means.
Several items not part of protector 74 must be employed to adapt the framework to a towing vehicle. These are light and easily handled and provide the hitch 84 for ball or ring attachment on the towing vehicle tow point 79 and the brake activator unit 85 that applies pressure to the brake cylinders of fork lift assembly 23 for slowing or stopping when towing vehicle brakes are applied. Activator 85, a standard device, is a part of the tow bar adaptor 83 and also functions as a break-away safety feature in case of hitch failure.
Adaptor 83 is secured to members 60 and 61 with two long pins 80 and 81 that are not part of the operator protection framework. Final bracing of the reassembled tow bar is provided by two members 64 pinned to members 60 by a pin 65b and to adaptor 83 by a pin 68c.
The fork lift is now maneuvered to engage a hitch on the towing vehicle, and cylinders 2 are extended. This forces the tow bar hitch down on the towing vehicle mount and elevates the steerable wheel assembly 30 to a safe towing height, pivoting the fork lift on axle assembly 23. With de-coupling of the splined drive shaft to the two wheel differential, and with the addition of lights and safety chains, the fork lift is now ready to be towed at highway speeds.
To describe de-coupling of the drive shaft, further explanation of the drive train assembly 126 (see FIG. 2) is required. A short section of a splined and slip type drive shaft 120 with U-joints on both ends connects the differential of the two wheel assembly 23 to the shaft 127 which is supported by two bearings 121 provided on the assembly frame 125. The U joint assembly 120 relieves stress on the differential caused by torsion or mis-alignment as occurs in conventional drive train assemblies. Frame 125 is welded to sliding boxes 20 which slide on the frames 1 and 1a.
Shaft 127 has external splines on one end which mesh with internal splines of the coupler sleeve 128 which sleeve is fastened to the output shaft of hydraulic motor 49. The outboard bearing shown in FIG. 2 may not be needed if the motor has such a bearing. The splines on shaft 127 and the coupler sleeve 128 should be beveled for synchronizing engagement.
Hydraulic motor 49 is bolted to sliding base 124 which can move on frame 125 but is held by the springs 123 in a coupled position for driving the fork lift. To de-couple the motor 49 for towing purposes, the sliding base 124 is attached to frame 32a at fastener 129, the two wheel assembly 23 is locked with wheel brakes, the steering assembly 30 is allowed to float free, and the cylinders 19 hold the shafts apart while the fork lift is being towed.
To re-couple the motor 49 at the job site, the latch 129 is released, and operating valves for cylinders 19, assembly 30 and motor 49 are placed in float positions. Springs 123 should then pull shaft 127 and coupler 128 into the aligned, coupled position. If the shaft 127 and coupler 128 are not perfectly aligned, a slight rotation of the motor output shaft will permit the springs 123 to re-couple the shaft 127 and coupler 128.
FIGS. 5a, 5b and 5c show parts of the frame being used as a reservoir for hydraulic fluid, including the fluid routing and other components of a fluid temperature regulating system. The frame components hold approximately ten gallons of hydraulic fluid which is sufficient. A section of frame 17 serves as a manifold for return and case drain lines 132.
Internal pipes 134 that extend nearly the full length of frame members 1 and 1a direct circulation to the blunt ends of those members 1 and 1a where the fluid is returned between the internal pipes 134 and the interior of the frame members 1 and 1a. Frame arch 17 normally directs flow to both members 1 and 1a, while cross over frames 32 and 32a transfer fluid from member 1a to 1 and finally to the suction outlet 135 where the filter and pump are connected. Frame arch 24 serves as additional reservoir capacity.
A shut off valve 136 is positioned on the operator's side of the fork lift, just below a pipe adaptor block 137 which feeds into the frame 1a. Half of the fluid returned from the actuators and other hydraulic components flow into 1a. The balance of the fluid normally flows from the manifold on section 17 to frame 1 through pipe adaptor block 138.
When valve 136 is closed by the operator, all fluid is directed on return to the plumbing of frame 1, and circulation is reduced by half volume. This permits the viscosity of the hydraulic oil to be quickly raised when ambient and initial operating temperatures are low. As the fluid warms, or in generally hot weather, an open valve 136 doubles the circulation and radiant cooling to prevent the oil from overheating.
FIG. 6 shows a detailed profile of an end of platform 4 with shoes 29 in two positions and hydraulic means to achieve these positions.
FIG. 7 shows an end view of one rail of the platform 4 with one hydraulic means on the flange.
FIG. 8 shows an additional, smaller scale, end view of the rail of platform 4 with shoe 29 in a vertical position.
FIGS. 9 and 10 show details of the mechanism for providing platform support when handling two-sided pallets without stake pocket rails.
Handling two-sided pallets requires pivoting the shanks 12 at the mounts 86 to raise the forks so as to clear the bottom boards 115 above platform 4. (On two sided pallets, top boards 116 and bottom boards 115 are determined only by the orientation of pallet 17). In addition, an alternate means of supporting shoes 29 is required. Standard flat-bed semis have a stake pocket railing 101 lining both trailer side members 102 and welded to form a framework along the entire length of the semi, with openings to receive extensions 87 of shoes 29 when rotated about pivot point 88 to a vertical position. The figures also show two operating positions of cylinders 104, extended for vertical shoe and retracted for normal position or when shoes are on the ground.
FIGS. 9 and 10 are two profile views of the base support system 118 needed for loading and unloading two sided pallets on a vehicle without stake pocket railings. Base support plate 110 is shown retracted by cylinder 111 but still supported by retainer 109. FIG. 7 shows the width of this support plate 110 and passageway for movement between the top of shoe 29 and the bottom of platform 4 channel as well as the center mount position of cylinder 111. FIG. 10 shows an extended cylinder 111 having moved the base plate 110 to rest on the deck 100 of a vehicle in a gap provided when bottom boards 115 are raised at the outside of the pallet 117 by tines 11 of the fork lift carriage. Lifting slightly and tilting shanks 12 of the forks forward should cause the pallet to pivot thereby providing a gap for inserting the base support plate. The forks and the pallet load can then be pulled back to transfer the load to the carriage rollers 33 and the platform for movement to a normal carrying position of the fork lift. To place the pallet on the ground, the base plate 110 is withdrawn to allow the shoes to pivot to conform to the angle between the platform and the ground. High strength and hardened material should be used for base plates because these will support that portion of the load not borne by lifting cylinders 6.
An option for supporting the platform on a vehicle deck can be obtained with conventional prior art stabilizers shoes mounted on extensions of sleeves 20 and operated with the hydraulic system. With the wheel base extended this would provide vehicle support but not direct platform support so that lifting elements might require added strengthening and the capacity might be somewhat reduced. Also, stabilizers mounted on the frame would not be of benefit when the platform is at ground level--only platform shoes would be supportive then. The terrain must be suitable to use frame stabilizers, but slightly faster operations might result.
FIG. 11 is an end view of half the carriage assembly 14 including motor drive mechanism.
FIG. 12 is a side view of the carriage assembly mounted on platform 4.
FIG. 13 is a top view of the carriage assembly over a portion of platform 4.
FIG. 11 illustrates a portion of the carriage assembly affixed to one rib 108 that supports fork shank 12 on mount 39. Also shown is one end of spanning structures 145 and 146 that join ribs 108 of the carriage assembly. Span 145 and 146 are structurally joined by members 147 and 150 which support flanged motor base 149, cross-over shaft assembly 142 with bearings and sprockets on each end, and also idler sprockets group 143 which sprockets are supported on flanges of angle members 147.
FIG. 12 shows the carriage drive mechanism. Motor 140 with attached sprocket 141 drives the carriage on chains 144 by means of an idler sprocket group 143 and cross-over assembly 142.
FIG. 13 shows the parallel arrangement of the main components and the framework of the carriage assembly. Cross-over assembly 142 serves to transmit the force exerted by motor sprocket 141 to the other side the carriage, each side having a group of idler sprockets 143 which engage chains 144.
FIG. 14 shows the complete diagrammatic of the hydraulic and electric circuitry, as well as the circuitry necessary for an alternative propulsion method.
The system features groups of directional and selector valves and other hydraulic components including flow control, flow dividers and customary pumps, and a reservoir. Directional valves of group 162 are three-spool, 4-way manual control, open center, series type with float position on spool 1". An electric operated solenoid 4-way directional valve, open center, is indicated by reference numeral 46. Electric solenoid double selector valves are designated by reference numerals 54, 53, 52, 51 and 47. Manual double selector valves are designated by reference numerals 55 and 184. Manual single selector valves are designated by reference numerals 56 and 57. A spool type flow divider is designed by reference numeral 183. Gear type flow dividers are designated by reference numerals 77 and 78. Locking valves are designated by reference numerals 58 and 59. Unit 16a has internal valving operated by tiller handle 170 and provides torque generation for power steering. Cylinders 2, 6, 8, 10, 19, 104 and 111 are all double acting, although cylinders 6 may be telescoping single acting.
Electric components are mainly switches, mounted on tiller handle 170, valve handles 2' and 3' of valve group 162 and in two remote protected boxes, one on the carriage and one on the frame 24. All external switches are weather proof and power is supplied by battery 80. A two position momentary push button switch 196 is provided on the end of the tiller handle 170 with a first position energizing selector solenoids of 54 and 51 and a second position energizing said two selectors plus solenoids of selectors 52 and 53. Switches 76 and 43 are rocker type, double throw, momentary, three position switches with switch 76 being mounted on handle 2' of valve group 162 and switch 43 being mounted in a remote box. All switches in one remote box 300 are duplicated in a second remote box (not shown). Reference numeral 75 indicates a push button switch, single throw, NO mounted on handle 3' of 162 and used to over-ride NC limit switches 91 which shut off current to selectors 52 when the carriage reaches its end of travel on the chain strands. The four switches of 91 are fastened on two chain strands 144 on both ends so that the idler sprockets 143 will depress the actuators for the limit switches with a tooth of the sprockets and are duplicated to give redundancy for safety. Limit switches 91 are wired in series so any one will interrupt current to the selectors 52.
Other switches include engine ignition switch 9 and those enclosed in protected boxes and used only when mounting the fork lift. These give remote control from both ends of the vehicle and allow the following controls: reference numeral 42 indicates an NC emergency switch that opens the circuit for ignition and allows remote shut down of the engine if required; reference numeral 45 indicates an NO, single throw, momentary switch to energize 47; reference numeral 44 indicates the same type of switch as indicated by reference numeral 45 and is used to energize 51, which is also controlled by 196 during normal operations; and switch 43 has the same functions as switch 76 but can be operated from remote locations. Reference numeral 26 indicates a timer for selector 53 limiting the stroke of the cylinders 2, 6 when tilting the platform laterally.
As shown in FIG. 14, non-propulsion actions utilize control valves of 162, moving handles of manual directional valves and selectors and operating switches for solenoid valves. Work ports of spool 1" of 162 are connected to the primary ports of 54 which, in the neutral or A side, supply cylinders 19 for axle movement, and in the B side, when energized by 196, route flow to cylinders 104 or 111 as needed. Spool 2" work ports of 162 serve one primary port of 53 and the retracting ports of cylinders 6. Moving the handle of spool 2" activates cylinders 6, raising or lowering platform 4 evenly by passage of fluid through flow divider 78. Some lateral tilting of platform 4 can be achieved by closing 196 to the second position, energizing 53 changing exit flow from 53 to by-pass 78 and permitting a short stroke of one cylinder 6 before timer 26 interrupts current flow after a brief interval to prevent excessive travel of the piston before timer 26 restores current to 53.
Reference numeral 76 indicates a control located on the handle of spool 2" of 162 and permits various simultaneous functions while operating spool 2". Control 76 operates valve 46 by engaging the rocker switch with the operator's thumb. Work ports of 46 serve the primary ports of selector 51. Normally, the "A" side of 51 supplies fluid to cylinders 2 which are regulated by a flow divider 77 like cylinders 6 and may be by-passed for lateral tilting of proximate end of platform 4 by the method described above for the cylinders 6. En route from 51A flow passes through 57 and 59 freely in normal operation but these units serve a purpose described below in mounting the fork lift. If 196 is pressed to energize 51, flow from 46 goes to primary ports of 47 and thence to 52 located on carriage assembly 14. Flow continues on to cylinders 10, passing unrestricted through 56 and 58 to permit tilting of the carriage forks. If 196 is pressed to the second position, 52 is energized and ports 52 B are connected to the motor 140, thus moving the carriage. However, this also energizes 53 so the handle of spool 2" should be released to neutral to avoid laterally tilting the platform through 53. When carriage forks are loaded, movement should be controlled by the spool handle 3' since the solenoid valves do not start moving heavy loads smoothly.
Work ports of spool 3" go to 55 and beyond to the primary ports of 52. Spool 3" can then control cylinders 10 as an alternative to using 46, and, when 52 is energized by second position of 196, spool 3" will also control motor 140. Switch 75 on the handle 3' of spool 3" is used to over-ride limit switches 91 by restoring interrupted current to 52. Since 55 is a manual double selector, to activate cylinders 8, selector should be in easy reach and moved to position B.
Beyond these operational movements provisions has been made to use the hydraulic system to mount the fork lift by including remote control positions that avoid awkward efforts otherwise made by the operator under the bed of the carrying vehicle. After preparations described in detail pertaining to reducing the profile of the fork lift have been accomplished, remote switches can perform all of the hydraulic functions for positions and mounting. Using 43 to operate 46, the fork lift can be driven under the semi-trailer deck and I beams by engaging 45 and 44 which energize 47 and 51 which allows fluid to reach the motor 49 for moving the fork lift into position. With extended cylinders 2 and 10 connected to stake pocket rail adapters 31, both pairs of cylinders 2 and 10 can be lifted into position by manually changing 57 and 56 to the ports that send fluid through the locking valves 58 and 59 instead of bypassing these as in normal operations. This safety procedure is important and easily achieved and secure since the locking valve will not permit cylinders to drift open but requires forced extension by hydraulic pressure. Safety chains would add an additional factor of safety.
Circuitry from the valves to the actuators is such that logical sequences of action can be combined with minimum hand change positioning and use of both hands in an easy, coordinated manner. Only three manual valves in group 162 should be less confusing to a novice.
Flow dividers work automatically according to their circuitry, but are by-passed to achieve certain objectives.
Cylinders 104 or 111 are interchangeable units used when servicing vehicles with two sided pallets, whether or not stake pocket railings are present. The cylinders 104 or 111 are used each time extra platform support is needed. Fold-down cylinders 8 are used mainly to lower and raise the superstructure of the fork lift for underslung carrying or for servicing vehicles with lower deck surfaces than standard flat-bed vehicles.
Because the cylinders 6 provide lifting motion in an arc it is necessary to tilt the fork during the arc to keep the load in a stable, horizontal position. This is readily accomplished with use of valve 46 and the above described selector position options.
Beyond these two functions, valve 46 may be used to provide lateral tilt or adjustment of the platform 4. This is an important function in at least two respects and can likely only be done with two or four cylinder lifting mechanisms. On rough surfaces where one tine of the forks may be forced out of level alignment with a pallet or load, it may be difficult to place the uneven forks beneath loads. Lateral adjustment can be used to correct this problem. When a load is carried in the normal position, but the fork lift is travelling along the side of a slope, the center of gravity of the load will have to be shifted to accommodate the angle of the slope. Adjustment can only be made to one side of platform 4 so that side must be raised or lowered to the desired angle. Also, movement of only one side of the platform 4 will cause twisting or torsion of the superstructure so a timing device should limit operation of 53 to perhaps one second on, two seconds off, in order to prevent excessive movement of the cylinders 6.
FIG. 14 shows a dual pump and engine assembly 25'. Dual pump capacity is preferable since the propulsion and non-propulsions systems require separate circuits to accommodate the demands for different volumes and pressures. The motors 49 and 50 of the propulsion system for driving the loaded vehicle use significantly more energy than the actuators of circuit 187 which comprise the remainder of the hydraulic system and the torque energizer unit 16a shown in FIG. 2. This is state of the art differentiation made in hydraulic motor driven vehicles.
Pump 186 is an axial piston pump, pressure compensated with over-center, variable swash plate design. The swash plate may be controlled by a mechanical linkage to effect foot pedal manipulation, the pedal acting to control the direction and volume of fluid flow so that the motors will change direction, speed, and torque. The propulsion circuit fluid is first directed to flow divider 183, to selector valve 184, and to motor 49.
Fluid from port A of flow divider 183 is directed to port A of the double selector valve 184 and through the plumbing juncture to one port of the motor 49. Fluid from port B of the flow divider 183 is directed to port C of the valve 184. If position B of 184 is now selected, then the A side of the valve 184 is blocked and fluid entering port C moves internally to exit at port B and on to one port of motor 50. All wheel drive is thus achieved since both motors are pressurized on one port and opposite ports are able to return fluid passing through the motors back to pump 186. The motor 50 returns spent fluid through port C1 of 184, via an exit at port B1 of 184, the spent fluid joining flow from motor 49 and, exhausting through pump 186, returns to the reservoir 185.
Since the fluid volume is divided at flow divider 183 to service both motors, the amount of fluid to each motor is reduced, their speeds slowed and the torque increased. The equivalent of another gear ratio is thereby attained.
Selector 184 in the "A" position combines the volumes of fluid entering ports A and C of 184 and, in effect, by-passes divider 183 so that full flow enters motor 49 to drive the fork lift at the highest speed.
When motor 49 is the only motor used to drive the fork lift, motor 50 must be permitted to rotate freely. This may be done by using a motor 50 having a free-wheeling capability or by the free flowing circuit connecting both ports of motor 50 through the internal passage of selector 184 connecting A1 and C1.
Since provision has been made to operate from remote controls for mounting fork lift, a further extension of these controls could create possibilities of some robotics functions. Additional solenoid operated valves would be required to augment the manual valve system and provision would be needed to actuate the power steering unit with a small reversible electric motor. Then fork lift actions could be controlled at some distance by electric control lines or programmed for certain routine functions, operating a hydraulic system powered by motors, battery driven or by line current. For hazardous situations a radio signal control system is feasible; and with remote engine speed control, a full capacity fork lift operation is possible without operator risk.
FIG. 15 is an overhead view of a section of the chassis between the main frames showing the steering and driving mechanisms for a single wheel configuration, as well as the position of the folded down superstructure.
FIG. 16 is the single wheel end view of the same section shown in FIG. 15.
FIG. 17 is an engine side view of the same section shown in FIG. 15.
In FIG. 15 the sprocket and chain means used to steer the single wheel is shown. Steering is accomplished by moving tiller handle 170 to direction desired. Tiller operates torque energizer 16a for power steering but rotation is reversed through meshed gears 191 and 191a. So sprocket 178 on the same shaft 179 as driven gear 191a will drive chain 172 and turn wheel assembly 30 in proper direction, forward or reverse. Attachment of wheel assembly 30 to frames 24 and 17 is made through braces 174.
The turning/steering assembly 16 also comprises the following parts: sprocket 171 is supported on shaft 175 which is welded to the frame arch 177 of assembly 30, and the sprocket 171 is driven by chain 172, connected to driving sprocket 178. Sprocket 178 is fixed to shaft 179, supported at the top by pillow block bearing 189 and at the bottom by flange bearing 190. Flange bearing 190 is supported by mounting base 202 welded to 1a. Also on shaft 179 is driven gear 191a, meshed with driving gear 191 attached to shaft 192 as shown in FIG. 17. Tiller handle 170 is attached to input shaft of torque energizer 16a and has a two position switch affixed on handle end.
Mounts 197 are welded to frame 24 and support base ends of cylinders 2. Cylinders 2 are shown hanging vertically outside frame 24 as though being prepared for the transport mode. Extensions of platform 4 and lift arms 7 are shown in a folded-down position and attached to a retracted pair of cylinders 8.
FIGS. 15 and 16 show detail on the drive means for front tire 176. Motor 50 drives tire 176 through shaft 157 which is supported by bearings 158.
FIG. 16 omits cylinders 2 and shows cylinders 8 in retracted position but not connected to the outlined locations of platform 4 and lift arms 7. This is done to avoid confusing detail. Base mounts 198 of cylinders 8 are welded to frame 24. Bearings 173 are shown bolted to frames 174. The coupler 200 joins hub/wheel shaft 157 to driving motor 50, which is mounted on an angled structure 201 which is welded to wheel assembly arch 177 on horizontal and oblique supporting sections. More elements of steering assembly 16 are shown in profile. Included are energizer 16a and its support base 194 and coupler 193.
FIG. 17 shows the juxtaposition of folded platform 4 and lift arm 7 to flange 71 of an I beam 72 of a semi when the fork lift is in a carried position. Cylinder 8 is shown at an oblique angle downward placing the attached fold-down stand 13 in a near horizontal mode parallel to frame 1 with the extended mount where cylinder 8 is attached to 152 below the frame 1 top. Shown in outline form are the normal operating positions of platform 4, lift arms 7 and cylinders 2 and 8. Cylinder 2 is shown hanging vertical as in preparation for carrying mode. Mounting plate 69 for use with tow bar and mounts 70 to support cylinders 2 in carrying mode are shown.
Support for upper bearing 199 of shaft 192 is shown as a base 195 welded to frame 1. Support for the torque energizer 16a is provided by bracket 194 welded to frame section 155. The coupler 193 joins torque energizer 16a to shaft 192 at the output end of the torque energizer.
Although the instant invention has been described in significant detail above, numerous modifications are possible without departing from the spirit and scope of this invention as described above and as defined in the claims which follow. | An improved, self-propelled fork lift having a variable wheelbase, a tilting and leveraged platform, and a translating fork carriage, all under hydraulic control, to permit load positioning for maximum stability, minimum turning radius, and good tractive force despite a relatively low ratio of vehicle weight to loaded condition. The improved fork lift is towable at highway speeds and is collapsible for mounting beneath the mid section of a semi trailer. | 1 |
CROSS REFERENCES TO RELATED APPLICATIONS
The present application is a continuation of U.S. application Ser. No. 15/380,927, filed Dec. 15, 2016, which is a continuation of U.S. application Ser. No. 14/818,610, filed Aug. 5, 2015, which is a continuation of U.S. application Ser. No. 14/536,106, filed Nov. 7, 2014, now U.S. Pat. No. 9,168,755, which is a continuation of U.S. application Ser. No. 14/284,829, filed May 22, 2014, now U.S. Pat. No. 9,085,148, which is a continuation of U.S. application Ser. No.14/104,955, filed Dec. 12, 2013, now U.S. Pat. No. 8,905,519, which is a continuation of U.S. application Ser. No. 13/736,006, filed Jan. 7, 2013, now U.S. Pat. No. 8,662,636, which is a continuation of U.S. application Ser. No. 13/162,525, filed Jun 16, 2011, now U.S. Pat. No. 8,556,386, which is a continuation of U.S. application Ser. No. 12/563,967, filed Sep. 21, 2009, now U.S. Pat. No. 7,984,970, which is a continuation of U.S. application Ser. No. 11/730,788, filed Apr. 4, 2007, now U.S. Pat. No. 7,604,314, which is a continuation of U.S. application Ser. No. 10/990,527, filed on Nov. 18, 2004, now U.S. Pat. No. 7,210,762, which is a continuation of U.S. application Ser. No. 10/803,922, filed on Mar. 19, 2004, now U.S. Pat. No. 6,830,315, which is a continuation of U.S. application Ser. No. 09/609,140, filed on Jun. 30, 2000, now U.S. Pat. No. 6,755,513, which claims priority to Australian applications PQ1304, PA1305, and PQ1306, all filed on Jun. 30, 1999, all of all of which are herein incorporated by reference in their entirety for all purposes.
FIELD OF THE INVENTION
This invention relates to the field of ink jet printing systems, and more specifically to a support structure and ink supply arrangement for a printhead assembly and such printhead assemblies for ink jet printing systems.
DESCRIPTION OF THE PRIOR ART
Micro-electromechanical systems (“MEMS”), fabricated using standard VLSI semi-conductor chip fabrication techniques, are becoming increasingly popular as new applications are developed. Such devices are becoming widely used for sensing (for example accelerometers for automotive airbags), inkjet printing, micro-fluidics, and other applications. The use of semi-conductor fabrication techniques allows MEMS to be interfaced very readily with microelectronics. A broad survey of the field and of prior art in relation thereto is provided in an article entitled “The Broad Sweep of Integrated Micro-Systems”, by S. Tom Picraux and Paul McWhorter, in IEEE Spectrum, December 1998, pp 24-33.
In PCT Application No. PCT/AU98/00550. the entire contents of which is incorporated herein by reference, an inkjet printing device has been described which utilizes MEMS processing techniques in the construction of a thermal-bend-actuator-type device for the ejection of a fluid, such as an ink, from a nozzle chamber. Such ink ejector devices will be referred to hereinafter as MEMJETs. The technology there described is intended as an alternative to existing technologies for inkjet printing, such as Thermal Ink Jet (TD) or “Bubble Jet” technology developed mainly by the manufacturers Canon and Hewlett Packard, and Piezoelectric Ink Jet (PIJ) devices, as used for example by the manufacturers Epson and Tektronix.
While TIJ and PIJ technologies have been developed to very high levels of performance since their introduction, MEMJET technology is able to offer significant advantages over these technologies. Potential advantages include higher speeds of operation and the ability to provide higher resolution than obtainable with other technologies. Similarly, MEMJET Technology provides the ability to manufacture monolithic printhead devices incorporating a large number of nozzles and of such size as to span all or a large part of a page (or other print surface), so that pagewidth printing can be achieved without any need to mechanically traverse a small printhead across the width of a page, as in typical existing inkjet printers.
It has been found difficult to manufacture a long TIJ printhead for full-pagewidth printing. This is mainly because of the high power consumption of TIJ devices and the problem associated therewith of providing an adequate power supply for the printhead. Similarly, waste heat removal from the printhead to prevent boiling of the ink provides a challenge to the layout of such printhead. Also, differential thermal expansion over the length of a long TIJ-printhead my lead to severe nozzle alignment difficulties.
Different problems have been found to attend the manufacture of long PIJ printheads for large- or full-page-width printing. These include acoustic crosstalk between nozzles due to similar time scales of drop ejection and reflection of acoustic pulses within the printhead. Further, silicon is not a piezoelectric material, and is very difficult to integrate with CMOS chips, so that separate external connections are required for every nozzle.
Accordingly, manufacturing costs are very high compared to technologies such as MEMJET in which a monolithic device may be fabricated using established techniques, yet incorporate very large numbers of individual nozzles. Reference should be made to the aforementioned PCT application for detailed information on the manufacture of MEMJET inkjet printhead chips; individual MEMJET printhead chips will here be referred to simply as printhead segments. A printhead assembly will usually incorporate a number of such printhead segments.
While MEMJET technology has the advantage of allowing the cost effective manufacture of long monolithic printheads, it has nevertheless been found desirable to use a number of individual printhead segments (CMOS chips) placed substantially end-to-end where large widths of printing are to be provided. This is because chip production yields decrease substantially as chip lengths increase, so that costs increase. Of course, some printing applications, such as plan printing and other commercial printing, require printing widths which are beyond the maximum length that is practical for successful printhead chip manufacture.
SUMMARY OF THE INVENTION
According to an aspect of the present disclosure, an inkjet printhead assembly includes an elongate support having a plurality of internal webs protruding from a base section to define a plurality of parallel ink supply channels; a shim mounted on the support and defining a plurality of rows of openings through which ink from respective supply channels is provided; and a plurality of elongate printhead modules mounted serially on the shim. Each module includes a carrier carrying a printhead. Each carrier defines a plurality of ink supply passages through which ink passes to the printhead from respective rows of the openings. Either end of each carrier defines complementary formations such that adjacent pairs of the carriers nest together. The plurality of internal webs protrude from the base section to define a semicircular recess in which the shim is received. The shim is received in the semicircular recess such that the each of the plurality of rows respectively align with one of the plurality of parallel ink channels.
BRIEF DESCRIPTION OF THE FIGURES
FIG. 1 is a perspective view of one embodiment of an inkjet printhead assembly according to the invention;
FIG. 2 is a perspective view of the inkjet printhead assembly shown in FIG. 1 , with a cover component (shield plate) removed;
FIG. 3 is an exploded perspective view of a part only of the inkjet printhead assembly shown in FIG. 1 ;
FIG. 4 is a perspective partial view of a support extrusion forming part of the inkjet printhead assembly shown in FIG. 3 ;
FIG. 5 is a perspective view of a sealing shim forming part of the inkjet printhead assembly shown in FIG. 3 ;
FIG. 6 is a perspective view of a printhead segment carrier shown in FIG. 3 ;
FIG. 7 is a further perspective view of the printhead segment carrier shown in FIG. 6 ;
FIG. 8 is a bottom elevation of the printhead carrier shown in FIGS. 6 and 7 (as viewed in the direction of arrow “X” in FIG. 6 );
FIG. 9 is a top elevation of the printhead carrier shown in FIGS. 6 and 7 (as viewed in the direction of arrow “Y” in FIG. 6 );
FIG. 10 is a cross-sectional view of the printhead carrier of FIGS. 6 and 7 taken at station “B-B” in FIG. 8 ;
FIG. 11 is a cross-sectional view of the printhead carrier of FIGS. 6 and 7 taken at station “A-A” in FIG. 8 ;
FIG. 11A is an enlarged cross-sectional view of the seating arrangement of a printhead segment at the print carrier as per detail “E” in FIG. 11 ;
FIG. 12 is a cross-sectional view of the printhead carrier of FIGS. 6 and 7 taken at station “D-D” in FIG. 8 ;
FIG. 13 is an external perspective view of an end cap of the inkjet printhead assembly shown in FIG. 1 ;
FIG. 14 is an internal perspective view of the end cap shown in FIG. 13
FIG. 15 is an external perspective view of a further end cap of the inkjet printhead assembly shown in FIG. 1 ;
FIG. 16 is an internal perspective view of the end cap shown in FIG. 15 ;
FIG. 17 is a perspective view (from the bottom) of the printhead assembly shown in FIG. 1 ;
FIG. 18 is a perspective view of a part assembly of a support profile and modified sealing shim which are alternatives to those shown in FIGS. 4 and 5 ;
FIG. 19 is a perspective view showing a molding tool and illustrating the basic arrangement of die components for injection molding of the printhead carrier shown in FIGS. 6 and 7 ;
FIG. 20 is a schematic cross-section of the injection molding tool shown in FIG. 19 , in an open position; and
FIG. 21 is a schematic transverse cross-section of the injection molding tool shown in FIG. 19 , in a closed position, taken at a station corresponding to the station “A-A” in FIG. 8 .
DESCRIPTION OF THE PREFERRED EMBODIMENT
FIG. 1 shows in perspective view an inkjet printhead assembly 1 according to one aspect of the invention and, in phantom outline, a surface 2 on which printing is to be effected. In use, the surface 2 moves relative to the assembly 1 in a direction indicated by arrow 3 and transverse to the main extension of assembly 1 (this direction is hereinafter also referred to as the transverse direction of the assembly 1 ), so that elongate printhead segments 4 , in particular MEMJET printhead segments such as described in the above-mentioned PCT/AU98/00550. placed in stepped overlapping sequence along the lengthwise extension of assembly 1 can print simultaneously across substantially the entire width of the surface. The assembly 1 includes a shield plate 5 with which the surface 2 may come into sliding contact during such printing. Shield plate 5 has slots 6 , each corresponding to one of the printhead segments 4 , and through which ink ejected by that printhead segment 4 can reach surface 2 .
The particular assembly 1 shown in FIG. 1 has eleven printhead segments 4 , each capable of printing along a 2 cm printing length (or, in other words, within a printing range extending 2 cm) in a direction parallel to arrow 7 (hereinafter also called the lengthwise direction of the assembly 1 ) and is suitable for single-pass printing of a portrait A4-letter size page. However, this number of printhead segments 4 and their length are in no way limiting, the invention being applicable to printhead assemblies of varying lengths and incorporating other required numbers of printhead segments 4 .
The slots 6 and the printhead segments 4 are arranged along two parallel lines in the lengthwise direction, with the printing length of each segment 4 (other than the endmost segments 4 ) slightly overlapping that of its two neighboring segments 4 in the other line. The printing length of each of the two endmost segments 4 overlaps the printing length of its nearest neighbour in the other row at one end only. Thus printing across the surface 2 is possible without gaps in the lengthwise direction of the assembly. In the particular assembly shown, the overlap is approximately 1 mm at each end of the 2 cm printing length, but this figure is by no means limiting.
FIG. 2 shows assembly 1 with the shield plate 5 removed. Each printhead segment 4 is secured to an associated one printhead segment carrier 8 that will be described below in more detail. Also secured to each printhead segment 4 is a tape automated bonded (TAB) film 9 which carries signal and power connections (not individually shown) to the associated printhead segment 4 . Each TAB film 9 is closely wrapped around an extruded support profile 10 (whose function will be explained below) that houses and supports carriers 8 , and they each terminate onto a printed circuit board (PCB) 11 secured to the profile 10 on a side thereof opposite to that where the printhead segments 4 are mounted, see also FIG. 3 .
FIG. 3 shows an exploded perspective view of a part only of assembly 1 . In this view, three only of the printhead segment carriers 8 are shown numbered 8 a . 8 b and 8 c , and only the printhead segment 4 associated with printhead segment carrier 8 a is shown and numbered 4 a . The TAB film 9 associated therewith is terminated at one end on an outer face of the printhead segment 4 and is otherwise shown (for clarity purposes) in the unwound, flat state it has before being wound around profile 10 and connected to PCB 11 . As can be seen in FIG. 3 , printhead segment carriers 8 are received (and secured), together with an interposed sealing shim 25 , in a slot 21 of half-circular cross-sectional shape in profile member 10 as will be explained in more detail below.
FIG. 4 illustrates a cross-section of the profile member 10 (which is preferably an aluminium alloy extrusion). This component serves as a frame and/or support structure for the printhead segment carriers 8 (with their associated printhead segments 4 and TAB films 9 ), the PCB 11 and shield plate 5 . It also serves as an integral ink supply arrangement for the printhead segments 4 , as will become clearer later.
Profile member 10 is of semi-open cross-section, with a peripheral, structured wall 12 of uniform thickness. Free, opposing, lengthwise running edges 16 ′, 17 ′ of side wall sections 16 and 17 respectively of wall 12 border or delineate a gap 13 in wall 12 extending along the entire length of profile member 10 . Profile member 10 has three internal webs 14 a . 14 b . 14 c that stand out from a base wall section 15 of peripheral wall 12 into the interior of member 10 , so as to define together with side wall sections 16 and 17 a total of four (4) ink supply channels 20 a . 20 b . 20 c and 20 d which are open towards the gap 13 . The shapes, proportions and relative arrangement of the webs and wall sections 14 a - c . 16 , 17 are such that their respective free edges 14 a ′, 14 b ′, 14 c ′ and 16 ′, 17 ′, as viewed in the lengthwise direction and cross-section of profile member 10 , define points on a semi-circle (indicated by a dotted line at “a” in FIG. 4 ). In other words, an open slot 21 of semicircular cross-sectional shape is defined along one side of profile member 10 that runs along its extension, with each of the ink supply channels 20 a - d opening into common slot 21 .
Base wall section 15 of profile member 10 also includes a serrated channel 22 opening towards the exterior of member 10 , which, as best seen in FIG. 3 , serves to receive fastening screws 23 to fixedly secure PCB 11 onto profile member 10 in a form-fitting manner between free edges 24 (see FIG. 4 ) of longitudinally extending curved webs 107 extending from the base wall section 15 of profile member 10 .
Referring again to FIG. 3 , sealing shim 25 is received (and secured) within the half-circular open slot 21 . As best seen in FIGS. 3 and 5 , shim 25 includes four lengthwise extending rows of rectangular openings 26 that are equidistantly spaced in peripheral (widthwise) direction of shim 25 , so that three lengthwise-extending web sections 27 between the aperture rows (of which two are visible in FIG. 5 ) are located so as to be brought into abutting engagement against the free edges 14 a ′, 14 b ′ and 14 c ′ of webs 14 a . 14 b . 14 c of profile member 10 when shim 25 is received in slot 21 . As can be gleaned from FIG. 4 , the free edges 16 ′ and 17 ′ of side wall sections 16 , 17 of profile member 10 are shaped such as to provide a form-lock for retaining the lengthwise extending edges 28 of shim member 25 as a snap fit. In other words, once shim 25 is mounted in profile member 10 , it provides a perforated bottom for slot 21 , which allows passage of inks from the ink supply channels 20 a - d through apertures 26 in shim 25 into slot 21 . A glue or sealant is provided where shim webs 27 and edges 28 mate with the free edges 14 a ′, 14 b ′, 14 c ′, 16 ′ and 17 ′ of profile member 10 , thereby preventing cross-leakage between ink supply channels 20 a - d along the abutting interfaces between shim 25 and profile member 10 . It will be noted from FIG. 5 that not all apertures 26 have the same opening size. Reference numerals 26 ′ indicate two such smaller apertures, the significance of which is described below, which are present in each aperture row at predetermined aperture intervals. A typical size for the full-sized apertures 26 is 2 mm×2 mm. The shim is preferably of stainless steel, but a plastics sheet material may also be used.
Turning next to FIGS. 6-12 , these illustrate in different views and sections a typical printhead segment carrier 8 . Carrier 8 is preferably a single micro-injection molded part made of a suitable temperature and abrasion resistant and form-holding plastics material. (A further manufacturing operation is carried out subsequent to molding, as described below.) As best seen in FIGS. 6 and 7 , the overall external shape of carrier 8 can be described illustratively as a diametrically slit half cylinder, with a half-circular back face 91 , a partly planar front face 82 and stepped end faces 83 . FIG. 8 shows a plan view of back face 91 and FIG. 9 shows a plan view of front face 82 .
Carrier 8 has a plane of symmetry halfway along, and perpendicular to, its length, that is, as indicated by lines marked “b” in FIGS. 8 and 10 which lie in the plane. Line “b” as shown in FIG. 8 extends in a direction that will hereinafter be described as transverse to the carrier 8 . (When the carrier 8 is installed in the assembly 1 , this direction is the same as the transverse direction of the assembly 1 .) Lines marked “c” in FIGS. 8, 9, 11 and 12 together similarly indicate the position of an imaginary plane which lies between two sections of the carrier 8 of different length and whose overall cross-sectional shapes are quarter circles. Line “c” as shown in FIG. 9 extends in a direction that will hereinafter be described as lengthwise in the carrier 8 . (When the carrier 8 is installed in the assembly 1 this direction is the same as the lengthwise direction of the assembly 1 .) These sections will hereinafter be referred to as the shorter and longer “quarter cylinder” sections 8 ′ and 8 ″, respectively, to allow referenced description of features of the carrier 8 .
Each stepped end face 83 includes respective outer faces 84 ′ and 85 ′ of quarter-circular-sector shaped end walls 84 and 85 and an outer face 86 ′ of an intermediate step wall 86 between and perpendicular to end walls 84 , 85 . This configuration enables carriers 8 to be placed in the slot 21 of profile 10 in such a way that adjoining carriers 8 overlap in the lengthwise direction with the step walls 86 of pairs of neighbouring carriers 8 facing each and overlapping. Such an “interlocking” arrangement is shown in FIG. 2 , wherein it is apparent that every one of the eleven (11) carriers 8 has an orientation, relative to its neighbouring carrier or carriers 8 , such that faces 84 ′ and 85 ′ of each carrier lie adjacent to faces 85 ′ and 84 ′, respectively, of its neighbouring carrier(s) 8 . In other words, each carrier 8 is so oriented in relation to its neighbouring carrier(s) as to be rotated relatively by 180° about an axis perpendicular to the face 82 . In essence, neighbouring carriers 8 will align along a common lengthwise-oriented plane defined between the step walls 86 of adjoining carriers 8 , shorter and longer quarter cylinder sections 8 ′ and 8 ″ of adjoining carriers 8 alternating with one another along the extension of slot 21 .
Turning now in particular to FIGS. 7, 9, 11 and Ha, front face 82 of carrier 8 includes on the shorter quarter cylinder section 8 ′ a planar surface 81 . Formed in surface 81 are two handling (i.e. pick-up) slots 87 whose purpose is described below. On the longer quarter cylinder section 8 ″, front face 82 incorporates a mounting or support surface 88 recessed with respect to edges 89 of sector-shaped end walls 84 that are co-planar with the surface 81 . As best seen in FIG. 11 , mounting surface 88 recedes in slanting fashion from a point on the back face 91 of the longer quarter cylinder section 8 ″ towards an elongate recess 90 extending lengthwise between walls 84 . Recess 90 is of constant transverse cross-section along its length and is shaped to receive in form-fitting manner one printhead segment 4 . FIG. 11 a shows, schematically only, printhead segment 4 in position in recess 90 . Mounting surface 88 is provided to accommodate in flush manner with respect to the surface 81 the terminal end of TAB film 9 connected to printhead segment 4 , as is best seen in FIG. 3 . Due to the opposing orientations of neighbouring carriers 8 along the extension of assembly 1 , the TAB films 9 associated with any two neighbouring carriers 8 lead away from their respective segments 4 in opposite transverse directions, as can be seen in FIG. 2 .
Referring now to FIGS. 6, 7, 8, 10 and 11 in particular, four rows of ink galleries or ink supply passages 92 a to 92 d of generally quadrilateral cross-section are formed within the printhead segment carrier 8 . The ink galleries 92 a to 92 d act as conduits for ink to pass from the ink supply passages 20 a to 20 d . respectively, via openings 26 in the shim 25 , to the printhead segment 4 mounted in recess 90 of the printhead segment carrier 8 . Galleries 92 a - 92 d extend in quasi-radial arrangement between the half-cylindrical back face 91 of carrier 8 and recess 90 located in the longer quarter cylinder section 8 ″ at front face 82 . The expression “quasi-radial” is used here because recess 90 is not located at a transversely central position across carrier 8 , but is offset into the longer quarter cylinder section 8 ″, so that the inner ends of galleries 92 a - 92 d are similarly off-set, as further described below. Each gallery 92 has a rectangular opening 93 at back face 91 . All rectangular openings 93 have the same dimension in a peripheral direction of face 91 and are equidistantly spaced around the periphery of back face 91 . Moreover, the openings 93 are symmetrically located on opposing sides of the boundary between shorter quarter cylinder section 8 ′ and longer quarter cylinder section 8 ″, as represented in FIG. 11 by the line marked “c”. All openings 93 in the shorter quarter cylinder section 8 ′ are of the same dimension, and equispaced, in the lengthwise direction. This also applies to the openings 93 in the longer quarter cylinder section 8 ″, except that openings 93 ′ in the longer quarter cylinder section 8 ″ which correspond to endmost galleries 92 a ° and 92 b ′ are of smaller dimension in the lengthwise direction than the other galleries 92 a and 92 b, respectively.
By way of further description of how the galleries 92 a to 92 d are formed, printhead segment carrier 8 includes a set of five (5) quasi-radially converging walls 95 which converge from back face 91 towards recess 90 at front face 82 and two of which define the faces 81 and 88 . The walls 95 perpendicularly intersect seven (7) generally semi-circular and mutually parallel walls 97 that are equidistantly spaced apart in lengthwise extension of carrier 8 . Of walls 97 , the two endmost ones extending into the shorter quarter cylinder section 8 ′ provide the end walls 85 of stepped end faces 83 , thereby defining twenty-four (24) quasi-radially extending ink galleries 92 a to 92 d . of quadrilateral cross-section, in four lengthwise-extending rows each of six galleries. The walls 97 are parallel to and lie between end walls 84 .
FIG. 12 shows a cross-section through one of the lengthwise end portions of longer quarter cylinder section 8 ″ of carrier 8 . By comparison with FIG. 11 (which shows a cross-section through the main body of carrier 8 ), it will be seen that the quasi-radially extending walls 95 bordering end gallery 92 a ′ have the same shape as walls 95 which border galleries 92 a . whereas gallery 92 b ′ is bounded on one side by intermediate step wall 86 and by a wall 108 . FIG. 12 also shows a wall 111 and a wall formation 112 on the wall 86 , the purpose of which is explained below.
Converging walls 95 are so shaped at their radially inner ends as to define four ink delivery slots 96 a to 96 d which extend lengthwise in the carrier 8 and which open into the recess 90 , as best seen in FIGS. 11 and 11 a . The slots 96 a to 96 d extend between the opposite end walls 84 of longer quarter cylinder section 8 ″ and pierce through the inner parallel walls 97 , including the endwise opposite walls 97 which form the end walls 85 of the shorter cylinder section 8 ′. FIG. 12 shows how slots 96 a to 96 d extend and are formed within the end portions of the longer quarter cylinder section 8 ″, where the slots 96 a to 96 d are defined by the terminal ends of two of walls 95 , walls 108 , 111 and wall formation 112 , wall formation 112 in effect being a perpendicular lip of intermediate step wall 86 .
The widths and transverse positioning of the ink delivery slots 96 a to 96 d are such that when a printhead segment 4 is received in recess 90 , a respective one of the slots 96 a - 96 d will be in fluid communication with one only of four lengthwise oriented rows of ink supply holes 41 on rear face 42 of printhead segment 4 , compare FIG. 11 a . Each row of ink supply holes 41 corresponds to a row of printhead nozzles 43 running lengthwise along the front face 44 of printhead segment 4 . In the schematic representation of segment 4 in FIG. 11 a . the positions of holes 41 and nozzles are indicated by dots, with no attempt made to show their actual construction. Reference to PCT Application No. PCT/AU98/00550 will provide further details of the make-up of segment 4 . Accordingly, each of the ink galleries of a specific gallery row 92 a to 92 d is in fluid communication with one only of the rows of ink supply holes 41 . Once a printhead segment 4 is form fittingly received in recess 90 and sealingly secured with its rear face 42 against the terminal inner ends of walls 95 , and wall formations 108 , 111 and 112 (using a suitable sealant or adhesive), cross-communication and ink bleeding between slots 96 a - 96 d via recess 90 is not possible.
When a carrier 8 is installed in its correct position lengthwise in the slot 21 of profile 10 , compare FIG. 3 , each opening 93 in its back face 91 aligns with one of the openings 26 in the shim 25 . Smaller openings 26 ′ in the shim 25 correspond to openings 93 ′ of the smaller galleries 92 a ′ and 92 b ′ of carrier 8 . Therefore, each one of the ink supply channels 20 a to 20 d is in fluid communication with one only of the rows of ink galleries 92 a to 92 d, respectively, and so with one only of the slots 96 a to 96 d respectively and only one of the rows of ink supply holes 41 . A suitable glue or sealant is provided at mating surfaces of the shim 25 and the carrier 8 to prevent leakage of ink from any of the channels 20 a to 20 d to an incorrect one of the galleries 92 , as described further below. The symmetrical location (mentioned above) of openings 93 on back face 91 of carrier 8 , which is matched by the openings 26 in shim 25 , enables the carrier 8 to be received in the slot 21 in either of the two orientations shown in FIG. 3 , with in both cases each row of ink galleries 92 a to 92 d aligning with one only of the ink supply channels 20 a to 20 d.
As mentioned above, the longer quarter cylinder section 8 ″ of carrier 8 has two galleries 92 a ′ and 92 b ′ at each lengthwise end that have no counterpart in the shorter section 8 ′. These galleries 92 a ″ and 92 b ′ provide direct ink supply paths to that part of their associated ink delivery slots 96 a and 96 b located in the longer quarter cylinder section 8 ″, and thus to the ink supply holes 41 of the printhead segment 4 that are located near the lengthwise terminal ends of segment 4 when secured within recess 90 . There are no corresponding quasi-radial galleries to supply ink to the end regions of the slots 96 c and 96 d . However, it is desirable to provide direct ink supply to the end portions of the other two slots 96 c and 96 d as well, without reliance on lengthwise flow within the slots 96 c and 96 d of ink that has passed through galleries 92 c and 92 d respectively. This is ensured by provision of ink supply chambers 99 c and 99 d which are shown in FIG. 12 and which supply ink to the slots 96 c and 96 d . respectively. Chambers 99 c and 99 d are bounded by the walls 84 , 86 , and wall formations 108 , 111 and 112 , are open towards slots 96 c and 96 d . respectively, and are in fluid communication through holes 113 and 114 in an endmost wall 97 with endmost ones of ink galleries 92 c and 92 d . respectively. The holes 113 and 114 have outlines shaped to match the transverse cross-sectional shapes of the chambers 99 c and 99 d . respectively, as shown in FIG. 12 , and the means whereby holes 113 and 114 are formed is described below.
FIGS. 13 and 14 show a first end cap 50 which is sealingly secured to an open terminal longitudinal end of profile member 10 , as may be seen in FIGS. 1 and 2 . Cap 50 is molded from a plastics material and it incorporates a generally planar wall portion 51 that extends perpendicularly to a lengthwise axis of profile member 10 . Four tubular stubs 55 a - 55 d are integrally moulded with planar wall portion 51 on side 52 of wall portion 51 which will face away from support profile 10 when end cap 50 is secured thereto. On the planar wall side 53 which will face the longitudinal terminal end of support profile 10 (see FIG. 14 ), four hollow-shaped stubs 57 a - 57 d are integrally moulded with planar wall portion 51 . As best seen in FIG. 14 , ink supply conduits 56 a to 56 d are defined within tubular stubs 55 a to 55 d respectively, extend through planar wall portion 51 , and open within shaped stubs 57 a to 57 d . respectively, located on the other sides of cap 50 .
The shape of each one of the insert stubs 57 a to 57 d . as seen in transverse cross-section, corresponds respectively to one of the ink supply channels 20 a to 20 d of support profile so that, when cap 50 is secured to the terminal axial end of support profile 10 , the walls of stubs 57 a - 57 d are received form-fittingly in ink supply channels 20 a - 20 d to prevent cross-migration of ink therebetween. The face 53 abuts a terminal end face of the profile 10 . Preferably, glue or a sealant can be applied to the mating surfaces of profile 10 and cap 50 to enhance the sealing function.
The tubular stubs 55 a - 55 d serve as female connectors for pliable/flexible ink supply hoses (not illustrated) that can be connected thereto sealingly, thereby to supply ink to the integral ink supply channels 20 a - 20 d of support profile 10 .
A further stub 58 , D-shaped in transverse cross-section, is integrally molded to planar wall portion 51 at side 53 . In completed assembly 1 , the curved wall 71 , semi-circular in transverse cross-section, of retaining stub 58 seals against the inside surface of shim 25 , with the terminal edge of shim 25 abutting a peripheral ridge 72 around the stub 58 . Preferably, to avoid cross-migration of ink among channels 20 a to 20 d . an adhesive or sealant is provided between the shim 25 and wall 71 . The stub 58 assists in retaining the shim 25 in slot 21 .
A second end cap 60 , which is shown in FIGS. 15 and 16 , is mounted to the other end of the profile 10 opposite to cap 50 . Cap 60 has insert stubs 67 a to 67 d and a retaining stub 68 identical in arrangement and shape to stubs 57 a to 57 d and stub 58 , respectively, of end cap 50 . Insert stubs 67 a to 67 d and retention stub 68 are integrally molded with a planar wall portion 61 , and in the completed assembly 1 seal off the individual ink supply channels 20 a - 20 d from one another, to prevent cross-migration of ink among them. Wall 77 of the retention stub 68 abuts the shim 25 in the same way as described above. A sealant or adhesive is preferably used with end cap 60 in the same way (and for the same purpose) as described above in respect of end cap 50 .
Whereas end cap 50 enables connection of ink supply hoses to the printhead assembly 1 , end cap 60 has no tubular stubs on exterior face 62 of planar wall portion 61 . Instead, four tortuous grooves 65 a to 65 d are formed on exterior face 62 , and terminate at holes 66 a to 66 d . respectively, extending through wall portion 61 . Each one of holes 66 a to 66 d opens into a respective one of the channels 20 a to 20 d so that when the cap 60 is in place on the profile 10 , each one of the grooves 65 a to 65 d is in fluid communication with a respective one of the channels 20 a to 20 d . The grooves 65 a - 65 d permit bleeding-off of air during priming of the printhead assembly 1 with ink, as holes 66 a - 66 d permit air expulsion from the ink supply channels 20 a - 20 d of support profile 10 via grooves 65 a - 65 d. Grooves 65 a - 65 d are capped under a translucent plastic film 69 bonded to outer face 62 . Translucent plastic film 69 thus also serves the purpose of allowing visual confirmation that the ink supply channels 20 a - 20 d of profile 10 are properly primed. For charging the ink supply channels 20 a - 20 d with ink, film 69 is folded back (as shown in FIG. 15 ) to partially uncover grooves 65 a - 65 d . so that displaced air may bleed out as ink enters the grooves 65 a - 65 d through holes 66 a - 66 d . When ink is visible behind film 69 in each groove 65 a - 65 d . film 69 is folded towards face 62 and bonded against face 62 to sealingly cover face 62 and so cap-off grooves 65 a - 65 d and isolate them from one another.
Referring to FIG. 17 (and see also FIGS. 3 and 4 ), the printed circuit board (PCB) 11 locates between edges 24 formed on profile 10 , and is secured by screw fasteners 23 which engage with the serrations in elongate channel 22 of support profile 10 . The PCB 11 contains three surface mounted halftoning chips 73 , a data connector 74 , printhead power and ground busbars 75 and decoupling capacitors 76 . Side walls 16 , 17 of support profile 10 are rounded near the edges 24 to avoid damage to the TAB films 9 when these are wound about profile 10 . The electronic components 73 and 76 are specific to the use of MEMJET chips as the printhead segments 4 , and would of course, if other another printhead technology were to be used, be substituted with other components as necessitated by that technology.
The shield plate 5 illustrated in FIG. 1 , which is a thin sheet of stainless steel, is bonded with sealant such as a silicon sealant onto the printhead segment carriers 8 . The shield plate 5 shields the TAB films 9 and the printhead segments 4 from physical damage and also serves to provide an airtight seal around the printhead segments 4 when the assembly 1 is capped during idle periods.
The multi-part layout of the printhead assembly 1 that has been described in detail above has the advantage that the printhead segment carriers 8 , which interface directly with the printhead segments 4 and which must therefore be manufactured with very small tolerances, are separate from other parts, including particularly the main support frame (profile 10 ) which may therefore be less tightly toleranced. As noted above, the printhead segment carriers 8 are precision injection micro-moldings. Moldings of the required size and complexity are obtainable using existing micromolding technology and plastics materials such as ABS, for example. Tolerances of +/−10 microns on specified dimensions are achievable including the ink supply grooves 96 a - 96 d . and their relative location with respect to the recess 90 in which the printhead segments 4 are received. Such tolerances are suitable for this application. Other material selection criteria are thermal stability and compatibility with other materials to be used in the assembly 1 , such as inks and sealants. The profile 10 is preferably an aluminum alloy extrusion. Tolerances specified at +/−100 microns have been found suitable for such extrusions, and are achievable as well.
FIGS. 19, 20 and 21 are schematic representations only, intended to provide an understanding of the construction of an injection molding die used in the manufacture of a printhead segment carrier 8 . A multi-part die 100 is used, having a fixed base die part 104 , which in use defines the face 82 , recess 90 and slots 96 a to 96 d of the carrier 8 , and a multi-part upper die part 102 . The upper die part 102 is closed against the base part 104 for molding, and includes a part 101 with multiple fingers 101 a which in use form the galleries 92 b (including galleries 92 b ′) and parts 106 which are fixed relative to part 101 . Also included in the upper part 102 are die parts 103 which are movable relative to the part 101 and which have fingers 103 a to form the remaining galleries 92 a . 92 c and 92 d. Parts 103 seat against parts 106 when molding is underway. Spaces between the fingers 101 a and 103 a correspond to the walls 97 . In use of the die 100 , terminal tips of the fingers 101 a and 103 a close against blades 105 which in use form the ink supply slots 96 a - 96 d of carrier 8 and which are mounted to male base 104 to be detachable and replaceable when necessary. Base die part 104 also has inserts 104 a which in use form the pickup slots 87 . Because zero draft is preferred on the stepped end faces 83 in this application, the die 100 also has two movable end pieces (not shown, for clarity) which in use of the die 100 are movable generally axially to close against the upper die part 102 and which are shaped to define the end faces 84 ′, 85 ′ and 86 ′ of carrier 8 . FIG. 21 shows a schematic transverse cross-section of the mold 100 when closed, with areas in black corresponding to the carrier 8 being molded.
As was mentioned above, the two opposite end portions of the larger quarter cylinder section of carrier 8 incorporate two ink supply chambers 99 c and 99 d (see FIG. 12 ) to provide ink to the ink supply slots 96 c and 96 d in that region of the carrier 8 . These chambers 99 c and 99 d and associated communication holes 113 and 114 in parallel walls 97 that lead into the neighbouring galleries 92 c and 92 d . are formed in an operation subsequent to molding, by laser cutting openings of the required shape in the end walls 84 and the neighbouring inner parallel walls 97 from each end. The openings cut in end walls 84 are only necessary so as to access the inner walls 97 , and are therefore subsequently permanently plugged using appropriately shaped plugs 115 as shown in FIG. 6 .
Extrusions usable for profile 10 can be produced in continuous lengths and precision cut to the length required. The particular support profile 10 illustrated is 15.4 mm×25.4 mm in section and about 240 mm in length. These dimensions, together with the layout and arrangement of the walls 16 and 17 and internal webs 14 a to 14 c . have been found suitable to ensure adequate ink supply to eleven (11) MEMJET printhead segments 4 carried in the support profile to achieve four-color printing at 120 pages per minute (ppm). Support profiles with larger cross-sectional dimensions can be employed for very long printhead assemblies and/or for extremely high-speed printing where greater volumes of ink are required. Longer support profiles may of course be used, but are likely to require cross-bracing and location into a more rigid chassis to avoid alignment problems of individual printhead segments, for example in the case of a wide format printer of 54″ (1372 mm) or more.
An important step in manufacturing (and assembling) the assembly 1 is achieving the necessary, very high level of precision in relative positioning of the printhead segments 4 , and here too the construction of the assembly 1 as described above is advantageous. A suitable manufacturing sequence that ensures such high relative positioning of printheads on the support profile will now be described.
After manufacture and successful testing of an individual printhead segment 4 , its associated TAB film 9 is bumped and then bonded to bond pads along an edge of the printhead segment 4 . That is, the TAB film is physically secured to segment 4 and the necessary electrical connections are made. The terms “bumped” and “bonded” will be familiar to persons skilled in the arts where TAB films are used. The printhead carrier 8 is then primed with adhesive on all those surfaces facing into recess 90 that mate and must seal with the printhead segment 4 , see FIG. 11 a . i.e. along the length of the radially-inner edges of walls 95 , 108 and 111 , the face of formation 112 and on inner faces of walls 84 . The printhead segment 4 is then secured in place in recess 90 with its TAB film 9 attached. Extremely accurate alignment of the printhead segment 4 within recess 90 of printhead segment carrier 8 is not necessarily required (but is preferred), because relative alignment of all segments 4 at the support profile 10 is carried out later, as is described below. The assembly of the printhead segment 4 , printhead segment carrier 8 and TAB film 9 is preferably tested at this point for correct operation using ink or water, before being positioned for placement in the slot 21 of support profile 10 .
The support profile 10 is accurately cut to length (where it has been manufactured in a length longer than that required, for example by extrusion), faced and cleaned to enable good mating with the end caps 50 and 60 .
A glue wheel is run the entire length of semi-circular slot 21 , priming the terminal edges 14 a ′, 14 b ′, 14 c ′ of webs 14 a - 14 c and edges 16 ′, 17 ′ of profile side walls 16 , 17 with adhesive that will bond the sealing shim 25 into place in slot 21 once sealing shim 25 is placed into it with preset distance from its terminal ends (+/−10 microns). The shim 25 is snap-fitted into place at edges 16 ′, 17 ′ and the glue is allowed to set. Next, end caps 50 and 60 are bonded into place whereby (ink channel sealing) insert stubs 57 a - 57 d and 67 a - 67 d are received in ink channels 20 a - 20 d of profile 10 , and faces 71 and 77 of retention stubs 58 and 68 , respectively, lie on shim 25 . This sub-assembly provides a chassis in which to successively place, align and secure further sub-assemblies (hereinafter called “carrier subassemblies”) each consisting of a printhead segment carrier 8 with its respective printhead segment 4 and TAB film 9 already secured in place thereon.
A first carrier sub-assembly is primed with glue on the back face 91 of its printhead segment carrier 8 . At least the edges of walls 95 and 86 are primed. A glue wheel, running lengthwise, is preferably used in this operation. After priming with glue, the carrier sub-assembly is picked up by a manipulator arm engaging into pick-up slots 87 on front face 82 of carrier 8 and placed next to the stub 58 of end cap 50 (or the stub 68 of cap 60 ) at one end of slot 21 in profile 10 . The glue employed is of slow-setting or heat-activated type, thereby to allow a small level of positional manipulation of each carrier subassembly, lengthwise in the slot 21 , before final setting of the glue. With the first carrier subassembly finally secured to the shim 25 within the slot 21 , a second carrier sub-assembly is then picked up, primed with glue as above, and placed in a 180-degree-rotated position (as described above, and as may be seen in FIG. 3 ) next to the first carrier sub-assembly onto shim 25 and within the slot 21 . The second carrier sub-assembly is then positioned lengthwise so that there is correct lengthwise relative positioning of its printhead segment 4 and the segment 4 of the previously-placed segment 4 , as determined using suitable fiducial marks (not shown) on the exposed front surface 44 of each of the printhead segments 4 . That is, lengthwise alignment is carried out between successive printhead segments 4 , even though it is the printhead segment carrier 8 that is actually manipulated. This relative alignment is carried out to such (sub-micron) accuracy as is required to match the printing resolution capability of the printhead segments 4 . Finally, the bonding of the second carrier sub-assembly to shim 25 is completed. The above process is then repeated with further carrier sub-assemblies being successively positioned, aligned, and bonded into place, until all carrier subassemblies are in position within the slot 21 and bonded in their correct positions.
The shield plate 5 has a thin film of silicon sealant applied to its underside and is mated to the printhead segment carriers 8 and TAB films 9 along the entire length of the printhead assembly 1 . By suitable choice of adhesive properties of the silicon sealant, the shield plate 5 can be made removable to enable access to the printhead segment carriers 8 , printhead segments 4 and TAB films 9 for servicing and/or exchange.
A sub-assembly of PCB 11 and printhead control and ancillary components 73 to 76 is secured to profile 10 using four screws 23 . The TAB films 9 are wrapped around the exterior walls 16 , 17 of profile 10 and are bumped and bonded (Le. physically and electrically connected) to the PCB 11 . See FIG. 17 .
Finally, the completed assembly 1 is connected at the ink inlet stubs 55 a - d of end cap 50 to suitable ink supplies, primed as described above and sealed using sealing film 69 of end cap 60 . Power and signal connections are completed and the inkjet printhead assembly 1 is ready for final testing and subsequent use.
It will be apparent to persons skilled in the art that many variations of the above-described assembly and components are possible. For example, FIG. 18 shows a shim 125 that is substantially the same as shim 25 , including having openings 126 and 126 ′ corresponding to the openings 26 and 26 ′ in shim 25 , save for longitudinally extending rim webs 128 which, when the shim 125 is mounted to a support profile 110 , abut in surface-engaging manner against the outside of the terminal ends of side walls 116 , 117 of profile 110 instead of being snap-fittingly received between them as is the case with shim 25 . This arrangement permits wider tolerances to be used in the manufacture of the support profile 110 without compromising the mating capability of the shim 125 and the profile 110 .
In yet another possible arrangement, the shim 25 could be eliminated entirely, with the printhead segment carriers 8 then bearing and sealing directly on the edges 14 a ′- 14 c ′ and 16 ′, 17 ′ of the webs 14 a - 14 c and side walls 16 , 17 at slot 21 of support profile 10 . It will be appreciated by persons skilled in the art that still further variations and modifications may be made without departing from the scope of the invention. The embodiments of the present invention as described above are in no sense intended to be restrictive. | An inkjet printhead assembly includes: a support structure having a recess, the recess having a wall defining a plurality of ink supply apertures; and a plurality of print modules received in the recess in a neighboring arrangement. Each print module includes: a printhead chip carrier having a plurality of convergent ink galleries, each ink gallery receiving ink from an ink supply aperture; and a single printhead chip mounted on the printhead chip carrier, the printhead chip receiving ink from the plurality of convergent ink galleries. | 1 |
FIELD OF INVENTION
[0001] This invention discloses the monitoring and controlling of oxidation reduction potential (ORP or redox) during the fermentation process for the production of ethanol. This novel process is intended for the burgeoning fuel ethanol industry, where both measurement and control of oxidation reduction potential is not currently practiced. With tighter controls on ORP, the new ethanol process will deliver higher yields, shorter fermentation times, and decreased byproduct formation.
[0002] Ethanol has become an important fuel in today's economy and is expected to become more important in the future. Ethanol can be made from a variety of grains and sugar sources, including but not limited to corn, sorghum, wheat, barley, molasses, cane syrup, potatoes, and whey. Two major (dry mill and wet mill) processes are used to manufacture ethanol, which include some common steps, such as milling, liquefaction and fermentation. This invention will primarily focus on controlling ethanol fermentation, by measuring and controlling the oxidation reduction potential of the corn mash.
[0003] An economic study performed by Kansas State University (Coltrain, David; “Economics of Ethanol”; Risk and Profit 2001 Conference; Holiday Inn of Manhattan, Kans.; Aug. 16-17, 2001; slide 26) showed that 50% to 70% of the total production cost is attributed to the cost of grain usage. An important index of manufacturing economics is the ethanol yield, which is typically measured as gallons of anhydrous ethanol produced per bushel of grain. Under current practice, this yield ranges from 2.5 to 2.8 gallons per bushel. A yield improvement of 10% would have an enormous impact on the profitability of an industrial fuel ethanol producer.
[0004] Major yield losses are attributed to unconverted starch in the fermentor and unwanted byproduct formation. The major byproduct formed in the ethanol fermentation process is glycerol, as indicated in the article by S. Alfenore et al.; “Aeration strategy: a need for very high ethanol performance in Saccharomyces Cerevisiae fed-batch process”; Applied Microbiology and Biotechnology (2004); Volume 63; pages 537-542. Typical results are shown below in Table One:
TABLE ONE Typical Byproducts of Ethanol Fermentation Components Units Concentration Ethanol g/l 131 Glycerol g/l 12.2 Acetate g/l 0.51 Succinate g/l 0.74
[0005] Industrial HPLC (High Performance Liquid Chromotography) analysis of products leaving the ethanol fermentor confirms, as well, that glycerol is the major byproduct. Glycerol is soluble in water and leaves the fuel alcohol plant as Distiller's Dried Grains and Solubles (DDGS). Attempts to recover glycerol from the thin stillage stream, such as shown in U.S. Pat. No. 5,177,008 by Kampen have not been commercially successful.
[0006] Glycerol formation in fermentation by the yeast Saccharomyces Cerivisiae has been studied for a long time. The earliest manufacture of glycerol via fermentation was practiced during World War I by the German biochemist Carl Neuberg which enabled Germany to produce more than a thousand tonnes per month of glycerol by addition of a bi-sulfite solution to the fermenting mash.
[0007] Later biochemical studies verified that glycerol is produced by the yeast Saccharomyces Cerivisiae as a cellular redox balance. Strong reductants such as sulfite and bi-sulfite would encourage more production of glycerol. Other reductants, such as ammonia, would also favor glycerol formation. Some reductants that can be found in industry:
Sulfites, Bi-sulfites and Sulfur Dioxide Ammonia Hydrazine Reducing gases such as hydrogen and carbon monoxide
[0012] Naturally, this list does not include all reductants. However, it should be noted that ammonia is used in the ethanol industry to elevate the corn mash pH prior to liquefaction. Additionally, sulfite is used in the wet mill ethanol process for grain separation.
[0013] Substitution of ammonia with a more oxidizing caustic would raise the oxidation reduction potential (ORP) and lead to lower glycerol formation. Similarly, sulfite replacement or oxidation to sulfate would raise ORP and minimize glycerol production. Another method of increasing ORP would be to add an oxidant, such as:
Hydrogen peroxide Ozone Dihalides (Chlorine, Bromine, Iodine.) Chlorine Dioxide Potassium Permaganate Air or oxygen sparging
[0020] Glycerol formation decreased from 0.042 grams per gram of glucose to 0.010 grams per gram of glycose, when more oxidizing conditions were present under full aeration consistent with the data supplied by Alfenore et al. Raising the oxidation reduction potential also has the beneficial effect of improving the average ethanol productivity from 2.6 grams of ethanol per liter per hour to 3.3 grams of ethanol per liter per hour.
[0021] However, under these full aeration conditions, ethanol yield decreased from 0.46 grams of ethanol to 0.43 grams of ethanol for the full aeration case. This decrease in yield can be attributed to the increase in biomass (i.e. yeast) concentration or aerobic yeast respiration. It should also be noted that ORP was not measured in this study, but instead dissolved oxygen of the fermentation broth was monitored. Aqueous ammonia was also added for pH control, which will lower the ORP.
[0022] It is clear from a study of the literature that fully oxidizing conditions would not lead to optimal ethanol yields. Likewise, a strong reducing environment, such as is present with the addition of bi-sulfite, ethanol formation would be discouraged and glycerol formation would be encouraged.
[0023] It is the intent of this invention to show that an optimal level of oxidation reduction potential would increase ethanol yield, decrease glycerol formation and reduce fermentation time than the current practice.
[0024] Various prior art patents have been available to describe ethanol fermentation processes, and the like. For example, the United States patent to Wendt, U.S. Pat. No. 3,123,475, describes a typical sequential batch ethanol fermentation process, which is employed widely throughout the fuel alcohol industry. There is no mention of oxidation-reduction potential in this patent.
[0025] One of the more pertinent examples of prior art, specifically U.S. Pat. No. 3,384,553 used dissolved oxygen meters to monitor the yeast ( Saccharomyces Cerevisiae ) formation under aerobic (not anaerobic ethanol producing) conditions. Dissolved oxygen probes suffer from fouling and require constant calibration. Additionally, under very low oxygen concentrations this measurement is highly inaccurate and unreliable.
[0026] In U.S. Pat. No. 4,046,921, there is no mention of yeast, and certainly not, Saccharomyces Cerevisiae , or Oxidation Reduction Potential. The patent is directed towards cultivating microorganisms by a fluidized bed.
[0027] Chelle discloses in U.S. Pat. No. 4,204,042 a method to agitate and gasify a fermentor under aerobic conditions. There is no mention of Oxidation Reduction Potential or yeast.
[0028] In U.S. Pat. No. 4,346,113, Faust et al claim the merits of feeding an exact amount of oxygen bearing gas to the fermentor to reach the optimal production of ethanol. There is no further discussion on what is meant by the phrase “optimal production”. The yeast Saccharomyces Cerevisiae was used in one of the examples. Dissolved oxygen concentration was measured at a low level (0-1 ppm), but no explanation was given when the dissolved oxygen was measured. It should also be noted that there is no mention of measuring or controlling oxidation reduction potential.
[0029] Hopkins in U.S. Pat. No.4,468,455 directs our attention to an online dissolved oxygen probe with cell culture control of an aerobic micro-organism. Yeast is mentioned in the patent, but ethanol is not. Redox potential probe is cited in claim 6(c), but no values are given, measured or controlled.
[0030] In U.S. Pat. No. 4,477,569, Schneider et al discloses that fermentation of pentose by a selected yeast strain is benefited from air addition, as shown in the corresponding Table One. There is no mention of either the industrial yeast Saccharomyces Cerevisiae nor measuring oxidation reduction potential in the fermentation broth.
[0031] Swartz, in U.S. Pat. No. 5,633,165, discloses the use of online redox (oxidation reduction potential) measurements in a bacterial fermentation in FIGS. 27B, 28B, 29B, 30B, 31B and 32B under aerobic conditions. Ethanol producing yeast are not cited in the patent. However, it is interesting to note on some figures that the agitation rate was lowered to check the dissolved oxygen probe zero.
[0032] It should be remembered that all prior art does not explain the role that oxidation reduction potential plays in ethanol fermentation. No attempt was made in the prior art to define what constitutes the optimal redox level for ethanol non-obvious.
SUMMARY OF THE INVENTION
[0033] In accordance with this invention, there is provided a process to monitor and control oxidation reduction potential to improve the overall ethanol yield, reduce glycerol formation, and decrease fermentation time. Optimal oxidation reduction potential will be found in the range of −200 mV to +350 mV where the yeast Saccharomyces Cerevisiaie is known to survive. The novel process is directed to the fuel alcohol industry, but could also be used in the distilled spirits, beer and wine-making industries, as well.
[0034] It is, therefore, the principal object of this invention to provide means for achieving oxidation reduction potential, and its control, for use in the fermentation such as the production of ethanol, whether for industrial, beverage, or for any usage and application.
[0035] Still another object of this invention is to provide a process that monitors and controls the oxidation reduction potential for the purpose of improving fermentation such as but not limited to ethanol.
[0036] Another object of this invention is to provide a process to reduce glycerol formation, thereby decreasing the fermentation time such as for the production of ethanol, but not limited to it.
[0037] These and other objects may become more apparent to those skilled in the art upon review of the summary of the invention as provided herein, and upon undertaking a study of the description of its preferred embodiment, in view of the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0038] In referring to the drawings,
[0039] FIG. 1 provides a chart of ethanol fermentation and the typical oxidation potential curve raised during ethanol fermentation;
[0040] FIG. 2 provides a schematic view of the fermentor used in conjunction with the process of this invention; and
[0041] FIG. 3 shows a fermentor feed oxidation vessel, at its various associated operative accessories.
BRIEF DESCRIPTION OF INVENTION
[0042] Oxidation reduction potential, which is typically measured in millivolts, is the tendency of a chemical species to gain or lose electrons by reaction. Oxidation is the loss of electrons by an atom, molecule or ion. When a substance is oxidized, its oxidation state is increased. Reduction is the net gain of electrons and when the substance is reduced, its oxidation state is decreased. These oxidation-reduction reactions follow the well known Nernst equation.
[0043] Oxidation reduction potential can be measured by two methods. The first method employs a titration with either a known concentration of an oxidant or reductant to an endpoint color, similar to pH titration. An example of this titration would be measuring a reductant by titrating with potassium permanganate (KMnO 4 ), which forms a deep blue-purple solution, when dissolved in water. The endpoint of the titration is established when the dark color changes to a pink solution. Another example of an ORP titration is with a soluble starch solution and potassium iodide and iodine mixture. Since there is a known concentration of reductant or oxidant, the ORP can be determined. These analytical titrations are prone to human error and are quite laborious. Additionally, as with any offline measurement, there is a delay involved.
[0044] The preferred method utilizes an online oxidation reduction potential measurement. The principle behind the ORP measurement utilizing an inert platinum or gold electrode, which due to its inherently low resistance, will give up electrons from an oxidant or accept electrons from a reductant. The ORP electrode will continue to give up or accept electrons until an electrical potential is developed which matches the oxidation reduction potential of the solution. The reference electrode used for ORP measurement is typically made from the same silver-silver chloride electrode as pH measurements. Usually, the pH electrode can measure ORP, as well, such as the Rosemount Model 389 pH/ORP sensor or the Yokogawa Model PH20 and FU20. Likewise, the transmitters are typically combination pH and ORP such as the Rosemount Model 1055 Analyzer or the Yokogawa Model PH402G pH/ORP converter.
[0045] By utilizing online measurements, the oxidation reduction potential of ethanol fermentation can be adjusted by one of these methods, but is not limited to these methods
1. Oxidant addition (such as air or oxygen sparging, peroxide etc). 2. Reductant substitution (such as ammonia with caustic) 3. Reductant elimination (such as oxidation of sulfite)
[0049] Currently, the range of the yeast Saccharomyces Cerevisiae activity is between −200 millivolts and +350 millivolts, according to Kukec et al. in the article entitled “The Role of On-Line Redox Potential Measurement in Sauvignon Blanc Fermentation”; Food Technology and Biotechnology ; Volume 40 (2002); Number 1; page 50. Above +350 millivolts, oxygen acts toxically and inhibitory and below −200 millivolts, the concentration of dissolved oxygen is too low for normal life conditions of yeast. However, this range is too large for process control, and further experiments should determine the oxidation reduction potential which is optimal for ethanol yield.
[0050] Data taken at SIUE's Corn to Ethanol laboratory clearly shows that the addition of a reductant (sodium bi-sulfite) in the quantity of 0.14 grams per liter of fermentor liquid leads to the following results:
1. Higher glycerol to ethanol ratios (gm glycerol per 100 gm ethanol)
10.36 for the corn mash without bi-sulfite 11.42 for the corn mash with bi-sulfite
2. Lower yeast viability counts averaged during the fermentation
468 MM per ml in the corn mash without bi-sulfite 332 MM per ml in the corn mash with bi-sulfite
3. Higher residual starch content
2.78 equivalence in the corn mash without bi-sulfite 3.78 equivalence in the corn mash with bi-sulfite
4. Slower fermentation times by 5-7% with addition of bi-sulfite.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0061] FIG. 1 shows a typical oxidation reduction potential curve during ethanol fermentation. Although the fermentation was conducted under low temperature conditions, the trends are very clear. Redox decreases from an initial positive oxidizing and aerobic (˜+225 mv) value to a negative (˜−100 mv) anaerobic value, as shown on the left hand scale. Meanwhile, the biomass concentration clearly increases from ˜0.3 grams per liter to a maximum value of 7.2 grams per liter, as shown on the right hand scale, while the redox decreases in value. Similarly, the reducing sugar concentration decreases from 250 grams per liter to zero and parallels the oxidation reduction potential, but with a lag in time. During the same period, ethanol concentration increases from zero to a maximum of ˜90 mg/liter, as shown on the left hand scale. Meanwhile, the concentration of glycerol increases from zero to 7 grams per liter, as shown on the right hand scale. It should be noted that all the measurements, except oxidation reduction potential are performed typically by High Performance Liquid Chromatography (HPLC), while, in industrial practice, only ORP can be measured on-line.
[0062] FIG. 2 displays air sparging directly into the fermentor (labeled number 2 ) in order to raise the oxidation reduction potential. Initially, propagated yeast normally enters the top of the fermentor through the pipe numbered 1 . As drawn, this feed is shown on the side, but it can enter on the top of the fermentor. Once the yeast enters the fermentor and is filled to a certain level, the yeast solution is closed and the liquefied mash now enters the fermentor, usually in pipe 1 , but this feed could enter through a different nozzle location. Upon reaching a certain desired oxidation reduction potential, as measured in either sensor labeled 5 A or 5 B, high pressure air in pipe numbered 3 , enters through the control valve numbered 4 . It should be appreciated that an air flow meter in pipe 6 may be placed in this pipe in order to monitor the amount of air flowing to the sparger labeled as part of the equipment numbered 7 . Typically, the fermentor contains an agitator with a motor (number 8 A) and impellors (number 8 B) to thoroughly mix the contents of the fermentor. The fermentor is recirculated through the bottom of the fermentor through pipe numbered 9 and pump 10 . During fermentation, all the liquid is sent through pipe numbered 11 and none of the fluid through pipe numbered 12 . The shell and tube exchanger numbered 13 cools the fermentation liquor to remove the heat of fermentation. It should be appreciated that although a shell and tube exchanger is shown, a spiral exchanger or plate and frame exchanger could be used. Typically, chilled water is used to maintain the fermentation temperature. The chilled liquid then enters back into the fermentor through pipe 15 . Once fermentation is completed, the beer exits through pipe numbered 12 , and usually, no beer enters the pipe numbered 11 .
[0063] FIG. 3 shows ambient air being admitted to the system through pipe numbered 1 and then discharged by fan numbered 2 into a gas duct numbered 3 , which is connected near the bottom of a gas-liquid contacting device, which is labeled number 4 . Liquefied corn mash enters near the top at location numbered 5 of the contacting device, which can be an open venturi type contactor or a trayed column or other known contacting device, used in the industry. The air exits the contacting device, through duct numbered 6 and then can be sent to the volatile organic compounds burner, for example. This gas-liquid contactor is properly instrumented with level, temperature or pressure monitors, which are shown by numbers 7 and numbers 8 . The aerated liquid exits the contactor through pipe numbered 9 and is delivered to the fermentor via pump labeled 10 through pipeline 12 . Oxidation Reduction Potential monitor numbered 11 can be controlled by adjusting either the speed or inlet guide vane of air blower numbered 2 .
EMBODIMENTS OF THE INVENTION
[0064] One embodiment is to eliminate reductants such as ammonia, urea or sulfur dioxide from entering the corn mash. Ammonia and urea can be replaced with caustic. The increased ethanol sales through reductant elimination is expected to more than offset any increased chemical usage cost. The projected profit increase can be as much as 3 Million for a 25 Million Gallon per year plant. However, there is concern that the replacement of ammonia ions with sodium ions may have an adverse impact on the yeast. Ingledew reports in page 52 of The Alcohol Textbook that sodium limitations of 500 ppmw should be placed on the yeast Saccharomyces Cerevisiae . Curran and Montville writing in “Bicarbonate inhibition of Saccharomyces Cerevisiae and Hansenula wingei growth in apple juice” in the International Journal of Food Microbiology in February 1989, pages 1-9 that as much as 5500 ppmw.
[0065] Another embodiment is shown in FIG. 2 , where air or oxygen is added directly to the fermentor. This approach will require more capital than the substitution of caustic for ammonia or urea. Sparging alleviates the detrimental effect of sodium on the yeast. Additionally, oxidation reduction potential, since it is measured in the fermentor can be controlled to almost any level by simply adjusting the amount of air (oxygen) going to the fermentor. Direct feedback of the redox potential is then accomplished.
[0066] An additional benefit is that the yeast propagation tank can be eliminated, since a fully oxidizing environment can be attained in the fermentor. There are two problems encountered with this approach. First, air addition directly into the fermentor will dilute the carbon dioxide leaving the fermentor. In some ethanol plants, the carbon dioxide byproduct is an attractive revenue source. Air dilution may render the carbon dioxide stream unrecoverable. Secondly, air bubbling is not an efficient method of contacting liquid with gas streams. Considerable energy is wasted in this approach.
[0067] An alternate method of efficiently contacting air and liquid is through a lower pressure contacting device. As discussed earlier, there are many gas-liquid contacting devices that are practiced by one skilled in the art. Instead of higher pressure air, as shown in FIG. 2 , air is supplied via a blower, which can be modulated either by an inlet guide vane or a variable speed drive. These blowers consume a lower amount of energy. As in FIG. 2 , the yeast propagation tank can be eliminated. Since the broth is aerated prior to the fermentor, the carbon dioxide product can be recovered, thereby retaining the associated revenues. However, there is a lag between ORP in the fermentor, and the ORP in the feed stream. In addition, the required capital for this invention is considerably more than either two previously mentioned options, since there is additional equipment, instrumentation and controls. Site economics will dictate the most attractive embodiment.
[0068] In all cases, the downstream equipment from the fermentors is assumed to be sized for the increased ethanol concentration. Otherwise, there would be a need to debottleneck the distillation and dehydration equipment and possibly the storage tanks to allow the full economic benefit of this invention to be realized.
[0069] Variations or modifications to the subject matter of this invention may occur to those skilled in the art upon review of the invention as described herein. Such variations, if within the spirit of this development, are intended to be encompassed within the scope of the invention as defined. The description of the preferred embodiments, specific example set forth, and all as shown in the drawings, are set forth for illustrative purposes only. | A process to improve ethanol yield, decrease fermentation time and reduce byproduct formation by monitoring and controlling oxidation reduction potential (redox) of the fermentor is disclosed. | 2 |
BACKGROUND OF THE INVENTION
The present invention relates to PC cards used to provide additional circuitry and external connections for computers and other electrical devices. PC cards (cards with printed circuits) are commonly made in accordance with PCMCIA (Personal Computer Memory Card International Association) specifications which define, among other things, the dimensions of such card. One of the critical dimensions is the maximum thickness of the cards, the maximum thickness being 5 mm for the common Type II PC cards, which permits the cards to be inserted into a standard receiving slot of an electrical device such as a laptop computer. Such PC cards normally include a housing having top and bottom sheet metal cover parts (which may be integrally joined at one end), a printed circuit board holding circuit components and contained within the housing, and a front connector at a front end of the card. The front connector mates with a device connector at the front end of the insertion slot to connect to circuitry on the circuit board. The housing is intended to provide shielding, or screening, against electromagnetic radiation passing into or out of the PC card.
Circuitry, including circuit components (e.g. integrated circuits, capacitors, conductors, and resistors, which all affect currents passing therethrough) sometimes require electromagnetic isolation from other circuitry to prevent cross coupling. Such shielding or screening must remain intact after mechanical flexing of the PC card, which normally occurs in use. PCMCIA specifications describe a "torque test" and "bend test" which cards must survive to simulate this phenomenon. One way of providing screening is to employ a number of shielding inner covers that fit over interfering circuitry and which are coupled to a grounding trace on the circuit board. Such covers are unreliable due to their resistance to flexing and a consequent risk of damage to the circuit board during flexing of the PC card.
Applicants have tried to provide internal shielding by using conductive elastomer to form a wall around the circuitry to be screened. Such elastomer wall is sandwiched between a grounding trace on the circuit board and a cover part, and is compressed between them. In this way, the elastomer wall and the cover part form an effective screen for the circuitry lying within the wall. A problem with this construction is that it does not provide sufficient compression force between the cover part and circuit board to ensure reliable low resistance contact, without bulging out the cover part. The cover parts are typically formed of thin sheet metal such as stainless steel, to limit the overall thickness of the card while leaving space for the circuit board and the circuit components. As a result, even a low force can result in the cover outer surfaces becoming convex so the cover bulges. Bulging covers can result in the card thickness increasing beyond the specified maximum thickness, as well as resulting in a card appearance which is unsightly and which suggests damage. The present invention seeks to provide a solution to the above problem.
SUMMARY OF THE INVENTION
In accordance with one embodiment of the invention, a PC card is provided with enhanced internal shielding. The PC card includes a housing having top and bottom sheet metal cover parts, a printed circuit board mounted in the housing, and at least one flexible electrically conducted internal shield. The internal shield lies between the circuit board and one of the cover parts, and is held in place by an electrically conductive adhesive to one, or both, of the cover and the corresponding trace on the circuit board.
The use of a conductive adhesive ensures that there is reliable low resistance electrical connection between the internal shield and the grounding trace on the board, and preferably also the cover, without requiring compressive force on the conductive shield or at least without requiring a sufficient magnitude of such force as would noticeably distort the thin metallic cover parts. The construction also permits the shield to act as an accurate spacer to maintain a more constant thickness of the PC card and thereby resist flexing of the PC card without damage to the circuit board.
The adhesive employed on at least one side of the internal shield may be releasable to permit opening of the PC card without damage to the circuit board or the internal shield. The adhesive employed on the opposite side of the shield may be a permanent nonreleaseable type to maintain securement of the shield.
Each internal shield may be formed from a conductive elastomer which may contain, for example, particles of silver to render it conductive. Each shield may be molded to define walls providing one or more enclosures for components on the board.
A plate-like shielding device preferably covers the top of the internal shield. The shielding device preferably includes a metal foil and a layer of a conductive adhesive bonding the foil to the upper face of the internal shield, with the foil extending over the entire shielding volume enclosed by the internal shield. The foil is also preferably bonded to the upper cover part.
A method of manufacturing a PC card includes securing at least one flexible conductive internal shield to a ground trace on the circuit board and/or one of the sheet metal cover parts, by means of a conductive adhesive when installing the board in the housing. The method may include the step of securing a similar second flexible conductive shield to the other cover part by means of a conductive adhesive, so the second shield is disposed between the board and the other cover part.
The method may include the additional step of providing conductive adhesive on both sides of a metal foil to form a shielding part. The internal shield is attached to the cover by attaching one adhesive layer on the foil to one of the cover parts and the other adhesive layer on the foil to the conductive internal shield. In a particularly advantageous manufacturing environment, the method may include the additional step of releasably attaching the shields on a carrier liner strip from which they are transferred to a cover or circuit board during manufacture.
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 an exploded isometric view of a PC card constructed in accordance with the invention.
FIG. 2 is a partial exploded bottom view of a refinement of the PC card of FIG. 1.
FIG. 3 is an enlarged sectional view of the refinement of FIG. 2, and also showing the parts assembled on a circuit board.
FIG. 4 is an isometric view of a circuit board with a conductive shield of another embodiment of the invention thereon.
FIG. 5 shows a carrier liner strip provided with internal shields for use in the manufacture of PC cards.
FIG. 6 is a sectional view of a portion of a circuit board, a top cover part, and an internal shield with a shielding device at the top, constructed in accordance with another embodiment of the invention.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows a PC card (card with printed circuit board) comprising a two-part housing 10 and a printed circuit board 14. The housing includes top and bottom cover halves or cover parts 16, 17 that are each stamped from stainless steel sheet metal. Upper and lower gaps 21, 23 lie between the circuit board faces and the cover parts. A pair of molded internal shields 18, 20 are provided, in the form of rectangular walled enclosures, with each shield being shown attached to a corresponding one of the cover parts. Each internal shield is formed from an electrically conductive elastomer, for example, CHO-SEAL of 1310 Parker Hannifin Plc. This material contains silver plated particles and provides excellent electrical conductivity. Each internal shield is secured to one of the covers by means of an electrically conductive adhesive, such as CHO-BOND 1030 of Parker Hannifin Plc. The adhesive cures on exposure to air to form a nonreleasable joint.
A front end connector 22 is mounted at the front end of the circuit board. Circuit components 24, 26 are mounted on the circuit board and are connected to signal traces 15, 18 on the board. The components 24 form circuitry that is to be shieded to prevent radiation or reception of interfering electromagnetic energy to other circuitry on the board, such as circuitry that includes circuit components 26. To do this, a shielding volume 23 is defined in the upper gap 21, which extends from an area on the circuit board upper face 25 and upwardly beyond the board face, to substantially the inner face 27 of the upper cover part. A similar shielded volume 29 lies in the lower gap 23 between the board lower face 31 and substantially the inner face 33 of the lower cover part.
The circuit board 14 has a grounding trace 28 which is arranged to make contact with the internal shield 18 when the PC card is assembled. To assemble the PC card, the board is placed in the bottom cover part 17 and the top cover part 16 is then snapped onto the bottom cover part. Such snap attachment is made by cooperating sidewalls 30, 32, 34, 36 of the cover parts. A similar grounding trace may be provided on the lower side of the board for contact with the shield 20. The internal shields 18, 20 may be provided with a releasable adhesive coating on the shield surface opposite the cover part, such as Parker Hannifin 1085 adhesive. This permits the housing to be opened without damage to the shield or circuit board. The use of a conductive adhesive to secure the shield, assures reliable low resistance electrical conductivity between the shield, the housing, and the grounding trace.
FIG. 2 shows a plate-like shield device 40 that can be mounted at the upper surface 45 of the internal shield 18, opposite the lower surface 47 that engages the grounding trace on the circuit board. As shown in FIG. 3, the shielding device 40 includes a metal foil 41 such as a copper foil, which is coated on its opposite surfaces with conductive adhesive layers 42, 44. The conductive adhesive may be Parker Hannifin 1085, which comprises an acrylic pressure sensitive adhesive with conductive particles embedded therein. The molded flexible internal shield 18 is secured to the foil through the adhesive layer 44. The shielding device, including the foil 41, extends over the entire top of the shielded volume 23 and against the upper surface of the internal shield 18. The shielding device forms the top of a Faraday cage to enhance the shielding or screening of circuitry on the circuit board. Enhanced screening is achieved because a copper foil has a smoother surface than the brushed stainless steel surface of the cover parts, and because copper has a higher conductivity, resulting in a lower resistance connection between the internal shield 18 and the foil 41. The internal shield 18 is secured to the grounding trace 28 on the circuit board 14 by means of a conductive adhesive layer 46.
FIG. 4 shows a circuit board 14 and another internal shield 50 which forms three enclosures 52, 54, 56. One or more circuit components lies within each enclosure, and circuit components in the different enclosures are screened from one another and from circuitry outside the internal shield against electromagnetic interference. The shield 50 is secured to a conductive grounding trace 28' on the circuit board by a conductive adhesive such as one of the adhesives previously mentioned.
FIG. 5 illustrates a carrier strip 60 on which numerous internal shields 50 are releasably secured by releasable adhesive. In manufacture, this allows the shields to be transferred to a cover part or a circuit board after application of a conductive adhesive to the exposed surface, or after application to an adhesive already on the cover or circuit board. This permits direct transfer of the shields without damage or distortion and enables automatic application by machine. It will be appreciated that in a construction where a metal foil is employed to enhance the shielding, such foils could be similarly provided on a carrier strip such as 60 and automatically applied to a shield fitted to a board or cover.
The internal shield can be permanently secured by a conductive adhesive to the printed circuit board grounding trace or to a cover part, before assembly. Securement to the opposite trace or cover can be effected by a permanent setting conductive adhesive or by a releaseable conductive adhesive. Both sides could be secured by a releasable conductive adhesive to facilitate placement of a shield. The adhesive may be applied to the internal shield or to the trace or cover part. The adhesive may be applied from a tube just prior to assembly. The conductivity between internal shield and cover and/or trace is ensured without the requirement for compressive pressure. Various compressive fillers are available such as copper and graphite, and different molded elastomers are available for the shield such as polystyrene. The flexible conductive shield can be molded directly onto the circuit board or cover. Although the embodiments described employ a single internal shield on each face of the circuit board, a shield may be provided on one side only, or several shields may be provided on one or both sides of the circuit board.
FIG. 6 illustrates another arrangement, where a shielding device 60 is integrally molded with the internal shield 18'. Layers 62, 63 of adhesive bond the combination of internal shield 18' and the shielding device 60 to the board trace 28 and to the upper cover part 16.
Although terms such as "top" and "bottom" and arrows U, D (for up and down) are used to aid in the description of the parts as illustrated, the PC card can be made and used in any orientation with respect to the Earth.
Thus, the invention provides an internal PC card shield assembly that electromagnetically shields, or screens, circuit components in the card from one another without creating a local rigidized card area that could cause damage to the circuit board when the PC card flexes. The apparatus includes an internal shield of flexible and preferably elastomeric material which is electrically conductive. Elastomeric material has the advantage that it can compress and elongate to accommodate different thicknesses of the gap between the circuit board and cover part when the cover flexes. The thickness of the internal shield is at least half the thickness of the space between a face of a circuit board and an inner face of a sheet metal cover half, and preferably at least 90% of such thickness. Upper and lower surfaces of the shield are joined by electrically conductive adhesive to the circuit board and to a corresponding cover part. A shielding device can be used to cover the face of the shield opposite the circuit board, independently of the cover part. Such shielding device may include a continuous foil sheet held by a first adhesive layer to the shield and preferably held by another adhesive layer to the cover part.
Although particular embodiments of the invention have been described and illustrated herein, it is recognized that modifications and variations may readily occur to those skilled in the art, and consequently, it is intended that the claims be interpreted to cover such modifications and equivalents. | A PC card with a circuit board (14) and sheet metal cover parts (16, 17), is provided with a shielded volume (23, 29) where a circuit component (24) is isolated from circuit components outside the shielded volume. An internal shield (18) of electrically conductive material surrounds the shielded volume, and is engaged with a ground trace (28) on the circuit board. The internal shield is flexible so it bends when the sheet metal cover parts bend, to avoid breaking the circuit board. Layers of electrically conductive adhesive (42, 44, 46) couple the internal shield to the circuit board into one of the cover parts. A plate-like shielding device (40) can be provided, that includes a metal foil (41) that is bonded to the internal shield and that lies over the entire shielded volume. | 7 |
FIELD OF THE INVENTION
The present invention relates to a work space assembly for use during a collaboration among two or more sets of workers.
BACKGROUND OF THE INVENTION
Work space divider systems, which typically include partition systems that divide space into sub-spaces, are employed to assist collaborative activity, while also maintaining a level of privacy. In certain occupations, collaborative activity is essential for innovation. In many cases, especially large projects, such as programming projects that enlist dozens of individuals with varying assignments, which may include, design, coding, testing, quality control, marketing, sales and service, immediate face-to-face collaboration is difficult due to project members being physically separated. In most instances, teamwork requires one to walk distances or communicate over emails or text facilities, which are costly and inefficient. When groups of people need to interact, as between co-workers or supervisors, or other project team associates that involve disparate, but project related activities, there may be workspace arrangements vis-à-vis partitions, egress and ingress that can improve an individual's efficiencies, and creative contributions, and in some cases physical space arrangements act as a catalyst for the co-worker motivation and individual efficiencies.
Project managers are generally aware that there are times when they need privacy or personal space to perform certain employment and creative tasks. Other team members may desire privacy, or at times, degrees of privacy, to block out distractions. In other instances aside from the level of privacy a project manager or team may desire, he/she may also require a proximity to the individuals over whom they have supervisory responsibility and to their supervisory counterparts working on the other aspects of the same or similar projects. In this instance work spaces often must attempt to fulfill the multiple requirements of privacy, allowing workers to have their separate collaborative space, and yet offer proximity to one's immediate supervisor and others who may be more remotely related to a project.
What is needed is a workspace arrangement that optimizes a team member's focus on the assignments for which they are responsible, while allowing the member to interact with other team members and with members of other teams working on other aspects of the same or similar projects, while maximizing work flow and overall product development collaboration and efficiencies.
SUMMARY OF THE INVENTION
The invention relates to a workspace assembly for team collaboration wherein a circular area is divided into pie segments, wherein a first segment, containing a first enclosed workspace at a radial distance from an associated second workspace, is adjacent to a second segment containing a first enclosed workspace at a radial distance from an associated second workspace, each workspace collocated circumferentially, to a corresponding workspace.
In one embodiment of the invention, workspaces in a segment located radially outward from the center of the circle, are separated from other segments of collocated workspaces by angularly opposing separators.
In another embodiment the angularly opposing separators provide one or more functions of removability, levels of opacity or transparency between collocated workspaces, or electronic screens for communication.
In yet another embodiment of the invention a workspace assembly is collocated circumferentially to corresponding associated workspaces at associated concentric levels, wherein the levels rotate relative to other concentric levels, and additionally any workspace situated on a rotatable platform, rotates, so as to be reoriented with respect to an opposing workspace.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a plan view of an assembly of an arrangement of workspace in accordance with an embodiment of the present invention;
FIG. 2 shows a perspective view of an assembly of an arrangement of workspace in accordance with an embodiment of the present invention;
FIG. 3 shows a plan view of the moveable feature of a workspace in accordance with an embodiment of the present invention.
DESCRIPTION OF PREFERRED EMBODIMENT
The present invention is described with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may be embodied in different forms and should not be construed as limited to the embodiments set forth. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout.
FIG. 1 , FIG. 2 and FIG. 3 represents a workspace assembly for team collaboration comprising a first segment 103 a containing a first enclosed workspace 110 , at a radial distance from an associated second workspace 114 a , said first segment adjacent to a second segment 103 b containing a second enclosed workspace 110 at a radial distance from an associated third workspace, 114 b , said enclosed workspaces collocated circumferentially to corresponding workspaces, and said associated workspaces collocated circumferentially to corresponding associated workspaces.
More particularly, FIG. 1 shows an assembly 100 , which discloses a workspace for use during a collaboration among two or more sets of workers within an associated area 113 a , containing workers such as, X 1 , located in workspace 110 and workers X 2 , located in workspace 114 a . Each set of two or more workers, X 1 and X 2 , are radially separated, from a central core 102 . As shown in FIG. 1 and FIG. 3 , within associated area 113 a , one workspace 110 exists, however, any number of workspaces, such as 114 a may exist, as the application requires, such that each additional workspaces such as references as 114 a , 114 b , and 114 n , are located radially distant from workspace 110 . Each workspace level that includes workers, such as X 1 , Y 1 and X 2 , Y 2 , are collocated in outwardly radiating concentric circles around a center work area 102 .
In the embodiment shown in FIG. 1 , there are six segments, such as 103 a , or sets of workspaces, surrounding the center of the work area 102 . The two or more workers, X 1 , X 2 within segment 113 a , share a work association between themselves, and between the one or more workers of Y 1 , Y 2 within segment 113 b . There may be a multiplicity of associated areas, such as 113 a , 113 b . The segments 103 may be affiliated with different work tasks, such as salespersons in segment 113 a , and product design personnel in segment 113 b.
The individuals represented by the reference X 1 may share a work association among other sets of workers on the same level, such as Y 1 . Individuals, such as X 2 may share a work association among other sets of workers on the same level, such as Y 2 . In a non limiting application of the invention, X 1 may be the supervisor of X 2 . In one non limiting example,
Each of the two or more workers located at a first level, such as X 1 , Y 1 , utilize an enclosure 110 radially separate from the two or more workers X 2 , Y 2 located in workspace 114 a , 114 b , respectively. In one non limiting embodiment, the enclosure 110 is in the shape of an isosceles trapezium. The enclosure typically has glass outer walls 111 , and an entrance 116 . The enclosure 110 , includes at least one work surface 105 , at least one chair 104 , a controller 107 , that allows the operation of the various separator 118 a , 118 b , functions as well as communicate with the workers in workspace 114 a , 114 b , etc.
The enclosure 110 is also adjacent to its respective workspace, e.g., workspace 114 a , where each workspace 114 a , also has at least one work surface 108 , at least one chair 106 , and a multifunctional partition 109 ( FIG. 2 ).
Again referring to FIG. 1 , each segment 113 a may be separated from an adjacent segment 113 b by angularly opposing separators, as by way of example, 118 a , 118 b , and 118 c . In one embodiment some or all the separators are removed. The opposing separators 118 a , 118 b , and 118 c may be constructed in whole or in part of a material such as glass or other optically transparent material or a material that reduces noise. Additionally the separators may optionally function in whole or part, as display screens, smart boards or white boards, allowing information to be communicated or collaboratively shared, between and among segments (e.g., 103 a , 103 b ).
Turning to FIG. 2 , the workspace assembly for team collaboration includes one or more separate circumferentially collocated workspaces utilizing angularly opposing walls, each workspace containing an enclosure 110 radially separating the workspace 114 a having at least one work surface 108 , and at least one chair 106 , and a multifunctional separator 109 between the enclosure and the workspace.
One or more of the individuals located in workspace 110 , may using the controller 107 , electronically control a customizable work-related message or theme transmitted, projected or displayed on the separator 118 a and/or separator 118 b or the multifunctional partition 109 . Such information may be in the form of work-related messages, projections or displays, for a variety of purposes, including one of project code names, motivational, inspirational messaging, stress reducing, team-building, alerts, work instructions, and other applications that a management deems necessary in a working environment. In other instances, a non-limiting embodiment of the invention the separators 118 a , 118 b , are made transparent to increase team collaboration, or opaque or partially opaque to reduce distraction, shield work product from third parties, or for general confidential or privacy purposes.
In one non-limiting embodiment of the invention one or more separators 118 a , 118 b may be controlled such that a color code scheme may be employed to features or elements of the separator 118 a , 118 b i.e., surface and/or edging, to designate group designation, or affinity or project work mode.
Referring to FIG. 1 and FIG. 2 , by way of example, and not limitation, the color green may be displayed on all or part of a separator 118 a , 118 b , and 118 c , between associated areas 113 a , 113 b that for example might be developing environmentally friendly packaging, or multiple colors may be displayed as described to show collaboration between working groups for example, between 113 a and another working segment 113 b responsible for example for market testing.
In one non-limiting embodiment of the invention one or more separators 118 a , 118 b are constructed in whole or part from smart glass or switchable glass in which features of the glass are altered by for example the application of voltage, light or heat to alter the glass from translucent to transparent, or changing from blocking some (or all) wavelengths of light to letting light pass through which may be accomplished through a variety of technologies such as electrochromic, photochromic, thermos-chromic, suspended particle, micro-blind and polymer dispersed liquid crystal technologies.
In FIG. 2 , the multifunctional partition 109 , may represent a display, smart board or white board, allowing information to be communicated or collaboratively shared, between individuals such as located in workspace 114 a , and among the individuals in work space 110 , or in other collocated segments, 113 b.
Referring to FIG. 3 , one non-limiting embodiment of the invention allows any one or more concentric levels 130 , for example, to rotate 136 , and thereby move relative to other concentric levels, thus shifting the associated arrangement of workspaces 114 a , 114 b , 114 n and 110 . Similarly, any workspaces 114 a , 114 b , 114 n and 110 may be placed on a rotatable platform, to rotate 134 , so as to be oriented 132 to face an opposing workspaces, such as 114 a facing 114 b or 110 facing 114 a , 114 b , 114 n . Mechanisms for rotation are well known in the mechanical arts.
While the foregoing invention has been described with reference to the above embodiments, additional modifications and changes can be made without departing from the spirit of the invention. | This invention generally relates to a workspace based on a central-themed geometric configuration, wherein a circular area is divided into pie segments that relate a first team of working associations, separated radially, from a second team of working associations, first and second teams of associations collocated circumferentially into teams of differing and similar tasked members. | 4 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority to Japanese Patent Application No. 2010-137078, filed in the Japan Patent Office on Jun. 16, 2010, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention relates to a negative electrode for lithium secondary batteries and a lithium secondary battery including the negative electrode. The present invention relates to a negative electrode for lithium secondary batteries that uses negative electrode active material particles containing at least one of silicon and a silicon alloy, and to a lithium secondary battery including the negative electrode.
[0004] 2. Description of Related Art
[0005] In recent years, there has been a demand for increasing the energy density of lithium secondary batteries. With this trend, a negative electrode active material that can further increase energy density over that of graphite materials, which have been commonly used as a negative electrode active material, has been actively studied. An example of such a negative electrode active material is an alloy material that contains an element such as Al, Sn, or Si and forms an alloy with lithium.
[0006] The alloy material that contains an element such as Al, Sn, or Si and forms an alloy with lithium is a negative electrode active material that occludes lithium through an alloying reaction with lithium, and has a volume specific capacity higher than that of graphite materials. Therefore, by using, as a negative electrode active material, the alloy material that contains an element such as Al, Sn, or Si and forms an alloy with lithium, a lithium secondary battery having high energy density can be obtained.
[0007] However, in a negative electrode that uses, as a negative electrode active material, the alloy material that contains an element such as Al, Sn, or Si and forms an alloy with lithium, the volume of the negative electrode active material is significantly changed when charge and discharge are performed. That is, when lithium is occluded and released. Thus, a negative electrode active material becomes readily powdered or a negative electrode mixture layer becomes readily detached from a current collector. When such phenomena occur, the current-collecting performance in the negative electrode decreases and the charge-discharge cycle characteristics of lithium secondary batteries become poor.
[0008] To solve such problems, for example, Japanese Published Unexamined Patent Application No. 2002-260637 (Patent Document 1) discloses a method in which a mixture layer that contains a polyimide binder and active material particles containing at least one of silicon and a silicon alloy is formed on a current collector and then the mixture layer is sintered in a non-oxidizing atmosphere. A negative electrode obtained by this method provides good cycle characteristics.
[0009] WO 04/004031 A1 (Patent Document 2), Japanese Published Unexamined Patent Application No. 2007-242405 (Patent Document 3), and Japanese Published Unexamined Patent Application No. 2008-34352 (Patent Document 4) disclose that good cycle characteristics can be achieved by optimizing a negative electrode binder contained in a negative electrode mixture layer. Patent Document 2 discloses that a polyimide having desired mechanical properties is used as a negative electrode binder. Patent Document 3 discloses that an imide compound obtained by decomposing a binder precursor composed of polyimide or polyamic acid through heat treatment is used as a negative electrode binder. Patent Document 4 discloses that a polyimide composed of 3,3′,4,4′-benzophenonetetracarboxylic dianhydride and m-phenylenediamine or 4,4′-diaminodiphenylmethane is used as a negative electrode binder.
BRIEF SUMMARY OF THE INVENTION
[0010] There has still been a demand for further improving the charge-discharge cycle characteristics of lithium secondary batteries.
[0011] An object of the present invention is to provide a negative electrode for lithium secondary batteries that achieves a lithium secondary battery which uses at least one of silicon and a silicon alloy as a negative electrode active material and thus has good charge-discharge cycle characteristics.
[0012] A negative electrode for lithium secondary batteries according to the present invention includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is formed on the negative electrode current collector. The negative electrode active material layer contains a binder and negative electrode active material particles containing at least one of silicon and a silicon alloy. The binder is a polyimide resin formed by imidization of a tetracarboxylic acid or tetracarboxylic anhydride and a diamine. The diamine contains a diamine having at least one hydroxyl group. The hydroxyl group of the diamine has high polarity. The introduction of a hydroxyl group in the polyimide resin constituting the binder can improve the adhesion between the polyimide resin and the negative electrode active material particles whose surfaces have high polarity. Thus, a lithium secondary battery having good charge-discharge cycle characteristics can be obtained by using the negative electrode for lithium secondary batteries according to the present invention.
[0013] A carboxyl group, which has high polarity like the hydroxyl group, may also be used as a functional group and is also believed to improve the adhesion with the negative electrode active material particles. This means that a diamine having a carboxyl group can be used instead of the diamine having a hydroxyl group. However, if a diamine having a carboxyl group is used, the carboxyl group may react with an amino group of the other diamines, forming an amide bond. As a result, a polyamide-imide resin is produced and a polyimide resin is may not be suitably produced. Therefore, a diamine having a hydroxyl group is preferably used in the present invention.
[0014] In the present invention, the diamine having a hydroxyl group may be a diamine having a single hydroxyl group or a diamine having two or more hydroxyl groups. Among these diamines, a diamine having a single hydroxyl group is preferably used. This is because the polymerization reaction between tetracarboxylic acid and diamine is more easily facilitated with a diamine having a single hydroxyl group than the case where a diamine having two or more hydroxyl groups is used.
[0015] An example of the diamine having a single hydroxyl group is diaminomonohydroxybenzene (also referred to as diaminophenol). Examples of the diaminomonohydroxybenzene include 2,3-diaminophenol, 2,5-diaminophenol, 2,6-diaminophenol, 3,4-diaminophenol, and 3,5-diaminophenol represented by formula (1). Among them, 3,5-diaminophenol represented by the formula (1) is preferably used as the diamine having a single hydroxyl group. In 3,5-diaminophenol, two amino groups are present in meta-positions. With 3,5-diaminophenol, high flexibility and strength that are characteristics of polyimide resins can be achieved. The hydroxyl group is oriented so as to be perpendicular to a molecular chain constituting the basic skeleton of the polyimide resin. Thus, a hydroxyl group is easily bonded to the negative electrode active material and the negative electrode current collector. This can provide better adhesion.
[0000]
[0016] Examples of a diamine having two hydroxyl groups include diaminodihydroxybenzene, diaminodihydroxybenzophenone, diaminodihydroxybiphenyl, diaminodihydroxydiphenylmethane, diaminodihydroxydiphenyl ether, and diaminodihydroxydiphenyl sulfone. Examples of the diaminodihydroxybenzene include 1,3-diamino-4,5-dihydroxybenzene and 1,3-diamino-4,6-dihydroxybenzene. Examples of the diaminodihydroxybenzophenone include 3,3′-diamino-4,4′-dihydroxybenzophenone, 4,4′-diamino-3,3′-dihydroxybenzophenone, and 4,4′-diamino-2,2′-dihydroxybenzophenone. Examples of the diaminodihydroxybiphenyl include 3,3′-diamino-4,4′-dihydroxybiphenyl, 4,4′-diamino-3,3′-dihydroxybiphenyl, and 4,4′-diamino-2,2′-dihydroxybiphenyl. Examples of the diaminodihydroxydiphenylmethane include 3,3′-diamino-4,4′-dihydroxydiphenylmethane, 4,4′-diamino-3,3′-dihydroxydiphenylmethane, and 4,4′-diamino-2,2′-dihydroxydiphenylmethane. Examples of the diaminodihydroxydiphenyl ether include 3,3′-diamino-4,4′-dihydroxydiphenyl ether, 4,4′-diamino-3,3′-dihydroxydiphenyl ether, and 4,4′-diamino-2,2′-dihydroxydiphenyl ether. Examples of the diaminodihydroxydiphenyl sulfone include 3,3′-diamino-4,4′-dihydroxydiphenyl sulfone, 4,4′-diamino-3,3′-dihydroxydiphenyl sulfone, and 4,4′-diamino-2,2′-dihydroxydiphenyl sulfone.
[0017] An example of a diamine having three hydroxyl groups is diaminotrihydroxybenzene such as 1,3-diamino-4,5,6-trihydroxybenzene.
[0018] Examples of a diamine having four hydroxyl groups include diaminotetrahydroxybenzene, diaminotetrahydroxybenzophenone, diaminotetrahydroxybiphenyl, diaminotetrahydroxydiphenylmethane, diaminotetrahydroxydiphenyl ether, and diaminotetrahydroxydiphenyl sulfone. An example of the diaminotetrahydroxybenzene is 1,3-diamino-2,4,5,6-tetrahydroxybenzene. An example of the diaminotetrahydroxybenzophenone is 4,4′-diamino-2,2′,5,5′-tetrahydroxybenzophenone. A specific example of the diaminotetrahydroxybiphenyl is 4,4′-diamino-2,2′,5,5′-tetrahydroxybiphenyl. An example of the diaminotetrahydroxydiphenylmethane is 4,4′-diamino-2,2′,5,5′-tetrahydroxydiphenylmethane. An example of the diaminotetrahydroxydiphenyl ether is 4,4′-diamino-2,2′,5,5′-tetrahydroxydiphenyl ether. An example of the diaminotetrahydroxydiphenyl sulfone is 4,4′-diamino-2,2′,5,5′-tetrahydroxydiphenyl sulfone.
[0019] In the present invention, the tetracarboxylic acid used together with a diamine to form a polyimide resin may be a tetracarboxylic anhydride.
[0020] Examples of the tetracarboxylic anhydride include aromatic tetracarboxylic dianhydrides such as 1,2,4,5-benzenetetracarboxylic-1,2:4,5-dianhydride (also called pyromellitic dianhydride), 3,3′,4,4′-benzophenonetetracarboxylic dianhydride represented by formula (2), 3,3′,4,4′-biphenyltetracarboxylic dianhydride represented by formula (3), 3,3′,4,4′-diphenylsulfonetetracarboxylic dianhydride, 3,3′,4,4′-diphenylethertetracarboxylic dianhydride, and 3,3′,4,4′-diphenylmethanetetracarboxylic dianhydride. Among them, 3,3′,4,4′-benzophenonetetracarboxylic dianhydride and 3,3′,4,4′-biphenyltetracarboxylic dianhydride are preferably used as the tetracarboxylic anhydride. Since 3,3′,4,4′-benzophenonetetracarboxylic dianhydride and 3,3′,4,4′-biphenyltetracarboxylic dianhydride have a molecular structure in which two aromatic rings are positioned in the same plane, a polyimide resin having balanced mechanical strength and flexibility can be obtained.
[0000]
[0021] In the case where the diamine represented by the formula (1) and the tetracarboxylic anhydride represented by the formula (2) are employed, a polyimide resin having a structure represented by formula (4) is obtained. In the case where the diamine represented by the formula (1) and the tetracarboxylic anhydride represented by the formula (3) are employed, a polyimide resin having a structure represented by formula (5) is obtained.
[0000]
[0022] In the present invention, the diamine may be a diamine having a hydroxyl group. The binder may also be a polyimide resin formed by imidization of a tetracarboxylic acid or tetracarboxylic anhydride and a diamine having a hydroxyl group and a diamine having no hydroxyl group. By employing a diamine having no highly reactive hydroxyl group in addition to the diamine having a hydroxyl group, a polyimide resin having a high degree of polymerization and a high molecular weight is easily formed.
[0023] An example of the diamine having no hydroxyl group is an aromatic diamine. Examples of the aromatic diamine include m-phenylenediamine represented by formula (6), p-phenylenediamine, 3,3′-diaminobenzophenone, 4,4′-diaminobiphenyl, 4,4′-diaminodiphenylsulfone, 4,4′-diaminophenyl ether, 4,4′-diaminophenylmethane, 2,2-bis(4-(4-aminophenoxy)phenyl)propane, 1,4-bis(3-aminophenoxy)benzene, and 1,4-bis(4-aminophenoxy)benzene. Among them, m-phenylenediamine represented by the formula (6) is preferably used. In m-phenylenediamine, an amino group is bonded to a meta-position of a single aromatic ring. With m-phenylenediamine, a polyimide resin having balanced mechanical strength and flexibility can be obtained.
[0024] In the case where m-phenylenediamine represented by the formula (6) and the tetracarboxylic anhydride represented by the formula (2) are employed, a polyimide resin having a structure represented by formula (7) is obtained. In the case where m-phenylenediamine represented by the formula (6) and the tetracarboxylic anhydride represented by the formula (3) are employed, a polyimide resin having a structure represented by formula (8) is obtained.
[0000]
[0025] When both the diamine having a hydroxyl group and the diamine having no hydroxyl group are employed, the ratio between the diamine having a hydroxyl group and the diamine having no hydroxyl group is preferably 10:90 to 50:50 and more preferably 10:90 to 30:70. If the content of the diamine having no hydroxyl group is excessively low and the content of the diamine having a hydroxyl group is excessively high, a high degree of polymerization sometimes cannot be achieved. If the content of the diamine having no hydroxyl group is excessively high and the content of the diamine having a hydroxyl group is excessively low, the adhesion in the negative electrode is decreased and thus the cycle lifetime of lithium secondary batteries is sometimes shortened.
[0026] In the present invention, the negative electrode current collector is not particularly limited as long as it has conductivity. The negative electrode current collector can be composed of, for example, a conductive metal foil. Examples of the conductive metal foil include foils composed of a metal such as copper, nickel, iron, titanium, cobalt, manganese, tin, silicon, chromium, or zirconium or an alloy containing at least one of the foregoing metals. Among them, a copper thin film or a foil composed of an alloy containing copper is preferred because the conductive metal foil preferably contains a metal element that easily diffuses into active material particles.
[0027] The thickness of the negative electrode current collector is not particularly limited, and may be, for example, about 10 m to 100 m.
[0028] In the present invention, the negative electrode active material particles are not particularly limited as long as they contain at least one of silicon and a silicon alloy. The silicon alloy is not particularly limited as long as it is an alloy that functions as a negative electrode active material. Examples of the silicon alloy include a solid solution, an intermetallic compound, and an eutectic alloy of silicon and at least one element other than silicon. The silicon alloy can be produced by arc melting, liquid quenching, mechanical alloying, sputtering, chemical vapor deposition, firing, or the like. Examples of the liquid quenching include single-roller quenching, double-roller quenching, and various atomization processes such as a gas atomization process, a water atomization process, and a disk atomization process.
[0029] The negative electrode active material particles may be particles that are composed of at least one of silicon and a silicon alloy and whose surfaces are coated with a metal or an alloy. Examples of the coating method include electroless plating, electroplating, chemical reduction, vapor deposition, sputtering, and chemical vapor deposition. The metal that coats the surfaces of particles is preferably the same metal as that used for the conductive metal foil constituting the negative electrode current collector or the conductive metal powder below. By coating the particles with the same metal as that used for the conductive metal foil or the conductive metal powder, the linkage between the current collector and the conductive metal powder during sintering is considerably improved, resulting in better charge-discharge cycle characteristics.
[0030] The average particle size of the negative electrode active material particles is not particularly limited, and is, for example, preferably 100 m or less and more preferably 50 m or less.
[0031] In the present invention, the negative electrode mixture layer may further contain conductive powder such as conductive metal powder or conductive carbon powder. Preferably, the conductive metal powder may be composed of the same material as that of the conductive metal foil used as the negative electrode current collector. Powder composed of a metal such as copper, nickel, iron, titanium, or cobalt or an alloy of the foregoing is preferably used as the conductive metal powder. The average particle size of the conductive powder is not particularly limited, and is preferably 100 m or less and more preferably 50 m or less.
[0032] Monomer components other than the diamine and the at least one of a tetracarboxylic acid and a tetracarboxylic dianhydride may be used to form the polyimide resin. Examples of the monomer components other than the diamine include hexavalent or higher polycarboxylic acids, hexavalent or higher polycarboxylic acid anhydrides, and trivalent or higher polyamines.
[0033] The polycarboxylic acid and polycarboxylic acid anhydride react with a diamine or a polyamine during the heat treatment performed after the application and drying of negative electrode mixture slurry. The polyamine also reacts with a tetracarboxylic anhydride or the like during the heat treatment performed after the application and drying of negative electrode mixture slurry. Since a crosslinked structure can be introduced in the polyimide resin through these reactions, a polyimide resin having higher mechanical strength can be obtained. As a result, the charge-discharge cycle characteristics can be further improved.
[0034] Examples of the polycarboxylic acid include benzenehexacarboxylic acid (mellitic acid) and 1,2,3,4,5,6-cyclohexanehexacarboxylic acid. Examples of the polycarboxylic acid anhydride include benzenehexacarboxylic acid (mellitic acid) anhydride and 1,2,3,4,5,6-cyclohexanehexacarboxylic acid anhydride.
[0035] Examples of the polyamine include aromatic triamines such as tris(4-aminophenyl)methanol (also called pararosaniline), tris(4-aminophenyl)methane, 3,4,4′-triaminodiphenyl ether, 3,4,4′-triaminobenzophenone, 3,4,4′-triaminodiphenylmethane, 1,4,5-triaminonaphthalene, tris(4-aminophenyl)amine, 1,2,4-triaminobenzene, and 1,3,5-triaminobenzene; triamines such as 2,4,6-triamino-1,3,5-triazine (also called melamine) and 1,3,5-triaminocyclohexane; and tetraamines such as tetrakis(4-aminophenyl)methane, 3,3′,4,4′-tetraminodiphenyl ether, 3,3′,4,4′-tetraminobenzophenone, 3,3′,4,4′-tetraminodiphenylmethane, and N,N,N′,N′-tetrakis(4-methylphenyl)benzidine.
[0036] The production method of the negative electrode for lithium secondary batteries according to the present invention is not particularly limited. The negative electrode for lithium secondary batteries according to the present invention can be produced, for example, through the following process.
[0037] First, a binder precursor solution is prepared. Specifically, a tetracarboxylic dianhydride is caused to react with an alcohol compound having a single hydroxyl group, such as a monohydric alcohol (e.g., methanol, ethanol, isopropanol, and butanol), in a solvent to form an ester compound of the tetracarboxylic dianhydride with an alcohol. A diamine having a hydroxyl group is added to the resultant solution to prepare a binder precursor solution containing monomer components of a polyimide resin.
[0038] Negative electrode active material particles are then dispersed in the binder precursor solution to prepare a negative electrode mixture slurry. The negative electrode mixture slurry is applied on the surface of a negative electrode current collector. The negative electrode current collector on which the negative electrode mixture slurry has been applied is heat-treated in a non-oxidizing atmosphere to cause polymerization reaction and imidization reaction between the monomer components of a polyimide resin, whereby a polyimide resin is formed. As a result, a negative electrode for lithium secondary batteries including a negative electrode active material layer formed on the negative electrode current collector can be completed.
[0039] In the above-described production method, the binder precursor solution used to form the negative electrode active material layer and containing monomer components of a polyimide resin has a lower viscosity than a binder precursor in a polymer state, such as polyamic acid, which is commonly used as a precursor of a polyimide resin. Therefore, when the negative electrode mixture slurry is prepared, the binder precursor solution containing monomer components of a polyimide resin easily enters the uneven surfaces of the negative electrode active material particles. Furthermore, when the negative electrode mixture slurry is applied on the negative electrode current collector, the binder precursor solution easily enters the uneven surface of the negative electrode current collector. This produces a significant anchor effect between the negative electrode active material particles and between the negative electrode active material particles and the negative electrode current collector. Thus, the adhesion between the negative electrode mixture layer and the negative electrode current collector can be further improved.
[0040] In the production method of the negative electrode, the heat treatment temperature of the negative electrode mixture slurry that has been applied and dried is preferably lower than the 5% mass decrease temperature of a negative electrode binder. In the case where the negative electrode binder has glass transition temperature, the heat treatment temperature of the negative electrode mixture slurry is preferably higher than the glass transition temperature of the negative electrode binder. In this case, since the negative electrode binder has plasticity, the binder more easily enters the uneven surfaces of the negative electrode active material particles or negative electrode current collector. Consequence, an anchor effect is produced more significantly, which can provide better adhesion.
[0041] A lithium secondary battery according to the present invention includes an electrode body including the negative electrode for lithium secondary batteries according to the present invention, a positive electrode, and a separator disposed between the negative electrode and the positive electrode, and a non-aqueous electrolyte impregnated into the electrode body. As described above, the negative electrode for lithium secondary batteries according to the present invention has good adhesion. Thus, a lithium secondary battery including the negative electrode for lithium secondary batteries according to the present invention has good charge-discharge cycle characteristics.
[0042] In the present invention, the positive electrode, the separator, and the non-aqueous electrolyte are not particularly limited. For example, a known positive electrode, separator, and non-aqueous electrolyte can be used.
[0043] The positive electrode normally includes a positive electrode current collector composed of a conductive metal foil or the like and a positive electrode mixture layer formed on the positive electrode current collector. The positive electrode mixture layer contains a positive electrode active material. The positive electrode active material is not particularly limited as long as lithium is electrochemically inserted and removed. Examples of the positive electrode active material include lithium transition metal oxides such as LiCoO 2 , LiNiO 2 , LiMn 2 O 4 , LiMnO 2 , LiCO 0.5 Ni 0.5 O 2 , and LiNi 0.7 CO 0.2 Mn 0.1 O 2 and metal oxides not containing lithium such as MnO 2 .
[0044] A solvent used for the non-aqueous electrolyte is also not particularly limited. Examples of the solvent used for the non-aqueous electrolyte include cyclic carbonates such as ethylene carbonate, propylene carbonate, butylene carbonate, and fluoroethylene carbonate; chain carbonates such as dimethyl carbonate, methylethyl carbonate, and diethyl carbonate; and mixed solvents of the cyclic carbonates and the chain carbonates.
[0045] A solute used for the non-aqueous electrolyte is also not particularly limited. Examples of the solute used for the non-aqueous electrolyte include LiPF 6 , LiBF 4 , LiCF 3 SO 3 , LiN(CF 3 SO 2 ) 2 , LiN(C 2 F 5 SO 2 ) 2 , LiN(CF 3 SO 2 )(C 4 F 9 SO 2 ), LiC(CF 3 SO 2 ) 3 , LiC(C 2 F 5 SO 2 ) 3 , and the mixtures of the foregoing. A gel polymer electrolyte obtained by impregnating a polymer electrolyte such as polyethylene oxide or polyacrylonitrile with an electrolytic solution and an inorganic solid electrolyte such as LiI or Li 3 N may be used as the electrolyte.
[0046] The non-aqueous electrolyte preferably contains CO 2 .
[0047] According to the present invention, there can be provided a lithium secondary battery that uses at least one of silicon and a silicon alloy as a negative electrode active material and thus has good charge-discharge cycle characteristics.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0048] FIG. 1 is a schematic perspective view of an electrode body.
[0049] FIG. 2 is a schematic plan view of a battery produced in Example 1.
[0050] FIG. 3 is a schematic sectional view taken along line III-III of FIG. 2 .
DETAILED DESCRIPTION OF THE INVENTION
[0051] The present invention will now be described in detail based on Examples. The present invention is not limited by Examples below, and any modification may be made without departing from the scope of the present invention.
Example 1
Preparation of Negative Electrode
<Preparation of Negative Electrode Active Material>
[0052] First, polycrystalline silicon fine particles were introduced and monosilane (SiH 4 ) was inserted into a fluidized bed having an inside temperature of 800° C. to prepare particulate polycrystalline silicon. The particulate polycrystalline silicon was pulverized with a jet mill and classified with a classifier to prepare polycrystalline silicon powder (negative electrode active material). The median particle size of the polycrystalline silicon powder was 10 m. The crystallite size of the polycrystalline silicon powder was 44 nm.
[0053] Herein, the median particle size is a particle size when the cumulative distribution percentage by volume reaches 50%, the particle size distribution being measured by laser diffraction. The crystallite size of the polycrystalline silicon powder was calculated from the Scherrer equation using the half width of a (111) peak of silicon measured by powder X-ray diffractometry.
<Preparation of Negative Electrode Binder Precursor>
[0054] A substance esterified through the reaction between 3,3′,4,4′-benzophenonetetracarboxylic dianhydride represented by formula (2) and two equivalents of ethanol, 3,5-diaminophenol (1,3-diamino-5-hydroxybenzene) represented by formula (1), and m-phenylenediamine represented by formula (6) were dissolved in N-methyl-2-pyrrolidone (NMP) to obtain a binder precursor solution a1. The molar ratio of (3,3′,4,4′-benzophenonetetracarboxylic dianhydride represented by formula (2)): (3,5-diaminophenol represented by formula (1)): (m-phenylenediamine represented by formula (6)) was adjusted to be 100:10:90.
[0000]
<Preparation of Negative Electrode Mixture Slurry>
[0055] The negative electrode active material prepared above, graphite powder having an average particle size of 3 m and serving as a negative electrode conductive agent, and the negative electrode binder precursor solution a1 were mixed with each other to prepare a negative electrode mixture slurry. The mass ratio of (negative electrode active material powder):(negative electrode conductive agent powder):(negative electrode binder (obtained after the negative electrode binder precursor solution a1 was subjected to NMP removal by drying, polymerization reaction, and imidization reaction)) was adjusted to be 89.5:3.7:6.8.
<Preparation of Negative Electrode>
[0056] Both faces of a copper alloy foil having a thickness of 18 m (C7025 alloy foil having a composition of 96.2 wt % of Cu, 3 wt % of Ni, 0.65 wt % of Si, and 0.15 wt % of Mg) were roughened by electrolysis so as to have a surface roughness Ra (JIS B 0601-1994) of 0.25 m and an average distance between local peaks S (JIS B 0601-1994) of 0.85 m. This was used as a negative electrode current collector.
[0057] The negative electrode mixture slurry prepared above was applied on both faces of the negative electrode current collector in air at 25° C., dried in air at 120° C., and rolled in air at 25° C. After the rolling, the resultant body was cut into rectangles each having a length of 380 mm and a width of 52 mm and then heat-treated in an argon atmosphere at 400° C. for 10 hours. Thus, a negative electrode including negative electrode mixture layers formed on both faces of the negative electrode current collector was prepared.
[0058] The amount of the negative electrode mixture layers formed on the negative electrode current collector was 5.6 mg/cm 2 and the thickness of each of the negative electrode mixture layers was 56 m.
[0059] Lastly, a nickel plate serving as a negative electrode current collector tab was connected to the end portion of the negative electrode.
[0060] The following experiment was performed in order to confirm whether a polyimide compound was produced from the binder precursor solution 1a through heat treatment. The binder precursor solution a1 was dried in air at 120° C. to remove NMP, and then heat-treated in an argon atmosphere at 400° C. for 10 hours as in the heat treatment described above. The infrared (IR) absorption spectrum of the resultant body was measured. A peak derived from an imide bond was detected at about 1720 cm −1 . Accordingly, it was confirmed that polymerization reaction and imidization reaction were caused through the heat treatment of the binder precursor solution a1 and thus a polyimide compound was produced.
[Preparation of Positive Electrode]
<Preparation of Lithium Transition Metal Compound Oxide>
[0061] Li 2 CO 3 and CoCO 3 serving as positive electrode active materials were mixed with each other in a mortar so that the molar ratio between Li and Co was 1:1, heat-treated in air at 800° C. for 24 hours, and then pulverized. Consequently, a lithium-cobalt compound oxide powder represented by LiCoO 2 and having an average particle size of 11 m was obtained. In Example 1, this lithium-cobalt compound oxide powder was used as a positive electrode active material powder.
[0062] The BET specific surface of the resultant positive electrode active material powder was 0.37 m 2 /g.
<Preparation of Positive Electrode>
[0063] The positive electrode active material powder prepared above, a carbon material powder serving as a positive electrode conductive agent, and polyvinylidene fluoride serving as a positive electrode binder were added to N-methyl-2-pyrrolidone serving as a dispersion medium, and the mixture was kneaded to prepare a positive electrode mixture slurry. The mass ratio of (positive electrode active material powder):(positive electrode conductive agent):(positive electrode binder) was adjusted to be 95:2.5:2.5.
[0064] The positive electrode mixture slurry was applied on both faces of an aluminum foil serving as a positive electrode current collector and having a thickness of 15 m, a length of 402 mm, and a width of 50 mm, dried, and then rolled. The coated portion on the front face had a length of 340 mm and a width of 50 mm. The coated portion on the back face had a length of 270 mm and a width of 50 mm. The amount of the positive electrode mixture layers formed on both faces of the current collector was 48 mg/cm 2 . The thickness of the positive electrode in a portion where the positive electrode mixture layers were formed on both faces of the current collector was 143 m.
[0065] Lastly, an aluminum plate serving as a positive electrode current collector tab was connected to the positive electrode current collector in a portion where the positive electrode mixture layer was not formed.
[Preparation of Non-Aqueous Electrolyte]
[0066] After 1 mol/L lithium hexafluorophosphate (LiPF 6 ) was dissolved, in an argon atmosphere, in a solvent obtained by mixing fluoroethylene carbonate (FEC) and methylethyl carbonate (MEC) in a volume ratio of 2:8, 0.4 wt % of carbon dioxide gas was dissolved therein to prepare a non-aqueous electrolyte.
[Preparation of Electrode Body]
[0067] The above-described positive electrode, the above-described negative electrode, and two separators made of a polyethylene microporous membrane were prepared. Each of the separators made of a polyethylene microporous membrane had a thickness of 20 m, a length of 450 mm, a width of 54.5 mm, a piercing strength of 340 g, and a porosity of 39%. The positive electrode, the negative electrode, and the separators were wound around a columnar core in a spiral form so that the positive electrode and the negative electrode faced each other with the separators therebetween and the positive electrode current collector tab and the negative electrode current collector tab came to be located at the outermost periphery. After that, the core was removed to prepare a spiral electrode body. The electrode body was then pressed to obtain an electrode body shown in FIG. 1 .
[0068] As shown in FIG. 1 , the obtained electrode body 5 is flat and includes a positive electrode current collector tab 3 and a negative electrode current collector tab 4 .
[Production of Battery]
[0069] The flat electrode body and electrolyte prepared above were inserted in a casing made of an aluminum laminate in a carbon dioxide atmosphere of 25° C. and 1 atmospheric pressure to produce a flat battery A 1 according to Example 1.
[0070] FIG. 2 is a schematic plan view of the battery A 1 . FIG. 3 is a schematic sectional view of the battery A 1 .
[0071] As shown in FIGS. 2 and 3 , the battery A 1 includes a flat electrode body 5 having a positive electrode 6 , a negative electrode 7 , separators 8 , a positive electrode current collector tab 3 , and a negative electrode current collector tab 4 . The flat electrode body 5 is accommodated in a casing 1 made of an aluminum laminate and having a sealed portion 2 subjected to heat seal treatment.
Example 2
[0072] A flat battery A 2 according to Example 2 was produced by the same method as in Example 1, except that the binder precursor solution was prepared so that the molar ratio of (3,3′,4,4′-benzophenonetetracarboxylic dianhydride represented by formula (2)): (3,5-diaminophenol represented by formula (1)): (m-phenylenediamine represented by formula (6)) was adjusted to be 100:30:70.
Example 3
[0073] A flat battery A 3 according to Example 3 was produced by the same method as in Example 1, except that the binder precursor solution was prepared so that the molar ratio of (3,3′,4,4′-benzophenonetetracarboxylic dianhydride represented by formula (2)): (3,5-diaminophenol represented by formula (1)): (m-phenylenediamine represented by formula (6)) was adjusted to be 100:50:50.
Example 4
[0074] A flat battery A 4 according to Example 4 was produced by the same method as in Example 1, except that 3,3′,4,4′-biphenyltetracarboxylic dianhydride represented by formula (3) was used instead of 3,3′,4,4′-benzophenonetetracarboxylic dianhydride represented by formula (2).
[0000]
Example 5
[0075] A flat battery A 5 according to Example 5 was produced by the same method as in Example 2, except that 3,3′,4,4′-biphenyltetracarboxylic dianhydride represented by formula (3) was used instead of 3,3′,4,4′-benzophenonetetracarboxylic dianhydride represented by formula (2).
Example 6
[0076] A flat battery A 6 according to Example 6 was produced by the same method as in Example 3, except that 3,3′,4,4′-biphenyltetracarboxylic dianhydride represented by formula (3) was used instead of 3,3′,4,4′-benzophenonetetracarboxylic dianhydride represented by formula (2).
Comparative Example 1
[0077] A flat battery B 1 according to Comparative Example 1 was produced by the same method as in Example 1, except that the binder precursor solution was prepared without using 3,5-diaminophenol represented by formula (1) so that the molar ratio of (3,3′,4,4′-benzophenonetetracarboxylic dianhydride represented by formula (2)): (m-phenylenediamine represented by formula (6)) was adjusted to be 100:100.
Comparative Example 2
[0078] A flat battery B 2 according to Comparative Example 2 was produced by the same method as in Example 2, except that the binder precursor solution was prepared without using 3,5-diaminophenol represented by formula (1) so that the molar ratio of (3,3′,4,4′-biphenyltetracarboxylic dianhydride represented by formula (3)): (m-phenylenediamine represented by formula (6)) was adjusted to be 100:100.
[Evaluation of Charge-Discharge Cycle Characteristics]
[0079] Regarding the batteries A 1 to A 6 , B 1 , and B 2 , the charge-discharge cycle characteristics were evaluated under the following charge-discharge cycle conditions. Table 1 shows the results.
Charge-Discharge Cycle Conditions
[0080] Charge Conditions at the First Cycle
[0081] After a constant-current charge was performed at a current of 50 mA for 4 hours, a constant-current charge was performed at a current of 200 mA until the battery voltage reached 4.2 V and then a constant-voltage charge was performed at a voltage of 4.2 V until the current value reached 50 mA.
[0082] Discharge Conditions at the First Cycle
[0083] A constant-current discharge was performed at a current of 200 mA until the battery voltage reached 2.75 V.
[0084] Charge Conditions at the Second and Subsequent Cycles
[0085] A constant-current charge was performed at a current of 1000 mA until the battery voltage reached 4.2 V, and then a constant-voltage charge was performed at a voltage of 4.2 V until the current value reached 50 mA.
[0086] Discharge Conditions at the Second and Subsequent Cycles
[0087] A constant-current discharge was performed at a current of 1000 mA until the battery voltage reached 2.75 V.
[0088] Subsequently, the initial charge-discharge efficiency and the cycle lifetime were determined by the following calculation methods. Table 1 shows the results.
[0000] Initial charge-discharge efficiency=(Discharge capacity at the first cycle)/(Charge capacity at the first cycle)100
[0089] Cycle lifetime: the number of cycles when the capacity retention ratio reached 90%
[0090] Herein, the capacity retention ratio is a value determined by dividing the discharge capacity at the nth cycle by the discharge capacity at the first cycle.
[0000]
TABLE 1
Negative electrode binder
Charge-discharge
Tetracarboxylic
Diamine
Diamine
cycle characteristics
dianhydride
(with hydroxyl group)
(without hydroxyl group)
Initial charge-
Battery
Structure
Molar ratio
Structure
Molar ratio
Structure
Molar ratio
discharge efficiency
Cycle lifetime
Battery A1
Formula (2)
100
Formula (1)
10
Formula (6)
90
88
95
Battery A2
Formula (2)
100
Formula (1)
30
Formula (6)
70
88
94
Battery A3
Formula (2)
100
Formula (1)
50
Formula (6)
50
88
88
Battery A4
Formula (3)
100
Formula (1)
10
Formula (6)
90
88
94
Battery A5
Formula (3)
100
Formula (1)
30
Formula (6)
70
88
94
Battery A6
Formula (3)
100
Formula (1)
50
Formula (6)
50
87
89
Battery B1
Formula (2)
100
—
0
Formula (6)
100
87
75
Battery B2
Formula (3)
100
—
0
Formula (6)
100
86
70
[0091] As is clear from the results shown in Table 1, the batteries A 1 to A 6 that used a diamine having a hydroxyl group had a charge-discharge cycle lifetime longer than that of the batteries B 1 and B 2 that used a diamine having no hydroxyl group. This is probably due to improved the adhesion between the polyimide resin and the negative electrode active material particles.
[0092] As is also clear from the comparison of the batteries A 1 to A 3 and the comparison of the batteries A 4 to A 6 , the cycle lifetime of lithium secondary batteries can be further lengthened by adjusting the molar ratio between the diamine having a hydroxyl group and the diamine having no hydroxyl group to be 10:90 to 30:70.
[0093] While detailed embodiments have been used to illustrate the present invention, to those skilled in the art, however, it will be apparent from the foregoing disclosure that various changes and modifications can be made therein without departing from the spirit and scope of the invention. Furthermore, the foregoing description of the embodiments according to the present invention is provided for illustration only, and is not intended to limit the invention. | A negative electrode for lithium secondary batteries includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is formed on the negative electrode current collector. The negative electrode active material layer contains a binder and negative electrode active material particles containing at least one of silicon and a silicon alloy. The binder is a polyimide resin formed by imidization of a tetracarboxylic acid or tetracarboxylic anhydride and a diamine. The diamine contains a diamine having at least one hydroxyl group. | 7 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to electronics, and, in particular, to memory devices having self-refresh modes.
[0003] 2. Description of the Related Art
[0004] In typical computer hardware architectures, an integrated circuit (IC) memory device chip is controlled by a separate IC memory controller chip that controls the writing of data to and the reading of data from the memory device during normal operations of the memory device. Some memory devices are capable of operating in a self-refresh mode in which the memory device maintains its stored data without any active command from the memory controller, such as when the memory controller is powered off.
[0005] For some memory devices, such as DDR1 and DDR2 registered dual in-line memory modules (RDIMMs) defined by Joint Electron Device Engineering Council (JEDEC) standards JESD79F and JESD79-2E, respectively, where DDR stands for “double data rate,” the memory device's RESET signal can be used to keep the memory device in self-refresh mode by holding the memory device's clock enable (CKE) line low while allowing the memory controller to be powered down. For other memory devices, such as DDR3 RDIMM memory devices defined by JEDEC standard JESD79-3C, asserting the RESET signal takes the memory device out of self-refresh mode. As such, when the memory controller is powered off, the RESET signal cannot be used to keep the memory device in self-refresh mode, thereby jeopardizing the integrity of the data stored in the memory device.
SUMMARY OF THE INVENTION
[0006] In one embodiment, the present invention is apparatus comprising a memory controller for controlling a memory device having a clock enable (CKE) input. The memory controller comprises first circuitry and second circuitry. The first circuitry is adapted to apply a first CKE signal to the CKE input during a normal operating mode. The second circuitry is adapted to apply a second CKE signal to the CKE input during a self-refresh operating mode. During the self-refresh operating mode, (i) the first circuitry is powered off and (ii) the second circuitry is powered on to drive the second CKE signal to a self-refresh signal level for the memory device.
[0007] In another embodiment, the present invention is a method for controlling a memory device having a clock enable (CKE) input. The method comprises (a) using first circuitry to apply a first CKE signal to the CKE input during a normal operating mode and (b) using second circuitry to apply a second CKE signal to the CKE input during a self-refresh operating mode. During the self-refresh operating mode, (i) the first circuitry is powered off and (ii) the second circuitry is powered on to drive the second CKE signal to a self-refresh signal level for the memory device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Other aspects, features, and advantages of the present invention will become more fully apparent from the following detailed description, the appended claims, and the accompanying drawings in which like reference numerals identify similar or identical elements.
[0009] FIG. 1 shows a simplified block diagram of memory circuitry 100 , according to one embodiment of the present invention.
DETAILED DESCRIPTION
[0010] As used in this specification, the term “powered off” refers to a state of an integrated circuit (IC) chip in which no power is applied to the chip. The term “powered on” refers to a state in which power is applied to the chip. The term “powering up” refers to a transition from the powered-off state to the powered-on state, while the term “powering down” refers to a transition from the powered-on state to the powered-off state.
[0011] FIG. 1 shows a simplified block diagram of memory circuitry 100 , according to one embodiment of the present invention. Memory circuitry 100 includes DDR3 RDIMM memory device 102 , memory controller 104 , power module 106 , and reset controller 108 . Memory controller 104 controls the writing of data to and the reading of data from memory device 102 . Power module 106 provides power to memory device 102 via power lines 112 and to memory controller 104 via main power lines 114 and backup power lines 116 . Reset controller 108 controls the operations of memory controller 104 via control lines 118 - 124 .
[0012] In addition to other circuitry not shown in FIG. 1 , memory controller 104 includes output buffers 126 , application logic 128 , and CKE power island 130 . Application logic 128 controls the operations of output buffers 126 , which drive signals into memory device 102 , including clock enable signal CKE via signal line 132 at the memory devices CKE input. CKE power island 130 includes isolation logic 134 and output buffers 136 . Isolation logic 134 controls the operations of output buffers 136 , whose outputs are connected to the same signal lines as the outputs of output buffers 126 , including clock enable signal CKE_prime, which is connected to the same signal line 132 that receives the CKE signal from a corresponding one of output buffers 126 . Note that, in general, connections could be made on the die or in the package routing. In general, the corresponding buffer 126 can be used to drive the CKE signal onto signal line 132 , when the corresponding buffer 136 is disabled, and vice versa. In addition, both corresponding buffers can be used simultaneously to drive equivalent output signals (i.e., the CKE and CKE_prime signals both high or both low) onto signal line 132 .
[0013] Although FIG. 1 shows memory circuitry 100 having separate components, in general, two or more of those components may be implemented in a single integrated system-on-a-chip (SOC).
[0014] Memory circuitry 100 supports two different modes of operation: normal operating mode and self-refresh operating mode. During the normal operating mode:
Memory device 102 and memory controller 104 are both fully powered on; Application logic 128 controls the operations of output buffers 126 to drive appropriate signals into memory device 102 . For example and in particular, in order for memory controller 104 to be able to write data to and read data from memory device 102 during the normal operating mode, application logic 128 controls output buffers 126 to toggle the CKE signal on signal line 132 ; and Reset controller 108 and isolation logic 134 ensure that output buffers 136 are disabled.
During the Self-Refresh Operating Mode:
[0000]
Memory device 102 is fully powered on;
Most but not all of memory controller 104 is powered off. For example and in particular, output buffers 126 and application logic 128 are powered off, while CKE power island 130 remains powered on; and
Reset controller 108 and isolation logic 134 control the operations of output buffers 136 to drive appropriate signals into memory device 102 . For example and in particular, in order for memory device 102 to remain in its self-refresh mode, output buffers 136 are controlled to drive the CKE_prime signal low on signal line 132 .
[0021] FIG. 1 indicates, via circled reference numbers, the sequence of operations to transition memory circuitry 100 from its normal operating mode into its self-refresh operating mode, and vice versa. In particular, memory circuitry 100 can be transitioned from its normal operating mode into its self-refresh operating mode (i.e., a power-down transition) by the following sequence of events:
(1) Transition is initiated by a system-level event, resulting in reset controller 108 asserting low-power-mode signal LOWPOWER_MODE on control line 118 . (2) In response to the assertion of the LOWPOWER_MODE signal, application logic 128 controls output drivers 126 to place memory device 102 into its self-refresh mode, including driving the CKE signal low on signal line 132 . (3) Application logic 128 activates CKE power island 130 . (4) Reset controller 108 enables output drivers 136 via control line 124 , which results in isolation logic 134 controlling output drivers 136 to drive the CKE_prime signal low on signal line 132 .
[0026] Note that, at this time, both corresponding output drivers 126 and 136 simultaneously drive signal line 132 low.
(5) Reset controller 108 asserts system-reset signal SYS_RESET via control line 120 . Asserting the SYS_RESET signal causes application logic 128 to place output buffers 126 into their initial state to ensure that output buffers 126 drive the CKE signal low. (6) Reset controller 108 asserts clock-disable signal CLOCK_DISABLE via control line 122 to disable the clocks (not shown) in memory controller 104 . (7) Reset controller 108 opens switch 138 to switch off power from power module 106 to memory controller 104 via main power lines 114 , which powers down most of memory controller 104 , including output buffers 126 and application logic 128 . Note that power module 106 continues to provide power to memory device 102 via power lines 112 and to CKE power island 130 via backup power lines 116 , such that isolation logic 134 controls output buffers 136 to drive the CKE_prime signal low to enable memory device 102 to remain in its self-refresh mode.
Note that the seven steps involved in the power-down transition may be implemented in a different order. For example, the order of steps (2) and (3) can be reversed. Note further that some of the steps may be optional. For example, step (5) is provided as a safety measure, but may be omitted in light of step (2).
[0030] In addition, referring to the same circled reference numbers in FIG. 1 , but in descending order (with the exception of steps (1) and (2)), memory circuitry 100 can be transitioned from its self-refresh operating mode back into its normal operating mode (i.e., a power-up transition) by the following sequence of events:
(7) Reset controller 108 closes switch 138 to switch back on power from power module 106 to memory controller 104 via main power lines 114 , which fully powers up memory controller 104 , including output buffers 126 and application logic 128 . Note that power module 106 continues to provide power to memory device 102 via power lines 112 and to CKE power island 130 via backup power lines 116 , such that isolation logic 134 controls output buffers 136 to continue to drive the CKE_prime signal low to enable memory device 102 to remain in its self-refresh mode. (6) Reset controller 108 de-asserts clock-disable signal CLOCK_DISABLE via control line 122 to re-enable the clocks (not shown) in memory controller 104 . (5) Reset controller 108 de-asserts system-reset signal SYS_RESET via control line 120 . De-asserting the SYS_RESET signal causes application logic 128 to re-initialize output buffers 126 for resumption of normal operations. Note that, at initialization, output buffers 126 drive the CKE signal low. At this time, both corresponding output drivers 126 and 136 simultaneously drive signal line 132 low. (4) Reset controller 108 disables output drivers 136 via control line 124 . (3) Application logic 128 deactivates CKE power island 130 . (1) Reset controller 108 de-asserts the LOWPOWER_MODE signal via control line 118 . (2) In response to the de-assertion of the LOWPOWER_MODE signal, application logic 128 controls output drivers 126 to release memory device 102 from its self-refresh mode for resumption of normal operations, including driving the CKE signal as needed.
Note that, here, too, the seven steps involved in the power-up transition may be implemented in a different order. For example, the order of step (3) can be implemented after steps (1) and (2).
[0038] Memory circuitry 100 enables memory controller 104 to be substantially powered down while maintaining the integrity of the data stored in memory device 102 .
[0039] In one implementation, each of elements 102 - 108 of FIG. 1 is a discrete electronic module mounted on a circuit board and interconnected via suitable board traces. Memory controller 104 may be part of a larger integrated circuit module that provides, in addition to the control of memory device 102 , other functions related to other system elements not shown in FIG. 1 . Similarly, power module 106 may provide power to other system elements not shown in FIG. 1 , including other memory devices.
[0040] Although the present invention has been described in the context of memory circuitry 100 of FIG. 1 having a single DDR3 RDIMM memory device, it will be understood that, in general, the present invention can be implemented for any suitable type of memory topology having one or more memory devices, where those memory devices can be RDIMMs, such as DDR1, DDR2, or DDR3 RDIMMs, or other suitable on-board devices.
[0041] The present invention may be implemented as (analog, digital, or a hybrid of both analog and digital) circuit-based processes, including possible implementation as a single integrated circuit (such as an ASIC or an FPGA), a multi-chip module, a single card, or a multi-card circuit pack. As would be apparent to one skilled in the art, various functions of circuit elements may also be implemented as processing blocks in a software program. Such software may be employed in, for example, a digital signal processor, micro-controller, or general-purpose computer.
[0042] Also for purposes of this description, the terms “couple,” “coupling,” “coupled,” “connect,” “connecting,” or “connected” refer to any manner known in the art or later developed in which energy is allowed to be transferred between two or more elements, and the interposition of one or more additional elements is contemplated, although not required. Conversely, the terms “directly coupled,” “directly connected,” etc., imply the absence of such additional elements.
[0043] It will be further understood that various changes in the details, materials, and arrangements of the parts which have been described and illustrated in order to explain the nature of this invention may be made by those skilled in the art without departing from the scope of the invention as expressed in the following claims.
[0044] The use of figure numbers and/or figure reference labels in the claims is intended to identify one or more possible embodiments of the claimed subject matter in order to facilitate the interpretation of the claims. Such use is not to be construed as necessarily limiting the scope of those claims to the embodiments shown in the corresponding figures.
[0045] It should be understood that the steps of the exemplary methods set forth herein are not necessarily required to be performed in the order described, and the order of the steps of such methods should be understood to be merely exemplary. Likewise, additional steps may be included in such methods, and certain steps may be omitted or combined, in methods consistent with various embodiments of the present invention.
[0046] Although the elements in the following method claims, if any, are recited in a particular sequence with corresponding labeling, unless the claim recitations otherwise imply a particular sequence for implementing some or all of those elements, those elements are not necessarily intended to be limited to being implemented in that particular sequence.
[0047] Reference herein to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the invention. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments necessarily mutually exclusive of other embodiments. The same applies to the term “implementation.” | To ensure that a memory device operates in self-refresh mode, the memory controller includes (1) a normal-mode output buffer for driving a clock enable signal CKE onto the memory device's CKE input and (2) a power island for driving a clock enable signal CKE_prime onto that same input. To power down the memory controller, the normal-mode output buffer drives signal CKE low, then the power island drives signal CKE_prime low, then the memory controller (except for the power island) is powered down. The power island continues to drive the memory device's CKE input low to ensure that the memory device stays in self-refresh mode while the memory controller is powered substantially off. To resume normal operations, the power module powers up the memory controller, then the normal-mode output buffer drives signal CKE low, then the power island is disabled, then the memory controller resumes normal operations of the memory device. | 8 |
BACKGROUND OF THE INVENTION
The present invention relates to drilling rigs and more particularly the erection of a high floor modular drilling rig.
In the drilling of exploratory wells such as oilwells, rigs are employed which can be transported to a site and assembled in place to perform the drilling operation. It is necessary to provide elevated drill floors to provide a space thereunder for equipment such as safety devices, blowout preventers, and the like. The rig must have a base suitable to support the rig on infirm soil so that the weight of the rig and the drilling equipment will be distributed over the base area for transfer to the earth.
According to the present invention, a drilling rig has a base for placement on the ground at a well site with a floor structure supported on parallel spaced legs pivotally attached between a floor structure and said base for allowing said floor structure to move from a low position on said base to an elevated position above said base by rotation of said legs to a vertical position. A pair of strong back towers are provided one on each side of the base near midway the length thereof with sheave means supported at the top of each tower with the axes thereof transverse the length of the base. Sheaves on each side of said floor structure have cables passing successively each sheave on said floor structure and over sheaves on the towers. Hydraulic means on each side of said base powers the cables to pull the floor structure to an elevated position adjacent said towers.
Preferably a pair of sheaves are mounted on each side of the base over which each cable passes. The hydraulic means comprise cylinders mounted on the base each connected to two ends of each cable for pulling the cables through the sheaves to raise the floor structure.
BRIEF DESCRIPTION OF THE DRAWINGS
The advantages and features of the improved modular rig of the present invention will be more readily appreciated by those of ordinary skill in the art as disclosure thereof is made in the following description by reference to the accompanying drawings, in which:
FIG. 1 is a side elevation of the improved modular drill rig embodying the present invention showing a base structure assembled and in place with support floors for the drawworks and most assembled and connected to the base structure with a strong back in place prior to raising the support floors with the upper end of the mast supported from a flat bed truck;
FIG. 2 is an enlarged partial side elevation of the modular drilling rig of FIG. 1 after erection;
FIG. 3 is a plan view of the support floor and base structure of the modular rig of the present invention; and
FIGS. 4, 5 and 6 illustrate an embodiment where hydraulic cylinders serve to elevate the support floors.
DETAILED DESCRIPTION
In the drawings, like reference characters designate like or corresponding parts throughout the several views. There is illustrated in FIG. 1, a modular drilling rig 10 shown as having a mast 12 supported at its upper end by a flat bed truck 14. The mast 12 is constructed from transportable sections 12a, b, c, d and e which are attached together. The mast 12 is pivotally coupled at 16 to the support floor 18 for rotation in the direction of arrow 20 to a vertical position. A drawworks assembly 22 is carried on a drawworks support floors 24.
A base structure 26 is formed from two halves 28 and 30 pinned together at 31. Base structure assembly 26 rests upon the earth surface for supporting the rig 10. Base structure 26 is constructed to distribute the weight of the rig on the earth surface. Distribution of weight through the base structure is important particularly when operating the rig at a site where the surface is soft or infirm.
A strong back 32 has legs 34 and 36 which are connected, respectively, to halves 28 and 30. Leg 34 is vertical and leg 36 extends at an angle from leg 34. Strong back 32 has such structure as shown in FIGS. 1 and 2 on both sides of base 26 and is braced laterally to provide rigid fixed but short towers for use in erecting floors 18 and 24. Assembly 32 supports sheaves 38 in an elevated position as shown in FIG. 1.
Drawworks support floor 24 is coupled to base structure 26 by means of two pair of parallel spaced pivotal links 40. Similarly, the mast support floor 18 is connected to the low structure 26 by means of two pair of parallel spaced pivotal links 42.
As will be hereinafter described, means are provided for moving support floor structures 18 and 24 to the elevated position illustrated in FIG. 2. The drawworks support floor 24 and links 40 allow the support floor 24 to move in the direction of arrow 44 from the position illustrated in FIG. 1 to the position illustrated in FIG. 2. Once in the elevated position, the support floor 24 is pinned at 46 to the strong back 32 and cross braces 48 are coupled between the base and flange 50 on the lower portion of the support floor 24.
In a similar manner, means are provided for rotating the support floor 18 and links 42 in the direction of arrow 52 from the position illustrated in FIG. 1 to the position illustrated in FIG. 2. This can be accomplished with the mast in the horizontal position illustrated in FIG. 1. Once elevated, the support floor 18 is pinned at 54 to the strong back 32. Cross braces 56 are connected between low structure 26 and a flange 58 on the bottom of support floor 18.
Next, the legs 62 and 64 of gin pole assembly 60 are supported respectively, from the support floors 18 and 24. This gin pole assembly 60 supports elevated sheaves 66. Sheaves 66 are used in rotating mast 12 in the direction of arrow 20 from the horizontal position illustrated in FIG. 1 to the vertical position illustrated in FIG. 2. Mast 12 can be raised by use of the sheaves 66 through the power of drawworks 22 and a wireline coupled to the mast 12.
Details of base structure 26 are illustrated in FIG. 3. Each of the halves 28 and 30 have side members 68 and 70, respectively. Side members 68 are coupled together by cross beam assemblies 72. Each of the side members 70 are coupled together by cross beam assemblies 74.
As can be seen in FIG. 2 the weight of mast 12 and drawworks 22 is supported from the elevated support floors 18 and 24. In this manner the weight of the mast and drawworks is distributed over the elevated supporting floors and in turn, is transmitted down through the links and cross braces to the base structure 26. By supporting mast 12 directly from the elevated support floor, the problems inherent in uneven distribution of weight by reason of the mast being supported from the low structure are minimized.
In FIGS. 4, 5 and 6, the system for raising the support floors 18 and 24 is illustrated wherein hydraulic cylinders 76 are mounted on the sides of the base structure 26. Hydraulic cylinders 76 are the double-acting type. Suitable conduits, valving, compressors and other equipment well known are provided to supply pressurized fluids to the cylinders for their selective operation. A pair of sheaves 78 is mounted to straddle each of the hydraulic cylinders 76. Sheaves 80 are mounted on the sides of the support floor 24.
As illustrated in FIG. 4 and the lower half of FIG. 5, a line 82 is attached to cylinder 76. Each of lines 82 may be stranded cable, chain or the like and the associated sheaves are selected to accommodate the particular type of line. Each line 82 has both its ends connected to a piston rod of one of the hydraulic cylinders 76. Lines 82 extend from the piston rod connection along cylinder 76 and passes around sheaves 78. Lines 82 then extend from sheaves 78 over sheaves 38 and are looped around sheave 80. By moving the piston rod from position 84a to position 84b (illustrated in FIG. 4) support floor 24 will move to the elevated position with links 40. Support floor 24 can then be pinned in place at 46 and cross braces 45 installed to rigidly support the drawworks in the elevated position.
During the process of raising support floor 24, assembly of the sections comprising the mast 12 can be simultaneously taking place. After raising of the support floor 24 for the drawworks assembly 22 is complete, work can begin to raise support floor 18. During this process of raising the support floor 18, assembly of the mast 12 can simultaneously take place and can even be completed after floor 18 is in the elevated position. In addition, during the process of raising support floor 18, work can begin on the drawworks, weather proofing, stairs and other equipment simultaneous with raising floor 18.
One configuration for raising support floor 18 is best illustrated in FIG. 6 and in the upper half of FIG. 5. To raise support floor 18, both ends of line 86 are coupled to the rod 84. Line 86 then passes over two pairs of sheaves 78 and 38. A pair of sheaves 88 are mounted one on each side of support floor 18 and has line 86 looped thereover.
As described with respect to support floor 24, support floor 18 is raised by actuating the hydraulic cylinder 76 to move the piston rod from the position 84a to the position 84b indicated by dotted lines. This action pulls support floor 18 from the position shown in solid lines to the position shown in dotted lines with links 42 vertical. Support floor 18 can then be pinned in position at 54, FIG. 2, and cross braces 56 installed to rigidly position the support floor 18 in the elevated position.
When the support floor 18 is in the elevated position, work can be started on the rotary table and other equipment on support floor 18 and assembly of the mast 12 can be completed. Thereafter, gin pole assembly 60 can be installed as previously described with respect to FIG. 2 and upon completion of assembly of the mast, the mast can be raised in a conventional manner to the vertical position illustrated in FIG. 2.
From the foregoing, it would be understood that the present invention relates to a modular drilling rig and method of erecting the floors while the mast is connected at its base to one of the elevated support floors. Preferably, the support floors are connected to the base of the rig by means of parallel spaced pivotal legs which allow movement of the support floors to the elevated position with the base of the mast coupled thereto and while the mast is lying in the horizontal position. Hydraulic cylinders are utilized to elevate the support floors preparatory to rotating the mast to its vertical operating position. This system has particular advantage over systems where the mast is supported directly from the base in that it allows work to be performed on the support floors in both the low and elevated positions and during assembly of the mast itself.
It is to be understood, of course, that the foregoing description relates to the preferred embodiments of the present invention and that numerous alterations and modifications of the invention can be accomplished without departing from the spirit and scope of the invention as defined by the accompanying claims. | A system for erecting elevated floors where a first support floor with a drawworks thereon is connected to one end of a base structure by two pair of parallel spaced pivotable links and a second support floor is coupled to the opposite end of the base structure and by two pair of parallel spaced pivotable links. In accordance with the invention a strong back is erected about midway of the length of the base forming a rigid frame and supporting elevated sheaves at each side of the base structure. A pair of cables are adapted to pass over said sheaves, one on each side of said base structure and connect first to said first floor for erection and then to said second floor for erection. | 4 |
A nickel-free phosphating process This invention relates to a process for phosphating metal surfaces with aqueous acidic phosphating solutions containing zinc, manganese and phosphate ions and also hydroxylamine in free or complexed form and/or m-nitrobenzenesulfonic acid or water-soluble salts thereof and to their use for pretreating the metal surfaces in preparation for subsequent lacquering, more particularly electrocoating. The process according to the invention may be used for the treatment of surfaces of steel, galvanized or alloy-galvanized steel, aluminium, aluminized or alloy-aluminized steel and, in particular, for the treatment of steel galvanized, preferably electrolytically, on one or both sides.
BACKGROUND OF THE INVENTION
The object of phosphating metals is to produce on the surface of the metals firmly intergrown metal phosphate coatings which, on their own, improve resistance to corrosion and, in combination with lacquers and other organic coatings, contribute towards significantly increasing lacquer adhesion and resistance to creepage on exposure to corrosive influences. Phosphating processes have been known for some time. Low-zinc phosphating processes are particularly suitable for pretreatment before lacquering. The phosphating solutions used in low-zinc phosphating have comparatively low contents of zinc ions, for example of 0.5 to 2 g/l. A key parameter in low-zinc phosphating baths is the ratio by weight of phosphate ions to zinc ions which is normally >8 and may assume values of up to 30.
It has been found that phosphate coatings with distinctly improved corrosion-inhibiting and lacquer adhesion properties can be obtained by using other polyvalent cations in the zinc phosphating baths. For example, low-zinc processes with additions of, for example, 0.5 to 1.5 g/l of manganese ions and, for example, 0.3 to 2.0 g/l of nickel ions are widely used as so-called trication processes for preparing metal surfaces for lacquering, for example for the cathodic electrocoating of car bodies.
RELATED ART
Unfortunately, the high content of nickel ions in the phosphating solutions of trication processes and the high content of nickel and nickel compounds in the phosphate coatings formed give rise to disadvantages insofar as nickel and nickel compounds are classified as critical from the point of view of pollution control and hygiene in the workplace. Accordingly, low-zinc phosphating processes which, without using nickel, lead to phosphate coatings comparable in quality with those obtained by nickel-containing processes have been described to an increasing extent in recent years. The accelerators nitrite and nitrate have also encountered increasing criticism on account of the possible formation of nitrous gases. In addition, it has been found that the phosphating of galvanized steel with nickel-free phosphating baths leads to inadequate protection against corrosion and to inadequate lacquer adhesion if the phosphating baths contain relatively large quantities (>0.5 g/l) of nitrate.
For example, DE-A-39 20 296 describes a nickel-free phosphating process which uses magnesium ions in addition to zinc and manganese ions. In addition to 0.2 to 10 g/l of nitrate ions, the corresponding phosphating baths contain other oxidizing agents acting as accelerators selected from nitrite, chlorate or an organic oxidizing agent.
EP-A-60 716 discloses low-zinc phosphating baths which contain zinc and manganese as essential cations and which may contain nickel as an optional constituent. The necessary accelerator is preferably selected from nitrite, m-nitrobenzenesulfonate or hydrogen peroxide. A dependent claim is directed to the use of 1 to 10 g/l of nitrate; all the Examples mention 4 g/l of nitrate.
EP-A-228 151 also describes phosphating baths containing zinc and manganese as essential cations. The phosphating accelerator is selected from nitrite, nitrate, hydrogen peroxide, m-nitrobenzenesulfonate, m-nitrobenzoate or p-nitrophenol. Dependent claims specify a nitrate content of 5 to around 15 g/l and an optional nickel content of 0.4 to 4 g/l. The corresponding Examples all mention both nickel and nitrate. The main point of this application is that it provides chlorate-free phosphating processes. The same applies to EP-A-544 650.
The phosphating process disclosed in WO 86/04931 is nitrate-free. In this case, the accelerator system is based on a combination of 0.5 to 1 g/l of bromate and 0.2 to 0.5 g/l of m-nitrobenzenesulfonate. Only zinc is mentioned as an essential polyvalent cation, nickel, manganese or cobalt being mentioned as other optional cations. Besides zinc, the phosphating solutions preferably contain at least two of these optional metals. EP-A-36 689 teaches the use of preferably 0.03 to 0.2% by weight of nitrobenzenesulfonate in combination with, preferably, 0.1 to 0.5% by weight of chlorate in phosphating baths of which the manganese content is 5 to 33% by weight of the zinc content.
WO 90/12901 discloses a chlorate- and nittrite-free process for the production of nickel- and manganese-containing zinc phosphate coatings on steel, zinc and/or alloys thereof by spray, spray-dip or dip coating with a solution containing
______________________________________0.3 to 1.5 g/l of zinc (II),0.01 to 2.0 g/l of manganese (II),0.01 to 0.8 g/l of iron (II),0.3 to 2.0 g/l of nickel (II),10.0 to 20.0 g/l of phosphate ions,2.0 to 10.0 g/l of nitrate ions and0.1 to 2.0 g/l of an organic oxidizing agent (for example m-nitrobenzenesulfonate),______________________________________
the aqueous solution having a free acid content of 0.5 to 1.8 points and a total acid content of 15 to 35 points and Na + being present in the quantity required to establish the free acid content.
DE-A-40 13 483 describes phosphating processes with which it is possible to obtain anti-corrosion properties comparable with those achieved in trication processes. These processes are nickel-free and, instead, use copper in low concentrations of 0.001 to 0.03 g/l. Oxygen and/or other oxidizing agents with an equivalent effect are used to oxidize the divalent iron formed during the pickling of steel surfaces into the trivalent stage. Nitrite, chlorate, bromate, peroxy compounds and organic nitro compounds, such as nitrobenzenesulfonate, are mentioned as examples of the other oxidizing agents. German patent application P 42 10 513.7 modifies this process to the extent that hydroxylamine, salts or complexes thereof are added in a quantity of 0.5 to 5 g/l of hydroxylamine to modify the morphology of the phosphate crystals formed.
The use of hydroxylamine and/or its compounds to influence the form of phosphate crystals is known from a number of publications. EP-A-315 059, in mentioning one particular effect of using hydroxylamine in phosphating baths, points out that the phosphate crystals are formed in a desirable columnar or nodular form on steel even when the concentration of zinc in the phosphating bath exceeds the range typical of low-zinc processes. It is possible in this way to operate the phosphating baths with zinc concentrations of up to 2 g/l and with ratios by weight of phosphate to zinc of as low as 3.7. Although advantageous cation combinations of these phosphating baths are not discussed in any detail, nickel is used in every Example. Nitrates and nitric acid are also used in the Examples although the specification advises against the presence of nitrate in relatively large quantities.
EP-A-321 059 relates to zinc phosphating baths which, in addition to 0.1 to 2.0 g/l of zinc and an accelerator, contain 0.01 to 20 g/l of tungsten in the form of a soluble tungsten compound, preferably an alkali metal or ammonium tungstate or silicotungstate, an alkaline earth metal silicotungstate or boro- or silicotungstic acid. The accelerator is selected from nitrite, m-nitrobenzenesulfonate or hydrogen peroxide. Nickel in quantities of 0.1 to 4 g/l and nitrate in quantities of 0.1 to 15 g/l are mentioned inter alia as optional constituents.
DE-C-27 39 006 describes a phosphating process for surfaces of zinc or zinc alloys which is free from nitrate and ammonium ions. In addition to an essential content of zinc of 0.1 to 5 g/l, 1 to 10 parts by weight of nickel and/or cobalt per part by weight of zinc are necessary. Hydrogen peroxide is used as the accelerator. From the point of view of hygiene in the workplace and pollution control, cobalt is not an alternative to nickel.
BRIEF DESCRIPTION OF THE INVENTION
The problem addressed by the present invention was to provide phosphating baths which would be free from ecologically and physiologically unsafe nickel and equally unsafe cobalt, would not contain any nitrite and, at the same time, would have a greatly reduced nitrate content and, preferably, would be free from nitrate. In addition, the phosphating baths would be free from copper which is problematical in the effective concentration range of 1 to 30 ppm according to DE-A-40 13 483.
The problem stated above has been solved by a process for phosphating metal surfaces with aqueous acidic phosphating solutions containing zinc, manganese and phosphate ions and, as accelerator, hydroxylamine or a hydroxylamine compound and/or m-nitrobenzenesulfonic acid or water-soluble salts thereof, characterized in that the metal surfaces are contacted with a phosphating solution which is free from nickel, cobalt, copper, nitrite and oxo-anions of halogens and which contains 0.3 to 2 g/l of Zn(II), 0.3 to 4 g/l of Mn(II), 5 to 40 g/l of phosphate ions, 0.1 to 5 g/l of hydroxylamine in free or complexed form and/or 0.2 to 2 g/l of m-nitrobenzenesulfonate and at most 0.5 g/l of nitrate ions, the Mn content amounting to at least 50% of the Zn content.
DETAILED DESCRIPTION OF THE INVENTION
The fact that the phosphating baths are meant to be free from nickel, copper, nitrite and oxo-anions of halogens means that these elements or ions are not intentionally added to the phosphating baths. However, it is not possible in practice to prevent constituents such as these being introduced in traces into the phosphating baths through the material to be treated, the mixing water or through the ambient air. In particular, it is not possible to prevent nickel ions being introduced into phosphating solution in the phosphating of steel coated with zinc/nickel alloys. However, one of the requirements which the phosphating baths according to the invention are expected to satisfy is that, under technical conditions, the concentration of nickel in the baths should be less than 0.01 g/l and, more particularly, less 0.0001 g/l. In a preferred embodiment, no nitrate is added to the baths. However, the baths may well have the nitrate content of the local drinking water (a maximum of 50 mg/l under German legislation on drinking water) or higher nitrate contents caused by evaporation. However, the baths according to the invention should have a maximum nitrate content of 0.5 g/l and preferably contain less than 0.1 g/l of nitrate.
Hydroxylamine may be used in the form of a free base, as a hydroxylamine complex or in the form of hydroxylammonium salts. If free hydroxylamine is added to the phosphating bath or to a phosphating bath concentrate, it will largely be present as hydroxylammonium cation on account of the acidic character of these solutions. Where the hydroxylamine is used in the form of hydroxylammonium salt, the sulfates and phosphates are particularly suitable. Among the phosphates, the acidic salts are preferred by virtue of their better solubility. Hydroxylamine or its compounds are added to the phosphating bath in such quantities that the calculated concentration of free hydroxylamine is between 0.1 and 5 g/l and, more particularly, between 0.4 and 2 g/l. It has proved to be favorable to select the hydroxylamine concentration in such a way that the ratio of the sum of the zinc and manganese concentrations to the hydroxylamine concentration (in g/l) is 1.0 l to 6.0:1 and preferably 2.0 l to 4.0:1.
Similarly to the disclosure of EP-A-321 059, the presence of soluble compounds of hexavalent tungsten also affords advantages in regard to corrosion resistance and lacquer adhesion in the phosphating baths according to the invention containing hydroxylamine or hydroxylamine compounds although, in contrast to the teaching of EP-A-321 059, the accelerators nitrite or hydrogen peroxide need not be used in the phosphating process according to the invention. Phosphating solutions additionally containing 20 to 800 mg/l and preferably 50 to 600 mg/l of tungsten in the form of water-soluble tungstates, silicotungstates and/or borotungstates may be used in the phosphating processes according to the invention. The anions mentioned may be used in the form of their acids and/or their ammonium, alkali metal and/or alkaline earth metal salts. m-Nitrobenzenesulfonate may be used in the form of the free acid or in the form of water-soluble salts. "Water-soluble" salts in this context are salts which dissolve in the phosphating baths to such an extent that the necessary concentrations of 0.2 to 2 g/l of m-nitrobenzenesulfonate are reached. The alkali metal salts, preferably the sodium salts, are especially suitable for this purpose. The phosphating baths preferably contain 0.4 to 1 g/l of m-nitrobenzenesulfonate.
A ratio of 1:10 to 10:1 between the more reductive hydroxylamine and the more oxidative m-nitrobenzenesulfonate can lead to particular advantages in regard to layer formation, particularly in regard to the shape of the crystals formed. However, it is also possible and--in the interests of simplified bath control--preferred for the phosphating baths to contain either hydroxylamine or m-nitrobenzenesulfonic acid.
In the case of phosphating baths which are meant to be suitable for various substrates, it has become standard practice to add free and/or complexed fluoride in quantities of up to 2.5 g/l of total fluoride, including up to 800 mg/l of free fluoride. The presence of fluoride in quantities of this order is also of advantage for the phosphating baths according to the invention. In the absence of fluoride, the aluminium content of the bath should not exceed 3 mg/l. In the presence of fluoride, higher Al contents are tolerated as a result of complexing providing the concentration of the non-complexed Al does not exceed 3 mg/l.
The ratio by weight of phosphate ions to zinc ions in the phosphating baths may vary within wide limits providing it remains between 3.7 l and 30:1. A ratio by weight of 10 l to 20:1 is particularly preferred. The contents of free acid and total acid are known to the expert as further parameters for controlling phosphating baths. The method used to determine these parameters in the present specification is described in the Examples. Free acid contents of 0.3 to 1.5 points in the phosphating of parts and up to 2.5 points in coil phosphating and total acid contents of around 15 to 25 points are in the usual range and are suitable for the purposes of the present invention.
The manganese content of the phosphating bath should be between 0.3 and 4 g/l because lower manganese contents do not have a positive effect on the corrosion behavior of the phosphate coatings while higher manganese contents have no other positive effect. Contents of 0.3 to 2 g/l are preferred, contents of 0.5 to 1.5 g/l being particularly preferred. According to EP-A-315 059, the zinc content of phosphating baths containing hydroxylamine as sole accelerator is preferably adjusted to values of 0.45 to 1.1 g/l, the zinc content of phosphating baths containing m-nitrobenzenesulfonate as sole accelerator preferably being adjusted to values of 0.6 to 1.4 g/l. However, due to the erosion encountered in the phosphating of zinc-containing surfaces, the actual zinc content of the bath can rise in operation to levels of up to 2 g/l. It is important in this connection to ensure that the manganese content amounts to at least 50% of the zinc content because otherwise inadequate corrosion prevention properties are obtained. In principle, the form in which the zinc and manganese ions are introduced into the phosphating baths is of no consequence. However, to satisfy the conditions according to the invention, the nitrites, nitrates and salts with oxo-anions of halogens of these cations cannot be used. The oxides and/or carbonates are particularly suitable for use as the zinc and/or manganese source. In addition to the divalent cations mentioned, phosphating baths normally contain sodium, potassium and/or ammonium ions which are used to adjust the parameters free acid and total acid. Ammonium ions can also be formed by degradation of the hydroxylamine.
When the phosphating process is applied to steel surfaces, iron passes into solution in the form of iron(II) ions. Since the phosphating baths according to the invention do not contain any substances with a strong oxidizing effect on iron(II), most of the divalent iron changes into the trivalent state as a result of oxidation with air so that it can precipitate as iron(III) phosphate. Accordingly, iron(II) contents distinctly exceeding those present in baths containing oxidizing agents can build up in the phosphating baths according to the invention. Iron(II) concentrations up to 50 ppm are normal in this regard although concentrations of up to 500 ppm can occur briefly during the production process. Iron(II) concentrations of this order are not harmful to the phosphating process according to the invention. In addition, where the phosphating baths are prepared with hard water, they may contain the cations Mg(II) and Ca(II) responsible for hardness in a total concentration of up to 7 mmoles/l.
The process according to the invention is suitable for the phosphating of surfaces of steel, galvanized or alloy-galvanized steel, aluminium, aluminized or alloy-aluminized steel. Hydroxylamine-containing baths are particularly intended for the treatment of steel galvanized, preferably electrolytically, on one or both sides.
The materials mentioned may even be present alongside one another, as is becoming increasingly normal in automobile construction. The process is suitable for dip, spray or spray/dip application. It may be used in particular in automobile construction where treatment times of 1 to 8 minutes are normal. However, it may also be used for coil phosphating in steelworks where the treatment times are between 5 and 12 seconds. As in other known phosphating baths, suitable bath temperatures are between 30° and 70° C., the temperature range from 40° to 60° C. being preferred.
The phosphating process according to the invention is intended for the formation of a low-friction coating for forming operations and, in particular, for the treatment of the metal surfaces mentioned before lacquering, for example before cathodic electrocoating, as is normally applied in automobile construction. The phosphating process may be regarded as one of the steps of the normal pretreatment cycle. In this cycle, phosphating is normally preceded by the steps of cleaning/degreasing, intermediate rinsing and activation, activation normally being carried out with activators containing titanium phosphate. Phosphating in accordance with the invention may be followed by a passivating aftertreatment, optionally after intermediate rinsing. Treatment baths containing chromic acid are widely used for passivating aftertreatments. However, in the interests of pollution control and hygiene in the workplace and also for waste-management reasons, there is a tendency to replace these chromium-containing passivating baths by chromium-free treatment baths. Pure inorganic bath solutions based in particular on zirconium compounds and even organic/reactive bath solutions, for example based on polyvinyl phenols, are known for this purpose. In general, intermediate rinsing with deionized water is carried out between the passivation step and the electrocoating process by which it is normally followed.
EXAMPLES 1 TO 7
Comparison Examples 1 and 2
The phosphating processes according to the invention using hydroxylamine compounds and comparison processes were tested on steel plates (St 1405) and on steel plates electrogalvanized on both sides (ZE), as used in automobile construction. The following sequence of process steps typically applied in body manufacture was carried out (by dip coating or spray coating):
1. For dip coating: cleaning with an alkaline cleaner (Ridoline® C 1250 I, a product of Henkel KGaA), 2% solution in municipal water, 55° C., 4 minutes.
For spray coating: cleaning with an alkaline cleaner (Ridoline® C1206, a product of Henkel KGaA), 0.5% solution in municipal water, 55° C., 2 minutes.
2. Spray or dip rinsing with municipal water, room temperature, 1 minute.
3. Dip activation with an activator containing titanium phosphate (Fixodine® 9112, a product of Henkel KGaA), 0.3% solution in deionized water, room temperature, 1 minute.
4. Phosphating with the phosphating baths according to Table 1. Apart from the cations mentioned in Table 1, the phosphating baths merely contained sodium ions to adjust the free acid content. The baths did not contain any nitrite or any oxo-anions of halogens.
The free acid point count is understood to be the consumption in ml of 0.1 normal sodium hydroxide which is required to titrate 10 ml of bath solution to a pH value of 3.6. Similarly, the total acid point count indicates the consumption in ml to a pH value of 8.2.
5. Spray or dip rinsing with municipal water, room temperature, 1 minute.
6. Spray or dip passivation with a chromate-containing passivating agent (Deoxylyte® 41, a product of Henkel KGaA), 0.14% solution in deionized water, 40° C., 1 minute.
7. Dip or spray rinsing with deionized water.
8. Blow drying with compressed air.
The area-based weight ("coating weight") was determined by dissolution in 5% chromic acid solution in accordance with DIN 50 942, Table 6. Corrosion tests were carried out by the VDA-Wechselklimatest ("alternating climate test") 621-415 with an electrocoating (EP) primer (KTL-hellgrau, a product of BASF, FT 85-7042); and in some cases with a complete multicoat lacquer finish (finishing lacquer: Alpine White, VW). Lacquer creepage (mm) was determined in accordance with DIN 53167 while chipping behavior was determined by the VW test (K-values: best value K=1, worst value K=10), in each case after 10 one-week test cycles. The results are set in Table 2.
TABLE 1__________________________________________________________________________Phosphating baths Bath No.Parameter Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Ex. 6 Ex. 7 Comp. 1 Comp. 2__________________________________________________________________________Zn(II) (g/l) 1 0.9 1 1 1 1 1 1 1Mn(II) (g/l) 0.8 0.5 0.8 0.8 0.8 0.8 0.8 0.8 0.5PO.sub.4.sup.3- (g/l) 14.5 12.5 14 14 14 14 14 14.5 12.5W(VI) (ppm) (as 0 0 25 50 100 200 500 0 0Na tungstate)Total F.sup.- (g/l) 1 1 0.14 0.14 0.14 0.14 0.14 1 1Free acid (points) 1.1 1.0 0.9 0.9 0.9 0.9 0.9 1.1 1.0Total acid (points) 22 19.8 21.7 21.7 21.7 21.7 21.7 22 19.8Hydroxyl ammonium 2 1.7 2 2 2 2 2 2 1.7sulfate (g/l)Nitrate (g/l) -- -- -- -- -- -- -- 2 2Temperature (°C.) 53 51 53 53 53 53 53 53 51Application Dip Spray Spray Spray Spray Spray Spray Dip Spray (1 bar) (1 bar) (1 bar) (1 bar) (1 bar) (1 bar) (1 bar)Time (minutes) 3 1.5 1.5 1.5 1.5 1.5 1.5 3 1.5__________________________________________________________________________
TABLE 2__________________________________________________________________________Coating weights and corrosion results Coating EC primer Full lacquer finishTreated in weight Lacquer Chipping Lacquer Chippingacc. with Material (g/m.sup.2) creepage (mm) K-value creepage (mm) K-value__________________________________________________________________________Example 1 ZE 4.80 2.5 7-8 2.0 3-4Example 2 ZE 3.70 2.5 5-6 1.4 2 Steel 2.70 0.6 6 1.0 4Example 3 ZE 1.9 8 Steel 1.1 6Example 4 ZE 1.6 6 Steel 0.8 5-6Example 5 ZE 1.9 5 Steel 0.9 6-7Example 6 ZE 2.2 5 Steel 1.2 7Example 7 ZE 2.3 2 Steel 1.2 6-7Comparison 1 ZE 2.60 2.9 10 3.2 8Comparison 2 ZE 3.20 2.8 8-9 2.7 8 Steel 3.40 1.3 6-7 1.8 5-6__________________________________________________________________________
EXAMPLE 8
Comparison Examples 3 and 4
Process sequence (dip)
1. Cleaning with an alkaline cleaner (Ridoline® C 1250 I, a product of Henkel KGaA), 2% solution in municipal water, 55° C., 4 minutes.
2. Rinsing with municipal water, room temperature, 1 minute.
3. Activation with a liquid activator containing titanium phosphate (Fixodine® L, a product of Henkel KGaA), 1% solution in deionized water, room temperature, 1 minute.
4. Phosphating with the phosphating baths according to Table 3, 53° C., 3 minutes. Apart from the cations mentioned in Table 3, the phosphating baths merely contained sodium ions to adjust the free acid content. The bath of Example 8 did not contain any nitrite or nitrate or any oxo-anions of halogens.
5. Rinsing with municipal water, room temperature, 1 minute.
6. Passivation with a chromium-free passivating agent based on zirconium fluoride (Deoxylyte® 54 NC, a product of Henkel KGaA), 0.25% solution in deionized water, 40° C., 1 minute.
7. Rinsing with deionized water.
8. Blow drying with compressed air.
(Materials and definition of free acid and total acid as for Examples 1 to 7).
Coating weights were determined by dissolution in 5% chromic acid solution. Corrosion tests were carried out by the VDA-Wechselklimatest 621-415 both with EC primer only (ED 12 MB, a product of PPG) and with a complete multicoat lacquer finish (EC as above, filler: one-component high-solid PU filler grey, finishing lacquer: DB 744 metallic basecoat and clearcoat). Lacquer creepage (mm) was evaluated after 10 one-week test cycles. A ball-projection test was also carried out in accordance with the Mercedes-Benz standard based on DIN 53230 (6 bar corresponding to 250 km/h), evaluation at a substrate temperature of -20° C. The area damaged in mm 2 (Mercedes-Benz standard: max. 5) and the degree of rust (best value=0, worst value=5, Mercedes-Benz standard: max. 2) were evaluated. The results are set out in Table 4.
TABLE 3______________________________________Phosphating bathsParameter Example 8 Comparison 3 Comparison 4______________________________________Zn(II) (g/l) 1.0 1.0 1.0Mn(II) (g/l) 0.8 1.0 0.8Ni(II) (g/l) -- 0.9 0.8PO.sub.4 .sup.3- (g/l) 14.5 14.6 13.5Total F.sup.- (g/l) 0.8 0.8 0.8Free acid (points) 1.0 1.0 1.0Total acid (points) 22 23 24.0Hydroxylammonium 2 -- 2sulfate (g/l)Nitrite (mg/l) -- 100 --Nitrate (g/l) -- 2 2______________________________________
TABLE 4__________________________________________________________________________Coating weights and corrosion results Full lacquer finish Coating EC Primer Ball projection testTreated in weight Lacquer Lacquer Area damageacc. with Material (g/m.sup.2) creepage (mm) creepage (mm) (mm.sup.2) Degree of rust__________________________________________________________________________Example 3 ZE 3.50 1.0 3-4 1-2 Steel 2.80 1.5 1.0 4 1-2Comparison 3 ZE 2.50 0.8 4-5 0-1 Steel 3.0 1.0 0.5 3 1-2Comparison 4 ZE 1.90 <0.5 4 1 Steel 2.0 1.0 0.8 5 0__________________________________________________________________________
EXAMPLES 9 TO 12
Comparison Examples 5 to 7
The phosphating processes according to the invention using m-nitrobenzenesulfonate and comparison processes were tested on steel plates and on steel plates electrogalvanized on both sides (ZE), as used in automobile construction. The following sequence of process steps typically applied in body manufacture was carried out (by dip coating):
1. Cleaning with an alkaline cleaner (Ridoline® 1558, a product of Henkel KGaA), 2% solution in municipal water, 55° C., 5 minutes.
2. Rinsing with municipal water, room temperature, 1 minute.
3. Dip activation with a liquid activator containing titanium phosphate (Fixodine® L, a product of Henkel KGaA), 0.5% solution in deionized water, room temperature, 1 minute.
4. Phosphating with the phosphating baths according to Table 5 (prepared with deionized water, unless otherwise indicated). Apart from the cations mentioned in Table 1, the phosphating baths merely contained sodium ions to adjust the free acid content. The baths did not contain any nitrite or any oxo-anions of halogens.
The free acid point count is understood to be the consumption in ml of 0.1 normal sodium hydroxide which is required to titrate 10 ml of bath solution to a pH value of 3.6. Similarly, the total acid point count indicates the consumption in ml to a pH value of 8.5.
5. Rinsing with municipal water, room temperature, 1 minute.
6. Passivation with a chromate-containing passivating agent (Deoxylyte® 41, a product of Henkel KGaA), 0.1% solution in deionized water, 40° C., 1 minute.
7. Rinsing with deionized water.
8. Blow drying with compressed air.
The area-based weight ("coating weight") was determined by dissolution in 5% chromic acid solution in accordance with DIN 50 942. Corrosion tests were carried out by the VDA-Wechselklimatest ("alternating climate test") 621-415 with an electrocoating (EP) primer (KTL-hellgrau, a product of BASF, FT 85-7042). Lacquer creepage (mm) was determined in accordance with DIN 53167 while chipping behavior was determined by the VW test VW.P3.17.1 (K-values: best value K=1, worst value K=10). The results are set out in Table 5.
TABLE 5__________________________________________________________________________Phosphating baths and test results (use of m-nitrobenzenesulfonate)Parameter Example 9 Example 10 Example 11 Example 12 Comp. 5 Comp. 6 Comp. 7__________________________________________________________________________Zn(II) (g/l) 1.0 1.0 0.9 1.0 1.0 1.0 1.0Mn(II) (g/l) 0.8 0.8 0.8 0.8 0.8 0.8 0.2Ni(II) (g/l) -- -- -- -- 0.7 -- --PO.sub.4.sup.3- (g/l) 13.7 13.7 14.5 13.7 13.7 13.7 13.7SiF.sub.6.sup.2- (g/l) 0.95 0.95 0.95 0.95 0.95 0.95 0.95F.sup.- 0.22l) 0.22 0.22 0.22 0.22 0.22 0.22m-Nitrobenzene- 0.5 0.7 1.0 0.7 0.7 0.5 0.7sulfonate (g/l)NO.sub.3.sup.- (g/l) -- -- -- 0.03*) -- 2 --Free acid 1.2 1.2 1.2 1.2 1.2 1.2 1.2(points)Total acid 20.0 20.0 22.0 20.0 21.0 20.0 20.0(points)Electrogalvan-ized steelplateCoating weight 3.7 3.5 3.3.sup.a) 3.0 3.9 2.6 2.5(g/m.sup.2)Lacquer creep- 2.5 2.3 2.1 2.9 2.3 6.0 5.0age (mm)Chipping 7 6 6 7 5 10 9value (K)Steel plateCoating weight 2.8 2.6 2.5 2.7 2.8 2.5 2.5(g/m.sup.2)Lacquer creep- 1.0 0.9 1.1 0.9 0.8 1.1 1.1age (mm)Chipping 5 6 5-6 5-6 5-6 6 6value (K)__________________________________________________________________________ *Nitrate content from process water used for preparation .sup.a) Aged strip | A process for phosphating surfaces of steel, galvanized or alloy-galvanized steel, aluminum, aluminized or alloy-aluminized steel. The process is particularly useful for treating metal surfaces which are to be cathodic electrocoated. The process uses a nickel, cobalt, copper, nitrite and oxo-anion of halogen free phosphating solution containing 0.3 to 2.0 g/l Zn(II), 0.3 to 4 g/l Mn(II), 5 to 40 g/l phosphate ions and at least one of 0.5 to 5 g/l hydroxylamine and 0.2 to 2 g/l m-nitrobenzene sulfonate wherein the ratio by weight of Zn(II) to Mn(II) is not greater than 2. | 2 |
BACKGROUND OF THE INVENTION
1. Technical Field of the Invention
The present invention relates to wideband channelization techniques, and more particularly, to a method for using subsampled discrete fourier transform filter banks to channelize wideband signals.
2. Description of Related Art
Radio receivers requiring simultaneous reception of multiple radio channels require the extraction of a number of radio channels from a wideband signal. Such receivers may include macro base stations, micro base stations, pico base stations and others. These types of receivers typically operate according to a frequency reuse plan that effectively restricts each base station to a regularly spaced subset of all available channels.
In one prior art implementation, individual radio channels are extracted from a wideband signal utilizing a DFT (discrete fourier transform) filter bank. The problem with existing DFT-channelizers is that they extract every channel from the wideband radio signal. This requires a great deal of arithmetic operations by the channelizer and increases the cost/complexity of the receiver. Since each base station is only utilizing a regularly spaced subset of all available channels. Accordingly, a more efficient, less complex method for extracting radio channels from a wideband signal is desired.
SUMMARY OF THE INVENTION
The present invention overcomes the foregoing and other problems with a channelizer for use in processing a wideband signal within a receiver. A wideband signal is initially processed by a subsampled filter bank to extract a selected number of regularly spaced channels from the plurality of channels within the received wideband signal. The subsampled DFT-channelizer consists of a bank of polyphase filters for extracting all of the potential channels from the wideband signal (M channels in all). The outputs of the polyphase filters are then time aliased to generate a second sequence of signals equal in number to the selected number of regularly spaced channels M/L desired channels).
This second sequence of signals are processed by an ##EQU1## inverse discrete fourier transform resulting in M/L bandpass signals. The inverse discrete fourier transform coefficients are then mixed with a sequence of carrier signals to shift these bandpass signals to baseband, resulting in extraction of M/L regularly spaced channels from the wideband signal. This system significantly decreases the amount of required processing power. In the system in accordance with the present invention, the number of arithmetic operations necessary to produce the desired channels are significantly less than the number of arithmetic operations presently required to extract every channel.
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present invention, reference is made to the following detailed description taken in conjunction with the accompanying drawings wherein:
FIG. 1 is a block diagram of a generic wideband receiver;
FIG. 2 is a functional diagram of a single branch of a DFT-channelizer;
FIG. 3 is a diagram of a DFT-channelizer; and
FIG. 4 is a block diagram of a subsampled DFT-channelizer.
DETAILED DESCRIPTION OF THE INVENTION
Referring now to the drawings, and more particularly to FIG. 1, there is illustrated a block diagram of a generic wideband receiver. A transmitted wideband signal is received at an antenna 5. Through several stages of mixing and filtering (shown generally at 10), the signal is processed to a desired frequency band, and is then mixed down by a mixer 15 to a baseband signal x(t) with relatively wide bandwidth for input to a wideband analog-to-digital converter 20. The analog-to-digital converter 20 converts the analog wideband signal x(t) to a digital wideband signal x(n) which is then processed by a digital channelizer 25 to extract the various radio channels 30. The prior art DFT-channelizer 25 (as shown in FIG. 3) provides a computationally efficient manner for extracting every channel within the wideband signal x(n).
Referring now to FIG. 2, there is illustrated a functional diagram of one branch of a DFT-channelizer H o (w) represents a real, lowpass FIR filter. Every other filter within the filter bank is a modulated version of this lowpass prototype. Thus, ##EQU2## O≦i≦M-1, M equals the number of channels. Note that H i (w) represents a bandpass complex-valued filter centered on the discrete time frequency ##EQU3## or equivalently centered around the continuous time frequency ##EQU4## (F s is the sampling frequency of the A/D converter), M equals the total number of channels between {-F s /2, +F s /2}). In other words there are exactly M equal bandwidth filters in the filter bank, spaced apart by ##EQU5## The DFT-channelizer of FIG. 3 is valid only when M is an integer multiple of the downsampling factor N (i.e., M=N×K; where K is some positive integer). The DFT-channelizer can be efficiently implemented using an inverse discrete fourier transform (IDFT) and the polyphase decomposition of the lowpass prototype filter H o (n). This implementation is typically referred to as a DFT-channelizer and is illustrated in FIG. 3. ##EQU6##
Referring now to FIG. 3, there is illustrated a block diagram of a DFT-channelizer. In FIG. 3, the E i (z)s represent the polyphase components of H o (z). Thus, ##EQU7##
The main limitation of a prior art DFT-channelizer is that it channelizes every channel in the frequency range ##EQU8## even though only a subset of these channels might actually be needed. For example, in most cellular systems using a 7/21 frequency reuse plan, each base station only uses one out of every seven radio channels. Thus, a receiver would only need to channelize every 7th channel.
Referring now to FIG. 4, there is illustrated a block diagram of a subsampled DFT-channelizer of the present invention. For the subsampled DFT-channelizer, it is assumed that only every L-th output channel must be computed and that the total number of channels M is an integer multiple of L, thus
M=L×r
where r is some positive integer.
From the discrete wideband signal x(n), the subsampled DFT-channelizer computes only the desired channels {c o [n],c L [n],c 2L [n], . . . ,c M-L [n]}.
Comparing FIG. 4 to FIG. 3, we see that the subsampled DFT-channelizer replaces the M-point DFT in the DFT-channelizer with a time-aliasing block and an ##EQU9## IDFT. The combined complexity of the time-aliasing block and ##EQU10## IDFT is much smaller than the complexity of the M-point IDFT.
The outputs of the time-aliasing block are formed from the output of the polyphase filters according to ##EQU11## The Q outputs of the ##EQU12## IDFT in the subsampled DFT channelizer of FIG. 4 are {r o [n],r L [n],r 2L [n], . . . ,r m-L [n]}, (i.e., every L-th output of IDFT block in FIG. 3).
Similarly, the final outputs of the subsampled DFT-channelizer in FIG. 4 are {c o [n],c L [n],c 2L [n], . . . ,c m-L [n]}, (i.e., every L-th final output of the DFT-channelizer in FIG. 3).
For example, let us consider an analog signal x(n) of approximately 10 MHz of bandwidth, and let us assume that each radio channel conforms to the D-AMPS standard. Specifically, the channel spacing is f cs =30 KHz. Furthermore, let us assume that a 7/21 frequency reuse pattern is used. Hence, only every 7th channel needs to be extracted from x(n), i.e. L=7.
The full DFT-channelizer of FIG. 3 can be used to extract every 30 KHz band in x(n) if the sampling frequency of A/D converter is set at F s =34.02 MHz. In this case the total number of channels is ##EQU13## An IDFT of size 1134 needs to be implemented by the DFT-channelizer every ##EQU14## seconds. Since 1134 is a highly composite number, a Dooley-Tukey FFT algorithm can be used to compute this IDFT efficiently.
Alternatively, the subsampled DFT -channelizer of FIG. 4 can be used to extract only every 7th channel from x(n) (i.e., L=7 if the sampling frequency of the A/D converter is set at F s =34.02 MHz. In this case, a 162-point IDFT needs to be implemented by the subsampled DFT-channelizer every ##EQU15## (since M/L=1134/7=162). The complexity of a 1134-point IDFT is about 7 times the complexity of a 162 point IDFT.
Referring now back to FIG. 4, the discrete wideband signal x[n] is sampled and filtered by the bank of polyphase filters 100 to generate the sequence s i [n]. Each branch of the s i [n] signal is time aliased by L at 105 to generate a new sequence z i [n]. ##EQU16## IDFT 110 is taken of the sequence z i [n] to yield the sequence r i [n]. This sequence is mixed with carrier signal sequence e jWrNn . ; where ##EQU17## at mixer 115 to yield the selected channels from the wideband signal.
The ##EQU18## IDFT in the subsampled DFT-channelizer can be computed using any known fast algorithm for computing DFT/IDFT. These algorithms include the radix-2 FFT algorithm, the Cooley-Tukey FFT algorithm, the Wionogard prime-length FFT algorithm, and the prime-factor FFT algorithm. Depending on the exact value of M/L, a particular algorithm for computation of the IDFT might be more efficient. Hence, the free parameters of the subsampled DFT-channelizer (e.g., F s and M) can be chosen such that the resulting IDFT can be computed more efficiently using a particular FFT/IFFT algorithm. In other words, these parameters can be chosen to get an IDFT size that can be computed efficiently.
For example, if M/L is a highly composite number, the Cooley-Tukey FFT algorithm can be used to efficiently compute the resulting IDFT. On the other hand, if M/L is a prime number, the Winograd prime-length FFT algorithm can be used to efficiently compute the resulting IDFT. Finally, if M/L is a power of four, the radix-4 FFT algorithm can be used to efficiently compute the resulting IDFT.
Although a preferred embodiment of the method and apparatus of the present invention has been illustrated in the accompanying Drawings and described in the foregoing Detailed Description, it is understood that the invention is not limited to the embodiment disclosed, but is capable of numerous rearrangements, modifications, and substitutions without departing from the spirit of the invention as set forth and defined by the following claims. | A receiver and channelizer for processing a wideband signal is disclosed. The channelizer consists of a receiver for receiving a wideband signal. The received wideband signal is processed by a subsampled DFT-channelizer to extract a selected number of regularly spaced channels from a plurality of channels within the received wideband signal. These extracted regularly spaced channels are then output for further processing by a receiver. | 7 |
CROSS-REFERENCE TO RELATED APPLICATION
This application is a divisional of U.S. application Ser. No. 11/105,801 filed on Apr. 14, 2005.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates generally to the field of puzzles, and more particularly to the manufacture of customized jigsaw puzzles.
2. Description of Related Art
Public photographic vending machines are well known in the prior art. These machines typically include cameras which can take photographs of individuals sitting in the machine or booth. These photographs are developed by the machine and dispensed to the individual. More modern photographic vending machines include systems that are able to produce a photographic montage using an image of the user in combination with a stored image selected by the user.
There is consumer interest in personalized jigsaw puzzles which include an image or a modified image chosen by the consumer. For example, French patent application FR 2,653,350 (published Apr. 26, 1991) describes a process for creating a jigsaw puzzle from a photograph. The photograph is glued to a cardboard sheet, and then the photograph and the cardboard sheet are pressed together and then are cut into pieces to form a jigsaw puzzle. Unfortunately, the production of individual cardboard jigsaw puzzles is generally not economically feasible, primarily due to equipment costs, as such puzzles are mass-produced and cut using giant industrial presses. A flourishing business still exists for hand-cut personal and custom puzzles, as is evidenced by various web sites that offer this service. These mainly use photographs glued to plywood that is then cut with either scroll saws or water jets.
WO 98/42420 (Japanese published Oct. 1, 1998) describes a jigsaw puzzle constructing vending machine. The machine captures a picture of an individual and permits the picture to be combined with a selected background. It may be overlaid with text, and morphing and retouching are suggested. The modified picture is then printed onto cardboard. The central portion of the cardboard is then cut out, leaving a surrounding cardboard frame, and the central portion is cut into puzzle pieces having curved but non-interlocking borders. The puzzle pieces are then dispensed. The surrounding cardboard frame is mounted on a backing and is dispensed separately, so that the cardboard pieces may be assembled within the frame by a child. Examples of materials to be used for the jigsaw puzzle sheet are listed and include paper (cardboard), wood (stain sheets), synthetic resins (soft and hard material), synthetic material, stone materials, woven fabrics, non-woven fabrics, cork, metals, leather and glass.
SUMMARY OF THE INVENTION
In at least one of the described embodiments, the invention relates to a method and apparatus for producing a customized jigsaw puzzle. The apparatus comprises an image capturing mechanism, such as a camera, that captures one or more images of one or more individuals, animals, or objects or combinations of these posed against a background. A computer that is linked to the mechanism and to a printer is programmed to print an image on flexible sheets having a printable surface. Then a press, having a platen carrying a jigsaw puzzle cutting die, when activated uses pressure to laminate together the flexible sheet bearing the printed image and a foam sheet thicker and more rigid than he flexible sheet, setting pressure responsive adhesive material used as a binder to form a laminated product, and substantially simultaneously to cut the laminated product into jigsaw puzzle pieces. Additionally, the apparatus may be provided for producing a custom puzzle using selecting means for selecting a first digital image containing at least two layers of images, within a bank of digital images and digital image capturing means for capturing a second digital image of subject individuals, animals, or objects. Further image processing means provide for integrating the second digital image between the at least two layers of the first digital image to obtain a composite image and puzzle production means for producing the custom puzzle with the digital composite image.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a plan view of a site showing a jigsaw puzzle machine designed in accordance with an embodiment of the invention in relation to a person or other subject that is to be photographed.
FIG. 2 shows a schematic view of a screen shot of a computer screen, according to an embodiment of the invention, illustrating the selection of a background scene for use in the design of a jigsaw puzzle.
FIG. 3 presents a perspective view of a child being photographed in front of a blue background, according to an embodiment of the invention.
FIG. 4 shows a schematic view of a screen shot of a computer screen, in accordance with an embodiment of the invention, illustrating the construction of a composite image having three layers.
FIG. 5 is a schematic view of a layout of a hard copy printout, according to an embodiment of the invention, printed on flexible paper and including both a puzzle picture and also a smaller picture, a bar code, and licensing information that is to be attached to the box which will contain the puzzle.
FIG. 6 presents a perspective view of a first flexible sheet bearing a puzzle picture being placed upon the pre-glued surface of a second sheet made of foam, in accordance with an embodiment of the invention.
FIG. 7 is a perspective view of a jigsaw puzzle resulting after pressure is applied to set the adhesive and to force a puzzle die against the laminated sheets to cut them into puzzle pieces.
FIG. 8 is a perspective view of custom packaging prepared in accordance with an embodiment of the invention.
FIG. 9 is a perspective view of a part of a jigsaw puzzle machine designed according to an alternate embodiment of the invention different from that shown in FIG. 1 .
FIG. 10 shows a flow chart illustrating the steps of a method for producing a custom jigsaw puzzle in accordance with one embodiment of the invention.
FIG. 11 shows a flow chart illustrating the steps of a method for producing a custom jigsaw puzzle, in accordance with another embodiment of the invention.
FIG. 12 shows a flow chart illustrating the steps of a method for producing a custom made package in accordance with another aspect of the invention.
FIG. 13 presents a schematic flow diagram of the entire process of producing customized puzzles, with many elements represented by block diagrams.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Referring to FIGS. 1 , 2 , 3 , 4 , 6 , 7 , and 13 , a jigsaw puzzle machine 20 ( FIG. 13 ) is disclosed. The jigsaw puzzle machine 20 can produce a custom jigsaw puzzle 30 ( FIG. 7 ) for a user from a composite image 22 ( FIGS. 4 and 13 ) that is a combination of an image of a subject person 24 (FIGS. 1 and 3 —the subject may also be a pet or a toy or some other object) with at least one stored image 34 ( FIG. 2 ), the composite image 22 being shown in FIG. 4 .
More particularly, the present invention is embodied in a jigsaw puzzle machine 20 which includes a programmed computer 43 that permits one to select a first digital stored image 34 containing at least two layers of images 36 , including background scenes 23 and foreground objects 25 (as shown in FIGS. 2 and 13 ), within a bank of digital images 38 . The machine 20 further includes digital image capturing means 40 (such as a camera or scanner or data port) for capturing a second digital image 42 of a person or other subject 24 . The machine 20 also includes image processing means 44 implemented using a computer 43 programmed with a layered image creation and printing program 41 for integrating the second digital image 42 between the at least two layers 36 of the first digital stored image 34 to obtain a composite image 22 (as shown in FIG. 4 ). The machine 20 also includes puzzle production means 46 ( FIG. 1 ) for producing the custom jigsaw puzzle 30 bearing the digital composite image 22 . Included in the puzzle production means 46 , and with reference to FIG. 13 , are a printer 53 which prints the composite image 22 onto a flexible sheet 48 , a puzzle cutting die 80 resting on a surface 78 , and either a platen 78 or a roller 82 arranged to apply pressure to laminate the printed flexible sheet 48 on to a foam backing sheet 50 that is pre-coated with adhesive 59 and to cut the laminated sheets into a jigsaw puzzle. The puzzle production means 46 also includes a stack of the foam sheets 51 and a supply of the flexible sheets 55 that feeds the printer 53 , as is shown in FIG. 13 .
A programmed computer 43 and a program 41 to assist one in selecting a first digital stored image 34 within a bank of digital images 38 cooperate with digital image capturing means 40 (such as a camera or photograph scanner or computer port for receiving digital image data from a camera or portable storage device or camera) which captures a second digital image 42 of a person or other subject 24 . Image processing means 44 in the form of a layered image creation and printing program 41 (such as Adobe's® Photoshop®) enable an operator to integrate the second digital image 42 into the first digital stored image 34 to produce a composite image 22 that may be printed on a flexible sheet 48 . Jigsaw puzzle production means 46 (see FIGS. 1 and 13 ) including the printer 53 and an apparatus for producing pressure (either platens 76 and 78 or the platen 78 and a roller 82 shown in FIG. 13 ) that laminates the sheet 48 onto a sheet 50 made of foam and that causes a puzzle die 80 to cut the laminated sheets 48 and 50 into puzzle pieces to produce the puzzle 30 ( FIG. 7 ).
The first sheet 48 , when pressure is applied, becomes attached to an adhesive coated 59 surface of the second sheet 50 which is made of foam (as is shown in FIG. 6 ). The foam sheets are pre-coated with the adhesive and are heated to set the adhesive, since the adhesive is thermally activated. The pre-coated sheets of foam are then stacked at 51 for convenient storage before use.
The image processing means 44 may include a memory 45 in which are stored pre-established parameters upon which the integrating of the images is based. It also includes a computer 43 provided with a keyboard and mouse 57 and a display 49 and programs 41 that can display the layered images and permit the operator to manipulate the composite image 22 and its layered elements 36 and 42 .
Referring to FIG. 9 , the jigsaw puzzle machine 20 in one embodiment (different from that shown in FIG. 1 ) may have an external housing 52 that covers the jigsaw puzzle production means 46 , the external housing 52 including movable parts 54 (to entertain any children) and an exit 56 . The jigsaw puzzle machine may also include a motor for moving the movable parts 54 , a sound generator for generating interesting machine sounds, a conveyer that conveys the finished custom jigsaw puzzle 30 from inside of the housing 52 to the waiting child or adult through the exit 56 , and a button 58 for activating the motor, the sound generator and the conveyer from outside of the housing 52 . In an embodiment of the invention, the housing 52 is modular and takes only 3 hours to assemble. A child goes to the housing 52 and presses a button 58 that triggers the production process during which some parts 54 at the base of the housing 52 move about while making machine sounds. In an embodiment of the invention, a small door 64 opens on one side of the jigsaw puzzle production means 46 , and a sound can be heard as packaging containing the custom jigsaw puzzle 30 is dropped through the opening 56 . The whole jigsaw puzzle production process can be accomplished within a relatively short period of time, in the order of minutes.
Referring to FIG. 6 , the foam sheet 50 may be made of a polyethylene foam having a thickness of at least 3 mm (non-toxic polyethylene foam or foam for a Perfalock™ System). The foam may be LD60, weighing 2.5 pounds per square meter when the sheets are 3 millimeters thick. The puzzle is cut out of an 11 inch by 17 inch sheets. In the case of the thin, flexible sheets 48 , the grain is parallel to the long dimension, and this is why the sheets are 11 by 17, rather than 17 by 11. This paper has a semi-gloss finish, suitable for ink jet color printing. During the puzzle manufacturing process, these sheets are cut down to 14 by 11 for adult puzzles, which can have 200 to 300 pieces. The 3 inch portion of the sheet not cut up into puzzle pieces can be used for generating box labelling, as will be explained. In the case of children's puzzles, the puzzles may be cut to considerably smaller sizes and the puzzle pieces may be cut larger, so that only 30 pieces are cut out. Different puzzle dies are provided which give these different results. The pre-glued surface 59 may be provided with a glue of a type which remains flexible after setting, thereby permitting the puzzles to bend without pieces falling out. The adhesive is preferably pressure sensitive hot melt adhesive.
Referring now to FIGS. 4 , 5 , 6 , the printing means can be a printer 53 that prints at least one additional, reduced size, copy 60 of the composite image 22 onto the first sheet 48 for use as a customized box label.
In one embodiment, and referring now to FIGS. 1 , 2 , and 3 , the digital image capturing means 40 comprises a digital camera arranged to capture the second digital image 42 of the person or other subject 24 in front of a uniformly coloured screen 62 . A child or person can select the specific image in which the child or person wants to be positioned, as if the child or person or pet or other object (a teddy bear, for example) is part of a scene with a cartoon character or in a movie scene or in any other scenery or image, using a multi-layer digital compositing technique. The machine 20 may include the selecting means 32 that aids the customer in selecting from storage the first digital image 34 which normally contains foreground objects 25 and background scenes 23 and also the image processing means 44 which combines a selected background scene 23 and a foreground object 25 with the second digital image 42 of a person or other object 24 , these means being implemented by the programmed computer 43 shown in FIG. 1 as a “Laptop” and also shown in FIG. 13 . The display 49 and keyboard and mouse 57 of the computer 43 may be used to grant user approval of the generated composite image 22 for use in designing the custom jigsaw puzzle 30 .
The person or other subject 24 may be placed in front of a uniformly coloured screen 62 (usually blue or green) with a defined pre-positioning of the person or other subject 24 so that the subject person 24 seems to interact with the stored image 34 or forms an integral part of the stored image 34 . In an embodiment of the invention, a child or a person is photographed in a pre-selected position matching a situation in the stored image 34 . A preset process allows a quick and effective photo shoot on the blue screen background 62 . Every scene has its own very simple process for capture of the photo. The photo will be taken in a store or shopping mall location or in any other location with public traffic.
In an embodiment of the invention, the selecting means 32 and the image processing means 44 that generate the composite image 22 are implemented by means of a programmed computer 43 (see FIG. 13 ) which generates the composite image 22 , typically a 3-layered digital composite image 22 . The computer 43 uses computer programs 41 , such as Photoshop™, AdvantEdge™, any other similar program, to sandwich the image 42 of the person or other object 24 in between the components (typically a background scene 23 and one or more foreground objects 25 ) or layers of the stored image 34 (the first image) to form the layered composite image 22 which is printed on one of the flexible sheets 55 that forms the upper surface 59 of the custom puzzle 30 .
In an embodiment of the invention, a photographer/technician transfers the composite image 22 from the computer 43 to a high resolution printer 53 located within the jigsaw puzzle production means 46 . The high resolution printer 53 or a colour photocopier produces a print containing different sections (shown in FIG. 5 ). These include one bigger size image 22 for use as the face of the puzzle. Also included is a smaller image of the child in the puzzle setting for use as a label for the puzzle box. Additional box label information may be printed out. Thus, if the background scene 23 or any foreground objects 25 are licensed images, the copyright notice and the terms of the license may need to be printed out on the puzzle box. Ant to facilitate the gathering of accounting information to track royalty payments, a UPC bar code 74 may have to be printed out and studied. Note that all image sizes and die-cut jigsaw puzzle sizes are subject to vary and change, depending on the die line of the jigsaw puzzle.
In one embodiment of the invention, the jigsaw puzzle production means 46 provides means for transferring the larger hardcopy version of the composite image 22 and pre-glued foam sheet 50 (shown in FIG. 6 ) to a press or roller machine. The press's platens 78 and 76 ( FIG. 12 ) may squeeze the puzzle die against the foam sheet 50 and the printed image sheet 48 . The puzzle die has a Masonite™ base one-half inch thick into which puzzle grooves are cut, and then metal strips are pushed in to the grooves to do the cutting. A hard rubber pad is then squeezed into the die and cut so that it fills the spaces between the metal strips and enables great force to be applied to the laminated layers. As an alternative to a press, and requiring considerably less force to develop high pressure, a roller 82 may be mounted over the lower platen 78 and die 80 . In one arrangement, the platen 78 is mounted on rollers and rolls under the roller 82 which compresses the two sheets together in a manner similar to an old fashioned clothes ringer. Since pressure is applied along a thin line, rather than over a large area all at once, considerably less downward force is needed when the roller 82 is used than when two platens 76 and 78 and a press (not shown) are used.
In one embodiment of the invention, the jigsaw puzzle production means 46 also includes means for affixing on generic packaging for each custom jigsaw puzzle one of the at least one smaller hardcopy version 60 of the composite image 22 on a predetermined location on the packaging, as well as means for inserting the fully die cut jigsaw puzzle pieces into the packaging and means for closing the packaging containing the custom jigsaw puzzle. The technician affixes on generic packaging for each personalized jigsaw puzzle a small copy 60 of the composite image 22 on a predetermined location on the packaging. Other smaller images can also be generated as backups for the packaging, or alternately they may be inserted into the box to serve as a colour reference to facilitate jigsaw puzzle assembly. Any legal information 72 , including licence information and copyright notices, any logos and trade-marks 72 related to the use of licensed images in the jigsaw puzzle can also be affixed on a predetermined location on the packaging, as well as a UPC code 74 related to the custom jigsaw puzzle. The technician then inserts the fully die cut jigsaw puzzle pieces into the package which is closed and ready to come out of the jigsaw puzzle production means 46 to be taken home. And as noted above, the bar code allows full automation of the count of each puzzle sold to serve as a basis for royalty payments.
According to the invention, as shown in FIG. 10 , there is provided a method for producing a custom jigsaw puzzle, comprising steps of:
a) selecting 102 a first digital stored image containing at least two layers of images, within a bank of digital images; b) capturing 104 a second digital image of a person or other subject; c) integrating 106 the second digital image between the at least two layers of the first digital stored image to obtain a composite image 22 ; and d) producing 108 the custom jigsaw puzzle with the digital composite image 22 .
Step d) can include the steps of:
printing a first copy of the composite image 22 onto a first sheet; securing the first sheet onto a pre-glued surface 59 of a second sheet made of foam, to obtain a double sheeted member; and die cutting the double sheeted member to obtain the custom jigsaw puzzle.
Step c) can include the step of storing pre-established parameters upon which the integrating is based.
Step c) can further include the steps of displaying the composite image 22 on the display 49 and manipulating the composite image 22 .
In step d), the second sheet can be made of a polyethylene foam having a thickness of at least 3 mm.
In step d), the pre-glued surface 59 may be provided with a glue of a type which remains flexible after setting thereof.
In step d), the glue may be pressure sensitive hot melt adhesive.
Step d) can include the step of printing at least one additional copy 60 of the composite image 22 onto the first sheet, the at least one additional copy 60 being smaller than the first copy 22 .
In step b), the person or other subject 24 may be positioned in a predetermined position in the second digital image 42 to match a situation determined by the at least two layers of the first digital stored image 34 .
Step b) involves capturing a third digital image of another person or other subject, and step c) involves integrating the third digital image between the at least two layers of the first digital stored image within the composite image 22 .
According to the invention, as shown in FIG. 11 , there is also provided a method for producing a custom jigsaw puzzle, comprising steps of:
a) selecting 112 a first digital stored image, within a bank of digital images; b) capturing 114 a second digital image of a person or other subject; c) integrating 116 the second digital image into the first digital stored image to obtain a composite image 22 ; and d) producing 118 the custom jigsaw puzzle on a sheet made of foam with the composite image 22 .
Step d) comprises the steps of:
printing a first copy of the composite image 22 onto a first sheet; securing the first sheet onto a pre-glued surface 59 of a second sheet made of foam, to obtain a double sheeted member; and die cutting the double sheeted member to obtain the custom jigsaw puzzle.
Step c) may include storing pre-established parameters upon which the integrating is based.
Step c) can involve displaying the composite image 22 on the display 49 and using the keyboard and mouse 57 to manipulate the composite image 22 .
In step d), the second sheet is preferably made of a polyethylene foam having a thickness of at least 3 mm., but it may be as thick as ¼ inch or more, particularly for children's puzzles.
In step d), the pre-glued surface 59 is preferably provided with a glue of a type which remains flexible after setting thereof.
In step d), the glue is a pressure sensitive hot melt adhesive.
The step d) can include printing at least one additional copy 60 of the composite image 22 onto the first sheet, the at least one additional copy 60 being smaller than the first copy 22 .
In step b), the person or other subject 24 may be placed into a predetermined position in the second digital image 42 to match a situation or scene established by the first digital stored image 34 .
Step b) may involve capturing a third digital image of another person or other subject 24 , and step c) may then involve integrating this third digital image in with the first two digital images 34 and 42 within the composite image 22 .
The production of a custom jigsaw puzzle 30 for a user from a composite image 22 montage combining an image of a person or other subject with at least one stored image (from a variety of stored images offered to a user) may be carried out using the following more detailed sequence of steps:
a) selecting, from a variety of stored images offered to a user, at least one stored image in which the person or other subject is to be positioned;
b) taking a photographic image of the person or other subject in front of a blue screen with a defined pre-positioning of the person or other subject so that such subject person seems to interact with the stored image or forms an integral part of the stored image;
c) generating the image montage including the photographic image of the person or other subject positioned within the at least one stored image;
d) approving the generated image montage for use on the jigsaw puzzle;
e) transferring the image montage to the jigsaw puzzle production means;
f) triggering a start of the production of the jigsaw puzzle;
g) initiating movement of movable parts 54 of external housing of the jigsaw puzzle production unit during production of the jigsaw puzzle;
h) producing at least one larger hardcopy version of the image montage and at least one smaller hardcopy version of the same image montage;
i) applying the larger hardcopy version of the image montage to a pre-glued foam sheet;
j) transferring the larger hardcopy version of the image montage and pre-glued foam sheet to pressing means;
k) gluing the larger hardcopy version of the image montage to the pre-glued foam sheet;
l) die cutting the glued image montage and foam sheet received from the pressing means into jigsaw puzzle pieces;
m) affixing on generic packaging for each custom jigsaw puzzle one of the smaller hardcopy versions of the image montage on a predetermined location on the packaging, as well as a custom UPC code and any appropriate legal data;
n) inserting the fully die cut jigsaw puzzle pieces into the packaging;
o) closing the packaging; and
p) providing the custom jigsaw puzzle to the user through an opening in the jigsaw puzzle production unit.
Referring now to FIG. 8 , another aspect of the custom made packaging 70 is the need to provide a memory, such as the memory 45 of the computer 43 shown in FIG. 12 for storing data. Programming is needed that can select the correct legal data 72 from a first bank of data stored in the memory 45 , in relation to a specific product, and also select the proper UPC bar code 74 from those stored within a second bank of data stored in the memory 45 . This ties in with the means for selecting visual data 60 which determines which royalty information is applicable and which bar code corresponds to the selected background scene and foreground objects, and a reduced size version of the visual data is included on the label. Thus, a third bank of data stored in the memory 45 is needed. And of course means are required for applying the legal data 72 , the UPC bar code 74 and the visual data 60 onto a generic package to produce the custom made packaging 70 .
The means for selecting can be the computer 43 provided with a display 49 and with a keyboard and mouse 57 , as is shown in FIG. 13 .
The first bank of data is data chosen within the group including license data, copyright data, logo data and trademark data.
The third bank of data includes the composite images 22 including a person or other subject 24 .
The applying means may include the printer 53 which prints the legal data 72 , the UPC bar code 74 and the visual data 60 on stickers that can be applied on the generic packaging. As illustrated in FIG. 5 , these may be printed on a portion of the same first flexible sheet 48 on which the puzzle's composite image 22 is printed and cut off to form labels by the puzzle cutting die 80 , as is illustrated schematically in FIG. 13 .
In one embodiment of the invention, the apparatus for producing a custom made packaging can be used in conjunction with the jigsaw puzzle machine described above, in order to produce a custom made packaging wherein the visual data 60 on the packaging corresponds to the composite image 22 shown on the custom jigsaw puzzle. The legal data in this case will be any legal information (copyright, licenses, logo, trade-mark or others) related to licensed images used in the composite image 22 . The UPC code is related to the type of custom jigsaw puzzle produced and to the imagery used in the composite image 22 , to ensure proper tracking of inventory and sales of products.
Referring now to FIG. 12 a method for producing the custom made packaging is described in that figure and below, involving a number of basic steps to which may a plurality of optional steps may be added, as is explained below. According to the invention, there is provided a method for producing a custom made packaging, comprising steps of:
a) selecting 122 legal data within a first bank of data stored in a memory, in relation to a product; b) selecting 124 a UPC bar code within a second bank of data stored in the memory, in relation to the product; c) selecting 126 visual data 60 within a third bank of data stored in the memory, in relation to the product; and d) applying 128 the legal data, the UPC bar code and the visual data 60 on a packaging to obtain the custom made packaging.
The steps a), b) and c) are performed by means of the computer 43 which is provided with a display 49 and with a keyboard and a mouse 57 .
In step a), the first bank of data can be data chosen within the group including license data, copyright data, logo data and trademark data.
In step c), the third bank of data is the composite image 22 including a person or other subject.
The step d) includes printing the legal data 72 , the UPC bar code 74 , and the visual data 60 on stickers to be applied on the generic packaging. Alternatively, this step can include printing the legal data 72 , the UPC bar code 74 and the visual data 60 on the generic packaging.
Although just a few embodiments of the invention have been described, it should be understood that the invention is not limited to these precise embodiments, and that various changes and modifications may be made without departing from the scope or spirit of the invention as set forth in the claims annexed to and forming a part of this specification. | A method and apparatus for producing a customized jigsaw puzzle is disclosed. The apparatus comprises an image capturing mechanism, such as a camera, that captures one or more images of one or more individuals, animals, or objects or combinations of these posed against a background. A computer that is linked to the mechanism and to a printer is programmed to print an image on flexible sheets having a printable surface. Then a press, having a platen carrying a jigsaw puzzle cutting die, when activated uses pressure to laminate together the flexible sheet bearing the printed image and a foam sheet thicker and more rigid than he flexible sheets, setting pressure responsive adhesive material used as a binder to form a laminated product, and substantially simultaneously to cut the laminated product into jigsaw puzzle pieces. | 8 |
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The invention relates generally to access control in a communication system and, more particularly, to a method and system for blocking access to specific wide area network addresses in a communication system.
[0003] 2. State of the Art
[0004] Conventional telephony services are generally provided over circuit-switch networks commonly known as Public Switched Telephone Networks (PSTN). For calls originating over the PSTN, a connection is formed between the calling party and the called party that is exclusive to all other users. When the established call is completed, the connection is opened and the corresponding lines are available for the establishment of a subsequent call through a connection and reuse of one or more lines.
[0005] Currently, there is a growing migration from communications which are based over the PSTN toward communication which are based over a connectionless network such as the Internet wide area network. Such communication over the Internet is commonly known as Internet telephony and is further commonly known as Voice-over-IP (VoIP). Internet telephony is a service provided over an IP network such as a packet switched network. Internet telephony recognizes efficiencies in transmitting packets carrying data for communication between a called and a calling party over a network without reserving or dedicating specific connections between the parties for the duration of the call. Such an approach digitizes audio signals and packetizes them into packets for transmission across the IP-based network. On the receiving end, the packets are depacketized and the data is transformed into audio for playback for the receiving party.
[0006] Since the data is carried digitally across the IP network, other information such as video data may be incorporated into Internet telephony without substantial modifications. Due to the ease of integrating audio and video data into Internet telephony, video phones are becoming more ubiquitous. Additionally, services, an example of which are interpretive sign language services for the hearing impaired, are also made available through the utilization of video phones by making the transmission of video imaged sign language expressions transmittable over an Internet telephony system.
[0007] Accordingly, significant capital investments into the development and manufacturing of improved video telephony devices has become more commonplace. As investment in equipment development and services increases, equipment manufacturers and service providers have an economical interest in encouraging selection of their equipment and services by a consumer. It is not uncommon in commercial applications for service providers to make available to customers equipment at a competitive or even subsidized rate for utilizing their services. Therefore, there is motivation for Internet telephony equipment providers to safeguard their equipment from being utilized by services that are not associated with an equipment provider. While such a motivation is specific, more general motivations exist for preventing or blocking access by an Internet device such as a videophone to undesirable, rogue or competitive services or locations on the network.
BRIEF SUMMARY OF THE INVENTION
[0008] A method and system for blocking network resources is provided. In one embodiment of the present invention, a method for blocking access to specific network resources is provided. The method receives a request for a connection to a specific network resource as identified by a specific identifier. The specific identifier is compared against entries in a stored blacklist while the blacklist includes blocked network resource identifiers. When the specific identifier matches one of the entries within the blacklist, the connection to the specific network resource is denied and when the specific identifier does not match one of the entries within the blacklist, the connection to the specific network resources is allowed.
[0009] In another embodiment of the present invention, a network device is provided. The network device includes a first portion of storage configured to retain a list of entries in a stored blacklist with the blacklist including blocked network resource identifiers. The network device further includes a control process configured to receive and compare a request for a connection to a specific network resource as identified by a specific identifier. The comparison is made with the list of entries in the stored blacklist which include the blocked network resource identifiers. The control process is further configured to deny the connection to the specific network resource when the specific identifier matches one of the entries within the blacklist. The control process is further configured to allow the connection to the specific network resource when the specific identifier does not match one of the entries within the blacklist.
[0010] In a further embodiment of the present invention, a system for selectively blocking access to specific network services is provided. The system includes a network device which further includes storage configured to store entries in a stored blacklist which includes blocked network resource identifiers. The network device further includes a control process configured to receive and compare a request for a connection to a specific network resource as identified by a specific identifier. The comparison is made against the list of entries in the stored blacklist including blocked network resource identifiers. The control process is further configured to deny the connection to the specific network resource when the specific identifier matches one of the entries within the blacklist and to allow the connection to the specific network resource when the specific identifier does not match one of the entries within the blacklist. The system further includes an associated service preferably selected by the network device which is identified by a stored service number located within the network device which identifies the associated service. The system additionally includes a network for selectively addressably coupling the network device with the associated service.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS
[0011] In the drawings, which illustrate what is currently considered to be the best mode for carrying out the invention:
[0012] FIG. 1 illustrates an IP-based communication system incorporating an exemplary service, in accordance with an embodiment of the present invention;
[0013] FIG. 2 illustrates a simplified block diagram of a communication system configured for interacting with a video phone, in accordance with an embodiment of the present invention;
[0014] FIG. 3 is a block diagram illustrating details of an access control or blacklist, in accordance with an embodiment of the present invention;
[0015] FIG. 4 is a flow diagram of a power up sequence of an IP device, in accordance with an embodiment of the present invention;
[0016] FIG. 5 is a flow diagram of a blacklist update process of an IP device, in accordance with an embodiment of the present invention; and
[0017] FIG. 6 is a flow diagram of an IP device call initiation process configured to block access to specific network entities, in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0018] Generally, IP devices may access essentially all IP addressable network elements. However, for various reasons, there are certain applications where access to specific resources identified by an IP address would be preferably denied. By way of example, and not limitation, one exemplary IP device may be a video phone which may be deployed to a user at a full, subsidized or reduced fee in conjunction with offered services. In such an example, it would be inherently disadvantageous to allow a user to circumvent utilization of an associated service coupled to a deployed IP device when such an agreement or understanding to the contrary exists. Additionally, it may also be advantageous for the protection of users of IP devices to be protected from unethical or immoral resources identified by one or more specific IP addresses. Therefore, the various embodiments of the present invention utilize a list of current IP addresses and/or domain names uniquely identifying a particular network resource causing the IP device to be incapable of connecting or interacting with the identified or blacklisted resource or device.
[0019] By way of example, and not limitation, various embodiments of the present invention are disclosed in conjunction with a specific network resource identified herein as a video service, more specifically, the exemplary video service may be configured as a translation video service for assisting in communication with the hearing impaired. While such a specific service is illustrative, it is by no means to be interpreted as limiting of the scope of the present invention. Furthermore, the use of the terms “service” and “network resource” are not to be considered as limiting of specific services but rather also includes any network addressable device, resource, web page, or other entity uniquely selectable by an IP address or domain name or other network addressing mechanism.
[0020] FIG. 1 illustrates an IP-based communication system, in accordance with an embodiment of the present invention. As stated, the present example includes an exemplary IP-based service depicted as a translation service for the hearing impaired while the scope of the present invention is not so limiting. The use of such a specific example is for illustrative purposes and is not to be construed as being limiting of the invention which finds broader application to all IP services. A communication system 10 enables a user 14 (e.g. a hearing impaired user) to engage in conversation through a communication system with a user 11 through the use of IP devices 12 , 13 . The communication system 10 may also enable a user 14 to engage in conversation through a communication system with a user 16 via a specific network service such as an associated service 20 . A communication session between the users is facilitated through the use of various equipments, which are preferably coupled together using various networks.
[0021] To interface a user 14 with a user 11 , a network 17 accommodates the coupling of an IP device 12 with a different IP device 13 . In the specific service application as described herein, a hearing impaired user may be interfaced with a generally voice-based communication system through associated services 20 (e.g., interpretive services) allowing the hearing impaired user to communicate with an interpreter, namely through engaging in the act of sign language. The sign language images are then translated by the associated service 20 and when translated into voice information, are then forwarded over a voice-based communication connection to a hearing-capable user 16 . One means for relaying the communicative expressions of a user 14 (e.g. a hearing impaired user) within communication system 10 incorporates an IP device 12 configured as a video phone for capturing the communicative expressions exhibited by user 14 (e.g. a hearing-impaired user) and for displaying as received, interpreted voice information originating from the user 16 (e.g. a hearing-capable user).
[0022] In the present exemplary illustration, expressions, such as sign language and/or body language, may be interpreted or translated by associated services 20 . Additionally, user 16 interacts in the conventional manner with the associated service 20 through the use of a voice-based dialogue conveyed over a conventional voice phone 22 . The various devices, such as IP device 12 and conventional voice phone 22 are coupled to the associated service 20 using one or more networks 17 , 18 . To facilitate the enhanced bandwidth needs of IP device 12 , network 17 may be implemented as a high bandwidth network such as a wide area network, an example of which is the Internet. The conduit for coupling an IP device with the network 17 may further include an Internet Service Provider (ISP), the details of which are not shown herein but are known by those of ordinary skill in the art. Network 18 may be implemented according to the standards and bandwidth requirements of a conventional voice phone 22 .
[0023] In accordance with one or more embodiments of the present invention, the IP device 12 may be configured to prevent access by user 14 to unauthorized or blacklisted services. In the communication system 10 , a blacklist database 502 is coupled to the IP device 12 through network 17 . Upon the occurrence of an event or other required condition, IP device 12 through network 17 accesses the blacklist database 502 to retrieve a blacklist 500 containing identifiers (e.g. IP addresses and/or domain names) of services or IP devices that are otherwise blocked from being accessed by the IP device 12 . As illustrated, the blacklist may include an IP address, domain name, or other identifier which uniquely addresses a specific network resource such as a blacklisted service 21 . On the retrieval of the blacklist 500 and evaluation of the stored blacklist 500 ′ within the IP device 12 , access to, for example, the blacklisted service 21 would be denied. In one example, the blacklisted service 21 may be a competitive service to the associated service 20 and the incorporation of the blacklist 500 ′ and the evaluation thereof by IP device 12 prior to the initiation of a service request or attempted connection with a blacklisted IP device would be prohibited. It should be noted that the blacklist 500 ′ may contain an identifier to a blacklisted service, or blacklisted IP device, an example of which may be IP device 13 which is determined to be a device to which IP device 12 is not authorized to interact with.
[0024] FIG. 2 is a simplified block diagram of a communication system configured for restricting access of an IP device to other IP devices or services, in accordance with an embodiment of the present invention. To facilitate interaction of a user with another user; an IP device 12 , configured herein as an exemplary, but not limiting, video phone, includes video components such as a camera 24 , for capturing the communicative expression of a user and further includes a display or monitor 26 for displaying the communicative expressions originating from the other user. The IP device 12 , in accordance with an embodiment of the present invention, may further include a keypad 28 or other data entry device configured to enable the user to initiate a communication session in a conventional manner by entering a telephone number of the called user which may include an IP address, and is stored in storage 19 and captured therein as a called party number 32 . The call from IP device 12 may be initiated through data entry similar to inputting a telephone number on a conventional telephone or through the input of an IP address through a graphical interface.
[0025] A control process 30 may initiate the retrieval or update of a blacklist 500 by retrieving a blacklist IP address 504 and initiating the retrieval of the blacklist 500 located within the blacklist database 502 through network 17 . Upon retrieval, IP device 12 stores a copy of the blacklist 500 as blacklist 500 ′ for comparison when initiating communication sessions as directed by a user. The specific flow processes related to the comparison of an input IP address or domain name with those stored within the blacklist 500 ′ will be further discussed below with reference to FIGS. 4-6 .
[0026] In the exemplary associated service described herein, the control process 30 retrieves a stored service number 34 which may be associated with a specific IP address 202 or domain name 201 . In another configuration, the IP address 202 or domain name 201 may identify a specific associated service which is looked-up using a protocol such as DNS or LDAP contacts a DNS or an LDAP server 200 and passes thereto a domain name or stored service number 34 and requests therefrom a corresponding IP address which is returned to IP device 12 . IP device 12 thereafter initiates a call, upon the successful comparison against blacklist 500 ′, to associated service 20 over network 17 using, for example, the corresponding IP address 202 or the IP address returned from the LDAP server 200 . Thereafter, control process 30 initiates a communication session over network 17 between IP device 12 and associated services 20 .
[0027] By further example, and not limitation, the communication session between IP device 12 and associated service 20 may be more specifically initially connected to a hold server 44 within an associated service 20 . Hold server 44 communicates with a VRS server 45 and when hold server 44 receives an inbound call in the form of a call request for the establishment of a communication session between IP device 12 and associated service 20 , hold server 44 notifies VRS server 45 of the intention to establish a communication session between IP device 12 and a conventional phone 22 . During the establishment of the communication session between IP device 12 and associated service 20 , IP device 12 passes a call request including calling information to hold server 44 . The call request is subsequently passed to VRS server 45 including the calling information which includes a video phone number 204 , a MAC address 206 , a name 208 and the captured call party number 32 . The VRS server 45 includes and maintains a cue for one or more calls originating from the IP device 12 seeking to establish or maintain a communication session utilizing, for example, interpretive services as provided within the VRS client 36 .
[0028] FIG. 3 is a block diagram of a blacklist and its contents, in accordance with an embodiment of the present invention. The blacklist 500 is updated and maintained in a blacklist database 502 ( FIG. 2 ) and includes one or more entries of specific identifiers configured to uniquely identify a specific network address. By way of example, and not limitation, blacklist 500 may include one or more IP addresses 510 which uniquely identify one or more network resources that have been previously identified as restricted access by the IP device 12 ( FIGS. 1-2 ) configured according to the various embodiments of the present invention. Additionally, blacklist 500 may further contain one or more domain names 512 which may be further mapped to a specific IP address identifying a unique network resource. Those of ordinary skill in the art appreciate that network resources may be recognizably identified by a specific domain name which resolves into a specific IP address identifying the ultimate addressed network resource. While it may appear that utilization of a single type of blacklist identifier, namely an IP address, may be adequate for identifying the network resource that is to become blacklisted, it is also appreciated that the various network resource entities may maintain a readily recognizable domain name while periodically changing the IP address corresponding with the domain name. Therefore, such a rogue service could periodically remove itself from the IP addresses of the blacklist by merely reassigning a new corresponding IP address to the domain name.
[0029] FIG. 4 is a flow diagram illustrating the sequencing of an IP device during power up process 600 , in accordance with an embodiment of the present invention. An IP device, an example of which is a video phone, receives power as applied thereto and in accordance with the present invention, retrieves 602 a blacklist 500 ( FIG. 2 ) over the network 17 ( FIG. 2 ) from a blacklist database 502 ( FIG. 2 ). The blacklist 500 ( FIG. 2 ) is retrieved utilizing the blacklist IP address 504 ( FIG. 2 ) stored within the IP device 12 during a configuration process. Upon receipt of the blacklist 500 , the IP device internally stores 604 the blacklist 500 as received from the blacklist database 502 as a copy of the blacklist 500 ′ for subsequent comparison during call initiation processes.
[0030] FIG. 5 is a flow diagram of an IP device blacklist update process 650 configured to maintain a current version or retrieve an updated version of the blacklist 500 ′, in accordance with an embodiment of the present invention. It is contemplated that the update process may be driven by one or more events including time based/periodic update events, call initiation events by the IP device, a notification process to the IP device of a newer available version of the blacklist (e.g., email or other notification mechanism) or other event mechanisms as known by those of ordinary skill in the art. The update process 650 queries 652 for the occurrence of an update event and upon the detection of such an event the IP device retrieves 654 the blacklist 500 as stored on a blacklist database 502 ( FIG. 2 ). The modification of the blacklist 500 within the blacklist database 502 ( FIG. 2 ) may include update mechanisms known by those of ordinary skill in the art including the use of intelligence gathering mechanisms such as through the use of web crawlers, heuristic methods as well as industry knowledge by those of ordinary skill in the art. Such updated mechanisms for keeping the blacklist 500 current within the blacklist database 502 is not further discussed herein. Upon retrieval of a current version of the blacklist 500 from the blacklist database 502 ( FIG. 2 ), the IP device internally stores 656 a copy of the blacklist 500 ′ within the IP device 12 ( FIG. 2 ).
[0031] FIG. 6 is a flow diagram of an IP device call initiation process 605 , in accordance with an embodiment of the present invention. Through user activation or otherwise, the IP device initiates a call request 606 which may include a specific identifier such as an entered IP address, domain name, or conventional phone number or name resolved into one of an IP address or domain name. The call initiation process determines 608 if the call was initiated using a domain name. If a domain name was utilized, the IP device compares 610 the domain name against the blacklist 500 ′ ( FIG. 2 ) to determine 612 if the domain name is located within the blacklist 500 ′. If the domain name utilized for initiating the call is located with the blacklist 500 ′, then the IP device denies 618 the completion of the call and may alternatively notify the user of such denial. If the domain name is not on the blacklist, then the IP device resolves 614 the domain name into an IP address for further comparison.
[0032] The IP device compares 616 the IP address against the blacklist 500 ′ if either call initiation did not utilize a domain name in the call request as determined in query 608 or if the IP device was resolved 614 from a domain name to an IP address. Therefore, either the call initiated IP address or the domain name resolved IP address is compared 616 to determine 620 if the IP address is located within the blacklist 500 ′. If the IP address is located within the blacklist 500 ′, then the IP device denies 618 completion of the call. However, if the IP address is not located within the blacklist 500 ′, then the IP device allows 622 completion of the call.
[0033] Although the foregoing description contains many specifics, these are not to be construed as limiting the scope of the present invention, but merely as providing certain exemplary embodiments. Similarly, other embodiments of the invention may be devised which do not depart from the spirit or scope of the present invention. The scope of the invention is, therefore, indicated and limited only by the appended claims and their legal equivalents, rather than by the foregoing description. All additions, deletions, and modifications to the invention, as disclosed herein, which fall within the meaning and scope of the claims are encompassed by the present invention. | A system and method for blocking access by a network device to specific network resources by comparing a specific resource identifier against entries in a blacklist and facilitating a connection accordingly. A request for a connection to a specific network resource identified by a specific identifier is received and compared against entries in a stored blacklist. When the specific identifier matches one of the entries within the blacklist, the connection to the specific network resource is denied and when the specific identifier does not match one of the entries within the blacklist, then the connection to the specific network resource is allowed. The system further includes a blacklist database that maintains an updated copy of the blacklist and the network device retrieves an updated version upon the occurrence of specific events. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser. No. 11/080,009, filed Mar. 14, 2005, entitled “Biologically Implantable Prosthesis And Methods Of Using The Same”, which is a continuation of co-pending application Ser. No. 10/327,821, filed Dec. 20, 2002, the entire teachings of which are incorporated herein by reference.
BACKGROUND
[0002] 1. Field of the Invention
[0003] The present invention relates generally to a biologically implantable prosthesis, a heart valve assembly using the prosthesis, and methods of using the same within an annulus of the body.
[0004] 2. Description of the Related Art
[0005] Prosthetic heart valves can replace defective human valves in patients. Prosthetic valves commonly include sewing rings or suture cuffs that are attached to and extend around the outer circumference of the prosthetic valve orifice.
[0006] In a typical prosthetic valve implantation procedure, the heart is incised and the defective valve is removed leaving a surrounding area of locally tougher tissue. Known heart valve replacement techniques include individually passing sutures through the tough tissue to form an array of sutures. Free ends of the sutures are extended out of the thoracic cavity and laid, spaced apart, on the patient's body. The free ends of the sutures are then individually threaded through an edge around the circumference of the sewing ring. Once all sutures have been run through the ring, all the sutures are pulled up taught and the prosthetic valve is slid or “parachuted” down into place adjacent the tough tissue. Thereafter, the prosthetic valve is secured in place by traditional knot tying with the sutures.
[0007] The sewing ring is often made of a biocompatible fabric through which a needle and suture can pass. The prosthetic valves are typically sutured to a biological mass or annulus that is left when the surgeon removes the existing valve from the patient's heart. The sutures are tied snugly, thereby securing the sewing ring to the annulus and, in turn, the prosthetic valve to the heart.
[0008] Sewing rings can be tedious to secure to the valve orifice. Further, attaching the sewing ring to the annulus can be time consuming and cumbersome. The complexity of suturing provides a greater opportunity for mistakes and requires a patient to be on cardiopulmonary bypass for a lengthy period. It is also desirable to provide as large of a lumen through the prosthetic valve as possible to improve hemodynamics. However, techniques for attaching the sewing ring to the orifice typically require the area of the valve lumen be reduced to accommodate an attachment mechanism. For example, the sewing ring is typically retained on top of the annulus, resulting in a lumen that is, at the largest, the size of the original lumen.
[0009] A patient can also have a natural valve lumen that is detrimentally small. In these cases, the natural valve can be gusseted before the prosthetic valve is implanted. To gusset the natural valve, a longitudinal incision can be made along the wall of the lumen. The lumen can then be circumferentially expanded and the now-expanded incision can be covered with a patch graft or other membrane and stitched closed.
[0010] U.S. Pat. No. 4,743,253 to Magladry discloses a suture ring with a continuous compression ring. Magladry's ring is ductile, but provides a compressive, not expansive, force. In fact, the ring taught by Magladry is intended for placement over a heart valve and provides compression on the heart valve.
[0011] U.S. Pat. No. 6,217,610 to Carpentier et al. discloses an expandable annuloplasty ring. Carpentier et al. teach expanding the ring over the life of a patient by increasing the size of the ring by balloon dilatation. The ring is intended to remodel the shape of the valve annulus, not serve as a foundation to attach a second prosthesis and form a heart valve.
[0012] U.S. Pat. No. 5,984,959 to Robertson et al. discloses an expandable heart valve ring for attaching a synthetic valve thereto and a tool for attaching the ring to the synthetic valve. Robertson et al. teach the ring as having tabs that are used to attach to the second prosthesis by using a second device to engage the tabs.
[0013] There is a need for a circumferentially expandable bio-prosthesis. There is also a need for a prosthesis and method that can expand an annulus and maintain an enlarged annulus circumference. Furthermore, there is a need for a minimally invasive heart valve replacement procedure. Also, there is a need for a prosthesis that can provide for the above and engagement with a second prosthesis, for example, the crown of a heart valve. Furthermore, there is a need for the above prosthesis that can self-engage a second prosthesis to improve implantation time.
SUMMARY
[0014] One embodiment of the disclosed prosthesis is a biologically implantable first prosthesis for a heart valve having a circumferentially expandable wall. The wall has a latitudinal cross-section perpendicular to the longitudinal axis, and a longitudinal cross-section parallel to the longitudinal axis. The prosthesis also has an engagement element configured to self-engage a second prosthesis.
[0015] The first prosthesis can also have a stop, where the stop prevents the wall from circumferentially decreasing. The first prosthesis can also have a fixturing device connector. The wall can also be corrugated. The wall can also have a turned lip on its leading edge. The first prosthesis can also be in an assembly where the first prosthesis can receive a second prosthesis, for example a crown.
[0016] Another embodiment of the prosthesis is a biologically implantable first prosthesis for a heart valve having a wall with a first edge and a second edge. The wall has a longitudinal axis at the center of the first prosthesis, and the first edge has an engagement element for engaging a second prosthesis. The engagement element is also turned toward the second edge.
[0017] The engagement element can be curved toward the second edge. The first edge can be the leading edge. The first prosthesis can also have a fixturing device connector that can be a port in the wall. The wall can also be corrugated. The first prosthesis can also be in an assembly with a second prosthesis connected to the engagement element. The second prosthesis can be a crown.
[0018] An embodiment of a method of implanting a heart valve in a valve annulus is attaching a first prosthesis to the valve annulus and attaching a second prosthesis to the first prosthesis. The first prosthesis has a circumferentially expandable wall. The wall has a longitudinal axis, and the wall has a latitudinal cross-section perpendicular to the longitudinal axis.
[0019] The first prosthesis can be a ring. The second prosthesis can be a crown. The wall of the first prosthesis can have a first terminal end and a second terminal end. Attaching the first prosthesis can include fixing the first prosthesis to a biological mass with a fixturing device. Attaching the first prosthesis can also include snap-fitting the second prosthesis to the first prosthesis.
[0020] Another embodiment of a method of implanting a heart valve in a valve annulus includes attaching a first prosthesis to the valve annulus and attaching a second prosthesis to the first prosthesis. The first prosthesis has a wall having a first edge and a second edge. The wall also has a longitudinal axis. The first edge comprises an engagement element, and the engagement element is turned toward the second edge.
[0021] The engagement element can be turned away from the longitudinal axis. The first prosthesis can be a ring. The second prosthesis can be a crown. Attaching the crown can include snap-fitting the crown to the first prosthesis.
[0022] An embodiment of a method of increasing and maintaining the size of a biological valve annulus includes placing a circumferentially expandable first prosthesis in the annulus. The method also includes circumferentially expanding the first prosthesis, and circumferentially locking the first prosthesis.
[0023] Circumferentially expanding the first prosthesis can include increasing the radius of the annulus from about 0.1 mm (0.004 in.) to more than about 2.0 mm (0.08 in.). The first prosthesis can also have an engagement element configured to receive a second prosthesis.
BRIEF DESCRIPTION OF THE DRAWINGS
[0024] FIG. 1 is a bottom view of an embodiment of the prosthesis.
[0025] FIG. 2 is a top perspective view of the embodiment of the prosthesis of FIG. 1 .
[0026] FIG. 3 is a bottom view of another embodiment of the prosthesis.
[0027] FIG. 4 is a top perspective view of the embodiment of the prosthesis of FIG. 3 .
[0028] FIG. 5 is a bottom view of another embodiment of the prosthesis.
[0029] FIG. 6 is a top perspective view of the embodiment of the prosthesis of FIG. 5 .
[0030] FIG. 7 is a bottom view of another embodiment of the prosthesis with cut-away views of the collars.
[0031] FIG. 8 is a top perspective view of the embodiment of the prosthesis of FIG. 7 with cut-away views of the collars.
[0032] FIG. 9 is a bottom view of another embodiment of the prosthesis with cut-away views of the collars.
[0033] FIG. 10 is a top perspective view of the embodiment of the prosthesis of FIG. 8 with cut-away views of the collars.
[0034] FIG. 11 is a top perspective view of another embodiment of the prosthesis with magnets.
[0035] FIG. 12 illustrates cross-section A-A of FIG. 11 .
[0036] FIG. 13 is a top perspective view of another embodiment of the prosthesis with magnets.
[0037] FIG. 14 illustrates cross-section B-B of FIG. 13 .
[0038] FIG. 15 is a top perspective view of another embodiment of the prosthesis with magnets.
[0039] FIGS. 16-18 are top views of various deformable embodiments of the prosthesis in unexpanded states.
[0040] FIG. 19 is a top view of the embodiment of the prosthesis of FIG. 12 in an expanded state.
[0041] FIGS. 20-22 illustrate various embodiments of the fixturing device connectors.
[0042] FIGS. 23-25 illustrate various embodiments of the receiving elements.
[0043] FIGS. 26 and 27 are cut-away views of various embodiments of the receiving elements.
[0044] FIGS. 28-33 illustrate various embodiments of the protrusions.
[0045] FIG. 34 illustrates the steering elements.
[0046] FIGS. 35-43 are cross-sections of various embodiments of the wall of the prosthesis.
[0047] FIG. 44 illustrates an embodiment of the prosthesis of FIG. 38 .
[0048] FIGS. 45 and 46 illustrate cross-sections of the wall of the prosthesis with various embodiments of the covering.
[0049] FIGS. 47-52 illustrate various embodiments of the engagement element.
[0050] FIG. 53 is a cut-away view of an embodiment of positioning the prosthesis in an annulus with a solid view of the prosthesis.
[0051] FIG. 54 is a cut-away view of an embodiment of positioning the prosthesis in an annulus.
[0052] FIGS. 55 and 56 illustrate various embodiments of the protrusions and receiving elements when the prosthesis is not expanded.
[0053] FIG. 57 is a cut-away view of an embodiment of expanding the prosthesis.
[0054] FIGS. 58 and 59 illustrate an embodiment of an expansion tool.
[0055] FIGS. 60 and 61 illustrate another embodiment of an expansion tool.
[0056] FIGS. 62 and 63 illustrate various embodiments of the protrusions and receiving elements when the prosthesis is expanded.
[0057] FIG. 64 is a cut-away view of fixturing the prosthesis to a biological mass.
[0058] FIGS. 65-68 illustrate an embodiment of a method and assembly for fixturing the prosthesis to a biological mass.
[0059] FIG. 69 is a cut-away view of positioning the second prosthesis onto the first prosthesis with a solid view of the second prosthesis.
[0060] FIG. 70 is a cut-away view of attaching the second prosthesis to the first prosthesis.
[0061] FIGS. 71-77 are exploded views of various embodiments of attaching the second prosthesis to the first prosthesis.
[0062] FIG. 78 is an exploded view of an embodiment of attaching the second prosthesis to an adapter and attaching the adapter to the first prosthesis.
[0063] FIGS. 79 and 80 illustrate cross-sections C-C and D-D, respectively, from FIG. 78 .
[0064] FIG. 81 is a top view of an embodiment of the first prosthesis with the second prosthesis attached thereto.
[0065] FIGS. 82-84 illustrate an embodiment of a method of removing the second prosthesis from the first prosthesis.
DETAILED DESCRIPTION
[0066] FIGS. 1 and 2 illustrate an embodiment of a biologically implantable first prosthesis 2 . The first prosthesis 2 can have a wall 4 . The wall 4 can have material strength and dimensions known to one having ordinary skill in the art to make the first prosthesis resiliently expandable. The wall 4 can have an open form or spiral longitudinal cross-section, as shown in FIG. 1 . The longitudinal cross-section can be perpendicular to a central longitudinal axis 6 .
[0067] The wall 4 can have a first terminal end 8 and a second terminal end 10 . Each end 8 and 10 can be defined from a midpoint 12 of the wall 4 to a first terminus 14 or a second terminus 16 of the wall 4 at the respective end 8 or 10 . The wall 4 can have an end difference length 18 . The end difference length 18 can be the shortest angular length from the first terminus 14 to the second terminus 16 . The wall 4 can also have a leading edge 20 and a trailing edge 22 . The leading edge 20 and trailing edge 22 can be substantially perpendicular to the longitudinal axis 6 . The first prosthesis 2 can have a circumference equivalent to a wall length 24 minus an end difference length 18 . The wall 4 can have a wall height 25 . The wall height can be from about 3.18 mm (0.125 in.) to about 12.7 mm (0.500 in.), for example about 8.26 mm (0.325 in.). The wall 4 can also be void of any attachment device with which to fix one end 8 or 10 of the wall 4 to the other end 8 or 10 of the wall 4 . The wall 4 can made from stainless steel alloys, nickel titanium alloys (e.g., Nitinol), cobalt-chrome alloys (e.g., ELGILOY® from Elgin Specialty Metals, Elgin, Ill.; CONICHROME® from Carpenter Metals Corp., Wyomissing, Pa.), polymers such as polyester (e.g., DACRON® from E. I. Du Pont de Nemours and Company, Wilmington, Del.), polypropylene, polytetrafluoroethylene (PTFE), expanded PTFE (ePTFE), polyether ether ketone (PEEK), nylon, extruded collagen, silicone, radiopaque materials or combinations thereof. Examples of radiopaque materials are barium, sulfate, titanium, stainless steel, nickel-titanium alloys and gold.
[0068] FIGS. 3 and 4 illustrate an embodiment of the first prosthesis 2 that can be mechanically expandable. A first protrusion 26 and a second protrusion 28 at the first terminal end 8 can extend from the wall 4 . The protrusions 26 and 28 can extend perpendicular to the wall 4 or perpendicular to the longitudinal axis 6 . The protrusions 26 and 28 can be tabs, brads, extensions, balls, rods or a combination thereof. The protrusions can have a protrusion depth 30 sufficient to retain the wall 4 .
[0069] The wall 4 can also have a first receiving element 32 and a second receiving element 34 at the second terminal end 10 that receive or engage the first protrusion 26 and the second protrusion 28 , respectively. The wall 4 can also have more or less (e.g., one or zero) receiving elements 32 or 34 . The receiving elements 32 and 34 can be holes in the wall 4 . The receiving elements 32 and 34 can also be divets, dimples, hooks, slots, or a combination thereof. The protrusions 26 and 28 and receiving elements 32 and 34 can act together as a stop, or an interference fit, to prevent the first prosthesis 2 from circumferentially extending or decreasing beyond desired limits.
[0070] FIGS. 5 and 6 illustrate an embodiment of the first prosthesis 2 that can have protrusions 26 and receiving elements 32 that can be dimples. The protrusions 26 and receiving elements 32 can be in a first row 36 , a second row 38 , and additional rows 40 . The protrusions 26 can also be in a first column 42 , a second column 44 , and additional columns 46 . The receiving elements 32 can have a receiving element depth 46 within the same range of sizes as the protrusion depth 36 , above.
[0071] FIGS. 7 and 8 illustrate an embodiment of the first prosthesis 2 that can have the protrusions 26 and 28 extending from the first terminus 14 substantially at a tangent to the wall 4 . The protrusions 26 and 28 can be rods 48 with balls 50 at the ends of the rods 48 . The receiving elements 32 and 34 can extend from the second terminus 16 substantially at a tangent to the wall 4 . The receiving elements 32 and 34 can be collars 52 for receiving the balls 50 . The wall 4 can have a longitudinal cross-section in the shape of a circular open curve, as shown in FIG. 7 . A circumferential gap 54 can exist between the first terminus 14 and the second terminus 16 .
[0072] FIGS. 9 and 10 illustrate an embodiment of the first prosthesis 2 that can have different embodiments of protrusions 26 and 28 and receiving elements 32 and 34 . The first prosthesis 2 of FIGS. 9 and 10 can also have a wall angle 56 relative to the longitudinal axis 6 controlled by the dimensions of the protrusions 26 and 28 and receiving elements 32 and 34 and the locations of the protrusions 26 and 28 and receiving elements 32 and 34 on the wall 4 . The wall angle 56 can be from about 10° to about 60°, more narrowly from about 20° to about 45°, for example about 25°. The protrusions 26 and 28 and the receiving elements 32 and 34 can be located along the trailing edge 22 , the leading edge 20 or therebetween.
[0073] FIGS. 11 and 12 illustrate an embodiment of the first prosthesis 2 with the wall 4 having a bottom segment 58 and a top segment 60 . The first prosthesis 2 can be deformably circumferentially expandable. The bottom segment 58 can have the wall angle 56 relative to the longitudinal axis 6 . The angle between the bottom segment 58 and the top segment 60 can be a joint angle 62 . The joint angle 62 can be from about 90° to about 180°, more narrowly from about 90° to about 160°, for example about 120°. The wall 4 can also have a first steering groove 64 that can extend over the length of the bottom segment 58 . The wall 4 can also have a second steering groove 66 that can extend over a portion of the length of the bottom segment 58 . The grooves 64 and 66 can help angularly align, with respect to the longitudinal axis 6 , a second prosthesis 68 that can be attached to the first prosthesis 2 . The grooves 64 and 66 can also prevent the rotation of the first prosthesis 2 with respect to the second prosthesis 68 . The second groove 66 can also help to longitudinally align the second prosthesis 68 .
[0074] The first prosthesis 2 can also have engagement elements, for example top magnets 70 in the top segment 60 and bottom magnets 72 in the bottom segment 58 . The magnets 70 and 72 can have a magnet height 74 , a magnet width 76 and a magnet length 78 . The magnets 70 and 72 can be rare earth, high strength-type magnets. The magnets can be made from neodymium-iron-boron and can be encapsulated in a coating made from PTFE (e.g., TEFLON® (from E. I. Du Pont de Nemours and Company, Wilmington, Del.), PEEK, a similarly inert and stable biocompatible polymer, or a combination thereof. A radiopaque material can also be added to the coating. The top and/or bottom magnets 70 and/or 72 can be customized to allow for only one angular orientation of the second prosthesis 68 by changing the polarity of one or an irregular number of magnets 70 and/or 72 (e.g., positive) to be different from the polarity of the remaining magnets 70 and/or 72 (e.g., negative).
[0075] In one example, 24 magnets 70 can be evenly distributed around the circumference of the first prosthesis 2 . The magnet heights 74 can be about 3.175 mm (0.125 in.). The magnet widths 76 can be about 3.175 mm (0.125 in.). The magnet lengths 78 can be about 1.59 mm (0.0625 in.).
[0076] FIGS. 13 and 14 illustrate an embodiment of the first prosthesis 2 similar to the embodiment illustrated in FIGS. 11 and 12 . The present embodiment of the first prosthesis 2 can have a cloth sewing surface 80 . The magnets 70 can be square or rectangular in cross-section (as shown in FIGS. 11 and 12 ) or oval or circular in cross-section (as shown in FIGS. 13 and 14 ). The wall 4 can also be multiple segments 58 and 60 , as shown in FIGS. 11 and 12 , or a single segment, as shown in FIGS. 13 and 14 .
[0077] FIG. 15 illustrates an embodiment of the first prosthesis 2 similar to the embodiment illustrates in FIGS. 11 and 12 . The first prosthesis 2 in the present embodiment can also be mechanically and/or resiliently circumferentially expandable.
[0078] FIGS. 16-18 illustrate deformable embodiments of the first prosthesis 2 . In an unexpanded state, the first prosthesis 2 can have an unexpanded diameter 82 . The embodiment of the first prosthesis 2 in FIG. 16 can have a smooth wall 4 , thereby relying on hoop strain to expand. In FIG. 17 , the embodiment can have an accordianed wall 4 with multiple pleats or folds 84 . The folds 84 can open or unfold to maximize circumferential expansion of the wall 4 during use. The embodiment of the first prosthesis 2 in FIG. 18 can have a single large fold 84 for the same purpose as the folds 84 shown in FIG. 17 . FIG. 19 illustrates a deformable embodiment of the first prosthesis 2 in an expanded state. A radial force, as shown by arrows, directed away from the longitudinal axis 6 can expand the first prosthesis 2 to an expanded diameter 86 . Materials and dimensions of the first prosthesis 2 can be selected by one having ordinary skill in the art to permit the ratio of the unexpanded diameter 82 to the expanded diameter 86 to be from about 0% to about 50%, more narrowly from about 5% to about 20%, yet more narrowly from about 9% to about 12%, for example about 9.5%.
[0079] FIG. 20 illustrates a length of the wall 4 that can have a first fixturing device connector 88 and a second fixturing device connector 90 . The fixturing device connectors 88 and 90 can be ports or holes in the wall 4 . The fixturing device connectors 88 and 90 can be ovular and can have a fixturing device connector height 92 and a fixturing device connector length 94 . The fixturing device connector height 92 can be from about 0.51 mm (0.020 in.) to about 3.18 mm (0.125 in.), more narrowly from about 1.0 mm (0.040 in.) to about 1.5 mm (0.060 in.), for example about 1.3 mm (0.050 in).
[0080] FIG. 21 illustrates a length of the wall 4 that can have first, second, and additional fixturing device connectors 88 , 90 and 96 . The fixturing device connectors 88 , 90 and 96 can be circular in shape. FIG. 22 illustrates a length of the wall 4 that can have the fixturing device connectors 88 , 90 and 96 attached to the leading and trailing edges 20 and 22 . The fixturing device connectors 88 , 90 and 96 can be made from fabric or metal, for example polymers such as polyester (e.g., DACRON® from E. I. Du Pont de Nemours and Company, Wilmington, Del.), polypropylene, PTFE, ePTFE, nylon, extruded collagen, silicone, stainless steel alloys, nickel-titanium alloys (e.g., Nitinol), cobalt-chrome alloys (e.g., ELGILOY® from Elgin Specialty Metals, Elgin, Ill., CONICHROME® from Carpenter Metals Corp., Wyomissing, Pa.) or combinations thereof. Variously shaped and configured fixturing device connectors 88 , 90 and 96 can be on the same wall 4 .
[0081] FIG. 23 illustrates a length of the wall 4 that can have the receiving elements 32 and 34 . The receiving elements 32 and 34 can be ports or holes in the wall 4 . The receiving elements 32 and 34 and the fixturing device connectors 88 , 90 and 96 can be the same element. The receiving elements 32 and 34 can have a first setting position 98 and a first neck 100 at one end of the first setting position 98 . The first setting position 98 can have a setting position length 102 from about 4 mm (0.2 in.) to about 10 mm (0.4 in.), for example about 6.3 mm (0.25 in.). The first neck 100 can have a neck width 104 . The first neck 100 can be at a first end of a second setting position 106 . The receiving elements 32 and 34 can have more or less than two setting positions 98 and 106 (e.g., one or zero). At a second end of the second setting position 106 , the second setting position 106 can have a second neck 108 . The second neck 108 can be at a first end of a final stop position 110 . The final stop position 110 can have a final stop length 112 .
[0082] The first and second setting positions 98 and 106 can lead to the first and second necks 100 and 108 , respectively, with a ramp angle 114 . The stop position 110 and the second setting position 106 can lead to the second 108 and first necks 100 , respectively, with a stop angle 116 .
[0083] FIG. 24 illustrates narrowing oval or teardrop-shaped receiving elements 32 and 34 . FIG. 25 illustrates rectangular receiving elements 32 and 34 .
[0084] FIG. 26 illustrates the receiving element 32 that can be in the shape of a collar or sleeve. The receiving element 32 can be attached by a connection zone 118 to a rod (not shown) extending from the wall 4 or to the wall 4 itself. The receiving element 32 can have first wedges 120 and second wedges 122 . The length between the closest point of the first wedges 120 or of the second wedges 122 can be the neck width 104 . The wedges 120 and 122 can revolve around the entire receiving element 32 , thereby forming a single, circular first wedge 120 and a single, circular second wedge 122 (when seen in three-dimensions).
[0085] A receiving element shaftway 124 can be open at one end of the receiving element 32 . The receiving element 32 can have a first narrowing 126 near the connection zone 118 and a second narrowing 128 near the receiving element shaftway 124 . FIG. 27 illustrates the receiving element 32 that can have the wedges 120 and 122 shaped as scales or stop tabs.
[0086] A length of the wall 4 that can have protrusions 26 and 28 is illustrated in FIG. 28 . The protrusions 26 and 28 , shown alone in various embodiments in FIGS. 29 and 25 , can be made from an extension 130 and a cuff 132 . The extension 130 can be shaped cylindrically or, as shown in FIG. 30 , as a shaft with a triangular cross-section. The extension 130 can have an extension height 134 and an extension width 136 . The extension height 134 can be from about 0.51 mm (0.020 in.) to about 2.54 mm (0.100 in.), for example about 1.3 mm (0.050 in.). The final stop length 112 can be from about the extension width 136 to about 10 mm (0.4 in.), for example about 6.3 mm (0.25 in.).
[0087] The cuff 132 can be shaped as a circle or a square and can be substantially flat in depth. The cuff 132 can have a cuff height 138 and a cuff width 140 . The cuff height 138 can be from about the fixturing device connector height 92 to about 5.08 mm (0.200 in.), for example about 2.0 mm (0.080 in). The cuff width 140 can be within the range for the cuff height 138 , above.
[0088] FIG. 31 illustrates a length of the wall 4 having the protrusions 26 and 28 formed from tabs cut out of the wall 4 . Cut holes 142 can exist in the wall 4 where the material in the protrusions 26 and 28 was located in the wall 4 before being cut out.
[0089] FIG. 32 illustrates a length of the wall 4 that can have a first set and a second set of protrusions 26 and 28 extending from the wall 4 . The wall 4 can have a wall radius of curvature 144 . The protrusions 26 and 28 can have protrusion radii of curvature 146 . The protrusion radii of curvature 146 can be from about the wall radius of curvature 144 to infinity.
[0090] FIG. 33 illustrates a length of the wall 4 that can have an engagement element 148 . The engagement element 148 can be shaped as a lip and wrapped around the protrusion 26 . The engagement element 148 can enable the first prosthesis 2 to self-engage the second prosthesis 68 . For example, the engagement element 148 can snap-fit to the second prosthesis 68 .
[0091] FIG. 34 illustrates the first terminal end 8 and the second terminal end 10 . The second terminal end 10 can have a first guide 150 and a second guide 152 that can wrap around the leading edge 20 and the trailing edge 22 , respectively, of the first terminal end 8 . The first terminal end 8 can slide angularly, with respect to the longitudinal axis 6 , within the guides 150 and 152 . The guides 150 and 152 can also minimize the risk of the first terminal end 8 moving too far away from or becoming misaligned from the second terminal end 10 .
[0092] FIGS. 35-43 illustrate embodiments of the first prosthesis 2 at a latitudinal cross-section. The latitudinal cross-section can be a cross-section parallel with the longitudinal axis 6 . FIG. 35 illustrates an embodiment with the wall 4 having a corrugated latitudinal cross-section. FIG. 36 illustrates an embodiment with the wall 4 having a straight latitudinal cross-section, parallel with the longitudinal axis 6 .
[0093] FIG. 37 illustrates an embodiment having the trailing edge 22 angled toward the longitudinal axis 6 at the wall angle 56 . FIG. 38 illustrates an embodiment having the trailing edge 22 angled away from the longitudinal axis 6 at the wall angle 56 .
[0094] FIG. 39 illustrates an embodiment having a wall 4 convex toward the longitudinal axis 6 . The wall 4 can be straight or have a lateral convex radius of curvature 154 . FIG. 40 illustrates an embodiment having a wall 4 concave toward the longitudinal axis 6 . The wall 4 can have a lateral concave radius of curvature 156 within the same range as the lateral convex radius of curvature 154 .
[0095] FIG. 41 illustrates an embodiment having a wall 4 with a top segment 60 , a middle segment 158 and a bottom segment 58 . The top segment 60 and leading edge 20 can be angled away from the longitudinal axis 6 . The bottom segment 58 and trailing edge 22 can be angled away from the longitudinal axis 6 . The middle segment 158 can remain parallel to the longitudinal axis 6 .
[0096] FIG. 42 illustrates an embodiment having the top segment 60 and the leading edge 20 that can be angled toward the longitudinal axis 6 . The bottom segment 58 and trailing edge 22 can also be angled toward the longitudinal axis 6 . The middle segment 158 can remain parallel to the longitudinal axis 6 .
[0097] FIGS. 43 and 44 illustrate an embodiment of the wall 4 that can have a bottom segment 58 that can extend from the wall 4 at a retainer angle 160 with respect to the longitudinal axis 6 from about 0° to about 90°, more narrowly from about 10° to about 50°, for example about 30°. The bottom segment 58 can also have cuts 162 , shown in FIG. 44 . The cuts 162 can minimize stresses when the bottom segment 58 fans away from the middle segment 158 . The bottom segment 58 can also act as a retention element, extending beyond the typical trailing edge 22 and stabilizing the first prosthesis 2 after the first prosthesis 2 is implanted.
[0098] FIG. 45 illustrates a cross-section of the wall 4 that can have a fabric covering 164 , for example polyester (e.g., DACRON® from E. I. du Pont de Nemours and Company, Wilmington, Del.), polypropylene, PTFE, ePTFE, nylon, extruded collagen, silicone or combinations thereof. The fabric can be attached to the wall 4 at a first attachment point 166 and a second attachment point 168 . The bare area of the wall between the attachment points 166 and 168 can be the engagement surface 170 . The second prosthesis 68 can engage the first prosthesis 2 at the engagement surface 170 .
[0099] FIG. 46 illustrates a cross-section of the wall 4 covered entirely by the covering 164 . The second prosthesis 68 can also engage the first prosthesis 2 at the engagement surface 170 covered by the covering 164 .
[0100] FIG. 47 illustrates a length of wall 4 with the engagement element 148 , shaped as an open lip, on the leading edge 20 . The engagement element 148 can be turned toward the longitudinal axis 6 and toward the trailing edge 22 . FIG. 48 illustrates the engagement element 148 turned away from the longitudinal axis 6 and toward the trailing edge 22 .
[0101] FIGS. 49 and 50 illustrate an embodiment of the first prosthesis 2 that can have a first length 172 , a second length 174 and a third length 176 . The lengths 172 , 174 and 176 can be separated by cuts 162 in the wall 4 . The engagement element 148 on the first length 172 and third length 176 can turn toward the longitudinal axis 6 . The top and middle segments 60 and 158 of the first length 172 and the third length 176 can be bent away from the bottom segment 58 as shown by the arrows in FIG. 50 . The top and middle segments 60 and 158 of the second length 174 can be similarly bent but in the opposite direction to the top and middle segments 60 and 158 of the first and third lengths 172 and 176 . The engagement element 148 on the second length 174 can turn away from the longitudinal axis 6 . A lip length 178 can be the length between a first lip edge 180 of the engagement element 148 on the first length 172 or third length 176 and a second lip edge 182 of the engagement element 148 on the second length 174 . The lip length 178 can be small enough to form a seam, crease or seat 184 to aid in seating, receiving and engaging a second prosthesis.
[0102] FIG. 51 illustrates a length of the wall 4 that can have the lengths 172 , 174 and 176 . The engagement elements 148 on the first length 172 and third length 176 can turn away from the longitudinal axis 6 . The engagement element 148 on the second length 174 can turn toward the longitudinal axis 6 . The engagement element 148 can then engage a second prosthesis on both sides of the wall 4 .
[0103] FIG. 52 illustrates an embodiment that can have springs 186 . One segment of each spring 186 can be a latch 188 . The springs 186 can have windings 190 around a rail 192 fixed under the engagement element 148 . The springs 186 can also have retaining legs 194 pressed against the wall 4 . The latches 188 can be biased to contract, as shown by arrows 196 , against the wall 4 . The latches 188 can be held in the uncontracted position shown in FIG. 52 by interference beams 198 . The interference beams 198 can be directly or indirectly rigidly attached to each other at a proximal end (in the direction of arrows 200 ) to minimize the interference beams 198 from deflecting under the force, shown by arrows 196 , from the latches 188 . The interference beams 198 can be removed, as shown by arrows 200 , allowing the latches 188 to contract, as shown by arrows 196 , against, for example, the second prosthesis, once the second prosthesis is positioned within the reach of the latches 188 .
[0104] Method of Making
[0105] The wall 4 can be made from methods known to one having ordinary skill in the art. For example, the wall 4 can be molded or machined. The engagement element 148 , the corrugation and any other bends in the wall 4 can be formed (e.g., pressure formed), molded or machined into the wall 4 or bent into the metal with methods known to one having ordinary skill in the art.
[0106] The protrusions 26 and 28 and the receiving elements 32 and 34 (e.g., at the connection zone 118 ) can be fixed to the to the wall 4 or formed of the wall 4 by crimping, stamping, melting, screwing, gluing, welding, die cutting, laser cutting, electrical discharge machining (EDM) or a combination thereof. Cuts 162 and holes in the wall 4 can be made by die cutting, lasers or EDM.
[0107] Any part of the first prosthesis 2 , or the first prosthesis 2 as a whole after assembly, can be coated by dip-coating or spray-coating methods known to one having ordinary skill in the art. One example of a method used to coat a medical device for vascular use is provided in U.S. Pat. No. 6,358,556 by Ding et al. and hereby incorporated by reference in its entirety. Time release coating methods known to one having ordinary skill in the art can also be used to delay the release of an agent in the coating. The coatings can be thrombogenic or anti-thrombogenic. For example, coatings on the inside of the first prosthesis 2 , the side facing the longitudinal axis 6 , can be anti-thrombogenic, and coatings on the outside of the first prosthesis, the side facing away from the longitudinal axis 6 , can be thrombogenic.
[0108] The first prosthesis 2 can be covered with a fabric, for example polyester (e.g., DACRON® from E. I. du Pont de Nemours and Company, Wilmington, Del.), polypropylene, PTFE, ePTFE, nylon, extruded collagen, silicone or combinations thereof. Methods of covering an implantable device with fabric are known to those having ordinary skill in the art.
[0109] Method of Use
[0110] The first prosthesis 2 can be introduced in an unexpanded state to an antechamber 202 adjacent to a targeted valve annulus 204 by methods known to one having ordinary skill in the art. FIG. 53 illustrates positioning and lowering, as shown by the arrows, the first prosthesis 2 to the annulus 204 . Because of the collapsible and expandable nature of the first prosthesis 2 , the procedure of implanting the first prosthesis 2 can be accomplished thorascopically, endoscopically and/or endoluminally. The first prosthesis 2 can be placed accurately enough into the annulus 204 so that the first prosthesis 2 does not block vessel openings in chambers neighboring the annulus 204 (e.g., the openings for the coronary vessels) and does not fall out of the annulus 204 (e.g., into a chamber of the heart, a ventricle for example). The annulus 204 can have an initial annulus diameter 206 . FIG. 54 illustrates positioning and seating the first prosthesis 2 .
[0111] When the first prosthesis 2 is completely unexpanded, the protrusion 26 and the receiving element 32 can be aligned as illustrated in FIGS. 55 and 56 . As shown in FIG. 55 , the extension 130 can be located in the first setting position 98 . As shown in FIG. 56 , the ball 50 can be located in the first setting position 98 .
[0112] The first prosthesis 2 can be circumferentially expanded, as illustrated by the arrows in FIG. 57 . The prosthesis can have an expanded annulus diameter 208 . The expanded annulus diameter 208 can be from about 5 mm (0.2 in.) to about 40 mm (1.6 in.), depends on the size of the initial annulus diameter 206 , and can be influenced by other anatomy, anomalies (e.g., narrowing, stenosis) and age (e.g., pediatric sizing). An expansion tool 210 can be used to expand the first prosthesis 2 . Examples of the expansion tool 210 include a balloon, back sides of a clamp jaws, or a flexible plug assembly as shown in FIGS. 58-61 . Another example of the expansion tool 210 is disclosed in U.S. Pat. No. 5,984,959 to Robertson et al. which is herein incorporated by reference in its entirety.
[0113] FIG. 58 illustrates a flexible plug 212 that can be cylindrical and have a static plate 214 on a first side 216 . The plug 212 can be made from polymers, for example polyurethane or silicone. The plug 212 can have a hole 218 in the center of the plug 212 . A rigid inner tube 220 can pass through the hole 218 and be tied into a knot or pull against a washer 222 on the first side 216 . A squeeze plate 224 can be fixedly attached to an end of a rigid outer tube 226 . The outer tube 226 can be larger than the inner tube 220 , and the inner tube 220 can slide through the outer tube 226 . A force in the direction of the plug 212 can be applied to the outer tube 226 , as shown by arrows 228 . A force in the direction away from the plug 212 can be applied to the inner tube 220 , as shown by arrows 230 . The plug can have a resting diameter 232 when no forces are applied.
[0114] Once the forces shown by the arrows 228 and 230 are applied to the plug 212 , the plug 212 can deform away from the tubes 220 and 226 , as shown by arrows 234 and illustrated in FIG. 59 . Once deformed, the plug 212 can have an expanded diameter 236 . The resting diameter 232 and the expanded diameter 236 can be sized appropriately to the dimensions of the first prosthesis 2 . The deformation of the plug 212 can also create forces in the same direction as the arrows 234 . When the forces shown by the arrows 228 and 230 are removed, the plug 212 can return to the shape shown in FIG. 58 .
[0115] FIG. 60 illustrates another embodiment of the plug 212 . The plug 212 can have a recessed top surface 238 and a recessed bottom surface 240 . A top perimeter 242 and a bottom perimeter 244 can be angled from the recessed surfaces 238 and 240 to meet a wall 246 of the plug 212 . The squeeze plate 224 and the static plate 214 can both be conically or partially conically shaped to fit the perimeters 242 and 244 of the plug 212 . As shown in FIG. 61 , when the forces shown by the arrows 228 and 230 are applied, the plug wall 246 can expand radially and maintain a flat surface.
[0116] When the first prosthesis 2 is completely expanded, the protrusion 26 and the receiving element 32 can be aligned as illustrated in FIGS. 62 and 63 . As shown in FIG. 62 , the extension 130 can be located in the final stop position 110 . As shown in FIG. 63 , the ball 50 can be located in the final stop position 110 . The interference fit caused by the stop angle 116 and neck width 104 of the second neck 108 can prevent the protrusion 26 from re-entering the second setting position 106 . In addition, when expanded the first prosthesis frictionally engages the annulus, expanding the annulus diameter. When expanded, the first prosthesis 2 can also trap vascular plaque between the wall 4 and the perimeter of the annulus 204 . The first prosthesis 2 can also be partially expanded, forcing the protrusion 26 into the second setting position 106 .
[0117] Fixturing devices 248 can be used to fix the first prosthesis 2 through the fixturing device connectors 88 to the biological mass of the annulus 204 , as shown in FIG. 64 . Examples of fixturing devices 88 are sutures, clips, staples, pins and combinations thereof.
[0118] FIGS. 65-68 illustrate one embodiment of a method of fixing the first prosthesis 2 to the annulus 204 . FIG. 65 illustrates an embodiment of a fixturing device assembly 250 . The fixturing device assembly 250 can have a needle 252 . The needle 252 can be curved or have a curved tip. The needle 252 can also be attached at a proximal end to a distal end of a line 254 . The proximal end of the needle 252 can also be attached directly to the can 256 without the line 254 or formed as the can 256 . A proximal end of the line 254 can be attached to a can 256 . The can 256 can be a flexible cylindrical storage device, for example a coil. The can 256 can removably hold the fixturing device 248 . The fixturing device 248 can have a fixturing element 258 , for example a wire or fiber. The fixturing element 258 can have a ball 260 at a first end and a radially expandable portion 262 at a second end. The fixturing device 248 can also have a pledget 264 on the fixturing element 258 between the ball 260 and the expandable portion 262 .
[0119] The fixturing device assembly 250 can be positioned so the needle 252 is adjacent to the fixturing device connector 88 , as shown by arrows 266 . The needle 252 can then be pushed through the fixturing device connector 88 and the annulus 204 , as shown by arrow 268 in FIG. 66 . The needle 252 can then be pulled away from the annulus 204 , as shown by arrow 270 in FIG. 67 . The can 256 can follow the path of the needle 252 through the annulus 204 , as shown by arrow 272 . The pledget 264 can also be larger than the fixturing device connector 88 , and the pledget 264 can provide an interference fit against the fixturing device connector 88 . The needle 252 can continue to be pulled away from the annulus 204 , pulling the can 256 out of the annulus 204 , as shown by arrow 274 in FIG. 68 . The interference fit of the pledget 264 against the fixturing device connector 88 can provide a resistive force holding the fixturing device 248 and causing the fixturing element 258 to slide out of the can 256 as the needle 252 is pulled away from the annulus 204 . The radially expandable portion 262 can then radially expand, thereby causing the first prosthesis 2 and the annulus 204 to be fixed between the pledget 264 and the radially expandable portion 262 .
[0120] The inner surface of the can 256 can be designed—for example by coiling, corrugation, or other roughening—to adjust the friction between the inner surface of the can 256 and the fixturing device 248 . This friction can influence the amount of resistive force necessary to remove the fixturing device 248 from the can 256 . The resistive force can be larger than about the force necessary to have the fixturing device 248 fall out of the can 256 before the fixturing device 248 has passed through the annulus 104 . The resistive force can also be less than about the force necessary to deform the pledget 264 sufficient to pull the pledget 256 through the fixturing device connector 88 . The resistive force can be, for example, about 1.1 N (0.25 lbs.).
[0121] A second prosthesis 68 can then be positioned on the engagement element 148 , as shown by the arrows in FIG. 69 . Once seated on the engagement element 148 , the second prosthesis 68 can then be engaged by the first prosthesis 2 , as shown in FIG. 70 . Examples of second prostheses 68 include a connection adapter and a heart valve crown with leaflets 276 , for example, U.S. Pat. No. 6,371,983 to Lane which is herein incorporated by reference in its entirety.
[0122] FIG. 71 illustrates another embodiment of the heart valve assembly 278 with the second prosthesis 68 . The first prosthesis 2 can have a tapered wall 280 to provide a longitudinal stop and to guide insertion of the second prosthesis 68 into the first prosthesis 2 , as shown by arrows 282 . The tapered wall 280 can also push back the annulus 204 , maintaining the expanded annulus diameter 208 when the second prosthesis 68 is engaged in the first prosthesis 2 . The second prosthesis 68 can have spring lock tabs 284 to fix to the engagement element 148 . The spring lock tabs 284 can angle outwardly from the longitudinal axis 6 . The first and second prostheses 2 and 68 can have first and second prosthesis diameters 288 and 290 , respectively. The first prosthesis diameter 288 can be larger than the second prosthesis diameter 290 . FIG. 72 illustrates the embodiment of the heart valve assembly 278 of FIG. 71 , however the second prosthesis diameter 290 can be larger than the first prosthesis diameter 288 , and the spring lock tabs 284 can angle inwardly toward the longitudinal axis 6 . The first prosthesis 2 and the second prosthesis 68 act to maintain the expanded annular lumen diameter 208 .
[0123] FIG. 73 illustrates another embodiment of the heart valve assembly 278 with a second prosthesis 68 that can have fixation points 286 that align with fixation points 286 on the first prosthesis 2 to allow insertion of sutures, grommets, clips 292 or pins 294 through the aligned fixation points 286 to fix the first prosthesis 2 to the second prosthesis 68 .
[0124] FIG. 74 illustrates another embodiment of the heart valve assembly 278 with a multi-lobed stiffening ring 296 that can be placed near the edge of the second prosthesis 68 as shown by arrows 298 . The second prosthesis 68 can have several flaps 300 . The flaps 300 can wrap around the stiffening ring 296 , as shown by arrows 302 . The wrapped stiffening ring 296 can increase the rigidity of the second prosthesis 68 and can engage the engagement element 148 .
[0125] FIG. 75 illustrates yet another embodiment of the heart valve assembly 278 with an embodiment of the first prosthesis 2 equivalent to the embodiment in FIG. 52 . The second prosthesis 68 can have latch openings 304 to receive the latches 188 . When the second prosthesis 68 is lowered into the first prosthesis 2 , the interference beams 198 can be removed, as shown by arrows 200 . The latches 188 can then contract onto the latch openings 304 .
[0126] FIG. 76 illustrates an embodiment of the heart valve assembly 278 with an embodiment of the first prosthesis 2 equivalent to the embodiment in FIGS. 11 and 12 . The second prosthesis can have a rib 306 to fit within the groove 64 . The second prosthesis 68 can also have an upper arm 308 that can have a top magnet 70 and a lower arm 310 that can have a bottom magnet 72 . The magnets 70 and 72 in the second prosthesis 68 can have polarities opposite of the polarities of the corresponding magnets 70 and 72 in the first prosthesis 2 . FIG. 77 illustrates an embodiment of the heart valve assembly 278 with an embodiment of the first prosthesis equivalent to the embodiment in FIGS. 13 and 14 .
[0127] FIG. 78 illustrates an embodiment of the heart valve assembly 278 with an adapter 312 connecting the second prosthesis 68 to the first prosthesis 2 . The adapter 312 can have spring lock tabs 284 to fix to the engagement element 148 , and the adapter 312 can have a stop ridge 314 to position the adapter 312 against the wall 4 .
[0128] The adapter 312 can also have fixation points 286 that align with other fixation points 286 on the second prosthesis 68 to allow insertion of sutures, grommets, clips, pins, or the fixturing devices 248 , through the aligned fixation points 286 to fix the adapter 312 to the second prosthesis 68 . The second prosthesis 68 can also be lowered into the top of the adapter 312 as shown by arrow 316 . The adapter 312 can attach to the inside or outside of the first or second prosthesis 2 or 68 depending on the dimensions and the orientation of the attachment apparatus (e.g., unidirectional clips).
[0129] The adapter 312 can also have multiple shapes of cross-sections, as shown in FIGS. 79 and 80 . As shown in FIG. 79 , cross-section C-C can have three lobes 318 and three scallops 320 . One scallop 320 can be between each lobe 318 . Cross-section C-C can be the same as the cross-section of the second prosthesis 68 where the second prosthesis 68 engages the adapter 312 . As shown in FIG. 80 , cross-section D-D can be circular. Cross-section D-D can be the same as the cross-section of the first prosthesis 2 where the first prosthesis 2 engages the adapter 312 .
[0130] FIG. 81 illustrates a second prosthesis 68 received by a first prosthesis 2 . The second prosthesis 68 can have three lobes 318 . The second prosthesis can have a scallop 320 between each two lobes 318 . The scallop gap 322 between each scallop 320 and the wall 4 can be covered by a fabric during use of the prostheses 2 and 68 .
[0131] FIG. 82 illustrates that a lever device 324 , for example a clamp or scissors, can be forced, as shown by arrows, into the scallop gap 322 . As illustrated in FIG. 83 , once legs 326 of the lever device 324 are placed next to two scallops 320 , the lever device 324 can be squeezed, as shown by arrows, thereby crushing the second prosthesis 68 and separating it from the first prosthesis 2 . As illustrated in FIG. 84 , the second prosthesis 68 can be removed from the first prosthesis 2 , as shown by arrows, once the second prosthesis 68 is separated from the first prosthesis 2 . Once the second prosthesis 68 is removed, a new second prosthesis 68 can be added as described above. Leaflet failure can be fixed easily and inexpensively by implanting a new second prosthesis 68 . Circumferential expansion of the first prosthesis 2 and replacement of the second prosthesis 68 to account for pediatric expansion of the valve can also be performed easily and inexpensively.
[0132] It is apparent to one skilled in the art that various changes and modifications can be made to this disclosure, and equivalents employed, without departing from the spirit and scope of the invention. Elements shown with any embodiment are exemplary for the specific embodiment and can be used on other embodiments within this disclosure.
[0133] Although the present disclosure has been described with reference to preferred embodiments, workers skilled in the art will recognize that changes can be made in form and detail without departing from the spirit and scope of the present disclosure. | A heart valve assembly includes a first annular prosthesis for implantation within a tissue annulus, a second valve prosthesis, and a plurality of magnets on the first and second prostheses to secure the second prosthesis to the first prosthesis. In one embodiment, the magnets are arranged to allow the second prosthesis to be secured to the first prosthesis in a predetermined angular orientation. During use, the first annular prosthesis is implanted into the annulus, and the second valve prosthesis is inserted into the annulus. The magnets orient the second prosthesis relative to the first prosthesis to align the second prosthesis with the first prosthesis in a predetermined angular orientation; and secure the second prosthesis to the first prosthesis in the predetermined angular orientation. | 0 |
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Continuation Application claiming priority from a United States Utility Application having Ser. No. 11/195,090 filed Aug. 1, 2005.
FEDERALLY SPONSORED RESEARCH
[0002] Not applicable.
REFERENCE TO A MICROFICHE APPENDIX
[0003] Not applicable.
FIELD OF INVENTION
[0004] The present invention relates to the field of portable pneumatic dispensers capable of being manufactured at a reduced cost and allowing fast assembly.
BACKGROUND OF THE INVENTION
[0005] Many current art compressed gas dispensers, particularly the models manufactured by Genuine Innvations, Inc, in Tucson, Ariz. U.S.A. are manufactured to dispense a non-threaded neck compressed gas cartridge, a threaded neck compressed gas cartridge or capable of dispensing both cartridge species within the same dispense.
[0006] One feature of current art compressed gas dispensers is a lance housing that has been used in part to contain the high pressure from a compressed gas cartridge. Historically, lance housings have been manufactured from metal such as brass. A lance housing also provides an excellent recess or pocket for a seal that is used to contain the compressed gas in a lanced cartridge. A lance housing can feature internal threads that are used to mate with a compressed gas cartridge also exhibiting a threaded portion. A lance housing sometimes exhibits no threads to mate with a compressed gas cartridge.
[0007] U.S. Pat. No. 6,843,388 by Hollars titled Compressed gas cartridge dispensing system allowing interchangeable use of different capacity compressed gas cartridges and novel storage feature teaches some methods of how a non-threaded neck compressed gas cartridge can be dispensed as well as teaches an additional method of how a threaded neck compressed gas cartridge can be dispensed. Additionally, the terminology from the U.S. Pat. No. 6,843,388 is carried over into this application in an effort to maintain consistency for ease of understanding. FIGS. 1-7 PRIOR-ART are borrowed directly from the U.S. Pat. No. 6,843,388 to exemplify common designs and uses of compressed gas cartridge lance housings.
[0008] Common types of lance housings such as exemplified in FIG. 1 PRIOR-ART illustrate an internally threaded exemplary lance housing 44 and in FIG. 2 PRIOR-ART illustrate a non-threaded exemplary lance housing 44 ′. Threaded lance housing 44 illustrated in FIG. 1 PRIOR-ART will accept a compressed gas cartridge 33 exhibiting a comparable male thread on its cartridge neck used to threadably draw cartridge 33 into the piercing lance. Exemplified in FIG. 3 PRIOR-ART is male threaded compressed gas cartridge 33 threaded into internally threaded lance housing 44 as part of dispenser head 23 . Slightly visible in FIG. 3 PRIOR-ART is a piercing lance that has been drawn into the puncture surface of the compressed gas cartridge as a result of the threaded connection thus the compressed gas cartridge has been harnessed or lanced.
[0009] Additionally, threaded lance housing 44 can be used to dispense a non-threaded neck compressed gas cartridge 49 of one volume and 49 ′ of a greater volume with the use of a cartridge-retaining container 22 as illustrated in FIGS. 4 and 5 PRIOR-ART. Both FIGS. 4 and 5 PRIOR-ART are borrowed from the U.S. Pat. No. 6,843,388. The compressed gas cartridge neck portion in both FIGS. 4 and 5 PRIOR-ART are small enough in diameter thus allowing the non-threaded necks to clear threaded lance housing portion 44 without an interference fit.
[0010] Non-threaded lance housing 44 ′ exemplified in FIG. 2 PRIOR-ART is illustrated with a cartridge-retaining container 22 threadably attached in FIGS. 6 and 7 PRIOR-ART and will accept a compressed gas cartridge by incorporating cartridge-retaining container 22 to draw the cartridge into the piercing lance. FIGS. 6 and 7 PRIOR-ART exemplify two different capacity compressed gas cartridges 49 and 49 ′ exhibiting non-threaded necks. A cartridge typically increases in length and diameter as the internal volume increases.
[0011] One United States patent that exemplifies the background relating to the present invention is U.S. Pat. No. 5,544,670 titled Inflation device for an inflatable article of manufacture and adaptor therefore by Philips et al. Applicant is a co-inventor on this patent as well. The technology in this patent has been common since as early as 1993. FIG. 8 PRIOR-ART is borrowed from the Philips et al. patent and illustrates a side view cross-section exemplary dispensing device. The relevant text in the Philips et al. specification to this figure states the following: “ . . . lance supporting member 44 includes a cylindrical extension 43 which defines an interior area 45 .” This is an excellent example of a prior-art non-threaded lance housing that represents how the industry has designed and manufactured lance housings.
[0012] The lance housing has traditionally provided means for mounting a cartridge piercing lance as well as providing a recess for a compressed gas cartridge face seal, neck seal, or combination of both. A typical compressed gas cartridge piercing lance is made from steel, perhaps hardened, and is press-fit into a void within a lance housing. Current practice utilizes both solid lance designs and hollow lance designs with reliable success. Also common is to insert a brass lance housing into an injection molded dispensing head and retain the lance housing in place with hardware such as a roll pin or utilize one-way barb features on the outside of a lance housing.
[0013] The present invention minimizes the assembly time of a dispenser head. Additional features are integrated into a molded dispenser head thus requiring fewer components to accomplish a useable dispenser thus reducing manufacturing costs. Reliance on conformable plastic allows for relaxed dimensional tolerances. This method of making a dispenser head can equally apply to threaded or non-threaded lance housings.
[0014] Prior-art lance housings are mostly realized as providing a bore that a puncturing lance presses into resulting in a lance is contained in the metal of a lance housing. Additionally, a retaining undercut pocket has traditionally been machined into a lance housing to locate the compressed gas cartridge seal.
[0015] The present invention illustrates an exemplary mounting of a compressed gas cartridge puncturing lance in the main housing of a dispensing head. Additionally, a compressed gas cartridge seal retaining undercut is created by the insertion of a rigid seal retaining element into a molded dispensing head. One obvious advantage to this method of manufacturing a compressed gas cartridge seal pocket by the insertion of a retaining element is that a molder would find molding a feature difficult or impossible. Typically, injection molding retaining undercuts such as described is not a moldable feature.
[0016] The following embodiments will describe the afore-mentioned prior-art and the present invention. Additionally, with the aid of figures, one skilled in the art will be able to understand and appreciate the embodiments to follow.
OBJECTS AND ADVANTAGES
[0017] Accordingly, several objects and advantages of the present invention will be presented in the following paragraphs followed by a thorough disclosure of each aspect in the accompanying embodiments in the DETAILED DESCRIPTION.
[0018] In light of the above-mentioned problems, it is therefore an object of the present invention to provide a quick method of manufacturing a compressed gas dispenser therefore reducing material and labor expenses.
[0019] Further, it is another object of the present invention to provide means for additional safety venting without increasing the number of parts.
[0020] It is another object of the present invention to reduce manufacturing tolerances of components without sacrificing quality.
[0021] Another object of the present invention is to make a functional compressed gas dispenser lighter in weight than current designs.
[0022] Another object of the present invention is to provide a lance housing arrangement capable of disassembly for service or component replacement.
[0023] It is another object of the present invention to utilize as little metal as possible in a lance housing and incorporate as many features as possible with an injection molded dispensing head.
[0024] Another object of the present invention is to provide means for mounting a compressed gas cartridge piercing lance into a plastic dispensing head.
[0025] Additionally, another object of the present invention is to provide means for a compressed gas cartridge seal retaining undercut through this new style of lance housing.
[0026] Further objects and advantages will become apparent in the following paragraphs. Solely and in combination, the above objects and advantages will be illustrated in the exemplary figures and accompanying embodiments to follow.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The figures are exemplary of different embodiments of the present invention. Each illustration conveys the invention and is not to be considered as limiting, rather, exemplary to the scope and spirit of the present invention. Like components in the figures share identical numbering.
[0028] FIG. 1 PRIOR-ART illustrates a side sectional view of an exemplary internally threaded lance housing, intended to illustrate general lance housing construction, borrowed from U.S. Pat. No. 6,843,388;
[0029] FIG. 2 PRIOR-ART illustrates a side sectional view of an exemplary non-threaded lance housing, intended to illustrate general lance housing construction, borrowed from U.S. Pat. No. 6,843,388;
[0030] FIG. 3 PRIOR-ART illustrates a side section view of the exemplary internally threaded lance housing from FIG. 1 mated with a threaded neck compressed gas cartridge, borrowed from U.S. Pat. No. 6,843,388;
[0031] FIG. 4 PRIOR-ART illustrates a side section view of the exemplary internally threaded lance housing from FIG. 1 shown lancing a non-threaded compressed gas cartridge with the use of a cartridge-retaining container, borrowed from U.S. Pat. No. 6,843,388;
[0032] FIG. 5 PRIOR-ART illustrates a side section view of the exemplary internally threaded lance housing from FIG. 1 shown lancing a non-threaded compressed gas cartridge with the use of a cartridge-retaining container, borrowed from U.S. Pat. No. 6,843,388;
[0033] FIG. 6 PRIOR-ART illustrates a side sectional view of the exemplary non-threaded lance housing from FIG. 2 shown lancing a non-threaded compressed gas cartridge with the use of a cartridge-retaining container, borrowed from U.S. Pat. No. 6,843,388;
[0034] FIG. 7 PRIOR-ART illustrates a side sectional view of the exemplary non-threaded lance housing from FIG. 2 shown lancing a non-threaded compressed gas cartridge with the use of a cartridge-retaining container, borrowed from U.S. Pat. No. 6,843,388;
[0035] FIG. 8 PRIOR-ART illustrates a side sectional view of an exemplary compressed gas cartridge dispenser detailing a typical lance assembly, borrowed from U.S. Pat. No. 5,544,670;
[0036] FIG. 9 illustrates a side view of an exemplary lance housing assembly in a compressed gas cartridge dispensing head, in accordance with an embodiment of the present invention;
[0037] FIG. 10 illustrates a cross-section view A-A of the exemplary lance housing assembly in a compressed gas cartridge dispensing head from FIG. 9 , in accordance with an embodiment of the present invention;
[0038] FIG. 11 illustrates an exploded view of the exemplary lance housing assembly in a compressed gas cartridge dispensing head from FIG. 9 , in accordance with an embodiment of the present invention;
[0039] FIG. 12 illustrates an exploded view of an exemplary compressed gas cartridge dispensing head, in accordance with an embodiment of the present invention;
[0040] FIG. 13 illustrates a side view of the exemplary compressed gas cartridge dispensing head from FIG. 12 , in accordance with an embodiment of the present invention;
[0041] FIG. 14 illustrates a cross-sectional view A-A of the exemplary compressed gas cartridge dispensing head from FIG. 13 , in accordance with an embodiment of the present invention;
[0042] FIG. 15 illustrates a cross-sectional view of an exemplary seal retaining element comprising retaining barbs, in accordance with an embodiment of the present invention;
[0043] FIG. 16 illustrates a cross-sectional view of an exemplary seal retaining element comprising external mounting threads, in accordance with an embodiment of the present invention;
[0044] FIG. 17 illustrates a cross-sectional view of an exemplary seal retaining element comprising a groove for retaining a pin(s), in accordance with an embodiment of the present invention;
[0045] FIG. 18 illustrates a cross-sectional view of an exemplary dispensing head comprising the barbed seal retaining element introduced in FIG. 15 , in accordance with an embodiment of the present invention;
[0046] FIG. 19 illustrates a cross-sectional view of an exemplary dispensing head comprising external mounting threads on the seal retaining element introduced in FIG. 16 , in accordance with an embodiment of the present invention;
[0047] FIG. 20 illustrates a cross-sectional view of an exemplary dispensing head comprising the grooved seal retaining element for retaining pins introduced in FIG. 17 , in accordance with an embodiment of the present invention.
DETAILED DESCRIPTION
[0048] The following paragraphs will detail, at minimum, the best mode of the present invention. The exemplary figures and description of the invention as it is exemplified in each figure is representative of the current invention and the scope of the invention disclosure is not intended to be limited by the exemplary teachings. Like physical structure in different figures share the same identifying numbers.
[0049] FIG. 9 illustrates a side view of an exemplary lance housing assembly in a compressed gas cartridge dispensing head, in accordance with an embodiment of the present invention. An inlet end 900 and an outlet end 901 of a compressed gas cartridge dispensing head 905 are shown. Inlet end 900 is the end of the dispensing head that contains the compressed gas cartridge lancing means. Outlet end 901 is illustrated as truncated downstream from the compressed gas cartridge lancing means. The aforementioned prior-art examples offer some suggestion as to the type of apparatus that outlet end 901 can be fluidly attached to and there are numerous other applications both in the known and new art that outlet end 901 can fluidly attach. Apparatus examples are portable blowers, inflation heads having valve attachments, portable pressure regulators, dump valves such as for fire extinguishing, and other devices.
[0050] An external thread 915 is illustrated on dispensing head 905 and connects with a cartridge-retaining cup that will be illustrated in some following FIGS.
[0051] FIG. 10 shows a cross-sectional view A-A taken from FIG. 9 and illustrates an exemplary lance housing assembly, in accordance with an embodiment of the present invention. Dispensing head 905 comprises a tapered cartridge lead-in at inlet end 900 that can help guide insertion of a compressed gas cartridge by a user. Within inlet end 900 , a hollow compressed gas cartridge piercing lance 930 hereinafter lance, is press-fit into dispensing head 905 . A ring of lance barbs 935 maintain lance 930 in position in dispensing head 905 . A compressed gas cartridge seal 920 situates substantially about lance 930 . A seal retaining element 910 ( FIGS. 9 and 10 ) is inserted through window 911 and is maintained in place by an interference fit with at least some portion of window 911 . A retaining undercut 925 maintains compressed gas cartridge seal 920 into position thus creating a pocket for seal 920 .
[0052] FIG. 11 illustrates an exploded view of the exemplary lance housing assembly in the compressed gas cartridge dispensing head from FIG. 9 , in accordance with an embodiment of the present invention. Clearly visible in this view is window 911 for seal retaining element 910 . Window 911 can be on one side of dispensing head 905 or continue through dispensing head 905 . The truncation of outlet end 901 is also more visible in this view.
[0053] FIG. 12 illustrates an exploded view of an exemplary compressed gas cartridge dispensing head, in accordance with an embodiment of the present invention. A dispensing head 1200 features a window 1215 similar to window 911 from FIGS. 9-11 . Window 1215 is taller in this embodiment to allow a threaded seal retaining element 1220 to have an adequate thread range 1225 for safe connection to a threaded compressed gas cartridge (not shown in this view). The rectangular profile of seal retaining element 1220 prevents rotation upon lancing a compressed gas cartridge.
[0054] Alternate views of FIG. 12 in FIGS. 13 and 14 illustrate dispensing head 1200 comprising a tapered cartridge lead-in at inlet end 1201 that can help guide insertion of a compressed gas cartridge by a user. Within inlet end 1201 , a hollow compressed gas cartridge piercing lance 1205 hereinafter lance, is press-fit into dispensing head 1200 . One skilled in the art could readily recognize that a solid compressed gas piercing lance is another minor deviation from the exemplified embodiment. A ring of lance barbs 1210 maintain lance 1205 in position in dispensing head 1200 . Compressed gas cartridge seal 920 situates substantially about lance 1205 . A seal retaining element 1220 is inserted through window 1215 and is maintained in place by an interference fit with at least some portion of window 1215 . A retaining undercut 1221 maintains compressed gas cartridge seal 920 into position thus creating a pocket for seal 920 .
[0055] In accordance with an embodiment of the present invention, FIG. 15 illustrates a cross-sectional view of an exemplary barbed seal retaining element 1505 comprising a one-way push in retaining feature. A barb or series of barbs 1500 allow the seal retaining element to press into a dispensing head from its inlet end and provide a retaining undercut 1501 for the compressed gas cartridge seal when in the installed position. An internal bore 1502 is illustrated smooth and can additionally be threaded thus allowing a user to lance a larger group of compressed gas cartridges. Additionally exemplified in FIG. 18 is a dispensing head assembly comprising barbed seal retaining element 1505 installed through an inlet end 1800 of a molded dispensing head.
[0056] Another embodiment in FIG. 16 includes using external threads on a seal retaining element 1605 as a retaining means in a dispensing head. An external thread 1600 can either cut into or mate with opposite gender threads in a dispensing head. Additionally, a retaining undercut 1601 for the compressed gas cartridge seal is provided when in the installed position. An internal bore 1602 is illustrated smooth and can additionally be threaded thus allowing a user to lance a larger group of compressed gas cartridges. Additionally exemplified in FIG. 19 is a dispensing head assembly comprising external mounting threads on seal retaining element 1605 installed through an inlet end 1900 of a molded dispensing head.
[0057] An additional embodiment in FIG. 17 includes using a stake pin retaining slot as a means to retain the seal retaining element into a dispensing head. A stake pin retaining slot 1700 allows a fastener such as a roll pin to be inserted through an opening on a dispensing head and catch with stake pin retaining slot 1700 . Additionally, a retaining undercut 1701 for the compressed gas cartridge seal is provided when in the installed position. An internal bore 1702 is illustrated smooth and can additionally be threaded thus allowing a user to lance a larger group of compressed gas cartridges. Additionally exemplified in FIG. 20 is a dispensing head assembly comprising grooved retaining seal element 1705 installed through an inlet end 2000 of a molded dispensing head. A roll pin 2001 or comparable staking pin inserts through a hole in dispensing head, and at least partially engages pin retaining slot 1700 thus keeping grooved retaining seal element 1705 situated within dispensing head. | The present invention minimizes the assembly time of a dispenser head by inserting a rigid seal retaining element. The seal retaining element comes in different configurations thus allowing a variety of compressed gas cartridge dispensing options. Additional features are integrated into a molded dispenser head thus requiring fewer components to accomplish a useable dispenser thus reducing manufacturing costs. Reliance on conformable plastic allows for relaxed dimensional tolerances. This method of making a dispenser head can equally apply to threaded or non-threaded lance housings. | 8 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an oil filling device, and in particular to an oil filling device that enables adjustment of relative direction and distance between an oil filling funnel of the device and an engine oil filling hole so as to allow the oil filling device to accommodate various models and types of engine.
2. The Related Arts
Vehicles, such as automobiles and motorcycles, comprise an engine that is provided with an oil pan having a small filling opening. It is often that over-filling of oil result in spillage or overflowing of the oil outside the engine, causing environmental pollution when falling to the ground. In addition, when a large amount of oil is filled into an oil tube in a short period, air bubbles are generated and stuck in the oil tube so that the air may not be discharged and thus block oil from being further filled. This affects the efficiency and smoothness of the operation of filling oil and may often lead to spillage of oil due to negligence.
Further, the location and direction of the oil filling opening are different from each other for different engines. Heretofore, oil filling devices are generally not adjustable and are thus not fit to the oil filling openings of various models and types of vehicles. Consequently, it is common to change the oil filling devices when it is attempted to fill oil to different models or types of vehicles. This is certainly very troublesome. Apparently, the conventional, non-adjustable oil filling devices can be further improved.
Thus, it is desired to provide an oil filling device that overcomes the above discussed problems.
SUMMARY OF THE INVENTION
An object of the present invention is to provides an oil filling device, which enables adjustment of direction of an oil filling funnel with respect to an oil filling hole of an engine and also enables adjustment of distance between the oil filling funnel and the engine oil filling hole, whereby the oil filling device is applicable to filling oil to various models and types of engines.
To achieve the above object, the present invention provides an oil filling device, which comprises an oil filling funnel, an extendable tube assembly, a direction adjustment assembly, and a coupling assembly. The oil filling funnel is mounted to a first end of the extendable tube assembly. The extendable tube assembly has a second end mounted to the direction adjustment assembly. The direction adjustment assembly is mounted to the coupling assembly that is attachable to an oil filling hole of an engine. The direction adjustment assembly enables adjustment of the direction of the extendable tube assembly and the oil filling funnel with respect to the engine, while the extendable tube assembly allows the oil filling funnel to be selectively moved toward or away from the oil filling hole. Thus, the oil filling device may accommodate various heights and angles of engine oil filling hole and allows filling of oil into the engine to be conducted in a smoother manner.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be apparent to those skilled in the art by reading the following description of a preferred embodiment thereof, with reference to the attached drawings, wherein:
FIG. 1 is an exploded view showing an oil filling device according to the embodiment of the present invention;
FIG. 2 is a perspective view, in an assembled form, of the oil filling device according to the present invention;
FIG. 3 is a cross-sectional view of a portion of the oil filling device of the present invention, particularly showing details of an extendable tube assembly of the oil filling device;
FIG. 4 is a cross-sectional view of a portion of the oil filling device of the present invention, particularly showing a direction adjustment assembly to which a coupling assembly is attached;
FIG. 5 is a cross-sectional view showing a locking cap of the coupling assembly of the oil filling device according to the present invention;
FIG. 6 is a side elevational view illustrating an extension operation of the oil filling device according to the present invention;
FIG. 7 is a side elevational view illustrating a direction adjustment operation of the oil filling device according to the present invention; and
FIG. 8 is a perspective view illustrating an application of the oil filling device according to the present invention to filling oil into an engine.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
With reference to the drawings and in particular to FIGS. 1 and 2 , the present invention provides an oil filling device, which comprises a oil filling funnel 10 , which has a lower end connected to an insertion connector 11 . The insertion connector 11 has a lower end connected to an angled fitting 12 .
An extendable tube assembly 20 comprises a first tubular member 21 that has a first end 211 . The angled fitting 12 has a free end that is fit into the first end 211 of the first tubular member 21 of the extendable tube assembly 20 . The first tubular member 21 has a free end to which an end connector 22 is mounted. The end connector 22 comprises a tapered bore 221 formed therein and the tapered bore 221 receives a second tubular member 23 to telescopically extend therethrough. The tapered bore 221 comprises a tapered section that receives and retains therein a conical wedge block 24 having a C-shaped cross-section. A fastening element 25 , which is internally threaded, is mounted to an external thread 222 . After the second tubular member 23 is telescopically received and sets a desired length, the fastening element 25 is rotated to urge the conical wedge block 24 further into the tapered bore 221 so as to get compressed and securely fix the first tubular member 21 and the second tubular member 23 to each other to thereby achieve the functions of extension for adjustment and also fixing at selected length.
A direction adjustment assembly 30 comprises a rotary adjustment knob 31 , a fastening knob 32 , and a T-shaped fitting 33 . The T-shaped fitting 33 has a top portion through which a lateral passage 331 is formed to receive the rotary adjustment knob 31 to extend therethrough in such a way as to maintain the rotary adjustment knob 31 rotatable. The rotary adjustment knob 31 has an end that receives, engages, and fixes an external thread 232 formed on a free end of the second tubular member 23 . The rotary adjustment knob 31 has an opposite free end forming an external thread 314 with which an internal thread 321 formed in the fastening knob 32 engages, whereby when the rotary adjustment knob 31 is rotated to a desired angular position, the fastening knob 32 is rotated to tightly abut the T-shaped fitting 33 so as to secure the position of the rotary adjustment knob 31 .
A coupling assembly 40 comprises a locking cap 41 , in which an axially extending insertion bore 411 is formed. The insertion bore 411 receives the T-shaped fitting 33 to inset therein. In operation, the insertion bore 411 is set in communication with an interior of an engine 50 (see FIG. 8 ). The locking cap 41 as a lower end forming an external thread 412 that is engageable with an internal thread 511 of an oil filling opening 51 of the engine 50 (see FIG. 8 ). The external thread 412 can be further provided with a gasket ring 42 set around an outer circumference of the external thread. The locking cap 41 has a side portion in which an inverted T-shaped vent hole 43 is formed, whereby a first opening 431 of the inverted T-shaped vent hole 43 is in communication with the interior of the engine 50 , a second opening 432 is formed in a side surface of the locking cap 41 to communicate with the outside atmosphere, and a third opening 433 is formed in a top of the locking cap 41 to communicate with the outside atmosphere so as to enable an oil filling operation to be done in a smoother manner without jamming.
Referring to FIGS. 3 and 4 , as discussed above, the oil filling device according to the present invention comprises an oil filling funnel 10 having a lower end to connect to an insertion connector 11 and the insertion connector 11 has a lower end connected to the angled fitting 12 , whereby a funnel hole 101 , a connector hole 111 , and an angled fitting hole 121 are in communication with each other. The angled fitting 12 has a free end that is fit to the first end 211 of the first tubular member 21 of the extendable tube assembly 20 in such a way that the angled fitting hole 121 is in communication with a first bore 212 of the first tubular member 21 . The first tubular member 21 has a free end to which an end connector 22 is mounted.
The end connector 22 comprises an internal tapered bore 221 , which telescopically receives the second tubular member 23 to extend therethrough. The tapered bore 221 comprises a tapering section that receives and retains the conical wedge block 24 therein. The fastening element 25 comprises an internally threaded hole 251 and the end connector 22 has an outer circumference that forms an external thread 222 engaging the internally threaded hole 251 of the fastening element 25 .
Once the second tubular member 23 is extended or retracted to a desired length, the fastening element 25 is rotated to drive the conical wedge block 24 further into the tapered bore 221 so as to compress the wedge block and thus fix the first tubular member 21 and the second tubular member 23 to each other to achieve the functions of extension for adjustment and also fixing at selected length.
The first bore 212 of the first tubular member 21 is in communication with a second bore 231 of the second tubular member 23 .
The direction adjustment assembly 30 that comprises the rotary adjustment knob 31 , the fastening knob 32 , and the T-shaped fitting 33 is structured so that the T-shaped fitting 33 has a top portion forming the lateral passage 331 to receive the rotary adjustment knob 31 to extend therethrough. The T-shaped fitting 33 also has a lower portion forming a vertical passage 332 extending from and in communication with the lateral passage 331 . The rotary adjustment knob 31 is rotatable and has an end (leading end) forming an internally-threaded hole 311 that engages an external thread 232 formed at a free end of the second tubular member 23 .
The rotary adjustment knob 31 has an opposite end (tailing end) forming a hole 312 in communication with the internally-threaded hole 311 . The rotary adjustment knob 31 has a circumferential wall in which a plurality of through holes 313 is formed to correspond to the vertical passage 332 to communicate with the vertical passage 332 . The rotary adjustment knob 31 comprises an external thread 314 formed at the tailing end to engage an internal thread 321 formed in the fastening knob 32 , whereby when the rotary adjustment knob 31 is set at a desired angular position, the fastening knob 32 is rotated to abut against the T-shaped fitting 33 and thus secure the rotary adjustment knob 31 in position.
The coupling assembly 40 comprises the locking cap 41 , which forms an axially extending insertion bore 411 to receive and retain the T-shaped fitting 33 in such a way that the vertical passage 332 is in communication with the insertion bore 411 . The insertion bore 411 is set in communication with the engine 50 (see FIG. 8 ). The locking cap 41 has a lower end forming an external thread 412 engageable with the internal thread 511 of the oil filling opening 51 of the engine 50 (see FIG. 8 ).
Oil is filled through the funnel hole 101 of the oil filling funnel 10 , passing through the connector hole 111 , the angled fitting hole 121 , the first bore 212 , the tapered bore 221 , the second bore 231 , the internally-threaded hole 311 , the hole 312 , the through holes 313 , the vertical passage 332 , and the insertion bore 411 to get into the interior of the engine 50 .
Referring to FIG. 5 , the locking cap 41 has a side portion forming the inverted T-shaped vent hole 43 , whereby the first opening 431 of the inverted T-shaped vent hole 43 is in communication with the engine 50 , the second opening 432 is formed in a side surface of the locking cap 41 to communicate with the outside atmosphere, and the third opening 433 is formed in the top of the locking cap 41 to communicate with the outside atmosphere so as to enable an oil filling operation to be done in a smoother manner without jamming.
Referring to FIG. 6 , the extendable tube assembly 20 has two opposite ends that are respectively connected to the oil filling funnel 10 and the direction adjustment assembly 30 . The second tubular member 23 of the extendable tube assembly 20 is telescopically received through the end connector 22 and the first tubular member 21 , whereby after being set to a desired length, the fastening element 25 is rotated to fix the first tubular member 21 and the second tubular member 23 to each other achieve the functions of extension for adjustment and also fixing at selected length.
Referring to FIGS. 1 and 7 , according to the present invention, the rotary adjustment knob 31 of the direction adjustment assembly 30 is kept in a selectively rotatable condition and the leading end of manner of the rotary adjustment knob 31 is coupled to the second tubular member 23 through mating engagement with the external thread 232 of the second tubular member. Further, the rotary adjustment knob 31 comprises an external thread 314 formed at the tailing end thereof to mate the internal thread 321 of the fastening knob 32 , whereby when the rotary adjustment knob 31 is rotated to a desired angular position, generally with respect to the T-shaped fitting 33 and the coupling assembly 40 , the fastening knob 32 can be fastened to abut the T-shaped fitting 33 and thus secure the rotary adjustment knob 31 in position.
Referring to FIGS. 1 and 8 , the coupling assembly 40 is provided for coupling to the oil filling opening 51 of an engine 50 and the relative angle (or direction) between the direction adjustment assembly 30 with respect to the coupling assembly 40 can be adjusted as desired to set the direction the extendable tube assembly 20 and the oil filling funnel 10 with respect to the coupling assembly and the engine. The extendable tube assembly 20 can be adjusted to set the relative distance between the oil filling funnel 10 and the oil filling opening 51 of the engine 50 to selectively make them approaching to each other or distant from each other. In this way, the oil filling device can accommodate various heights and angles of oil filling opening 51 to allow the filling of oil into an engine to be done more smoothly.
It is apparent that the oil filling device according to the present invention enables adjustment of position and direction thereof with respect to an engine where oil is to be filled with the oil filling device and such adjustment is done with a novel and unique structure and arrangement that has never been proposed and known.
Although the present invention has been described with reference to the preferred embodiment thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims. | An oil filling device includes an oil filling funnel, an extendable tube assembly, a direction adjustment assembly, and a coupling assembly. The oil filling funnel is mounted to a first end of the extendable tube assembly. The extendable tube assembly has a second end mounted to the direction adjustment assembly. The direction adjustment assembly is mounted to the coupling assembly that is attachable to an oil filling hole of an engine. The direction adjustment assembly enables adjustment of the direction of the extendable tube assembly and the oil filling funnel with respect to the engine, while the extendable tube assembly allows the oil filling funnel to be selectively moved toward or away from the oil filling hole. Thus, the oil filling device may accommodate various heights and angles of oil filling hole of engine and allows filling of oil into the engine to be conducted in a smoother manner. | 1 |
BACKGROUND OF THE INVENTION
This invention relates to self adjusting tongs, and is particularly suitable for, but not limited to, tongs for household use in the grasping of food and for other purposes.
Various types of tongs for household use and other purposes are known in the art. Such tongs are exemplified by the following references:
U.S. Pat. No. 3,376,639 S. Pompini
U.S. Pat. No. 2,563,422 T. M. Sabo
U.S. Pat. No. 3,889,995 C. Lin
However, there is need for an inexpensive pair of tongs which is capable of improved grasping of cylindrical or irregularly-shaped objects of varying sizes.
Accordingly, an object of the present invention is to provide improved tongs having self adjusting jaws.
SUMMARY OF THE INVENTION
As herein described, there is provided a pair of self-adjusting tongs, comprising a first stem having a first handle at one end; a first jaw pivotally mounted to the other end of the first stem, for rotation about a first axis transverse to the first stem, said first jaw having an annular grasping portion and a spring portion engaging said first stem; a second stem pivotally mounted to said first stem and having a second handle at one end adjacent the handle of the first stem; a second jaw pivotally mounted to the other end of the second stem, for rotation about a second axis transverse to the second stem, said second jaw having an annular grasping portion and a spring portion engaging said second stem; the spring portions of said first and second jaws interacting with said first and second stems respectively to urge the annular grasping portions of said jaws to rotate about said first and second respective axes through a limited angular range toward each other, while permitting pivoting of said first and second jaws about said first and second axes respectively to enable said jaws to orient themselves in conformity with an object engaged between the jaws when the handles are moved toward each other.
IN THE DRAWING
FIG. 1 is a perspective view of a pair of self-adjusting tongs according to a preferred embodiment of the invention, in a partially open position;
FIG. 2 is a top plan view showing the tongs in closed position, the bottom plan view being identical;
FIG. 3 is a front elevation view thereof, the rear elevation view being a mirror image;
FIG. 4 is a right side elevation view thereof; and
FIG. 5 is a left side elevation view thereof.
DETAILED DESCRIPTION
As shown in the drawings, and particularly FIG. 1, the self-adjusting tongs 10 comprise a first stem 11 having a first handle 12 at one end thereof, and a second stem 13 having a second handle 14 at one end thereof, adjacent the first handle 12. The stems 11 and 13 are pivotally mounted to each other by means of a pivot pin 15.
A first jaw 16 is pivotally mounted to the other end of the stem 11, by means of a pivot pin 18. Similarly, a second jaw 17 is pivotally mounted to the other end of the stem 13, by means of a pivot pin 19.
The first jaw 16 has an annular grasping portion 20, preferably made of metal, and a spring metal extension 21. The extension 21 extends from the pivot axis 18, which is transverse to the longitudinal dimension of the stem 11, in the direction of the handle 12, and terminates in a loop 22 which surrounds and is slidably movable along the stem 11.
Similarly, the jaw 17, which is preferably but not necessarily identical to the jaw 16, has an annular grasping portion 23 and an arcuate spring metal portion 24 which extends from the transverse pivot pin 19 in the direction of the handle 14, and terminates in a loop 25 which surrounds and is slidably movable along the stem 13.
The spring metal portions 21 and 24 are arcuately shaped so that when the grasping portions 20 and 23 of the jaws 16 and 17 are not in engagement with an object, the loops 22 and 25 are relatively proximate to the pivots 18 and 19, and the jaws 16 and 17 are rotated about the pivots 18 and 19 respectively, through a limited angular range, so as to bring the distal ends 26 and 27 of said jaws relatively close together.
When the handles 12 and 14 are brought toward each other so as to cause the grasping portions 20 and 23 of the jaws 16 and 17 to engage an object, the distal ends 26 and 27 of the jaws are moved away from each other, to cause the jaws to rotate about the axes 18 and 19 so that the curves of the arcuate portions 21 and 24 are flattened, causing the loops 22 and 25 to slide along the stems 11 and 13, away from the pivots 18 and 19.
This rotational movement of the annular grasping portions 20 and 23 of the jaws 16 and 17 enables the jaws to orient themselves in conformity with an object engaged between the jaws when the handles 12 and 14 are moved toward each other.
When the handles 12 and 14 are moved away from each other to release the object from the grasping portions 20 and 23, the spring metal arcuate portions 21 and 24 return to their normal shape, causing the loops 22 and 25 to move toward the pivots 18 and 19, and rotating the grasping portions 20 and 23 of the jaws 16 and 17 so as to again bring the distal ends 26 and 27 thereof closer together, thus facilitating the grasping of another object.
Thus, the grasping portions 20 and 23 of the jaws 16 and 17 are inclined toward each other when the tongs are not in use; and the rotation of said portions results in resilient deformation of the arcuate portions 21 and 24 when the tongs are used, the resiliency of the arcuate portions 21 and 24 serving to return the grasping portions 20 and 23 to their initial orientation after the object grasped thereby is released.
The stems 11 and 13 are preferably made of steel, while the jaws 16 and 17 are preferably stamped from sheet metal having resilient qualities.
The annular grasping portions 20 and 23 of the jaws 16 and 17 have inner recessed parts 28 and 29 and outer raised parts 30 and 31 respectively.
The outer raised parts 30 and 31 of the annular grasping portions 20 and 23 have surfaces knurled to provide a multiplicity of pyramid-shaped elements for providing enhanced grasping action.
A double row of needles (not visible in the drawing) extends from the rasised part 30 in the direction of the annular grasping portion 23; while a similar double row of needles 32 extends from the raised part 31 of the grasping portion 23, toward the grasping portion 20. | A pair of self adjusting tongs for household use, particularly for grasping food, wherein the jaws are independently rotatable within a limited angular range about corresponding pivot axes, with each jaw being spring-loaded by an arcuate spring extension of the jaw, the end of the spring extension constituting a loop which surrounds and slides along the corresponding stem of the tongs. | 1 |
CROSS-REFERENCE TO RELATED APPLICATIONS AND PRIORITY CLAIM
[0001] This application is a non-provisional of U.S. patent application Ser. No. 61/510,998, filed Jul. 22, 2011, the disclosure of which is incorporated by reference herein in its entirety.
BACKGROUND
[0002] This disclosure relates generally to the field of imaging and more particularly to enhancing images obtained from Geiger mode Avalanche PhotoDiode detectors using three-dimensional statistical differencing.
[0003] Imaging sensors such as laser radar sensors (LADARs) acquire point clouds of a scene. The point clouds of the scene are then image processed to generate three dimensional (3D) models of the actual environment of the scene. The image processing of the 3D models enhances the visualization and interpretation of the scene. Typical applications include surface measurements in airborne and ground-based industrial, commercial and military scanning applications such as site surveillance, terrain mapping, reconnaissance, bathymetry, autonomous control navigation and collision avoidance and the detection, ranging and recognition of remote military targets.
[0004] Presently there exist many types of LADARs for acquiring point clouds of a scene. A point cloud acquired by a LADAR typically comprise x, y & z data points from which range to target, two spatial angular measurements and strength (i.e., intensity) may be computed. However, the origins of many of the individual data points in the point cloud are indistinguishable from one another. As a result, most computations employed to generate the 3D models treat all of the points in the point cloud the same, thereby resulting in indistinguishable “humps/bumps” on the 3D surface model of the scene.
[0005] Various imaging processing techniques have been employed to reconstruct the blurred image of the scene. The blurring or convolution of the image is a result of the low resolution (i.e., the number of pixels/unit area) of the intensity images at longer distances and of distortion of the intensity image by the LADAR optics and by data processing. Accordingly, the image must be de-blurred (deconvolved).
[0006] Relevant herein, LADARs may comprise arrays of avalanche photodiode (APD) detectors operating in Geiger-mode (hereinafter “GmAPD”) that are capable of detecting single photons incident onto one of the detectors. FIG. 1 diagrammatically depicts a typical GmAPD LADAR 10 including focal plane arrays 12 of avalanche photodiode (APD) detectors 14 operating in Geiger-mode. Integrated timing and readout circuitry (not shown) is provided for each detector 14 . In typical operation, a laser pulse emitted from a microchip laser 16 passes through a bandpass filter 18 , variable divergence optics 20 , a half-wave plate 22 , a polarizing beam splitter 24 , and is then directed via mirrors 26 and 28 through a beam expander 30 and a quarter wave plate 32 . Scanning mirrors 34 then steer the laser pulses to scan the scene 36 of interest. It is noted that the scanning mirrors 34 may allow the imaging of large areas from a single angle of incidence or small areas imaged from a variety of angles on a single pass. Return reflections of the pulse from objects in the scene 36 (e.g., tree and tank) pass in the opposite direction through the polarizing beam splitter 24 , a narrow band filter 38 , and then through a zoom lens 40 onto the detector array 12 . The outputs of the detector array 12 forming a point cloud 42 of XYZ data are then provided to an image processor 44 for viewing on a display 46 .
[0007] More particularly, the operation of a GmAPD LADAR occurs as follows. After the transmit laser pulse leaves the GmAPD LADAR, the detectors 14 are overbiased into Geiger-mode for a short time, corresponding to the expected time of arrival of the return pulse. The window in time when the GmAPD is armed to receive the return pulse is known as the range gate. During the range gate, the GmAPD and its integrated readout circuitry is sensitive to single photons. The high quantum efficiency in the GmAPD results in a high probability of generating a photoelectron. The few volts of overbias ensure that each free electron has a high probability of creating the growing avalanche which produces the volt-level pulse that is detected by the CMOS readout circuitry. This operation is more particularly described in U.S. Pat. No. 7,301,608, the disclosure of which is hereby incorporated by reference herein.
[0008] Unfortunately, during photon detection, the GmAPD does not distinguish among free electrons generated from laser pulses, background light, and thermal excitations within the absorber region (dark counts). High background and dark count rates are directly detrimental because they introduce noise (see, e.g., FIG. 7 of Pat. No. 7,301,608) and are indirectly detrimental because they reduce the effective sensitivity to signal photons that arrive later in the range gate. See generally, M. Albota, “Three-dimensional imaging laser radar with a photon-counting avalanche photodiode array and microstrip laser”, Applied Optics, Vol. 41, No. 36, Dec. 20, 2002, the disclosure of which is hereby incorporated by reference herein. Nevertheless, single photon counting GmAPDs are favored due to efficient use of the power-aperture.
[0009] There presently exist several techniques for extracting the desired signal from the noise in a point cloud acquired by a GmAPD LADAR. Representative techniques include Z-Coincidence Processing (ZCP) that counts the number of points in fixed-size voxels to determine if a single return point is noise or a true return, Neighborhood Coincidence Processing (NCP) that considers points in neighboring voxels, and various hybrids thereof (NCP/ZCP). See P. Ramaswami, “Coincidence Processing of Geiger-Mode 3D Laser Radar Data”, Optical, Society of America, 2006, the disclosure of which is hereby incorporated by reference herein.
[0010] In addition to removal of noise from a point cloud through the use of NCP or ZCP techniques, it is often desirable to enhance the resulting image. Prior art image enhancement techniques include unsharp masking techniques using a highpass filter, techniques for emphasizing medium-contrast details more than large-contrast details using adaptive filters and statistical differential techniques that provide high enhancement in edges while presenting a low effect on homogenous areas.
SUMMARY OF THE INVENTION
[0011] In one embodiment, a method for processing XYZ point cloud of a scene acquired by a GmAPD LADAR is disclosed. The method of this embodiment includes: voxelizing and defocusing the XYZ point cloud obtained from the GmAPD LADAR on a computing device to produce a VD point cloud; and displaying an image of the VD point cloud.
[0012] According to another embodiment, a method for processing a XYZ point cloud of a scene acquired by a GmAPD LADAR is disclosed. The method of this embodiment includes: Z-clipping the XYZ point cloud adaptive histogramming to produce a Z-clipped point cloud; voxelizing and defocusing the XYZ point cloud obtained from the GmAPD LARAR to produce a VD point cloud based upon at least one of desired pixel size, photon spreading, timing accuracy, sensor crosstalk, expected probability of detection or probability of false alarm and the desired sensitivity as may be selected by the operator; thresholding the vD point cloud to produce a first thresholded point cloud; sharpening the first thresholded point cloud in the X-Y plane by highpass filtering to produce a sharpened point cloud; thresholding the sharpened point cloud to produce a second thresholded point cloud; mitigating timing uncertainty in the second thresholded point cloud by deconvolving the second thresholded point cloud in the vertical direction to produce a deconvolved point cloud; thresholding and cleansing the deconvolved point cloud in the vertical direction to produce a thresholded/cleansed point cloud; and displaying an image of the thresholded/cleansed point cloud by counting photons at points in the thresholded/cleansed point cloud.
[0013] According to another embodiment, a system for processing a XYZ point cloud of a scene acquired by a GmAPD LADAR is disclosed. The system of this embodiment includes an image processor for voxelizing and defocusing the XYZ point cloud obtained from the GmAPD LADAR to produce a VD point cloud and a display that displays an image of the VD point cloud.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] For a fuller understanding of the present disclosure and its advantages, reference is now made to the following description, taken in conjunction with the accompanying drawings, in which:
[0015] FIG. 1 is a diagrammatic view of a typical GmAPD LADAR that may be employed by the present invention to acquire an XYZ point cloud representing the image of the scene of interest;
[0016] FIG. 2 is a process flow diagram of the method of the invention implemented on an image processor for display or further processing;
[0017] FIG. 3 is a diagrammatic view of adaptive histogramming;
[0018] FIG. 4 is a diagrammatic view of the Defocusing (low-pass) Matrix employed in the method of the invention; and
[0019] FIG. 5 is a diagrammatic view of the Refocussing (high-pass) Matrix employed in the method of the invention.
[0020] Similar reference characters refer to similar parts throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0021] 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 one or more preferred embodiments of the invention. The scope of the invention should be determined with reference to the claims.
[0022] The apparatus and method of the invention comprises a typical GmAPD LADAR 10 described above in connection with FIG. 1 to acquire a point cloud 42 A of XYZ data of a scene of interest 36 that is provided to an image processor 44 . It shall be understood without departing from the spirit and scope of the invention, that neither the apparatus nor method of the invention is limited to any particular type or brand of GmAPD LADARs 10 .
[0023] The image processor 44 may be embodied in a general purpose computer with a conventional operating system or may constitute a specialized computer without a conventional operating system so long as it is capable of processing the XYZ point cloud 42 A in accordance with the process flow diagram of FIG. 2 . Further, it shall be understood without departing from the spirit and scope of the invention, that neither the apparatus nor the method of the invention is limited to any particular type or brand of image processor 44 .
[0024] As shown in FIG. 2 , a method according to one embodiment includes storing the XYZ point cloud 42 A of data into the memory of the image processor 44 at block 202 . The memory may comprise any type or form of memory. The image processor 44 may comprise a computational device such as application specific integrated circuits (ASIC), or a central processing unit (CPU), digital signal processor (DSP) or field-programmable gate arrays (FGPA) containing firmware or software, that sequentially performs the following computations on the XYZ point cloud 42 A.
[0025] After being stored, the XYZ point cloud 42 A is Z-clipped based on adaptive histogramming at block 202 to form a Z-clipped point cloud 42 B. The Z-clipping performed at block 202 can include, for example, applying histogram equalization in a window sliding over the image pixel-by-pixel to transform the grey level of the central window pixel. However, to reduce the noise enhancement and distortion of the field edge, as shown in FIG. 3 , a contrast-limited adaptive histogram equalization is preferably performed in the Z-direction to clip histograms from the contextual regions before equalization, thereby diminishing the influence of dominate grey levels.
[0026] The Z-clipped point cloud 42 b then, at block 204 , is voxelized and defocused to form a VD point cloud 42 c. Voxelizing a 3D point cloud is known in the art and not discussed further herein. The operations of block 204 can include, for example, utilizing the defocus (low-pass) matrix of FIG. 4 . The matrix shown in FIG. 4 is based upon desired pixel size, photon spreading (i.e., expected dispersion), timing accuracy, sensor crosstalk, expected probability of detection and probability of false alarm and the desired sensitivity (low, medium or high) as may be selected by the operator. Notably, the voxelizing and defocusing in three dimensions eliminates (or substantially reduces) noise and distributes energy to accommodate dispersive targets.
[0027] Referring again to FIG. 2 , the resulting VD point cloud 42 C is thresholded at block 206 to reduce processing time. The resulting thresholded point cloud 42 D is saved in memory for further processing according to the method of the invention. To reduce processing time, the thresholded point cloud 42 D is sharpened in the X-Y plane by a refocus (high-pass) matrix as illustrated in FIG. 5 at block 208 . The resulting sharpened point cloud 42 E can then be thresholded again at block 210 to reduce additional noise around the edges of the scene thereby sharpening the image.
[0028] The resulting thresholded point cloud 42 F can then be deconvolved at block 212 in the vertical Z direction {. . . , −d 2 , −d 1 , −d 0 , +d 0 , +d 1 , +d 2 , . . . } using a spiking function to mitigate timing uncertainty. The resulting deconvolved point cloud 42 G can then by thresholded and cleansed downwardly in the Z direction at block 214 to minimize processing. The result is thresholded/cleansed point cloud 42 H that represents the photons returned from the scene.
[0029] At block 216 , thresholded/cleansed point cloud 42 H representing the photons returned from the scene, are counted at each point in the scene 46 and the resulting image is displayed via display 46 at block 218 . It shall be understood that in various embodiments any of the previously described point clouds could have their photons counted and be displayed.
[0030] The present disclosure includes that contained in the appended claims, as well as that of the foregoing description. Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention.
[0031] Now that the invention has been described, | An apparatus and method for processing of XYZ point clouds obtained from a GmAPD LADAR using low-pass filtering followed by high-pass filtering and deconvolution. | 6 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to a semiconductor laser array device having a plurality of striped channels.
2. Description of the Prior Art
Semiconductor laser devices which are useful as light sources for optical discs, optical information processing systems, etc., are required to produce high output power. However, conventional semiconductor laser devices having a single-lasing filament structure can only produce as low as several tens of mW output power.
In order to produce high output power, semiconductor laser array devices, in which a plurality of semiconductor laser devices are disposed in a parallel manner to achieve an optical phase coupling between the adjacent lasing filaments, have been proposed. However, these semiconductor laser array devices cannot attan a 0°-phase shift between the adjacent lasing filaments in the range of a high output power level.
Experimental data of the inventors indicate that although a Fabry-Perot semiconductor laser array device having three striped channels as lasing filaments attains a 0°-phase shift between the adjacent lasing filaments up to a 20 mW output power as shown in FIG. 3, it cannot attain a 0°-phase shift in a range of higher output power. FIG. 4 indicates that the longitudinal mode of this Fabry-Perot semiconductor laser array device in the range of higher than a 20 mW output power is composed of the main mode and two submodes at the shorter wavelength side of the main mode. The temperature of the center striped channel rises more than that of each of the two outer striped channels as the amount of injection electric current into the laser array device is increased. As the temperature of a semiconductor laser rises, in general, the width of the forbidden band therein becomes smaller and the wavelength of the laser light emitted therefrom becomes longer. Thus, it can be said that the abovementioned main mode indicates a laser light derived from the center striped channel, while the two submodes at the shorter wavelength side of the main mode indicate laser lights which are oscillated, respectively, from the outer striped channels without being synchronized with the laser light from the center striped channel.
SUMMARY OF THE INVENTION
The semiconductor laser array device of this invention which overcomes the above-discussed and numerous other disadvantages and deficiencies of the prior art, comprises a structure for minimizing the dependence of the longitudinal mode of laser oscillation upon the driving electric current, and for attaining laser oscillation with a 0°-phase shift there.
The structure for minimizing the dependence of the longitudinal mode of laser oscillation upon the driving electric current is, in a preferred embodiment, a distributed feedback structure, a distributed Bragg reflection structure or an internal reflection structure.
Thus, the invention described herein makes possible the objects of (1) providing a semiconductor laser array device, having plural striped channels, which attains laser oscillation with a 0°-phase shift between the adjacent striped channels by suppressing a variation in the longitudinal mode of laser oscillation even when the temperature of the laser array device rises as the amount of injection electric current is increased; and (2) providing a semiconductor laser array device which produces laser lights with a 0°-phase shift therebetween up to high output power since the said laser array device has a structure (e.g., a distributed feedback structure, a distributed Bragg reflection structure, an internal reflection structure, etc.) which minimizes the dependence of the longitudinal mode of laser oscillation upon driving electric current.
BRIEF DESCRIPTION OF THE DRAWINGS
This invention may be better understood and its numerous objects and advantages will become apparent to those skilled in the art by reference to the accompanying drawings as follows:
FIG. 1 is a perspective view showing a semiconductor laser array device of this invention.
FIG. 2(a) is a perspective view showing V-channels on the substrate of a semiconductor laser array device of this invention.
FIG. 2(b) is a perspective view showing the semiconductor laser array device having the V-channels shown in FIG. 2(a).
FIG. 3 is a diagram showing the far-field pattern at the time when a conventional semiconductor laser array device attains laser oscillation with a 0°-phae shift between the adjacent striped channels up to a 20 mW output power.
FIG. 4 is a diagram showing the longitudinal mode spectrum in an unsynchronous state created by the conventional semiconductor laser array device shown in FIG. 3 in the range of higher than the 20 mW output power.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
EXAMPLE 1
FIG. 1 shows the distributed feedback semiconductor laser array device of this invention, which can be fabricated as follows: On a p + -GaAs substrate 1, an n-GaAs current blocking layer 2 having a thickness of 1 μm is grown by a crystal growth technique such as liquid phase epitaxy, vapor phase epitaxy, metal organic-chemcial vapor deposition, molecular beam epitaxy or the like. Then, a plurality of V-channels 20 having a depth of 1.1 μm and a width of approximately 4.0 μm are formed in a parallel manner with the center-to-center spacing of 5.0 μm at the current blocking layer side by photolithography and an etching technique in such a manner that they reach the substrate 1. Then, on the current blocking layer 2 including these V-channels 20, and p-A1 x Ga 1-x As cladding layer 3, a p-A1 y Ga 1-y As optical guiding layer 4, an n- or p-A1 z Ga 1-z As active layer 5 and an n-A1 y Ga 1-y As optical guiding layer 6 are successively grown by liquid phase epitaxy, vapor phase epitaxy, metal organic-chemical vapor deposition, molecular beam epitaxy or the like (wherein x>y>z≧0). On the whole surface of the n- optical guiding layer 6, a grating 30 having the center-to-center spacing of approximately 325 nm and a depth of 0.1 μm is formed at right angles to the V-channels 20 by photolithography, using a photographic exposure with an optical interference system, and an etching technique. Then, on the optical guiding layer 6 having the grating 30, an n-A1 x Ga 1-x As cladding layer 7 and an n + -GaAs contact layer 8 are grown by metal organic-chemical vapor deposition, molecular beam epitaxy or the like. Ohmic contacts 9 and 10 are then formed on the upper face of the grown layers and the back face of the substrate 1 of the resulting wafer, respectively, followed by the formation of rough faces 40 by an etching technique at the sides which are parallel to the V-channels 20 and the formation of facets 41 by cleavage at the other sides which are perpendicular to the V-channels 20, resulting in a semiconductor laser array device.
The rough faces 40 are not vertical to the substrate 1 although the cleavage facets 41 are vertical to the substrate 1. The rough faces 40 are not formed into a cleavage facet in order to suppress the effect of the Fabry-Perot oscillation mode on the distributed feedback mode with which this invention is concerned. In order to attain the same purpose as mentioned above, a dielectric film is formed on each of the cleavage facets 41 by a sputtering technique using a high frequency, thereby minimizing the reflection index thereof.
In general, distributed feedback laser devices which have the structure of a single-striped channel hardly exhibit the dependence of oscillation wavelength on temperature (or electric current) as compared with Fabry-Perot laser devices. In the same manner, the distributed feedback laser array device of this example hardly exhibits the dependence of oscillation wavelength on temperature (or electric current) as compared with a conventional Fabry-Perot laser array device. This is because even when a difference in temperature between the center striped channel and the outer striped channels arises, the oscillation wavelengths at the striped channels of the distributed feedback laser array device of this example do not give rise to differences therebetween as compared with those at the striped channels of the conventional Fabry-Perot laser array device, so that the distributed feedback laser array device is liable to attain laser oscillation with a 0°-phase shift between the adjacent striped channels. Therefore, the distributed feedback laser array device of this invention can maintain a synchronous state of laser lights up to a high electric current level (i.e., high output power) as compared with the conventional laser array device when the amount of injection electric current is increased.
It was observed that the distributed feedback laser array device having three striped channels of this example could attain laser oscillation with a 0°-phase shift between the adjacent channels up to an approximately 80 mW output power. EXAMPLE 2
FIGS. 2(a) and 2(b) show another semiconductor laser array device having an internal reflection structure, which can be fabricated as follows: On a p + -GaAs substrate 101, an n-GaAs current blocking layer 102 having a thickness of approximately 1.0 μm is grown by liquid phase epitaxy, metal organic-chemical vapor deposition or the like. Then, a plurality of V-channels 120 having a depth of approximately 1.1 μm and a width of 3.5 μm are formed in a parallel manner with the center-to-center spacing of 5.0 μm at the current blocking layer side by photolithography and an etching technique in such a manner that they reach the substrate 101. As shown in FIG. 2(a), each of the V-channels 120 has an enlarged portion 120a with a length of 10 μm and a width of 4.5 μm in the center thereof in the direction which is perpendicular to the V-channels. On the current blocking layer 102 including the V-channels 120, as shown in FIG. 2(b), a p-A1 u Ga 1-u As cladding layer 103, a p- or n-A1 v Ga 1-v As active layer 104, an n-Al u Ga 1-u As cladding layer 105 and an n + -GaAs contact layer 106 are successively grown by liquid phase epitaxy. By the selection of the growth rate for the p-cladding layer 103, the active layer 104 can be formed into a plane shape. Then, ohmic contacts 107 and 108 are formed on the back face of the substrate 101 and the upper face of the grown layers, respectively. The facets 141, which are at right angles to the V-channels 120, are formed by cleavage to function as laser oscillation faces. The cleavage position must be selected in such a manner that the enlarged portions 120a of the V-channels 120 are not exposed from the facets 141.
The resulting laser array device, in which the individual V-channels 120 function as a single lasing striped channel, has a difference in equivalent refractive index at the interface between each of the striped V-channels 120 and the enlarged portion 120a thereof, causing an internal reflection therein. Thus, the individual V-channels function in the same manner as in a laser device with internal reflection, so that the oscillation wavelength hardly varies with a variation in temperature (or electric current), that is, the laser array device with internal reflection of this example has a structure which allows the attainment of laser oscillation with a 0°-phase shift between the adjacent channels up to a high electric current level (i.e., high output power).
A semiconductor laser array device having a distributed Bragg reflection structure can also attain laser oscillation with a 0°-phase shift between the adjacent channels up to high output power as in Example 1. Such a structure is illustrated in FIG. 1A and may be fabricated in accordance with the description of Example 1 with modifications known to those skilled in the art. Substrate 1a, current blocking layer 2a, V-channels 20a, cladding layer 3a, optical guiding layer 4a, active layer 5a, optical guiding layer 6a, cladding layer 7a, and contact layer 8a are formed exactly as described in Example 1. Portions of contact layer 8a, cladding layer 7a, optical guiding layer 6a, and active layer 5a in region 51 are then removed using conventional photolithography and etching techniques so as to expose optical guiding layer 4a. Periodic grating 30a is then formed on optical guiding layer 4a in the same manner as in Example 1. Ohmic contact 9a is formed over contact layer 8a in region 50 in the same manner as in Example 1. Ohmic contact 10a as well as facets 40a and 41a are also formed in the same manner as in Example 1.
Various modifications of the semiconductor laser array device of this invention include:
(i) Devices which are designed to provide a structure having a different polarity from the polarity of each of the substrate and the grown layers in the above-mentioned examples.
(ii) Devices which are designed using other materials achieving laser oscillation.
(iii) Devices which are designed by the application of semiconductor laser structure to the individual striped-channels of laser array devices.
(iv) Devices which are designed using other structures which minimize the dependence of wavelength in the oscillation longitudinal mode on temperature.
It is understood that various other modifications will be apparent to and can be readily made by those skilled in the art without departing from the scope and spirit of this invention. Accordingly, it is not intended that the scope of the claims appended hereto be limited to the description as set forth herein, but rather that the claims be construed as encompassing all the features of patentable novelty which reside in the present invention, including all features which would be treated as equivalents thereof by those skilled in the art to which this invention pertains. | A semiconductor laser array device comprising a structure for minimizing the dependence of the longitudinal mode of laser oscillation upon the driving electric current, thereby facilitating laser light oscillation at a high output power with a zero degrees phase shift between adjacent lasing elements. | 7 |
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an encoding and decoding method and device for compression encoding, transmitting and decoding of information of an image signal or audio signal.
2. Description of the Prior Art
In the field of image or voice communication, there has so far been performed compression of signals or highly efficient encoding of data in order to efficiently utilize the limited line capacity. One practical example is an encoding and decoding device for used in TV conference or TV telephone.
"A Fractal Based Approach To Image Compression", ICASSP, 86, 11A.3 is known to the present inventors as a reference closely related to the present invention. This reference is to compress image data using the fractal concept. The basic concept is in that "yard stick" of certain fixed length is used as a unit to cover a signal, and a horizontal distance of the cross point at which "yard stick" intersects the signal, i.e., sampling interval and a positive or negative sign bit respectively indicative of increase or reduction in an amplitude value are both transmitted for restoration of the signal at the decoding side. The practically implementing method employs "trigger function" in place of "yard stick", the trigger function being compared with the signal to determine a sampling interval. This makes the sampling interval wider for a signal including many flat parts, so that the signal may be compressed to a large extent.
However, because "trigger function" is a unique function for all of successive data samples, the above method cannot follow a multi-value graded image including steeply changing parts, resulting in a problem that the image may be blurry in its edge. Another problem is in that since representative values used in the decoding step are given by those threshold values which were used in the encoding step, the decoded values are always less than the amplitude values of the original signal, and hence the mean square error is increased. It is to be noted that the above reference teaches only the method, and does not propose a practical device.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a method and device for encoding and decoding signals, which are fit for human visual and auditory characteristics, and which are adapted to reduce the information content necessary for transmitting and storing an image or audio signal.
To achieve the above object, the present invention resides in a method of encoding and decoding image and audio signals, any of the signals being subjected to sampling and having a multiplicity of sampling points each represented by a quantized amplitude value.
An encoding step comprises the steps of:
transmitting an amplitude value of a given sampling point as an initial value;
subtracting the initial value from each of amplitude values of n sampling points (where n is a predetermined integer) to calculate n difference values therebetween, and calculating positive or negative signs, which respectively indicate varying directions of the amplitudes imposed by the difference values with respect to the initial value and absolute values of the difference values;
previously preparing a quantization table which has threshold values and representative values expressed in terms of amplitude values, defines an ordered set of n quantization scales (where n is a predetermined integer) each comprising at least one threshold value and a representative value, and also defines index values different from one another for all the representative values of said n quantization scales;
comparing a series of n difference absolute values with a series of n quantization scales included in the quantization table sequentially from the sampling point adjacent to the initial value until the maximum n-th sampling point, and selecting a representative value of the most suitable quantization scale;
transmitting the index value of the selected representative value of the quantization scale and the positive or negative sign; and
repeating the foregoing steps with the sum of the selected representative value of the quantization scale and the current initial value being set as a subsequent initial value.
A decoding step comprises the steps of:
receiving the amplitude value of the transmitted sampling point as an initial value;
previously preparing the same quantization table as used during the encoding step;
determining the number m and the representative value corresponding to the received index value and the sign by making use of the quantization table;
interpolating the amplitude value of each of (m-1) sampling points between the initial value and the sum of the initial value and the representative value of m-th sampling point; and
repeating the foregoing steps with the sum of the initial value and the representative value of m-th sampling point being set as a subsequent initial value.
The foregoing method allows sampling to be finely carried out in the steeply changing part, but roughly carried out in the moderately changing part, so that image and audio signals can be encoded with high efficiency in better fitting for human visual and auditory characteristics.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of one embodiment of an encoding device for encoding signals according to the method of the present invention;
FIG. 2 is more detailed block diagram of FIG. 1;
FIG. 3 is one example of quantization table;
FIG. 4 is a block diagram of one embodiment of a decoding device for decoding the encoded data according to the method of the present invention;
FIG. 5 is a more detailed block diagram of FIG. 4;
FIG. 6 is a block diagram of another embodiment of an encoding device for encoding signals according to the method of the present invention; and
FIG. 7 is a more detailed block diagram of FIG. 6.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
One embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a block diagram of one embodiment of an encoding device according to the present invention. The encoding device of FIG. 1 comprises an input terminal 11, an initial value updating circuit 12, a subtraction circuit 13, an absolute value circuit 14, a quantization table 15, a comparison circuit 16, a transmitter 17, and an output terminal 18. Applied to the input terminal 11 is a series of image or audio data after being subjected to sampling and quantizing. First, an initial value S i is held in the initial value updating circuit 12. The initial value S i is also supplied to the transmitter 17. The subsequent data S i+1 and the output S i of the initial value updating circuit 12 are supplied to a subtraction circuit 13 where both ΔS1=S i+1 -S i and the sign F1=sign(ΔS1) are calculated. The output ΔS1 of the subtraction circuit 13 is then supplied to the absolute value circuit 14, while F1 is held therein until receiving of an indication from the comparision circuit 16. The absolute value circuit 14 calculates an absolute value | ΔS1| of ΔS1 and sends it to the comparison circuit 16. The quantization table 15 is a table having an ordered set of n quantization scales (where n is a positive integer). Each quantization scale has at least one quantization level, and each quantization level has a single representative value Rk. The quantization levels are partitioned from each other by respective threshold values. The quantization table 15 outputs the threshold value of first quantization scale and sends it to the comparison circuit 16. The comparison circuit 16 compares the threshold value of first quantization scale with the absolute value |ΔS1| to check to which quantization level the absolute value |ΔS1| belongs. If |ΔS1| is found within the threshold value of any quantization level, this means the presence of a matching quantization level. In this case, the comparison circuit 16 supplies the index of quantization level and the sign F1 delivered from the subtraction circuit 13 to the transmitter 17. The comparison circuit 16 also resets the quantization table 15. Further, the comparison circuit 16 sends the representative value Rk of the selected index to the initial value updating circuit 12. The initial value updating circuit 12 holds the sum of the initial value S i originally held therein and the representative value Rk as a new initial value. The above process is effected when the matching quantization level is present.
If the absolute value |ΔS1| is less than the minimum threshold value of first quantization scale, this means the absence of a matching quantization level. In this case, the subsequent data S i+2 is supplied to the subtraction circuit 13 where ΔS2=S i+2 -S i is calculated. ΔS2 is processed in a like manner to ΔS1. More specifically, the quantization table 15 outputs the threshold value of second quantization scale, which is then compared with |ΔS2| in the comparison circuit 16. If a matching quantization level is found, the comparison circuit 16 supplies both the index of that quantization level and the sign delivered from the subtraction circuit 13. If not, the subsequent sampling point S i+3 is supplied to the subtraction circuit 13 where ΔS3=S i+3 -S i is calculated. Thereafter, the similar process will be repeated until calculation of ΔSn=S i+n -S i at maximum. The transmitter 17 outputs a series of indices and signs from the output terminal 18.
FIG. 2 is a more detailed block diagram of FIG. 1. The initial value updating circuit 12 comprises a selector 21, register 22 and full adder 23. The selector 21 makes switching action to select either the first initial value or the updated initial value. The initial value means, for example, an amplitude value of first pixel on one horizontal scanning line in connection with image. The register 22 holds the initial value selected by the selector 21. The full adder 23 adds the current initial value held in the register 21 and the representative value Rk of the index selected by the comparison circuit 16, and then outputs the sum therefrom.
The subtraction circuit 13 comprises a two's complementer 24 and a full adder 25. The two's complementer 24 operates to determine the subtractive value of the data applied thereto for implementing the subtraction in the full adder 25. The full adder 25 adds the initial value held in the register 22 and the output of the two's complementer 24 to thereby obtain the resulting difference value ΔS1. At the same time, the positive or negative sign F1 is also obtained. The absolute value circuit 14 functions to determine |ΔS1|.
The quantization table 15 comprises a ROM (Read Only Memory) 27 for storing threshold values and a counter 28. The counter 28 is reset by the comparison circuit 16 upon updating of the initial value, and then counted up by sampling clocks applied thereto. FIG. 3 shows the relationship among the index, the sample number, the range of threshold values, and the representative value. The ROM 27 is designated to receive the output of the counter 28, i.e., the sample number, as an address input and responsively output the lowest value of each range of threshold values. Assuming for the sample S1 to be input, for example, the counter 28 outputs 1 as the sample number and supplies it to the ROM 27 as an address for accessing. The ROM 27 outputs three values, i.e., 16, 27 and 42 as seen from FIG. 3, and supplies the value 16 to a comparator 29, the value 27 to a comparator 30, and the value 42 to a comparator 31, respectively, the comparators 29-31 being constituent components of the comparison circuit 16. The output of the absolute value circuit 14 is supplied to each of the comparators 29, 30 and 31, and the resulting output values are used for selection of a matching quantization level. More specificatlly, when the output of the absolute value circuit 14 is equal to or greater than the output of the ROM 27, one or more of the corresponding comparators 29, 30 and 31 issue a logical "true" output. With the absolute value circuit 14 outputting 16- 26, only the comparator 29 issues a "true" output. With the absolute value circuit 14 outputting 27-41, the comparators 29 and 30 issue each a "true" output. With the absolute value circuit 14 outputting 42 or more, all of the comparators 29, 30 and 31 issue "true" outputs. Assuming that the output of the absolute value circuit 14 is equal to 20, for example, only the comparator 29 issues a "true" output, while the remaining comparators issue "false" outputs.
A ROM 32 is designed to output an index, a representative value, and a reset signal for the counter 28 by making use of the true/false outputs of the comparators 29, 30, 31 and the counter value of the counter 28 as respective address inputs. In case of the foregoing example, since the counter 28 issues the output of 1 and the range of threshold values is 16-26, i.e., the comparator 29 issues a "true" output and the comparators 30, 31 issuee "false" outputs, the ROM 32 delivers the index 1 and the representative value 21 as shown in FIG. 3. The ROM 32 outputs a reset signal and supplies it to the counter 28, when at least one of the comparators 29, 30 and 31 issues a "true" output. Therefore, the counter 28 is reset in the above case. Supposing that the output of the absolute value circuit 14 is equal to or less than 15 in the foregoing example, all of the comparators 29, 30 and 31 issue "false" outputs. In this case, there exists no matching quantization level for the first sample, so the process proceeds to comparison of the subsequent sample. Thus, the initial value updating circuit 12, subtraction circuit 13 and absolute value circuit 14 operate in a like manner to the above, and the absolute value circuit 14 outputs |ΔS2|, The counter 28 is counted up and issues the output of 2. Accordingly, the ROM 27 now outputs 8 and 17 to the comparators 29 and 30 in the example of using the table of FIG. 3, the respectively. Thereafter, the similar process will be repeated to find a matching quantization level for each of a successive sample numbers. If not found, it proceeds to processing of the subsequent sample. In accordance with the exemplary table of FIG. 3, when the process finally reaches the sample number 5, the ROM 32 outputs the index 7 and the representative value 0 irrespective of the output value of the absolute value circuit 14. The index in the output of the ROM 32 is supplied to a register 33 constituting the transmitter 17, and then delivered from the output terminal 18 together with the sign supplied from the full adder 25. The representative value in the output of the ROM 32 is supplied to the full adder 23.
While the present invention has been described with reference to the quantization table shown in FIG. 3 by way of example, the quantization table is not limited to the illustrated one. Thus, the number of indices, the magnitude of sample numbers, the ranges of threshold values, and representative values may have optional values so long as they will not be contradictory to each other. Therefore, the number of comparators to be included in the comparison circuit 16 depends on the configuration of each quantization table.
With the operation as mentioned above, the part of signal which has an amplitude value changing steeply is quantized at the first sample, but the sample number proceeds in order of 2, 3, 4 and 5 as the signal changes more moderately. As a result, the original sampling interval is widened and hence the amount of data is reduced. Generally speaking, since the natural image or audio signal has many moderately changing parts as a whole, the present method makes it possible to increase the compression gate.
FIG. 4 shows one embodiment of a decoding device according to the present invention. The decoding device of FIG. 4 comprises an input terminal 41, a receiver 42, a quantization table 43, an interpolation circuit 44, an arithmetic circuit 45, an initial value updating circuit 46, and an output terminal 47. A series of encoded data is inputted to the input terminal 41 and then supplied to the receiver 42. The receiver 42 separates the initial value S i from the index k and the sign F. The initial value is supplied to the initial value updating circuit 46, and the index and the sign are supplied to the quantization table 43. The quantization table 43 has the same quantization table as used in the encoding device, and outputs the sample number and the representative value upon receiving the index applied thereto. The representative value is added with the positive or negative sign and then supplied to the interpolation circuit 44. The interpolation circuit 44 calculates one or more interpolation values from the sample number and the representative value. The case of sample number 1 does not require interpolation, but the case of sample number 2 or more requires interpolation. The interpolated data is in the form of series of difference values and supplied to the arithmetic circuit 45. In the arithmetic circuit 45, the initial value held in the initial value updating circuit 46 and the series of difference values are sequentially added to give a series of decoded signals, which is then delivered from the output terminal 47. The final value in the data series from the arithmetic circuit 45 is supplied to the initial value updating circuit 46 for updating the previous initial value.
FIG. 5 is a more detailed block diagram of FIG. 4. The receiver 42 comprises a register 51. The register 51 separates the initial value out of the data series encoded by encoding device, followed by supplying it to the initial value updating circuit 46, while it supplies the index and the sign to the quantization table 43.
The quantization table 43 comprises a ROM 52. The ROM 52 outputs the sample number and the representative value using the index and the sign as address inputs. If the encoding device employs the quantization table shown in FIG. 3, the decoding device has also to employ the same quantization table as shown in FIG. 3. The representative value output from the ROM 52 is given by the representative value shown in FIG. 3 added with the positive or negative sign.
The interpolation circuit 44 comprises a down counter 53 and a ROM 54. The sample number outputted from the ROM 52 is loaded into the down counter 53. The representative value delivered from the ROM 54 and the output of the down counter 53 are supplied to a ROM 54 as addresses for accessing. Responsively, the ROM 54 outputs the interpolation value which is previously calculated and stored herein.
The arithmetic circuit 45 comprises a full adder 55. The full adder 55 adds the output of the ROM 54 and the initial value stored in a register 57 of the initial value updating circuit 46, and then supplies the resulting sum to the output terminal 47. A selector 56 of the initial value updating circuit 46 makes switching action to selects either the initial value supplied from the register 51 or the final output value from the full adder 55. Only upon the register 51 detecting the initial value, the selector 56 is switched to the side of the register 51. The output of the selector 56 is supplied to the register 57. The new initial value is stored in the register 57 and, at the same time, the register 51 supplies the subsequent index and sign to the ROM 52 for repeating the above process.
While both the index and the sign were employed as input addresses for the ROM storing the quantization table in the foregoing embodiment, it may be configured that only the index is employed as an input address for the ROM, and the sign is directly added to the output of the ROM for providing the representative value with the positive or negative sign. Also, while the interpolation circuit was consisted of the down counter and the ROM, it is not limited to such configuration and may comprise, for example, an up counter, a comparator and a ROM.
FIG. 6 is a block diagram of another embodiment of an encoding device according to the present invention. The encoding device of FIG. 6 comprises an input terminal 11, an initial value updating circuit 12, a subtraction circuit 13, an absolute value circuit 14, three quantization tables 61, 62 and 63, a comparision circuit 16, a transmitter 66, a switching circuit 64, a monitor circuit 65, and an output terminal 18. Applied to the input terminal 11 is a series of image or audio data after being subjected to sampling and quantizing. First, an initial value Si is held in the initial value updating circuit 12. The initial value S i is also supplied to the transmitter 17. The subsequent data S i+1 and the output S i of the initial value updating circuit 12 are supplied to a subtraction circuit 13 where both ΔS1=S i+1 -S i and the sign F1=sign (ΔS1) are calculated. Then, the output ΔS1 of the subtraction circuit 13 is supplied to the absolute value circuit 14, and F1 is supplied to the transmitter 66. The absolute value circuit 14 calculates an absolute value |ΔS1| of ΔS1 and sends it to the comparison circuit 16. On the other hand, the quantization tables 61, 62 and 63 output the respective threshold values of first quantization scales and supply them to the switching circuit 64. The switching circuit 64 selects and outputs a proper input dependent on the output of the monitor circuit 65. The comparison circuit 16 compares the threshold value of the selected quantization table with the absolute value |ΔS1| to check to which quantization level the absolute value |S1| belongs. If a matching quantization level is found, the comparison circuit 16 supplies the index of quantization level to the transmitter 66. Concurrently, the sign F1 is supplied from the subtraction circuit 13 to the transmitter 66. Further, the representative value Rk of the selected index is supplied to the initial value updating circuit 12. The initial value updating circuit 12 updates the sum of the initial value S i originally held therein and the representative value Rk as a new initial value.
If the absolute value |ΔS1| is less than the minimum threshold value of quantization scale for the first sample, the matching quantization level cannot be found. Thus, the subsequent data S i+2 is supplied to the subtraction circuit 13 where ΔS2=S i+2 -S i is calculated. ΔS2 is processed in a like manner to ΔS1 through the above-mentioned steps. The transmitter 66 supplies respective values of input rate and output rate to the monitor circuit 65. The monitor circuit 65 calculates the integrated value of differences between the input rate and the output rate, and converts it to a switching signal which is delivered to the switching circuit 64.
This embodiment has a function to maintain constant the data output rate of the encoding device. The quantization tables 61, 62 and 63 have their quantization scales made up such that when those three quantization tables are used for the same input signal, the first quantization table 61 produces the largest amount of decoded data, the third quantization table 63 produces the least amount of decoded data, and the second quantization table 62 produces the intermediate amount of decoded data. Provided that the input data rate is higher than the output data rate owing to the complicated input signal, the transmission will soon be crashed. To avoid such crash, the monitor circuit 65 integrates the difference between the input rate and the output rate at all time, and converts the integrated value to the switching signal. It is assumed that the first quantization table 61 is selected by the switching circuit 64 at the first stage. When the input rate exceeds the output rate in this stage, the switching circuit 64 outputs such a selection signal as by which the second quantization table 62 is selected. When the input rate still yet exceeds the output rate, another selection signal is output to select the third quantization table 63. To the contrary, when the input rate is below the output rate, the switching circuit 64 is controlled to sequentially select the third quantization table 63, second quantization table 62 and first quantization table 61 in this order. This prevents the encoding device from coming into crash, while keeping the output rate kept at constant.
FIG. 7 is a more detailed block diagram of the quantization tables 61, 62 and 63, switching circuit 64, monitor circuit 65, and transmitter 66 of FIG. 6. The first quantization table 61 comprises a ROM 71 and a counter 72. The second quantization table 62 comprises a ROM 73, and the third quantization table 63 comprises a ROM 74. The counter 72 is counted up by signal sampling clocks, and reset by the comparison circuit 16 when it detects a matching quantization level. The ROM's 71, 73 and 74 are operated synchronously by virtue of the counter 72. The switching circuit 64 makes switching action to select any one of the threshold value outputs from the ROM's 71, 73 and 74, and the delivers the selected one to the comparison circuit 16.
The transmitter 66 comprises a RAM (Random Access Memory) 75, an arbitration circuit 76, a write address counter 77, and a read address counter 78. The input data such as index is written into the RAM 75. At this time, write addresses are produced by the write address counter 77 and applied to the RAM 75 via the arbitration circuit 76. Meanwhile, read addresses are produced by the read address counter 78 and applied to the RAM 75 via the arbitration circuit 76. Since the transmitter 66 is set to have the constant output rate, the arbitration circuit 76 passes the read addresses with higher priority, while keeping the write addresses queued.
The monitor circuit 65 comprises a subtractor 79, an accumulator 80 and a converter 81. The subtractor 79 subtracts the count value of the read address counter 78 from the count value of the write address counter 77, and then supplies the resulting difference to the accumulator 80. The accumulator 80 accumulates the differences about a predetermined value. The increased input rate advances the write address, which reduces the output value of the subtractor 79 so that the output value of the accumulator 80 becomes small. The converter 81 produces switching signals by which the switching circuit 64 selects the ROM 74 when the accumulator 80 has a small value, it selects the ROM 73 when the accumulator 80 has a value exceeding a first predetermined threshold value, and it selects the ROM 71 when the accumulator 80 has a value exceeding a second predetermined threshold value. This implements to effect such control as reducing the amount of index and sign data produced when the data input to the RAM 75 is increased, but increasing the amount of index and sign data produced when the data input to the RAM 75 is reduced.
The monitor circuit and the transmitter in this embodiment are not limited to the illustrated configurations. For example, the RAM 75 in the transmitter 66 may comprise a FIFO (First In First Out) memory. | A method of encoding and decoding image and/or audio signals includes an encoding step comprising previously preparing a quantization table which has pairs of a sampling interval and a quantized difference value, calculating a difference value between a given initial value and a sampling point succeeding to the initial value, comparing the calculated difference value with the quantization table, and searching the most matching quantization level. The search is started from the sampling point immediately succeeding to the initial value and then stopped upon finding of the matching quantization level. The index of that matching quantization level is transmitted. The decoding step comprises preparing the same quanitization table as used in the encoding step, determining the sampling interval and the quantized difference value based on the index received, and adding the quantized difference value to the initial value to obtain a decoded value. In case there are present two or more sampling intervals, the corresponding samples are interporated. As a result, the sampling interval is prolonged in the flat parts of signal and shortened in the steeply changing parts, thereby providing compression fit for human visual and auditory characteristics. | 7 |
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of PCT Application No. PCT/CN2015/085518 filed on Jul. 30, 2015, which claims priority to Chinese Application No. 201410370007.2 filed on Jul. 30, 2014, the contents of which are hereby incorporated by reference as if recited in their entirety.
FIELD OF THE INVENTION
The invention relates to the field of petroleum drilling engineering, and in particular, to a wellbore pressure correction method.
BACKGROUND OF THE INVENTION
During a drilling process of petroleum and natural gas, calculation and control for the wellbore pressure become very important in order to avoid complicated accidents such as leakage, kick, hole instability, sticking, and/or the like. Currently, a gas-liquid two-phase flow theory is one of theoretical bases of gas-liquid two-phase flow simulated calculation for the wellbore, which establishes a gas-liquid two-phase continuity equation, a momentum equation by dividing different flow patterns, to simulate a flow state. However, differences between different calculation methods are relatively large and thus the precision is hard to meet requirements for calculation of dynamic pressure of a delicate controlled pressure wellbore for pressure sensitive formation.
To avoid the occurrence of the accidents, the drilling method for managed pressure drilling (MPD) has been widely used in the field of drilling petroleum and natural gas. However, there is no solution for a real-time control of the MPD pressure yet to satisfy the requirements for fast and accurate calculation of the dynamic pressure of the wellbore for petroleum and natural gas.
SUMMARY OF THE INVENTION
An object of the invention is to provide a wellbore pressure correction method to more fastly and accurately calculate the pressure of wellbore in real-time.
To achieve the abovementioned purpose, an embodiment of the invention provides a method for wellbore pressure correction, comprising: measuring a bottom hole pressure using a downhole pressure measurement-while-drilling tool; calculating a predicted bottom hole pressure; and correcting a wellbore pressure using the measured bottom hole pressure and the predicted bottom hole pressure to achieve MPD.
Preferably, the predicted bottom hole pressure is calculated according to the following equation: P b (t)=P h (t)+P f (t)+P w (t), where P b (t) is the bottom hole pressure at time t, P h (t) is a hydrostatic column pressure at time t, P f (t) is an annular pressure lost at time t, and P w (t) is a wellhead back pressure at time t.
Preferably, P h (t)=ρ mix (t)gH(t), where
ρ mix ( t ) = m g ( t ) + m l ( t ) V ( t ) ,
m g (t) is an annular gas mass for the wellbore at time t, m l (t) is an annulus liquid mass at time t, V(t) is a volume of annular at time t, g is a gravitational acceleration, and H(t) is an actual depth-drilled at time t.
Preferably,
P f ( t ) = f ρ mix ( t ) H ( t ) v mix 2 ( t ) 2 D a ,
where v mix ( t ) = Q mix ( t ) A ,
Q mix ( t )
is a measured value by a mass flowmeter at time t, A is an annular flow area, D a is a hydraulic diameter, and f is a coefficient of friction resistance.
Preferably, P w (t)=P w0 −ΔP h (t)+ΔP safe where ΔP safe is an additional safety pressure value, P w0 is the wellhead back pressure in the absence of overflow,
Δ P h ( t ) = - ( ρ i - ρ g ) V g t V gH ,
ρ t is an annulus liquid density, ρ g is a gas density on the condition of an average pressure being [(P b −P w )/2, (P b +P w )/2], V is a volume of annular in the presence of overflow, H is a well depth in the presence of overflow, V g (t)=∫ 0 t q g (t) dt, q g (t) is an overflow velocity at time t, P b is a bottom hole pressure preset at the time of designing the MPD, P w is a pressure value in a safe range of the wellhead back pressure for the MPD, H is a current well depth, V is the volume of annular corresponding to the current well depth.
Preferably, correcting the wellbore pressure using the measured bottom hole pressure and the predicted bottom hole pressure to achieve MPD comprises checking an annular pressure lost according to the following equation to achieve MPD:
P f ( t ) new = f ′ ρ mix ( t ) H ( t ) v mix 2 ( t ) 2 D a ; where f ′ = P f ′ ( t ) P f ( t ) · f ,
P f ′ ( t ) = P f ( t ) - Δ P ( t ) ,
Δ P ( t ) = P b ( t ) - P pwd ( t ) ,
P f ( t ) new
is a checked annular pressure lost at time t, and P pwd (t) is the measured bottom hole pressure at time t.
Preferably, correcting the wellbore pressure using the measured bottom hole pressure and the predicted bottom hole pressure to achieve MPD comprises checking the wellhead back pressure according to the following equation to achieve MPD: P′ w (t)=P′ b (t)−P h (t)−P f (t); where P′ w (t) is a checked wellhead back pressure at time t,
α
=
P
pwd
(
t
)
P
b
(
t
)
,
P
b
′
(
t
)
=
α
P
b
(
t
)
.
Preferably, the method further comprises controlling a choke valve aperture such that the annular pressure lost reaches the checked annular pressure lost or the wellhead back pressure reaches the checked wellhead back pressure.
One or more embodiments of the invention can overcome the defect existing in the prior art, that is, the difference between a downhole pressure calculated from a wellbore pressure calculation processing method and the actual downhole pressure is relatively large. One or more embodiments of the invention can also be able to more quickly and accurately calculate the wellbore pressure in real time to achieve accurate calculation and real-time correction and control of dynamic wellbore pressure on a narrow density window formation, and thereby achieve a good control of bottom hole pressure and guarantee safe and quick drilling.
Other features and advantages of the present invention will be illustrated further in detail while explaining embodiments hereafter.
BRIEF DESCRIPTION OF DRAWINGS
The accompanying drawings are provided here to facilitate further understanding of the present invention, and constitute a part of this specification, they are used in conjunction with the following embodiments to explain the present invention, but shall not be construed as constituting any limitation to the present invention, wherein:
FIG. 1 is a schematic diagram of the wellbore pressure distribution;
FIG. 2 is a flow diagram of the wellbore dynamic pressure correction provided in the invention.
DESCRIPTION OF THE SYMBOLS
10 Mud pump
12 Choke valve
14 Mass flowmeter
DETAILED DESCRIPTION OF THE EMBODIMENTS
Some embodiments of the present invention will be described in detail hereafter. It is appreciated that these embodiments are used to explain and illustrate the present invention, but by no means to limit the present invention.
In embodiments of the invention, the correction of the wellbore pressure may be based on the basic principles of the mass and pressure conservation and the wellbore gas-liquid two-phase flow theory.
FIG. 1 shows a schematic diagram of a distribution of wellbore pressure. As shown in FIG. 1 , a mud pump 10 pumps drilling circulating liquid into a well; annular circulating liquid will enter into a mud tank through a choke valve 12 and a mass flowmeter 14 . Considering the formation is of water or liquid breakthrough, the density of which differs little from that of the drilling circulating liquid, and thus a change in the wellbore pressure is relatively slow, thereby the MPD is relatively easy to be done. Therefore, only the situation where the formation is outgassed is considered rather than the situation of water or fluid-breakthrough, while calculating the wellbore pressure for the MPD.
During the process of correction of the wellbore pressure, different correction approaches can apply for different situations. Embodiments of the invention primarily employ two correction approaches: one is related to checking the annular pressure lost and the other is related to checking the wellhead back pressure. The following will describe in detail how to perform the wellbore pressure correction according to the basic principles of mass and pressure conversation.
According to the mass conversation law, in a case that there is a stable drilling liquid circulating system, with no fluid input and fluid output and no additional energy exchange, the mass is considered in balance. In a case that the mass is balanced, it necessarily means energy balance, i.e., pressure balance. In a case that the mass is unbalanced, energy will be unbalanced, so that the pressure will not be in balance. According to the energy conservation law, a total drilling liquid volume=a drilling tool water hole volume+a wellbore volume of annular+a mud tank volume=a constant. The drilling tool can be considered as remaining unchanged in a certain time period, so the drilling tool water hole volume remains relatively unchanged; therefore, it can be considered that: a wellbore volume of annular+a mud tank volume=a constant.
Without considering fluid's acceleration motion, according to the pressure conservation principle, the bottom hole pressure is given by:
P b ( t )= P h ( t )+ P f ( t )+ P w ( t ) (1)
In the equation:
P b (t): a bottom hole pressure at time t;
P h (T): a hydrostatic column pressure at time t;
P f (t): an annular pressure lost at time t;
P w (t): a wellhead back pressure at time t (i.e, an upstream pressure of a choke valve).
Notably, since the gas in the formation is injected into the bottom and returns upward along an annulus space, gas compressibility needs to be considered. A change in the hydrostatic column pressure is also due to the change in density of a mixture. P b (t) can be calculated and predicted using a model, P w (t) can be measured in real time by an apparatus such as a pressure sensor.
The hydrostatic column pressure and the annular pressure lost are calculated as follows:
P
h
(
t
)
=
ρ
mix
(
t
)
gH
(
t
)
(
2
)
ρ
mix
(
t
)
=
m
g
(
t
)
+
m
l
(
t
)
V
(
t
)
(
3
)
In the above equations, ρ mix (t) is the density of the mixing liquid within the wellbore at time t; H(t) is an actual depth-drilled at time t; m g (t) is an annular gas mass for the wellbore at time t; m l (t) is an annulus liquid mass at time t; V(t) is a volume of annular at time t, which can be calculated based on a wellbore structure and a diameter of an open hole section and a volume of a well-entering part of a drilling string.
m g (t)=ρ g V g , where ρ g is the gas density if an average pressure is [(P b −P w )/2, (P b +P w )/2]. At this time, P b is a bottom hole pressure preset when designing the MPD, P w is required to be within a safe range of the wellhead back pressure for the MPD. For example, it is specified as [0, 5] MPa. ρ g can be considered as a constant.
V g (t) is a downhole overflow amount, which can be calculated according to the following equation:
V g ( t )=∫ 0 t q g ( t ) dt (4)
q g (t) is an overflow velocity at time t, which can be obtained by measuring a liquid level of the mud tank.
m l =ρ l ( V ( t )− V g ( t )) (5)
When special working conditions such as overflow or leakage occur, drilling will not continue and it is required the processing for the special working conditions is complete at the current depth before continuing drilling; at this time, V(t) and H(t) are respectively a volume of annular V and a well depth H corresponding to the current well depth, where ρ l is the density of the drilling liquid. The time t is derived by the equation (2):
dp
h
(
t
)
dt
=
-
(
ρ
1
-
ρ
g
)
q
g
(
t
)
V
gH
(
6
)
The annular pressure lost is calculated by the following equations:
1
f
≈
-
1.8
log
10
[
6.9
Re
+
(
ε
/
D
a
3.7
)
1.11
]
(
7
)
v
mix
(
t
)
=
Q
mix
(
t
)
A
(
8
)
Q mix (t): a measured value by the mass flowmeter at time t (volume flow)
A: an annular flow area;
D a : hydraulic diameter,
D
a
=
D
o
-
D
i
2
f: a coefficient of friction resistance, which can be calculated by the following equations:
1
f
≈
-
1.8
log
10
[
6.9
Re
+
(
ε
/
D
a
3.7
)
1.11
]
(
9
)
ε/D a is a relative roughness;
Re
=
ρ
mix
v
mix
(
t
)
D
a
μ
(
10
)
In the above equations, μ is a viscosity of drilling liquid, D o is a wellbore diameter, D i is an outer diameter of the drilling tool within the wellbore.
The change in the hydrostatic column pressure during the drilling can be determined according to the equation (6).
The wellhead back pressure is calculated as follows:
P
w
(
t
)
=
P
w
0
-
Δ
P
h
(
t
)
+
Δ
P
safe
(
11
)
Δ
P
h
(
t
)
=
-
(
ρ
1
-
ρ
g
)
V
g
V
gH
(
12
)
In the equations:
ΔP safe is an additional safety pressure value;
P w0 is a wellhead back pressure when no overflow occurs.
In order to prevent occurrence of accidents, the hydraulic calculation model as shown in equations (1)-(10) can be corrected in real time by the annular pressure data collected by the PWD downhole pressure measurement-while-drilling tool, so as to greatly optimize and improve the precision of the wellbore dynamic pressure calculation model; the optimized hydraulic calculation model can be used for the real-time calculation of the dynamic hydraulic parameter for the managed pressure wellbore under various working conditions.
As described above, when checking is performed, the annular pressure lost checking and/or the wellhead back pressure checking can be used. Generally, when PWD signals can be obtained, the annular pressure lost checking can be employed; when the PWD signals cannot be obtained, the wellhead back pressure checking can be employed.
The annular pressure lost can be checked according to the following equations:
The checked annular pressure lost is:
P
f
(
t
)
new
=
f
′
ρ
mix
(
t
)
H
(
t
)
v
mix
2
(
t
)
2
D
a
In the equation:
Δ P ( t )= P b ( t )− P pwd ( t ) (13)
P′ f ( t )= P f ( t )−Δ P ( t ) (14)
Then a checked annular coefficient of friction resistance is:
f
′
=
P
f
′
(
t
)
P
f
(
t
)
·
f
(
15
)
In the equations:
P pwd (t): the bottom hole pressure value measured by the PWD pressure measurement-while-drilling tool at time t;
ΔP(t): a difference between the calculated bottom hole pressure and the PWD measured value.
ρ mix ( t ) = m g ( t ) + m l ( t ) V ( t ) ;
H(t) is the actual depth-chilled at time t;
v mix ( t ) = Q mix ( t ) A ;
Q mix (t) is the measured value (volume flow) by the mass flowmeter at time t; A is the annular flow area; and D a is a hydraulic diameter.
The wellhead back pressure can be checked according to the following equations:
The checked bottom hole pressure is: P′ b ( t )=α P b ( t ) (16)
The checked wellhead back pressure is: P′ w ( t )= P′ b ( t )− P h ( t )− P f ( t ) (17)
In the equations:
α
=
P
pwd
(
t
)
P
b
(
t
)
(
18
)
α: is a ratio between the measured pressure value by PWD and the calculated value of the bottom hole pressure at time t; the choke valve can be controlled based on the wellhead pressure.
FIG. 2 shows the wellbore dynamic pressure correction provided in an embodiment of the invention. In this embodiment, to facilitate understanding, first three steps present in the existing art are added. As shown in FIG. 2 , during the correction process, basic parameters for calculation of the wellbore pressure are acquired at first, for example, including the non-real time measurement parameters such as an known wellbore structure, a make-up of string and size, a density of drilling liquid, performance and the like, and real-time measurement parameters which are dynamically acquired in real time such as bottom hole pressure, wellhead back pressure, chilling liquid flow rate, volume change of the drilling liquid circulating tank and the like. Then, boundary conditions for the MPD can be determined. For example, according to requirements for the MPD emergency technique, the boundary conditions may be that: the upper limit of the wellhead back pressure is about 5-7 MPa, the content of hydrogen sulfide is less than 20 ppm and the overflow amount is not more than 1 m 3 . And then the bottom hole pressure and the annular pressure lost can be calculated according to the wellbore dynamic flow equation (i.e., the hydraulic calculation model). Then the annular pressure lost or wellhead pressure can be checked according to the solutions provided in embodiments of the invention, and the wellbore dynamic pressure calculation model can be modified by the checked annular pressure lost or wellhead pressure; the MPD is performed according to the model, that is, the checked annular pressure lost or wellhead pressure is used as a target value, which is used for controlling the choke valve aperture by a wellhead throttling manifold system, to adjust the wellhead back pressure, and thereby to accurately control the bottom hole pressure. The difference between the calculated bottom hole pressure and the actually measured bottom hole pressure can be used to adjust an annular checking coefficient in the hydraulic calculation model.
While some preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, the present invention is not limited to the specific details in those embodiments. Various simple modifications can be made to the technical solutions of the present invention within the technical conceptual scope of the present invention, and these simple modifications belong to the protection scope of the present invention.
In addition, it should be appreciated that the technical features described in the above embodiments can be combined in any appropriate manner, provided that there is no conflict among the technical features in combination. To avoid unnecessary iteration, such possible combinations are not described here in the present invention.
Moreover, different embodiments of the present invention can be combined freely as required as long as the combinations do not deviate from the spirit of the present invention. Such combinations shall also be deemed as falling into the scope disclosed in the present invention. | This invention discloses a method for wellbore pressure correction. The method comprises: measuring a bottom hole pressure using a downhole pressure measurement-while-drilling tool; calculating a predicted bottom hole pressure; and correcting a wellbore pressure using the measured bottom hole pressure and the predicted bottom hole pressure, to achieve managed pressure drilling (MPD). The invention makes up for the defect in the existing art that the difference between a wellbore pressure calculation processing method and the actual downhole pressure is relatively great, and is capable of more quickly and accurately calculating the wellbore pressure in real time so that accurate calculation and real-time correction and control of dynamic wellbore pressure on a narrow density window formation are achieved, thereby meeting the requirement of good bottom hole pressure and the requirement of ensuring safe and quick drilling. | 4 |
BACKGROUND OF THE INVENTION
The present invention relates to powered attaching devices for soft goods, and more particularly means for adapting powered attaching devices to thick, bulky goods.
The attaching apparatus of the present invention accommodates assemblies of attachment members of the well-known type illustrated at 11 in FIG. 1, including a thin flexible filament 12 and two ends 13. These individual attachment members are coupled by neck portions 14 to a bar or rod 15, forming an assembly 10. These attachments may be used for numerous purposes compatible with the insertion of a needle into articles, using attaching devices of the type disclosed, for example, in U.S. Pat. Nos. 3,103,666 and 3,470,834. The attaching process involves the severing of an individual fastener 11 at the neck portion 14, and the insertion of one end 13a and the filament 12 through two items to be coupled. Insertion is accomplished by means of a hollow needle through which the attachment member is forced.
FIG. 2 shows a hollow needle 16 which is elongately slotted along one side. To attach a tag, for example, the needle 16 is first inserted through an opening 18 of a tag 17 and then through the weave of fabric 19 to which the tag is to be attached. The end 13 of individual attchment member 11 is then driven through the needle 16 with the filament 12 extending through the needle's slotted side. As the attachment 11 proceeds through the tag 17 and fabric 19, the filament 12 will be bent back parallel to the end 13 as shown in the drawing to permit the passage of the attachment.
U.S. Pat. Nos. 3,734,375 and 3,735,908 disclose improved versions of these earlier attaching devices. These patents disclose a fluid powered attaching device involving the same insertion principle as that of U.S. Pat. No. 3,103,666; the needle is moved pneumatically and fasteners are forced therethrough by similarly powered means.
Particular requirements exist for attaching applications involving abnormally high stresses in the fastening process, as for example the attachment of items to thick goods such as heavy socks. The attaching needle in such applications undergoes significant torque during the penetration of thick goods. This torque, if transmitted to the attachment member to be inserted, is likely to cause the member to fracture, particularly at the junction of filament 12 and one end 13. Of course, the use of internally powered attaching devices is preferable for these applications in order to avoid undue operator fatigue. The fluid powered attaching assemblies of the prior art are inadequate from the above criteria.
Accordingly, it is a principal object of the invention to provide an internally powered attaching device for the attachment type described above. A related object is to minimize operator fatigue for attaching applications involving heavy goods.
Another object of the invention is the avoidance of fastener breakage during the operation of the attaching device. It is undesirable in this regard for attachment members to undergo significant torque during the attaching process.
SUMMARY OF THE INVENTION
In furthering the above and related objects, the powered attaching assembly of the invention provides means for clamping thick, bulky items while inserting a fastener of the above described type. The assembly includes a fastener inserting device which may be fluid powered, a receiver cylinder which is raised and lowered by an air cylinder, a supporting structure, and fluid supply lines and control.
In accordance with a preferred embodiment of the invention, the fastener inserting device includes a projectible member, which houses a fastener dispensing needle. The projectible member is lowered in conjunction with a movable jaw in response to a fluid impulse in the fastener inserting device, and a fastener is forced through the needle by similar means. In accordance with a related aspect of the invention, the receiver cylinder is raised simultaneously with the lowering of the projectible member and movable jaw in conjunction with the motion of a piston within the air cylinder. A workpiece placed upon the receiver cylinder is thereby compressed preparatory to the insertion of an attachment member.
In accordance with another aspect of the invention, the receiver cylinder contains a cavity which allows the incursion of the needle when the projectible member and receiver cylinder converge. The cavity is shaped so as to ensure that an attachment member ejected from the needle will be properly oriented to avoid twisting, minimizing the risk of fracture.
BRIEF DESCRIPTION OF THE DRAWINGS
The above and additional aspects of the invention are illustrated with reference to the foregoing discussion of the prior art, the detailed description of the invention which follows, and the accompanying drawings in which:
FIG. 1 is a plan view of a prior art fastener of the type preferably employed in the invention;
FIG. 2 is a plan view of a needle dispensing a fastener of the general type shown in FIG. 1, in order to attach a tag to fabric in accordance with the prior art;
FIG. 3 is an elevation view of a fluid powered attaching assembly, in accordance with a preferred embodiment of the invention;
FIG. 4A is a cross sectional view of the receiver cylinder of FIG. 3, as seen from the side;
FIG. 4B is a cross sectional view of the receiver cylinder as seen from below, in a section 4B--4B of FIG. 4A;
FIG. 4C is a cross sectional view of an alternate receiver cylinder as seen from above; and
FIG. 5 is a fragmentary side sectional view of the fastener dispensing area during the operation of the fluid powered attaching assembly of FIG. 3.
DETAILED DESCRIPTION
Reference should now be had to FIGS. 1 through 5 for a detailed description of the powered attaching assembly of the invention. The assembly, shown in the elevation view of FIG. 3, comprises a fastener inserting machine 20, a receiver cylinder 30, an air cylinder 40, air supply lines and control 50, and a mounting assembly 60.
The fastener inserting machine 20 is advantageously of the type disclosed in U.S. Pat. Nos. 3,734,375 and 3,735,908. The machine 20 illustratively includes a machine housing 21, a cylindrical housing 22, a projectible member 23 which holds a needle 24, and a movable jaw 25. High pressure air is supplied to cylindrical housing 22 by an air line 53, as regulated by a control module 57. Cylindrical housing 22 contains mechanisms, as disclosed for example in the above-cited patents, which cause the lowering of movable jaw 25 and projectible member 23. The projectable member 23 moves telescopically out of the cylindrical housing 22 when air pressure is applied. The cylindrical housing 22 is fixed to the machine housing 21 and the application of air pressure within the cylindrical housing 22 causes the projectable member 23 to move telescopically out of the cylindrical housing 22. Movable jaw 25 contains a hole 25h which permits the passage of needle 24. Also disclosed are internal means for causing the expulsion of an attachment member through a slot in the needle.
The above attaching device is well suited to the task of compressing layers of material and similar items in order to allow penetration by the needle 24 and the release of an attachment member. Also necessary for this purpose is a second jaw, anvil, or other suitable opposing member (of. FIG. 26 in U.S. Pat. No. 3,734,375) in order that the workpiece may be compressed during the fastening process. The attaching assembly of the invention incorporates a structure enabling the processing of dense materials, while minimizing the risk of fracturing an attachment member.
With further reference to FIG. 3, the attaching assembly includes a receiver cylinder 30 and an air cylinder 40, located on a common vertical line with fastener inserting machine 20. Air cylinder 40 contains a piston (not shown) which is coupled to receiver cylinder 30, so that the introduction of an air impulse through an air line 51 lifts the receiver cylinder. After termination of the air pulse, the piston and receiver cylinder revert to the lower, idle position.
FIG. 4A, which shows a section of receiver cylinder 30 as seen from the side, reveals a cavity 35 of suitable dimensions to allow the insertion of needle 24. In the sectional plan view FIG. 4B of receiver cylinder 30, cavity 35 has a narrow oval profile. The cavity 35 is configured to allow the insertion of the needle 24, while limiting the rotation of the fastener attachment member around the axis of its filament after expulsion from the needle. This design for receiver cylinder 30 is particularly suited to the task of attaching display members such as those commonly known as "headers" to thick items, as can be seen with reference to the partial sectional view of FIG. 5. A layer 19' of thick material is surrounded by display members 17'a and 17'b, which include openings 18'a and 18'b which are provided to facilitate the entry of the needle 24 into and out of the layer 19'. Layer 19' and display members 17' are shown highly compressed between movable jaw 25 of inserting device 20, and receiver cylinder 30. The needle 24 has penetrated material 19' and display members 17', and is shown releasing one end 13a of attachment member 11, the site of release being the cavity 35 in receiver cylinder 30.
In normal operation of the attaching assembly, following the release of attachment member 11, needle 24 will be retracted and movable jaw 25 will rise while receiver cylinder 30 drops. As it is generally desirable to bind layer 19' tightly with attachment member 11, the tendency of layer 19' to rapidly expand when freed from the confining jaws will result in considerable stress on the relatively short attachment member. During the process of inserting needle 24 through the compressed layers, the needle and attachment member 11 undergo significant stress, causing a bending of filament 12 by the folding of the filament 12 towards the end member 13a. When the projectable member 23 is in its uppermost position (e.g. as shown in FIG. 3) any attachment member 11 with an end 13a in the bore of the needle 24 has its associated filament projecting outwardly through a slot of the needle 24. As the needle 24 enters the material being compressed at the level of the filament 12, subsequent movement of the needle into the material bends the filament upwardly with the lower connection of the filament turned towards the end member 13a and the remaining length of the filament being pivotted upwardly against the length of the needle as shown in FIG. 5. This twisting, combined with the stress following ejection of the attachment member, might result in fracture of the attachment at the junction of one end 13 and the filament 12. When released within the confines of cavity 35, however, the end 13a of attachment 11 is naturally oriented along the long axis of that cavity (see FIG. 4B). This reorientation comes about because the release of the end member 13a from the bore of the needle 24 in the cavity 35 removes the force exerted by the interior bore of the needle against the end member and allows it to unfold and resume substantially the right angular position with respect to the filament illustrated in FIG. 1. It is this release of the bending force on the filament 11 that reduces the bending stress, and prevents fracture of the member 13a when the layer 19' is freed from the confining jaws 25 and 30. By orienting cavity 35 to restore attachment member 11 to its natural, untwisted state, the danger of fracture is significantly reduced.
Cavity 35 should have horizontal cross-sectional dimensions which take into account the dimensions of attachment member 11 as well as the thickness of the workpiece to be handled by the attaching assembly. As indicated in FIG. 4C, the receiver member 30 can also have a cavity 35 which is of essentially rectangular configuration as seen in a cross sectional plan of the cylinder transverse to the direction of motion of the projecting member 23. In general the cavity 35 is of a relatively narrow oval configuration of dimensions which allow the insertion of the needle 24 while limiting the rotation of the fastener attachment member 11 around the axis of its filament 12 after expulsion from the needle 24. It is desirable to provide a certain surplus over the dimensions of an end 13, although the narrower dimension of cavity 35 must be smaller than the length of end 13. A greater surplus is needed when processing thicker materials.
Mounting assembly 60 advantageously is of a sturdy design in order to resist the torque which is naturally exerted upon the fastener dispensing device 20 during repeated attaching operations.
While various aspects of the invention have been set forth by the drawings and the specifications, it is to be understood that the foregoing detailed description is for illustration only and that various changes in parts, as well as the substitution of equivalent constituents for those shown and described, may be made without departing from the spirit and scope of the invention as set forth in the appended claims. | An assembly for inserting attachment members through thick, bulky goods, the attachments being of the type including two end pieces connected by a thin, flexible filament. The assembly includes a fluid powered fastener inserting device, a receiver cylinder, an air cylinder, and mounting structure. A fastener dispensing needle held in a projectible member is lowered from the fastener inserting device while the receiver cylinder is raised by the air cylinder, compressing the workpiece therebetween. One end of an attachment member is inserted by the needle through the workpiece, and emerges in a cavity of the receiver cylinder, the cavity being configured to minimize stress on the attachment member during this process. | 3 |
CROSS-REFERENCE TO PRIORITY APPLICATIONS
[0001] This application claims the benefit of and priority to U.S. Provisional Patent Application Ser. No. 61/717,664, filed Oct. 24, 2012, in the U.S. Patent and Trademark Office. This application incorporates the earlier provisional application by reference in its entirety.
BACKGROUND OF THE INVENTION
[0002] The invention relates to a system for automatically monitoring, regulating, and removing contaminants from a structure housing a body of liquid and for introducing the proper amount of outside air to maintain a negative pressure in the structure. The invention also provides a method for evacuating contaminants and water vapor from an enclosure housing a swimming pool.
[0003] In one embodiment of the invention comprises a perimeter drain assembly extending around the swimming pool, at least one conduit in communication with a channel defined by the drain assembly, at least one port in the conduit for directing air, at least one port in the conduit for directing liquid, at least one exhaust conduit, and at least one exhaust apparatus for drawing and directing the contaminants and water vapor to a desired area separate and apart from the swimming pool enclosure or facility.
[0004] In another embodiment, the invention provides a method for evacuating contaminants and water vapor from an enclosure housing a swimming pool comprising the steps of directing a flow of air against and/or across the surface of a swimming pool, creating a zone of containment for contaminants and water vapor substantially above the swimming pool, and evacuating the contaminants and water vapor across the pool surface into at least one port defined by the conduit and into an exhaust system.
[0005] The chemicals used to treat water in a swimming pool create contaminants that may be harmful to swimmers and others present within an enclosure housing a swimming pool (e.g., a natatorium). The water in the swimming pool also creates water vapor (i.e., humidity) within the swimming pool facility. The contaminants (e.g., chloramine) can irritate the eyes and air passages of individuals in and around the pool area. The contaminants such as chloramine are present in the air within the swimming pool enclosure, but are concentrated in an area immediately above the surface of the swimming pool. Unfortunately, greater amounts of chloramine are created when the swimming pool is in use due to swimmers agitating the water (e.g., swimming and splashing).
[0006] Moreover, the high humidity within the enclosure creates an uncomfortable environment for individuals and can affect the physical structure (e.g., girders and roofing) forming the enclosure (e.g., corrosion).
[0007] Moreover, the high humidity formed within the enclosure housing a swimming pool requires that a heating, ventilating, and air conditioning (HVAC) system run almost continuously to circulate and dehumidify the air contained within the enclosure. In addition, the HVAC system runs nearly continuously to circulate the air in order to avoid high concentrations of contaminants in the air.
[0008] It is desirable therefore to reduce the levels of contaminants and humidity within the enclosure housing a swimming pool. Moreover, it is desirable for swimming pool facilities to improve the efficiency of the HVAC system in order to reduce costs associated with circulating, filtering, and dehumidifying the air within the swimming pool facility.
[0009] Accordingly, the present invention addresses the requirements for an energy-efficient apparatus and method for evacuating contaminants and water vapor from a swimming pool facility.
SUMMARY OF THE INVENTION
[0010] The invention comprises in one embodiment a perimeter exhaust plenum or deck drain/exhaust plenum assembly extending around the swimming pool, at least one conduit in communication with a channel defined by the deck drain assembly, at least one port defined by the conduit for directing air, at least one port defined by the conduit for directing liquid, at least one exhaust conduit, and at least one exhaust apparatus for drawing and directing the contaminants and water vapor to a desired area separate and apart from the swimming pool facility. The evacuation system may include bench seating with ports for positioning adjacent the surface of a pool and for receiving air flow therein that can be directed to an appropriate exhaust system.
[0011] In another embodiment, the invention provides a method for evacuating contaminants and water vapor from an enclosure housing a swimming pool comprising the steps of directing a flow of air against the surface of a swimming pool, creating a zone of containment for contaminants and water vapor substantially above the swimming pool, and evacuating the contaminants and water vapor across the pool surface into at least one port defined by the conduit and into an exhaust system.
[0012] In yet another embodiment, the invention comprises an assembly mounted to a wall adjacent the body of liquid. The assembly is comprised of a top section, opposing side sections connected by the top section, and at least one flange extending from an edge of at least one side section. The assembly also includes at least one port connected to a conduit wherein the port directs contaminants and water vapor from a surface of the body of liquid into said conduit, and the conduit evacuates the contaminants and water vapor from the body of liquid. The flange may secure the assembly to a wall adjacent the body of liquid. The flange may include at least one opening for securing the assembly to the wall.
[0013] In another embodiment, the wall-mounted assembly or the bench assembly is a two-piece or three-piece assembly. Specifically, the assemblies may include two or more side sections and top sections.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] The foregoing and other objects and advantages of the invention and the manner in which the same are accomplished will become clearer based on the following detailed description taken in conjunction with the accompanying drawing in which various embodiments of the invention are depicted.
[0015] FIG. 1 is a schematic view of one embodiment of the invention;
[0016] FIG. 2 is a schematic view of another embodiment of the invention;
[0017] FIG. 3 is a schematic view of another embodiment of the invention; and
[0018] FIG. 4 is a schematic view of another embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0019] The present invention will now be described more fully hereinafter with reference to the accompanying drawings, in which a preferred embodiment of the invention is shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout.
[0020] The invention 10 comprises in one embodiment a perimeter deck drain assembly 11 extending around a body of water (e.g., swimming pool 17 ), at least one conduit 12 positioned substantially adjacent to the deck drain assembly, at least one exhaust conduit 13 for evacuating contaminants and water vapor, and at least one exhaust apparatus 14 for drawing and directing the contaminants and water vapor to a desired area. The embodiments of the invention disclosed herein are adapted to be integrated with an HVAC system associated with standard swimming pool construction as well as standard chloramines evacuation systems.
[0021] As shown in FIGS. 1 and 3 the deck drain assembly extends around the swimming pool and includes a bottom panel 15 and two side panels 16 A, 16 B extending vertically from opposing edges of the bottom panel. The deck drain assembly defines a channel 20 for collecting and circulating liquid (e.g., pool water). A grate or grate sections 21 may cover the channel. The gutter assembly may be formed from any number of materials suitable for pool construction such as concrete, stainless, polyvinyl chloride (PVC), fiberglass, or tile.
[0022] The conduit 12 is in communication with the channel 20 and is positioned substantially adjacent thereto. For example, in one embodiment the conduit 12 is secured to one of the side panels 16 A, 16 B opposite the side panel adjacent to the pool. Stated differently, the conduit 12 may be secured to a back side panel of the deck drain assembly. In one embodiment, the conduit is positioned slightly above the side panels.
[0023] It will be understood that the conduit may be formed from any number of materials suitable for construction in connection with swimming pools. For example, the conduit 12 may be formed from polyvinyl chloride (PVC), stainless steel or concrete.
[0024] The conduit 12 defines at least one port 22 for directing air and at least one port 23 for directing liquid. It will be understood that any number of ports for directing air and fluid (e.g., water) may be positioned about the conduit and perimeter deck drain assembly. Moreover, the ports 22 , 23 for directing air and water may be of varying sizes depending upon the size of the swimming pool and pool facility, and requirements to create a uniform draw to properly evacuate contaminants and water vapor. Depending upon the pool structure, the ports may be formed in the PVC, stainless steel, or concrete forming the perimeter gutter assembly.
[0025] Advantageously, the conduit 12 evacuates contaminants and water vapor suspended above a body of liquid (e.g., swimming pool) when a flow of air 24 traveling across the pool surface enters the channel 20 of the perimeter deck drain assembly and the ports 22 for directing air.
[0026] As shown in FIG. 10 the exhaust conduit 13 for evacuating the contaminants and water vapor is in communication with the conduit 12 . As illustrated in FIG. 10 the exhaust apparatus 14 draws and directs the contaminants and water vapor to a desired area spaced apart from the swimming pool (e.g., an exhaust vent outside of the swimming pool facility).
[0027] In one embodiment depicted in FIGS. 4 a , 4 b , 6 a , and 6 b the port for directing air 22 is positioned above the port for directing liquid 23 . As configured, the port for directing air 22 receives flowing air that is drawn from across the pool surface and into the channel 20 defined by the perimeter deck drain assembly. The port for directing air 22 is positioned above the pool surface and is capable of receiving the flowing air containing contaminants and water vapor from the pool surface as well as from the surface of any water collected in the channel 20 . Stated differently, the uniform draw of flowing air from the pool surface necessarily draws contaminants and water vapor from water collected in the channel 20 of the perimeter deck drain assembly (see FIGS. 4 a and 6 a ).
[0028] In one embodiment, the port for directing air 22 and the port for directing liquid 23 are substantially coplanar with respect to one another (see FIGS. 3 and 4 a ). In other words, the two ports 22 , 23 are formed in the conduit 12 and back panel 16 B of the perimeter deck drain assembly. This particular embodiment is configured for deck drain assemblies wherein a portion of the pool deck 18 extends over the channel of the gutter assembly.
[0029] In another embodiment, the port for directing air 22 and the port for directing liquid 23 are substantially perpendicular with respect to one another (see FIGS. 5 and 6 a ). Stated differently, the port for directing air 22 is coplanar with the pool deck 18 and flowing air containing contaminants and water vapor is drawn through the top of the conduit. This particular embodiment is configured for perimeter gutter assemblies wherein the pool deck 18 is flush or coplanar with the deck drain assembly.
[0030] As shown in FIGS. 4 a and 6 a , the port for directing liquid 23 directs condensed water vapor into the channel. In another embodiment shown in FIGS. 5 and 7 a , the port for directing liquid 23 directs condensed water vapor away from the channel, for example, into a drain 25 . Advantageously, this configuration provides a self-draining feature to the conduit.
[0031] The invention may further include at least one air source 26 for directing a flow of air downward against the surface of the swimming pool 17 as depicted in FIG. 8 . As discussed below, it will be understood that one or more air sources may be incorporated into the subject invention to ensure proper evacuation of contaminants and water vapor, and sufficient recirculation of clean air (i.e., air containing minimal amounts of contaminants and water vapor). In one embodiment, one air source 26 (e.g., HVAC duct) is positioned above the swimming pool 17 in a central location with respect to the pool.
[0032] In operation, the flowing air from the air source 26 creates a zone 30 for containing contaminants and water vapor substantially above and adjacent to the pool surface (see FIG. 8 ). The flowing air creates overpressure above the swimming pool surface and forms the containment zone. It is understood that the air above the pool surface containing contaminants and water vapor is denser than the air emanating from the air source. Advantageously, the flowing air directs contaminants and water vapor from the containment zone 30 across the pool surface and through the conduit 12 into the port for directing air 22 to the exhaust conduit 13 . In this particular embodiment depicted in FIG. 8 , the central location of the air source 26 and the exhaust system draws the air containing contaminants and water vapor across the pool surface in multiple directions in a uniform draw and into the conduit 12 for evacuation by the exhaust system.
[0033] The invention may also include one or more of additional air sources 27 for circulating a flow of air substantially adjacent to the containment zone 30 as depicted in FIGS. 8 and 9 . The additional air sources 27 may be positioned above the pool deck 18 on opposite sides of the swimming pool facility (i.e., on both sides the central air source 26 positioned directly above the swimming pool 17 ). As illustrated, the flowing air from the additional air sources maintains the integrity of the containment zone 30 and facilitates circulation of air substantially adjacent to the containment zone 30 . By doing so, clean air containing less contaminants and water vapor than in the containment zone is circulated adjacent to the containment zone 30 and adjacent to the airflow emanating from the central air source 26 , thereby minimizing contaminants and water vapor (i.e., humidity) in the areas adjacent to the swimming pool.
[0034] Advantageously, the subject invention evacuates contaminants and water vapor where it is most heavily concentrated (i.e., above the pool surface) and prevents the contaminants and water vapor from disseminating throughout the swimming pool facility. Conventional systems merely mix and recirculate air containing contaminants and water vapor continuously in an effort to reduce chloramine and humidity levels within the swimming pool facility by dilution. As configured, the present novel invention works in unison with (i.e., balanced with) the HVAC system to reduce the number of air changes per hour (ACH) throughout the entire facility required to maintain safe levels of contaminants and a comfortable level of humidity and air quality. This is accomplished by evacuating contaminants and water vapor directly from the area most affected—i.e., the air in the containment zone 30 immediately above the swimming pool surface. By focusing evacuation in the containment zone 30 , fewer number of air changes are required in the areas adjacent to the containment zone. In other words, the apparatus affects an area smaller than the entire area of the facility (i.e., the area immediately above the swimming pool surface) and is capable of increasing the number of air changes per hour (ACH) within the containment zone. By doing so, the apparatus 10 reduces the number of air changes per hour (ACH) required in the areas adjacent to the containment zone.
[0035] As depicted in FIG. 9 in an alternative embodiment, the invention may also include yet another air source 28 for directing a flow of air 24 across the surface of the swimming pool 17 from one side of the pool to another. In this embodiment, the additional air source 28 directs a flow of air 24 from one port for directing air 22 to another port for directing air 22 that is positioned opposite thereto. In other words, the additional air source 28 will direct (i.e., sweep) air from one or more ports 22 on one side of a swimming pool, across the pool surface, and into one or more ports 22 on the opposite side of the swimming pool. The flowing air 24 is then directed to the exhaust conduit 13 by the exhaust apparatus 14 .
[0036] The invention may also include an enclosure 31 for housing the apparatus and swimming pool.
[0037] The invention also provides a method for evacuating contaminants and water vapor from an enclosure 31 housing a swimming pool 17 . The method includes the steps of directing a flow of air against the surface of the swimming pool, creating a zone of containment 30 for contaminants and water vapor substantially above the swimming pool, and evacuating the contaminants and water vapor across the pool surface. The contaminants and water vapor are directed into the ports 22 defined by the conduit 12 positioned substantially adjacent to the pool surface and into an exhaust system.
[0038] In summary, the present apparatus and method provides the following advantageous benefits: reduces the level of contaminants and water vapor in the entire enclosure housing a swimming pool; operates in conjunction with HVAC system to remove contaminants, reduce humidity levels in the facility and thereby improve overall air quality; decreases the amount of heat in the facility; reduces the requirement to operate dehumidifiers within the HVAC system; reduces the number of air changes per hour (ACH) required to maintain safe contaminant levels and reduce humidity within the facility; reduces tonnage (i.e., amount of airflow) required of an HVAC system to recirculate and dehumidify air, and to reduce the concentration of contaminants (e.g., chloramine) within the facility; reduces the operating costs of a HVAC system (i.e., compressor and dehumidifier); and improves energy efficiency resulting from the variable operation of the subject invention (i.e., operates during peak demand when the pool is in use and is idle during off hours when the pool is closed); operates during peak demand or upon demand dependent upon humidity levels in the facility.
[0039] Furthermore, the subject apparatus and method decreases the amount of tonnage necessary to circulate and dehumidify air in a swimming pool facility, thereby reducing the size of new enclosures for swimming pools necessary to circulate and dehumidify the air contained therein.
[0040] In addition to new construction, the apparatus 10 is also suitable for retrofit applications for existing swimming pool facilities. By retrofitting existing facilities with the novel apparatus, one may be able to reduce the number of dehumidifiers required to maintain comfortable levels of humidity, or at least minimize the operating time of existing dehumidifiers, thereby improving energy efficiency and reducing operating costs.
[0041] In another embodiment set forth in FIGS. 11 and 12 , the invention comprises a perimeter deck drain assembly 40 extending around at least a portion of a body of liquid (e.g., swimming pool 17 ), at least one tray 41 for directing liquid (e.g., water) secured to lower portions of the gutter assembly 40 , and a grating system 42 for receiving water. The gutter assembly 40 has two side panels 43 a , 43 b , an upper section 44 , and a lower section 45 all of which define at least one conduit 46 for collecting and circulating liquid. In this embodiment, the deck drain assembly 40 may be constructed substantially adjacent to the body of liquid (i.e., swimming pool). In operation, the conduit 46 evacuates contaminants and water vapor suspended above the body of liquid when a flow of air 24 traveling across the body of liquid enters the grating system 42 and conduit 46 . The invention also facilitates evacuation of water vapor and contaminants formed in the conduit 46 when the water is agitated during travel. In this specific embodiment as described in detail below, the deck drain assembly 40 includes a deck drain 47 integral with the evacuation apparatus 10 , wherein the deck drain 47 is flush with the deck 18 of the swimming pool 17 . As shown in FIG. 11B , the tray may be shaped in any desired configuration to assist in draining and may include variously sloped surfaces.
[0042] Advantageously, the upper section 44 of the gutter assembly 40 is adjustable for height and supports the grating system 42 . Specifically, the upper section 44 of the deck drain assembly 40 includes an adjustable neck 48 . As shown in FIG. 1 , the upper section 44 includes a four-sided section 49 having a perimeter that is slightly larger than another portion of the neck. The adjustment feature is shown schematically in FIG. 11A . As configured, the uppermost section of the neck 48 may be adjusted for height depending upon, in one embodiment, the depth of the conduit 46 and the height of a pool deck 18 , and then secured to the remaining lower section 45 of the neck 48 . For example, tack welds can secure the uppermost section of the neck to the remaining lower section 45 of the neck.
[0043] The tray 41 is secured to lower portions of the two side panels 43 A, 43 B of the deck drain assembly 40 . The apparatus may include any number of trays 41 sufficient to form a bottom panel 60 of the assembly. One or more trays 41 may be sloped towards one or more drains such that water entering the grating system 42 and conduit 46 will be directed to the drain for recirculation.
[0044] The grating system 42 is positioned against the upper section 44 of the deck drain assembly 40 . The grating system 42 includes at least one grate section 55 defining a plurality of openings 56 for receiving liquid or water from a swimming pool deck and a support 57 secured to the upper section 44 of the deck drain assembly 40 . The support 57 releasably secures the grate sections 55 to the deck drain assembly 40 . The grate sections 55 having openings 56 may be interspersed with grate sections 55 having no openings depending upon the size and shape of the swimming pool and the requirements for providing sufficient recirculation of the water.
[0045] The invention may also include at least one support member 58 for supporting the gutter assembly 40 . In one embodiment, the support member 58 is secured with rebar to concrete or other material forming the swimming pool.
[0046] The invention may also include at least one exhaust conduit 13 for evacuating contaminants and water vapor, and at least one exhaust apparatus 14 for drawing and directing the contaminants and water vapor to a desired area. The exhaust conduit 13 for evacuating the contaminants and water vapor is in communication with the conduit 46 of the deck drain assembly 40 . The exhaust apparatus 14 draws and directs the contaminants and water vapor to a desired area spaced apart from the swimming pool (e.g., an exhaust vent outside of the swimming pool facility).
[0047] As described earlier, at least one air source 26 for directing a flow of air against the surface of the swimming pool may be provided. In operation, the flowing air from the air source 26 creates a zone 30 for containing contaminants and water vapor substantially above the pool surface. The flowing air directs contaminants and water vapor from the containment zone 30 through the grating system 42 into the conduit 46 and to the exhaust conduit 13 . As depicted in FIG. 2 , the grating system 42 is flush with the deck surface 18 of the swimming pool 17 .
[0048] As previously discussed, this embodiment may also include at least one air source 28 for directing a flow of air 24 across the surface of the swimming pool 17 . This embodiment may further include at least another air source 27 for circulating a flow of air substantially adjacent to the containment zone 30 , such that the flowing air maintains the integrity of the containment zone and facilitates circulation of air substantially adjacent to the containment zone.
[0049] This particular embodiment may also include an enclosure 31 for housing the apparatus and swimming pool.
[0050] A method incorporating this latest embodiment is also provided. The method includes the steps of directing a flow of air against and/or across the surface of the swimming pool, creating a zone of containment for contaminants and water vapor substantially above the swimming pool, and evacuating the contaminants and water vapor across the pool surface, into at least one conduit 46 positioned substantially adjacent the pool surface, and into an exhaust system.
[0051] The invention includes yet another embodiment in which the ports for evacuating contaminants and water vapor are conveniently implemented in the form of a deck bench as illustrated in FIGS. 13-17 . The bench provides a seat around the perimeter of a body of liquid, such as a swimming pool. The front section 65 of the bench assembly 70 defines ports 22 that receive air flow from just above the surface of the liquid. Similar to the embodiments noted above, the ports direct contaminants and water vapor to the appropriate exhaust removal system and drainage system. Air enters a conduit defined by edges of the bench assembly 70 through the ports 22 and exits through an exhaust connector 68 to the appropriate exhaust removal and handling system.
[0052] FIG. 14 shows the air flow entering a respective port 22 , and one should note that the air flow may be controlled in any of the ways described above for other embodiments of this invention so long as contaminants and water vapor efficiently enter the conduit defined by the bench assembly via the ports 22 . Accordingly, the invention may further include at least one air source 26 for directing a flow of air downward against the surface of the water in a swimming pool 17 as depicted in FIG. 8 to push water vapor and contaminants into the ports 22 defined by the bench assembly 70 . As discussed above, it will be understood that one or more air sources may be incorporated into the subject invention to ensure proper evacuation of contaminants and water vapor and sufficient recirculation of clean air (i.e., air containing minimal amounts of contaminants and water vapor).
[0053] FIG. 15 shows that the bench assembly 70 may be formed of modular sections 70 A, 70 B, and 70 C for stacking and easy storage. The sections incorporate connectors (e.g., standard draw catches) that allow the sections to fit together tightly, and a gasket 67 may fit between connected sections to seal the sections together. Each section may also include a rubber foot 69 for sealing the bench assembly 70 to the floor (i.e., a floor seal). Overall, the sections 70 A- 70 C fit to each other and to the floor adjacent a body of liquid to create an air tight enclosure that is connected to an exhaust removal system by an end piece 68 as shown in FIGS. 16 and 17 . The exhaust removal system may be configured to provide a negative pressure level that actually sucks the contaminants and water vapor into the appropriate exhaust removal mechanisms.
[0054] So long as the ports 22 are accessible to the air flow above the body of liquid, the system will efficiently transport contaminants away from the liquid. The bench assembly may be sized as appropriate for the amount of contamination to be removed (e.g., sections of 16 inches by 16 inches allow for 256 square inches of air flow). The body of the bench assembly 70 and its component sections 70 A- 70 C may comprise any materials that are convenient for manufacturing the sections and that can withstand the pressures used in the system. Bench assemblies of molded plastics or shaped metals are within the scope of the invention described herein. The number of ports 22 and the number of sections 70 A- 70 C may be adjusted to fit the use at hand. The bench assembly may be placed in one or more regions around the body of liquid or may encompass the entire perimeter of the body of liquid.
[0055] In yet another embodiment, the invention includes a wall-mounted apparatus. More specifically, the apparatus 100 includes an assembly 110 mounted to a wall 111 adjacent the body of liquid. The assembly 110 is comprised of a top section 112 , opposing side sections 113 , 114 connected by the top section, and at least one flange 115 extending from an edge of at least one of the side sections. In the embodiment appearing in FIG. 18 , the assembly 111 includes two flanges 115 that mount to a wall. The assembly 110 also includes at least one port 116 connected to a conduit 117 , such that the port directs contaminants and water vapor from a surface of the body of liquid into the conduit, and the conduit evacuates the contaminants and water vapor from the body of liquid.
[0056] In one embodiment depicted in FIG. 19 , the flange(s) 115 defines at least one opening 118 for securing the assembly 110 to the wall. It will be understood that the flange 115 may not necessarily include an opening, but can be used in any number of fashions to provide a flat surface for securing the assembly 110 to a wall. In the embodiment illustrated in FIG. 19 , the assembly 110 is secured to the wall by a mounting member 119 . The mounting member 119 can be a screw, a nail, a fastener, bracket, a bolt, or combinations thereof.
[0057] The assembly 110 may also include modular sections 110 A, 110 B, 110 C that fit together on the wall around the body of liquid. The modular sections 110 A, 110 B, 110 C may include connectors 120 for fitting the modular sections to each other. One or more gaskets 121 may be used between pairs of modular sections to maintain an airtight seal. In addition, the assembly 110 may include at least one wall seal 122 to maintain an airtight seal.
[0058] An exhaust connector 124 connecting the conduit 117 to an exhaust removal system is also included in the assembly 110 . One end of the assembly may include an end piece 123 sealing the conduit 117 .
[0059] In another embodiment of the invention, the top section 112 and one of the side sections 113 , 114 of the wall-mounted 110 or bench assembly 70 are integrally formed as illustrated in FIG. 21 , such that the other side section is a separate piece. In this embodiment, at least one end of the top section 112 is releasably secured to one end of one of the side sections 113 , 114 . That said, the top section 112 and the side sections 113 , 114 may also be formed from separate pieces, wherein the top section is releasably secured to the side sections as illustrated in FIG. 22 . Accordingly, in this embodiment, opposing ends of the top section 112 are releasably secured to ends of the side sections 113 , 114 .
[0060] In another embodiment, the invention includes a system for automatically monitoring, regulating and removing contaminants from an area above a body of liquid. The system includes a sensor for monitoring contaminants (e.g., volatile organic compounds or VOCs) mounted to a wall adjacent the body of liquid, an assembly comprising at least one port connected to at least one conduit. The system includes at least one port directing contaminants and water vapor from a surface of the body of liquid into the conduit. The system also includes at least one climate control system for recirculating air into and out of a structure containing the body of liquid, at least one external or outside air damper or fan for the introduction of outside air into the facility, and at least one plasma system for reducing VOCs in the environmental air present in the structure.
[0061] In addition, the invention includes at least one fan for advancing the evacuated air out of the structure and an outside air damper or fan for advancing fresh air into the structure. The regulation of the outside air will correspond with the air flow of the exhaust fan to maintain a slightly negative building pressure, preventing nitrogen chloride (NCl3) gas and other VOCs from entering other occupied spaces in the structure outside of the structure or in one embodiment a natatorium. Advantageously, the conduit evacuates the contaminants and water vapor from the body of liquid.
[0062] The assembly may be retrofitted into an existing structure such as a natatorium. In one embodiment, the apparatus is secured to a wall of the structure by a mounting member. Likewise, the assembly can be independent of an existing exhaust system in the structure.
[0063] For the sake of efficiency, the system includes a controller for monitoring and regulating exhaust and introduction of external or outside air. This system will provide “on demand” control of NCl3 and disinfection by-product.
[0064] The system also includes an exhaust connector for connecting the conduit to an exhaust removal system, an outside air damper or fan for introducing outside air, and an exhaust connected to the exhaust connector.
[0065] In the drawings and specification, there have been disclosed typical embodiments on the invention and, although specific terms have been employed, they have been used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being set forth in the following claims. | A system for automatically monitoring, regulating, and removing contaminants from a structure housing a body of liquid and for introducing the proper amount of outside air to maintain a negative pressure in the structure. The invention comprises a sensor for monitoring contaminants, a port assembly connected to at least one conduit, a controller to receive input from the sensor, a controller programmed to regulate environmental conditions of the structure at a predetermined level correlating to desired air quality in the structure, at least one exhaust fan, a climate control system, a cold plasma ionization system, a control signal from the controller for regulating the introduced outside air into the structure and for advancing fresh air into the structure, and a fresh air damper or fan. | 5 |
BACKGROUND OF THE INVENTION
The present invention relates to a grommet for a wire harness having a resilient inner member which seals and secures a wire harness within a rigid outer member.
A wire harness is commonly formed by bundling a plurality of electrical wires together prior to installation into the body of a vehicle. A wire harness connects one or more electrical components within the vehicle and therefore must be routed through various vehicle partition panels. A tight seal is often required between the partition panel and the harness to prevent leakage of liquid or fumes between compartments of the vehicle. It is further desirable to provide support for the harness relative to the panel through which it passes to prevent abrasion. Thus, it is commonly know to provide a grommet to protect and seal the harness where it passes through the partition panels.
Conventional grommets are formed of an elastic rubber to seal the harness to the partition opening. The rubber grommets are commonly installed by forcibly stretching the grommet to thereby allow axial insertion of the harness. When released the rubber grommet conforms to the harness which is then located within the vehicle partition. However, the stretching and locating operations require substantial effort to insert the harness. Further, if the harness is pulled with some force, the rubber grommet will likely be removed from the partition opening due to the grommet's elasticity.
Other known grommets combine a rigid support with an elastic member to improve retention and protection of the harness within the partition opening. However, due to their complex configurations, known combination grommets provide a less effective seal than the grommet described above and are relatively difficult and costly to manufacture and install.
SUMMARY OF THE INVENTION
This present invention provides a unique wire harness grommet that avoids the problems of the prior art described above. The wire harness grommet of the present invention provides an improved grommet assembly which is assembled in a simple and precise manner to provide an effective seal which can be located along any portion of a wire harness by simply “snapping” it in place.
In general terms, the present invention is a wire harness grommet which is assembled by connecting together a rigid outer member to compress a resilient inner member around a portion of the wire harness accommodated therein.
The rigid outer member is essentially a shell held together by mechanical connectors to contain and compress the resilient inner member into a conformable relationship with the wire harness. This prevents the grommet from being easily removed from the vehicle partition panel when the wires are forcibly pulled. Preferably, the rigid outer member is a two piece assembly comprising generally two identical halves having integrally molded connectors which “snap” together.
The resilient inner member provides the sealing surface between the rigid outer member and the wire harness. The resilient inner member is affixed directly to the rigid outer member and located in a cavity defined by the rigid outer member. Preferably, the resilient inner member is an adhesively backed foam pad which is affixed to and compressed by, the rigid outer members.
Alternatively, the cavity is filled with an adhesive prior to the rigid outer member being connected around the harness. A suitable material for the resilient inner member is a silicon rubber which cures and forms a highly effective seal around the harness.
BRIEF DESCRIPTION OF THE DRAWINGS
The various features and advantages of this invention will become apparent to those skilled in the art from the following detailed description of the currently preferred embodiments. The drawings that accompany the detailed description can be briefly described as follows.
FIG. 1 is an exploded perspective illustration of a grommet assembly according to the present invention;
FIG. 2 is a side view of a rigid outer member of the grommet assembly shown in FIG. 1 receiving an alternate inner resilient member having a divider;
FIG. 3 is a perspective illustration of an alternate grommet assembly according to the present invention; and
FIG. 4 is a perspective illustration of another alternate grommet assembly according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 illustrates a grommet assembly 10 according to the present invention prior to assembly over a wire harness 12 . The grommet 10 includes a resilient inner member 14 which accommodates and seals a portion of the wire harness 12 within a rigid outer member 16 . The rigid outer member is here shown as two separate, diametrically mated halves. The rigid outer member 16 is thus shown as a first and a second rigid outer member containing a resilient inner member 14 provided as a first and a second resilient inner member respectively. The rigid outer members 16 are preferably generally identical to prevent mismatching of parts and to minimize the tooling required to produce the grommet assembly 10 .
The rigid outer member 16 of the grommet assembly 10 is shown in FIG. 2 . The rigid outer member 16 provides structural support for the harness 12 when inserted into a panel opening. A mechanical retainer 20 is preferably integrally molded to the rigid outer member 16 to lock the grommet assembly 10 in the panel opening. A seal 22 , such as a rubber washer or O-ring, can be located between the retainer 20 and the partition panel 23 to seal the grommet assembly 10 and further prevent leakage of fumes or liquids. Therefore, once mated, the rigid outer members 16 , retainer 20 , and seal 22 provide an effective sealing interface between the panel 23 and the harness 12 .
The resilient inner member 14 is substantially surrounded or contained by the rigid outer member 16 to provide a liquid resistant boundary which easily conforms to the shape of any harness 12 contained therein. The resilient inner member 14 can be set within a cavity 24 of the rigid outer members 16 or can be directly affixed thereto. Preferably, the resilient inner member 14 is an adhesively backed closed cell foam pad which is directly affixed to the rigid outer member 16 providing an effective yet simple to manufacture seal.
The resilient inner members 14 can further include a divider 18 projecting substantially perpendicular to the axis of each resilient inner member 14 . The divider 18 is positioned between the wires of the wiring harness 12 (FIG. 2) to provide further retention of the grommet assembly 10 in a specific position on the wire harness 12 . The divider 18 therefore contacts the opposing divider 18 and is compressed within the rigid outer members 16 .
To allow effective compression and sealing, the resilient inner members 14 extend from the cavity 24 in the rigid outer members 16 . Thus, when the rigid outer members 16 are mated, the resilient inner members 14 are compressed to conform around the harness 12 shape to form a tight seal therebetween. When the grommet assembly 10 is installed in the partition opening the radial compression of the resilient inner member 14 is further increased and thereby maintains the highly effective seal.
The individual rigid outer members 16 are attached to each other by connectors 30 , which are preferably integrally molded to the rigid outer members 16 in male and female configurations. The connectors 30 thereby allow the rigid outer members 16 to be simply “snapped” together to form the complete grommet assembly 10 . By providing each rigid outer member 16 with a female and a male connector the parts can be identically produced to thereby prevent the mismatching of parts and the minimization of duplicative tooling.
FIG. 3 illustrates an alternate embodiment of the grommet assembly 40 of the present invention. The cavity 44 defined by the rigid outer member 46 is used to contain the foam pad (FIG. 1) or can be filled with an adhesive material. One skilled in the art will realize that various thermosetting or thermoplastic adhesive materials can be used to form the resilient inner member 42 . In this alternate embodiment, an adhesive such as silicon is used as the resilient inner member 42 . The cavity 44 is filled with adhesive either before or after the harness is inserted between the rigid outer member 46 . Preferably, the adhesive material is injected into the cavity and the harness 12 is placed into the adhesive. The rigid outer member 46 is then connected together around the harness 12 and the adhesive is allowed to cure within. The adhesive thus provides an effective vapor resistant seal between the rigid outer member 46 and the harness 12 .
The grommet assembly 40 is substantially similar to the embodiment described above, but the first and second rigid outer members 46 are formed as a single unit. The rigid outer member 46 preferably includes an integral hinge 48 providing a location where the rigid outer member 46 is spread apart. The integral hinge 48 can be of any known configuration which allows opening of the one-piece rigid outer member 46 to provide placement of the harness 12 into the cavity 44 .
In the embodiment illustrated by FIG. 3, the rigid outer member 46 is substantially C-shaped in cross section to define the cavity 44 . The one-piece C-like shape thus provides a cavity 44 which is highly effective in containing the adhesive while still in a liquid or semi-liquid state. The rigid outer member 46 is spread open along the hinge 48 , adhesive is injected into the cavity 44 and the harness 12 is placed within the adhesive. The grommet assembly 40 is then locked closed with the connectors 49 , the adhesive cures, and the harness 12 is sealed and protected within the cured adhesive and rigid outer member 46 .
FIG. 4 illustrates another alternate embodiment of the grommet assembly 50 of the present invention. The grommet assembly 50 is substantially similar to the embodiments described above, but the rigid outer member 52 is formed as a substantially plate-like configuration. This configuration provides an effective yet substantially planar sealing surface where a harness 12 is passed through, for example only, thin sheet metal. In this embodiment the planar rigid outer member 52 is twisted open to accommodate the wire harness 12 within the resilient inner members 54 and is then locked closed by the connectors 56 .
The foregoing description is exemplary rather than limiting in nature. Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described. | A wire harness grommet assembly which is assembled by connecting together a rigid outer member to compress a resilient inner member around a portion of the wire harness accommodated therein. The resilient inner member provides a sealing surface between the rigid outer member and the wire harness. Accordingly, the resilient inner member is compressed when sandwiched between the locked together rigid outer members. Preferably, the rigid outer member is a two piece assembly comprising two identical rigid outer members having integrally molded connectors which allow the grommet assembly to be “snapped” together around the harness. | 1 |
RELATED APPLICATION INFORMATION
This application is a continuation in part of U.S. application Ser. No. 07/831,175 filed Feb. 5, 1992.
BACKGROUND OF THE INVENTION
The present invention relates to waste processing systems and, more particularly, to waste processing systems for handling hazardous or radioactive waste which must be totally enclosed to maintain a specified environment and in which material is dumped and shredded before being conveyed for further treatment or incineration.
Environmental laws require that hazardous material, including radioactive material, either be incinerated, stabilized or processed under certain prescribed conditions, or collected, packaged and stored at special sites. In any case, it is desirable to reduce the particle size of the material as much as possible. In the case of material to be incinerated, small particle size insures more complete combustion and facilitates feeding into an incinerator. In the case of material to be packaged, reduction of particle size allows a greater amount of material to be shipped within a given container. In the case of materials to be stabilized, small particle size insures more complete stabilization. In the case of material to be processed in a slagging mode incinerator, small particle size insures more complete breakdown of materials.
Since the handling of such material may give rise to toxic or radioactive fumes, or create the hazard of an explosion, it is desirable to process such material in enclosed environments. For example, in Robertson U.S. Pat. No. 5,022,328, there is disclosed a system in which containerized waste is conveyed upwardly through an elevator, then horizontally to an air lock where the containerized waste is dumped through a drop chute into a shredder device which grinds the waste material and containers, then is injected by a feed screw into an incinerator. A disadvantage with this system is that the material is elevated and conveyed horizontally in a system which is not enclosed or protected from the environment. Further, the system disclosed in the Robertson patent is not capable of receiving and dumping hazardous or radioactive material from reusable containers. Accordingly, there is a need for a waste processing system in which material can be received at ground level or intermediate levels, then processed for storage, stabilization, incineration or additional processing in a totally enclosed environment at a different level. Further, such a system should be able to handle reusable containers.
SUMMARY OF THE INVENTION
The present invention is a waste processing system adapted to handle hazardous and radioactive containerized material in which the material is received substantially at ground level or intermediate levels, is elevated, dumped, the material is shredded, blended, mixed, homogenized or combined with stabilizing agents, and is injected into an incinerator or a container or into an additional processing stage. The entire system is enclosed and maintained in a low oxygen or inert gas environment. Gas pressure within the system can be maintained positive (greater than atmospheric) or negative (less than atmospheric) as the application requires. As a result, the likelihood of contamination reaching the ambient during the elevating, dumping, shredding and injecting processes is substantially reduced, as is the likelihood of explosion.
The system includes one or more powered infeed conveyors, each having its own air lock. Each air lock has inner and outer doors which include a sliding door member that is supported entirely about its periphery when closed and is sealable. These door seal assemblies can be of conventional mechanically-loaded lip or inflatable design. Seals can be located on one side of the door or on both sides, providing redundant protection. Accordingly, the doors are better able to withstand explosions than prior art air lock doors, and yet are of a relatively simple construction.
The air locks are connected to a totally enclosed, substantially vertical elevator having a powered conveyor on the elevator platform for receiving containerized waste from one or more air locks. The elevator platform elevates the containerized waste to a dual purpose discharger. The discharger includes primary and auxiliary ram members. If the waste is in disposable containers, the primary ram member transports the containers horizontally from the elevator to be dropped into the shredder. If the waste is in reusable containers, the ram member grips the container, transports the container to a position above the shredder, inverts the container to dump the contents, uprights the container and retracts it to the elevator for return to the air locks empty.
Should the size of the container dictate, the auxiliary ram member operates synchronously with the primary ram member to grip the container from the side opposite the primary ram member. Disposable containers would include such items as 55 gallon drums, Gaylord containers, 300 gallon liquid packs and the like. The ram members are displacable horizontally by motorized ball screws. The clamping component of the ram members includes a clamping frame on which are mounted two or more clamping fingers that are advanced horizontally by a pair of hydraulic cylinder motors and are clamped toward and away from each other by a third hydraulic cylinder motor. The clamping frames are rotated, when a reusable container is dumped, by a linear or rotary actuator powered by a hydraulic cylinder motor.
The drop chute is a contained housing having explosion doors in the ceiling and communicates with a dual auger shredder. The dual auger shredder discharges through material discharge doors into a single auger shredder, which, in turn, discharges sidewardly into a feed screw that pumps the material horizontally into an incinerator, container or additional processor. A rotary gate is mounted downstream of the injector feed screw and can be opened or closed to prevent burn-back and escape of material.
A slide box is mounted downstream of the gate and includes a pair of conduit segments. The first conduit segment interconnects the feeder screw with an incinerator mounted on an opposite side of the slide box. The second conduit segment has an open bottom and a deflector plate to deflect material downwardly into a receptacle or other container for transportation.
Accordingly, it is an object of the present invention to provide a waste processing system in which waste material is received at ground level or intermediate levels, is elevated, dumped, shredded, blended and fed to an incinerator, container or additional processor, all in an enclosed environment in which the atmosphere may be maintained in a low oxygen or inert gas environment; a waste processing system in which the inlet air locks include sliding doors which are supported about their entire peripheries when closed and are sealable; a waste processing system in which a discharger transports containerized waste horizontally to a drop chute and can displace disposable containers and a pallet on which they are carried or reusable containers, the latter of which are dumped and returned to ground level; a waste processing system in which the ground and shredded waste material can be pumped directly into an incineration device, or to a container or additional processing machinery for further treatment or shipping; and a waste processing system which is relatively safe to operate and relatively easy to maintain.
Other objects and advantages of the present invention will be apparent from the following description, the accompanying drawings and the appended claims.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a somewhat schematic, perspective view of a waste processing system incorporating the present invention;
FIG. 2 is a detail of the system of FIG. 1 showing an infeed conveyor and air lock, in which the side panels of the air lock have been removed;
FIG. 3 is a detail of the system of FIG. 1 showing an air lock door;
FIG. 4 is an exploded, perspective view of the door assembly of FIG. 3;
FIG. 5 is a section taken at Line 5--5 of FIG. 3 in which the center section has been broken away;
FIG. 6 is a detail showing the elevator and discharger structure in which the side panels have been removed to show the interior of these components;
FIG. 7 is a detail of the discharger of FIG. 6 showing the ram members;
FIG. 8 is an exploded, perspective view of the ram members of FIG. 7 and a canister;
FIG. 9 is a detail showing the discharger of FIG. 6 in which a reusable canister is positioned on the elevator platform;
FIG. 10 is the detail of FIG. 9 in which the opposing ram member is engaging the canister;
FIG. 11 is the detail of FIG. 9 in which the canister has been transported to the drop chute area;
FIG. 12 is the detail of FIG. 11 in which the canister has been inverted to dump its contents;
FIG. 13 is a detail of the discharger of the system of FIG. 1 in which disposable containers are supported on the elevator platform;
FIG. 14 is a detail of the system of FIG. 1 showing a schematic side elevation of the shredder and injector components;
FIG. 15 is a detail showing a perspective view of the slide box of the system of FIG. 1;
FIG. 16 is a section taken at Line 16--16 of FIG. 15;
FIG. 17 is a section taken at Line 17--17 of FIG. 15;
FIG. 18 is a schematic showing the controller component of the system of FIG. 1;
FIG. 19 is a schematic showing the controller of FIG. 17 and the connections for operating the ram carriages;
FIG. 20 is a schematic, perspective view of an alternate embodiment of the waste processing system of the present invention, utilized with a rotary kiln having an elevated infeed shoot;
FIG. 21 is a perspective view of the waste processing system of a second alternate embodiment of the present invention feeding a sag mill having an elevated inlet;
FIG. 22 is a schematic, perspective view of the waste processing system of a third alternate embodiment of the present invention in which a rotary kiln fed by the system is at a different elevation than the infeed and outfeed conveyors; and
FIG. 23 is a perspective view of the waste processing system of a fourth alternate embodiment of the present invention in which a second infeed conveyor is utilized.
DETAILED DESCRIPTION
As shown in FIG. 1, the waste processing system of the present invention includes an infeed conveyor 20, an outfeed conveyor 22, elevator 24, discharger 26, hopper extension 28, dual auger assembly 30, single auger assembly 32, injector 34, and slide box 36. The aforementioned components all are totally enclosed so that waste material being received on infeed conveyor 20 enters a controlled atmosphere environment for the entire process, until the material either enters an incinerator (see FIG. 14) or is discharged into a storage or transportation container or additional processing equipment (not shown).
The infeed and outfeed conveyors 20, 22 are substantially at ground level so that they may receive containerized hazardous material from forklifts, truck beds, rail cars and the like. However, the invention may include multiple infeed conveyors, arranged at multiple levels, and not depart from the scope of the invention. The infeed and outfeed conveyors 20, 22 include motorized conveyors 38, 40 adjacent to air locks 42, 44. The air locks 42, 44 communicate with the elevator 24.
The construction of air locks 42, 44 is substantially identical. Accordingly, the following description will be directed to air lock 42, it being understood that the description applies as well for air lock 44. Air lock 42 is totally enclosed by panels 46 which are attached to a frame 48, preferably by bolts (now shown) as shown in FIG. 2. The frame 48 also encloses a motorized conveyor 50 which extends between inner and outer air lock door assemblies 52, 54.
The following description will be directed to air lock door assembly 52, it being understood that the description applies to the construction of air lock door assembly 54 as well as the air lock door assemblies for air lock 44 of conveyor 22. As shown in FIGS. 3, 4, and 5, the air lock door assembly 52 includes plate-like inner and outer panels 56, 58, separated by a rectangular spacer 60, which includes a seal (not shown), such as an O-ring seal, on each side. However, other types or seals, such as caulking seals, may be used without departing from the scope of the invention. The panels 56, 58 and spacer 60 are sandwiched together and held in position by a ring of nut and bolt assemblies 62 (see FIG. 4). Inner and outer panels 56, 58 include rectangular openings 64, 66 which receive seal assemblies 68, 70, respectively. Seal assemblies 68,70 preferably are inflatable seals. As best shown in FIG. 5, gasket assemblies 68, 70 each include a retainer frame 72 and preferably a rectangular inflatable seal element 74.
As shown in FIG. 5, panels 56, 58 include pairs of vertical tracks 76, 78 which receive the vertically extending ribs 80, 82 of a door 84. The door 84 includes a longitudinal rack 86 which engages a pinion 88 driven by a hydraulic motor 90. The motor 90 is mounted on panel 58 and the pinion 88 is mounted on a shaft 92 which extends through an opening 94.
As shown in FIG. 1, when a reusable canister 96 is placed upon conveyor 38, the air lock door seals 74 are depressurized (see FIG. 5) and motor 90 actuated to rotate pinion 88. This causes the rack 86 and door 84 to be raised upwardly to open the passageway formed by openings 64, 66 to allow the motorized conveyor 38 to convey the canister 96 onto the conveyor 50 within the air lock 42.
As shown in FIG. 1, the elevator 24 is totally enclosed by panels 98 which are welded to a framework 100 shown in FIG. 6. The elevator 24 includes a hydraulic drive motor 102 which drives two sets of drive chains 104, 106 that are connected to a elevator platform 108 having driven rollers 110. The motorized rollers 110 are oriented to receive a canister 96 or other types of containerized waste from air lock 42. The discharger 26 is positioned at the top of the elevator 24 and intersects a dump chamber 112 that communicates with the drop chute 28 (see FIG. 1). The discharger 24 is totally enclosed by panels 114 which are welded to a framework 116. The framework 116 encloses ram member 118, positioned adjacent to elevator 24, and ram member 120.
As shown in FIG. 7, ram member 118 includes a ram carriage 122 which is supported on four ball screw rods 124, 126, 128, 130 by ball nuts 132. Motors 134 rotate the ball screw rods to displace the carriage 122 along the discharger 26 (see FIG. 6). Similarly, ram member 120 includes a ram carriage 136 which is supported on ball screw rods 138, 140, 142 by ball nuts 144. Ram member 120 is powered by a motor 146 which is connected to turn ball rod 138. Ball rods 138, 140, 142 are attached to joints 148, 150, 152, respectively, so that the rods 138-142 can rotate independently of rods 126-130, and ram member 120 is capable of moving independently of ram member 118.
As shown in FIG. 8, ram members 118, 120 include pivoting frames 154 which support gripper frames 156 for engaging canisters 96. The pivoting frames 154 each include longitudinal members 158 which are interconnected by transverse members 160. The longitudinal members 158 support slides 162 which are connected to the gripper frame 156, so that the gripper frame is slidable relative to the pivoting frame 154. The gripper frame 156 includes vertical struts 164 which slidably support segmented sleeves 165 having segments 166, 167 which are spanned by transverse struts 168, 169.
A bottom hook 170 is mounted on lower transverse strut 168 and hooks 172 are mounted on the outside of sleeve segments 167. Sleeves 166 are segmented so that transverse struts can be varied in vertical spacing, thereby varying the vertical spacing between hooks 172 and hook 170. Double-acting cylinder motor 174 spans the transverse struts 168, 169 of the pivoting frame and is actuated to move the hooks 172, 170 apart or toward each other to grip the canister 96. Lateral cylinder motors 176 are mounted on the pivoting frame 154 at one end and on the gripper frame 156 at an opposite end. Accordingly, the lateral of the cylinders 176 can be actuated to displace the gripper frame 156 relative to the pivoting frame 154.
A rear panel 178 is mounted on the pivoting frame 154 and supports a pivoting stud 180. Pivoting stud 180 is received within a bore 182 formed within support frame cross members 184. On ram member 118 only, a rotary actuator 186 is mounted which engages stud 180 and rotates pivoting frame 154. Pivoting frame 154 on ram member 120 pivots freely. Canister 96 includes bottom cut-outs 188 on opposing faces 190, 192 (only cut-out on face 190 is shown) which are shaped to receive the lower hooks 170 of the pivoting frames 154.
The action of discharger 26 is shown sequentially in FIGS. 9, 10, 11, and 12. The procedure begins with the elevator platform 108 being raised to the discharger 26. At this time, the ram members 118, 120 are in a retracted position. As shown in FIG. 10, motor 146 is actuated to drive rod 138 to advance ram carriage 136 to the container 96. Cylinders 176 on ram members 120 and ram member 118 are actuated to advance the gripper frames 156 toward the canister 96. When the gripper frames 156 are properly positioned, the cylinders 174 (see FIG. 8) are actuated to clamp the upper and lower hooks 170, 172 together, thereby engaging the canister 96 at both ends.
As shown in FIG. 11, the motors 134 and 146 have been actuated to displace ram member 118 to the drop chamber 112, and similarly, motor 146 has been actuated to retract ram member 120. The canister 96 is now positioned in the drop chamber 112. As shown in FIG. 12, the rotary actuator 186 is activated to rotate pivoting frame 154 to rotate canister 96 to a dump position. Pivoting frame 154 of ram member 120, which pivots freely, is also rotated. The rotary actuator is adjusted to rotate the canister 96 through 180 so that all of the contents are dumped in the drop zone. Once the dumping action has been completed, the rotary actuator 186 rotates the gripper frames 154 to an upright position, as shown in FIG. 11, and the two ram members 118, 120 are displaced sidewardly to the configuration shown in FIG. 10. The cylinders 174 are actuated to disengage the upper and lower hooks 172, 170 from the canister 96, and the cylinders 176 actuated to displace the gripper frames 156 from the canister 96. At this time, the canister 96 is resting upon the elevator platform 108 (see FIG. 9).
The ram member 120 is displaced sidewardly away from the canister 96 to the position shown in FIG. 9, and the elevator 24 (see FIG. 6) actuated to lower the canister 96 to where it is level with air locks 42, 44. The air lock door 54 is opened and the conveyor 110 actuated to displace the empty canister to within the outfeed air lock 44, where it is received by powered rollers 50. The outfeed air lock door 54 closes, the outfeed air lock 42 is purged and door 52 opens to allow the canister 96 to be displaced sidewardly to outlet conveyor 40.
As shown in FIG. 13, if disposable containers, such as 55 gallon drums 190 supported by a pallet 192 are to be disposed of, ram member 120 is not actuated. Rather, ram member 118 is actuated to displace the pallet 192 and container 190 sidewardly to the drop zone 112. For this type of waste, the gripper frame 156 of the ram member 118 is not displaced forwardly since the hooks are not used to engage the container.
As shown in FIG. 14, the drop zone 112 is enclosed within a drop chute 28 having explosion doors 129. Drop chute 28 which feeds a dual auger 30 having a pair of opposing, tapered auger screws 194. The dual auger 30 also includes a pair of doors 196 which control the residence time of waste material within the dual auger compartment.
The single auger 32 includes a single auger screw 198 which receives shredder material from the dual auger 30 and further reduces and compresses it, and pumps it through an outlet, extrusion tube 200. The extrusion tube 200 is connected to a an injector auger 34 which pumps the material into a rotary reactor 202. Injector auger 34 also could pump material into a container or additional processing or conveying equipment (not shown), such as a ball mill, without departing from the scope of the invention. As shown in FIGS. 1 and 14, a rotary gate 204 is positioned between the injector 34 and reactor 202, and can be opened and closed to prevent burn-back or escape of material. The dual auger 30 preferably has the construction of the dual auger disclosed in Koenig U.S. Pat. No. 4,938,426. The single auger 32 preferably has the construction shown in Koenig U.S. Pat. No. 4,951,884, and the injector mechanism preferably has the structure shown in Koenig U.S. Pat. No. 4,915,308, the disclosures of these patents being incorporated herein by reference. Further, the rotary door structure is disclosed in Koenig U.S. Pat. No. 632,766, filed Dec. 21, 1990, the disclosure of which is incorporated herein by reference.
As shown in FIGS. 15, 16, and 17, the slide box 36 includes a housing 206 having a front wall 208, a rear wall 210 and transverse support members 212, 214, 216, 218. A flange 220 is mounted on front wall 208 and is connected to the injector auger 34 (see FIGS. 1 and 14). Rear wall 210 includes outlet flange 222 which is connected to a feed conduit 224 (see FIG. 1) that is connected to the reactor 202.
A forward frame 225 is mounted against the front wall 208 and a rearward frame 226 is mounted against the rear wall 210. The forward frame 224 forms a space 228 which receives a forward slide plate 230. Similarly, rear frame 226 forms a space 232 with rear wall 210 and receives rear slide plate 234. A through conduit 236 extends between forward and rearward slide plates 230, 234, and a diverter conduit 238 extends between forward and rearward slide plates 230, 234. The slide plates 230, 234 are positionable within slots 228, 232 such that alternately, conduit segment 236 or conduit segment 238 are in registry with flange 220.
Forward and rearward slide plates 230, 234 include upwardly extending bosses 240, 242 which are attached to double-acting cylinder motors 244, 246 that are anchored on angle stops 248, 250 mounted on longitudinal angles 214. Accordingly, the cylinder motors 244, 246 are selectively positionable to displace the forward and rearward slide plates 230, 234, thereby positioning the conduit segments 236, 238 in registry with flange 220, and in the case of conduit segment 236, in registry with flange 222.
As shown best in FIG. 17, conduit segment 238 includes a substantially rectangular bottom opening 252 and a diverter plate 254 which acts to deflect incoming material downwardly through the bottom opening 252.
As shown best in FIG. 16, inlet and outlet flanges 220, 222 include annular gaskets 256, 258. Conduit segment 236 includes front and rear gasket elements 260, 262 which form an air-tight seal with gaskets 256, 258, respectively, when the conduit segment 236 is in registry with flanges 220, 222. Similarly, segment 238 includes gasket 264 which forms an air-tight seal with gasket 256 when these front and rear slide plates 230, 234 are displaced to place conduit segment 238 in registry with flange 220.
All of the hydraulic motors and hydraulic cylinder motors of the waste processing system shown in FIGS. 1-17 are controlled by a single programmable logic controller. As shown in FIG. 18, programmable logic controller 256 receives a signal from pressure sensor 258 when canister 96 is placed upon motorized conveyor 38. Valve 260 is actuated to activate the outer door motor 90 to raise the outer door 84 of air lock door assembly 52 of air lock 42. Valve 262 is actuated to activate the infeed conveyor 38 to displace the canister 96 through the opening in the air lock door 52 into the air lock 42. Simultaneously, the valve 264 is actuated by controller 256 to energize the conveyor 50 to receive the container 96 and displace it to the interior of the air lock 42. Valve 260 is again actuated to lower the door of the outer air lock assembly 52, and valve 266 actuated to pressurize the seals to secure the outer door assembly 52. A photoeye 268 senses the presence of the canister 96 within the air lock 42 and the controller 256 actuates the valves 266, 264 to stop the conveyors 38, 50. Proximity switches 270 located on outer door assembly 52 determine the displacement range for the door 84 within the outer air lock door 52. Alternately, a resolver may be used to determine the position of the door.
At this time, valve 272 is actuated to depressurize the seals of the inner air lock door 54. Proximity switch 274 indicates that the elevator platform 108 is in the down position so that the platform is level with the conveyor 50. A photo-eye 276 within the elevator shaft senses that the elevator platform 108 is empty, and valves 264 and 278 are actuated to displace the canister 96 from the air lock 42 onto the elevator platform 108. Valve 280 is actuated to lower the inner air lock door 54 and valve 272 actuated to pressurize the seals on that door. Valve 282 is actuated to energize the motor 102 of the elevator to raise the platform 108 to the discharger 26.
A proximity switch 284 is tripped when the elevator platform 108 reaches the discharger 26 and the controller 256 actuates motor valve 282 to stop the elevator. A photoeye 286 in the discharger detects the presence of a canister (as opposed to waste material contained in disposable containers such as drums), and the ram members 118, 120 are actuated in a sequence described with reference to FIG. 19. When the empty canister 96 is returned to the elevator platform 108 and is lowered to ground level, proximity switch 274 indicates that platform 108 is at the proper level. Valve 272 is actuated to depressurize the seals on door 54 and valve 280 actuated to raise the door. Valves 262, 264 are actuated to displace the container 96 sidewardly into the outfeed air lock 44, and door 54 is shut and sealed.
Valve 288 is actuated to purge the volume within air lock 42 with gas so that the contaminated air is driven into a charcoal canister or alternately, to the reactor 202. When the purge has been completed, valve 266 is actuated to de-pressurize seals on door 52 and valve 260 actuated to open the outer door. Valves 266 and 264 are actuated to displace the container 96 outwardly to be collected.
The arrangement of valves and sensors for air lock 44 is the same as for air lock 42. Specifically, controller 256 actuates valves which control the pressurization of seals for doors 52, 54 of air lock 44 and for the motorized conveyors 40 and 50 of air lock 44.
Valve 294 actuates the cylinders 176 on pivoting frame 154 of ram member 118 to displace the hooks 172, 170 forwardly, and valve 296 is actuated to clamp the hooks together to engage the canister 96.
Valve 298 actuates motor 146 to displace the ram member 120 sidewardly until proximity switch 300 is tripped, indicating that the ram member 120 is snug against the container 96. Valve 302 is actuated to energize cylinder motors 176 on pivoting frame 156 of ram member 120 to advance the hooks 170, 172 forwardly. Valve 304 is actuated to activate cylinder 174 to clamp the hooks 170, 172 against the container.
Valves 290 and 298 are again actuated to activate motors 134, 146 to displace the container 96 sidewardly to the drop zone 112. Proximity switch 306 is tripped when the container is properly positioned. Valve 308 is actuated to activate the rotary actuator 186 to rotate the pivoting frame 154 of ram member 118, and consequently, pivoting frame 154 of ram member 120, to dump the container 96. Proximity switch 310 is tripped when the container has been inverted 180 degrees.
The controller 256 then actuates valve 308 to rotate the container 96 back to an upright position and the valves 290, 298 actuated to displace the container 96 sidewardly to the position shown in FIG. 6. A proximity switch 312 indicates when the ram members 118, 120 are properly positioned. Valves 302, 304 are actuated to reposition the fingers 170, 172 away from engagement with container 96, and valve 298 actuated to activate motor 146 to displace ram member 120 sidewardly to the position shown in FIG. 6. A proximity switch 314 is tripped when the ram member 120 is properly positioned.
In addition to the foregoing sensors and valves, the programmable logic controller system also includes an oxygen sensor 316 and preferably includes a pressure sensor 318 to detect a predetermined gas pressure within the system of the present invention so that it may be maintained at a predetermined value. Valves 320, 322 are actuated to release an inert gas, such as nitrogen, or to depressurize the system. Further a mercury sensor 324 preferably is placed in the dual auger shredder 30, and the presence of mercury causes controller 256 to actuate valve 326 to activate cylinder motors 244, 246 of slide box 36 to position conduit segment 238 in line with flange 220 (FIG. 15) to divert mercury-contaminated waste from reactor 202. However, such sensors are well-known in the art and therefore are not illustrated here.
The system of the present invention may be adapted to suit a particular configuration of incinerator or other waste handling device. Accordingly, other geometries comprising the infeed conveyor, elevator, discharger, drop, and augers may be employed without departing from the scope of the invention.
For example, as shown in FIG. 20, the system of the present invention is utilized in combination with a kiln 202 having an infeed chute 330 which is at an elevation above that of the infeed conveyor 20. Consequently, the single auger 32 is elevated from the ground and supported on a frame 332 so that the injector auger 34 and feed tube 224 are elevated to feed into the infeed chute 330. Also, the entire waste processing system may be offset from the face 334 of the rotary reactor 202 in order to allow clearance for other feeding equipment and fuel input.
As shown in FIG. 21, the waste processing system may be utilized in combination with a sag mill, generally designated 336. In this embodiment, the single auger 32 discharges material through the extrusion tube 200 into a modified injector auger 34'. Injector auger 34' includes a feed tube 224' which is inclined upwardly to the infeed plenum 338 of the sag mill. Consequently, although the single auger 32 is at the same level as the inlet to the elevator 24, the system may feed a device whose inlet is substantially above ground level.
As shown in FIG. 22, the waste processing system of the present invention may be utilized with a rotary kiln 202 having a face 344 which is connected to the feed tube 224 of the injector auger 34. The injector 34 and feed tube 224 is substantially horizontal with respect to the rotary kiln 202, and is at a higher elevation than the infeed and outfeed conveyors 20, 22 respectively.
As shown in FIG. 23, the waste processing system of the present invention may utilize a second infeed conveyor 20', having a second infeed airlock 42' with inner and outer doors 52', 54', respectively, which is connected to elevator 24'. Second infeed conveyor 20' is located at an elevation above that of infeed conveyor 20, preferably on a floor above the floor supporting conveyor 20 (which may be at ground level or below). Second infeed conveyor 20' includes a motorized conveyor 38' for supplying containerized or palletized material to the conveyor, which conveys the material to elevator platform 108 (see FIG. 6). Consequently, the system of FIG. 23 can receive material from multiple locations at multiple elevations.
While the form of apparatus herein described constitutes a preferred embodiment of this invention, it is to be understood that the invention is not limited to this precise form of apparatus, and that changes may be made therein without departing from the scope of the invention. | A waste processing system in which containerized waste is received substantially at ground level and is conveyed to an elevator which carries the containerized waste to an upper level discharger which transports the containerized waste, dumps the containers down a drop chute and returns the empty containers to ground level. The dumped waste is shredded and is either injected into an incinerator or is discharged downwardly. The entire system is enclosed and can be maintained at either a negative or positive pressure for receiving radioactive or hazardous wastes, or at a reduced oxygen environment for receiving flammable hazardous waste. Containerized waste is received through air locks which include sliding doors that are supported entirely about the peripheries when sealed for purposes of explosion resistance. The injector discharge tube includes a slide box in which a pair of conduit segments are mounted and can be positioned such that one or the other of the segments is connected to the output conduit. One segment connects the output conduit to an incinerator or other receiver and the other segment includes an open bottom so that material may drop vertically into a receptacle. | 8 |
CONTINUITY DATA
This application is a continuation of application Ser. No. 14/282,280 filed May 20, 2014 which is a continuation of application Ser. No. 14/090,385 filed Nov. 26, 2013, (now issued as U.S. Pat. No. 8,776,131); which is a continuation of application Ser. No. 13/940,992 filed Jul. 12, 2013, (now issued as U.S. Pat. No. 8,782,708); which is a continuation of Ser. No. 13/837,094 filed Mar. 15, 2013 (now abandoned); which is a continuation of Ser. No. 13/614,306 filed Sep. 13, 2012 (now issued as U.S. Pat. No. 8,443,391); which is a continuation of Ser. No. 13/099,856 filed on May 3, 2011 (now issued as U.S. Pat. No. 8,347,335); which is a continuation of application Ser. No. 12/776,063 filed on May 7, 2010 (now issued as U.S. Pat. No. 7,962,939); which is a continuation of application Ser. No. 12/222,588 filed on Aug. 12, 2008 (now issued as U.S. Pat. No. 7,761,895); which is a continuation of application Ser. No. 11/075,928 filed on Mar. 10, 2005 (now issued as U.S. Pat. No. 7,426,742), which is a continuation of application Ser. No. 09/828,865 filed on Apr. 10, 2001 (now issued as U.S. Pat. No. 7,424,729); which claims the benefit of provisional application no. 60/197,677 filed on Apr. 17, 2000, all the applications which are incorporated herein by reference in its entirety.
FIELD OF THE INVENTION
The invention is directed toward the field of digital television signal meta data generation, and more particularly to the non-uniform issuance of certain tables included within such meta data.
BACKGROUND OF THE INVENTION
It is known for a digital television (DTV) signal to include meta data representing information about the contents of the events, e.g., programs, movies, sports games, etc. contained in the DTV signal. For a terrestrially broadcast DTV signal, the Advanced Television Standards Committee (ATSC) has promulgated the A/65 Standard that defines such meta data. The A/65 standard refers to such meta data as program and system information protocol (PSIP) data.
The PSIP type of meta data is issued periodically. Data of greater importance in the meta data hierarchy is inserted into the DTV signal more frequently than data of lower importance.
In general, in this art it is desired to maximize the amount of available bandwidth that can be allocated to the transmission of the DTV program content. Unfortunately, meta data consumes bandwidth that otherwise could be used to transmit the corresponding DTV program content. But such meta data is a prerequisite to an A/65 compliant DTV signal, hence it cannot be eliminated to recover bandwidth.
It is a problem to reconcile the contradictory design criteria of maximizing bandwidth allocated to DTV program content and providing sufficient meta data to ensure compliance with the A/65 standard.
SUMMARY OF THE INVENTION
The invention is, in part, a solution to the problem of how to insert the least amount possible of meta data into the DTV signal and yet still achieve an A/65 compliant DTV signal. In other words, the invention is, in part, a recognition that it is desirable to insert meta data into the DTV signal as infrequently as possible.
The invention is, also in part, a recognition that: the A/65 standard establishes fixed frequencies of table output for some of the program and system information protocol (PSIP) data tables, e.g., such as the Master Guide Table (MGT), the Virtual Channel Table (VCT) and the System Time Table (STT), but not for some others; and such unfixed output intervals afford opportunities to lessen meta data output thereby reducing bandwidth consumption in the form of PSIP meta data without sacrificing compliance with the A/65 standard.
The invention provides, in part, a method to determine issuance intervals for like types of tables, respectively, in a digital television packet stream having a plurality of different types of tables that do not have issuance intervals set by a governing standard. Such a method comprises: setting issuance intervals for like ones of the non-governed tables, respectively, to be non-uniform. Such non-uniform issuance intervals can be determined as a function of at least one of an amount of time in the future to which the table corresponds and a degree of probable interest to a viewer. Further, such non-uniform issuance intervals can be weighted so that an issuance interval for a table corresponding to a time nearer the present is smaller than an issuance interval corresponding to a time further in the future.
Examples of meta data PSIP tables that can benefit from the method according to the invention include extended text tables (ETTs) and event information tables (EITs).
Each issuance interval between any two instances of an i th table can be determined according to the following equation:
interval( i th table)=root_time+(increment_time)* i
where interval(i th table) is the interval between any two instances of the i th table, root_time is a predetermined interval for the table corresponding most closely in time to the present, increment_time is a non-zero scalar and i is a non-zero integer.
The invention, also in part, provides a program and system information protocol (PSIP) generator to generate tables for a digital television system packet stream, the generator comprising: an interface to receive at least one issuance parameter for like tables that do not all have an issue interval assigned by a governing standard; and a non-uniform interval calculation unit to determine non-uniform issuance intervals for unassigned-interval-ones of said like tables based upon said at least one issuance parameter. Such a PSIP generator embodies the method according to the invention, e.g., as described herein.
The invention, also in part, provides a processor-readable article of manufacture having embodied thereon software comprising a plurality of code segments to cause a processor to perform the method according to the invention.
According to an aspect of the invention, there is provided an apparatus for generating at least one table in a broadcast environment, the apparatus comprising: a generator to generate an event information table (EIT) and an extended text table (ETT), the ETT having program guide information for an n-hour span and having a transmission interval, the ETT having a transmission interval and having program description information according to the EIT, wherein the transmission interval of the EIT is shorter than the transmission interval of the ETT.
According to an aspect of the invention, there is provided a method for generating at least one table in a broadcast environment, the method comprising: generating an event information table (EIT) and an extended text table (ETT), the ETT having program guide information for an n-hour span and having a transmission interval, the ETT having a transmission interval and having program description information according to the EIT, wherein the transmission interval of the EIT is shorter than the transmission interval of the ETT.
According to an aspect of the invention, there is provided a data structure for generating at least one table in a broadcast environment, the structure comprising: an event information table (EIT) having program guide information for an n-hour span and having a transmission interval; and an extended text table (ETT) having a transmission interval and having program description information according to the EIT, wherein the transmission interval of the EIT is shorter than the transmission interval of the ETT.
Advantages of the present invention will become more apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus do not limit the present invention.
FIG. 1 is a block diagram of a PSIP generator according to the invention in the context of typical inputs to it and outputs from it.
FIG. 2 is an image of a dialog window within a screen of a graphical user interface (GUI) generated by the PSIP data generator according to the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 is a block diagram of a program and system information protocol (PSIP) data generator according to the invention in the context of system 100 that can produce an Advanced Television Standards Committee (ATSC), standard A/65, compliant digital television (DTV) signal. The system 100 of FIG. 1 includes: a PSIP generator 102 according to the invention; sources of data upon which the PSIP generator operates, such as a source 108 of listing service data, a source 110 of traffic system data and a source 112 of other data; a multiplexer 114 to incorporate the PSIP data from the PSIP generator 102 into an A/65-compliant DTV signal; and a source 116 of audio data, video data, etc.
In FIG. 1 , the PSIP generator 102 includes an interface unit 104 and a non-uniform interval calculation unit 106 .
The PSIP generator 102 according to the invention can be implemented by adapting a well known PSIP generator according to the discussion herein. An example of a known PSIP generator is the PSIP BUILDER PRO brand of PSIP generator manufactured and sold by TRIVENI DIGITAL INC. The PSIP BUILDER PRO itself is based upon a programmed PC having a Pentium type of processor using the MICROSOFT WINDOWS NT4.0 operating system. The software can be written in the Java language. The other blocks of FIG. 1 correspond to known technology.
In FIG. 1 , the invention has been depicted in the context of a digital television broadcast such as a terrestrial broadcast, and more particularly one that is compliant with the Advanced Television Standards Committee (ATSC), where each event is a program, and the schedule data is PSIP data. However, the invention is readily applicable to any television format, e.g., analog terrestrial, analog cable, digital cable, satellite, etc., for which an electronic schedule is maintained and corresponding data is sent to a receiver for the purpose of presenting an electronic program guide (EPG) to a viewer.
The units 104 and 106 within the PSIP generator 102 do not necessarily correspond to discrete hardware units. Rather, the units 102 and 104 can represent functional units corresponding to program segments of the software that can embody the invention.
The interface unit 104 can generate a graphical user interface (GUI) that operates to receive at least one issuance parameter for like PSIP tables (e.g., ETTs or EITs) that do not all have an issue interval assigned by the A/65 standard. Such an interface will be described in more detail below with regard to FIG. 2 . The non-uniform interval calculation unit 106 is operable to determine non-uniform issuance intervals for ones of the like PSIP tables that do not have an assigned interval, based upon the issuance parameter(s) received via the interface unit 104 .
FIG. 2 is an example image of a dialog window 200 (a GUI) that can be generated by the interface unit 104 according to the invention. In FIG. 2 , the dialog window 200 can include: a Cycle Time Settings tab 202 ; a Miscellaneous Settings tab 204 ; a FTP Periodic Update Controls tab 206 ; an “Apply Settings” button 226 ; a “Defaults” button 228 ; a “Refresh” button 230 ; and a “Close” button 232 . The position of the cursor can be indicated via the reverse highlighting 234 . The Cycle Time Settings tab 202 can include a “Cycle Times (in seconds) for EITs:” region 208 , a “Cycle Times (in seconds) for PSIP Tables:” region 210 , a “Cycle Times (in seconds) for PSI Tables:” region 212 and a “Cycle Times (in seconds) for ETTs:” region 214 .
It is well known that EITs carry program schedule information including program title information and program start information. Each EIT covers a three-hour time span. ETTs carry text messages associated with the EITs, e.g., program description information for an EIT.
In FIG. 2 , the “Cycle Times (in seconds) for EITs:” region 208 of the dialog window 200 can include: a box 216 in which a user can enter a fixed interval for the EIT 0 table; a box 218 in which a user can enter an increment for the EIT k table; and a box 220 in which a user can enter a maximum number of EIT tables that are to be sent. Usually, the number entered in box 220 will be far smaller than the maximum number of EIT tables permitted by the A/65 standard.
Also, in FIG. 2 , the “Cycle Times (in seconds) for ETTs:” region 214 can include: a box 222 in which a user can enter a fixed interval for the ETT 0 table; and a box 224 in which a user can enter an increment for the ETT k table.
The non-uniform interval calculation unit 106 can receive the values in the boxes 216 , 218 , 220 , 222 and 224 from the regions 208 and 214 , respectively, and use them to determine the non-uniform issuance intervals of, e.g., the EIT and ETT tables. Further discussion of the operation of the unit 106 is couched in a particular non-limiting example, for simplicity.
The A/65 standard recommends a time interval for outputting the zeroith Event Information Table (EIT), i.e., EIT 0 , but provides no guidelines regarding EIT 1 through EIT 128 . For the Rating Region Table (RRT), the A/65 standard recommends a value only for the output frequency of RRT 1 . And no recommendation is made regarding the output frequencies of any of the Extended Text Tables (ETTs).
Under the A/65 standard, it is left to the discretion of the operator of a PSIP data generation system to select the frequency of table output for the unmentioned tables. The operator could specify an entry for each group of tables, but that would be burdensome because it would require a total of over 500 entries. A simple solution to the problem of unspecified output frequencies would be to set each type of table to the same output frequency, but that creates a problem in that the guidelines for bandwidth specified by the A/65 standard would be exceeded.
A further consideration to solve the problem, namely of how to insert the least amount possible of meta data into the DTV signal and yet still achieve an A/65 compliant DTV signal, is: How closely in time to the present moment does each table relate? That is, table types such as the EIT describe event information up to two weeks into the future. A user of an electronic program guide that receives such table types will typically want to view event information concerning only the next 24-48 hours. Users typically do not look farther into the future than this because (at least in part) the event schedule information two weeks into the future is much more likely to change than is event schedule information concerning the next 24-48 hours, i.e., the farther into the future, the less reliable the event information becomes.
Care must be exercised so as not to set the intervals to be too infrequent. This is because the DTV receiver can become stalled waiting for a table to arrive. If the DTV receiver is stalled for 0.5 seconds, a user might not notice or object if she did. But such a delay of, e.g., 4-5 seconds probably would be noticed by, and probably would annoy, the user. This reinforces the need to set short intervals for near term events because users are likely to want to display EPG information about them.
Again, the invention, in part, provides an interface unit 104 that defines parameters that the non-uniform interval calculation unit 106 then can use to generate the time intervals between tables of the same type. Typically (but not necessarily) the function performed by the unit 106 will be linear, e.g., with a defined start interval (the root_time) and an increment interval (increment_time). For example, if the user desires EIT 0 to be output every half second (root_time) with each succeeding EIT i to be output 0.25 seconds less frequently than the preceding EIT, namely EIT i-1 , the user would enter 0.5 seconds as the root_time in box 216 and 0.25 seconds as the increment_time in box 218 . The function for each table EIT-i interval would then be:
Time between any two instances of table i = root_time + ( increment_time * i ) = 0.5 sec + ( 0.25 sec * i )
For example, EIT 12 can be output every 0.5 sec+(0.25 sec*12)=3.5 seconds, which is less frequent than EIT 0 . Obviously, other examples are possible, e.g., the increment_time for each of different groups of like tables can be set.
A similar calculation for ETTs can be performed by the unit 106 .
The invention has at least the following advantages: 1) it provides an easy way of entering the interval times for the tables: 2) it defines the interval times for like tables that are not all fixed to a constant interval; and 3) it provides an interval function that increases the interval for tables that represent information further out in time.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims. | An apparatus, method and data structure for generating at least one table in a broadcast environment, are provided. The apparatus includes a generator to generate an event information table (EIT) and an extended text table (ETT). The ETT has program guide information for an n-hour span and has a transmission interval. The ETT has a transmission interval and program description information according to the EIT. The transmission interval of the EIT is shorter than the transmission interval of the ETT. | 7 |
CROSS REFERENCE TO RELATED APPLICATION
This application is a national phase of PCT/HU90/00026 filed Apr. 18, 1990.
FIELD OF THE INVENTION
The invention relates to an improved, large scale process for the preparation of ketones of formula (I) ##STR2## wherein R is halogen atom or hydroxyl,
R 2 is hydrogen atom or hydroxyl,
R 3 and R 4 are hydrogen atom or alkoxy having 1-6 carbon atoms.
BACKGROUND OF THE INVENTION
It is known that the ketones of formula (I) can be used as intermediates for the preparation of isoflavone derivatives (see e.g. HU PS No. 163,515) as well as anabolics since they effect metabolism.
From an industrial point of view those processes are the most advantageous wherein resorcinol is used as starting material, e.g. the desired product may be obtained according to the Houben-Hoesch reaction: wherein the resorcinol is reacted in anhydrous medium with benzyl cyanide in the presence of dry hydrogen chloride gas and anhydrous tin chloride (see e.g. J. Chem. Soc. /1923/, 404 and J. Am. Chem. Soc. 48, 1926, 791). The yield in this reaction is 50% and the drawback of this process is that the hydrolysis of the "ketimine" derivate intermediate is a very corrosive procedure.
Alternatively 2-hydroxy-4-n-butoxy-phenyl-benzyl ketone or 4-hydroxy-2-n-butoxy-phenyl-benzyl ketone may be obtained when reacting the mono-n-butyl ether of resorcinol with phenyl-acetyl-chloride in the presence of pyridine, then removing pyridine by distillation, dissolving the residue in ether, extracting the solution with hydrogen chloride several times, removing the ether by distillation, thereafter treating the 1-phenyl-acetyloxy-4-n-butyloxy-phenol thus obtained in nitrobenzene with aluminum chloride and steam distilling the mixture thus obtained (see Example 7 of HU PS No. 168,744). The starting material of the first step, i.e. the mono-n-butyl ether of resorcinol, can be obtained e.g. when reacting resorcinol with n-butyl bromide in the presence of dimethyl formamide. Regarding that from resorcinol diether derivatives may also be formed, in order to obtain an end product of good quality, the monoethers have to be purified before the second reaction step.
The analogous phenol compound can be prepared by the known, so called Bouveault reaction too, wherein 2 moles of anhyrous aluminium chloride are reacted with phenol. In the first step of this reaction phenoxy-aluminium dichloride forms while hydrogen chloride gas is released. In the second reaction step said phenoxy-aluminium dichloride is then reacted with the acid chloride derivative in the presence of a further mole of aluminium chloride (Olah, Gy:Friedel Crafts and related reactions, Vol. I, page 97, 1963).
The drawbacks of these known processes are as follows:
the reaction procedure itself and the technology too, are rather difficult,
large amounts of aluminum chloride (2 moles) is required,
the released hydrogen chloride is corrosive.
DESCRIPTION OF THE INVENTION
The present invention relates to a process for the preparation of ketones of formula (I) and salts thereof ##STR3## wherein R, R 2 , R 3 , R 4 , R 6 are the same as mentioned above wherein phenols of formula (II) ##STR4## are reacted with acid chlorides of the formula (IV) ##STR5## in the presence of inert, anhydrous organic solvent and anhydrous aluminum chloride by a method known per se, the mixture thus obtained is decomposed with an aqueous acid solution and the phases obtained are separated. According to the invention the phenol derivative is reacted with 1 mole aluminum chloride--calculated for the phenol derivative--at a temperature between 0° C. and 40° C. in the presence of halogenated hydrocarbon, preferably dichloroethane. Thereafter the complex of the formula (III) thus obtained ##STR6## is reacted with an acid chloride of the formula (IV) ##STR7## preferably in the presence of the solvent used previously at a temperature ranging from 10° C. to 60° C., thereafter adding an aqueous acid solution to the mixture thus obtained, separating the phases and recovering the desired ketone compound from the organic layer.
We have surprisingly discovered that when reacting e.g. resorcinol with 1 mole of anhydrous aluminum chloride, without hydrogen chloride formation a hydrogen-aluminum-trichloro-3-hydroxy phenolate (referred to hereinafter simply as "complex") is obtained, which dissolves in the reaction medium used. This complex is very active and it is able to react with the acid chloride without adding additional aluminum chloride.
The process of the invention is based on the above recognition and phenol derivatives of formula (II) are used as starting material.
In the process according to the invention halogenated hydrocarbons, preferably dichloroethane, are used as solvent in 3 to 10-fold excess. The reaction temperature depends on the used starting material; in the case of resorcinol and dichloroethane the reaction is preferably carried out at a temperature of 10° to 25° C.
The reaction of the complex with the acid chloride can be carried out by adding the aromatic acid chloride or the solution thereof to the solution or to the suspension of the complex or alternatively the solution or suspension of the complex can be added to the acid chloride or to the solution of same.
In a preferred embodiment of the process according to the invention the preparation of the complex and the subsequent reaction steps are carried out in the same aprotic solvent, preferably in halogenated hydrocarbons.
Another important recognition of the present invention enables the pure isolation of the desired product. We have found that the ketones of the formula (I), which are obtained from the resorcinol derivatives of the formula (V) ##STR8## wherein R 6 is hydrogen atom or hydroxyl can react with potassium carbonate to form the double salts of formula (VI) ##STR9## wherein R 3 , R 4 and R 6 are the same as mentioned above which are not soluble in aprotic solvents. So, according to a preferred embodiment of the process according to the present invention, the product is isolated (e.g. separated by filtration) in the form of this salt and so can selectively be separated from the side products or other accompanying materials which are present or are formed in the reaction mixture. The ketone of formula (I) can be obtained from the double salt of formula (VI) after dissolving it in water and acidifying the solution thus obtained to pH=3.5-4.5.
The above mentioned step is especially preferred if the starting resorcinol or acid chloride are not sufficiently pure. When pure starting material is used, ketones of appropriate quality can be obtained by the optional removal of the solvent of the organic layer and by recrystallization, preferably from toluene, of the residue.
The advantages of the present invention are e.g. as follows:
the synthesis can be carried out without the separation of the intermediates, especially without the preparation of the mono-n-butyl ether of resorcinol and without the use of nitromethane, nitrobenzene or ether solvents,
the amount of the aluminium chloride is decreased to the half of the amount used in the known processes,
the considerable corrosion of the Houben-Hoesch method can be eliminated,
the yield amounts to 82-85%, which is substantially higher than that of any known method,
the quality of the product is very good.
SPECIFIC EXAMPLES
The process according to the invention is illustrated in detail by the following Examples.
EXAMPLE 1
55 g (0.5 mole) of resorcinol were suspended in 250 ml of dichloro ethane and at 20° C. 67 g (0.502 mole) of anhydrous aluminum chloride were added. To the obtained homogeneous dark solution, containing the hydrogen-aluminum-trichloro-3-hydroxy-phenolate, 77.2 g (0.5 mole) of phenyl-acetyl chloride in 100 ml of dichloro ethane were added over one hour while the temperature raised to 35°-40° C. The reaction mixture was stirred for one hour, the solution thus obtained was added to an aqueous hydrochloric acid solution, the two layers were separated, the organic layer was washed with water to neutral, the solvent was distilled off and the residue was optionally crystallized from toluene. 96.9 g of 2,4-dihydroxy-phenyl-benzyl-ketone were obtained, m.p.: 112°-114° C., yield: 85%. After an optional recrystallization from toluene the melting point was 113°-114° C. Elemental analysis for C 14 H 12 O 3 (Mw: 228):
Calculated: C %: 73.68, H %: 5.26. Found: C %: 73.6, H %: 5.3.
NMR spectrum (Bruker WP 80 spectrometer, in DMSO-D 6 solvent, TMS internal standard):
______________________________________ .sup.1 H 6 C--H 7.90 ppm /d/ .sup.3 J-9Hz 5 C--H 6.37 ppm /dd/ 3 C--H 6.25 ppm /d/ .sup.4 J-2Hz .sup.13 C 4-C 165.1 ppm______________________________________
Example 2
The procedure described in Example 1 was followed. After separating the two phase mixture, the organic layer was washed to neutral with water, the dichloroethane layer was separated and 69 g (0.5 mole) of anhydrous potassium carbonate were added. From the reaction mixture the precipitated 2,4-dihydroxy-phenyl-benzyl-ketone-potassium-potassium hydrogencarbonate double salt (C 14 H 11 O 3 K.KHCO 3 ) was separated by filtration (166 g), was dissolved in methanol:water=1:3 and the solution thus obtained was acidified (pH=4) with 33% acetic acid. The precipitated product was filtered and after drying 96.2 g of 2,4-dihydroxy-phenyl-benzyl-ketone were obtained, m.p. 113°-114° C. The quality of the product thus obtained was identical with the product of Example 1 obtained after recrystallization. The melting point of a mixture (1:1) did not show depression.
Elemental analysis for C 14 H 11 O 3 K.KHCO 3 (Mw:366): Calculated: C %: 49.18, H %: 3.27. Found: C %: 49.6 H %: 3.32.
______________________________________NMR spectrum:______________________________________ .sup.1 H 6 C--H 7.63 ppm /d/ .sup.3 J= 9Hz 5 C--H 6.00 ppm /dd/ 3 C--H 5.78 ppm /d/ .sup.4 J= 2Hz .sup.13 C 4-C 174.2 ppm______________________________________
The potassium salt in the double salt of 2,4-dihydroxy-phenyl-benzyl ketone appears in the 4-position.
EXAMPLE 3
64.25 g (0.5 mole) of 2-chlorophenol were dissolved in 200 ml of dichloroethane and 67 g (0.5 mole) of anhydrous aluminum chloride were added to the solution. Thereafter 77.2 g (0.5 mole) of phenyl-acetyl chloride in 100 ml of dichloroethane were added over 1 hour under stirring while the reaction temperature raised from 15°-20° C. to 35°-40° C. After a one-hour stirring the reaction mixture was admixed with aqueous hydrogen chloride, the two-phase mixture was separated, the organic layer was washed with water to neutral and the solvent was removed. 106.1 g of 2-hydroxy-3-chloro-phenyl-benzyl-ketone were obtained, m.p.: 62°-64° C. After a recrystallization from aqueous isopropanol (1:2), m.p. 63°-67° C.
Elemental analysis for C 14 H 11 ClO 2 (Mw:246.5): Calculated: C %: 68.15, H %: 4.46, Cl %: 14.40. Found: C %: 68.55, H %: 4.70, Cl %: 14.00.
Example 4
22 g (0.2 mole) of hydroquinone were dissolved in 60 ml of dichloroethane and 26.8 g (0.2 mole) of anhydrous aluminum chloride were added to the solution. To the obtained complex 30.8 g (0.2 mole) of phenyl-acetyl chloride in 30 ml of dichloroethane were added. Further the procedure of Example 1 was followed. 10.1 g of 2,5-dihydroxy-phenyl-benzyl-ketone were obtained, m.p.: 118°-120° C.
Elemental analysis for C 14 H 12 O 3 (Mw: 228): Calculated: C %: 73.68, H %: 5.26. Found: C %: 73.62, H %: 5.58.
EXAMPLE 5
24.7 g (0.196 mole) of floroglucinol were dissolved in 70 ml of dichloroethane and 26.6 g (0.2 mole) of anhydrous aluminum chloride were added to the solution. To the obtained complex 30.1 g (0.196 mole) phenyl-acetyl-chloride in 30 ml of dichloroethane were added. Further the procedure of Example 1 was followed.
15 g of 2,4,6-trihydroxy-phenyl-benzyl-ketone were obtained, m.p.: 117°-120° C.
Elemental analysis for C 14 H 12 O 4 (Mw: 244): Calculated: C %: 68.85, H %:4.92. Found: C %: 69.05, H %: 4.67.
EXAMPLE 6
120 kg (1.09 kmole) of resorcinol were suspended in 660 l of dichlorethane and 150 kg (1.12 kmole) of anhydrous aluminum chloride were added to the suspension while the temperature raised from 15° C. to 25° C. The complex obtained dissolved in the reaction medium. 171 kg (1.10 kmole) of phenyl-acetyl chloride were added over a period of one hour while the temperature raised to 35°-40° C. The mixture was stirred for one hour thereafter it was admixed with diluted hydrogen chloride (the mixture of 300 l of hydrogen chloride and 600 l of water), and it was treated as described in the preceding Examples. The solvent was removed by distillation, the residue was recrytallized from toluene, the product obtained was centrifuged and dried at 45°-50° C. 205-210 kg of 2,4-dihydroxy-phenyl-benzyl-ketone were obtained, yield 82-84.5%. Calculated amount: 248.5 kg. The physical data are identical with the data given in Example 1.
EXAMPLE 7
27.5 g (0.25 mole) of resorcinol were suspended in 150 ml of dichloroethane and 33.5 g (0.25 mole) of anhydrous aluminum chloride were added. To the solution containing the formed complex 42.9 g (0.2 mole) crude 3,4-dimethyl-phenyl-acetyl-chloride in 50 ml of dichloroethane were added and was stirred for 4 hours. Thereafter the complex was decomposed by adding 1:1 aqueous hydrogen chloride, the dichloro ethane solution containing the desired product was washed with water, the solvent was removed and the residue was recrystallized from toluene. 45.9 g product were obtained, m.p.: 171°-173° C., yield 79.8%. Calculated amount: 57.6 g.
Elemental analysis for C 16 H 16 O 5 (Mw: 288): Calculated: C %: 66.66, H %: 4.17. Found: C %: 66.45, H %: 4.10. The NMR spectrum proved the desired compound.
TLC: Developing system: toluene/n-butyl acetate/acetic acid=8/2/1.
Adsorbent: Kieselgel 60 F 254 (Merck).
Application: 0.2 g/10 ml dimethyl formamide-100 μg.
Front: 16 cm.
Development in UV-light, 254 nm.
R f ˜0.6.
EXAMPLE 8
27.5 g (0.25 mole) resorcinol were suspended in 150 ml of dichloroethane and 33.5 g (0.25 mole) of anhydrous aluminum chloride were added to it. To the solution containing the obtained "complex" 48.5 g (0.2 mole) of 3,4-diethoxy-phenyl-benzyl-acetyl chloride in 50 ml of dichloroethane were added. Thereafter the procedure described in Example 7 was followed. 53.7 g of 2,4-dihydroxy-3',4'-diethoxy-phenyl-benzyl-ketone were obtained after a recrystallization from toluene, m.p.: 141°-143° C. Theoretical amount: 63.2 g. Yield 85%.
Elemental analysis for C 18 H 20 O 5 : Calculated: C %: 68.55, H %: 6.23. Found: C %: 68.35, H %: 6.29.
The NMR data corresponds to the desired product.
TLC: (carried out as described in Example 7): R f ˜0.7. | The invention relates to an improved, large scale process for the preparation of compounds of formula (I) ##STR1## wherein R is halogen atom or hydroxyl,
R 2 is hydrogen atom or hydroxyl,
R 3 and R 4 are hydrogen or alkoxy having 1-6 carbon atoms. | 2 |
FIELD OF THE INVENTION
The present invention relates to highway monitoring systems in general and, more specifically, to systems which detect and signal the existence of a motor vehicle within a predefined detection zone on the roadway.
BACKGROUND OF THE INVENTION
Highway departments use a variety of techniques to monitor traffic in an effort to detect, mitigate, and prevent congestion. Typically, each highway department has a command center that receives and integrates a plurality of signals transmitted by monitoring systems located along the highway. Although different kinds of monitoring systems are used, the most prevalent employs a roadway metal detector. A wire loop is embedded in the roadway and its terminals are connected to detection circuitry that measures the inductance changes in the wire loop. Because the inductance in the wire loop is perturbed by a motor vehicle (comprising a quantity of ferromagnetic material) passing over it, the detection circuitry can detect when a motor vehicle is over the wire loop. Based on this perturbation, the detection circuitry creates a binary signal, called a "loop relay signal," which is transmitted to the highway department's command center. The command center gathers the respective loop relay signals and from them makes a determination as to the likelihood of congestion. The use of wire loops is, however, disadvantageous for several reasons.
First, a wire loop system will not detect a motor vehicle unless the motor vehicle comprises sufficient ferromagnetic material to create a noticeable perturbation in the inductance in the wire loop. And because the trend is to fabricate motor vehicles with non-ferromagnetic alloys, plastics and composite materials, wire loop systems will increasingly fail to detect the presence of motor vehicles. It is already well known that wire loops often overlook small vehicles. Another disadvantage of wire loop systems is that they are expensive to install and maintain. Installation and repair require that a lane be closed, that the roadway be cut and that the cut be sealed. Often too, harsh weather can preclude this operation for several months.
SUMMARY OF THE INVENTION
Embodiments of the present invention monitor highway traffic while avoiding many of the costs and restrictions associated with prior techniques. Specifically, embodiments of the present invention can be installed and maintained in any weather and do not require that the roadway be closed, torn-up or repaved.
These results are obtained in an illustrative embodiment of the present invention which comprises a first electro-acoustic transducer and a second electro-acoustic transducer which receive acoustic energy from a highway and convert the acoustic energy into electrical signals. The electrical signals are then passed through spatial discrimination circuitry, frequency discrimination circuitry and interface circuitry which asserts a binary signal when a motor vehicle is within a detection zone and which retracts the binary signal when no motor vehicle is within the detection zone.
BRIEF DESCRIPTION OF THE DRAWING
FIG. 1 is a drawing of an illustrative embodiment of the present invention as it is used to monitor the presence or absence of a motor vehicle in a detection zone.
FIG. 2 is a drawing of an illustrative microphone array as can be used in the illustrative embodiment of the present invention.
FIG. 3 is a block diagram of the internals of an illustrative detection circuit as shown in FIG. 1.
DETAILED DESCRIPTION
Each motor vehicle using a highway radiates acoustic energy from the power plant (e.g., the engine block, pumps, fans, belts, etc.) and from its motion along the roadway (e.g., tire noise due to friction, wind flow noise, etc.). And while the energy fills the frequency band from DC up to approximately 16 KHz, there is a reliable presence of energy from about 3 KHz to 8 KHz. Embodiments of the present invention exploit this observation for the purpose of highway surveillance.
FIG. 1 depicts a drawing of an illustrative embodiment of the present invention that monitors a pre-defined area of roadway, called a "detection zone," for the presence of a motor vehicle within that area. The salient items in FIG. 1 are roadway 101, motor vehicle 103, motor vehicle 105, detection zone 107, microphone array 111, microphone support 109, detection circuit 115 and interface circuit 119 in a roadside cabinet (not shown), electrical bus 113, electrical bus 117 and lead 121.
As shown in FIG. 2, microphone array 111 preferably comprises a plurality of acoustic transducers (e.g., omni-directional microphones), arranged in a geometric arrangement known as a Mill's Cross. For information regarding Mill's Cross arrays, the interested reader is directed to Microwave Scanning Antenna, R. C. Hansen, Ed., Academic Press (1964), and Principals of Underwater Sound (3rd. Ed.), R. J. Urick (1983). While microphone array 111 could comprise only one microphone, the benefits of multiple microphones (to provide signal gain and directivity, whether in a fully or sparsely populated array or vector, will be clear to those skilled in the art. It will be clear to those skilled in the art how to mechanically baffle microphone array 111 so as to attenuate sounds coming from other than detection zone 107 and to protect microphone array 111 from the environment (e.g., rain, snow, wind, UV).
Microphone array 111 is advantageously rigidly mounted on support 109 so that the predetermined relative spatial positioning of the individual microphones are maintained. A typical deployment geometry is shown in FIG. 1. For this geometry, the horizontal distance of the sensor from the nearest lane with traffic is assumed to be less than 15 feet. The vertical height above the road is advantageously between 20 and 35 feet depending on performance requirements and available mounting facilities. It will be clear to those skilled in the art that the deployment geometry is flexible and can be modified for specific objectives. Furthermore, it will be clear to those skilled in the art how to position and orient microphone array 111 so that it is well suited to receive sounds from detection zone 107.
Referring to FIG. 1, each omni-directional microphone in microphone array 111 receives an acoustic signal which comprises the sound radiated from, inter alia, motor vehicle 103, motor vehicle 105 and ambient noise. Each microphone in microphone array 111 then transforms its respective acoustic signal into an analog electric signal and outputs the analog electric signal on a distinct lead on electrical bus 113 in ordinary fashion. The respective analog electric signals are then fed into detection circuit 115.
To determine the presence or passage of a motor vehicle in detection zone 107, the respective signals from microphone array 111 are processed in ordinary fashion to provide the sensory spatial discrimination needed to isolate sounds emanating from within detection zone 107. The ability to control the spatial directivity of microphone array 111 is called "beam-forming". It will be clear to those skilled in the art that electronically controlled steerable beams can be used to form multiple detection zones.
Referring to FIG. 3, detection circuit 115 advantageously comprises bus 301, vertical summer 305, analog-to-digital converter 313, finite-impulse-response filter 317, bus 303, horizontal summer 307, analog-to-digital converter 315, finite-impulse-response filter 319, multiplier 321 and comparator 325. The electric signals from microphone 201, microphone 203, microphone 205, microphone 207 and microphone 209 (as shown in FIG. 2) are fed, via bus 301, into vertical summer 305 which adds them in well-known fashion and feeds the sum into analog-to-digital converter 313. While in the illustrative embodiment, vertical summer 305 performs an unweighted addition of the respective signals, it will be clear to those skilled in the art that vertical summer 305 can alternately perform a weighted addition of the respective signals so as to shape and steer the formed beam (i.e., to change the position of detection zone 107). It will also be clear to those skilled in the art that illustrative embodiments of the present invention can comprise two or more detection circuits, so that one microphone array can gather the data for two or more detection zones, in each lane or in different lanes.
Analog-to-digital converter 313 receives the output of vertical summer 305, samples it at 32,000 samples per second in well-known fashion. The output of analog-to-digital converter 313 is fed into finite-impulse response filter 317.
Finite-impulse response filter 317 is preferably a bandpass filter with a lower passband edge of 4 KHz, an upper passband edge of 6 KHz and a stopband rejection level of 60 dB below the passband (i.e., stopband levels providing 60 dB of rejection). It will be clear to those skilled in the art how to make and use finite-impulse-response filter 317.
The electric signals from microphone 211, microphone 213, microphone 205, microphone 215 and microphone 217 (as shown in FIG. 2) are fed, via bus 303, into horizontal summer 307 which adds them in well-known fashion and feeds the sum into analog-to-digital converter 315. While in the illustrative embodiment, horizontal summer 307 performs an unweighted addition of the respective signals, it will be clear to those skilled in the art that horizontal summer 307 can alternately perform a weighted addition of the respective signals so as to shape and steer the formed beam (i.e., to change the position of detection zone 107).
Analog-to-digital converter 315 receives the output of horizontal summer 305, samples it at 32,000 samples per second in well-known fashion. The output of analog-to-digital converter 313 is fed into finite-impulse response filter 319.
Finite-impulse response filter 319 is preferably a bandpass filter with a lower passband edge of 4 KHz, an upper passband edge of 6 KHz and a stopband rejection level of 60 dB below the passband (i.e., stopband levels providing p60 dB of rejection). It will be clear to those skilled in the art how to make and use finite-impulse-response filter 319.
Multiplier 321 receives as input the output of finite-impulse-response filter 317 and finite-impulse-response filter 319 and performs a sample by sample multiplication of the respective inputs and then performs a coherent averaging of the respective products. The output of multiplier 321 is fed into comparator 325. It will be clear to those skilled in the art how to make and use multiplier 321.
Comparator 325 advantageously, on a sample-by-sample basis, compares the magnitude of each sample to a predetermined threshold and creates a binary signal which indicates whether a motor vehicle is within detection zone 107. While the predetermined threshold can be a constant, it will be clear to those skilled in the art that the predetermined threshold can be adaptable to various weather conditions and/or other environmental conditions which can change over time. The output of comparator 325 is fed into interface circuitry 119.
Interface circuitry 119 receives the output of detection circuitry 115 and preferably creates an output signal such that the output signal is asserted when a motor vehicle is within detection zone 107 and such that the output signal is retracted when there is no motor vehicle within the detection zone 107. Interface circuitry 119 also makes any electrical conversions necessary to interface to the circuitry at the highway department's command center. Interface circuitry 119 can also perform statistical analysis on the output of detection circuitry 115 so as to output a signal which has other characteristics than that described above. | A method and apparatus for acoustically monitoring a highway is disclosed which is inexpensive to maintain and install and does not require that the roadway be closed, torn-up or repaved. These results are obtained in an illustrative embodiment of the present invention which comprises a Mill's Cross acoustic array mounted proximate to a highway, spatial discrimination circuitry, frequency discrimination circuitry and interface circuitry that generates a binary signal which indicates when a motor vehicle is, or is not, within a detection zone on the roadway. | 6 |
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application contains subject matter that may be related to the subject matter in the following U.S. applications filed on Apr. 22, 2005, and assigned to the assignee of the present application: “Method and Apparatus for Managing and Accounting for Bandwidth Utilization Within A Computing System” with U.S. application Ser. No. 11/112,367 (Attorney Docket No. 03226/643001; SUN050681); “Method and Apparatus for Consolidating Available Computing Resources on Different Computing Devices” with U.S. application Ser. No. 11/112,368 (Attorney Docket No. 03226/644001; SUN050682); “Assigning Higher Priority to Transactions Based on Subscription Level” with U.S. application Ser. No. 11/112,947 (Attorney Docket No. 03226/645001; SUN050589); “Method and Apparatus for Dynamically Isolating Affected Services Under Denial of Service Attack” with U.S. application Ser. No. 11/112,158 (Attorney Docket No. 03226/646001; SUN050587); “Method and Apparatus for Improving User Experience for Legitimate Traffic of a Service Impacted by Denial of Service Attack” with U.S. application Ser. No. 11/112,629 (Attorney Docket No. 03226/647001; SUN050590); “Method and Apparatus for Limiting Denial of Service Attack by Limiting Traffic for Hosts” with U.S. application Ser. No. 11/112,328 (Attorney Docket No. 03226/648001; SUN050591); “Hardware-Based Network Interface Per-Ring Resource Accounting” with U.S. application Ser. No. 11/112,222 (Attorney Docket No. 03226/649001; SUN050593); “Dynamic Hardware Classification Engine Updating for a Network Interface” with U.S. application Ser. No. 11/112,934 (Attorney Docket No. 03226/650001; SUN050592); “Network Interface Card Resource Mapping to Virtual Network Interface Cards” with U.S. application Ser. No. 11/112,063 (Attorney Docket No. 03226/651001; SUN050588); “Network Interface Decryption and Classification Technique” with U.S. application Ser. No. 11/112,436 (Attorney Docket No. 03226/652001; SUN050596); “Method and Apparatus for Enforcing Resource Utilization of a Container” with U.S. application Ser. No. 11/112,910 (Attorney Docket No. 03226/653001; SUN050595); “Method and Apparatus for Enforcing Packet Destination Specific Priority Using Threads” with U.S. application Ser. No. 11/112,584 (Attorney Docket No. 03226/654001; SUN050597); “Method and Apparatus for Processing Network Traffic Associated with Specific Protocols” with U.S. application Ser. No. 11/112,228 (Attorney Docket No. 03226/655001; SUN050598).
[0002] The present application contains subject matter that may be related to the subject matter in the following U.S. applications filed on Oct. 21, 2005, and assigned to the assignee of the present application: “Method and Apparatus for Defending Against Denial of Service Attacks” with U.S. application Ser. No. 11/255,366 (Attorney Docket No. 03226/688001; SUN050966); “Router Based Defense Against Denial of Service Attacks Using Dynamic Feedback from Attacked Host” with U.S. application Ser. No. 11/256,254 (Attorney Docket No. 03226/689001; SUN050969); and “Method and Apparatus for Monitoring Packets at High Data Rates” with U.S. application Ser. No. 11/226,790 (Attorney Docket No. 03226/690001; SUN050972).
[0003] The present application contains subject matter that may be related to the subject matter in the following U.S. applications filed on Jun. 30, 2006, and assigned to the assignee of the present application: “Network Interface Card Virtualization Based On Hardware Resources and Software Rings” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/870001; SUN061020); “Method and System for Controlling Virtual Machine Bandwidth” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/871001; SUN061021); “Virtual Switch” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/873001; SUN061023); “System and Method for Virtual Network Interface Cards Based on Internet Protocol Addresses” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/874001; SUN061024); “Virtual Network Interface Card Loopback Fastpath” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/876001; SUN061027); “Bridging Network Components” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/877001; SUN061028); “Reflecting the Bandwidth Assigned to a Virtual Network Interface Card Through Its Link Speed” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/878001; SUN061029); “Method and Apparatus for Containing a Denial of Service Attack Using Hardware Resources on a Virtual Network Interface Card” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/879001; SUN061033); “Virtual Network Interface Cards with VLAN Functionality” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/882001; SUN061037); “Method and Apparatus for Dynamic Assignment of Network Interface Card Resources” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/883001; SUN061038); “Generalized Serialization Queue Framework for Protocol Processing” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/884001; SUN061039); “Serialization Queue Framework for Transmitting Packets” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/885001; SUN061040).
[0004] The present application contains subject matter that may be related to the subject matter in the following U.S. applications filed on Jul. 20, 2006, and assigned to the assignee of the present application: “Low Impact Network Debugging” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/829001; SUN060545); “Reflecting Bandwidth and Priority in Network Attached Storage I/O” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/830001; SUN060587); “Priority and Bandwidth Specification at Mount Time of NAS Device Volume” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/831001; SUN060588); “Host Operating System Bypass for Packets Destined for a Virtual Machine” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/872001; SUN061022); “Multi-Level Packet Classification” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/875001; SUN061026); “Method and System for Automatically Reflecting Hardware Resource Allocation Modifications” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/881001; SUN061036); “Multiple Virtual Network Stack Instances Using Virtual Network Interface Cards” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/888001; SUN061041); “Method and System for Network Configuration for Containers” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/889001; SUN061044); “Network Memory Pools for Packet Destinations and Virtual Machines” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/890001; SUN061062); “Method and System for Network Configuration for Virtual Machines” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/893001; SUN061171); “Multiple Virtual Network Stack Instances” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/896001; SUN061198); and “Shared and Separate Network Stack Instances” with U.S. Application Serial No. TBD (Attorney Docket No. 03226/898001; SUN061200).
BACKGROUND
[0005] Network traffic is transmitted over a network, such as the Internet, from a sending system (e.g., a computer system) to a receiving system (e.g., a computer system) via a physical network interface card (NIC). The NIC is a piece of hardware found in a typical computer system that includes functionality to send and receive network traffic. Typically, network traffic is transmitted in the form of packets, where each packet includes a header and a payload. The header contains information regarding the source address, destination address, size, transport protocol used to transmit the packet, and various other identification information associated with the packet. The payload contains the actual data to be transmitted from the network to the receiving system.
[0006] Each of the packets sent between the sending system and receiving system is typically associated with a connection. The connection ensures that packets from a given process on the sending system reach the appropriate process on the receiving system. Packets received by the receiving system (via a NIC associated with the receiving system) are analyzed by a classifier to determine the connection associated with the packet.
[0007] Typically, the classifier includes a connection data structure that includes information about active connections on the receiving system. The connection data structure may include the following information about each active connection: (i) the queue associated with the connection; and (ii) information necessary to process the packets on the queue associated with the connection. Depending on the implementation, the connection data structure may include additional information about each active connection. Such queues are typically implemented as first-in first-out (FIFO) queues and are bound to a specific central processing unit (CPU) on the receiving computer system. Thus, all packets for a given connection are placed in the same queue and are processed by the same CPU. In addition, each queue is typically configured to support multiple connections.
[0008] Once the classifier determines the connection associated with the packets, the packets are sent to a temporary data structure (e.g., a receive ring on the NIC) and an interrupt is issued to the CPU associated with the queue. In response to the interrupt, a thread associated with the CPU (to which the serialization queue is bound) retrieves the packets from the temporary data structure and places them in the appropriate queue. Once packets are placed in the queue, those packets are processed in due course. In some implementations, the queues are implemented such that only one thread is allowed to access a given queue at any given time.
SUMMARY
[0009] In general, in one aspect, the invention relates to a method for notifying a packet destination. The method comprises receiving a packet by a network interface card (NIC), wherein the packet destination is a destination of the packet, classifying the packet, forwarding the packet to one of a plurality of receive rings on the NIC, determining whether the one of the plurality of receive rings comprises space to store the packet, dropping the packet if the receive ring does not comprise the space to store the packet, and sending a notification message to the packet destination, wherein the notification message indicates that the packet was dropped by the receive ring.
[0010] In general, in one aspect, the invention relates to a method for notifying a packet destination. The method comprises receiving a packet at a level in a networking path, wherein the level in the networking path comprises one selected from a group consisting of a receive ring, a virtual network interface card (VNIC), an Internet Protocol (IP) layer and a transport layer, determining whether the level can store the packet, dropping the packet if the level cannot store the packet, and sending a notification message to the packet destination, wherein the notification message indicates that the packet was dropped by the level, wherein the networking path is associated with the packet destination.
[0011] In general, in one aspect, the invention relates to a system. The system comprises a network interface card (NIC), comprising a plurality of receive rings, a hardware classifier, wherein the NIC is configured to: receive a packet by a network interface card (NIC), wherein a packet destination is a destination of the packet, classify the packet by the hardware classifier, forward the packet to one of the plurality of receive rings, determine whether the one of the plurality of receive rings comprises space to store the packet, drop the packet if the receive ring does not comprise space to store the packet, and send a notification message to the packet destination, wherein the notification message indicates that the packet was dropped by the receive ring, and a host, operatively connected to the NIC, comprising the packet destination, wherein the host is configured to forward the notification message to the packet destination.
[0012] Other aspects of the invention will be apparent from the following description and the appended claims.
BRIEF DESCRIPTION OF DRAWINGS
[0013] FIG. 1 shows a system in accordance with one embodiment of the invention.
[0014] FIG. 2 shows a virtual network stack in accordance with one embodiment of the invention.
[0015] FIG. 3 shows a notification framework in accordance with one embodiment of the invention.
[0016] FIGS. 4-7 show flow charts in accordance with one embodiment of the invention.
[0017] FIG. 8 shows an example in accordance with one embodiment of the invention.
[0018] FIG. 9 shows a computer system in accordance with one embodiment of the invention.
DETAILED DESCRIPTION
[0019] Specific embodiments of the invention will now be described in detail with reference to the accompanying figures. Like elements in the various figures are denoted by like reference numerals for consistency.
[0020] In the following detailed description of embodiments of the invention, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to one of ordinary skill in the art that the invention may be practiced without these specific details. In other instances, well-known features have not been described in detail to avoid unnecessarily complicating the description.
[0021] In general, embodiments of the invention relate to a method and system for notifying an application that packets destined for the application have been dropped. More specifically, in one or more embodiments of the invention, the application may register to receive notification messages from one or more levels in a networking path (e.g., receive ring, virtual network interface card (VNIC), Internet Protocol (IP) layer, transport layer) associated with the application. Further, the application may register to obtain information about dropped packets associated with a specific connection or socket.
[0022] FIG. 1 shows a system in accordance with one embodiment of the invention. As shown in FIG. 1 , the system includes a host ( 100 ) operatively connected to a network interface card (NIC) ( 102 ). The NIC ( 102 ) provides an interface between the host ( 100 ) and a network (not shown) (e.g., a local area network, a wide area network, a wireless network, etc.). More specifically, the NIC ( 102 ) includes a network interface (NI) (i.e., the hardware on the NIC used to interface with the network) (not shown). For example, the NI may correspond to an RJ-45 connector, a wireless antenna, etc. The packets received by the NI are then sent to other components on the NIC ( 102 ) for processing. In one embodiment of the invention, the NIC ( 102 ) includes a hardware classifier ( 104 ) and one or more hardware receive rings (HRRs) ( 106 A, 106 B, 106 C). In one embodiment of the invention, the HRRs ( 106 A, 106 B, 106 C) correspond to portions of memory within the NIC ( 102 ) used to temporarily store the received packets.
[0023] In one embodiment of the invention, the hardware classifier ( 104 ) is configured to analyze the incoming network traffic, typically in the form of packets, received from the network (not shown). The hardware classifier ( 104 ) may be implemented entirely in hardware (i.e., the hardware classifier ( 104 ) may be a separate microprocessor embedded on the NIC ( 102 )). Alternatively, the hardware classifier ( 104 ) may be implemented in software stored in memory (e.g., firmware, etc.) on the NIC ( 102 ) and executed by a microprocessor on the NIC ( 102 ).
[0024] In one embodiment of the invention, the hardware classifier ( 104 ) is configured to classify packets using one or more of the follow criteria: (i) source Media Access Control (MAC) address, (ii) destination MAC address, (iii) source Internet Protocol (IP) address, (iv) destination IP address, (v) source port number, (vi) destination port number, (vii) protocol-type (e.g., TCP, UDP, etc.). In one embodiment of the invention, the aforementioned classification criteria are obtained from the header of the packet. Said another way, the hardware classifier ( 104 ) uses the header of the packet to classify the packet.
[0025] In one embodiment of the invention, the host ( 100 ) may include the following components: a device driver ( 107 ), a software ring ( 108 ), one or more virtual network interface cards (VNICs) ( 114 A, 114 B, 114 C, 114 D), one or more virtual network stacks (VNSs) ( 116 A, 116 B, 116 C, 116 D), and one or more packet destinations ( 118 ). Each of the aforementioned components is described below.
[0026] In one embodiment of the invention, the device driver ( 107 ) provides an interface between the HRRs ( 106 A, 106 B, 106 C) and the host ( 100 ). More specifically, the device driver ( 107 ) exposes the HRRs ( 106 A, 106 B, 106 C) to the host ( 100 ) such that the host ( 100 ) (or, more specifically, a process executing in the host ( 100 )) may obtain packets from the HRRs ( 106 A, 106 B, 106 C).
[0027] In one embodiment of the invention, the software ring ( 108 ) includes a software classifier ( 110 ) and a number of software receive rings (SRR) (e.g., SRR A ( 112 A), SRR B ( 112 B)). In one embodiment of the invention, the software classifier ( 110 ) has the same functionality as the hardware classifier ( 104 ). However, instead of sending the classified packets to a HRR ( 106 A, 106 B, 106 C), the software classifier ( 110 ) forwards classified packets to one of the SRRs ( 112 A, 112 B). The SRRs ( 112 A, 112 B) are configured to temporarily store the received packets after being classified by the software classifier ( 110 ). In one embodiment of the invention, the software ring ( 108 ) resides in a Media Access Control (MAC) layer (not shown) of the host ( 100 ).
[0028] In one embodiment of the invention, each of the virtual network interface cards (VNICs) ( 114 A, 114 B, 114 C, 114 D) is associated with either a SRR ( 112 A, 112 B) or a HRR ( 106 A, 106 B, 106 C). The VNICs ( 114 A, 114 B, 114 C, 114 D) provide an abstraction layer between the NIC ( 102 ) and the various packet destinations ( 118 ) executing on the host ( 100 ). More specifically, each VNIC ( 114 A, 114 B, 114 C, 114 D) operates like a NIC ( 100 ). For example, in one embodiment of the invention, each VNIC ( 114 A, 114 B, 114 C, 114 D) is associated with one or more Internet Protocol (IP) addresses, one or more Media Access Control (MAC) address, optionally, one or more ports, and, is optionally configured to handle one or more protocol types. Thus, while the host ( 100 ) may be operatively connected to a single NIC ( 102 ), packet destinations ( 118 ) executing on the host ( 100 ) operate as if the host ( 100 ) is bound to multiple NICs. In one embodiment of the invention, the VNICs ( 114 A, 114 B, 114 C, 114 D) reside in a Media Access Control (MAC) layer of the host ( 100 ).
[0029] Each of the VNICs ( 114 A, 114 B, 114 C, 114 D) is operatively connected to a corresponding virtual network stack (VNS) ( 116 A, 116 B, 116 C, 116 D). In one embodiment of the invention, each VNS ( 116 A, 116 B, 116 C, 116 D) includes functionality to process packets in accordance with various protocols used to send and receive packets (e.g., Transmission Communication Protocol (TCP), Internet Protocol (IP), User Datagram Protocol (UDP), etc.). Further, each VNS ( 116 A, 116 B, 116 C, 116 D) may also include functionality, as needed, to perform additional processing on the incoming and outgoing packets. This additional processing may include, but is not limited to, cryptographic processing, firewall routing, etc.
[0030] In one embodiment of the invention, each VNS ( 116 A, 116 B, 116 C, 116 D) includes network layer and transport layer functionality. In one embodiment of the invention, network layer functionality corresponds to functionality to manage packet addressing and delivery on a network (e.g., functionality to support IP, Address Resolution Protocol (ARP), Internet Control Message Protocol, etc.). In one embodiment of the invention, transport layer functionality corresponds to functionality to manage the transfer of packets on the network (e.g., functionality to support TCP, UDP, Stream Control Transmission Protocol (SCTP), etc.). The structure and functionality of the VNSs ( 116 A, 116 B, 116 C, 116 D) is discussed in FIG. 2 .
[0031] As discussed above, the host ( 100 ) includes one or more packet destinations ( 118 ). In one embodiment of the invention, the packet destination(s) ( 118 ) correspond to any process (or group of processes) executing on the host that is configured to send and/or receive network traffic. Further, the packet destination(s) ( 118 ) does not include an internal network stack (i.e., there is no network stack within the packet destination(s)).
[0032] Examples of packet destinations ( 118 ) include, but are not limited to containers, services (e.g., web server), etc. As shown in FIG. 1 , each of the VNSs ( 116 A, 116 B, 116 C, 116 D) is associated with a packet destination ( 118 ). In one embodiment of the invention, each packet destination ( 118 ) is associated with a single VNS ( 116 A, 116 B, 116 C, 116 D). Alternatively, each packet destination is associated with one or more VNSs ( 116 A, 116 B, 116 C, 116 D).
[0033] In one embodiment of the invention, each VNS ( 116 A, 116 B, 116 C, 116 D) is associated with a bandwidth allocation. Those skilled in the art will appreciate that if there is only one VNS ( 116 A, 116 B, 116 C, 116 D) bound to the packet destination ( 118 ), then the bandwidth allocation of the VNS ( 116 A, 116 B, 116 C, 116 D) corresponds to the bandwidth allocated to the packet destination ( 118 ). In one embodiment of the invention, the bandwidth allocation corresponds to the number of packets the packet destination ( 118 ) may receive in a given time interval (e.g., megabytes per seconds). The bandwidth allocation for a given packet destination ( 118 ) is enforced by the VNS ( 116 A, 116 B, 116 C, 116 D) operating in polling mode (discussed in FIG. 6 ).
[0034] In one embodiment of the invention, the VNIC ( 114 A, 114 B, 114 C, 114 D) may be bound to a virtual machine (not shown) (e.g., Xen Domain) instead of a packet destination ( 118 ). In such cases, the VNIC ( 114 A, 114 B, 114 C, 114 D) is bound to an interface (e.g., a Xen interface), where the interface enables the VNIC ( 114 A, 114 B, 114 C, 114 D) to communicate to with the virtual machine In one embodiment of the invention, the aforementioned virtual machine includes its own network stack and its own operating system (OS) instance, which may be different than the OS executing on the host.
[0035] In one embodiment of the invention, each virtual machine is associated with its own MAC address and IP address (which may be static or obtained using Dynamic Host Configuration Protocol (DHCP)). Further, the VNIC associated with the virtual machine includes the same MAC address and IP address as virtual machine with which it is associated.
[0036] FIG. 2 shows a virtual network stack (VNS) in accordance with one embodiment of the invention. In one embodiment of the invention, the VNS ( 200 ) includes an Internet Protocol (IP) layer ( 202 ), an inbound virtual serialization queue (VSQ) ( 204 ), a transport layer ( 206 ), and an outbound serialization queue ( 208 ). Each of the aforementioned components is discussed below.
[0037] In one embodiment, the IP layer ( 202 ) is configured to receive packets from the VNIC associated with the VNS ( 204 ) (e.g., VNS D ( 116 D) receives packets from VNIC D ( 114 D) in FIG. 1 ). Further, the IP layer ( 202 ) is configured to receive packets from the transport layer ( 206 ). In one embodiment of the invention, the IP layer ( 202 ) is configured to perform IP level processing for both inbound and outbound packets.
[0038] Continuing with the discussion of FIG. 2 , the inbound VSQ ( 204 ) is configured to receive packets from the IP layer ( 202 ). The inbound VSQ ( 204 ) corresponds to a queue data structure and is configured to queue packets received from the IP layer ( 202 ) prior to the packets being processed by the transport layer ( 206 ). In one embodiment of the invention, the inbound VSQ ( 204 ) may be used to control the number of packets being received by the packet destination (e.g., 118 ) associated with VNS. The inbound VSQ ( 204 ) may control the bandwidth by limiting the number of packets in the VSQ ( 204 ) and preventing additional packets from entering the VNS ( 200 ) until the inbound VSQ ( 204 ) has less than a threshold number of packets.
[0039] In one embodiment of the invention, the transport layer ( 206 ) is configured to process inbound and outbound packets in accordance with Transmission Control Protocol (TCP), User Datagram Protocol (UDP), or both UDP and TCP. Other protocols may be supported by the transport layer ( 206 ).
[0040] In one embodiment of the invention, the outbound VSQ ( 208 ) is a queue data structure configured to receive packets from the packet destination (e.g., 118 ) with which the VNS ( 204 ) is associated. Further, the outbound VSQ ( 208 ) is configured to store packets prior to sending the received packets to the transport layer ( 206 ). In one embodiment of the invention, the outbound VSQ ( 208 ) is also configured to control the flow of packets from the packet destination (e.g., 118 ) to the VNS ( 200 ). In one embodiment of the invention, the outbound VSQ ( 208 ) (or a related process) is configured to block an application from sending packets to the outbound VSQ ( 208 ) if the packet destination (e.g., 118 ) is attempting to issue packets at a higher rate than the outbound bandwidth allocated to the packet destination (e.g., 118 ). Further, the outbound VSQ ( 208 ) (or a related process) is configured to notify the packet destination (e.g., 118 ) when it is no longer blocked from issuing packets to the VNS ( 200 ).
[0041] In one embodiment of the invention, the inbound VSQ ( 204 ) and outbound VSQ ( 208 ) are each configured to enforce the manner in which packets are processed. Specifically, the inbound VSQ ( 204 ) and outbound VSQ ( 208 ) may be configured to enforce the packet processing requirements imposed by the transport layer ( 206 ). For example, TCP requires serial processing of packets. Thus, the inbound VSQ ( 204 ) and outbound VSQ ( 208 ) may require all threads accessing the inbound VSQ ( 204 ) and outbound VSQ ( 208 ) to conform to a mutual exclusion policy. In one embodiment of the invention, the mutual exclusion policy requires that only one thread may access the VSQ (inbound or outbound) at a time. Thus, if two threads are attempting to access a given VSQ (inbound or outbound), one thread must wait until the other thread has finished accessing the VSQ (inbound or outbound).
[0042] Alternatively, if the transport layer ( 206 ) only supports UDP, then the inbound VSQ ( 204 ) and outbound VSQ ( 208 ) may be configured to allow concurrent access. Said another way, two or more threads may concurrently access the VSQ (inbound or outbound). In one embodiment of the invention, if the transport layer ( 206 ) is configured to process both TCP and UDP packets, then the inbound VSQ ( 204 ) and outbound VSQ ( 208 ) are configured to conform to the more stringent standard (e.g., TCP if the transport layer supports both TCP and UDP).
[0043] In one embodiment of the invention, the inbound VSQ ( 204 ) and the outbound VSQ ( 208 ) are implemented as a single bi-directional VSQ. In such cases, the bi-directional VSQ includes a single set of configuration parameters (discussed above) to enforce the manner in which packets are processed. Further, the enforcement of the configuration parameters is performed on a VSQ-basis (as opposed to a per-direction basis). For example, if the bi-directional VSQ enforces a mutual exclusion policy, then only one thread may access the bi-directional VSQ at a time.
[0044] FIG. 3 shows a notification framework in accordance with one embodiment of the invention. As shown in FIG. 3 , a packet (P) destined for the packet destination ( 308 ) passes through a number of levels (collectively referred to as a networking path). The packet destination for a packet is known at the time the packet enters the networking path as the packet may only enter the networking path if the packet is classified as being associated with the packet destination (e.g., when the destination IP address of the packet corresponds to an IP address associated with the packet destination).
[0045] As shown in FIG. 3 , the networking path associated with the packet destination ( 308 ) includes a receive ring ( 300 ), a virtual network interface card (VNIC) ( 302 ), an IP layer ( 304 ), and a transport layer ( 306 ). As shown in FIG. 3 , the IP layer ( 304 ), and the transport layer ( 306 ) are included in the virtual network stack ( 310 ).
[0046] Though not shown in FIG. 3 , each of the aforementioned levels is associated with at least one bidirectional queue (or, alternatively, two unidirectional queues). The bidirectional queues (or unidirectional queues) are typically first-in-first-out (FIFO) queues configured to temporarily store a finite number of packets prior to the packets being processed by corresponding level. For example, the bidirectional queue in the IP layer ( 304 ) is configured to store a finite number of inbound packets (i.e., packets received from the VNIC ( 302 )) and outbound packets (i.e., packets received from the Transport Layer ( 306 )) prior to the IP layer ( 304 ) processing the packets. In one embodiment of the invention, there is a bidirectional (or two unidirectional queues) for each TCP connection and/or UDP socket currently being used by an application (or applications) in the packet destination ( 308 ).
[0047] Further, for each direction in the bidirectional queue (or each of the unidirectional queues) there is a drop counter. The drop counter is initially set to zero and is incremented each time a packet is received by the level but is not stored in appropriate queue (i.e., the queue is full). In addition, for each direction in the bidirectional queue (or each of the unidirectional queues) there may also be an error packet counter. The error packet counter is initially set to zero and is incremented each time a packet associated with an error is received by the level. A packet is said to be associated with an error, if there is an error in the header of the packet. The error may include but is not limited to an incorrect or partial MAC address, an incorrect or partial IP address, etc.
[0048] As shown in FIG. 3 , each level in a networking path associated with the packet destination ( 308 ) is configured to send a notification message (NM) to the packet destination ( 308 ). The NM may be sent in response to a dropped packet and/or an error packet. As shown in FIG. 3 , the NM may be sent as an out-of-band channel (i.e., a different communication path than the incoming packets). In one embodiment of the invention, the out-of-band channel may correspond, but is not limited, to an event port framework, a door call, or a call back function provided during registration of the packet destination with the host. Alternatively, the NM is sent using an in-band channel (i.e., on the same communication path as other incoming packets). For example, the NM would be sent up the networking path through all levels between the level in which the NM was generated and the packet destination ( 308 ).
[0049] In one embodiment of the invention, the NM may only include a notification that one packet (or a certain number of packets) for the packet destination has been dropped by a specific level. Alternatively, the NM may include additional information about the packet that was dropped. For example, the NM may include information about the connection or socket with which the packet was associated.
[0050] While FIG. 3 shows a single packet destination with a single networking path. As shown in FIG. 1 , the system may include multiple networking paths and each networking path may include functionality as discussed in FIG. 3 . Accordingly, each of the packet destinations in the system may register with the host ( 312 ) and receive notification message about dropped packets and/or error packets, where the dropped packets and/or error packets are associated with the packet destination ( 308 ).
[0051] FIG. 4 shows a flow chart in accordance with one or more embodiments of the invention. More specifically, FIG. 4 shows a method for setting up a system in accordance with one embodiment of the invention. Initially, the NIC is registered and the appropriate device driver is used to obtain hardware information about the network interface card (NIC) (e.g., number of HRRs, APIs to program the hardware classifier, control functions to support interrupt and polling mode, etc.) (Step 401 ). Once Step 401 is completed, a determination is made regarding the number of VNICs that need to be created on the host (Step 403 ). In one or more embodiments of the invention, the number of VNICs required corresponds to the number of packet destinations on the host.
[0052] Once the number of VNICs to be created has been determined, the number of hardware receive rings on the NIC is assessed (Step 405 ). VNICs are subsequently created in the host, where the number of VNICs created corresponds to the number of VNICs determined in Step 403 (Step 407 ). Next, a determination is made about whether there are fewer HRRs than VNICs on the host (Step 409 ). If there are fewer HRRs than VNICs on the host, then a software ring is created in the host and subsequently associated with one of the HRRs (Step 411 ).
[0053] A set of software receive rings (SRRs) is then created within the software ring (Step 413 ). The VNICs are then bound to the SRRs (Step 415 ). More specifically, the VNICs that cannot be bound to the HRRs are bound to the SRRs. Then, the remaining VNICs are bound to the HRRs (Step 417 ). The hardware classifier (in the NIC) and the software classifier (if host includes a software ring) are programmed (Step 419 ). In one embodiment of the invention, programming the hardware classifier and software classifier includes specifying to which HRR or SRR to send the received packets. The hardware classifier may be programmed using an API advertised by the device driver (see Step 401 . Those skilled in the art will appreciate that steps in FIG. 4 may be a different order.
[0054] In one embodiment of the invention, programming the hardware classifier includes specifying that all packets for a specific packet destination are sent to a specific HRR. In one embodiment of the invention, the hardware classifier is programmed using the MAC address and, optionally, the IP address associated with the packet destinations. Thus, all packets with a specific MAC address (and optionally an IP address) are sent to a specific HRR. As discussed, the HRRs are bound to VNICs or software rings. Thus, packets sent to specific HRRs are subsequently sent to the appropriate VNIC or software ring.
[0055] In the case where the packets are sent to the software ring, the software classifier in the software ring performs additional classification. In one embodiment of the invention, the software classifier includes the same functionality as the hardware classifier and is programmed using the same criteria (e.g., MAC addresses, IP addresses, etc.) as the hardware classifier.
[0056] In one embodiment of the invention, VNICs are preferably bound to an HRR if an HRR is available and the hardware classifier in the NIC is configured to perform the level of classification required by the host. In such cases, one HRR is bound to a software ring and the other HRRs are bound to VNICs. In one embodiment of the invention, each of the aforementioned VNICs is associated with a virtual network stack (VNS), which is in turn associated with a packet destination (see FIG. 1 ).
[0057] As stated above, software rings can be arbitrarily created on top of HRR or SRRs. As a result, different structures involving software rings can be created to handle the same number of VNICs using the method shown in FIG. 4 .
[0058] FIG. 5 shows a flowchart in accordance with one embodiment of the invention. More specifically, FIG. 5 shows a flowchart for registering an application to receive a notification message. Initially, the packet destination to receive the notification messages and the level from which to receive the notification message are selected (Step 500 ). Said another way, the packet destination that is the target of the notification message and the specific level in the networking path (e.g., receive ring, VNIC, IP layer, and TCP layer) from which the notification message is generated is selected. Once the packet destination and level has been selected, a TCP connection or a UDP socket may be optionally selected (Step 502 ).
[0059] Step 502 is typically performed when a given networking path includes packets for multiple TCP connections and/or UDP sockets and the packet destination (or application executing therein) only wants to receive notification messages related to the specific TCP connection or UDP socket. Thus, instead of receiving notification messages when any packet drops, the packet destination (or application therein) only receives notification messages that packets associated with the selected TCP connection or UDP socket have been dropped. If the networking path only receives packets associated with a single TCP connection or UDP socket, or if the packet destination (or application therein) does not require per-TCP connection or per-UDP socket granularity, then Step 502 may not be performed.
[0060] The notification type and the notification threshold are subsequently set (Step 504 ). In one embodiment of the invention, the notification type corresponds to dropped packet notification or error packet notification. Drop packet notification corresponds to notifying the packet destination that a packet has dropped. Similarly, error packet notification corresponds to notifying the packet destination that there is an error packet.
[0061] In one embodiment of the invention, the notification threshold corresponds to a minimum number of packets that must be dropped (as recorded by the drop counter) or a minimum number of error packets that must be received (as recorded by the error packet counter) before a notification message is sent to the packet destination. For example, the notification threshold may be set to ten, accordingly, a notification message is sent every time ten packets have been dropped. Typically, once the notification message is sent the corresponding counter (drop or error packet) is reset to zero.
[0062] The notification is subsequently registered with the host using the information specified in Steps 500 - 504 (Step 506 ). At this stage, the notification has been set and the packet destination (i.e., the packet destination specified in Step 500 ) may receive notification messages from the level specified in Step 500 . A determination is then made about whether additional notifications need to be registered in the host (Step 508 ). If additional notifications need to be registered, then the process proceeds to Step 500 . Alternatively, the process ends. The process in FIG. 5 may be repeated for each packet destination on the host as well as for both dropped packets and error packets.
[0063] FIG. 6 shows a flow chart in accordance with one or more embodiments of the invention. More specifically, FIG. 6 shows a method for processing received packets in accordance with one embodiment of the invention. Initially, packets are received by a NIC (Step 600 ). Next, a hardware classifier associated with the NIC determines to which receive ring (e.g., HRR) to send the packets (Step 602 ). The packets are then sent to the appropriate receive ring (Step 604 ) based on the classifier's assessment.
[0064] Continuing with the discussion in FIG. 6 , a determination is then made about whether the receive ring is associated with a software receive ring (Step 606 ). If the receive ring is associated with a software receive ring, then the packets are forwarded to a software classifier (Step 608 ). If Step 602 is entered from Step 608 , then classifier in Step 602 now corresponds to a software classifier and all references to receive rings in Steps 602 - 622 correspond to SRRs. Said another way, when Steps 602 - 606 are initially performed, the classifier corresponds a hardware classifier and the receive rings correspond to HRRs. However, if the HRR is bound to a software ring (see Step 606 ), then in all subsequent executions of Steps 602 - 622 , the classifier corresponds to a software classifier and all references to receive rings in Steps 602 - 622 correspond to SRRs.
[0065] If the receive ring is not associated with a software ring, then a determination is made about whether the receive ring (HRR or SRR) is associated with a virtual machine or a packet destination (Step 610 ). The receive ring is associated with the virtual machine if the receive ring sends (via a VNIC) received packets to an interface, which in turn sends packets to a virtual machine Similarly, the receive ring is associated with a packet destination if the receive ring (via a VNIC) sends packets to a VNS, which in turn sends packets to a packet destination.
[0066] If the receive ring is associated with a packet destination, the process proceeds to Step 612 . Alternatively, if the receive ring is associated with a virtual machine, then the process proceeds to Step 616 . With respect to Step 612 , a determination is made about whether the VSQ associated with the VNS is operating in polling mode or interrupt mode.
[0067] Continuing with the discussion of FIG. 6 , if the VSQ is operating in polling mode, then the packets remain in the receive ring (HRR or SRR) until the VSQ requests a specified number of packets from the receive ring (Step 614 ). In one embodiment of the invention, the VSQ does not request any packets when there are packets already queued on the VSQ. In one or more embodiments of the invention, the VSQ retrieves all packets from the receive ring when a request is made for packets.
[0068] Those skilled in the art will appreciate that the receive rings store a finite number of packets. Thus, if the receive rings receive packets at a faster rate than the rate at which the corresponding VSQ requests the packets, the receive rings will eventually fill completely with packets and packets received after this point are dropped until packets on the receive rings are requested and processed. As discussed above, if the packet destination has registered with the host to receive notification regarding dropped packets, then notification messages are sent to the packet destination (see FIG. 7 ). In one embodiment of the invention, the rate at which packets are requested from the receive ring (SRR or HRR) and the number of packets requested is determined by the bandwidth allocation of the VNS bound to the receive ring.
[0069] Alternatively, if the VSQ is operating in interrupt mode, then an interrupt is issued to a processor (i.e., a processor bound to the VSQ that is bound to the VNS associated with the receive ring or the processor bound to the interface associated with the VM) (Step 616 ). In one embodiment of the invention, if the receive ring is an SRR and it is bound to a VNIC, then the interrupt (as recited in Step 616 ) is a software interrupt as opposed to a hardware interrupt (as recited in Step 616 ), which is generated when the HRR is bound to a VNIC. The packets are then sent to the VNIC (Step 618 ).
[0070] In one embodiment of the invention, if the VSQ is operating polling mode, then the VSQ, which includes a copy of the appropriate acceptor function, uses the acceptor function to obtain the packet from the receive ring and place it in the appropriate VNIC. Alternatively, if the VSQ is operating in interrupt mode, then the device driver (or NIC) executes the acceptor function to send the packet from the receive ring to the appropriate VNIC.
[0071] The VNIC subsequently sends the packets to the appropriate VNS or interface (Step 620 ), where the packets are processed and then sent to the packet destination or virtual machine (Step 622 ).
[0072] FIG. 7 shows a flow chart in accordance with one or more embodiments of the invention. More specifically, FIG. 7 shows a method for notifying a packet destination that is registered to receive notification that a packet has been dropped. Note the packet that is dropped is associated with the packet destination (e.g., when the destination IP address of the packet corresponds to an IP address associated with the packet destination). Further, the method shown in FIG. 7 occurs each time a packet is received by a level in the networking path associated with the packet destination. In addition, the method shown in FIG. 7 may be performed concurrently at each level in the networking path associated with the packet destination. Moreover, the method shown in FIG. 7 may be performed concurrently in multiple networking paths within the host.
[0073] Turning to the FIG. 7 , initially, a packet is received at a level (e.g., receive ring, VNIC, IP layer, transport layer) (Step 700 ). A determination is then made about whether there is space in the appropriate queue (bidirectional or unidirectional) to store the packet (Step 702 ). If there is space in the appropriate queue, then the packet is stored in the appropriate queue (Step 704 ) and the method ends.
[0074] Alternatively, if there is no space in the appropriate queue, then the packet is dropped (Step 706 ) (i.e., not stored in the queue and, thus, not processed any further by the host). The drop counter is subsequently incremented (Step 708 ). A determination is then made about whether the notification threshold is been exceeded (Step 710 ). The aforementioned determination is made using the drop counter incremented in Step 708 . If the notification threshold is exceeded, then a notification message is sent to the packet destination (i.e., the packet destination with which the packet is associated) (Step 712 ). Alternatively, if the notification threshold is not exceeded, then the process ends and no notification message is sent.
[0075] In one embodiment of the invention, if the packet destination is associated with multiple TCP connections or UDP sockets and the packet destination has only registered to receive packets associated with a specific connection then one of the two following embodiments may be implemented: (i) the hardware classifier is configured to only forward packets associated with the specific TCP connection or UDP socket to a receive ring, where the receive ring is in the networking path associated with the packet destination. In this case, no additional processing is required when sending the notification message. or (ii) the hardware classifier forwards all packets for the packet destination to a single receive ring. In this scenario, if there are multiple TCP connections or UDP sockets associated with the packet destination, then a separate drop counter is maintained for each TCP connection or UDP socket and step 710 is modified to determine whether the drop counter associated with the specific TCP connection or UDP socket has exceeded the threshold.
[0076] A method similar to the method shown in FIG. 7 may be used to send notification messages corresponding to error notification messages to the packet destination. In such cases, step 702 is modified to determine whether the packet is an error packet and step 708 is modified to increment the error packet counter.
[0077] Embodiments of the invention enable a packet destination (or an application executing therein) to register and receive notifications of dropped packets at all levels within the associated networking path (i.e., the networking path associated with the packet destination). Further, embodiments of the invention allow the packet destination (or an application executing therein) to specify the specific UDP socket or TCP connection about which to receive notifications (i.e., when packets associated with the specific UDP socket or TCP connection are dropped).
[0078] In addition to providing the packet destination (or an application executing therein) immediate notification of dropped packets, embodiments of the invention also enable the packet destination (or an application executing therein) to take action in response to receiving notification of dropped packets (or error packets).
[0079] For example, if a packet destination (or an application executing therein) receives notification of dropped packets, the packet destination (or an application executing therein) may re-route packets in the network on which the host is located or, alternatively, change the encoding of data or video streams to reduce the number of packets being sent to the packet destination (or an application executing therein).
[0080] Finally, embodiments of the invention enable the system administrators to identify when and where packets are being dropped. Using the aforementioned information, the system administrators may be able to more effectively and efficiently allocate host networking resources (e.g., queue sizes, processor cycle allocation to processes inbound and outbound packets, etc.).
[0081] FIG. 8 shows an example in accordance with one embodiment of the invention. The example is not intended to limit the scope of the invention. Turning to FIG. 8 , the system includes a NIC ( 826 ) operatively connected to a host ( 828 ). The NIC ( 826 ) includes two receive rings ( 800 , 810 ) and a hardware classifier ( 824 ). The hardware classifier ( 824 ) is configured to forward packets (P 1 ) for packet destination 1 ( 808 ) to receive ring 1 ( 800 ) and to forward packets for packet destination 2 ( 818 ) to receive ring 2 ( 818 ).
[0082] As shown in FIG. 1 , packets (P 1 ) for packet destination 1 ( 808 ), once sent to receive ring 1 ( 800 ), pass through VNIC 1 ( 802 ), IP layer 1 ( 804 ) and transport layer 1 ( 806 ) and eventually reach packet destination 1 ( 808 ). As shown in FIG. 8 , IP layer 1 ( 804 ) and transport layer 1 ( 806 ) are included in VNS 1 ( 820 ). Similarly, packets (P 2 ) for packet destination 2 ( 818 ), once sent to receive ring 2 ( 810 ), pass through VNIC 2 ( 812 ), IP layer 2 ( 814 ) and transport layer 2 ( 816 ) and eventually reach packet destination 2 ( 818 ). As shown in FIG. 8 , IP layer 2 ( 814 ) and transport layer 2 ( 816 ) are included in VNS 2 ( 822 ).
[0083] Receive ring 1 ( 800 ), VNIC 1 ( 802 ), IP layer 1 ( 804 ) and transport layer 1 ( 806 ) are collectively referred to as the networking path associated with packet destination 1 ( 808 ). Receive ring 2 ( 810 ), VNIC 2 ( 812 ), IP layer 2 ( 814 ) and transport layer 2 ( 816 ) are collectively referred to as the networking path associated with packet destination 2 ( 818 ).
[0084] As shown in FIG. 8 , packet destination 1 ( 808 ) has registered to receive a notification message (NM 1 ) when receive ring 1 ( 800 ) drops a packet. NM 1 (as shown in FIG. 8 ) is communicated to packet destination 1 using an out-of-band communication channel. Packet destination 1 ( 808 ) has also registered to receive a notification message (NM 3 ) if a certain number of error packets are received by transport layer 1 ( 806 ). NM 3 is communicated using an in-band communication channel. Finally, packet destination 2 ( 818 ) has registered to receive a notification message (NM 2 ) if packets are dropped by IP layer 2 ( 814 ). NM 2 , like NM 1 , is communicated to packet destination 2 ( 818 ) using an out-of-band communication channel.
[0085] In one embodiment of the invention, each of the levels in the networking path is additionally configured to perform the following: (i) receive a packet; (ii) determine whether the level above the current level (e.g., a receive ring ( 300 in FIG. 3 ) may query the VNIC ( 302 in FIG. 3 ) to determine whether the VNIC includes space to store the packet; (iii) if the packet can be stored in the next level (i.e., the next level has space to store the packet), then the packet is sent to the next level; and (iv) if the next level cannot store the packet (i.e., the next level has no space to store the packet), then the packet is dropped and either the current level or the next level update the appropriate drop counters and then determine whether to issue a notification message to the packet destination in accordance with embodiments of the invention discussed above.
[0086] An embodiment of the invention may be implemented on virtually any type of computer regardless of the platform being used. For example, as shown in FIG. 9 , a networked computer system ( 900 ) includes a processor ( 902 ), associated memory ( 904 ), a storage device ( 906 ), and numerous other elements and functionalities typical of today's computers (not shown). The networked computer ( 900 ) may also include input means, such as a keyboard ( 908 ) and a mouse ( 910 ), and output means, such as a monitor ( 912 ). The networked computer system ( 900 ) is connected to a local area network (LAN) or a wide area network via a network interface connection (not shown). Those skilled in the art will appreciate that these input and output means may take other forms. Further, those skilled in the art will appreciate that one or more elements of the aforementioned computer ( 900 ) may be remotely located and connected to the other elements over a network. Further, software instructions to perform embodiments of the invention may be stored on a computer readable medium such as a compact disc (CD), a diskette, a tape, a file, or any other computer readable storage device.
[0087] While the invention has been described with respect to a limited number of embodiments, those skilled in the art, having benefit of this disclosure, will appreciate that other embodiments can be devised which do not depart from the scope of the invention as disclosed herein. Accordingly, the scope of the invention should be limited only by the attached claims. | A method for notifying a packet destination that includes receiving a packet by a network interface card (NIC), where the packet destination is a destination of the packet, classifying the packet, forwarding the packet to one of a plurality of receive rings on the NIC, determining whether the one of the plurality of receive rings comprises space to store the packet, dropping the packet if the receive ring does not comprise the space to store the packet, and sending a notification message to the packet destination, where the notification message indicates that the packet was dropped by the receive ring. | 7 |
This application is a continuation of application Ser. No. 282,239 filed on July 10, 1981, now abandoned.
BACKGROUND AND SUMMARY OF THE INVENTION
The present invention relates to an analog display of the segmented type for displaying a level of a detected signal.
LED (light emitting diode) level meters have been used in audio reproduction systems for displaying the level of input signals. A typical drive system for controlling the number of lighted LEDs in response to the level of the input signal is disclosed in, for example, U.S. Pat. No. 3,796,951, "SOLID STATE ELECTRONIC GAUGE" issued on Mar. 12, 1974, and U.S. Pat. No. 4,017,796, "ELECTRICAL CIRCUIT MEANS FOR USE IN ANALOGUE DISPLAY AND/OR CONTROL SYSTEM" issued on Apr. 12, 1977.
When the above-mentioned LED level meter is used to display the level of the stereo sound signal, two sets of the LED level meters are employed in the conventional system for displaying the right channel signal level and the left channel signal level, respectively.
Accordingly, an object of the present invention is to provide an analog display of the segmented type which displays the levels of plural signals at a same time.
Another object of the present invention is to provide an LED level meter for displaying a stereo sound signal level through the use of one array of LEDs.
Other objects and further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. It should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
To achieve the above objects, pursuant to an embodiment of the present invention, a row of light emitting diodes are provided for indicating the level of one input signal from the left end of the row and for indicating the level of another input signal from the right end of the row. The one input signal can be the left channel sound signal, and the other input signal can be the right channel sound signal when the present level meter is used for displaying the audio signal level of the stereo sound.
In a preferred form, ten (10) light emitting diodes are aligned in a row to which a driver circuit is connected. The driver circuit functions to enable a preselected number of light emitting diodes from the left end of the row in response to the level of the left channel sound signal. The driver circuit further functions to enable a preselected number of light emitting diodes from the right end of the row in response to the level of the right channel sound signal. The driver circuit further functions to drive the light emitting diode which is located at the position where the number of diodes to be illuminated from the left end and the right end overlap each other at a brightness higher than the remaining light emitting diodes.
In another preferred form, a row of the light emitting diodes is connected to a driver circuit which functions to enable one light emitting diode representing the level of the input signal. More specifically, when the left channel sound signal has the level corresponding to four (4) LEDs and the right channel sound signal has the level corresponding to three (3) LEDs, the fourth LED counted from the left end of the row and the third LED counted from the right end of the row are enabled.
BRIEF DESCRIPTION OF THE DRAWINGS
The present invention will be better understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention and wherein:
FIG. 1 is a circuit diagram of an embodiment of a driver circuit of the present invention;
FIG. 2 is a circuit diagram of another embodiment of a driver circuit of the present invention; and
FIG. 3 is a block diagram of a level discriminator included in the driver circuit of FIG. 2.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 shows an embodiment of a level meter of the present invention, wherein the stereo sound signal level is displayed through the use of an array of ten (10) light emitting diodes LED 1 through LED 10 .
The left channel signal level is displayed from the left end of the LED array, and the right channel signal level is displayed from the right end of the LED array. When the left channel signal has the level corresponding to four (4) LED segments, the LEDs LED 1 through LED 4 are enabled. At the same time, when the right channel signal has the level corresponding to two (2) LED segments, the LEDs LED 9 and LED 10 are enabled. That is, the LEDs LED 1 , LED 2 , LED 3 , LED 4 , LED 9 and LED 10 are enabled.
Each anode electrode of the LEDs is connected to a DC power source +Vcc. Each cathode electrode of the LEDs is connected to a parallel circuit including a series circuit of a resistor R Li and a transistor T Li , and a series circuit of a resistor R Rj and a transistor T Rj . The transistor T Li is connected to receive a switching signal from an input terminal Li for displaying the level of the left channel sound signal, and the transistor T Rj is connected to an input terminal Rj to receive a switching signal for displaying the level of the right channel sound signal. A right channel sound signal level discriminator is provided for developing the switching signal to be applied to the input terminal Rj, and a left channel sound signal level discriminator is provided for developing the switching signal to be applied to the input terminal Li.
In the foregoing example, when the left channel signal has the level corresponding to four (4) LED segments, the input terminals L 1 through L 4 receive the switching signal of the high level. Further, when the right channel signal has the level corresponding to two (2) LED segments, the input terminals R 1 and R 2 receive the switching signal of the high level. Thus, the transistors T L1 , T L2 , T L3 , T L4 , T R1 and T R2 are switched on to enable the LEDs LED 1 , LED 2 , LED 3 , LED 4 , LED 9 and LED 10 .
If the left channel sound signal has the level corresponding to five (5) LED segments and the right channel sound signal has the level corresponding to seven (7) LED segments, the transistors T L1 through T L5 and T R1 through T R7 are switched on. Therefore, the LEDs LED 4 and LED 5 emit light higher than the remaining LEDs. More specifically, when the left channel signal level measured from the left end of the LED array and the right channel signal level measured from the right end of the LED array overlaps each other, the overlapped portion is driven to emit light stronger than the remaining LEDs.
FIG. 2 shows another embodiment of a level meter of the present invention, wherein the stereo sound signal level is displayed through the use of an array of five (5) light emitting diodes LED I through LED V . In this embodiment, when the left channel sound signal has the level corresponding to one (1) LED segment and the right channel sound signal has the level corresponding to two (2) LED segments, the light emitting diodes LED I and LED IV are enabled.
Each anode electrode of the LEDs is connected to a DC power source +Vcc. Each cathode electrode of the LEDs is connected to a switching transistor TL i1 which receives a switching signal derived from a left channel sound signal level discriminator DL. Each of the cathode electrodes is further connected to a switching transistor TR j1 which is connected to receive a switching signal derived from a right channel sound signal level discriminator DR.
FIG. 3 schematically shows the construction of the right channel sound signal level discriminator DR. The level discriminator DR includes comparators C 1 through C 5 . A reference voltage signal VR 1 is applied to the reference input terminal of the comparator C 1 and the data input terminal of the comparator C 1 receives the right channel sound signal R in . The right channel sound signal R in is applied to the each of the data input terminals of the comparators. The reference voltage signal VR 2 is higher than the reference voltage signal VR 1 . The reference voltage signal VR 5 is higher than the reference voltage signal VR 4 which is higher than the reference voltage signal VR 3 which, in turn, is higher than the reference voltage signal VR 2 . When the right channel sound signal has the level corresponding to two (2) LED segments, the comparators C 1 and C 2 develop a switching signal of the high level at output terminals R 1 and R 2 , respectively. The left channel sound signal level discriminator DL has the same construction as the right channel sound signal level discriminator DR.
In the embodiment of FIG. 2, when the left channel sound signal has the level corresponding to two (2) LED segments, the left channel sound signal level discriminator DL develops the switching signal of the high level at its output terminals L 1 and L 2 . The switching signal derived from the output terminal L 1 functions to switch on the transistor TL 11 . The switching signal derived from the output terminal L 2 functions to switch on the transistor TL 21 . The switching signal derived from the output terminal L 2 further functions to turn on a transistor TL 12 . When the transistor TL 12 is made conductive, the base electrode of the transistor TL 11 is forced to the ground level and, therefore, the transistor TL 11 is made non-conductive. Accordingly, the light emitting diode LED I is disabled, and only the light emitting diode LED II is enabled. The similar operation is conducted in the right channel side. Thus, when the left channel sound signal has the level corresponding to two (2) LED segments and the right channel sound signal has the level corresponding to one (1) LED segment, the light emitting diodes LED II and LED V are simultaneously enabled.
The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications are intended to be included within the scope of the following claims. | A stereo sound level display device includes a single array of light emitting diodes aligned in a line. The left channel sound signal level is detected to display the left channel sound signal level from the left end of the light emitting diode array. At the same time, the right channel sound signal level is detected to display the right channel sound signal level from the right end of the light emitting diode array. | 6 |
FIELD OF THE INVENTION
The present invention is directed to a sock having a knitted-in carry-all compartment and, more particularly, to a sock having a locking cuff which, when folded over a storage compartment, serves to lock items in the storage compartment. A method of making such a sock is also disclosed.
BACKGROUND OF THE INVENTION
Athletes, particularly joggers, tennis players and the like, often encounter the problem that their sportsclothes do not have any pockets in which to carry necessary items, such as house and/or car keys. Moreover, the problem is not limited to athletic clothes. Oftentimes, jogging suits and other loungewear worn around the house are also pocketless, leaving the wearer with no convenient way to carry various small items.
One prior solution to this problem has been to provide storage areas which are sewn or glued to the side of one or both socks. This solution is not ideal, however, as it results in a clumsy, bulky pocket attached to the sock, which makes the sock uncomfortable to wear. Further, the pocket may accidently get caught on something and be ripped off, thus dumping out its contents. Moreover, the method of making these socks requires a separate gluing or sewing operation once the knitting operation is completed, which adds to the time and cost required to make the socks.
SUMMARY OF THE INVENTION
The present invention overcomes the above problem by providing a sock having a storage compartment knitted directly into the sock. In a preferred embodiment, the sock includes a foot portion and a two-layer upper portion. The inner layer extends upwardly of the outer layer, thus forming a locking cuff. Items, such as keys, may be inserted between the inner layer and the outer layer, and then the locking cuff is folded over the outer layer to securely lock the items within the storage compartment.
The sock in accordance with the present invention can be made on any circular hosiery knitting machine with dial attachment. In a preferred embodiment of the method according to the present invention, the knitting machine knits the inner locking cuff layer in the usual manner until it reaches a predetermined point for beginning the storage area. Then the cams on the main drum of the knitting machine and the kick links in the chain are arranged to begin inserting the storage area into the desired course. Initially, every other needle is raised up prior to reaching the yarn feed area. Then, as the needles approach the knitting cam, the needle divider cam is dropped in to force the needles not lifted up under the stitch cam block. This results in only every other needle being in an "active" knitting position. Concurrently, the dial bits are activated so that there will be two dial bits between each "active" needle. As the needles take on yarn, so do all of the dial bits. Once all of the dial bits have taken on yarn, they are drawn partially in to hold the stitches at the desired course. The knitting machine is then reset to resume normal knitting operations.
Normal knitting operations continue until the desired storage area length is reached. To release the held stitches and tie them into the sock after knitting the storage area, the previously "inactive" needles are interposed between the dial bits holding the yarn. As the bits are retracted, the yarn is forced off the bits by these previously inactive needles. The knitting machine is then set to resume normal knitting operations to finish out the length of the sock and to form the foot portion. Importantly, to ensure that a locking cuff is created, the length of the storage area cannot be longer than that of the inner locking cuff layer of the sock.
BRIEF DESCRIPTION OF THE DRAWINGS
These and other aspects of the invention are apparent from the attached drawings, in which:
FIG. 1 is a front perspective view of a sock in accordance with a preferred embodiment of the present invention;
FIG. 2 is a front perspective view as in FIG. 1, but with the locking cuff folded downwardly; and
FIG. 3 is a front perspective view as in FIG. 1, but with the entire outer layer folded downwardly to show the intersection line where the storage area is tied into the sock.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
A sock in accordance with a preferred embodiment of the present invention is illustrated in FIGS. 1-3, and is generally designated 10. Throughout the Figures, like numerals will be used to designate like elements.
Sock 10 includes a foot portion 12 and a two-layer storage area formed by outer storage compartment layer 14 and inner locking cuff layer 16. As shown in FIG. 3, the storage area is knitted into the foot portion at course A. It is to be understood that course A, the point at which the storage area begins, may be selected so as to be disposed anywhere on the wearer's leg from the ankle upwards, depending on the length of sock and the length of storage compartment desired.
The wearer may insert items to be stored in between the inner and outer layers shown in FIG. 1. Then the inner locking cuff layer 16 is folded downwardly to cover the top edge of the outer layer 14, as shown in FIG. 2, so that items stored within the storage compartment are locked securely therein.
A preferred method of manufacturing the sock shown in FIGS. 1-3 and the improved machine used therein is described in the following. The basic machine and its operation are conventional and known, such as the models 302 and AMY II manufactured by Speizman Industries, Inc., Charlotte, North Carolina.
In a preferred embodiment of the method according to the present invention, a circular hosiery knitting machine having 108 needles begins knitting the sock from the upper edge of the sock downwardly, i.e., knits the locking cuff layer in the usual manner until it reaches a predetermined course A for beginning the storage compartment layer. To begin knitting the storage compartment layer at course A, every other needle i.e., the "active" needles, is raised up prior to reaching the yarn feed area, by using the jack press and the 1×1 jack selector. The yarn is fed using a yarn finger.
As the needles approach the knitting cam, a divider operating cam arranged on the main drum 22, is actuated to drop needle divider cam from in to out, so as to force the needles not lifted by the jacks, i.e., the "inactive" needles, under the stitch cam block and out of the knitting position. Concurrently, a dial push-out actuator cam also arranged on the main drum is actuated to activate the dial bits. In this way, two dial bits are arranged between each active needle. As the needles take on yarn, so will the dial bits.
In the prior art basic knitting machine, the machine is geared so that two kickers or pawls move forward every four courses, i.e., every four revolutions of the cylinder. When moving forward, the chain pawl kicks the chain wheel which moves the chain. The drum pawl moves backwardly and forwardly as the chain pawl does, but does not actually kick the rack wheel until a change is desired. The drum pawl rides on the rear portion of the pawl lifter as long as plain or flat links are passing under the front portion of the pawl lifter. When a change in the sock is desired, a kick link is placed in the chain. A kick link is similar to a plain link, except that one side of the link is enlarged so that when the kick link passes under the pawl liftor, it raises the front portion of the pawl lifter which, in turn lowers the rear portion of the pawl lifter allowing the drum pawl to kick the drum rack wheel forwardly.
According to a preferred embodiment of the invention, the above-described mechanism is modified by adding an insert arranged onto a rack wheel, which puts the main drum into position so that after one course, the auxiliary kicker actuating cam actuates the auxiliary kicker. The auxiliary kicker prevents the dial bits from coming out all the way. Release of the dial push-out cam then allows the dial bits to come partially in, thus holding the stitches at the desired course. Upon release of the jack selector, jack press and needle divider cam, normal knitting operations resume.
Normal knitting operations proceed until the desired storage compartment layer length is reached. The length of the storage compartment layer must be less than the length of the locking cuff layer.
After knitting the storage compartment layer, the stitches held by the dial bits need to be released. This is accomplished by moving needle divider cam into position. Concurrently, dial push-out actuator cam disposed on the main drum causes the dial bits to extend outwardly. The dial bits come out at a point where the needles will rise on each side of the dial bits. Importantly, each previously inactive needle will now be interposed between two dial bits holding yarn, so that when dial push-in actuator cam causes the bits to retract, the yarn is forced off of the dial bits by these previously inactive needles.
The foregoing is for illustrative purposes only. Modifications can be made in accordance with the invention as defined by the appended claims.
For example, the method and improved knitting machine described above can be modified to be used on a computerized knitting machine. In this case, a computer replaces the drums, and their associated cams, the rack wheel, the auxiliary kicker and the chain, so that the action of needles and dial bits are computer-controlled.
Also, numerous knitting options exist. For example, although the preferred embodiment described above uses a cylinder-type knitting machine having 108 needles, the size of the cylinder may vary depending on the size of the customer. Also, the sock can be solid white, solid color or multi-colored, or the storage area and foot portion can be different colors, or inner layer, outer layer and foot portion all can be different colors. Stripes or other patterns may be added. Also, the sock may be made in any desired length, such as over-the-calf, mid-calf or crew length.
Although the sock described above is a tube sock, it is understood that a definite heel and toe may be created.
Furthermore, although the locking cuff is shown as having an every-other needles selection (1×1) and the storage area is shown as having a three needle up-one needle down selection (3×1), other suitable combination may be used to create any desired ribbing. | A sock includes a foot portion and a knitted-in storage area including an inner locking cuff layer which extends upwardly further than an outer storage compartment layer. Items may be stored between the inner and outer layers, and then the locking cuff is cuffed over the outer layer so as to lock the items within the storage compartment. A method of making and the improved machine therefor are also described. | 3 |
BACKGROUND OF THE INVENTION
The invention relates to a method for producing clutch and/or brake disks for electromagnetic clutches and/or electromagnetic brakes having at least one friction surface element through which the magnetic field flows.
In accordance with the various designs of friction surface elements, for example rotors and armature disks, in electromagnetic clutches or electromagnetic brakes, a series of different methods for producing said friction surface elements has already been proposed. For the purpose of economical production, the design of a friction surface element is often tailored to have the fewest possible parts which make up said friction surface element. For example, friction surface elements which are composed substantially or entirely of soft-magnetic sheet steel are converted into a shape which corresponds to their function by a combination of stamping and extrusion. In order to increase the friction forces, a plurality of slots in the form of an arc of a circle are stamped or cut out of the metal sheet in order to thus delimit a plurality of concentric pole surfaces. Integral friction surface elements can also be produced by all functional geometric structures being formed substantially by casting of the component. Subsequent method steps serve only to achieve the desired accuracy of the final dimensions of the component, with the result that only relatively small quantities of material still have to be removed.
SUMMARY OF THE INVENTION
The object of the present invention is to produce magnetizable friction surface elements, as are used as friction disks in electromagnetic clutches and brakes, in a simple and cost-effective manner while not having an adverse effect on the magnetic guidance properties.
This object is achieved by the invention disclosed herein. In this case, the method can advantageously be adapted to virtually all dimensions and geometries of the friction surface element which are relevant in practice. The method is suitable, in particular, for producing a plurality of variants of this friction surface element or for relatively short production series.
The disclosure also specifies additional dependent claims specify advantageous and expedient developments of the invention.
The invention proceeds from a, for example, flat cylindrical ring disk, one side of said ring disk being intended to be a friction surface and the surface having been smoothed, for example by lathe machining or grinding, for this purpose. In order to be able to magnetically attract the friction surface of a second friction surface element to the first-mentioned surface, at least two concentric pole regions are magnetically delimited from one another. The essence of the invention is that at least one circular slot is cut by lathe machining in the friction surface element from a friction contact surface. In particular, the cut of the circular slot extends only up to a fraction of the material thickness of the disk blank, for example half the disk thickness. The lathe machining affords the advantage that slots which are relatively narrow in comparison to the depth of said slots can be produced. As a result, the remaining friction surface is only slightly reduced by the magnetic delimiting of the pole regions.
Since the workpiece is machined only from one direction during the lathing process, with the material which is removed being transported away in the opposite direction, the thickness of the material which is not cut does not affect the machining. This affords the advantage that there is no upper limit for the height of the starting cylindrical shape.
The guide path of the cutting tool can deviate from a guide direction parallel to the rotation axis during lathe machining. This affords the advantage that a circular slot with a radial cross-sectional profile can be cut, it being possible for this to differ from the shape of a rectangle and to correspond, for example, to a trapezoidal shape.
The circular slots can be cut with a high degree of geometric accuracy on account of the continuously rotating working movement during the lathing operation. In this case, the slots are bounded by walls with a low level of surface roughness. This has proven advantageous for the production of the friction surface elements in as much as the magnetic flow through the pole surfaces is hardly adversely affected by stray flux within the slots despite a low slot width, and the risk of cracks forming is reduced.
An inherent feature of the invention is that the slots are cut in the pole surface along the entire circumference of the circle. Therefore, material bridges are not left between the pole surfaces in the vicinity of the friction contact plane. This prevents non-uniformities in the magnetic field profile and non-uniform friction forces along the edges of the pole surfaces. Accordingly, irregular wear is largely avoided or minimized.
In contrast to machining, for example, with a laser, lathe machining affords the further advantage of a lesser thermal action on the remaining material in the vicinity of the machining zone. Undesired side effects, for example hardening of the edge zone and the accumulation of molten materials in undesirable locations, are therefore advantageously avoided.
In an advantageous embodiment of the invention, the axial thickness of magnetically isolated parts of the friction surface element is determined at least for the most part or predominantly by the lathed slot. The magnetic properties of the disk material can be used to ascertain dimensions for the friction surface element which optimally match the magnetic and mechanical requirements to the component. On account of its accuracy, lathe machining can advantageously be matched to the geometry of a friction surface element which is dimensioned in this way, for the purpose of quick and material-saving machining.
In a further advantageous embodiment of the invention, the magnet isolation of adjacent parts of the friction surface element in the radial direction is generated substantially by the space in the cut slot, which space is singly contiguous in the axial direction from the friction contact surface as far as the webs. The distance, which is created in this way, between the friction contact surface and magnetically conductive connections between the parts of the friction surface element effectively reduces the influence which magnetic bridges can have on the bundling and guidance of the magnetic flux in the vicinity of the pole surfaces. Therefore, the magnetic attraction force is advantageously increased and the frictional connection for the transmission of torque is improved.
It is also preferred for a friction surface element to be partially cut out from the rear face. In this case, cutouts with a relatively large, contiguous material volume are removed, for example with the aid of a coarse milling tool, for the purpose of shortening the machining time. In particular, the material which firstly is not required for the mechanical stability of the friction surface element and secondly, on account of its soft-magnetic property as undesirable magnetic bridges, short circuits the magnetic flux remote from the pole surfaces is removed in the process. Furthermore, this can reduce the weight of the component to a required extent and, moreover, the friction surface element can be matched to spatial conditions at its site of installation.
In a further advantageous application of the invention, a cutout from the rear face penetrates so far that the material of the friction surface element is interrupted as far as the cut slot. The slot therefore forms air gaps in these regions, said air gaps extending continuously in the axial direction from the plane of the pole surfaces or friction contact surfaces as far as the rear face of the friction surface element. This effectively increases the magnetic resistance between the adjacent pole surfaces which are separated by the slot. The degree of efficiency of the electromagnetic clutch or brake can be accordingly improved. Since the component is machined from that side which is opposite the friction contact plane in this method step, different methods and tools can be used for the machining on the side of the friction contact surfaces, irrespective of the accuracy requirements.
The invention can preferably be applied such that a second concentric circular slot is cut in the friction contact surface of a friction surface element by lathe machining, with the result that a magnetically isolated pole surface ring is formed between the radially outermost pole surface and the innermost pole surface. By suitably arranging magnetic resistors in the active opposite friction surface element, the magnetic flux can be forced through said friction surface element, in order to pass through relatively large surface regions of the pole surfaces in a virtually perpendicular manner, with the result that the force-fit connection on the friction contact surface is increased. In this case, the accuracy of lathe machining proves to be advantageous on account of it also being possible to carry out this step with friction surface elements with a relatively small diameter in comparison to other methods.
In a particularly preferred variant of the method according to the invention, so much material is removed on that side of the same friction surface element which is opposite the friction contact surface that a plurality of, in particular still only two, radially running webs connect the pole surface ring to the other friction surface element. This affords the advantage that only the material which either ensures optimal guidance of the magnetic flux or is required for the mechanical stability and reliability of the friction surface element still remains on a friction surface element. Since the pole surface ring, with the exception of the connecting webs, is separated from the adjacent pole surfaces by air gaps and the connecting webs themselves do not reach the plane of the friction contact surface, the method advantageously allows for the pole surface ring to be magnetically isolated within its friction surface element. This assists the multiple change in the magnetic flux in the radial direction between two active friction surface elements and advantageously additionally increases the attraction force between two friction surface elements.
It is further preferred for the circular slots which separate the pole surfaces from one another to be produced with a uniform depth. This has the effect of the magnetic field lines in the plane of the friction contact surface along the circular slots changing only slightly and hardly being influenced by the magnetic short circuit which is formed by the remaining webs. This affords the advantage that an extremely uniform action of force prevails over the entire surface of a pole surface ring, as a result of which the risk of wear on just one side is reduced.
In a particularly advantageous embodiment of the method according to the invention, material is removed, for example by lathe machining, from that side of a friction surface element which is opposite the friction contact surface. As a result, an inner and an outer cylindrical wall can advantageously be formed in the axial direction. In this case, the outer casing surface of the inner wall and the inner casing surface of the outer wall, in particular, are made such that the turns of a solenoid with which the clutch and/or the brake is operated run between said surfaces without making contact with them. Recesses for producing the web elements are then made by milling.
It is also advantageous for the physical geometric structures of a friction surface element, which structures are opposite the friction contact surface, to be pre-formed in a blank with a protruding volume of material by means of casting and/or forging. This allows wear of the tool to be reduced and the machining times to be shortened during removal of material for the final shaping of the component. In particular, shaping the blank by forging is advantageous because the load-bearing ability of the friction surface element can be increased and the risk of cracks forming can be reduced as a result of said forging.
It is also preferred for the material thickness of the pole surface rings to be reduced in one region by lathe machining from the friction contact surface, with the region being positioned so as to at least partially overlap a pole surface slot in a friction contact surface of a friction surface element, which is arranged opposite, as viewed in the axial direction. In this case, it is advantageous when only so much material is removed by lathe machining that a predefined flow-through cross section in the radial direction for the magnetic flux is not exceeded. In this case, the bundling and guidance of the magnetic flux are improved, with the result that the magnetic attraction force in the region of the pole surfaces is increased. It is particularly advantageous when a region of this kind of reduced material thickness extends over a radial extent which exactly overlaps a slot in the second co-acting friction surface element. As a result, the magnetic flux is particularly effectively guided and, at the same time, the surface portion, which is available for frictional contact, in the friction contact surface is optimally utilized.
BRIEF DESCRIPTION OF THE DRAWINGS
The production of the friction surface elements for an electromagnetic clutch is described below with reference to the figures as an example of the implementation of the method according to the invention. The exemplary clutch has a rotor and an armature disk as the friction surface elements. The installation and the design of the drive or output of said clutch are not illustrated here. The pole surfaces at the same time take on the function of the friction contact surfaces in the case of both friction surface elements.
IN THE DRAWING
FIG. 1 a shows a perspective view of a halved armature disk looking at the friction contact surface,
FIG. 1 b shows a perspective view of the halved armature disk from the rear with respect to the friction contact surface,
FIG. 2 a shows a perspective view of a halved rotor looking at the friction contact surface
FIG. 2 b shows a perspective view of the halved rotor from the rear with respect to the friction contact surface.
DETAILED DESCRIPTION
FIGS. 1 a and 1 b illustrate an armature disk 1 which has been produced in accordance with the method according to the invention. The process for production of said armature disk is preferably started from a blank in the form of a cylindrical disk ring, for example by stamping or casting. One side of the disk ring is prepared as a friction contact surface, for example by lathe machining, with the result that the material thickness corresponds to the thickness d.
The armature disk 1 has a friction contact surface 2 a - 2 d . A circular slot 3 a is cut in the direction of the cylinder axis by lathe machining from a plane of the friction contact surface 2 a - 2 d . Two pole surface rings 6 a , 6 b are defined as a result. The slot 3 a is formed at a predetermined depth t of the disk volume, said depth corresponding to approximately half the thickness d of the disk ring in this case. The radial cross section of the slot describes a rectangle, with the shorter side of the rectangle corresponding to the width w of the slots. The regions of the recessed portions 8 a , 8 b can be seen between the pole surfaces 2 a , 2 b and 2 c , 2 d at the pole surface rings 6 a , 6 b , said regions serving for improved guidance of the magnetic flux.
FIG. 1 b shows the rear of the armature disk 1 after the cutouts 4 a , 4 b have been milled out. In this case, the cutouts 4 a , 4 b have been driven forward, for example by milling, to such an extent that the circular slot 3 a is partially interrupted to form a continuous air gap, for example 5 a . As a result, regions which are fitted with pole surfaces form free-standing pole surface rings 6 a and 6 b which continue to be connected to one another only by means of the webs 7 a , 7 b.
FIG. 1 b shows a plurality of connecting webs 7 a , 7 b , the armature disk having a total of three said connecting webs. Said connecting webs connect the outer pole surface ring 6 a to the inner pole surface ring 6 b at the rear of the armature disk 1 . In FIG. 1 b , the illustrated section runs through a web 7 b along the cylindrical axis. The sectional illustration shows, in this case, that cutting the circular slot 3 a in the friction contact surface causes all the webs 7 a , 7 b to move toward the interior of the armature disk by a distance with corresponds exactly to the depth t of the cut in the slot 3 a . The pole surfaces 2 a - 2 d of the armature disk constitute magnetic dipoles because they receive the magnetic flux from a pole surface of a rotor in order to pass on said magnetic flux to an adjacent pole surface of a rotor, which adjacent pole surface is magnetically isolated by a slot. Guidance of the magnetic flux can therefore be improved by the pole surface being slightly recessed in the region which is situated opposite the circular slot between the pole surfaces of a rotor. Recessed portions 8 a , 8 b of this kind are depicted in the pole surface rings 6 a , 6 b . In comparison with the depth t of the circular slot 3 a , the depth v of the recessed region in the pole surface rings 6 a , 6 b is very much smaller since the magnetic flux must not be impeded by this measure.
However, a proportionally increasing cross section in the form of a cylindrical casing is available to the magnetic flux as the radius increases. Therefore, the thickness of the pole surface rings 6 a , 6 b can be accordingly reduced toward the outside by material being removed, for example by milling, from the rear. The pole surface ring 6 a of the armature disk 1 therefore has a lower material thickness than the pole surface ring 6 b.
FIGS. 2 a and 2 b show a rotor 9 which can be produced using the method according to the invention. The friction contact surface 10 of the rotor 9 has a similar structure to that of the armature disk 1 in FIG. 1 a . Two circular slots 11 a and 11 b which are cut in the friction contact surface 10 a - 10 d to a depth s divide the friction contact surface into three pole surface rings 12 a , 12 b and 12 c , with the middle pole surface ring 12 b having a circular recessed portion 13 for guiding the magnetic flux between the two pole surfaces 10 b and 10 c.
The rotor 9 has a total of six webs, four of said webs 14 a , 14 b , 14 c , 14 d being at least partially illustrated in FIG. 2 b . Said webs are partially produced, for example, by milling the cutouts 15 a , 15 b , 15 c . The rotor also has a total of six cutouts, three cutouts 15 a - 15 c from amongst said cutouts being shown in FIG. 2 b . Comparison of FIGS. 1 b and 2 b clearly shows the possibility of matching the shape of the cutouts 4 a , 4 b or 15 a - 15 c and the webs 7 a , 7 b or 14 a - 14 d in the rear of the friction surface elements by milling machining to meet specific mechanical and magnetic requirements.
In the cutouts 15 a - 15 c , the material is removed to such an extent that air gaps 16 a , 16 b which continue from the friction contact surface to the rear are produced outside the region of the webs 14 a - 14 d . The sectional illustration along the rotor axis runs through the two webs 14 a , 14 d and shows that all the webs 14 a - 14 d between the pole surface rings 12 a - 12 c are at a corresponding distance s from the friction contact surface on account of the cut of the circular slots 11 a 11 b.
The view in FIG. 2 b shows the connecting webs 14 a - 14 d of the rotor and the U-shaped ring channel which is surrounded by the inner cylindrical wall 17 and the outer cylindrical wall 18 . The annular channel is provided for holding the coil turns of a solenoid in a contact-free manner. The inner wall 17 and the outer wall 18 bundle the magnetic flux which is generated by the solenoid through which current flows and direct said magnetic flux to the region of the friction contact surface. In order to surround the coil as closely as possible, but without contact, these walls 17 , 18 are preferably produced by lathe machining. The depth of the U-shaped channel and therefore the lathe machining in this region are limited by the dimensions and, in particular, by the required height h of the connecting webs 14 a - 14 d. | A method for producing clutch and/or brake friction disks for electromagnetic clutches and/or electromagnetic brakes having at least one friction surface element through which the magnetic field flows, wherein at least one circular slot is cut by lathe machining in the friction surface element from a friction contact surface, and wherein at least two webs which connect a pole surface ring to the remaining/other friction surface element are made in the friction surface element from that side which is opposite the friction contact surface such that the slots which are cut from the friction contact surface are interrupted remote from the webs to form continuous air gaps. | 8 |
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